Dissertations / Theses: 'Soe longe'

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Souza, Tatiane Furlaneto de. "Drenagem urbana sob cenários de longo prazo visando incentivos ambientais." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-01092008-113635/.

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A presente pesquisa trata do estudo de cenários regionais de drenagem urbana das principais sub-bacias pertencentes à área urbana de São Carlos/SP e da aplicação de incentivos ambientais em escala de lote. As projeções temporais realizadas dizem respeito às mudanças do uso e ocupação do solo para os anos de 2025, 2050, 2075 e 2100. Os cenários de uso e ocupação do solo têm como base os estudos referentes ao Millennium Ecosystem Assessment (Global Orchestration, Order from Strength, Adapting Mosaic e TechnoGarden) e sua adequação na escala local, para macrodrenagem urbana, proposta por Mendiondo (2005). Os eventos pluviométricos utilizados nas simulações dos cenários, por sua vez, foram selecionados em função das condições de umidade antecedente. Para os cenários propostos, foram avaliadas variações dos regimes hidrológico e hidráulico através de curvas de permanência em alguns pontos ao longo da parte de montante da sub-bacia do Monjolinho. Ainda, em escala de lote, é proposta uma metodologia de incentivos ambientais com base no armazenamento potencial de água no lote e na vazão máxima instantânea, para cada cenário estudado. A metodologia proposta de incentivo ambiental revela-se de simples aplicação por parte de órgãos públicos e de rápida obtenção dos resultados. Embora os cenários propostos sejam fictícios, os custos estimados (R$/\'M POT.2\') são aplicáveis para condições atuais.
This research discussed the study of regional scenarios of urban drainage of the main sub-basins belonging to the urban area of San Carlos/SP and the application of environmental incentives in lot scale. The projections of time made are related to changes of use and occupation of land for the years of 2025, 2050, 2075 and 2100. The scenarios of use and occupation of land are based on the studies concerning the Millennium Ecosystem Assessment (Global Orchestration, Order from Strength, Adapting Mosaic and TechnoGarden) and its appropriateness in the local scale, to urban macrodrainage, proposed by Mendiondo (2005). The rainfall events used in the simulations of scenarios were selected for the conditions of background humidity. For the proposed scenarios have been evaluated changes in the hydrological and hydraulic systems through remain curves in some points along the top part of sub-basin of Monjolinho. Still, in scale of lot, is proposed a methodology for environmental incentives based on the potential for water storage in the lot and the maximum instantaneous flow for each scenario studied. The proposed methodology of environmental incentive appears to be the simple application by public agencies and quickly get the results. Although the proposed scenarios are fictitious, the estimated costs (R$/\'M POT.2\') are applicable to current conditions.

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Gendriz, Ignacio Sánchez. "A methodology for analyzing data from long-term passive acoustic monitoring." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-26062017-145831/.

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Despite the extensive Brazilian coast areas, little is known on underwater acoustic environments in Brazil. Acoustic environments (or soundscape) are composed by biological, geological and man-made sound sources. Soundscapes are strongly linked to ecosystems dynamics, and follow temporal patters that can vary at daily and seasonal scales. Thus, for soundscape characterization, it is necessary to undertake sound recordings for long periods, which demands innovative analyzing methods. Accordingly, the present research focuses in two principal objectives: (1) to develop methods for analyzing long-term acoustic recordings and, (2) to characterize marine soundscapes of selected points in São Paulo State. Four deployment sites were selected for the underwater acoustic monitoring: a point located at the channel entrance of the Santos Harbor, and three marine Protected Areas (PAs) in Sao Paulo state. As a result, the largest underwater acoustic database from Brazilian seas was acquired. The present work used Power Spectral Density (PSD), Sound Pressure Level (SPL) and Spectrograms to develop an innovative methodology for analyzing long-term acoustic data. In addition, a new visualization tool and a method for automatic detection of dawn and dusk choruses are presented. The achieved results validated the proposed methodology as an effective tool for analyzing long-term acoustic data. The area close to the first site, the vicinity of Santos Harbor, was dominated by ship noise, which values reach levels that can affect some species of fish and marine mammals. The soundscapes of the other three remaining measurement sites were dominated by fish and crustacean choruses, with daily and seasonal patterns (related to sunrise and sunset). For the monitored regions, the present work signifies the first contribution for cataloguing fish choruses, and establishes a baseline for the study of their underwater acoustic environment. Although the proposed methodology has used long-term undersea acoustic datasets as case-study, it can also be extended for monitoring other aquatic or terrestrial ecosystems. Finally, the research indicates to Brazilian environmental agencies and to the related scientific community that passive acoustic monitoring is a noninvasive and cost-effective tool that can be used for the management of PAs and points of economic relevance.
Apesar da ampla área dos mares brasileiros, pouco se conhece sobre paisagens acústicas submarinas no Brasil. Estas paisagens são compostas por sons de origens biológicas, geológicas e as produzidas pelo homem. As paisagens acústicas estão fortemente ligadas à dinâmica dos ecossistemas, mostrando padrões temporais diários e sazonais. Para caracterizar paisagens acústicas é necessário realizar gravações de sons por períodos de tempos prolongados, o que demanda métodos de análise inovadores. Neste sentido, a presente pesquisa visa dois objetivos principais: (1) desenvolver métodos para a análise de gravações acústicas de longa duração, (2) caracterizar a paisagem acústica do litoral do estado de São Paulo. Quatro pontos de coleta foram selecionados para monitoramento acústico passivo: um ponto situado no canal de entrada do Porto de Santos e os outros três em áreas de proteção marinhas (APM) do estado de São Paulo. Como resultado foi obtida a base de dados de sons submarinhos mais extensa dos mares brasileiros. Do ponto de vista da análise destes dados, o presente trabalho baseia-se no cálculo da Densidade Espectral de Potência, Níveis de Pressão Sonora e Espectrogramas, obtendo métodos de análise novedosos a partir técnicas tradicionais. Neste contexto a tese apresenta uma ferramenta para a visualização de dados acústicos e um método para a detecção automática de coros biológicos matutinos e vespertinos. Os resultados obtidos permitiram validar a efetividade dos métodos propostos na descrição e análise de dados acústicos de longa duração. O ambiente acústico nas proximidades do Porto de Santos foi dominado por ruído de embarcações, alcançando valores de níveis sonoros capazes de afetar algumas espécies de peixes e mamíferos marinhos. As paisagens acústicas dos três pontos restantes foram dominadas por coros de peixes e crustáceos, com padrões diários e sazonais (relacionados ao nascer e pôr do sol). O presente trabalho constitui a primeira pesquisa que cataloga coro de peixes e que estabelece uma referência para o estudo do ambiente acústico das regiões monitoradas. Embora os métodos apresentados usaram como estudo de caso dados de sons submarinos, a sua aplicação pode ser estendida para o monitoramento de outros ambientes aquáticos ou terrestres. Por último, a pesquisa mostra aos órgãos ambientais brasileiros que o monitoramento acústico passivo é uma ferramenta eficaz para o manejo e monitoramento de áreas protegidas e pontos de relevância econômica.

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Gow, Christopher Malcolm. "Iranian cinema in long shot." Thesis, University of Warwick, 2005. http://wrap.warwick.ac.uk/59511/.

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This thesis aims to facilitate a broader understanding of post-revolutionary Iranian filmmaking, by way of an analysis of the New Iranian Cinema and Iranian cinema in exile and diaspora, and the various relationships between these two cinemas. Thus far no significant attempt has been made to consider these two cinemas in relation to each other. This thesis therefore represents a significant contribution to this line of research. Along the way it addresses several key concepts of long-standing importance in film studies, such as notions of art cinema, authorship and national cinema, in particular how such concepts have been used as a means of studying the New Iranian Cinema. Exilic and diasporic Iranian filmmaking represents a challenge to traditional understandings of these concepts. The first chapter therefore examines how the New Iranian Cinema has been received and constructed as an archetypal 'art cinema' in Europe and North America, in addition to how this cinema invites, at the same time as it resists, such interpretations. Thereafter follows a consideration of Iranian emigre filmmaking across Europe and North America, and how it has changed over the past thirty years, gradually shifting from an exclusively exilic to a pan-diasporic outlook. Chapters three and four are individual case studies of Iranian emigre filmmakers Amir Naderi and Sohrab Shahid Saless respectively. As two of Iran's most important and influential pre-revolutionary filmmakers, the works of Naderi and Saless represent not only interesting divergences from the evolutionary understanding of Iranian emigre cinema outlined in the second chapter, but also form two of the most compelling links between the New Iranian Cinema, and it exilic and diasporic counterpart. This thesis concludes by arguing for a more flexible and open-ended conception of national cinema more generally, as well as more comprehensive, nuanced and deterritorialised understanding of post-revolutionary Iranian filmmaking.

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Dirski, Peter. "Expatriation - the SME challenge alternatives to long-term assignments abroad." saarbrücken VDM Verlag Dr. Müller, 2007. http://d-nb.info/991215354/04.

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Carneiro, João Paulo Costa. "Disponibilidade de fósforo em latossolo sob diferentes sistemas de longa duração." Universidade Estadual de Londrina. Centro de Ciências Agrárias. Programa de Pós-Graduação em Agronomia, 2015. http://www.bibliotecadigital.uel.br/document/?code=vtls000203609.

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O fósforo (P) é considerado elemento essencial e insubstituível às plantas. As reservas desse elemento são finitas, a evolução do uso de fertilizantes fosfatados no Brasil é crescente e a tendência é de aumentos consideráveis nos próximos anos. Ademais, o P pode ser fixado nos solos devido à adsorção deste íon a óxidos e hidróxidos de Fe e Al, sendo que este problema torna-se mais grave em solos tropicais muito intemperizados. Por isto, há necessidade do desenvolvimento de trabalhos científicos para aumentar a eficiência de utilização de P nos diferentes sistemas de produção agrícola. Este trabalho teve como objetivo central avaliar os teores de P disponível no solo, ao longo de 24 anos, em diferentes sistemas de manejos e de culturas, em um Latossolo Vermelho Distroférrico (LVd), na região sul do Brasil [clima Cfa (subtropical úmido)]. E os objetivos específicos foram: (i) avaliar a capacidade máxima de adsorção de P (CMAP) e a energia de ligação de um Latossolo Vermelho muito argiloso, sob diferentes sistemas de manejo do solo e de culturas, num período de 24 anos; e (ii) estimar as quantidades exportadas de P nos grãos das culturas de soja, trigo e milho e a eficiência relativa do uso deste elemento nos diferentes sistemas de manejo, em sucessão e rotação de culturas. O delineamento foi de blocos ao acaso, com quatro repetições em esquema fatorial 3x2, sendo constituído por três manejos do solo [sistema de plantio direto (PD), sistema de plantio direto escarificado (PDesc) e plantio convencional (PC)] e dois sistemas de culturas [sucessão (SUC) e rotação (ROT)]. A menor intensidade de revolvimento do solo no PD aumentou os teores de COT e CTC, reduzindo-se, assim, a energia de ligação e aumentando os teores de P disponível para as plantas em relação ao PDesc e PC. No PC não ocorreu aumento significativo dos teores de P disponível ao longo dos 24 anos na primeira camada. Apesar do aumento de P disponível, o plantio direto não aumentou a eficiência de exportação de P pelas plantas em relação aos outros sistemas de manejo. Nesse sentido, a maior influência sobre a extração de P pelas plantas foi ocasionada pelo sistema de manejo de culturas, com maior eficiência de exportação naqueles que utilizaram a rotação. A escarificação periódica do solo não alterou os teores de P disponível ao longo dos 24 anos de manejo e apresentou os menores teores de P disponível em relação ao plantio direto contínuo (PD) e o plantio convencional (PC), não apresentando qualquer vantagem para o balanço da exportação de P em relação ao PD contínuo.
The phosphorus (P) is considered essential and irreplaceable element for plants. The reserves of this element is finite, the evolution of the use of phosphate fertilizers in Brazil is growing and the trend is considerable increases in the coming years. In addition, the P can be fixed in the soil due to adsorption of the ion to oxides and iron and aluminum hydroxides, and this problem becomes more severe in highly weathered tropical soils. Therefore, there is need to develop scientific studies to increase the efficiency of P utilization in different system of agricultural production. This work aimed mainly to evaluate the values of available phosphorus in the soil, over 24 years in different systems of soil management and cultures, in a Rhodic Eutrudox, in southern Brazil [CFa climate]. And the specific objectives were: (i) evaluate the maximum P adsorptioncapacity (MPAC) and the binding energy of an Oxisol clayey under different soil management systems and cultures, within 24 years; and (ii) estimate the amount of P in the exported soybean grains of wheat and maize and the relative efficiency of use of the element in different management systems, succession and crop rotation. The design was a randomized block with four replications in a factorial arrangement 3x2, consisting of three soil managements [no-till (NT), no-till with csideling (NTC) and conventional tillage (CT)] and two systems crops [succession (SUC) and rotation (ROT)]. The stabilization period occurred after 22 years of adoption of the NT and the least amount of soil disturbance in this system increased the TOC and levels of CEC, reducing the binding energy and increasing available P content to plants in relation to NTC and CT. On the PC there was no significant increase in P content available over the 24 years. Despite the increase in available P, the no till did not increase the export efficiency of P by plants, in relation to other management systems. In this sense, the greatest influence on the extraction of P by plants was caused by crop management system, with higher export efficiency in those using the rotation. Periodic soil scarification did not affect the values of available phosphorus over the 24 years of management and had the lowest values of available phosphorus in relatio to no till and conventional tillage, showing no advantage for the balance of exports of P in relation to NT.

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Opolski, Debora Regina. "Análise do design sonoro no longa-metragem Ensaio sobre a cegueira." reponame:Repositório Institucional da UFPR, 2009. http://hdl.handle.net/1884/19870.

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Yarbrough, Christopher Neil. "Pliocene to recent stratigraphy of the Cuu Long and Nam Con Son Basins, offshore Vietnam." Thesis, Texas A&M University, 2006. http://hdl.handle.net/1969.1/3832.

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The Cuu Long and Nam Con Basins, offshore Vietnam, contain sediment dispersal systems, from up-dip fluvial environments to down-dip deep-water slope and basinal environments that operated along the southern continental margin of Vietnam during Pliocene to Recent time. The available data enabled sediment thickness patterns, sequence-stratigraphic relationships, and channel types (fluvial to deep-water channels) within the lower Pliocene to Recent stratigraphic succession in the Cuu Long and Nam Con Son basins of offshore Vietnam to be analyzed. At least nine sequences and their accompanying systems tracts exist in the Pliocene to Recent section. Shelf-edge development in the study area is limited to the Eastern Nam Con Son Sub-Basin. Overall south to southeastward migration of the shelf edge complex during Pliocene to Recent time indicates that the Paleo-Mekong River System was the dominant sediment source for the area.

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Mueller, Jens Helmut Friedrich. "Movements in the Long White Cloud of Governance -Shifts in Attitudes to Governance in New Zealand." Thesis, University of Canterbury. Management, 2014. http://hdl.handle.net/10092/8963.

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This research interrogates a large population of shareholders, senior managers and company directors in New Zealand as to their reasons for considering board service, their competence in governance skills areas, their beliefs as to whether board room diversity is needed and their firms’ interests to recruit further independent directors to their boards. With a considerable deference to the contributions of agency theory as the conventional cornerstone to explain the connection of directors into organizations for the purpose of governance service, this work explores the extension of agency theory by adding an additional driver for governance engagement by company directors: Commitment. Based on this research, company directors in New Zealand appear to base their interest in serving as independent directors on company boards largely on the desire to “do good”. This raises the prospect of a deeper and more meaningful relationship with firms where they serve as directors. Ignorance of this important component of the director/firm relationship by the firms might render directors less willing to contribute and deprive firms of the strong support and engagement of their directors. Lack of recognition of this additional component to the fabric of an enduring committed relationship between external directors and their firms may require a different behavior of firms during the recruitment, board induction training and maintenance of the director relationship. While the strong expression of interest by SMEs in additional independent directors is a welcome sign of rising governance standards in New Zealand’s large group of such enterprises, concern emerges about the potential lack of competence by directors in several areas of governance. While directors appear to compensate for deficiencies in skills with an extra dose of commitment, significant needs for upskilling exists in this sector. It is noted that the absence of well-established, easily accessible and comprehensive director training schemes in New Zealand conflicts with the expected large number of additional independent director recruitments in the near future. Shareholders, senior managers and directors report a need for diversity on boards in the area of business experience, but no specific concern is expressed as to how any specific importance of gender or age while other factors, such as work experience and global knowledge, are of much greater interest. This could indicate that the status quo of only a small number of women on boards in New Zealand is accepted, but in the context of this work more likely indicates that directors will not be recruited (or excluded from recruitment) in the future on the basis of gender. This research attempts to lay groundwork for a more intensive investigation into the true motivations of company directors when they think of an independent director mandate and while they discharge directorship duties. There now appears to be solid evidence that the historic application of agency theory does not completely describe the factors of motivation and relationship under which independent directors serve on company boards.

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PORTO, Nara Raquel Silva. "Estudo comparativo entre instituições de longa permanência para idosos na cidade do Recife sob foco da ergonomia do ambiente construído." reponame:Repositório Institucional da UFPE, 2015. https://repositorio.ufpe.br/handle/123456789/14119.

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No Brasil, a atenção ao envelhecimento deixou de ser apenas uma preocupação das áreas da saúde e socioeconômica, passando a incluir as diferentes ciências, pelas necessidades e exigências do mundo que envelhece, considerando-se o meio em que vivem os idosos, seja o espaço público ou seu domicílio. O surgimento de Instituições de Longa Permanência para Idosos (ILPI´s), os antigos asilos, é uma necessidade cada vez mais presente nesta sociedade envelhecida, que têm a finalidade de proporcionar moradia coletiva em um ambiente seguro, adaptado e com assistência gerontogeriátrica. Inserido nesse panorama, este trabalho integra-se a uma pesquisa mais ampla, que cuida de avaliar e entender as relações humano-ambiente-atividades, quando este humano é uma pessoa idosa e o ambiente é uma residência coletiva destinada a essa população. Nessa perspectiva, e tendo como suporte a ergonomia aplicada ao ambiente construído, este trabalho cuidou em um primeiro momento de investigar uma instituição de longa permanência para Idosos de alto padrão e no segundo momento realizou a comparação do presente estudo com as cinco casas já investigadas pelo grupo de pesquisa, que foram duas públicas, duas particulares e uma filantrópica, podendo assim investigar em que medida o custo de utilização pago pelos usuários residentes influenciam na qualidade das instituições em relação à conforto e adequação às normas e legislações. Tratando-se de um estudo do tipo qualitativo, que utilizou como metodologia de avaliação da Instituição de Longa permanência de alto padrão a Metodologia Ergonômica do Ambiente Construído (MEAC), desenvolvendo uma abordagem ergonômica a fim de entender, avaliar e modificar o ambiente e a interação contínua com seu usuário. Foram identificadas inadequações quanto às normas de conforto ambiental, dimensionamento e acessibilidade na Instituição pesquisada, e quando comparada as outras instituições pesquisadas pelo grupo, percebe-se que o não cumprimento ás normas é uma constante, não estando relacionada a condições financeiras da instituição e sim a falta de informação quanto à importância da ergonomia e o cumprimento da legislação.

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Daneluzzi, Gabriel Silva. "Sinalização elétrica de longa distância pós-irrigação em plantas de girassol sob déficit hídrico." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-06012017-132204/.

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Uma propriedade fundamental dos seres vivos é a condução de sinais elétricos através de seus tecidos. Mas esse fato pouco é lembrado quando se trata de organismos vegetais. Outro item fundamental é a geração de sinais que possam transmitir informações entre os tecidos e órgãos para um ajuste fino do metabolismo. Nas plantas esses sinais podem ser de natureza química, hidráulica e elétrica. Nesse último caso são conhecidos potenciais de ação (PA), de variação (PV), de ferimentos (WP) e sistêmicos (SP), cada um com sua particularidade quanto à amplitude, velocidade e rotas de propagação, bem como seu papel no metabolismo. Os sinais elétricos podem afetar a respiração, fotossíntese, absorção de água, ativação de genes e fechamento de folhas de plantas insetívoras. PAs podem se propagar com velocidade relativamente constante e sem decréscimo. Eles seguem a lei do tudo-ou-nada, ou seja, todo estímulo que desencadeia um PA deve atingir um limiar de excitação para desencadear o sinal. Assim que o limiar é atingido o sinal se autoperpetua ao passo que estímulos supra limiares desencadeiam PAs de amplitude constante. A via de propagação do PA é o vaso do floema. O objetivo do presente trabalho foi avaliar a sinalização elétrica em resposta à irrigação em plantas de girassol sob déficit hídrico e caracterizar esse sinal quanto à amplitude, duração, velocidade e direção de propagação. Para tanto 37 plantas foram avaliadas por meio de eletrodos extracelulares. Elas foram monitoras eletrofisiologicamente durante um período em que eram irrigadas e em um período sob déficit hídrico. Desse montante, onze responderam à irrigação pela geração de potenciais de ação (PA), ou seja, 30% delas. Oito delas geraram PAs em direção ao ápice (propagação acrópeta) enquanto duas geraram na direção basípeta. Uma delas gerou nos dois sentidos. O PA foi gerado também pós-irrigação mesmo com a planta não tendo passado por déficit hídrico, porém só aconteceu em uma das onze plantas. Os sinais se propagaram no caule, pecíolo e nervura central das folhas. O potencial de ação é gerado após irrigação em plantas de girassol com maior frequência quando elas passam por período de déficit hídrico e se propagam por toda a planta. Isso evidencia o papel do PA na sinalização de longa distância nos vegetais.
A fundamental property in the leaving beings is the conduction of electrical signals through their tissues. However, this fact is not always remembered when it comes to plant organisms. Another key process is the generation of signals that can transmit information among tissues and organs to a fine-tuning of the metabolism. In plants, these signals can be chemical, hydraulic and electrical. Concerning the last one, action potentials (AP), variation potentials (VP), wound potentials (WP) and system potentials (SP) are known; each one with its particularity regarding amplitude, velocity and propagation routes as well as its role in metabolism. The electrical signals may affect respiration, photosynthesis, water uptake, activation of genes and leaf closure in insectivorous plants. APs can spread with relatively constant speed and no decrement. They follow the all-or-nothing law, in another words, every stimulus that triggers an AP must reach a threshold to trigger the signal. Once the threshold is reached, the signal is self-perpetuating while stimuli above threshold trigger APs with constant amplitude. The propagation path of the AP is the phloem vessel. The aim of this work was to evaluate the electrical signaling in response to irrigation in sunflower plants under water deficit and characterize the AP regarding its amplitude, duration, velocity and propagation direction. Thirty seven plants were analyzed using extracellular electrodes. They were electrophysiologically monitored during a period when irrigated and in a period under drought. Eleven plants generated AP after irrigation, i.e. 30%. Eight of them generated AP that propagated acropetally while two generated in basipetal direction. One generated in both directions. The action potential was also generated in a plant that was not under drought stress, however it just happened in one of the eleven plants. The signals propagated in the stem, petiole and midrib of the leaves. The action potential is generated after irrigation in sunflower plants more frequently when they go through a period of water deficit and propagate throughout the plant. This highlights the role of AP in long-distance signaling in plants.

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Dixon, Trevor. "Long-term assessments of some vessel-source marine pollutants." Thesis, University of South Wales, 1997. https://pure.southwales.ac.uk/en/studentthesis/longterm-assessments-of-some-vesselsource-marine-pollutants(23bf3738-6f68-47f6-90b0-549f48be5b2a).html.

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Accidental and deliberate discharges from maritime transportation activities have been widely perceived as major sources of pollution. Preventive and control management strategies have therefore been progressively introduced internationally to reduce and eliminate these inputs to the marine environment. The long-term effectiveness of these measures, applied to vessels operating in the waters around the British Isles, is the research question that has been under investigation by the author since 1971. Following analyses of stakeholders' interests and concerns, and associated information requirements, the aims and objectives of a phased work programme were identified. These focused primarily upon three vessel-source marine pollutants; oil or oily mixtures, packaged dangerous or harmful goods and garbage. After a review of the literature, assessment strategies, designs, methodologies and analytical techniques were devised and applied over varying spatial and temporal scales. A data acquisition and management system, utilising questionnaire returns from 13 reporting organisations, was employed to support an annual survey on marine oil pollution. A similar approach, combined with published information, facilitated a characterisation of packaged chemical incidents around the coastline and changes over time. To determine different sources and other attributes of marine litter, an ocean-focused beach survey design was devised and applied on the shores of the English Channel, Irish Sea, North-East Atlantic Ocean and North Sea. A series of surface drift experiments and an open-water sighting survey provided further information on movements and densities of marine litter in the open sea. Research outputs, including the publications submitted, have been reviewed and identified as authoritative sources of information by the competent authorities and other interested parties. These include the Department of the Environment, Transport and the Regions, European Commission, International Maritime Organisation, Royal Commission on Environmental Pollution, Smithsonian Institution for Short-Lived Phenomena and the United States National Oceanic and Atmospheric Administration.

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Tavares, Vera Lúcia. "A busca da excelência no atendimento em uma ILPI sob a perspectiva do sujeito residente." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/12539.

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Aging is a world phenomenon that comprises biological, psychological, and social changes, which many times lead the elder to a total or partial dependence of a caretaker, who are usually the spouses, sons, daughters, daughters-in-law, sonsin- law, nephews, nieces, or grandchildren. Most of these caretakers do not have a healthcare professional background, but are moved by their good will and availability. However, it is noticed that, more and more, these relatives have professional activities out of the house and the Long-Term Stay Institutions (LTSI) many times consist in the only choice for these subjects and their families. The purpose of this study is to identify the will of the residents regarding the LTSI, and what they expect of the place where they live, through a qualitative research. Semi-structured interviews were used as a data collection technique, upon the use of an open-question questionnaire. Reflections regarding the social representations of the residents of this LTSI, which identify their wishes related to the place where they live and what they expect of it, are presented. These reflections also identify the inter-relations among residents and how they relate to the institution managers, contributing for the resident to preserve his/her functional ability and autonomy. There are also suggestions for the elaboration of action plans for the continuous healthcare improvements to these residents, turning the LTSI into a pleasant community, which provides them with quality of life and preserves their identities
O envelhecimento é um fenômeno mundial que pressupõe alterações biológicas, psicológicas e sociais, que muitas vezes leva o idoso a uma dependência total ou parcial de um cuidador que geralmente são os cônjuges, filhos, noras, genros, sobrinhos ou netos. Esses cuidadores em sua maioria não dispõem de uma formação profissional de saúde, mas são movidos por sua boa vontade e pela disponibilidade. Porém, percebe-se que cada vez mais, esses familiares exercem atividades profissionais fora do lar e as Instituições de Longa Permanência para Idosos (ILPIs) constituem-se muitas vezes, na única opção para esses indivíduos e suas famílias. O objetivo deste estudo é identificar os desejos dos moradores com relação a ILPI, e o que eles esperam do lugar onde moram, através de uma pesquisa qualitativa. Foi utilizada como técnica de coleta de dados, entrevistas semi estruturadas, mediante a utilização de um questionário com questões abertas. Apresento reflexões que se referem às representações sociais dos moradores que vivem nesta ILPI, identificando seus desejos com relação ao local onde residem e o que esperam deste local. Identificando ainda as relações dos moradores entre si e como se relacionam com os dirigentes da instituição, contribuindo para que o idoso morador preserve sua capacidade funcional e autonomia e também através de sugestões para a elaboração de planos de ação para melhorias contínuas de assistência a esses moradores, tornando a ILPI uma comunidade aprazível, proporcionado-lhes qualidade de vida e preservando sua identidade

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Auby, Antoine. "Modélisation à haute résolution du transport de polluants à longue distance." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00735198.

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La pollution de l'air peut être transportée sur des distances de plusieurs milliers de kilomètres par la dynamique de grande échelle. Elle affecte ainsi le climat et la qualité de l'air loin des régions sources. Durant leur transport, les panaches de pollution voient leur composition altérée par le mélange avec l'air environnant. Les modèles globaux eulériens utilisés pour calculer les bilans d'export de polluants ne représentent pas bien le transport des panaches du fait de leur faible résolution, ce qui induit des erreurs dans le calcul de ces bilans et dans les vitesses de réaction du fait de la non-linéarité de la photochimie atmosphérique. Cette thèse a pour but de contribuer à améliorer la compréhension et la quantification du mélange subi par les panaches de pollution dans la troposphère libre lors du transport à longue distance, et sa représentation dans les modèles numériques. Elle se focalise sur l'Arctique, une région vulnérable au changement climatique, où la distribution des gaz à effet de serre et des aérosols est fortement influencée par le transport de polluants depuis les moyennes latitudes. Les travaux effectués s'organisent autour de trois études de cas de transport dans la troposphère arctique, dans le cadre de la campagne aéroportée POLARCAT durant l'été 2008. Les résultats obtenus permettent d'estimer que l'intensité du mélange dans cette région est plus faible qu'aux moyennes latitudes. Ils montrent également qu'une approche lagrangienne permet de reproduire la variabilité des concentrations dans les panaches âgés, de simuler le transport des structures de petite échelle, et d'évaluer la variabilité de l'évolution des concentrations en ozone dans les panaches induite par les différents scénarios de mélange. Les résultats de ces modèles lagrangiens permettent aussi de jauger les performances des modèles globaux eulériens en terme de transport des polluants en Arctique, et de définir la résolution spatiale nécessaire pour représenter ce transport de façon satisfaisante. Les trois études présentées concordent sur l'importance de combiner les approches lagrangienne et eulérienne pour simuler le transport à longue distance dans les modèles numériques.

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Leidwanger, Cathy. "Etude des tassements différés à partir de résultats d'essais au diflupress longue durée." Grenoble 1, 1993. http://www.theses.fr/1993GRE10153.

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L'observation des tassements differes de batiments lourds a montre la difficulte d'obtenir une bonne prevision des tassements a long terme a partir des seuls essais de laboratoire. E. D. F. A alors developpe un appareil de mesure in situ du comportement differe des sols sous chargement constant, le diflupress l. D. L'analyse des essais au diflupress conduit a la definition d'une pente de fluage. Cette derniere peut etre liee a la contrainte appliquee au sol par la sonde par des relations analogues a celles utilisees pour l'exploitation des essais de fluage en laboratoire. En adaptant les formulations classiques de calcul previsionnel de tassement, on obtient les tassements differes a partir de la caracteristique mesuree au diflupress. L'etude fine de l'ensemble des batiments de deux sites nucleaires fournit une relation entre la deformation differee de la couche compressible et la contrainte induite dans le sol sous chaque batiment. Cette deformation peut etre liee a la caracteristique mesuree au diflupress: on obtient alors une methode simple de prevision du tassement. On utilise egalement les resultats des essais au diflupress l. D. Afin d'identifier les parametres elastoviscoplastiques du modele de comportement de dafalias-kaliakin. On utilise cette loi dans le code aux elements finis lagamine, seule ou couplee avec une loi d'ecoulement qui permet de tenir compte de la presence d'eau interstitielle. On modelise ensuite le tassement differe des centrales nucleaires avec les parametres identifies a partir de l'essai au diflupress: on obtient une pente de tassement differe proche de celle observee sur le site. Une etude fine des chemins de contraintes suivis sous l'ensemble de la fondation, conduit a une approximation possible pour le chemin suivi. On constate egalement que la partie visqueuse du modele est active essentiellement sous la fondation. Cela aboutit a l'elaboration d'une methode simplifiee a partir de la reduction unidimensionnelle de la loi de dafalias-kaliakin

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Dennis, Johansson. "Search Engine Optimization and the Long Tail of Web Search." Thesis, Uppsala universitet, Institutionen för lingvistik och filologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-296388.

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In the subject of search engine optimization, many methods exist and many aspects are important to keep in mind. This thesis studies the relation between keywords and website ranking in Google Search, and how one can create the biggest positive impact. Keywords with smaller search volume are called "long tail" keywords, and they bear the potential to expand visibility of the website to a larger crowd by increasing the rank of the website for the large fraction of keywords that might not be as common on their own, but together make up for a large amount of the total web searches. This thesis will analyze where on the web page these keywords should be placed, and a case study will be performed in which the goal is to increase the rank of a website with knowledge from previous tests in mind.

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Fernandez, Mathieu. "Approche topographique historique du sous-sol parisien 1800-2000 : la ville épaisse : genèse et évolutions morphologiques." Thesis, Paris, CNAM, 2014. http://www.theses.fr/2015CNAM0982/document.

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Le sous-sol de Paris est reconnu et topographié depuis environ deux siècles par plusieurs disciplines. Dans cette thèse, nous avons retenu et analysé depuis leur genèses, souvent intimement liées sur le territoire urbain, ces disciplines de l’épaisseur : la géologie, l’hydrogéologie, l’archéologie, la topographie, puis ce que nous nommons actuellement le génie urbain. L’urbanisme, accepté comme « science de l’organisation spatiale des villes », possède peu de méthodes d’appréhension à même de synthétiser dans le temps et l'espace la diversité de ces approches. La méthode proposée par la thèse rend représentables et quantifiables plusieurs évolutions longues issues des « mesures de ville » étalées dans le temps, à travers un Système d’Information Géographique construit dans une perspective diachronique. Il concerne ici spécifiquement la verticalité. Plusieurs cartographies originales concernant le mouvement du sol et de la nappe phréatique en sont issues.Sur la base de ce support, intégrant la topographie historique, environnementale et tridimensionnelle de plusieurs disciplines urbaines, nous développons deux pistes d’analyse.La première est la compréhension de la construction du projet urbain au XIXe siècle jusqu’aux « grands travaux » à la lumière de la mesure de l’espace et des représentations disponibles. Une chronologie spécifique est proposée.La seconde est une proposition pour un récolement urbaniste souterrain appréhendant le temps long et l'épaisseur de la ville. Elle peut contribuer aux bases de données urbaines, actuellement en majorité construites sur un espace conçu comme parcellaire.Le modèle vise donc à fournir une contribution et de nouvelles pistes de recherches à la fois pour la morphologie préindustrielle de Paris, pour l’archéologie industrielle et plus généralement pour l'approche urbaniste de la couche, désormais connue dans un cadre géologique et environnemental, mais encore non définie du point de vue stratigraphique, sous le nom d'anthropocène
For more than two centuries now, researchers from different backgrounds and disciplines have started studying and making topographical surveys of the Parisian underground.These different ways of studying urban thickness all inform this thesis. They are all analyzed from their very origins, which are often closely linked in an urban context. These methods include: geology, hydrology, archeology, topography, and what is currently called urban engineering. Urbanism, although it is often described as “the science of spatial organization in cities”, can seldom yield as much temporal and spatial information as these various approaches can when put together. This thesis proposes to present and quantify several long-term evolutions, traced through a series of “urban measurements” performed over time by a Geographical Information System, which was designed for the purposes of a diachronic study. The system here specifically targets urban verticality. It has resulted in the creation of many original maps of ground and ground-water movement.Based on these maps, which include historical, environmental and tridimensional topography, two analyses are then conducted.The first deals with understanding the construction of an urban project in the 19th century - up until the “grands travaux” - by looking at space measurement and available representations. A specific chronology is then proposed.The second analysis offers to compile information concerning the thickness of the urban underground and its evolution through time. This could then dispense information to urban databases, many of which are currently based on an urban space fragmented by plots.The model thus built serves to contribute and to give new research perspectives, to the study of Parisian preindustrial morphology, and industrial archeology, and more generally the urban approach of the layer - known in geological and environmental contexts, but which has yet to be defined from a statigraphic point of view - under the name anthropocene

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Silva, Vagner Lopes da. "Qualidade estrutural de um Latossolo sob sistemas de culturas em plantio direto de longo prazo." reponame:Repositório Institucional da UFPR, 2012. http://hdl.handle.net/1884/26070.

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Resumo: Plantio direto de qualidade depende, entre vários fatores, de um manejo adequado do solo que promova sua qualidade estrutural; e isso resulta, também entre vários fatores, de um adequado sistema de culturas baseado em rotação. O objetivo deste trabalho foi avaliar a contribuição de sistemas de culturas de longo-prazo (18 anos) na qualidade estrutural de um Latossolo Vermelho sob plantio direto nos Campos Gerais do Paraná. Foram avaliados cinco sistemas de culturas: trigo-soja [Tr-So]; aveia-milho-trigo-soja [Av-Mi-Tr-So]; ervilhaca-milho-trigo-soja [Er-Mi-Tr-So]; azevém-milho-azevém-soja [Az-Mi-Az-So]; e alfafa-milho [Alf-Mi]. Amostras de solo foram coletadas nas camadas de 0-5, 5-10 e 10-20 cm, em anéis volumétricos (5,6- cm de diâmetro e 3,1-cm de altura) e em torrões (10 cm × 10 cm × espessura da camada). Na camada de 0-5 cm, as menores densidades de solo ocorreram nos sistemas Av-Mi-Tr-So (0,96 Mg m-3) e Er-Mi-Tr-So (0,93 Mg m-3). Nas camadas de 5- 10 e 10-20 cm, as menores densidades ocorreram no sistema Alf-Mi (1,14 e 1,17 Mg m-3, respectivamente). Tendência coerente foi observada para a macroporosidade, que na camada superficial foi maior nos sistemas Av-Mi-Tr-So (0,29 m3 m-3) e Er-Mi- Tr-So (0,30 m3 m-3) e nas camadas de 5-10 e 10-20 cm tendeu a ser maior no sistema Alf-Mi (0,19 m3 m-3). A microporosidade não apresentou tendência clara entre os sistemas. A condutividade hidráulica saturada teve relação direta com a macroporosidade, com Er-Mi-Tr-So apresentando o maior valor na camada de 0-5 cm (224 mm h-1) e Alf-Mi nas camadas de 5-10 (170 mm h-1) e 10-20 cm (147 mm h- 1). O sistema Er-Mi-Tr-So apresentou o menor diâmetro médio ponderado úmido de agregados na camada de 0-5 cm (2,39 mm) enquanto Tr-So o maior (3,04 mm). Os maiores valores de resistência à penetração foram observados no sistema Tr-So, superando 1,5 MPa na camada de 7,5 a 22,5 cm de profundidade. O sistema Alf-Mi apresentou o menor grau de compactação (0,2 MPa cm). Os resultados para os atributos físicos são atribuídos principalmente à ação das raízes das espécies que constituem os sistemas de culturas, e a intensidade de tráfego de máquinas em cada sistema. Considerando-se a camada de 0-20 cm como um todo, o sistema semiperene Alf-Mi possui maior capacidade em promover melhorias na qualidade estrutural do solo em relação aos sistemas baseados em cultivos de espécies anuais. Sistemas bi-anuais de rotação, baseados em plantas de cobertura como aveia preta ou ervilhaca possuem maior capacidade em promover melhorias na qualidade estrutural do solo em relação à sucessão trigo – soja.

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Gomes, Murilo Veloso. "Mecanismos de estabilização de carbono em argissolo subtropical sob sistemas de manejo de longa duração." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/178424.

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No Brasil, o acúmulo de carbono orgânico no solo (COS) tem sido obtido em plantio direto (NT), que faz parte do plano de agricultura de baixo carbono para a mitigação da emissão de gases do efeito estufa. Quando combinado com leguminosas de cobertura, o NT pode resultar ainda em maiores taxas de acúmulo de COS. Baseado num experimento de 30 anos, seis estudos foram realizados com o objetivo geral de avaliar o efeito de dois métodos de preparo (preparo convencional –CT e NT) com três sistemas de culturas [aveia/milho (O/M), ervilhaca/milho (V/M) e o consórcio aveia+ervilhaca/milho+caupi (OV/MC)] sobre os mecanismos de estabilização do C e consequente potencial de sequestro de COS em camadas superficias e subsuperficias de um Argissolo subtropical do Sul do Brasil. O primeiro estudo engloba uma metaanálise global avaliando o potencial do NT em acumular COS. Os resultados deste estudo mostraram um grande potencial de acumular COS em regiões tropicais e subtropicais, o que foi explicado pela alta precipitação média anual nessas regiões. O segundo e terceiro estudos mostraram um importante mas diferenciado papel do plantio direto e das leguminosas de coberturas sobre a estabilização do C no solo, sendo que o não revolvimento favoreceu a oclusão da matéria orgânica em macroagregados enquanto que as leguminosas favoreceram a associação organomineral em microagregados Neste estudo, a importância dos macroagregados sobre a associação organomineral foi enaltecida. Além disso, o quarto estudo revelou forte contribuição das leguminosas de cobertura sobre o potencial de acumular COS em NT, sendo que altas taxas de acúmulo de COS ocorreram durante um período mais longo em camadas subsuperficias do solo. No quinto estudo, uma combinação de fracionamento densimétrico e granulométrico com análises de carboidratos e n-alcanos foi realizada objetivando maior entendimento do papel das leguminosas de cobertura sobre o acúmulo de C em associações organomineral. Este estudo deu suporte à hipótese que o acúmulo de C adicional na fração argila em camadas superficiais e subsuperficias do NT com leguminosas de cobertura é microbiologicamente processado. No sexto estudo, encontramos que o maior teor de C na fração leve do solo sob plantio direto e leguminosas de cobertura favoreceu a comunidade de fungos que, por sua vez, mediou a melhora na agregação de solo. O acúmulo de constituintes da parede celular de fungos contribuiu, portanto, ao acúmulo de COS e agregação de solo sob plantio direto e leguminosas de cobertura.
In Brazil, soil organic carbon (SOC) accumulation have been observed under notillage (NT) which is part of a low carbon agriculture plan for mitigation of greenhouse gases emissions. When combined with legume cover crops, NT could result in even greater soil organic carbon (SOC) sequestration rate than NT alone. Using a 30-year experiment, we performed six studies for which the general objective was to evaluate the effect of two tillage (conventional system – CT and NT) with three cropping systems [oat/maize (O/M), vetch/maize (V/M) and the consortium oat+vetch/maize+cowpea (OV/MC)] on stabilization mechanisms of C and consequent SOC sequestration potential in both the superficial and sub-superficial soil layers of a subtropical Acrisol of Southern Brazil. Encompassing a meta-analysis evaluating the potential of NT in accumulate SOC around the world, the first study showed a great potential in tropical and subtropical regions to accumulate SOC that was explained by the high mean annual precipitation. In addition, the second and third studies showed the meaningful but differential roles of no-tillage and legume cover crops on C stabilization with the former favoring occlusion in soil macroaggregates and the latter, mineral-organic association in soil microaggregates. In these studies, we supported the importance of macroaggregates to the mineral-organic association The fourth study revealed the strong contribution of legume on the potential of SOC sequestration in NT, and high rates of C accumulation occurred over a longer period in sub-superficial soil layers. In the fifth study, we used density and particle size fractionation in combination with carbohydrate and nalkane analyses to provide better understanding of the effect of legume cover crop on C accumulation in mineral-organic association. This study gives support to the hypothesis that the additional clay-bound SOC accumulation at depth under NT with legume cover crops is microbially processed. In the sixth study, we found that the greater C content in light fraction under NT and legume cover crops favoured the fungal community which, in turn, mediated the improvement in soil aggregation. The accrual of fungal cell-wall constituents contributed therefore to SOC accumulation and soil aggregation under NT and legume cover crops.

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Riello, Giorgio. "The boot and shoe trades in London and Paris in the long eighteenth century." Thesis, University College London (University of London), 2002. http://discovery.ucl.ac.uk/1317575/.

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This thesis examines the evolution of pre-industrial shoemaking in London and Paris between the 1680s and the 1850s, treating this period as a whole. The relevance of these two cities is based on the international role they played in the clothing sector. Both cities not only dominated national manufacturing, but were able to influence the standard of production and European fashion. My research aims to construct a comparison of the two productive centres leading to a contrasting study of pre-conditions, strategies and influences in shoemaking. The starting point is a broad view of the 'regulative framework' of the sector: the importance of the raw material market (leather and textiles) and the role of guilds, their organisation and their control of the market. A chapter dedicated to consumption explores the relationship between the London shoe market and the influence of Parisian fashion. The interest in consumption is motivated also by the debate on what economic and social historians consider to be 'mass production' as the other face of 'mass consumption'. A chapter dedicated to retailing tries to link consumption to production. My research is then focused on a study of the organisation of production in the two cities. Different typologies of producers are related to different consumer choices showing how new consumer practices and retailing facilities re-shaped production. Finally the link between fashion changes and marketing techniques (for instance the use of sizes, brands or the distinction between right and left shoes) is a fruitful field of comparative research. The last two chapters of the thesis focus on the first half of the nineteenth century. Particular attention is dedicated to the importation into England of large quantities of women's shoes from France. The crisis that the London sector faced after 1815 explains a series of changes in the market and in the role played by the British metropolis in directing the sector. Very different appears to be the Parisian case, where provincial producers flourished only after the mechanisation of the sector. By the 1850s mechanisation meant the beginning of a new phase in the trade.

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Gutnik, Fabrice. "La présentation de soi de cadres au chômage de longue durée en situation de groupe de fromation d'aide à la réinsertion professionnelle : des lieux et des hommes." Paris, CNAM, 2005. http://www.theses.fr/2005CNAM0518.

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La présentation de soi des cadres au chômage de longue durée en situation de groupe de formation d'aide à la réinsertion professionnelle, en tant que phénomène social total, constitue l'objet de recherche de cette thèse. A partir de la mise en oeuvre d'un dispositif méthodologique d'analyses psychosociales et pragmatiques des interactions verbales des participants à une session de formation, l'hypothèse selon laquelle ce qui fait autorité dans l'image de soi participe de raisons d'agir dont les normes communes et/ou partagées déterminent, a priori, le sesns des lignes d'action possibles à adopter en contexte, est vérifiée. Les résultats de cette recherche distinguent, d'une part, l' intelligibilité des actes sociaux produits et leurs constructions discursives, c'est-à-dire l'agir expressif, et, d'autre part, l'intelligibilité des actes sociaux produits et leurs constructions diversives, c'est-à-dire l'agir expressif, et d'autre part, l'intelligibilité des règles constitutives de trois formes exclusives de présentation de soi faisant montre de trois èthé, soit l'agir normatif
The self-presentation of long term unemplyed managers who attend training groups with the object of rejoining professional life as a total social phenomenon, is the research object of this thesis. From the implementation of a methodological plan whiwch analyses in a psychological and pragmatic way the verbal interactions of the people taking part in a training session, the hypothesis according to which what is accepted as an authority in the self-image is part of reasons to act which common and/or shared norms determine, a priori, the meaning of the possible lines of action to adop in context, is confirmed. The results of this research distinguish, on the one hand the intelligibility of produced social actions and their discursive structures that is expreeive acting, and on the other hand, the intelligibility of the component rules of the three exclusive forms for self-presentation showing the three ethe that is normative acting

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Queyrel, Wilfried. "Modélisation du devenir des pesticides dans les sols à partir d'un modèle agronomique : évaluation sur le long terme." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066566/document.

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Le module de transfert de pesticide PeStics a été intégré au sein du modèle agronomique STICS (Simulateur mulTIdisciplinaire pour les Cultures Standard) afin de simuler le transfert de pesticides dans les sols agricoles. Par la suite une évaluation sur trois sites expérimentaux a été effectuée. Afin d'étudier le devenir des pesticides à l'échelle du bassin versant de l'Orgeval, des simulations concernant 4 herbicides (l'atrazine, la simazine, l'isoproturon, le chlortoluron) et un métabolite (la DEA) ont été réalisées à l'aide du modèle STICS sur une période de 23 ans (1990-2012) . Les objectifs de ces travaux étaient :i) de mettre en évidence les principaux processus impliqués dans la dissipation et le transfert de pesticides à long terme ; ii) d'évaluer l'influence de la dynamique des stocks en pesticide dans les sols, sur le transport en phase dissoute, vers le reste de l'hydrosystème ; iii) de déterminer les paramètres du modèle les plus sensibles aux pertes par lixiviation sur la période de 1990-2012. Les simulations ont été comparées aux observations disponibles sur le bassin versant. Les résultats mettent en avant la nécessité de prendre en considération la dynamique des stocks restants dans les sols pour comprendre le transfert des pesticides sur le long-terme. Une attention particulière doit également être portée sur les paramètres qui influencent la rétention et la disponibilité des pesticides à la lixiviation. En conclusion, les différences obtenues entre les flux lixiviés simulés pour une culture de blé et de maïs montrent l'intérêt des modèles agronomiques dans la modélisation du devenir des pesticides à l'échelle du bassin versant
A pesticide fate module was implemented in the crop model STICS (SimulateurmulTIdisciplinaire pour les Cultures Standard) in order to simulate pesticidetransfer in agricultural soils. Then the model has been evaluated with three studysites datasets. In order to study the fate of pesticides at the scale of the Orgeval catchment, simulations of four herbicides (atrazine, simazine,isoproturon chlortoluron) and one metabolite (DEA) were carriedout with the crop model STICS over a 23-year period (1990-2012). The objectives of the study were i) to highlight the main processes implied in pesticide fate and transfer at long-term; ii) to assess the influence of the dynamics of the remaining mass of pesticide in soil on transfer; iii) to determine the most sensitive parameters related to pesticide losses by leaching over a 23-year period.Simulations were compared against available observations at the catchment scale. The findings of the study show that the dynamic of the remaining mass ofpesticide in soil is a relevant issue to understand pesticide dissipation at longterm. Attention must be paid on parameters influencing sorption and availabilityof the pesticide for leaching. To conclude, the significant discrepancies in the simulated pesticide leaching for the two types of crops (maize and wheat) highlight the interest of using a crop model to simulate the fate of pesticides at the catchment scale

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Casali, Carlos Alberto. "Sistemas de culturas sob diferentes manejos por longa duração alteram as formas de fósforo do solo?" Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/3340.

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The thesis objective was to evaluate the forms of accumulation and release of phosphorus from cover crops waste under long time of different soil management systems and its relationship with the soil phosphorus forms. The experiment was established in 1986 on an Oxisol in the IAPAR experimental station in Pato Branco, Paraná State, Brazil. The treatments consisted of six winter cover crops (blue lupine, vetch, oats, radish, rye and wheat) and the winter fallow treatment, cultivated under no-tillage (NT) and conventional (CT). In September 2011 were collected soil samples (0-5 and 5-10 cm) and the shoots of winter cover crops. Confected litterbags (0.2 x 0.2 m) were collected at 7, 14, 28, 56 and 112 days after the cover crops management. In the residues collected, we assessed the accumulation of C, N, P, and held the fractionation of P. In the soil samples, we made the separation of aggregates by wet way and in the original soil and aggregates we evaluated the content of total C, N, P, the P forms, and the acid phosphatase activity. The distribution of P forms in the cover crops tissue varies among species and their accumulation was a function of nutrient soil P availability, as in NT. But for all of them, the soluble inorganic P was the principal storage form. The release of P from plant residues depends not only on its rate of decomposition, but also on the content of total and soluble P. The vetch and rye have great potential to recycle soil P, and this amount of P should be considered when prescribing phosphorus fertilization for the culture implanted in sequence. However, the long term cultivation of different winter cover crops did not affected the soil P forms in highly weathered clay soils, managed under NT and CT. On the other hand, practices that favor the accumulation of organic residues on the soil surface as the NT system, increase the acid phosphatase enzyme activity and labile organic and inorganic P forms, besides the formation of larger aggregates, which have higher levels of C, N, total P and organic labile P.
O objetivo desta tese foi avaliar as formas de acúmulo e liberação de fósforo dos resíduos de plantas de cobertura sob diferentes sistemas de manejo de solo por longa duração e sua relação com as formas de fósforo no solo. O experimento foi instalado em 1986 sobre um Latossolo Vermelho distroférrico da estação experimental do IAPAR em Pato Branco, estado do Paraná. Os tratamentos consistem em seis plantas de cobertura de inverno (tremoço azul, ervilhaca comum, aveia preta, nabo forrageiro, centeio e trigo) mais uma parcela que permanece em pousio no período de inverno, manejadas sob sistema plantio direto (SPD) e sistema de cultivo convencional (SCC). Em setembro de 2011, coletaram-se amostras de solo (0-5 e 5-10 cm) e da parte aérea das plantas de cobertura de inverno. Confeccionaram-se bolsas de decomposição (0,2 x 0,2m), que foram coletadas aos 7, 14, 28, 56 e 112 dias após o manejo das plantas de cobertura. Nos resíduos coletados, avaliou-se o acúmulo de C, N, P e o realizou-se o fracionamento do P. Nas amostras de solo, realizou-se a separação de agregados por via úmida e, no solo original e nos agregados, realizou-se a avaliação dos teores de C, N, P e o fracionamento de P, e da atividade de fosfatase ácida. A distribuição das formas de P no tecido das plantas de cobertura varia entre as espécies e a sua acumulação foi função da disponibilidade de P no solo. Mas, para todas elas, o P inorgânico solúvel foi a principal forma de armazenamento. A liberação de P dos resíduos das plantas de cobertura não depende apenas da sua taxa de decomposição, mas também do teor total e solúvel de P. A ervilhaca comum e o centeio possuem grande potencial para reciclar P do solo, sendo que essa quantidade de P deve ser considerada na prescrição da adubação fosfatada da cultura implantada em sequência. Contudo, o cultivo de plantas de cobertura de inverno por longo período não alterou as formas de P em solo argiloso altamente intemperizado, manejado sob SPD e sob SCC. Por outro lado, práticas que propiciem o acúmulo de resíduos orgânicos na superfície do solo, como o SPD, elevam a atividade de fosfatase ácida e as formas lábeis orgânicas e inorgânicas de P, além da formação de agregados maiores, os quais apresentam teores mais elevados de C, N, P total e P orgânico lábil.

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Figuerêdo, Karolline Sena. "Alterações de longo prazo dos estoques e qualidade da matéria orgânica em latossolo sob olericultura intensiva." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/10433.

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Fundação de Amparo à Pesquisa do Estado de Minas Gerais
As mudanças nas reservas de C e N refletem os impactos do uso e manejo do solo. Objetivou-se avaliar as mudanças nos estoques e na qualidade da matéria orgânica em Latossolo Vermelho-Amarelo cultivado com olerícolas na região dos Cerrados no Sudeste brasileiro. Quatro áreas foram selecionadas, sendo uma sob vegetação de Cerrado (CE) e três sob produção olerícola com 15 (HT15), 20 (HT20) e 30 (HT30) anos de cultivo. Amostras de solo foram coletadas nas profundidades 0-30, 30-40 e 70-100 cm, realizando-se análises físicas (densidade e textura), químicas (complexo sortivo, pH, C extraído com água, C e N totais, C lábil, C e N nas frações MOP e MAM, lignina, carboidratos, lipídeos e ataque sulfúrico), biológicas (C e N microbianos) e mineralógica (difratometria de raio-X). Os estoques de C e N totais, os teores de C não lábil, o índice de manejo de carbono (IMC), o quociente microbiano (qMic) e as relações C:N total, microbiana e da MOP e MAM foram calculados. Adotou-se o delineamento inteiramente casualizado e o esquema de parcelas subdivididas, sendo os resultados avaliados, individualmente, por comparações de médias pelo teste Tukey e, em conjunto, por componentes principais. Houveram semelhanças entre usos quanto aos estoques de NT e, na área cultivada por 30 anos (HT30) foram observados os menores estoques de CT, tendo o Cerrado (CE) os maiores resultados. Constatou-se que, com o maior tempo de cultivo, houve diminuição nos teores de C lábil. Na composição bioquímica da MOS, ocorreu aumento e redução nas proporções de carboidratos e lignina na MOP e MAM, respectivamente, nos usos HT15 e HT20. A MOP apresentou-se mais sensível às mudanças de uso. Na análise de agrupamento, os resultados mostraram maior similaridade entre HT15 e HT20, assim como a distinção entre CE e HT30. Há uma maior relação de reservas lábeis (CL, carboidratos) com as áreas de menor tempo de atividade e de Cmic com o uso de 30 anos. Pode-se observar, também, a correlação negativa entre nutrientes no solo e os teores de C e N totais e da MAM e de carboidratos da MAM, como também entre Cmic e CT. A olericultura em Latossolo oxídico promove a redução dos estoques de matéria orgânica do solo e altera sua qualidade. Contudo, com 15 e 20 anos pode-se observar incrementos suficientes de C para a manutenção da MOS e obtenção de IMCs maiores que CE e HT30.
Changes in C and N pools reflect the soil use and managements impacts.It was aimed to evaluate changes in soil organic matter storage and quality in Oxisol with olericulture in the Cerrado region in southeast Brazil. Four areas were selected, being one under Cerrado vegetation (CE) and three under olericulture production with 15 (HT15), 20 (HT20) and 30 (HT30) years of cultivation. Soil samples were collected at depths 0-30, 30-40 and 70-100 cm, making physical analyzes (bulk density and texture), chemical (exchangeable cations, pH, C extractable with water, total C and N, labile C, C and N in POM and MOM fractions, lignin, carbohydrates, lipids an sulfate attack), biological (microbial C and N) and mineralogical (X-ray diffraction). It was calculated total Cand N, non-labile C content, IMC, qMic and total, microbial, POM and MAM C:N ratios. It was adopted a completely randomized design and the split plot, the results was evaluated individually by comparisons of means by Tukey test and, together, by principal componentes. There was similatity of TN stocks between uses and 30 years cultivated land had the lowest TC storage, with CE containing the hieghest ones. The longer cultivation promoted a decrease in labile C content. Biochemical composition of SOM had an increase and decrease in carbohydrates and lignin proportions in POM and MAM, respectively, in HT15 and HT20 uses and MOP was more sensitive to land use change. In grouping analysis, data showed greater similarity between HT15 and HT20 and a distinction between CE and HT30. There was a higher relation of labile pools (LC and carbohydrates) with lands with less time of activity production and Cmic with 30 years cultivation. In addition, it can be observed the negative correlation between soil nutrients with total, POM and MAM’s C and N contents and carbohydrates in MAM, as C mic and TC. Horticulture in Oxisol promotes reduction on soil organic matter stocks and changes in its quality, however, with 15 and 20 years can be noted a suficiente incremente of C in SOM maintaining to obtain higher CMIs than CE and HT30.

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Tmimi, Mohammed. "Nouvelle approche pour lien série en technologie FD-SOI 28 nm CMOS avancée et au-delà." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT079.

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Dans le cadre de l’échange massif de données numériques, la solution du lien série est largement utilisée dans les systèmes électroniques. Dans ce cadre, il existe une course permanente pour accroître le débit de transfert de données. Notamment les efforts portent sur l’amélioration de l’efficacité énergétique du système et l’optimisation des canaux de transmission. Cependant la contrainte physique du canal de transmission est une donnée majeure dans cette approche de transmission de données à haut débit.Les méthodes standard de transmission intra-puces point à point utilisent la bande de base, le délai de transmission dans cette bande se situe autour de 40 ps/mm, acceptable pour des distances courtes inférieures au mm. Or, pour un lien de quelques mm, la solution standard d’utiliser des routeurs n’est plus optimale quant à la consommation et au temps de transfert dus à la propagation du signal en bande de base. En conséquence, un changement de paradigme est nécessaire afin de réduire ce délai.Aujourd’hui, les recherches sont très actives concernant l’intégration monolithique de lien série, ce qui permet d’avoir une excellente base de concepts et de solutions. Dans la littérature, on note ainsi plusieurs solutions, la principale étant la transmission sans-fil intra-puces « wireless on-chip (WiNOC) », où des antennes intra-puces sont utilisées pour transmettre les données. On peut également noter l’utilisation de l’optoélectronique pour transmettre avec un délai minimal. Il en résulte un changement de processus.Dans ce travail, on vise les liens de quelques mm de long, où aucune des solutions précédentes n’est optimale, soit à cause du temps de propagation soit à cause de la complexité de l’implémentation due au changement du procédé. Cette solution est complémentaire aux solutions existantes et nous pensons qu’elle permet de résoudre certains de leurs problèmes et prolonger la durée de vie des architectures réseau sur puces (NoC) existantes.On investigue la transmission en bande millimétrique (à 60 GHz) où la vitesse de propagation du signal est autour de 1,5.10^8 m/s, impliquant un délai minimal (7 ps/mm). Par ailleurs, différentes modulations seront investiguées pour augmenter le débit et exploiter efficacement les bandes passantes disponibles à ces fréquences. On a choisi la modulation duobinaire pour son avantage en termes de compression du spectre, ce qui nous a permis de doubler le débit utilisé pour une même bande passante, ainsi que pour sa simplicité de modulation/démodulation. Dans notre cas, on utilise 5 GHz de bande pour transmettre un signal de 10 Gbps.Cette approche théorique a été modélisée pour ensuite la comparer aux différents systèmes à l’état de l’art ; un débit maximal de 14 Gbps a été atteint avec un taux d’erreur inférieur a 10^(-12) en simulation. Un démonstrateur sur silicium à 10 Gbps a été conçu sur la base de la technologie CMOS avancée 28 nm FD-SOI de STMicroelectronics. Le transmetteur, le récepteur ainsi que des lignes de propagation d’une longueur de 4.6 mm ont été implémentés, les résultats de mesures seront publiées dans de futurs travaux. Les simulations ont montré que nous avons atteint un débit plus élevé (au moins le double) que l’état de l’art, pour une surface plus faible et une efficacité énergétique comparable.Nous avons également proposé d'utiliser la même approche pour les canaux d’interposeurs afin de connecter des chiplets avec un délai minimal. Nous étudions son application pour un interposeur passif en silicium en technologie BiCMOS 130 nm, mais il peut également être utilisé pour les circuits actifs. Nous avons connecté deux puces en technologie 28 nm FD-SOI à une distance de 7 mm et obtenu un taux d’erreur binaire inférieur à 10^(-12) avec une latence de 7 ps / mm en simulation
The global internet traffic exceeded the zettabyte marker in 2016. Since then, internet traffic proliferated with a compound annual growth rate of 26%; and is expected to continue its astronomical growth rate. This perpetual growth has significant implications for networking technologies. Researchers anticipated their limits and managed to stay ahead of the curve by innovating and optimizing all data transfer levels. In that context, this work focuses on on-chip data transfer, acknowledging that communication energy efficiency is one of the integrated circuits near future bottlenecks, as the gap between the computation energy and on-die IC energy grows.Evidently, improvements have to be made to the existing links solutions; higher data rates must be reached while considering the energy efficiency and the circuit complexity. Furthermore, with the increasing data rates, signal integrity problems arise due to channel imperfections. Although transistor scaling provided higher density packing of devices and faster transistors, it did not benefit the interconnections performance since it resulted in higher wires density. Wires are more sensitive to their environment than active devices, that is, closer wires are more sensible to crosstalk and longer delay due to the wire's intrinsic delay. Delay is a critical metric for data transmission. In this work, we developed a high data-rate low delay solution for long-range on-chip serial links. The developed solution is complementary to the massively employed existing solutions. We believe it will help solve some of their issues and extend the existing Network on chips architectures lifetime.We start this work by introducing the standard and emerging on-chip interconnect solutions, then discussing their advantages and challenges. The chosen RF interconnects technique is most suitable for our requirements, mainly due to low delay, high available bandwidths, and CMOS process compatibility/friendliness. This approach requires transmitting the data at high frequencies instead of the baseband, that is, up-converting the data signal before transmitting it through the transmission lines. In practice, transmission lines behave differently at baseband and high-frequencies. In particular, both distortion and delay are much lower at high-frequencies. These two properties are essential for our work; low distortion implies that high signal integrity is reached without equalization or error-correcting codes, up to 14 Gbps in the proposed study. At least four times lower than baseband delay, the high-frequency low delay property signifies that long distances across the chip can be crossed in less time.We believe this approach is most beneficial for distances longer than a couple of mm and up to twentieth mm.Bandwidth at higher frequencies (60 GHz in our case) is a valuable commodity. To take full advantage of it, we used duobinary modulation to double the data rate. This spectrum compression relaxes the RF components constraints such as linearity; The chosen modulation simplifies the demodulation where a simple envelope detector is used to recover the data.A 10 Gbps prototype chip was designed and fabricated in the advanced 28 nm FD-SOI technology from STMicroelectronics. In this work, we explained the design process of the transceiver (composed of a transmitter, a receiver, and a 4.6mm channel). The simulation results showed that we reached a higher data rate (at least double) than the state of the art, for a smaller area and a comparable energy efficiency. The post-layout simulation resulted in a BER lower than 10^(-12). The measurement results will be published in future works.We also proposed to use the same approach for interposer channels to connect chiplets with minimal delay. We study its application for a 130 nm BiCMOS technology passive silicon interposer. We connected two 28 nm FD-SOI chiplets at a 7-mm distance and achieved a BER lower than 10^(-12) with a 7 ps/mm delay in simulations

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Sharif, Khurram Jahangir. "Trust as a determinant of upstream and downstream long-term orientation in SME business relationships." Thesis, Kingston University, 2003. http://eprints.kingston.ac.uk/20720/.

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Over the last two decades, business-to-business (b-to-b) relationships have received considerable attention through the recognition that it is possible to increase profitability through relational (exchange governed by norms of long-tern co-operation, mutual satisfaction, trust and open communication) rather than discrete (exchange that is arms-length, short-term and centred on self-interest) exchanges. One of the construct's which has received considerable attention within the b-to-b exchange process is trust. Several studies have highlighted trust as a central construct in understanding, building, maintenance and growth of business relationships. The role of trust in business exchanges between large organisations has been extensively researched and reported. However, very little research has been undertaken in terms of the impact of trust in SME relationships. The proposed research attempts to contribute towards this omission. An approach utilising a modification of Ganesan's (1994) model of retailer's and, vendor's long-tern orientation that looks at the antecedents of trust and their effect on long-term orientation is adopted. Change to the model, as suggested by Ganesan (1994), is incorporation of behavioural antecedents (relational norms) of trust. The result is a testable model that has been applied for assessing the relative impact of cognitive and behavioural trust on the upstream (supplier) and downstream (customer) long-term orientation (LTD) in SMEs when they are engaged in overall/mutual, symmetric and asymmetric exchanges. Hence the model is tested within the relational set-up that involved 8MEs and other partner organisations (i.e., SMEs and Medium-to-large organisations). The analysis conducted at three relational levels showed the following key outcomes: 1. The overall upstream and downstream analysis (where SME was involved in both symmetric and asymmetric relationships) indicates a major overlap between the proposed research findings and reported trust findings (profoundly related to large organisation studies). There was clear evidence that both cognitive and behavioural trust lead to LTO. 2. Within the symmetric (i.e., SME-to-SME) relationship analysis there was clear evidence that it was the presence of cognitive trust that led to LTO. Therefore relationships were largely driven by the credible proof (i.e., reputation and skill) of suitability. 3. In asymmetric (i.e., Small to Medium-to-large organisation) relationship analysis there was no clear evidence of either cognitive or behavioural trust being determinant of LTO. However both transaction specific investments (cognitive trust antecedent) and flexibility (behavioural trust antecedent) had a significant effect on inter-organisational trust.

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Diniz, Danielle Dornellas. "A interação no ensino a distância sob a ótica dos estilos de aprendizagem." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18140/tde-20122007-141314/.

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As pessoas têm diferentes preferências no aprender, que acabam se refletindo nas suas diversas características acadêmicas e profissionais. Há muito tempo se procura uma resposta para a pergunta: \"por que nas mesmas condições de ambiente e forma de ensino, dois estudantes de mesmo nível intelectual, possuem níveis de aprendizagem diferentes?\". Parte da resposta pode ser encontrada nos estilos de aprendizagem, os diferentes modos pelos quais as pessoas percebem e processam as informações. Entender os diferentes estilos de aprendizagem é um passo importante para favorecer a individualidade, tirar proveito das habilidades e também identificar os modos menos preferidos de aprender. Esse autoconhecimento é fundamental ao tratamos do ensino a distância (EaD), que requer que os próprios alunos se organizem e otimizem seu próprio aprendizado. A partir do momento em que conhecem suas preferências, os estudantes têm a possibilidade de dirigir sua aprendizagem nessa direção. Por outro lado, o professor também tem subsídios para planejar atividades e disponibilizar recursos que atendam a uma variedade maior de alunos, diminuindo assim a taxa de desistência e mantendo a motivação, uma vez que a mesma também está intimamente ligada com o nível de comunicação e interação na sala virtual. Assim, o objetivo deste projeto é mapear os estilos de aprendizagem de estudantes matriculados em um curso de licenciatura em Computação na modalidade EaD e analisar a influência desse construto na interação desses estudantes no fórum. Para a coleta dos estilos de aprendizagem dos 36 alunos foram usados os instrumentos desenvolvidos por Felder e Soloman (1991) e o de Keirsey e Bates (1984), ambos traduzidos para o português. Os resultados identificam uma distribuição dos estilos de aprendizagem bem característica para alunos de um curso de licenciatura em Computação a distância. Além disso, as correlações entre esses estilos de aprendizagem e a interação na sala virtual na ferramenta fórum demonstram que os alunos ativos (FELDER; SOLOMAN, 1991) foram os que possuíram níveis de maior interação e de forma oposta, os racionais (KEIRSEY; BATES, 1984) estavam entre os que menos participaram das discussões. Verificou-se também uma predominância de indivíduos ativos dentre os que responderam aos tópicos de forma objetiva (critério de interação C1), assim como uma tendência de indivíduos dessa dimensão relacionarem mais os assuntos discutidos (critério de interação C2). Dessa forma, os resultados confirmam que o modo como os alunos interagem no fórum tem relação com seus estilos de aprendizagem, os quais podem auxiliar na proposição de atividades que motivem e incrementem a participação na sala virtual.
People have different preferences in learning, that reflect in their several professional and academic characteristics. Long ago it is looking for an answer to the question: \"why, in the same conditions of environment and education form, two students of same intellectual level, have different learning levels?\". Part of the reply can be found in the learning styles, the different ways for which people perceive and process the informations. Understanding the different learning styles is an important step to favor the individuality, to make good use of the abilities and also identify the ways less preferred to learn. This self-knowledge is fundamental when we are dealing with the long-distance education, which request that the own students organize themselves and optimize their own learning. From the moment when they know their preferences, the students have the possibility to direct their learning in this direction. On the other hand, the teacher also has subsidies to plan activities and to arrange resources for a bigger variety of students, thus diminishing the desistance rate and keeping the motivation, a time that this one is also deeply connected to the level of communication and interaction in the virtual room. Thus, the objective of this project is to map the learning styles of the students registered in a computer science course in long-distance education, and to analyze the influence in these students\' interaction in the forum. For the collection of the learning styles of the 36 students, it had been used the tools developed by Felder and Soloman (1991) and the Keirsey and Bates\' (1984), both translated into portuguese. The results identify a distribution of the learning styles well characterized for students of a long-distance bachelor course in Computer Science. Moreover, the connections between these learning styles and the interaction in the virtual room in the forum tool show that the active students (FELDER; SOLOMAN, 1991) were who had the levels of bigger interaction and, in contrast, the thinkers students (KEIRSEY; BATES, 1984) were among the ones that had less participated in the debates. It was also verified a predominance of active individuals between who had answered to the topics objectively (interaction criterion C1), as well as a trend of individuals of this dimension relate more the argued subjects (interaction criterion C2). This way, the results confirm that the way as the students interact in the forum has a relation with their learning styles, which can assist in the proposal activities that motivate and develop the participation in the tools of the virtual classroom.

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Dinger, Florian [Verfasser]. "On long-term variations in the BrO/SO2 molar ratios in volcanic gas plumes / Florian Dinger." Mainz : Universitätsbibliothek Mainz, 2019. http://d-nb.info/1196371946/34.

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Goodwin, William Brandon. "Controlled modulation of short- and long-range adhesion of microscale biogenic replicas." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54842.

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The generation of nanostructured microscale assemblies with complex, three-dimensional (3-D) morphologies possessing multicomponent inorganic compositions tailored for adhesion is of considerable scientific and technological interest. This dissertation demonstrates that self-assembled 3-D organic templates of biogenic origin can be converted into replicas comprised of numerous other functional nanocrystalline inorganic materials and, further, how such replicas can tailored for adhesion. Nature provides a spectacular variety of biologically-assembled 3-D organic structures with intricate, hierarchical (macro-to-micro-to-nanoscale) morphologies designed for particle adhesion. The conformal coating of such structurally-complex biotemplates with synthetic materials provides a framework for chemical transformation of other, complex synthetic organic templates and the basis to study imparted adhesion properties. Three specific research thrusts are detailed in this document. First, freestanding magnetite (Fe3O4) replicas of bio-organic templates are synthesized via a layer-by-layer (LbL) wet chemical deposition process and subsequent morphology-preserving thermal treatments to allow for structures with tailorable long-range magnetic adhesion. Second, freestanding spinel ferrite replicas of bio-organic templates are synthesized (via LbL coating and thermal treatment) for grain size controlled long-range magnetic adhesion and short range van der Waals adhesion. The final research thrust focuses on the use of a low temperature (≤ 250°C) wet-chemical based process to convert bioorganic templates into magnetically-coated structures retaining both the size and morphology of the template. The rate-limiting kinetic mechanism(s) of the partial reduction of the inorganic coatings have been examined via quartz crystal microbalance analysis. The effects of the coating micro/nanostructure on magnetic behavior and on surface adhesion, have been investigated.

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Reis, Hugo Leonardo Castilhos dos. "Sobre a luz e o silêncio : o plano de longa duração e a dinâmica do som no cinema de Carlos Reygadas." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/5622.

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Universidade Federal de Minas Gerais
This work aims to discuss the cinema of Carlos Reygadas, with the focuses on the importance of sound and its dynamics within the long duration take, a procedure that strongly characterizes the style of this director. Initially, excerpts from films Japón (2002), Battle in Heaven (2005) and Silent Light (2007) were analyzed to highlight the formation of a stylistic corpus and a predominantly contemplative and sensory conception of cinema. Then we elected Silent Light as a conductive thread of a broader analysis in relation to the main crop. Therefore, we had as main references studies by David Bordwell (2008) on traditional directors of the plan-sequence, as well as the categories and theoretical assumptions of Michel Chion (1994, 2009) on the uses of sound in cinema.
Esta dissertação tem por objetivo discutir o cinema de Carlos Reygadas, sob um recorte que se concentra especificamente na importância do som e de sua dinâmica no interior dos planos de longa duração, procedimento que caracteriza fortemente o estilo deste diretor. Inicialmente, trecho dos filmes Japón (2002), Batalha no Céu (2005) e Luz Silenciosa (2007) foram analisados para salientar a conformação de um corpus estilístico e de uma concepção de cinema de caráter predominantemente contemplativo e sensorial. Em seguida, elegemos Luz Silenciosa como o fio condutor de uma análise mais abrangente em relação ao principal recorte. Para tanto, tivemos como principais referências os estudos de David Bordwell (2008) sobre tradicionais diretores do plano-sequência, bem como as categorias e pressupostos teóricos de Michel Chion (1994; 2009) sobre usos do som no cinema.

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Dreyer, Sule. "The effect of minimalist shoe training on the neuromuscular control of recreational distance runners." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86309.

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Thesis (MScSportSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Neuromuscular control (NMC) plays a critical role in dynamic movement regulation such as running (Nyland et al., 2011) and injury prevention (Hübcher et al., 2010). This experimental study set out to determine whether an eight-week minimalist shoe training program influences NMC in recreational distance runners. Eleven experimental (EXP) (5 women; 6 men) (age 23.4 ± 2.98 yrs; VO2max 43.55 ± 5.04 ml.min-1.kg-1; BMI 22.61 ± 3.08 kg.m2; Training 17 ± 5km.w-1) and 12 control (CON) runners (7 women; 5 men) (age 25.42 ± 5.57 yrs; VO2max 43.67 ± 4.38 ml.min-1.kg-1; BMI 22.38 ± 3.12 kg.m2; Training 18 ± 6km.w-1) randomly completed an eight-week training program in either minimalist shoe (EXP) or their usual trainers (CON). Neuromuscular control components were measured before and after the intervention i.e. postural sway (Balance Biodex®), using the Athletic Single Leg (ASL) and modified Clinical Test of Sensory Integration and Balance (mCTSIB) tests, joint position sense (JPS) using joint angle reproduction tests (Biodex® Isokinetic Dynamometer), frontal and sagittal planes isokinetic strength testing, lower body electromyography (EMG) and kinematic measurements while participants ran on a treadmill. Plantar-dorsiflexion (PF/DF) or inversion eversion (IN/EV) proprioception did not differ between groups (p > 0.05). In selected trials EXP showed less deterioration in IN/ EV foot position error, when compared to CON, with medium to large practical significance. Athletic Single Leg scores for non-dominant (p < 0.01) and dominant M/L (p = 0.05) sway, and dominant overall sway (p = 0.04) improved in CON, with marked differences between genders. Dorsiflexor strength improved for 30∘.sec-1 and 60∘.sec-1speeds in CON (p < 0.01 & p = 0.04, respectively) and in the slower speed for EXP (p = 0.04). Plantar-flexion (PF) strength improved in EXP men (30∘.sec-1 p = 0.02; 60∘.sec-1 p = 0.02), while EXP women demonstrated a 7% deficit. At initial contact PF increased in EXP (8km.h-1 p = 0.01; 10km.h-1 p = 0.01; 12km.h-1 p = 0.01), with women showing a greater change in ankle angle (8km.h-1 p = 0.03; 10km.h-1 p = 0.02; 12km.h-1 p = 0.01) compared to men (8km.h-1 p = 0.05; 10km.h-1 p = 0.06; 12km.h-1 p = 0.05). Greater knee flexion (8km.h-1 ES = 0.64; 10km.h-1 ES = 0.49; 12 km.h-1 ES = 0.51) in EXP. Plantar-flexor pre-activation improved in EXP women, while co-activation improved in EXP men and total activation improved in both genders.Results suggest that women may require more time to transition into minimalist shoes. While minimalist shoes may moderately reduce foot position error, improve strength and muscle activation patterns, excessive plantar flexor muscle damage may reduce strength and muscle spindle proprioceptive feedback.
AFRIKAANSE OPSOMMING: Neuromuskulêre beheer (NMC) speel ‘n kritieke rol in dinamiese beweginsregulasie, soos met hardloop (Nyland et al., 2011) en beseringsvoorkoming (Hübscher et al., 2010). Hierdie eksperimentele studie het uit gesit om te bepaal of ‘n agt-week minimalistiese skoen oefenprogram NMB kan beïnvloed in rekreasie langafstand atlete. Elf eksperimentele (EXP) (5 vrouens, 6 mans) (ouderdom 23.4 ± 2.98 jr; VO2maks 43.55 ± 5.04 ml.min-1.kg-1; BMI 22.61 ± 3.08 kg.m2; Oefening 17 ± 5km.w-1) en twaalf kontrole (CON) hardlopers (7 vrouens, 5 mans) (ouderdom 25.42 ± 5.57; VO2maks 43.67 ± 4.38 ml.min-1.kg-1; BMI 22.38 ± 3.12 kg.m2; Oefening 18 ± 6 km.w-1) het lukraak ‘n agt-week oefenprogram voltooi, óf in minimalistiese skoene (EXP) of in hul gewone hardlooptekkies (CON). Neuromuskulêre beheer komponente was gemeet voor en na die intervensie i. e. posturale wieg (Balans Biodex®), met gebruik van Atletiese Enkelbeentoets (ASL) en die gemodifiseerde Kliniese Toets van Sensoriese Integrasie en Balans (mCTSIB), gewrigs posisie bewustheid (Biodex® Isokinetiese Dinamometer), frontale en sagitalle vlak isokinetiese kragtoetsing, onderlyf elektromiografie (EMG) en biomeganiese metings terwyl deelnemers op ‘n trapmeul gehardloop het. Plantaar dorsifleksie (PF/DF) of inversie eversie (IN/EV) propriosepsie het nie verskil tussen groepe nie (p > 0.05). In selektiewe proewe het EXP IN/ EV ‘n verminderde afname gehad in foutiewe voet posisieplasings, in vergelyking met CON, terwyl medium na groot praktiese betekenisvolle verskille. . Atleet enkel been toets tellings vir nie-dominant (p=0.001) en dominante M/L (p = 0.05) wieg, en dominant algehele wieg (p = 0.04) het verbeter in CON, met gemerkte verskille tussen geslagte. Dorsifleksor krag het verbeter vir 30∘.sec-1 en 60∘.sec-1spoed in CON (p = 0.01 en p = 0.04, onderskeidelik) en in die stadiger spoed vir EXP (p = 0.04). Plantaarfleksie (PF) krag het verbeter in EXP mans (30∘.sek-1 p = 0.02; 60∘.sek-1 p = 0.02), terwyl EXP vrouens ‘n 7% tekort gedemonstreer het. By initïele kontak het PF toegeneem in EXP (8km.h-1 p = 0.01; 10km.h-1 p = 0.01; 12km.h-1 p = 0.01), met vrouens wat ‘n groter verandering getoon het (8km.h-1 p = 0.03; 10km.h-1 p = 0.02; 12km.h-1 p = 0.01), in vergelyking met mans (8km.h-1 p = 0.05; 10km.h-1 p = 0.06; 12km.h-1 p = 0.05). Groter kniefleksie (8km.h-1 ES = 0.64; 10km.h-1 ES = 0.49; 12 km.h-1 ES = 0.51) in EXP. Plantaarfleksie pre-aktivering het verbeter in EXP vrouens, terwyl ko-aktivering verbeter het in EXP mans, en totale aktivering verbeter het in beide geslagte.Hierdie resultate stel voor dat vrouens moontlik meer tyd sal vereis om na minimalistiese skoene oor te skakel. Terwyl minimalistiese skoene matige verbetering in foutiewe voetposisieplasing, verbeterde krag en spieraktiveringspatrone kan veroorsaak, kan oormatige plantaarfleksie spierskade krag en spierspoel proprioseptiewe terugvoer ook verminder.

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Alvarado-Ochoa, Soraya Patricia. "CHARACTERIZATION OF SOIL CARBON STABILIZATION IN LONG-TERM ROW-CROPPED AGRO-ECOSYSTEMS." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/93.

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Soil organic matter (SOM) is a dynamic soil property, sensitive and responsive to many factors. The possibility of increasing soil carbon (C) sequestration by changing land use and management practices has been of great interest recently due to concerns with global changes in the atmospheric carbon dioxide (CO2) balance. Nonetheless, as a result of the complex dynamics of SOM, there is still the need for SOM characterization procedures capable of monitoring SOM stabilization, taking into account all the factors involved. This study characterized SOM stabilization as affected by management practices in three long-term field experiments, considering physical, chemical and biological components. The field experiments are located near Lexington, Kentucky, on a Maury silt loam (fine, mixed, mesic Typic Paleudalfs). The first experiment evaluates tillage and nitrogen (N) rate effects. The second experiment studies manure and N rate effects. The third experiment evaluates the five corn components of three crop rotations [continuous (monoculture) corn, corn-wheat/double crop soybean, and hay-hay-corn-corn-corn]. Soil organic matter content, stability, and composition, for physically separated fractions, were assessed using δ13C natural abundance and diffuse reflectance Fourier transformed infrared (DRIFT) spectroscopy. In addition, management effects on microbial biomass and microbial function as indicated by phenol oxidase enzyme activity were evaluated. The results indicate that management practices affect SOM content, stability, and composition, and these effects differ by the soil aggregate fraction. No-tillage (NT), N fertilization, manure application and increased corn in crop rotations enhanced SOM levels. However, the effect of NT was observed mainly at the soil surface. Soil organic matter storage was determined by the aggregate size distribution. The proportion of recently deposited C was generally positively related to aggregate size, especially for the first and third experiments. Most of the recently deposited C was stabilized in microaggregates within macroaggregates, across the management treatments and field experiments. In addition, this fraction consistently exhibited low to medium SOM reactivity. These results suggest that SOM stabilization, as influenced by management practices, required achieving a specific composition and location within the soil matrix. This implies that soil C forms and aggregate size and stability are closely interrelated.

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Martin, Chrsitelle. "Etude du comportement à long terme des vitrocristallins à base de zirconolite." Montpellier 2, 2002. http://www.theses.fr/2002MON20144.

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Bergström, Gustaf, Johan Bäckbro, and Christofer Johansson. "Can a Gazelle Run Forever? : A Study of Rapid Growth's Affect on SMEs' Ability to Grow in a Long-Term Perspective." Thesis, Jönköping University, JIBS, Business Administration, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-79.

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Abstract:

Bakgrund

Gaseller är små- och medelstora företag (SME: s) med hög tillväxttakt som konstant skapar nya arbetstillfällen och har en positiv inverkan på den svenska ekonomin. Många författare anser att en differentieringsfokus är mest lämpligt för SME: s för de ska kunna skapa konkurrensfördelar och tillväxt. Denna fokus är ett strategiskt val som underbyggs av innovationsförmåga. Dock, när konkurrensfördelen leder till snabb tillväxt så uppstår växtvärk. Följaktligen, vad händer med SME: s innovativa förmåga under snabb tillväxt och vidare, hur påverkar detta SME: s förmåga att uppnå långsiktig tillväxt?

Syfte

Syftet med denna uppsats är att undersöka hur snabb tillväxt i SME: s påverkar deras förmåga att uppnå långsiktig tillväxt.

Metod

För att uppnå syftet med denna uppsats så har en jämförande analys utförts baserat på en holistisk undersökning av ett flertal case. Undersökningen inkluderade fem tillverkande SME: s belägna Jönköpings län som alla mottagit utmärkelsen ”Gasell” från den svenska finansiella tidningen Dagens Industri. Denna utmärkelse de-las ut till företag som fördubblat sin omsättning under en period av tre år samtidigt som de haft positiv tillväxt och en stabil ekonomisk situation (DI, 2005).

Slutsats

Efter att ha analyserat de empiriska resultaten med passande teori kunde några övergripande slutsatser dras. Studien kunde visa att den växtvärk som ofta uppstår i SME: s som genomgår en period av snabb tillväxt påverkar den interna organisationen att anpassa sig till ökad komplexitet och resursbrist på ett sätt som har en negativ påverkan på deras innovativa förmåga. Det fanns också tendenser att detta i sin tur hade negativ effekt på SME: s förmåga att växa i ett långsiktigt perspektiv.

Background

Gazelles are high growth Small Medium sized Enterprises (SMEs) that constantly are creating new job-opportunities and contributing positively to the Swedish economy. In order to achieve competitive advantage and growth for SMEs, several authors argue that a focus on differentiation is most suitable, which is a strategic approach mainly underpinned by innovative ability. However, when competitive advantage leads to rapid growth certain growing pains occur. Thus, when SMEs are growing rapidly, what happens to their innovative ability and further how does this affect their long-term growth?

Purpose

The purpose of this thesis is to explore how rapid growth in SMEs affects their ability to attain long-term growth.

Method

In order to fulfil the purpose, a comparison analysis has been conducted based on a holistic multi-case study. The cases included five manufacturing SMEs in Jönköping County, of which all have been appointed the Gazelle-award issued by the Swedish financial newspaper Dagens Industri. This award is given to companies that have doubled its turnover in three years, while simultaneously having positive growth and a stable economical situation.

Conclusion

After analysing the empirical results with appropriate theories, some main conclusions could be reached. The study could demonstrate that the growing pains, often emerging in SMEs experiencing rapid growth, influence the organization to adapt itself to the increasing complexity and resource constraints in a way that has a negative affect on the their innovative ability. There was further some support that this in turn had a negative affect on SMEs ability to grow in a long-term per-spective.

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Brunelli, Marcela Cristina 1982. "Índice SPAD e trocas gasosas ao longo do dia para diferenciação de cana-de-açúcar sob deficiência hídrica /." Botucatu, 2014. http://hdl.handle.net/11449/113789.

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Orientador: Marcelo de Almeida Silva
Banca: Elizabeth Orika Ono
Banca: Claudia Moura dos Santos
Resumo: A cana-de-açúcar (Saccharum spp.) é uma cultura globalmente importante não só para a produção de açúcar como também para a produção de bioenergia. A seca é um dos fatores ambientais mais importantes que limita a produção mundial de cana-de-açúcar. Devido à natureza irregular das chuvas, os produtores têm certa dependência da irrigação para manter as metas de produção. Entretanto, a água para irrigação é limitada, e deve ser utilizada racionalmente, não só para reduzir o desperdício, mas também pela redução dos custos de produção e manutenção de produtividade. O desenvolvimento e estudo de variedades tolerantes ao estresse hídrico é crucial para a produção em áreas onde a água é escassa ou limitada. É verificado, em algumas culturas, que a concentração de clorofila e o esverdeamento das folhas se correlacionam com tolerância à deficiência de água, porém essas variáveis recebem influência de diferentes condições ambientais,rever tais como irradiância, temperatura do ar e condições hídricas da folha, que normalmente ocorrem grandes variações durante o dia. O trabalho teve como objetivo avaliar a influência do estresse hídrico e do horário de avaliação sobre a leitura do índice SPAD e das trocas gasosas em cana-de-açúcar. O experimento foi conduzido em casa de vegetação, onde foram avaliadas as variedades RB867515 e RB855453, sob ou não deficiência hídrica em relação a índice SPAD, conteúdo de clorofila total, temperatura foliar, potencial hídrico foliar (ψw), taxa de assimilação de CO2, máxima eficiência fotoquímica do fotossistema II (Fv/Fm), radiação fotossinteticamente ativa, temperatura e umidade do ar na folha +1 em quatro horários do dia (7, 10, 13 e 16h). Para tanto, constatou-se a variação do índice SPAD durante o dia, obtendo uma tendência decrescente com o passar das horas, tendo o conteúdo de ...
Abstract: The sugarcane (Saccharum spp.) is a globally important not only for sugar production but also for the production of bioenergy crop. The drought is one of the most important environmental factors limiting the global production of sugarcane. Due to the irregularity rainfall, growers have some dependence of irrigation to maintain production targets. However, the water irrigation is limited and must be rationally utilized not only to reduce wastage, but also to reduce the costs of production and maintenance of productivity. The study and development of tolerant varieties to water stress is crucial for production in areas where water is scarce or limited. It is found, in some cultures, the concentration of chlorophyll and the greening of leaves correlate with tolerance to water stress, but these variables are influenced by different environmental conditions, such as irradiance, air temperature and leaf water conditions, that occur in a large variation during the day. The study aimed to evaluate the influence of water stress and time of assessment on reading the SPAD index on sugarcane. The experiment was conducted in a greenhouse, where RB867515 and RB855453 varieties were evaluated, by water stress or not water stress, in relation to SPAD index, total chlorophyll content, leaf temperature, leaf water potential (ψw), CO2 rate assimilation, maximum quantum efficiency of photosystem II (Fv/Fm), photosynthetic active radiation, temperature and humidity on +1 leaf in four times of the day (7, 10, 13 and 16 hours). Thus, we found the variation of SPAD index during the day, that showed a decreasing tendency over the hours, and it was verified that the total chlorophyll content extracted ranging in the same way. Overall, the most significant results of physiological parameters, except for stomatal conductance, for the maximum quantum efficiency of photosystem II (Fv/Fm) and for the water use efficiency ...
Mestre

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Rego, Bruna Turino. "Avaliação do comportamento mecânico de nanocompósito de PEEK/nHA sob curta e longa duração para aplicação como biomaterial." Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/868.

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Universidade Federal de Minas Gerais
The main objectives of this dissertation were to study the short (tensile and impact) and long-term (fatigue) mechanical behavior of nanocomposites of poly(ether-ether-ketone), PEEK, with nanohydroxyapatite, nHA, for application as biocompatible materials. First of all, a preliminary study was conducted to determine the influence of the addition of nHA in the rheological, thermal and dynamic mechanical properties of PEEK, in order to choose an optimal formulation for large-scale preparation. The chosen composition with 10wt% of nHA was prepared by melt mixing in a co-rotating twin screw extruder. The resulting structure and dispersion were characterized by scanning electron microscopy (SEM) and rheological properties. Subsequently, the materials (PEEK and PEEK/nHA nanocomposite) were injection molded at 3 different conditions by varying the flow rate. The resulting morphologies were evaluated by polarized light optical microscopy (PLOM) and the degree of crystallinity of the samples was evaluated by differential scanning calorimetry (DSC) and wide angle X-ray scattering (WAXS). The mechanical properties of tensile, impact and fatigue of PEEK and nanocomposite were measured and correlated with the results of dynamic mechanical thermal analysis (DMTA) and the resulting morphology. It was found that the variation of the injection conditions did not change the materials properties significantly; however, the obtained long and short-term mechanical properties of the nanocomposite were within the range of cortical bone properties and, therefore, the nanocomposite can mechanically be used for medium load bearing implant applications, due to their limited modulus. Finally, tests with adult stem cells to determine in vitro biological response of the biomaterial were performed, which indicated that these cells proliferated faster in PEEK/nHA, indicating that the biological response is most favorable to the nanocomposite than to pure PEEK.
Esta dissertação teve como principal objetivo estudar as propriedades mecânicas de curta (tração e impacto) e longa duração (fadiga) de um nanocompósito de poli(éter-éter-cetona), PEEK, com nanohidroxiapatita, nHA, para aplicação como material biocompatível. Primeiramente, foi realizado um estudo preliminar para determinar a influência da adição da nHA nas propriedades reológicas, térmicas e dinâmico-mecânicas do PEEK, com o objetivo de escolher uma formulação ideal para preparo em grande escala do nanocompósito. Em seguida, a composição escolhida com 10% em massa de nHA foi preparada via mistura no estado fundido em uma extrusora de rosca dupla co-rotacional. A estrutura resultante e a dispersão foram caracterizadas por microscopia eletrônica de varredura (MEV) e por propriedades reológicas. Posteriormente, os materiais (PEEK/nHA e PEEK puro) foram moldados por injeção em 3 condições diferentes, variando-se a vazão. As morfologias obtidas foram avaliadas por microscopia ótica de luz polarizada (MOLP) e o grau de cristalinidade das amostras foi avaliado por calorimetria exploratória diferencial (DSC) e por difração de raios-X de alto ângulo (WAXS). As propriedades mecânicas de tração, impacto e fadiga do PEEK e do nanocompósito foram medidas e correlacionadas com os resultados de análise térmica dinâmicomecânica (DMTA) e com a morfologia resultante. Verificou-se que a variação nas condições de injeção não promoveram diferenças significativas nas propriedades dos materiais; no entanto, as propriedades mecânicas de curta e longa duração obtidas para o nanocompósito estavam dentro da faixa de propriedades do osso cortical sendo, portanto, o nanocompósito compatível mecanicamente para aplicações como implantes que não envolvam alto suporte de carga, devido à sua limitação de módulo elástico. Por fim, foram realizados testes com células-tronco adultas para determinar a resposta biológica in vitro do biomaterial produzido, os quais indicaram que a proliferação destas células ocorreu de forma mais rápida no PEEK/nHA, indicando que a resposta biológica é mais favorável ao nanocompósito do que ao PEEK puro.

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36

Brunelli, Marcela Cristina [UNESP]. "Índice SPAD e trocas gasosas ao longo do dia para diferenciação de cana-de-açúcar sob deficiência hídrica." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/113789.

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A cana-de-açúcar (Saccharum spp.) é uma cultura globalmente importante não só para a produção de açúcar como também para a produção de bioenergia. A seca é um dos fatores ambientais mais importantes que limita a produção mundial de cana-de-açúcar. Devido à natureza irregular das chuvas, os produtores têm certa dependência da irrigação para manter as metas de produção. Entretanto, a água para irrigação é limitada, e deve ser utilizada racionalmente, não só para reduzir o desperdício, mas também pela redução dos custos de produção e manutenção de produtividade. O desenvolvimento e estudo de variedades tolerantes ao estresse hídrico é crucial para a produção em áreas onde a água é escassa ou limitada. É verificado, em algumas culturas, que a concentração de clorofila e o esverdeamento das folhas se correlacionam com tolerância à deficiência de água, porém essas variáveis recebem influência de diferentes condições ambientais,rever tais como irradiância, temperatura do ar e condições hídricas da folha, que normalmente ocorrem grandes variações durante o dia. O trabalho teve como objetivo avaliar a influência do estresse hídrico e do horário de avaliação sobre a leitura do índice SPAD e das trocas gasosas em cana-de-açúcar. O experimento foi conduzido em casa de vegetação, onde foram avaliadas as variedades RB867515 e RB855453, sob ou não deficiência hídrica em relação a índice SPAD, conteúdo de clorofila total, temperatura foliar, potencial hídrico foliar (ψw), taxa de assimilação de CO2, máxima eficiência fotoquímica do fotossistema II (Fv/Fm), radiação fotossinteticamente ativa, temperatura e umidade do ar na folha +1 em quatro horários do dia (7, 10, 13 e 16h). Para tanto, constatou-se a variação do índice SPAD durante o dia, obtendo uma tendência decrescente com o passar das horas, tendo o conteúdo de ...
The sugarcane (Saccharum spp.) is a globally important not only for sugar production but also for the production of bioenergy crop. The drought is one of the most important environmental factors limiting the global production of sugarcane. Due to the irregularity rainfall, growers have some dependence of irrigation to maintain production targets. However, the water irrigation is limited and must be rationally utilized not only to reduce wastage, but also to reduce the costs of production and maintenance of productivity. The study and development of tolerant varieties to water stress is crucial for production in areas where water is scarce or limited. It is found, in some cultures, the concentration of chlorophyll and the greening of leaves correlate with tolerance to water stress, but these variables are influenced by different environmental conditions, such as irradiance, air temperature and leaf water conditions, that occur in a large variation during the day. The study aimed to evaluate the influence of water stress and time of assessment on reading the SPAD index on sugarcane. The experiment was conducted in a greenhouse, where RB867515 and RB855453 varieties were evaluated, by water stress or not water stress, in relation to SPAD index, total chlorophyll content, leaf temperature, leaf water potential (ψw), CO2 rate assimilation, maximum quantum efficiency of photosystem II (Fv/Fm), photosynthetic active radiation, temperature and humidity on +1 leaf in four times of the day (7, 10, 13 and 16 hours). Thus, we found the variation of SPAD index during the day, that showed a decreasing tendency over the hours, and it was verified that the total chlorophyll content extracted ranging in the same way. Overall, the most significant results of physiological parameters, except for stomatal conductance, for the maximum quantum efficiency of photosystem II (Fv/Fm) and for the water use efficiency ...

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37

Oliveira, Tiago Filipe Martins de. "Evolução ao longo do tempo de vida útil do teor microbiológico de queijos frescos mantidos sob refrigeração doméstica." Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2010. http://hdl.handle.net/10400.5/2266.

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Dissertação de Mestrado Integrado em Medicina Veterinária
Os conceitos de qualidade e segurança alimentar, assim como os hábitos de vida dos consumidores têm evoluído ao longo dos tempos. Os consumidores estão cada vez mais adeptos das grandes superfícies comerciais, aumentando desta forma o negócio na área da distribuição. As empresas de distribuição, com o aumento da competitividade do sector, tentam melhorar os seus serviços para responder às exigências dos clientes, nomeadamente pela criação de equipas de gestão de reclamações de cliente para a resolução mais rápida e eficiente dos problemas. O queijo, alimento muito famoso em todo o mundo, com algumas regiões demarcadas, com impacto real na economia dos diversos países, é um dos produtos que não escapa a esta crescente onda de exigência. As imposições reflectem-se também na área da saúde, tendo os queijos frescos, visto o seu consumo aumentado. Pelas etapas inerentes ao seu processo de fabrico, o queijo fresco é um alimento muito perecível, sendo alvo de diversas reclamações. Alguns tipos de reclamações, em relação a este produto, motivaram a realização deste estudo, que consistiu na avaliação microbiológica de queijos frescos de leite de vaca, ovelha e cabra, durante o seu tempo de vida útil, armazenados em refrigeração doméstica. Por outro lado, paralelamente, tentou-se estabelecer uma comparação entre queijos frescos de fabrico industrial e artesanal. Conclui-se que nos queijos estudados deveriam ser melhoradas as condições de higiene de produção, principalmente nos de leite de cabra. No entanto revelou-se na evolução das contagens de microrganismo, nos queijos armazenados em refrigeração doméstica, que a principal falha, se encontra na manutenção a temperaturas de refrigeração inadequadas. Quanto à comparação artesanal com industrial, para os queijos estudados, não se encontraram grandes diferenças no teor microbiológico.
ABSTRACT - Evolution of microbiological levels throughout the shelf-life of fresh cheese kept under domestic refrigeration - The concepts of food quality and safety, as well as consumer habits, have evolved over the years. The major surfaces are gaining more and more supporters, providing a huge boost to the distribution business. Distribution companies try to expand in order to meet client demands and maintain a certain level of healthy competition within the sector. One of the breakthroughs was the creation of Customer Support Teams that provide a fast and efficient problem resolution service. Cheese is one of the foods most appreciated all over the world - including several Demarcated Regions that affect their respective country’s economy - and does not escape to these increased demands. These requirements also have an impact on the Health sector, since products such as fresh cheese have suffered a major consumption increase in the last few years. The several stages of fresh cheese production make it a highly perishable food product, witch could result in several complaints from the consumers. Some of the complaints regarding this product led to this case study, witch consisted in the microbiological evaluation of domestically refrigerated fresh cheese made from cow, sheep and goat milk, throughout their shelf-life. At the same time this study also tried to establish a comparison between industrial and homemade cheese. With the results obtain in this study it is possible to conclude that there should be an improvement in the hygiene conditions at the production stage, mostly regarding goat cheese. However, the bacteria count evolution noted that in the domestically refrigerated fresh cheese the main flaw is the break of the cooling chain, due to the difficulty of maintaining the appropriate temperatures. As for the industrial / homemade comparison, this study did not find any significant differences in the analyzed items.

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Gérard, Yannick. "Mémoire sémantique et sons de l'environnement." Dijon, 2004. http://www.theses.fr/2004DIJOL011.

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Vous vous promenez tranquillement, au loin vous entendez un chien aboyer. Un chien ? Mais comment savez-vous qu'il s'agit d'un un chien ? Par ailleurs, l'aboiement de ce chien vous prépare-t-il à entendre d'autres sons ? Voici posés les deux objectifs centraux de cette thèse, déterminer si un son active une structure de connaissances abstraites en mémoire sémantique, et si oui, comment ces structures s'organisent-elles ? Dix expériences reparties en 3 études tentent de répondrent à ces deux objectifs. Une première étude de 4 expériences d'amorçage à court terme en contexte court indique que les sons de l'environnement activent des structures de connaissances abstraites en mémoire sémantique. Les résultats suggèrent des dissemblances entre l'organisation des mots et des sons de l'environnement. Les liens qui unissent les sons de l'environnement en mémoire sont étudiés au travers d'une expérience d'association libre, de deux expériences de catégorisation libre et d'une en amorçage à court terme (Étude 2), qui mettent en évidence que de nombreux facteurs influencent le traitement des sons de l'environnement (médiation langagière, " stress " temporel, appartenance catégorielle des sons, incertitude quant à la cause du son). Les sons de l'environnement semblent s'organiser en fonction d'une part, du lieu où nous pouvons les entendre ensemble (ferme, rue, etc. . . ) et d'autre part, de certaines caractéristiques acoustiques. Dans une troisième et dernière étude d'amorçage à court terme en long contexte (phrases et scènes sonores) un maximum de ces facteurs est contrôlé et l'organisation des sons observée dans la deuxième étude est prise en compte. Les résultats sont asymétriques et montrent qu'une phrase facilite le traitement d'un son congru comparé au traitement d'un son incongru, l'inverse est observé quand le contexte correspond à une scène auditive " naturelle ". Les résultats de notre étude en contexte " naturel " sont interprétés avec le phénomène du " pop out ". Ce travail de thèse suggère que les sons de l'environnement activent des connaissances conceptuelles dans la mémoire sémantique dévolue au langage et s'organisent en MLT sous forme de scènes auditives dépendantes du lieu où nous sommes en train d'évoluer (gare, rue, ferme, etc. . . ) qui ne créent pas d'attentes pour tous les objets sonores probables dans cette scène et rendent plus saillants tous les sons inattendus dans cette même scène sonore
You're walking quietly and far away you hear a barking dog. A dog? But how do you know that it is a dog? In addition, does this barking dog prepare you it to hear other sounds? Here are the two central purposes of this thesis, determine if a sound activates an abstract structure of knowledge in semantic memory, and if so, how these structures were organised? Ten experiments organised in 3 studies investigate these questions. A first study of 4 experiments in short-term priming with short context indicates that environmental sounds activate abstract structures of knowledge in semantic memory. The results suggest dissimilarities between the organisation of words and the organisation of environmental sounds in LTM. The way environmental sounds are linked (to each other) in memory are studied with a free association experiment, two experiments of free categorization and a short-term priming experiment (Study 2). They highlight that many factors influence the processing of these sounds (linguistic mediation, temporal "stress", sound categories, uncertainty about the cause of the sound). The environmental sounds seem organise as a function of the place where we can be heard together (farm, street, etc. . . ) and certain acoustic characteristics. In a third and last study of short-term priming with long context (sound sentences and auditory scenes) a maximum of these factors is controlled and the organisation of sounds observed in the second study is taken into account. The results are asymmetrical and show that a sentence facilitates the processing of congruent sounds compared with incongruent sounds, the reverse is observed when the context is a naturalistic auditory scene. The results of our study in naturalistic context are interpreted with the "pop out" phenomenon. This thesis suggests that environmental sounds activate conceptual knowledge in semantic memory used for the language and are organised in LTM in auditive scenes which do not create any expectancies about the probable sound objects in this scene and make more obvious all the unexpected sounds in this same scene

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龍潤華. "陳子龍與幾社研究 = The research of Chan Chi-Long and Ji She." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1636966.

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Paiva, Getúlio Eduardo Rodrigues de. "Estudo de esquemas de amplificação para redes PON de longo alcance." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-07052012-095117/.

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O surgimento de novos serviços que requerem uma largura de banda cada vez maior, bem como o crescente número de usuários de tais serviços, têm introduzido desafios às empresas operadoras de telecomunicações em sua capacidade de atender a estas demandas sem perda apreciável da qualidade de serviço e mantendo, ainda assim, os custos num nível aceitável pelos usuários. Neste contexto, redes ópticas passivas (PONs) vêm atraindo grande interesse em anos recentes. Na sua variante de longo-alcance, as redes PON permitem uma consolidação do uso dos equipamentos e centrais de serviço requeridos, reduzindo custos operacionais e de instalação. Uma das formas de atingir este maior alcance dá-se por meio da inserção de amplificadores ópticos nas redes de acesso. Neste trabalho, portanto, estudaram-se alguns tipos de amplificadores ópticos e suas possíveis aplicações em redes de acesso, levando a topologias de longo alcance e alta capacidade. Foram realizadas avaliações experimentais de um extensor, baseado em amplificadores ópticos semicondutores (SOAs), na rede GPON do CPqD, sob a Meta 3 do Projeto GIGA, possibilitando a obtenção de uma topologia do tipo Fiber-to-the-Building (FTTB) com 80 km de extensão e 128 usuários atendidos por uma única central de serviço. Além dessas validações experimentais, foram simulados computacionalmente SOAs com características otimizadas bem como sistemas que utilizam fibras dopadas com érbio bombeadas remotamente, sendo que nestes últimos, atingiram-se distâncias superiores a 100 km.
The emergence of new services which require an increasing bandwidth, as well as the growing number of users of such services, have introduced challenges to the network operators in regard to their capacity of supporting these demands with no penalty on the required quality of service, while keeping the costs at an acceptable level for the users. In this context, passive optical networks (PONs) have attracted a great deal of interest in recent years. In the long-reach configuration, PON networks allow for a consolidation of equipament usage, reducing operational and installation costs. One way to achieve this longer reach is by the insertion of optical amplifiers in the access network. Therefore, in our work, we have investigated several optical amplifier configurations, as well as their application in access networks, leading to longreach and high capacity network topologies. Experimental evaluations of an extender, based on semiconductor optical amplifiers, were carried out in the CPqD GPON network, under Goal 3 of GIGA Project, allowing the achievement of a Fiber-to-the-Building (FTTB) topology with 80km of extension and 128 users served by a single central office. Besides these experimental validations, were simulated computationally SOAs with optimized characteristics as well as systems using remotely pumped erbium-doped fibers, whereas in the latter were reached distances exceeding 100 km.

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Gonçalves, Daniel Ruiz Potma. "ESPACIALIZAÇÃO DO CARBONO E SUAS RELAÇÕES COM A PRODUTIVIDADE DE CULTURAS EM SOLOS SOB PLANTIO DIRETO DE LONGA DURAÇÃO." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2014. http://tede2.uepg.br/jspui/handle/prefix/2255.

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Made available in DSpace on 2017-07-25T19:30:46Z (GMT). No. of bitstreams: 1 Daniel Potma.pdf: 2269780 bytes, checksum: 5e498b4886f52a509f48ad0c44a512b3 (MD5) Previous issue date: 2014-07-23
The total organic C (TOC) of the soil influences their chemical, physical and biological properties, therefore, it's important for the maintenance of soil fertility mainly of tropical soils. But, while the benefits of TOC accumulation on soil quality are well known, there is still little information about its effects on crop yields. The aims of this work were to map the compartments of the TOC on a farm managed for 30 years in no-till system, determine which soil variables that influence the spatial variation of TOC and analyze the relationships between the compartments of TOC and crop yields of soybean, corn and wheat. Deformed samples were collected in all soil classes and all landscape positions in the farm. Were analyzed the TOC, the permanganate oxidized C (POX-C) and the hot water extracted C (HWE-C) and were generated maps with the spatial variation of these variables. The effects of soil properties on the accumulation of TOC and the effect of TOC compartments on yields of soybean, corn and wheat were accessed through regressions and principal component analysis. Aiming to access the contribution of TOC to the crop yields, multiple regressions with the soil variables and yields were adjusted. The higher clay content and the largest biomass apport in Oxisols and the formation of an anaerobic environment in Inceptisols were the main factors that explained the highest contents of TOC observed in the upper thirds of the Oxisols and lower thirds of the Inceptisols. Yields of wheat and soybean showed positive correlation with TOC and total N (TN) and corn yield was positively correlated with HWE-C. The TN and TOC were the variables that contributed most to explain the variations in the wheat yield.
O C orgânico total (COT) do solo exerce influência sobre suas propriedades químicas, físicas e biológicas, sendo assim, importante para a manutenção da fertilidade principalmente de solos tropicais. Porém, embora os benefícios do acúmulo de COT sobre a qualidade do solo sejam bem conhecidos, ainda são escassas informações referentes aos seus efeitos sobre a produtividade de culturas. Os objetivos deste estudo foram mapear os compartimentos de COT em uma fazenda manejada há 30 anos no sistema plantio direto, verificar quais são as variáveis do solo que interferem na variação espacial do COT e analisar as relações entre os compartimentos do COT e a produtividade das culturas da soja, milho e trigo. Foram coletadas amostras deformadas em todas as principais classes de solos da fazenda em todas as posições da paisagem. Foram analisados o COT, o C oxidado por permanganato (C-OXP) e o C extraído por água quente (C-EAQ) e gerados mapas com a variação espacial destas variáveis. Os efeitos dos atributos do solo sobre o acúmulo de COT e dos compartimentos de COT sobre as produtividades da soja, milho e trigo foram acessados através de regressões e análises de componentes principais. Visando acessar a contribuição do COT para as produtividades das culturas foram ajustadas regressões múltiplas com as variáveis do solo e as produtividades. O maior conteúdo de argila e a maior adição de fitomassa nos Latossolos e a formação de um ambiente anaeróbico nos Cambissolos foram os principais fatores que explicaram os maiores conteúdos de COT observados nos terços superior dos Latossolos e inferior dos Cambissolos. As produtividades de trigo e soja apresentaram correlação positiva com o COT e o N total (NT) e a produtividade de milho apresentou correlação positiva com o C-EAQ. As variáveis NT e COT foram as que mais contribuíram para explicar a variação da produtividade de trigo.

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TREVISAN, E. "Microclima sob a copa do mamoeiro cultivado com café e em diferentes orientações de plantio, ao longo do ano." Universidade Federal do Espírito Santo, 2017. http://repositorio.ufes.br/handle/10/8223.

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Made available in DSpace on 2018-08-01T23:26:41Z (GMT). No. of bitstreams: 1 tese_11255_Dissertação - Evelyn Trevisan.pdf: 1360083 bytes, checksum: d0a47305c56a36192a62285de70a9c71 (MD5) Previous issue date: 2017-07-28
O café Conilon é uma espécie originalmente adaptada a ambientes parcialmente sombreados, entretanto, no Brasil, seu cultivo é realizado a pleno sol. Durante a fase crítica de enchimento dos grãos, o cafeeiro frequentemente é submetido a temperaturas elevadas, o que pode causar estresse à cultura, exigindo diferentes técnicas para mitigar esses problemas. Dessa forma, o sombreamento surge como uma técnica para mitigação de variáveis climáticas. Neste contexto, desenvolveram-se dois trabalhos: o primeiro objetivou-se avaliar o microclima e o desenvolvimento do cafeeiro Conilon, em um sistema de cultivo de café consorciado com mamoeiro. O mamoeiro foi plantado no espaçamento de 3,20x2,40m, em julho de 2014, já o café, foi implantado no espaçamento de 3,20x1,60m, em março de 2015, na linha do mamoeiro. Considerou-se como tratamentos as distâncias da linha do cafeeiro e mamoeiro (40 e 80cm norte e sul) e a pleno sol, na orientação norte e sul. Avaliou-se as variáveis atmosféricas (temperatura, irradiância, umidade relativa), área foliar e índice relativo de clorofila, comprimento dos ramos plagiotrópicos, ortotrópicos e número de nós, em três épocas do ano. O consórcio do cafeeiro Conilon com Mamoeiro proporcionou diminuição da irradiância e da temperatura, e valores superiores de umidade relativa do ar durante o dia em todas as épocas avaliadas. O sombreamento proporcionou maior expansão foliar, entretanto não influenciou no crescimento de ramos plagiotrópicos e ortotrópicos e no número de nós. O sistema de consórcio do cafeeiro Conilon com mamoeiro nas condições estudadas apresentou potencial. O segundo teve como objetivo avaliar as variações dos fatores ambientais sob a copa do mamoeiro, plantado no sentido de orientação Norte-Sul e Leste-Oeste. Foram utilizadas duas áreas de mamão, uma plantada na orientação Norte-Sul e outra Leste-Oeste, implantadas no espaçamento 3,20x2,40m, ambas plantadas em abril de 2015. Considerou-se como tratamentos as distâncias da linha do mamoeiro, e um local a pleno sol, onde avaliou-se, no sentido Norte-Sul: na linha de plantio do mamão (T1), à 40cm lado oeste (T2 O), 40cm lado leste (T3 L) e a pleno sol (T4 Sol); no sentido Leste-Oeste: na linha de plantio do mamão (T1), à 40cm lado norte (T2 N), 40cm lado Sul (T3 S) e na linha de plantio a pleno sol (T4 Sol). Avaliou-se as variáveis atmosféricas (temperatura, irradiância, humidade relativa). O mamoeiro plantado no sentido Leste-Oeste, nas condições estudadas, proporcionou menor irradiação incidente, redução na temperatura e valores superiores de umidade relativa do ar sob sua copa. De acordo com as condições microclimática apresentadas, torna-se possível o consórcio do mamoeiro plantado nos dois sentidos.

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Reynes, Jérôme. "Procédé de confinement d'éléments radioactifs à vie longue par frittage d'une matrice poreuse de silice." Montpellier 2, 1998. http://www.theses.fr/1998MON20143.

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Le confinement des dechets radioactifs en france s'effectue actuellement par leur incorporation dans un verre borosilicate de type eau legere. De nouvelles matrices de confinement sont envisagees, specifiques a quelques radioelements a vie longue et devant presenter une meilleure durabilite chimique. Le procede mis en place dans ce travail consiste en l'enrobage de simulants d'actinides (neodyme et cerium) dans une matrice de silice vitreuse. Celle-ci constitue un tres bon candidat pour les criteres de surete du confinement et notamment pour la resistance a l'attaque chimique de l'eau, principal vecteur de corrosion des materiaux de confinement a long terme. Il s'agit d'integrer les elements a confiner dans un materiau poreux de silice, synthetise par voie sol gel, par des etapes d'impregnation et de sechage avec des solutions contenant ces elements. Par la suite, la matrice poreuse est densifiee par un traitement thermique de frittage vers 1100 a 1200c, piegeant ainsi les simulants. Les proprietes mecaniques et texturales de ce materiau poreux ont ete caracterisees. Une methode originale, selon le principe de poussee d'archimede, a ete mise en place pour etudier l'impregnation, la permeabilite et les phenomenes de diffusion dans le reseau poreux. Les materiaux de confinement vitrocristallins finalement realises, silice-cerium et silice-neodyme, ont ete caracterises sur le plan structural (rx et meb), mecanique et de la durabilite chimique. Leur caracterisation montre des differences nettes qui sont correlees avec la difference d'affinite de nd(iii) et ce(iv) avec la silice. Ceci a mis en evidence l'importance du critere de segregation entre matrice de silice et elements a confiner pour valider ce procede. Ainsi, dans le cas du materiau silice-cerium, la vitesse de dissolution mesuree (test soxhlet) est environ 60 fois inferieure a celle du verre borosilicate de confinement.

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Larby, Line. "Development of Novel (Cu,Fe)3O4 Coatings for AISI 441 Solid Oxide Cell Interconnects : Coating optimization and long-term study." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279130.

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As current environmental challenges are gaining increased attention, development of clean energy solutions is becoming one of the essential strategies to keep within the boundaries of established environmental policies. Solid oxide cell (SOC) technology can provide clean energy conversion and storage when hydrogen is the energy carrier. The high total energy conversion efficiency resulting from the high operation temperature of SOCs make the technology promising, but material costs must be reduced to make it commercially viable. Therefore, this thesis aims to study the long- term performance of a novel cost-optimized cell interconnect at 650 and 850 °C. At high temperatures, chromium evaporation from the interconnect result in electrode poisoning, which may be mitigated by application of a protective coating. The studied interconnect is an AISI 441 steel with some different pre-oxidized copper and iron spinel coatings. Sample analysis was made mainly with scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and X-ray diffraction. It was found that the most promising pre-oxidation treatment was 24 h at 750 °C and that chromium migration was restrained at 650 °C long-term treatment but not at 850 °C where it wasfound available for evaporation at the surface.
När samtida milljöutmaningar får ökad uppmärksamhet blir gröna energilösningar en av de viktigaste strategierna för att hålla sig inom satta gränser från etablerade miljöriktlinjer. Teknologin bakom fastoxidceller, eller solid oxide cells (SOCs), kan bidra med grön omvandling och lagring av energi när energibäraren är väte. Den höga totala omvandlingseffektiviteten, som kommer med den höga verkningstemperaturen, gör SOC till en lovande teknologi, men materialkostnaderna måste först reduceras innan den blir komersiellt gångbar. Därför syftar detta examensarbete till att undersöka prestandan av en ny, kostnadsoptimerad cellinterkonnektor på lång sikt i 650 och 850 °C. Vid höga temperaturer förångas krom från interkonnektorn, vilket leder till elektrodförgiftning, men kan mildras genom applicering av en skyddande beläggning. Den undersökta interkonnektorn är ett stål som betäcknas AISI 441 belagt med några olika föroxiderade beläggningar av koppar- och järnspinell. Proverna analyserades i huvudsak genom svepelektronmikroskopi kobinerat med energidispersiv röntgenspektroskopi och röntgendiffraktometri. Det visades att den mest lovande föroxideringsbehandlingen var 24 h i 750 °C och att krom förblev återhållet vid 650 °men inte vid 850 °C då det fanns tillgängligt för förångning vidytan.

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Neto, Waldemiro de Aquino Pereira. "Análise de fatores intervenientes nas características dimensionais de segmentos rodoviários sob a óptica da compatibilidade veículo-via." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-15102007-104749/.

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O setor rodoviário no Brasil é o maior responsável pelo transporte de passageiros e de cargas. A indústria de veículos de carga tem realizado modificações nas características dos veículos e a tendência neste mercado é o aumento na capacidade de transporte, obtida com a fabricação de veículos com maiores dimensões, com um maior número de eixos, bem como a utilização de combinações de veículos de carga (CVCs). Estas alterações atendem uma exigência do mercado, que é o aumento da produtividade nos serviços de transporte. Para uma operação segura, entretanto, se faz necessário garantir a compatibilidade entre os veículos e a malha rodoviária ofertada para absorver este tráfego. O objetivo principal deste trabalho é investigar as características e padrões dos veículos que trafegam nas rodovias brasileiras, visando à proposição de parâmetros de projeto geométrico compatíveis, contemplando os aspectos da interação dos veículos e da via, com ênfase para os veículos de grande porte, e em particular os veículos do tipo CVC. São propostos ajustes nos padrões técnicos estabelecidos pelo DNER, atual DNIT, de forma a adequar a geometria das rodovias às características e restrições dos veículos em operação. Foi realizado ainda um estudo de caso para um conjunto de trechos de rodovias no Estado de São Paulo e no Estado do Ceará, com características técnicas diferentes, onde trafegam CVCs de diversas configurações com restrições, permitindo que sejam identificados os ajustes necessários na geometria para adequação ao tráfego, bem como orientar a concepção de outros projetos.
In Brazil the majority of passenger and goods transportation is carried out by the highway transportation system. Vehicle industry does a continuous job of designing new models in order to increase capacities, producing bigger vehicles, with more axles, as well as long combination vehicles (LCVs). These modifications aim to attend a market demand that is looking for better productivity figures for transportations services. However, to assure a good level of safety in the operation of these vehicles, it is necessary a guarantee of compatibility of them with the roads where they will circulate. The main objective of this thesis is the research of the characteristics and standards of vehicles traveling on brazilian roads, in order to analyze design parameters, considering the interaction between vehicles and roads. The problem of the flow of large vehicles, in particular LCVs, is emphasized. Adjustments on the design standards, established by the DNER (presently named DNIT), are proposed with the intention of adequate the road geometry to the vehicles characteristics and restrictions. A case study was carried out for a set of highway segments of the states of São Paulo and Ceará. These segments present different technical characteristics and are traversed, with some restrictions, by different types of LCVs. This study allows not only the identification of necessary adjustment on the road geometry to hold up the existing traffic flow, but also the design of new projects standards.

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Melo, Cristina. "Determinantes da estrutura de capitais das PME's em Portugal: a relevância do sector de actividade." Master's thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/14698.

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Neste trabalho procuramos encontrar os determinantes da estrutura de capitais das PME’s em Portugal, através do estudo de hipóteses já testadas em estudos anteriores, em especial no que se refere à importância do sector de actividade1 como determinante dessa estrutura. Um aspecto particular que se pretende captar é a questão do crescimento e investimento que, frequentemente, aparece associado à inovação tecnológica. Procura-se também analisar se a teoria existente sobre estrutura de capitais, desenvolvida com base nas grandes empresas, se aplica à realidade das PME’s portuguesas. Deste modo, utilizando dados em painel, para o período entre 2006 e 2008, é analisada uma amostra das PME’s portuguesas, dados agregados por sector, de modo a poder confirmar, ou não, os resultados de estudos anteriores. Os resultados indicam que o sector de actividade é um determinante da estrutura de capitais das PME’s. Foi verificada uma relação positiva do endividamento de curto prazo com o crescimento e com a inovação e do endividamento de médio e longo prazo com a proporção de activos fixos e com a dimensão. Por sua vez o endividamento de curto prazo apresentou uma relação negativa com a proporção de activos fixos e a dimensão enquanto no caso do endividamento de médio e longo prazo a relação negativa foi verificada com a rendibilidade e o risco; ABSTRACT: In this work we try to identify the determinants of the capital structure of the SME’s in Portugal, by studying hypotheses tested in previous studies, especially in what concerns the importance of the sector of economic activity as a determinant of the capital structure. One particular aspect that we want to capture is the question of growth and investment that often seems to be associated with technological innovation. We also try to establish if the existing theory on capital structure, which was developed based on large enterprises, is applicable to the case of Portuguese SME’s. Using panel data for the period from 2006 to 2008, a sample of Portuguese SME´s is analyzed using aggregate data by sectors of economic activity, in order to verify if the results of previous studies can be confirmed or not. The results indicate that the sector of economic activity is a determinant factor in the capital structure of Portuguese SME’s. A positive relationship was verified between short term debt and growth and innovation and between medium and long term debt with the proportion of fixed assets and size. Short term debt has a negative relationship with the proportion of fixed assets and size, while medium and short term debt has a negative relationship with risk and profitability.

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47

Sandor, Leonardo Taborda. "Uma metodologia para a avaliação dos gradientes de tenacidade a fratura ao longo da camada cementada do aço SAE 5115." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264971.

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Orientador: Itamar Ferreira
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-04T09:29:09Z (GMT). No. of bitstreams: 1 Sandor_LeonardoTaborda_M.pdf: 9634671 bytes, checksum: 3b7603db85e265d8bd0e3fc244928942 (MD5) Previous issue date: 2005
Resumo: Este trabalho propõe um modelo para avaliar pontualmente as variações de tenacidade à fratura ao longo da camada cementada de um aço SAE 5115. A pequena espessura dessas camadas impede a retirada de corpos de prova nas dimensões especificadas pelas normas de ensaios de tenacidade à fratura. Assim, para simular uma camada cementada retirou-se corpos de prova de tração e de tenacidade à fratura de amostras de aços SAE 5115, 5140, 5160 e 52100 assumindo a influência local apenas da variação do teor de carbono e considerando que os teores dos demais elementos de liga são essencialmente constantes. Os corpos de prova após eletrodeposição de cobre foram tratados termicamente numa carga industrial de cementação, têmpera e revenimento para serem submetidos aos efeitos térmicos sem absorção de carbono. Os resultados da análise microestrutural, dos ensaios de microdureza, de tração e de tenacidade à fratura foram agrupados em um único gráfico e comparados com o perfil de cementação de peças de aço SAE 5115 tratadas nas mesmas condições. Foi confirmado que a tenacidade à fratura varia inversamente proporcional à microdureza (HV1) e que a previsão do comportamento de uma trinca numa camada cementada pode ser feita por meio de equação ou diagrama que relacionam a miicrodureza HV1 com a tenacidade à fratura (K1c ou CTODc)
Abstract: The purpose of this work is to propose a model for evaluating the fracture toughness along the SAE 5115 steel carburized layer. Due to the small thickness of those layers, it is impossible to machine specimens from those layer in accordance with standards. For simulating the microstructures of the carburized layer in order to get samples for tensile and the fracture toughness testing, specimens of SAE 5115, 5140, 5160, and 52100 steels assuming the local influence just of the variation of the content of carbon and considering that the contents of the other alloy elements are essentially constant. The specimens after electroplated copper layer were heat treated in an industrialload of carburizing, quenching, and tempering for they be submitted to the thermal effects without absorption of carbono The results of the microstructure analysis and microhardness, tension, and fracture toughness tests were placed in a single graph and compared with the profile of the carburizing of the steel SAE 5115 heat treated in the same conditions. It was confirmed that the fracture toughness varies inversely proportional to the microhardness (HV1) and that the forecast of the behavior of a crack in a carburized layer can be made through equation or it designs that relate the microhardness (HV1) with the fracture toughness (KIC or CTODc)
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica

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48

Bakker, Eleanor. "The impact of plant growth and potassium uptake on clay minerals in soil." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAU012/document.

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Le potassium est un nutriment essentiel à la croissance et au développement des plantes. Les minéraux argileux dans les sols représentent un important réservoir de K disponible pour les plantes. L'extraction de K fixé à partir de l'espace interfoliaire des minéraux micacés 2:1 peut entraîner une augmentation de la distance feuillet à feuillet qui peut être mesurée par diffraction des rayons X . Des échantillons de l'expérience Morrow Plots continue avec du maïs (C) ou du maïs-avoine-foin (R), provenant de sous-parcelles fertilisées (F) et non fertilisées (U) pour les années 1904, 1957, 1980, 1997 et 2013-2014, ont été soumis au fractionnement granulométrique séquentiel pour obtenir la fraction limoneuse (50-2 um) et les sous-fractions argileuses (2-0,2, 0,2-0,05 et <0,05 um). Les résultats granulométriques montrent une hétérogénéité significative malgré la petite taille de la MP, et un gain de sous-fraction < 0,05 um avec le temps. La modélisation des diagrammes de diffraction des rayons X a été effectuée pour obtenir une identification concluante de l'assemblage de minéraux argileux et évaluer l'impact de 110 ans d'agriculture continue et de différentes pratiques agronomiques. Un assemblage complexe de minéraux argileux a été identifié avec jusqu'à onze contributions différentes nécessaires pour reproduire les données expérimentales de sous-fractions de moins de 2 um, y compris jusqu'à six couches mixtes d'illite-smectite-chlorite. L'analyse de phase quantitative pour toutes les sous-parcelles et toutes les années, a montré que l'assemblage minéral du MP est similaire entre les différentes sous-parcelles, quel que soit le traitement agronomique. Aucune preuve significative d'altération ou de transformation des phases minérales argileuses n'a été observée au fil du temps. La nature dioctaédrique des minéraux argileux de la MP désavantage l'extraction du K et donc la dissolution est le mécanisme privilégié pour l'absorption du K et la perte de sous-fractions 2-0,2 et 0,2-0,05 um est attribuée à ce processus
Potassium is an essential nutrient for plant growth and development. Clay minerals in soils represent an important reservoir of plant-available K. Extraction of fixed K from the interlayer space of micaceous 2:1 minerals can lead to an increase in the layer-to-layer distance which can be measured by X-ray diffraction. Samples from the Morrow Plots continuous corn (C) and corn-oats-hay (R) experiment, from fertilised (F) and non-fertilised (U) subplots for the years 1904, 1957, 1980, 1997 and 2013-2014 were subjected to sequential size-fractionation to obtain the silt fraction (50-2 um) and clay-sized subfractions (2-0.2, 0.2-0,05 and <0.05 um). Granulometric results show siginificant heterogeneity despite the small size of the MP, and a gain in <0.05 um subfraction with time. Full-profile fitting of X-ray diffraction patterns was performed to obtain conclusive identification of the clay mineral assemblage and assess the impact of 110-years of continuous agriculture and different agronomic practices. A complex clay mineral assemblage was identified with up to eleven different contributions necessary to reproduce the experimental data of <2 um subfractions, including up to six illite-smectite-chlorite mixed-layers. Quantitative phase analysis for all subplots and years showed that the mineral assemblage of the MP is similar between different subplots, regardless of agronomic treatment. No significant evidence of alteration or transformation of clay mineral phases was observed over time. The dioctahedral nature of the clay minerals of the MP disfavours K-extraction and thus dissolution is the favoured mechanism for K-uptake and the loss of 2-0.2 and 0.2-0.05 um subfractions is attributed to this process

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49

Georgii, Linnea. "How Do Long-Term Declines in Anthropogenic Sulfur Dioxide Emissions and Sulfate Wet Deposition Compare with Trends in Freshwater Chemistry in Scandinavian Rivers?" Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326709.

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Acidification of precipitation is an important environmental problem that emerged during the past century, especially after the Second World War. Acidification was primarily caused by human-made emissions of SOx (mostly SO2) and NOx, which are oxidized sulfur and nitrogen gases. The main sources of anthropogenic SOx emissions are non-ferrous ore refining, and the burning of fossil fuels and biofuels. SO2 emitted to the atmosphere combines with water vapor to produce sulfuric acid, which is one of the main compounds responsible for acid precipitation. In the 1970s and 1980s, more strict regulations regarding emissions of air pollutants such as SOx were established in Western Europe and North America, which led to declining levels of SO2 emissions and by this, declining levels of acidification in surface waters. This project was preformed by assembling and analyzing existing, publicly- available datasets of anthropogenic SO2 emissions for the period 1970 to 2010 from ten different regions in the Northern Hemisphere, and compare them with SO42- concentrations in precipitation and river chemistry in Sweden and Norway for the same period. It was discovered that it is the SO2 emissions from Northwestern Europe, the UK & Ireland and from the USA that have the greatest influence over the SO42- concentration in Scandinavian rivers. The SO42- concentration in stream water is also declining faster than the concentration in precipitation, with a faster decline in the southern parts of Scandinavia.
Försurning av nederbörd är ett miljöproblem som uppstod under det senaste århundradet, särskilt efter andra världskriget. Försurningen orsakades främst av mänskliga utsläpp av SOx (mestadels SO2) och NOx, vilka är oxiderade svavel- och kvävgaser. Huvudkällorna för dessa antropogena SOx-utsläpp är malmförädling samt förbränning av fossila bränslen och biobränslen. SO2 som släpps ut i atmosfären reagerar med vattenånga och bildar svavelsyra, vilket är en av huvudföreningarna ansvarig för sur nederbörd. På 1970- och 1980-talet fastställdes strängare bestämmelser beträffande utsläpp av luftföroreningar (som SOx) i Västra Europa och i Nordamerika. Detta ledde till minskande nivåer av SO2-utsläpp och genom denna sänkning även en minskning av försurning av ytvatten. Det här arbetet utfördes genom att befintlig, offentligt tillgänglig data samlades in och analyserades. Antropogena SO2-utsläpp för perioden 1970-2010 från tio olika regioner på norra halvklotet jämfördes med koncentrationer av SO42- i nederbörd och i vattendrag i Sverige och Norge för samma period. Genom detta fastslogs att de regioner som har störst inflytande över koncentrationen i skandinaviska vattendrag är SO2-utsläpp från nordvästra Europa, Storbritannien och Irland samt från USA. SO42- koncentrationen i vattendragen sjunker också snabbare än koncentrationen i nederbörden, med en snabbare nedgång i de södra delarna av Skandinavien.

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50

Oliveira, Alexandre de. "Controle ótimo de sistemas lineares com saltos Markovianos e ruídos multiplicativos sob o critério de média variância ao longo do tempo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3139/tde-16042012-101655/.

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Este estudo considera o modelo de controle ótimo estocástico sob um critério de média-variância para sistemas lineares a tempo discreto sujeitos a saltos Markovianos e ruídos multiplicativos sob dois critérios. Inicialmente, consideramos como critério de desempenho a minimização multiperíodo de uma combinação entre a média e a variância da saída do sistema sem restrições. Em seguida, consideramos o critério de minimização multiperíodo da variância da saída do sistema ao longo do tempo com restrições sobre o valor esperado mínimo. Condições necessárias e suficientes explícitas para a existência de um controle ótimo são determinadas generalizando resultados anteriores existentes na literatura. O controle ótimo é escrito como uma realimentação de estado adicionado de um termo constante. Esta solução é obtida através de um conjunto de equações generalizadas a diferenças de Riccati interconectadas com um conjunto de equações lineares recursivas. Como aplicação, apresentamos alguns exemplos numéricos práticos para um problema de seleção de portfólio multiperíodo com mudança de regime, incluindo uma estratégia de ALM (Asset and Liability Management). Neste problema, deseja-se obter a melhor alocação de portfólio de forma a otimizar seu desempenho entre risco e retorno em cada passo de tempo até o nal do horizonte de investimento e sob um dos dois critérios citados acima.
In this work we consider the stochastic optimal control problem of discrete-time linear systems subject to Markov jumps and multiplicative noise under two criterions. First, we consider an unconstrained multiperiod mean-variance trade-off performance criterion. In the sequence, we consider a multiperiod minimum variance criterion subject to constraints on the minimum expected output along the time. We present explicit necessary and sufficient conditions for the existence of an optimal control strategy for the problems, generalizing previous results in the literature. The optimal control law is written as a state feedback added with a deterministic sequence. This solution is derived from a set of coupled generalized Riccati difference equations interconnected with a set of coupled linear recursive equations. As an application, we present some practical numerical examples on a multiperiod portfolio selection problem with regime switching, including an Asset and Liability Management strategy. In this problem it is desired to nd the best portfolio allocation in order to optimize its risk-return performance in every time step along the investment horizon, under one of the two criterions stated above.In this work we consider the stochastic optimal control problem of discrete-time linear systems subject to Markov jumps and multiplicative noise under two criterions. First, we consider an unconstrained multiperiod mean-variance trade-off performance criterion. In the sequence, we consider a multiperiod minimum variance criterion subject to constraints on the minimum expected output along the time. We present explicit necessary and sufficient conditions for the existence of an optimal control strategy for the problems, generalizing previous results in the literature. The optimal control law is written as a state feedback added with a deterministic sequence. This solution is derived from a set of coupled generalized Riccati difference equations interconnected with a set of coupled linear recursive equations. As an application, we present some practical numerical examples on a multiperiod portfolio selection problem with regime switching, including an Asset and Liability Management strategy. In this problem it is desired to nd the best portfolio allocation in order to optimize its risk-return performance in every time step along the investment horizon, under one of the two criterions stated above.

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Dissertations / Theses on the topic 'Soe longe'

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