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Nilsen, Geir Werner. "Topics in open and closed loop subspace system identification : finite data-based methods." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1752.
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Demirdögen, İbrahim. "Comparison and Improvement of Different Access Methods in Femtocell Networks." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1612.
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A variety of wide band wireless systems have been pushed towards their limits in order to meet growing interest for high data rate in wireless communications.In particular, the limit due to the spectrum scarcity forces communication systems to utilize the spectrum resource at maximum efficiency level. One of the methods that allow effective spectrum employing is to cover multiple systems over same spectrum source by allowing bearable interference to occur between them. Femtocells have been recently introduced as a remedy to spectrum scarcity and coverage problems in current cellular structures. Femtocells are personal use base stations and they share the spectrum in a way that they can coexist with the macrocell. This thesis provides a critical reviews of different access methods in femtocell networks and further introduces improvements related to these access methods. Simulation results validate capacity improvement of proposed techniques compared to the existing access methods.
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Alghamdi, Bader A. "A Governance Method for Overcoming Cloud Computing Barriers with Architectural Requirements: Mixed Method Study Based on the Government Cloud in Saudi Arabia." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/393970.
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Despite the promising application of cloud computing within government organisations, determining the barriers to the successful implementation of cloud computing remains a major challenge. Often, government organisations face formidable barriers to fully adopting cloud computing functions. These barriers include organisational culture issues, a weak application of service-level agreements (SLAs), compliance issues, interoperability and integration issues, the lack of an organisational strategy, cost calculation methods, cloud service availability, and cloud data security and privacy, as well as insufficient trust in providers. Tackling these barriers while meeting the specifications of government cloud computing involves architectural requirements and mechanisms. In addition, the nature of cloud ecosystem operation and its alignment with appropriate strategies are known to be complex, also considering the growing desire for governance solutions. Although researchers and organisations have recognised cloud computing obstacles prior to the cloud implementation stage, fewer efforts have been made to investigate cloud barriers in-depth during and after cloud implementation projects or when introducing governance solutions. This might partly be attributable to inadequate enterprise requirements for addressing cloud barriers, the complexity of government cloud specifications, and the lack of involvement by cloud stakeholders, such as providers and consumers.
Thus, the aim of this dissertation is to develop a governance method consisting of the generation and testing of architectural requirements to overcome dominant cloud barriers and improve cloud computing functionalities in the implementation stage. To achieve this, the roles of related cloud providers and consumers have been investigated. The study was guided by activities of The Open Group Architecture Framework (TOGAF) Architecture Development Method (ADM) to design related architectural requirements that would provide best practices for the development of the governance method. Using a sequential, exploratory mixed method, multiple qualitative case studies on the role of cloud providers were conducted to explore which and how architectural requirements are suitable and applicable for addressing the identified cloud barriers. Afterwards, a quantitative survey study was performed to examine and validate the findings from the qualitative phase and to discover the role of cloud consumers in tackling cloud barriers. The utilisation of dual perspectives, from cloud providers and consumers, to design and measure the suitability and applicability of the architectural requirements is a substantial theoretical contribution in the field of enterprise information systems and cloud governance. Both cloud providers and consumers in the selected research context balanced their roles in the composition of cloud ecosystem projects, reducing complexity and enabling cooperative solutions for handling cloud barriers with different levels of emphasis and prioritisation.
The results of this thesis provide significant guidance in eliciting architectural requirements as well as in their successful contribution to addressing the 10 identified cloud barriers in the selected context. Seeking a cloud provider’s perspective through multiple case studies resulted in 24 confirmed, newly emerged architectural requirements and 48 sub-requirements for best practices to support Information Technology (IT) managers and practitioners during the implementation of government cloud projects. From the point of view of the cloud service consumer, statistical evidence showed that the architectural requirements proved to be relevant and applicable and resulted in the validation of only eight important cloud constructs with a scale of 36 architectural requirements.
The results at the governance level also produced a clear method that can enhance the realisation of value when business/IT strategies and EA governance practices both take place in cloud projects. The governance method also consists of a set of architectural requirements to support managing and controlling cloud computing implementation projects with related stakeholders and change management initiatives. The architectural requirements have been modelled via the ArchiMate 3.0 modelling language as unique and beneficial contributions for the enhancement of enterprise architecture practices. This thesis thereby introduces a novel cloud governance method with clear mechanisms and practices to serve as crucial resources for related organisations, decision-makers, business practitioners and researchers.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>School of Info & Comm Tech<br>Science, Environment, Engineering and Technology<br>Full Text
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Banai, Eyal. "Strategies to Cultivate Sustainable Open Innovation Culture in High-Tech Organizations." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5304.
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Business leaders must adopt new business practices to sustain their organizations and meet the paradigm of global competition. In the 21st century, innovation and market readiness have become the primary criteria for sustainability of an organization. Some organizational leaders should adopt open innovation strategy to stay competitive and foster a positive impact on their organizations' performance while practicing a systematic inclusion of knowledge from sources outside of the organization. The purpose of this multiple case study was to explore effective strategies business leaders use to cultivate a sustainable open innovation culture. The population consisted of leaders from 200 high technology organizations in the Washington, D.C. area. Purposeful sampling was used to select 4 organizations whose leaders demonstrated successful cultivation of open innovation culture. Schein's culture theory was the conceptual framework for this study. Data were collected through semistructured interviews and review of the organizations' annual reports, publications, websites, and brochures. Data analysis was based on Vaismoradi, Turunen, and Bondas's systematic content and thematic analysis approach, proceding from study data to codes to themes. The outcome led to 4 primary themes: organizational strategic alignment, collaboration as a force multiplier for innovation, organizational culture change, and expert understanding of the customers' needs. Implications for positive social change include fostering innovative organizations whose members bring to the market cost-effective solutions and bridge between market needs and technological solutions. Members of innovative organizations impact underserved communities in terms of material wealth, social welfare, and employment opportunities.
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Kleinfinger, Jean-François. "Modelisation dynamique de robots a chaine : cinematique simple, arborescente, ou fermee, en vue de leur commande." Nantes, 1986. http://www.theses.fr/1986NANT2060.
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Le modele dynamique est base sur trois procedes: equation generee automatiquement par calcul symbolique iteratif; formalismes recursifs de type newton-euler lineaires vis-a-vis des parametres inertiels; regroupement de parametres inertiels
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Ivanič, Michal. "Návrh testovacího stavu diferenciálu pro zástavbu v bezdozvukové komoře." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-432503.
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The diploma thesis describes the design of a test stand for experimental determination of vibroacoustic parameters of a part of the powertrain system. Thesis contains a research part, describing the problems of the drive system, vibroacoustics, measuring devices and also the division and the description of test stands. At the same time, the reasons for choosing a closed loop test stand are explained. Thesis also includes the results of analytical calculations and numerical results of FEM methods performed using ANSYS software, as well as drawing documentation of individual parts.
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Mickelsson, Glenn. "Monetary Policy in Closed and Open Economies." Thesis, Uppsala University, Department of Economics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-108006.
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<p>Two DSGE models are calibrated and simulated to investigate how the role of monetarypolicy differs between a closed and an open economy. The central bank conducts monetary policy according to a Taylor (1993) rule, reacting to inflation- and output deviations. Prices are sticky and there are habit components which slow down adjustment of consumption and exports. The models are subjected to shocks in the interest rate, inflation, technology and consumption. In most of the cases the shocks have a bigger and quicker affect on output and employment in the open economy. In connection with positive consumption- and interest rate shocks inflation is big and negative at first but gets positive already two quarters after the shock, due to effects in the exchange rate channel. In closed and open economies, a stronger reaction to output, than in the standard Taylor (1993) rule, decreases welfare losses dramatically.</p>
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Aye, Thida S. M. Massachusetts Institute of Technology. "Open vs. closed Apple music distribution platform." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45934.
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Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2008.<br>Includes bibliographical references (p. 75-77).<br>In this thesis, based on the example case study of the Apple iTunes-iPods platform technology, two simple models are analyzed to gain a better understanding of open vs. closed business models as management and market strategies for multi-sided platforms. First, a simple model of a firm with a two-sided platform serving two distinct types of customers is evaluated, assuming network effects as the only intrinsic benefits to joining such a platform. Three different cases of market structure are investigated: (i) monopoly, (ii) open duopoly (iii) closed duopoly. Using game theory, comparative results of prices, profits, consumer surplus and social welfare among the three regimes are presented. The second model focuses on the effects of competition and compatibility between a profit-maximizing closed platform and an open, freely accessible platform. Given certain conditions, it is shown that compatibility can in fact be a profitable strategy for closed platforms while improving social welfare at the same time.<br>by Thida Aye.<br>S.M.
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Caldas, Miguel, та Govindappa Navalagi. "On generalizing δ-open functions". Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/96271.
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In this paper we introduce two classes of functions called weakly δ -open and weakly δ -closed functions. We obtain their characterizations, their basic properties and their relationships with other types of functions between topological spaces.
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Haider, Jutta. "Open access and closed discourses : constructing open access as a 'development' issue." Thesis, City University London, 2008. http://openaccess.city.ac.uk/8589/.
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This thesis investigates the connection between open access - the free online availability and distribution of scientific and scholarly publications - and the 'developing world' from a post-development perspective. It takes a discourse analytical approach, drawing predominantly on Michel Foucault's understanding in discourse. It aims to answer the following questions: - Which notions of science, of development and progress, of knowledge as well as of information and technology are capitalised on in the open access debates and in which way are they shaped as a consequence? - Which discursive effects can be established, what are the results and of which kind are they? The thesis is divided into six chapters, chapters 2 to 5 are grouped into two parts. In the introduction (chapter 1) the general problem space is outlined, the connection between the open access movement and the 'developing world' is established; the research approach is briefly sketched, followed by a presentation of the research questions. Furthermore, the relevance of the study for Library and Information Science is discussed. Chapter 2 introduces the notion of discourse. It contains a discussion of the Foucauldian concept of discourse in relation to the notions of knowledge, truth, and power, as well as resistance, governmentality, and pastoral power. The manifestation of discourse in language is discussed with reference to Michel pecheux. The way in which discourses are dispersed unevenly in society is examined. It concludes with a presentation of the concept of the discursive procedure, which forms the basis for the analyses. Chapter 3 introduces post-development theory, specifically focusing on development discourse. It presents and problematises the concept of devt;lopment, of poverty and ignorance, as well as of science. The historical foundations of dev~lopmentdiscourse and the role of science and technology in it are examined. Chapter 4 investigates the representation of open access in its relation to development. It is based on a corpus consisting of 38 articles and similar publications and 5 statements and declarations. The latter are also examined from a genre perspective. The following discursive procedures are identified: (1) Leaving a blank or defining the undefinable: 111e elusiveness of the 'developing world', (2) Technologism and technological determinism, (3) Economism, (4) Scientific centralism and scientism, (5) Temporal distancing. It concludes with a discussion of the guiding metaphor, the divide. Chapter 5 investigates how open access is debated in the context of development. It draws on a two-week long email debate organised by a development institution in 2006. 146 postings by 49 participants are included in the analysis. The following discursive procedures are identified: (1) Technologism, (2) The role of the profession: mediation, translation, and control, (3) Rural people and the lack of education, (4) Developmentalism and antidev~ lopmentalism: Positioning oneself in and against development. It concludes with a discussion of the guiding metaphor, the barrier, as well as ofidentity construction. The concluding chapter 6 is concerned with providing a sum-up of the analyses with a view to answering the research questions. It considers a possible future for the open access movement in its relation to the 'developing world' and concludes with a brief discussion of issues relevant for future research. The main findings suggest that the 'developing world' is constructed around the coordinates provided by mainstream development thought. Open access is inserted into its discursive repertoire as a problem of development, a tool for its delivery, and its measure. The dominant understanding of information adheres to a sender/receiver model. However, ruptures occur in significant places. This requires a partial re-positioning of the way in which development is framed and of open access' role in it.
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Lövgren, Johan. "Food web dynamics in open and closed systems." Doctoral thesis, Umeå University, Ecology and Environmental Science, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-269.
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<p>This thesis is a summary of enclosure and microcosm experiments that aimed to study the impact of allochtonous subsidies on food web dynamics in a heterogeneous food web. In the enclosure studies, a three trophic level littoral food web was used. The food web consisted of two growth forms of primary producers: phytoplankton and periphyton and their associated herbivores: scraping and filtering herbivores. The predator used, YOY perch, affects both pathways in the food web. Manipulation of the openness for the different trophic levels showed that the inflow of phytoplankton and cross-habitat foraging by the herbivore level reinforced the compensatory response between the two growth forms of primary producers </p><p>In the microcosm experiment, the response of an herbivore food web and a microbial community to inflow of resources and food web configuration was studied, using a model food web. The model food web consisted of two forms of primary producers, i.e. phytoplankton and periphyton, and two herbivores, i.e. <i>Daphnia pulex</i> feeding on phytoplankton, and <i>Chydorus sphaericus</i> feeding on both periphyton and phytoplankton. Three different food web configurations, all having the phytoplankton and periphyton, but either one of the herbivores, or both, were set up. The flow regimes consisted of an open treatment receiving a constant supply of phytoplankton, and a closed treatment with an initial resource pool. The effect of the inflow of phytoplankton was affected by the food web configuration. In the presence of <i>D. pulex</i>, the inflow of phytoplankton was made accessible to periphyton, and indirectly to <i>C. sphaericus</i>, which increased to such high densities that <i>D. pulex</i> was negatively affected. The inflow of phytoplankton had an indirect negative effect on the microbial community, since the biomass of herbivores increased, which imposed a higher grazing pressure on all parts of the microbial community.</p>
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Lövgren, Johan. "Food web dynamics in open and closed systems /." Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-269.
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Baumgartl, Marcus. "On the correspondence of open and closed strings." Diss., München Verl. Dr. Hut, 2007. http://d-nb.info/988229242/04.
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Tran, Mai. "Mobile WiMAX Open and Closed Loop MIMO Evaluation." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520187.
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Özkan, Gülçin. "Macroeconomic policy games in closed and open economies." Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297140.
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Baumgartl, Marcus. "On the correspondence of open and closed strings." München Hut, 2008. http://edoc.ub.uni-muenchen.de/8684/.
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Guidi, Hernan. "Open and closed-loop model identification and validation." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-07032009-170311/.
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Ganelli, Giovanni. "Fiscal policy in new open economy macroeconomics models." Thesis, University of Warwick, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269119.
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Lindgren, Sophie. "Open and closed endotracheal suctioning : experimental and human studies /." Göteborg : Dept. of Anaestesiology and Intensive Care, Institute of Clinical Sciences, Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/3325.
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Herzog, Philipp. "Open and closed innovation different cultures for different strategies." Wiesbaden Dt. Univ.-Verl, 2007. http://d-nb.info/987522531/04.
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Herzog, Philipp. "Open and closed innovation : different cultures for different strategies." Wiesbaden Gabler, 2008. http://d-nb.info/987522531/04.
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Lauda, Aaron Dean. "Open-closed topological quantum field theory and tangle homology." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614322.
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Azevedo, Thales [UNESP]. "Open-closed superstring amplitudes using vertex operators in AdS5xS5." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/127895.
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000848245.pdf: 624236 bytes, checksum: c69b524f4c9580903dec4bfab14e6987 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>Nestatese, uma dada amplitude de espalhamento de supercordas envolvendo um operador de vértice da corda fechada e N operadores de vértice da corda aberta em AdS5 ×S5 é detalhadamente estudada, utilizando-se o formalismo de espinores puros. Após rever o material de apoio e realizar alguns cálculos preliminares, mostramos que a amplitude nível-de-árvore contendo um estado de supergravidade e N estados de super-Yang-Mills localizados em uma D3-brana próxima à fronteira de AdS5 pode ser expressa como uma integral no superespaço harmônico N = 4, d = 4 em termos dos supercampos de supergravidade e super-Yang-Mills, demonstrando assim uma conjectura feita recentemente<br>In this thesis, a particular superstring scattering amplitude involving one closed string and N open string vertex operators in AdS5 ×S5 is studied in detail, usingthe pure-spinor formalism. After reviewing some background material and performing a few preliminary calculations, we show that the tree-level amplitude containing one supergravity state and N super-Yang-Mills states located on a D3-brane near the AdS5 boundary can be expressed as an N = 4, d = 4 harmonic superspace integral in terms of the supergravity and super-Yang-Mills superfields, thus proving a conjecture recently made<br>FAPESP: 2010/19596-2
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Azevedo, Thales Agricola Calixto de. "Open-closed superstring amplitudes using vertex operators in AdS5xS5 /." São Paulo, 2015. http://hdl.handle.net/11449/127895.
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Orientador: Nathan J. Berkovits<br>Banca: Andrei Mikhailov<br>Banca: Horatiu Nastase<br>Banca: Diego Trancanelli<br>Banca: Nelson Braga<br>Resumo: Nestatese, uma dada amplitude de espalhamento de supercordas envolvendo um operador de vértice da corda fechada e N operadores de vértice da corda aberta em AdS5 ×S5 é detalhadamente estudada, utilizando-se o formalismo de espinores puros. Após rever o material de apoio e realizar alguns cálculos preliminares, mostramos que a amplitude nível-de-árvore contendo um estado de supergravidade e N estados de super-Yang-Mills localizados em uma D3-brana próxima à fronteira de AdS5 pode ser expressa como uma integral no superespaço harmônico N = 4, d = 4 em termos dos supercampos de supergravidade e super-Yang-Mills, demonstrando assim uma conjectura feita recentemente<br>Abstract: In this thesis, a particular superstring scattering amplitude involving one closed string and N open string vertex operators in AdS5 ×S5 is studied in detail, usingthe pure-spinor formalism. After reviewing some background material and performing a few preliminary calculations, we show that the tree-level amplitude containing one supergravity state and N super-Yang-Mills states located on a D3-brane near the AdS5 boundary can be expressed as an N = 4, d = 4 harmonic superspace integral in terms of the supergravity and super-Yang-Mills superfields, thus proving a conjecture recently made<br>Doutor
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Chan-Lang, Solène. "Closed and Open World Multi-shot Person Re-identification." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066389/document.
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Dans cette thèse, nous nous sommes intéressés au problème de la ré-identification de personnes dans le cadre de bases d'identités ouvertes. Ré-identifier une personne suppose qu'elle a déjà été identifiée auparavant. La galerie fait référence aux identités connues. Dans le cas de bases d'identités ouvertes, la galerie ne contient pas toutes les identités possibles. Ainsi une personne requête peut être une des personnes de la galerie, mais peut aussi ne pas être présente dans la galerie. Ré-identifier en base ouverte consiste donc non seulement à ranger par ordre de similarité les identités galeries les plus semblables à la personne requête mais également à rejeter les personnes requêtes si elles ne correspondent à aucune personne de la galerie. Une de nos contributions, COPReV, s'appuie exclusivement sur des contraintes de vérification afin d'apprendre une projection des descripteurs telle que la distance entre les descripteurs d'une même personne soit inférieure à un seuil et que la distance entre les descripteurs de deux personnes distinctes soit supérieure au même seuil. Nos autres contributions se basent sur des méthodes parcimonieuses collaboratives qui sont performantes pour résoudre des tâches de classement. Nous proposons d'améliorer ces méthodes en introduisant un aspect vérification grâce à une collaboration élargie. De plus, une variante bidirectionnelle de cette approche la rend encore plus robuste et donne des résultats meilleurs que les autres approches actuelles de l'état de l'art dans le cadre de la ré-identification de personne en base d'identités ouverte<br>In this thesis we tackle the open world person re-identification task in which the people we want to re-identify (probe) might not appear in the database of known identities (gallery). For a given probe person, the goal is to find out whether he is present in the gallery or not and if so, who he is. Our first contribution is based on a verification formulation of the problem. A linear transformation of the features is learnt so that the distance between features of the same person are below a threshold and that of distinct people are above that same threshold so that it is easy to determine whether two sets of images represent the same person or not. Our other contributions are based on collaborative sparse representations. A usual way to use collaborative sparse representation for re-identification is to approximate the feature of a probe image by a sparse linear combination of gallery elements, where all the known identities collaborate but only the most similar elements are selected. Gallery identities are then ranked according to how much they contributed to the approximation. We propose to enhance the collaborative aspect so that collaborative sparse representations can be used not only as a ranking tool but also as a detection tool which rejects wrong matches. A bidirectional variant gives even more robust results by taking into account the fact that a good match is a match where there is a reciprocal relation in which both the probe and the gallery identities consider the other one as a good match. COPReV shows average performances but bidirectional collaboration enhanced sparse representation method outperforms state-of-the-art methods for open world scenarios
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Muraro, Gularte Kevin Herman. "Open- and closed-loop identification using artificial neural networks." reponame:Repositório Institucional da UnB, 2017. http://repositorio.unb.br/handle/10482/31607.
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2017.<br>Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2018-03-29T18:46:44Z
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Previous issue date: 2018-04-10<br>Este trabalho apresenta vários esquemas para identificação, observação e controle adaptativos em tempo real de sistemas não lineares incertos usando redes neurais artificiais. Com base na teoria de estabilidade de Lyapunov, e usando resultados já disponíveis na teoria de controle adaptativo, são propostos esquemas para identificação, observação e controle nos quais os erros de identificação, observação e rastreamento estão relacionados com parâmetros de projeto que podem ser ajustados diretamente pelo usuário. Entretanto, ao contrário das propostas usuais na literatura, este trabalho propõe algoritmos nos quais o desempenho transiente e em regime podem ser desacoplados e ajustados independentemente através de parâmetros de projeto independentes. Inicialmente, o caso de identificação em tempo real é considerado, uma vez que cada vez mais a resolução de sistemas caixa preta tem sido demandados. O identificador proposto apresenta as seguintes peculiaridades: 1) Possibilidade de controlar o tamanho do erro residual de estado a partir de matrizes de projeto; 2) Possibilidade de ajustar a duração do regime transiente a partir de um parâmetro de projeto que é independente do tamanho do erro em regime. A identificação de um sistema caótico de três estados foi considerada para validar o esquema. A seguir, o resultado é estendido para o caso nos quais alguns estados não estão disponíveis para medida. Para tanto, é necessário apenas fazer alguns ajustes no esquema de identificação proposto, para permitir agora estimar um ou mais estados não disponíveis para medição, a partir das entradas e saídas ao sistema. O observador proposto apresenta as mesmas peculiaridades do identificador. A observação de um sistema de Rössler foi implementada de forma a exemplificar este observador. Na sequência, considera-se o caso de controle com realimentação do estado. Para tanto, se propôs o projeto do controlador empregando como base o caso de identificação de malha aberta. As principais peculiaridades do identificador ocorrem também no controlador. Finalmente, de modo a ressaltar a aplicabilidade e relevância dos algoritmos propostos, a identificação e controle de um sistema de soldagem foram realizados. A dissertação está organizada da seguinte forma. O capítulo 1 apresenta a introdução, motivação, objetivo, possíveis contribuições e estrutura do trabalho proposto. No capítulo 2 é apresentada uma revisão do estado da arte dos métodos de identificação, observação e controle baseados em redes neurais artificiais. No capítulo 3, usando a teoria de estabilidade de Lyapunov, propõe-se um esquema de identificação neural adaptativo em tempo real para uma classe de sistemas não lineares na presença de distúrbios limitados. É importante ressaltar que nenhum conhecimento prévio sobre a dinâmica do erro de aproximação, pesos ideais ou perturbações externas é necessário. Mostra-se que o algoritmo de aprendizado baseado na teoria de estabilidade de Lyapunov leva o estado estimado a convergir assintoticamente para o estado de sistemas não lineares. O algoritmo proposto permite: 1) reduzir o erro residual de estimação de estado para valores pequenos por meio de matrizes de projeto; 2) controlar o tempo de transiente de maneira arbitraria a partir de um parâmetro de projeto. Foram feitas simulações para um sistema caótico de 3 estados e para um sistema hipercaótico de 4 estados para demonstrar a eficácia e a eficiência do algoritmo de aprendizado proposto. Nessas simulações foram feitas análises do tamanho do erro residual de estado e da escolha do tempo de transiente. Finaliza-se o capítulo com uma aplicação: a identificação neural de um sistema caótico de soldagem na qual se analisou o ajuste do tamanho do erro residual de estado. Posteriormente, no capítulo 4, os resultados obtidos no capítulo anterior são estendidos para um sistema de observação neural. O caso de observação ocorre quando nem todos os estados estão disponíveis e um ou mais estados precisam ser estimados. A metodologia de projeto do algoritmo de aprendizado é semelhante ao caso do capítulo 3, sendo necessário fazer algumas adaptações próprias para um esquema de observação. Mais especificamente, a ideia principal consiste em expressar o erro de estimação de estado, que não é mais disponível para medida, em função do erro de estimação da saída. Para tanto, faz-se necessária a imposição de uma hipótese de detectabilidade e de uma outra condição matricial que devem ser satisfeitas simultaneamente para que o esquema de observação apresente características de estabilidade e convergência semelhantes ao esquema de identificação proposto. Realiza-se no final do capítulo a observação de um sistema caótico de Rössler sob a presença de distúrbios externos com controle do tempo de transiente. No capítulo 5, os resultados do capítulo 3 são estendidos para controlar sistemas não lineares afins no controle. O caso de controle ocorre quando se realiza uma identificação em malha fechada, ou seja, há uma realimentação no sistema. Mais exatamente, através da realimentação objetiva-se cancelar as não lineares desconhecidas no sistema que podem ser parametrizadas por uma rede neural artificial. Dessa maneira, a equação de erro de restreamento pode ser reescrita com uma estrutura similar à equação de erro de estimação do caso de identificação. Com a finalidade de ressaltar a aplicabilidade do esquema de controle proposto, para situações de interesse industrial, realiza-se a simulação do controle de um sistema de soldagem com tranferência globular-spray em um processo GMAW (Soldagem por arco elétrico com gás de proteção). Finalmente, no capítulo 6 resume-se as contribuições da pesquisa, os resultados obtidos, e sugestões para pesquisas futuras são discutidas. A fundamentação teórica das redes neurais artificiais (incluindo suas propriedades), dos algoritmos de aprendizado e da teoria de estabilidade de Lyapunov são descritas no apêndice 1, assim como outras informações importantes que embasam os capítulos do trabalho. O apêndice 2 contém os códigos utilizados para implementação do identificador, observador e controlador propostos nesta dissertação.<br>This work presents several schemes for online identification, observation, and adaptive control of uncertain nonlinear systems by using artificial neural networks in which the transient and residual errors can be independently adjusted. Based on Lyapunov theory, and using results already available in adaptive control theory, schemes for identification, observation, and control are proposed. However, unlike other works in the literature, the identification model, learning algorithm, and control laws are designed to decouple the transient and residual state performance, which is accomplished through the manipulation of independent design parameters. Initially, the case of online identification is considered, since black-box systems can be parameterized by neural networks and these parameterizations are needed to tackle more complex problems, such as observation and adaptive control. The proposed identifier has the following peculiarities: 1) Possibility to control the size of residual state error from design matrices; 2) Possibility to adjust the duration of the transient regime from a design parameter regardless of the size of the regime error. The identification of a chaotic system of three states was considered to apply the scheme. The result is then extended to the case where some states are not available for measurement. To do so, it is only necessary to make some adjustments in the identification scheme. Basically, the state error is placed as a function of the output error, which is available for measurement. The main characteristic of the proposed observer is the preservation of the properties of the proposed identifier. The observation of a Rössler system was implemented in order to exemplify this observer. In the sequence, the case of control with state feedback is considered. For this, a controller was proposed using the open loop identification case as analogue to it. The main peculiarities of the identifier also occur in the controller. Finally, in order to emphasize the applicability and relevance of the proposed algorithms, the identification and control of a welding system were performed.
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Ghosh, Sugata. "Aspects of macroeconomic policy in closed and open economies." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321337.
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Vromans, Deborah Claire. "Macrophyte phenology in a temporarily open/closed Estuary compared with a permanently open Estuary." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1393.
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Temporarily open/closed estuaries (TOCEs) are unpredictable environments that change in response to mouth condition, which is influenced by freshwater flooding or sea storm surges. The aim of the study was to determine whether macrophyte phenology in a TOCE was event driven rather than cyclically predictable and if it differed from permanently open estuaries (POEs). Macrophyte growth and flowering phenology in response to environmental conditions was investigated in the East Kleinemonde Estuary (TOCE) and the Kowie Estuary (POE) along the eastern coastline of South Africa. The lack of freshwater flooding due to low rainfall coupled with several overwash events resulted in a prolonged period of mouth closure from September 2008 to the end of this study period in 2010. This in turn caused the inundation of the supratidal and intertidal habitats, high water level (> 1.57 m amsl) and high salinity (30 - 42 ppt) in the TOCE. Principle Components Analysis showed that high water level and reduced sediments were the most significant environmental factors affecting macrophyte phenology. Macrophyte phenology in the POE was primarily driven by temperature, sediment redox potential and salinity. The saline high water level and reduced sediment significantly reduced macrophyte cover in all habitats in the TOCE. Macrophytes in the POE maintained high cover abundance due to seasonal re-growth compared to the TOCE where cover declined over the sampling period due to the high water level. Subsequent to water level dropping by as little as 11 - 20 cm in the TOCE, the intertidal species Sarcocornia tegetaria and Salicornia meyeriana completed their life-cycles and produced viable seeds within four and three months of germinating respectively. In contrast, the Sarcocornia hybrid and S. meyeriana in the POE took longer to complete their life-cycles, namely seven and nine months respectively, while S. tegataria did not germinate in situ but reproduced vegetatively despite producing seed. In the TOCE, the submerged species Ruppia cirrhosa and Chara vulgaris completed their life-cycles within five and three months and produced a maximum of 26 242 and 196 998 seeds m-2 respectively. Due to high water level and prolonged inundation, the reproductive periods were shorter for the intertidal and reed and sedge species in the TOCE compared to the POE. Seed output during the two reproduction periods varied between the two estuaries. Sarcocornia decumbens and S. tegetaria produced a substantially higher number of seeds in the TOCE compared to the POE, namely 0 - 102 847 versus 20 661 - 48 576 seeds m-²; and 7 001 - 45 542 versus 1 587 – 16 958 seeds m-² respectively. Seed output in the TOCE was significantly higher in S. tegetaria during the second reproduction period despite the significantly lower plant cover, which may be a function of the stressful environment in the TOCE. Seed production of S. meyeriana was significantly higher in the POE compared to the TOCE, with 264 224 - 640 292 compared with 24 050 - 27 643 seeds m-², due to higher plant cover in the POE. The research suggests that macrophyte phenology in the TOCE was significantly influenced by mouth condition. Further, macrophytes were able to demonstrate considerable phenotypic plasticity in response to changing and unfavourable environmental conditions. These data can be used in mouth management plans and freshwater requirement studies in TOCEs to ensure that macrophytes can complete their life-cycles and produce viable seeds for the safeguarding of habitat persistence and ecological processes. In impacted estuaries where artificial mouth opening is practised and the macrophytes have been severely degraded or extirpated, management should ensure that the intertidal and supratidal habitats are not inundated during peak flowering and seed production periods i.e. late spring to early autumn (November to March).
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Drhourhi, Allal. "Croissance en phase vapeur par flux force : application aux depots de monocristaux de tib::(2) en systeme ouvert et films de ni en systeme ferme." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21036.
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Elaboration par depot chimique et transport chimique en phase vapeur des monocristaux tib::(2). Comparaison entre les deux methodes. Developpement d'un plan de travail pour obtenir des depots reproductibles. Etude du systeme ni/nio::(4) en tube scelle. Comparaison avec le systeme ouvert. Analyse du transport des flux. Elaboration du modele du transport des flux
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DeGrace, Carl W. "Sinking a body with bubbles in closed and open environments." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA386031.
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Allitt-Wheeler, Susan Lorber Michael A. "Comparison of student achievement in open versus closed computer laboratories." Normal, Ill. : Illinois State University, 2005. http://wwwlib.umi.com/cr/ilstu/fullcit?p3196637.
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Thesis (Ed. D.)--Illinois State University, 2005.<br>Title from title page screen, viewed September 27, 2006. Dissertation Committee: Michael A. Lorber (chair), Joaquin A. Ruiz-Vila, Temba Bassoppo-Moyo, Adel Al-Bataineh. Includes bibliographical references (leaves 66-70) and abstract. Also available in print.
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Knorr, Matthias. "Combining open and closed world reasoning for the semantic web." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/6702.
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Dissertação para obtenção do Grau de Doutor
em Informática<br>One important problem in the ongoing standardization of knowledge representation
languages for the Semantic Web is combining open world ontology languages, such as the OWL-based ones, and closed world rule-based languages.
The main difficulty of such a combination is that both formalisms are quite orthogonal w.r.t. expressiveness and how decidability is achieved. Combining non-monotonic rules and ontologies is thus a challenging task
that requires careful balancing between expressiveness of the knowledge representation language and the computational complexity of reasoning.
In this thesis, we will argue in favor of a combination of ontologies and nonmonotonic
rules that tightly integrates the two formalisms involved, that has a computational complexity that is as low as possible, and that allows us to query for information instead of calculating the whole model. As our starting point we choose the mature approach of hybrid MKNF knowledge
bases, which is based on an adaptation of the Stable Model Semantics to knowledge bases consisting of ontology axioms and rules. We extend the two-valued framework of MKNF logics to a three-valued logics, and we propose a well-founded semantics for non-disjunctive hybrid MKNF knowledge bases. This new semantics promises to provide better efficiency of reasoning,and it is faithful w.r.t. the original two-valued MKNF semantics and compatible with both the OWL-based semantics and the traditional Well-
Founded Semantics for logic programs. We provide an algorithm based on operators to compute the unique model, and we extend SLG resolution with tabling to a general framework that allows us to query a combination of non-monotonic rules and any given ontology language. Finally, we
investigate concrete instances of that procedure w.r.t. three tractable ontology
languages, namely the three description logics underlying the OWL 2 pro les.<br>Fundação para a Ciência e Tecnologia - grant contract SFRH/BD/28745/2006
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Power, Simon C. "Mechanisms determining the coexistence of open- and closed-canopy biomes." Thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/28394.
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Open- (e.g. grassland, savanna, shrubland) and closed-canopy (e.g. forest) biomes frequently coexist in the same landscape, where open environments tend to be fire-prone with higher light, but lower nutrient and water availability than closed environments. Environmental heterogeneity could select for divergent floristic assemblages and adaptive traits, from which emergent differences in resource availability and fire incidence contribute to excluding species from the alternate habitat. In this thesis, I investigated whether the coexistence of open–closed canopy biomes, such as forest and fynbos in the Cape Floristic Region, is contingent on environmental heterogeneity coupled with contrasting species traits. Given the heterogeneity in multiple environmental properties between open- and closed-canopy biomes, I hypothesized that boundaries between open- and closed-canopy biomes will display greater floristic turnover compared to boundaries between structurally similar biomes (e.g. open- and opencanopy biomes). To explore this, genus- and family-level turnover were correlated with climate, fire, leaf area index (LAI: proxy for understorey light) and soil properties across biome boundaries in South Africa. Both genus- and family-level turnovers were highest across open–closed boundaries and most strongly predicted by increased differences in LAI, suggesting that contrasting light regimes provide significant adaptive challenges for plants. The potential effect of contrasting light regimes is highlighted by the absence of open-canopy species from forest understoreys, where low, dynamic light could limit the ability of plants to acquire sufficient carbon. This apparent shade intolerance led to the hypothesis that open-canopy species lack the traits to maintain a positive carbon balance under low and dynamic light. To test this, leaf traits and photosynthetic response to continuous or dynamic light were compared between forest and fynbos species grown under three light treatments. Fynbos species experienced high mortality under shade treatments, produced leaves that were thicker, up to 1000 times smaller, had lower photosynthetic rates (0.8 versus 3.4mol m-2 s -1 ) under continuous low light (400 mol m-2 s -1 ) and lower light-use efficiency during dynamic light sequences than forest species. These differences imply that shade intolerance in fynbos species is associated with traits that are inefficient at harvesting light and require relatively continuous high intensity light for carbon assimilation. Moreover, these inefficiencies would make it difficult to support the carbon intensive traits (e.g. cluster roots, lignotubers, sclerophyllous leaves) that facilitate fire survival and nutrient acquisition/conservation in open habitats. In contrast, forest species are able to colonize open habitats during the long-term absence of fire, implying that they are able to tolerate high light and low nutrient conditions. Given that plants frequently cope with contrasting conditions through the expression of phenotypic plasticity, it was hypothesized that closed-canopy species possess greater plasticity than open-canopy species. To assess this, the response of leaf traits and foliar nutrition to changes in LAI and soil nutrition were compared between forest and fynbos species in the field. Leaf size and specific leaf area in forest species correlated positively with LAI and soil nutrition, whereas fynbos species response was weak, suggesting that forest species are more plastic. This plasticity may be realised by the variable light conditions forest species experience through their canopy and the occupation of higher nutrient soils, which alleviate belowground constraints. By comparison, the occupation of low nutrient soils by fynbos may inhibit plasticity given the selection of inflexible, conservative leaves. Consequently, I propose that the coexistence of open- and closed-canopy biomes arises from the steep turnover in selective regimes, which together with the contrasting adaptive traits and degrees of phenotypic plasticity they require, act together to competitively exclude species from the alternate habitat.
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Lin, Nanjou. "Dynamics and control of open- and closed-chained multibody systems." Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1056555546.
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Lust, Kathleen R. "The effects of a six week open kinetic chain/closed kinetic chain and open kinetic chain/closed kinetic chain/core stability strengthening program in baseball." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5173.
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Nylén, Daniel. "From closed to open : ICT as an Enabler for Creating Open Innovation Systems in Industrial Settings." Thesis, Umeå University, Department of Informatics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-26660.
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<p>Most forestry machines being produced today include a PC that monitors and controls the harvester head, and an information system that stores data on every action the driver or the machine performs. ICT thus provides an opportunity to improve efficiency and competitiveness and possibly also opens up for new ways of working for actors in the forestry industry. The purpose of this study is to investigate how ICT can enable the transformation from selling products to selling services in the forestry industry. We investigate this through performing a Case Study including a number of actors from the Forestry industry in northern Sweden. First, we investigate the barriers for establishing an Open Innovation system in forestry. Then we describe the main steps to be taken and how the use of ICT can enable the establishment of such a system. The case study shows that the forestry industry is committed to working according to a traditional value chain and is committed to a closed innovation paradigm. We argue that the ICT component in Timbercut’s forestry machines constitutes a latent potential that cancaptured through changing the business model and setting up a joint venture with Rewire.</p>
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Li, Jun. "ARTIN PRESENTATIONS AND CLOSED 4-MANIFOLDS." Oberlin College Honors Theses / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin14975050044205.
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Hanbury, Elizabeth. "Homology stability of mapping class groups and open-closed cobordism categories." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496906.
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Palmer, Deborah L. "Should Bedroom Doors be Open or Closed while People are Sleeping?" University of Canterbury. Civil Engineering, 1999. http://hdl.handle.net/10092/8287.
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Traditionally the New Zealand Fire Service has been giving the advice to the New
Zealand public that it is safer to sleep with their bedroom doors closed. The advice given is not backed up by any technical evidence that it is the best way to position your bedroom door when asleep. Sleeping with your bedroom door closed reduces smoke migration into the bedroom. With the increased use of simple, cheap smoke alarms in many residential houses, it is important to investigate if this is the safest way to position your door when asleep.
The aim of this research is to determine whether it is safer to sleep with bedroom doors open or closed in the event of a fire by performing a probabilistic risk assessment. The recommendation made by this research can be used by Fire Services to give the best advice on whether it is safer to sleep with bedroom doors open or closed. The analysis is carried out using two methods. Firstly by evaluating the expected risk to life to occupants by using FiRECAM (Fire Risk Evaluation and Cost Assessment Model), which is being developed at the National Research Council of Canada. The second method used determines the probability of failure using an event tree method.
Both analyses recommend that it is safer to sleep with bedroom doors closed while sleeping. Although they agree with each other there are many issues requiring further investigation in both analyses. The results of the analyses are only comparable in a relative sense and are not yet able to be compared in absolute terms.
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Kent, Adam. "Influence of recruitment on population persistence in open and closed systems." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340661.
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Jalkh, Pierre E. (Pierre Edovard). "Open loop and closed loop cup forming of aluminum sheet metals." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/35953.
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Shawcross, Anna. "Infant multiple breath washout using a novel open-closed circuit system." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/infant-multiple-breath-washout-using-a-novel-openclosed-circuit-system(06f61a8a-f731-4a60-b0fe-ad330582d7bd).html.
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Background: Lung clearance index (LCI), obtained by multiple breath washout testing (MBW), is a sensitive measure of lung disease in infants. It has been identified as a particularly suitable endpoint for clinical trials in cystic fibrosis (CF), but has potential applications in many other conditions. However, MBW in infants presents a number of technical challenges. Conventional MBW is based on simultaneous measurement of flow and gas. These two signals are then aligned and combined to derive expired gas volumes and measures of ventilation inhomogeneity: this process becomes increasingly vulnerable to errors in gas signal alignment at rapid respiratory rates. At present, no existing system for infant MBW meets all the criteria set out in international guidelines, and there is no simple method of assessing lung function outside research laboratories in this population. This thesis describes an alternative method of performing MBW in infants. In this method, expired gas is collected and analysed to derive functional residual capacity (FRC) and LCI. There is no need to simultaneously measure flow, and therefore no need for the complicated step of integrating flow and gas signals. Dead space is also significantly reduced by removing the flowmeter. Methods: In the first phase of testing, an existing lung model was modified to generate realistic infant breathing parameters with high accuracy. The prototype system was modified to improve accuracy and subsequently tested at FRC of 100-250mls with respiratory rates of 20-60min-1. In the second phase, testing proceeded to an in vivo pilot study of the novel method in children with cystic fibrosis and healthy controls. Practical applicability of the system was determined by the number of successful duplicate tests, and within-subject repeatability. Comparison was made with LCI measurements obtained using a respiratory mass spectrometer, currently considered the gold standard for infant LCI. Results: In a total of 103 tests performed in the lung model, overall mean error (standard deviation) of FRC measurement was -1.0(3.3)%, with 90% of tests falling within +/-5%. 13 patients were excluded from the clinical study due to being unsedated or inadequately sedated and therefore failing to tolerate the test. A total of 25 patients (7 children with CF, 18 healthy control children) were deemed to be adequately sedated at the start of the test, of these 20 patients (7 with CF) successfully underwent duplicate testing (80% success rate). Mean FRC for healthy controls was 19.5ml/kg, and mean LCI 6.45. For children with CF, mean FRC was 21.8ml/kg and mean LCI 6.98. Mean within-subject coefficient of variation for FRC was 7.18% and for LCI 5.94%. Of 4 infants assessed with both the novel method and the respiratory mass spectrometer, there was good correlation in FRC measurement (mean difference -8.1%). Comparison of LCI with the mass spectrometer was affected by technical difficulties with the test; in those patients who underwent technically adequate tests with both methods, mean difference in LCI between the two methods was 1.65%. Discussion: FRC measurement using the novel method has superior accuracy in vitro than previously described systems. Data from the pilot study suggest that this is a feasible and reproducible method of performing LCI in infants and young children, as long as they are adequately sedated. Results in both children with CF and controls fall within the expected range, and well within accuracy limits set by international guidelines. However, the system and testing protocol could be further improved to reduce the number of technically inadequate tests having to be excluded. This could provide a more accessible alternative to previously described systems for infant MBW.
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Cowley, Paul D. (Paul Denfer) 1964. "Fish population dynamics in a temporarily open/closed South African estuary." Thesis, Rhodes University, 1999. http://hdl.handle.net/10962/d1008543.
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The primary aim of this study was to investigate the population dynamics of the fishes associated with a small (17.5 hectares) temporarily open/closed estuary on the south east coast of South Africa. The results are based on the findings of an intensive sampling programme conducted over a period of four years in the East Kleinemonde estuary (33° 32' S : 27° 03' E). By adopting a quantitative approach, this study addresses the need for information on estuarine-associated fish population sizes, standing stock (biomass) estimates and productivity. The ichthyoplankton assemblage in the surf zone adjacent to the mouth of the estuary was dominated by postflexion larvae representing at least 21 taxa in 14 families. Rhabdosargus holubi of sizes ranging between 9 mm and 21 mm BL was the most abundant species with a mean density of 7.3 individuals per 100 m'. This species, which accounted for 77.6% of the catch composition, was recorded throughout the year but revealed a distinct peak in abundance in spring (August - September). The ichthyofaunal community within the East Kleinemonde estuary was dominated by juvenile marine-spawning species and typical of a warm temperate southern African estuary. A total of 30 species in 17 families was recorded, including the endangered estuarine pipefish Syngnathus watermeyeri. Multivariate analyses (classification and ordination) of the catch assemblages revealed a high degree of similarity (> 70%) throughout the estuary, with two distinct groups being identified on the basis of substratum type. The sampling stations near the mouth with a sandy substratum were distinguished from all other sampling sites in the estuary. The dominant estuarine-spawning species were represented by all life-history stages, suggesting that they bred successfully in the estuary. This group was numerically and gravimetrically dominated by the two zooplanktivorous shoaling species Gilchristella aestuaria and Atherina breviceps with density extrapolated population size estimates of 420 973 and 198 275 individuals, and biomass estimates of 1.6 and 0.6 g m⁻² respectively. The total population size of all estuarine-spawning species with a mean biomass 00.4 g m⁻² was estimated at 754 217 individuals. Population size estimates of the marine-spawning species were calculated using data obtained from three independent mark-recapture experiments. The assumptions for the mark-recapture analyses were adequately met and it was concluded that the techniques provided reliable estimates of population size. However, estimates obtained from density extrapolation revealed enormous variability and were considered to be unreliable. The total population size was estimated at 63 342, 18 592 and 13 5 192 during the three mark-recapture experiments respectively. The numerically dominant species during all three experiments was Rhabdosargus holubi. Biomass production of the marine-spawning species was evaluated over a 123 day census period when population sizes and estimates of growth rates were known. Productivity for all fishes with a standing stock of 26.2 g m⁻² was calculated at 4.5 g m⁻² month01 Rhabdosargus holubi accounted for more than 75% of the total marine fish productivity. This study draws attention to the success of Rhabdosargus holubi in the East Kleinemonde estuary, which is ascribed to aspects of its biology. These include an extended breeding season, the ability to recruit into the estuary under adverse open mouth conditions and its omnivorous food habits. The dominance of this migratory species suggests that it plays an important role in the transfer of energy to the coastal marine environment when the mouth of the East Kleinemonde estuary opens. Predation by birds and a dominant piscivorous fish (Lichia amia) was quantitatively assessed over a period of two years. Monthly food consumption by all piscivorous birds revealed large temporal variability, ranging from 32 to 466 kg month-I An unusual invasion of Cape cormorants during the winter of 1994 accounted for large scale mortality (2246 kg of fish) over a relatively short period. The predatory impact of this episodic event was reflected in the findings of the fish mark-recapture experiments, which revealed a 70% reduction in the total population of marine-spawning fishes (above a certain minimum size) in the estuary subsequent to this invasion. Monthly food consumption by the Lichia amia population in the estuary was calculated at 68 and 58 kg month-I for two distinct time periods when the population size was known. These findings suggest that this species is the top piscivorous predator in the East Kleinemonde estuary. Finally, the findings of this study highlight the temporal variability of fish populations within a single estuary. It is suggested that predation and estuary mouth conditions are the main factors influencing the abundance (and its variability) of individual species in the East Kleinemonde estuary.
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Moraes, Karlos Ribeiro de. "Quality comparison of sole from wild/farmed and closed/open circuits." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/8536.
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Mestrado em Ciências do Mar e Zonas Costeiras<br>Soles (Solea spp) are a high-value commercial group of species with increasing importance in aquaculture. Common quality evaluation methods were used to compare Solea solea and Solea senegalensis sampled from the natural environment and fish farms. The aim was to develop a series of experiments and analysis of wild and farmed fish in Portugal, during 31 days, during boxed and iced storage. The analyses were performed using physical evaluations with Torrymeter type 295 and RT-Freshmeter type RT-2E, each 2 days and sensory evaluations using QIM (Quality Index Method), every day. The results show that farmed fish has a slower decrease in instrumentally-measured properties than the farmed, and QIM results show a loss in appearance more evident in the wild samples. For more accurate results, complementary analysis, like chemical, histological and microbiological, become necessary.<br>As solhas (Solea spp) são um grupo de espécies de alto valor comercial com crescente importância na aquicultura. Métodos de avaliação da qualidade comuns em pescado foram usados para comparar a qualidade da solha. Solea solea e Solea senegalensis foram amostrados do ambiente natural e aquiculturas. Os peixes passaram por uma série de testes com o objetivo de analisar a sua qualidade. As amostras de peixes selvagens e de cultura, obtidas em Portugal, foram analisadas durante 31 dias, ao longo da sua degradação em caixas e em gelo moído. Foram feitas avaliações com os aparelhos Torrymeter 295 e RT-Freshmeter RT-2E, a cada dois dias, e avaliações sensoriais com o esquema QIM (Quality Índex Method), todos os dias. Os resultados mostram que os peixes de aquacultura têm uma perda mais lenta de qualidade do que os selvagens, em ambas as análises instrumentais, e nas análises do QIM mostram uma perda de qualidade na aparência mais evidente nos os selvagens. Para resultados mais precisos, análises complementares, como químicas, histológicas, e microbiológicas, tornam-se necessárias.
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Nussbaum, Marcy Lauren. "Meta-Analysis of Open vs Closed Surgery of Mandibular Condyle Fractures." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1397.
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A review of the literature reveals a difference of opinion regarding whether open or closed reduction of condylar fractures produces the best results. It would be beneficial to critically analyze past studies that have directly compared the two methods in an attempt to answer this question. A Medline search for articles using the key words 'mandibular condyle fractures' and 'mandibular condyle fractures surgery' was performed. The articles chosen for the meta-analysis contained data on at least one of the following: postoperative maximum mouth opening, lateral excursion, protrusion, deviation on opening, asymmetry, and joint pain or muscle pain. Several common statistical methods were used to test for differences between open and closed surgery, including the weighted average method for fixed and random effects as well as the Mantel-Haenszel method for fixed effects. Some of the outcome variables were found to be statistically significant but were interpreted with caution because of the poor quality of the studies assessed. There is a need for more standardized data collection as well as patient randomization to treatment groups.
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Loftin, Craig R. "An Examination of Open- and Closed-Economic Corxtitions in Operant Research." DigitalCommons@USU, 1989. https://digitalcommons.usu.edu/etd/5997.
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The effect of economic condition on the relation between responding and overall rate of reinforcement has been an area of recent interest in operant research. The present research was conducted to determine whether the manipulation of the economic condition, by the systematic manipulation of the provision of substitute food, has an effect on this relation and whether open- and closed-economies represent two opposing alternatives or two parametric extremes along- a continuum. The results of two experiments conducted with pigeons using variable-interval and fixed-ratio schedules of reinforcement suggest that the manipulation of economic condition has a controlling effect on the relation between responding and overall rate of reinforcement, that open- and closed- economies are likely to represent points along- a continuum rather than all-or-none conditions, and that the differences in the response-to- reinforcement relation between open- and closed-economies are likely due to an interaction of incentive and regulatory effects. Additionally, specific methodological considerations for further research in this area are suggested.
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Gangapuram, Amit Jamadagni [Verfasser]. "Novel approaches to topological order involving open boundaries in closed and open quantum systems / Amit Jamadagni Gangapuram." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2021. http://d-nb.info/1228533466/34.
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Barrett, Leslie Estelle. "The Effect of Workspace Layout on Individual Perceptions of Creativity Across Generational Cohorts." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/3020.
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Organizations strategically design the physical work environment to enhance employees' creativity. Understanding the impact of workspace layout on individual perceptions of creativity across generational cohorts can be vital to sustaining organizational competitiveness. Researchers have theorized that workspace layout affects employees' perceptions of creativity; however, few studies have looked at the effect of generational cohort on this relationship. A quantitative study was conducted to examine the effect of workspace layout on individual perceptions of creativity across generational cohorts. A sample of 162 participants completed an online demographics questionnaire as well as aKEYS, a modified version of the KEYS to Creativity and Innovation instrument. An ANOVA was used to determine whether generational cohort and workspace layouts affected the participants' individual perceptions of creativity. Results did not support the theory that workspace layout and generational cohort affected individual perceptions of creativity. However, these nonsignificant results can be used strategically by organizations to design physical workspaces that foster individual perceptions of creativity in order to attract and retain a diverse workforce by accommodating employees equally rather than on generational cohort membership. Social change implications are that the results can provide organizations with an understanding of ways in which they can effectively treat and meet the needs of the workforce as a whole, rather than develop strategies based on generational cohort membership.
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Bessems, Petrus Johannes Maria Joannes. "The cryosurgical open-cone-spray method." [Maastricht : Maastricht : Rijksuniversiteit Limburg] ; University Library, Maastricht University [Host], 1989. http://arno.unimaas.nl/show.cgi?fid=5517.
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Latifi, Majid. "Using natural language processing for question answering in closed and open domains." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/586063.
Full textAbstract:
With regard to the growth in the amount of social, environmental, and biomedical information available digitally, there is a growing need for Question Answering (QA) systems that can empower users to master this new wealth of information. Despite recent progress in QA, the quality of interpretation and extraction of the desired answer is not adequate. We believe that striving for higher accuracy in QA systems is subject to on-going research, i.e., it is better to have no answer is better than wrong answers. However, there are diverse queries, which the state of the art QA systems cannot interpret and answer properly.
The problem of interpreting a question in a way that could preserve its syntactic-semantic structure is considered as one of the most important challenges in this area. In this work we focus on the problems of semantic-based QA systems and analyzing the effectiveness of NLP techniques, query mapping, and answer inferencing both in closed (first scenario) and open (second scenario) domains. For this purpose, the architecture of Semantic-based closed and open domain Question Answering System (hereafter “ScoQAS”) over ontology resources is presented with two different prototyping: Ontology-based closed domain and an open domain under Linked Open Data (LOD) resource.
The ScoQAS is based on NLP techniques combining semantic-based structure-feature patterns for question classification and creating a question syntactic-semantic information structure (QSiS). The QSiS provides an actual potential by building constraints to formulate the related terms on syntactic-semantic aspects and generating a question graph (QGraph) which facilitates making inference for getting a precise answer in the closed domain. In addition, our approach provides a convenient method to map the formulated comprehensive information into SPARQL query template to crawl in the LOD resources in the open domain.
The main contributions of this dissertation are as follows:
1. Developing ScoQAS architecture integrated with common and specific components compatible with closed and open domain ontologies.
2. Analysing user’s question and building a question syntactic-semantic information structure (QSiS), which is constituted by several processes of the methodology: question classification, Expected Answer Type (EAT) determination, and generated constraints.
3. Presenting an empirical semantic-based structure-feature pattern for question classification and generalizing heuristic constraints to formulate the relations between the features in the recognized pattern in terms of syntactical and semantical.
4. Developing a syntactic-semantic QGraph for representing core components of the question.
5. Presenting an empirical graph-based answer inference in the closed domain.
In a nutshell, a semantic-based QA system is presented which provides some experimental results over the closed and open domains. The efficiency of the ScoQAS is evaluated using measures such as precision, recall, and F-measure on LOD challenges in the open domain. We focus on quantitative evaluation in the closed domain scenario. Due to the lack of predefined benchmark(s) in the first scenario, we define measures that demonstrate the actual complexity of the problem and the actual efficiency of the solutions. The results of the analysis corroborate the performance and effectiveness of our approach to achieve a reasonable accuracy.<br>Con respecto al crecimiento en la cantidad de información social, ambiental y biomédica disponible digitalmente, existe una creciente necesidad de sistemas de la búsqueda de la respuesta (QA) que puedan ofrecer a los usuarios la gestión de esta nueva cantidad de información. A pesar del progreso reciente en QA, la calidad de interpretación y extracción de la respuesta deseada no es la adecuada. Creemos que trabajar para lograr una mayor precisión en los sistemas de QA es todavía un campo de investigación abierto. Es decir, es mejor no tener respuestas que tener respuestas incorrectas. Sin embargo, existen diversas consultas que los sistemas de QA en el estado del arte no pueden interpretar ni responder adecuadamente. El problema de interpretar una pregunta de una manera que podría preservar su estructura sintáctica-semántica es considerado como uno de los desafíos más importantes en esta área. En este trabajo nos centramos en los problemas de los sistemas de QA basados en semántica y en el análisis de la efectividad de las técnicas de PNL, y la aplicación de consultas e inferencia respuesta tanto en dominios cerrados (primer escenario) como abiertos (segundo escenario). Para este propósito, la arquitectura del sistema de búsqueda de respuestas en dominios cerrados y abiertos basado en semántica (en adelante "ScoQAS") sobre ontologías se presenta con dos prototipos diferentes: en dominio cerrado basado en el uso de ontologías y un dominio abierto dirigido a repositorios de Linked Open Data (LOD). El ScoQAS se basa en técnicas de PNL que combinan patrones de características de estructura semánticas para la clasificación de preguntas y la creación de una estructura de información sintáctico-semántica de preguntas (QSiS). El QSiS proporciona una manera la construcción de restricciones para formular los términos relacionados en aspectos sintáctico-semánticos y generar un grafo de preguntas (QGraph) el cual facilita derivar inferencias para obtener una respuesta precisa en el dominio cerrado. Además, nuestro enfoque proporciona un método adecuado para aplicar la información integral formulada en la plantilla de consulta SPARQL para navegar en los recursos LOD en el dominio abierto. Las principales contribuciones de este trabajo son los siguientes: 1. El desarrollo de la arquitectura ScoQAS integrada con componentes comunes y específicos compatibles con ontologías de dominio cerrado y abierto. 2. El análisis de la pregunta del usuario y la construcción de una estructura de información sintáctico-semántica de las preguntas (QSiS), que está constituida por varios procesos de la metodología: clasificación de preguntas, determinación del Tipo de Respuesta Esperada (EAT) y las restricciones generadas. 3. La presentación de un patrón empírico basado en la estructura semántica para clasificar las preguntas y generalizar las restricciones heurísticas para formular las relaciones entre las características en el patrón reconocido en términos sintácticos y semánticos. 4. El desarrollo de un QGraph sintáctico-semántico para representar los componentes centrales de la pregunta. 5. La presentación de la respuesta inferida a partir de un grafo empírico en el dominio cerrado. En pocas palabras, se presenta un sistema semántico de QA que proporciona algunos resultados experimentales sobre los dominios cerrados y abiertos. La eficiencia del ScoQAS se evalúa utilizando medidas tales como una precisión, cobertura y la medida-F en desafíos LOD para el dominio abierto. Para el dominio cerrado, nos centramos en la evaluación cuantitativa; su precisión se analiza en una ontología empresarial. La falta de un banco la pruebas predefinidas es uno de los principales desafíos de la evaluación en el primer escenario. Por lo tanto, definimos medidas que demuestran la complejidad real del problema y la eficiencia real de las soluciones. Los resultados del análisis corroboran el rendimiento