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1
Pratt, Brian Hogan. "Analysis and Mitigation of SEU-induced Noise in FPGA-based DSP Systems." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2482.
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This dissertation studies the effects of radiation-induced single-event upsets (SEUs) on digital signal processing (DSP) systems designed for field-programmable gate arrays (FPGAs). It presents a novel method for evaluating the effects of radiation on DSP and digital communication systems. By using an application-specific measurement of performance in the presence of SEUs, this dissertation demonstrates that only 5-15% of SEUs affecting a communications receiver (i.e. 5-15% of sensitive SEUs) cause critical performance loss. It also reports that the most critical SEUs are those that affect the clock, global reset, and most significant bits (MSBs) of computation. This dissertation also demonstrates reduced-precision redundancy (RPR) as an effective and efficient alternative to the popular triple modular redundancy (TMR) for FPGA-based communications systems. Fault injection experiments show that RPR can improve the failure rate of a communications system by over 20 times over the unmitigated system at a cost less than half that of TMR by focusing on the critical SEUs. This dissertation contrasts the cost and performance of three different variations of RPR, one of which is a novel variation developed here, and concludes that the variation referred to as "Threshold RPR" is superior to the others for FPGA systems. Finally, this dissertation presents several methods for applying Threshold RPR to a system with the goal of reducing mitigation cost and increasing the system performance in the presence of SEUs. Additional fault injection experiments show that optimizing the application of RPR can result in a decrease in critical SEUs by as much 65% at no additional hardware cost.
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Thurlow, Corbin Alma. "TURTLE: A Fault Injection Platform for SRAM-Based FPGAs." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9025.
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SRAM-Based FPGAs provide valuable computation resources and reconfigurability; however, FPGA designs can fail during operation due to ionizing radiation. As an SRAM-based device, these FPGAs store operation-critical information in configuration RAM, or CRAM. Testing, through radiation tests, can be performed to prove the effectiveness of SEU mitigation techniques by comparing the SEU sensitivity of an FPGA design with and without the mitigation techniques applied. However, radiation testing is expensive and time-consuming. Another method for SEU sensitivity testing is through fault injection. This work describes a low-cost fault injection platform for evaluating the SEU sensitivity of an SRAM-based FPGA design by emulating faults in the device CRAM through partial reconfiguration. This fault injection platform, called the TURTLE, is designed to gather statistically significant amounts of fault injection data to test and validate SEU mitigation techniques for SRAM-based FPGAs. Across multiple fault injection campaigns, the TURTLE platform was used to inject more than 600 million faults to test SEU mitigation techniques, estimate design SEU sensitivity, and validate radiation test data through fault injection.
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Howes, William A. "On-Orbit FPGA SEU Mitigation and Measurement Experiments on the Cibola Flight Experiment Satellite." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2474.
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This work presents on-orbit experiments conducted to validate SEU mitigation and detection techniques on FPGA devices and to measure SEU rates in FPGAs and SDRAM. These experiments were designed for the Cibola Flight Experiment Satellite (CFESat), which is an operational technology pathfinder satellite built around 9 Xilinx Virtex FPGAs and developed at Los Alamos National Laboratory. The on-orbit validation experiments described in this work have operated for over four thousand FPGA device days and have validated a variety of SEU mitigation and detection techniques including triple modular redundancy, duplication with compare, reduced precision redundancy, and SDRAM and FPGA block memory scrubbing. Regional SEU rates and the change in CFE's SEU rate over time show the measurable, expected effects of the South Atlantic Anomaly and the cycle of solar activity on CFE's SEU rates. The results of the on-orbit experiments developed for this work demonstrate that FPGA devices can be used to provide reliable, high-performance processing to space applications when proper SEU mitigation strategies are applied to the designs implemented on the FPGAs.
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Amorim, Rafael Ponce de Leon. "Análise da magnitude da influência climática de um remanescente de mata atlântica sobre o seu entorno urbanizado em clima quente-úmido." Universidade Federal da Paraíba, 2011. http://tede.biblioteca.ufpb.br:8080/handle/tede/5456.
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Previous issue date: 2011-09-26Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The urban spaces environmental quality is determined by the interaction between the natural elements and the man-made changes to adapt the environment to their physical, social and economic needs. In this context, is inserted the urban climate, result of the dialogic relationship between the morphology of the city, the human activities and the various local and global climate factors. The climate change, characteristic of urban space, causes several damages to most cities by increasing the rigors of local climate. In this sense, the study of urban space, in particular, the research about urban climatology, become fundamental to the search for environmental quality, as well as to achieve the energy efficiency in urban areas. In the city, the use of vegetation is an important strategy for mitigation of the local climate, however, is still unknown the potential of this contribution, requiring studies to evaluate the best ways of its application, in accordance with the morphology of the green space and urban space and the local climatic characteristics. The present study analyzed the extent and the magnitude of the influence of the Buraquinho s Forest, in João Pessoa/ PB, in the climatic characteristics of their surroundings by monitoring the temperature and the air s humidity in winter and summer periods, arranged in three transects in downwind of the forest, total of thirteen points of data collection, one of them located in forest interior. It was observed that among the points considered, in the summer, the averages air temperatures were in general 3°C higher than the winter and the relative humidity 15% lower. The temperature differences between points with higher and lower temperatures were similar in both periods, it was observed the main difference at 13h: 3° C in the winter and 2,8 °C in the summer. It was also discovered that the lowest temperatures were obtained in points located on the edge of the forest, whereas the higher temperatures were found in the farthest points, however, it wasn t possible to identify a linear tendency of temperature increase associated to the increased distance from the forest.
A qualidade ambiental do espaço urbano é determinada pela interação entre os elementos naturais e as transformações artificiais produzidas pelo homem na adaptação do meio às suas necessidades físicas, sociais e econômicas. Neste contexto, insere-se o clima urbano, fruto da relação dialógica entre a morfologia da cidade, as atividades humanas e os diversos fatores climáticos locais e globais. Por sua vez, a alteração climática no espaço urbano ocasiona diversos malefícios para grande parte das cidades ao intensificar os rigores climáticos locais. Neste sentido, o estudo do espaço urbano e, em especial, as pesquisas sobre climatologia urbana, tornam-se fundamentais para a busca da qualidade ambiental, assim como para o alcance da eficiência energética urbana. Na cidade, o uso de vegetação configura-se em uma importante estratégia para amenização climática local, porém, ainda é desconhecido o potencial dessa contribuição, necessitando-se de estudos que avaliem as melhores formas de sua aplicação, de acordo com a morfologia do espaço verde e do espaço urbano e as características climáticas locais. O presente estudo analisou o alcance e magnitude da influência da Mata do Buraquinho, em João Pessoa/ PB, nas características climáticas do seu entorno ao monitorar a temperatura e umidade do ar nos períodos de inverno e verão, em três transectos dispostos a sotavento da mata, totalizando treze pontos de coleta, sendo um deles localizado em seu interior. Observou-se que entre os pontos analisados, no período de verão, as temperaturas médias do ar foram em geral 3ºC superiores as de inverno e a umidade relativa do ar 15% inferior. As diferenças de temperatura entre pontos com maior e menor temperatura foram semelhantes nos dois períodos, observando-se a maior divergência às 13h, sendo 3°C no inverno e 2,8°C no verão. Constatou-se também, que as menores temperaturas foram obtidas nos pontos localizados na borda da mata, enquanto as maiores temperaturas foram encontradas nos pontos mais afastados, porém não foi possível identificar uma tendência linear de aumento de temperatura relacionada ao aumento do distanciamento da mata.
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Lisboa, Mauricio Santos. "A Exploração do minério de vanádio no município de Maracás/BA: os impactos socioambientais da mineração e seu beneficiamento no povoado de Água Branca." Universidade Catolica de Salvador, 2016. http://hdl.handle.net/123456730/323.
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A EXPLORACAO DO MINERIO DE VANADIO NO MUNICIPIO DE MARACASBA OS IMPACTOS SOCIOAMBIENTAIS DA MINERACAO E SEU BENEFICIAMENTO NO POVOADO DE AGUA BRANCA .pdf: 2704322 bytes, checksum: 875475fc58ecd34d9cf8c97697259a59 (MD5)Approved for entry into archive by Maria Emília Carvalho Ribeiro (maria.ribeiro@ucsal.br) on 2017-03-02T15:48:32Z (GMT) No. of bitstreams: 1 A EXPLORACAO DO MINERIO DE VANADIO NO MUNICIPIO DE MARACASBA OS IMPACTOS SOCIOAMBIENTAIS DA MINERACAO E SEU BENEFICIAMENTO NO POVOADO DE AGUA BRANCA .pdf: 2704322 bytes, checksum: 875475fc58ecd34d9cf8c97697259a59 (MD5)
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O objetivo da presente dissertação consiste em avaliar se a Mineradora Vanádio Maracás, empresa que vem conduzindo a exploração do minério de Vanádio no Município de Maracás/BA, está comprometida com as medidas mitigadoras previstas no EIA/RIMA, realizado como condição para o licenciamento. Visa também verificar se os moradores do povoado de Água Branca, onde ocorreram os impactos socioambientais, têm consciência dos seus direitos, tais como participar de Audiências Públicas para discutir a respeito do processo de licenciamento ambiental e acompanhar a implantação das medidas mitigadoras propostas pelo Empreendimento no EIA/RIMA, avaliando se, de fato, ocorreram impactos positivos quanto à preservação dos cursos d’água, preservação da paisagem cênica, manutenção da flora e da fauna na região, controle sobre poluição sonora e disposição de rejeitos entre outros. No presente estudo, a abordagem qualitativa permitirá ao pesquisador focar na interpretação de valores e significados atribuídos à percepção dos entrevistados sobre as repercussões no meio socioambiental da exploração do vanádio. A população entrevistada constituiu-se de moradores do Povoado de Água Branca, com idade entre 18 e 60 anos ou mais.
The purpose of this thesis is to analyze whether the Maracás Vanadium Mining, a company that has been exploring the Vanadium ore in the municipality of Maracás/BA, is committed to the mitigation measures provided in the EIA/RIMA, performed as a licensing condition. It also aims to verify if the White Water villagers, where social and environmental impacts occurred, are aware of their rights, such as to participate in public hearings in order to discuss about the environmental licensing process and to keep up with the implementation of mitigation measures proposed by the enterprise in the EIA/RIMA, analyzing whether, in fact, positive impacts occurred on the waterways conservation, scenic landscape preservation, flora and fauna maintenance in the region, noise pollution control and tailings arrangement, among others. In this study, the qualitative approach will allow the researcher to focus yourself on the interpretation of values and meanings attributed to the respondents perception about the social and environmental impacts of the vanadium exploration. The survey population consisted of White Water villagers, aged between 18 and 60 years or more.
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Keller, Andrew Mark. "Using On-Chip Error Detection to Estimate FPGA Design Sensitivity to Configuration Upsets." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6302.
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SRAM-based FPGAs provide valuable computation resources and reconfigurability; however, ionizing radiation can cause designs operating on these devices to fail. The sensitivity of an FPGA design to configuration upsets, or its SEU sensitivity, is an indication of a design's failure rate. SEU mitigation techniques can reduce the SEU sensitivity of FPGA designs in harsh radiation environments. The reliability benefits of these techniques must be determined before they can be used in mission-critical applications and can be determined by comparing the SEU sensitivity of an FPGA design with and without these techniques applied to it. Many approaches can be taken to evaluate the SEU sensitivity of an FPGA design. This work describes a low-cost easier-to-implement approach for evaluating the SEU sensitivity of an FPGA design. This approach uses additional logic resources on the same FPGA as the design under test to determine when the design has failed, or deviated from its specified behavior. Three SEU mitigation techniques were evaluated using this approach: triple modular redundancy (TMR), configuration scrubbing, and user-memory scrubbing. Significant reduction in SEU sensitivity is demonstrated through fault injection and radiation testing. Two LEON3 processors operating in lockstep are compared against each other using on-chip error detection logic on the same FPGA. The design SEU sensitivity is reduced by 27x when TMR and configuration scrubbing are applied, and by approximately 50x when TMR, configuration scrubbing, and user-memory scrubbing are applied together. Using this approach, an SEU sensitivity comparison is made of designs implemented on both an Altera Stratix V FPGA and a Xilinx Kintex 7 FPGA. Several instances of a finite state machine are compared against each other and a set of golden output vectors, all on the same FPGA. Instances of an AES cryptography core are chained together and the output of two chains are compared using on-chip error detection. Fault injection and neutron radiation testing reveal several similarities between the two FPGA architectures. SEU mitigation techniques reduce the SEU sensitivity of the two designs between 4x and 728x. Protecting on-chip functional error detection logic with TMR and duplication with compare (DWC) is compared. Fault injection results suggest that it is more favorable to protect on-chip functional error detection logic with DWC than it is to protect it with TMR for error detection.
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Stoddard, Aaron Gerald. "Configuration Scrubbing Architectures for High-Reliability FPGA Systems." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5704.
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Field Programmable Gate Arrays (FPGAs) are being used more frequently in space applications because of their reconfigurability and intensive processing capabilities. FPGAs in environments like space are susceptible to ionizing radiation which can cause Single Event Upsets (SEUs) in the FPGA's configuration memory. These upsets may cause the programmed user design on the FPGA to deviate from its normal behavior. Space missions cannot afford to allow important data processing applications to become corrupted due to these radiation upsets.Configuration scrubbing is an upset mitigation technique that detects and corrects upsets in an FPGA's configuration memory. Configuration scrubbing periodically monitors an FPGA's configuration memory utilizing mechanisms such as Error Correction Codes (ECCs), Cyclic Redundancy Checks (CRCs), a protected golden file, and partial reconfiguration to detect and correct upset memory bits. This work presents improved Xilinx 7-Series configuration scrubbing architectures that achieve minimal hardware footprints, competitive performance metrics, and robust detection and correction capabilities. The two principal scrubbing architectures presented in this work are the readback and hybrid scrubbers which detect and correct Single Bit Upsets (SBUs) and Multi-Bit Upsets (MBUs). Harnessing the performance advantages granted by the 7-Series internal Readback CRC scan, a hybrid scrubber built in software for the Zynq XZC07020 FPGA has been measured to correct SBUs in 8.024 ms, even-numbered MBUs in 13.38 ms, and odd-numbered MBUs in 21.40 ms. It can also perform a full readback scrub of the entire device in under two seconds. These scrubbing architectures were validated in radiation beam tests, where one of the architectures corrected MBUs as large as sixteen bits in a single frame.
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Torrens, Caldentey Gabriel. "Estudio de eventos transitorios inducidos por radiación en memorias SRAM nanométricas." Doctoral thesis, Universitat de les Illes Balears, 2012. http://hdl.handle.net/10803/97291.
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Los efectos de la radiación en circuitos electrónicos se conocen desde los comienzos de la carrera espacial en los años 60, pues fuera de la atmósfera terrestre se está expuesto a niveles más altos de radiación que en la superficie. Sin embargo, el escalado de la tecnología electrónica ha conllevado un aumento de su susceptibilidad a la radiación, que puede desembocar en errores de funcionamiento incluso a nivel de tierra. Esta tesis estudia un efecto de la radiación, en memorias SRAM (Static Random Access Memory), denominado evento transitorio, que se caracteriza por corromper los datos almacenados en la memoria sin dañarla permanentemente. Se estudian por simulación diversas técnicas para diseñar memorias más robustas frente a eventos transitorios. Además, se ha diseñado y fabricado un prototipo de SRAM que incorpora algunas de estas técnicas. Finalmente, se ha validado experimentalmente su eficacia mediante la irradiación controlada del circuitoRadiation effects in electronic circuits are known since the beginning of the space race in the 1960s, because out of the terrestrial atmosphere, radiation exposure level is higher than on the surface. However, electronic technology scaling has led to an increase in radiation susceptibility that can result in operation errors even at ground level. This thesis deals with a radiation effect, in SRAMs (Static Random Access Memory), named transient event, which is characterized by corrupting data stored in the memory without causing any permanent damage to it. Several techniques to design more robust memories against radiation effects are studied by simulation. In addition, an SRAM prototype, including some of these techniques, has been designed and manufactured. Finally, the effectiveness of these techniques has been experimentally validated through controlled irradiation of the circuit.
Els efectes de la radiació en circuits electrònics es coneixen des dels inicis de la carrera espacial als anys 60, ja que fora de l’atmosfera terrestre s’està exposat a nivells més alts de radiació que a la superfície. No obstant això, l’escalat de la tecnologia electrònica ha comportat un augment de la susceptibilitat a la radiació, que pot desembocar en errors de funcionament fins i tot a nivell de terra. Aquesta tesi estudia un efecte de la radiació, en memòries SRAM (Static Random Access Memory), anomenat event transitori, que es caracteritza per corrompre les dades emmagatzemades a la memòria sense danyar-la permanentment. S’estudien per simulació diverses tècniques per dissenyar memòries més robustes en front a events transitoris. A més, s’ha dissenyat i fabricat un prototipus d’SRAM que incorpora alguna d’aquestes tècniques. Finalment, s’ha validat experimentalment la seva eficàcia mitjançant la irradiació controlada del circuit.
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Smart, Jennifer. "Strategies of sea-level rise mitigation for breeding redshank." Thesis, University of East Anglia, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426991.
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Hullinger, Weston Jay. "Mitigation of Sea Ice Contamination in QuikSCAT Wind Retrieval." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3412.
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Satellite borne radar scatterometers provide frequent estimates of near surface wind vectors over the Earth's oceans. However in the polar oceans, the presence of sea ice in or near the measurement footprint can adversely a ect scatterometer measurements resulting in inaccurate wind estimates. Currently, such ice contamination is mitigated by discarding measurements within 50 km of detected sea ice. This approach is imperfect and causes loss of coverage. This thesis presents a new algorithm which detects ice-contaminated measurements based on a metric called the Ice Contribution Ratio (ICR) which measures the spatial ice contribution for each measurement. The ICR calculation is made for each measurement using a spatial ice probability map which is determined using Bayesian probability theory. Determined by simulation, the ICR processing thresholds the ICR for each measurement depending on local wind, ice backscatter, and cross-track location. ICR processing retrieves winds at a distance of 22.5 km from the ice edge on average, while ensuring wind accuracy. Retrieved wind distributions using ICR processing more closely resembles uncontaminated wind distributions than winds retrieved using previous methods. The algorithm is applied to QuikSCAT in this thesis but could be applied to other scatterometers such as the Oceansat-2 scatterometer.
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Kotsifas, Dionysios. "Network-based mitigation of illegal immigration in Aegean Sea (Greece)." Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/5218.
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Approved for public release; distribution is unlimitedIllegal immigration is a serious concern of countries neighboring devastated parts of the modern world. Illegal migrants dreaming of a new life follow perilous routes, cooperating with smuggling networks. For a significant portion, their dream never comes true. Besides, smugglers are also responsible for other illegal activities, such as drugs and weapons trafficking. Greece not only faces the problem of absorbing these immigrants from Africa and Greater Middle East countries, but it also has no chance to filter those migrants involved in dark networks. The Hellenic Coast Guard, lacking timely information on suspect vessels moving towards its territorial waters in the Eastern Aegean Sea, strives to be in the right place at the right time. The need for an ever-present adaptive networking system able to provide reliable communication and sensor data to and from the areas of responsibility is more profound than ever. This thesis examines the feasibility and constraints of applying modern networking technology, already successfully tested by NPS CENETIX TNT/test bed, on Aegean Sea islands as a concept of providing information to the Hellenic Coast Guard to enhance situational awareness and decision-making capability and thus increase overall effectiveness and efficiency while carrying out missions in that area.
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Perkins, Andrew Brian. "Effects of Professional Mitigation in Cases Involving Illegal Sexual Behavior." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/577189.
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Mitigating evidence is evidence that is presented during the sentencing phase of a trial and is meant to argue for leniency in sentencing. A new form of psycho-legal professional, called a mitigation specialist, is being relied upon more often to assemble the diverse array of psychosocial factors into coherent arguments for less severe sentences. Unfortunately, there is a lack of empirical evidence upon which such professionals can base their work. This is of particular concern in the context of sex offenses—where strong attitudes may overwhelm legal instruction. In collaboration with the Office of the Pima County Public Defender, the current investigation utilized 209 cases; half involving sex offenses, half involving violent non-sexual offenses, and half utilizing professional mitigation, half not utilizing professional mitigation, to better elucidate the effects of professional mitigation reports on sentences in cases involving sexual and violent nonsexual crime. Results revealed that the effectiveness of mitigation reports was heavily moderated by case type. While mitigating evidence was effective in reducing sentence length for violent nonsexual offenses, it had the opposite effect in the cases involving sex offenses. Psychological reports, however were effective in reducing sentence lengths for cases involving sex offenses. Individual mitigating factors and lexical characteristics (examined through Linguistic Inquiry and Word Count software) did not show any consistent relationship with sentence length, suggesting that the effect of the mitigation reports as a whole cannot necessarily be discerned from its parts. Limitations, future directions, and possible implications for the practice of mitigation specialists are explored.
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Olofsson, Martin. "Microalgae - future bioresource of the sea?" Doctoral thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-46512.
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Unicellular microalgae are a renewable bioresource that can meet the challenge forfood and energy in a growing world population. Using sunlight, CO2, nutrients,and water, algal cells produce biomass in the form of sugars, proteins and oils, allof which carry commercial value as food, feed and bioenergy. Flue gas CO2 andwastewater nutrients are inexpensive sources of carbon and fertilizers. Microalgaecan mitigate CO2 emissions and reduce nutrients from waste streams whileproducing valuable biomass.My focus was on some of the challenging aspects of cultivating microalgae ascrop: the response of biomass production and quality to seasonality, nutrients andbiological interactions. Approach spans from laboratory experiments to large-scaleoutdoor cultivation, using single microalgal strains and natural communities insouthern (Portugal) and northern (Sweden) Europe.Half of the seasonal variation in algal oil content was due to changes in light andtemperature in outdoor large-scale cultures of a commercial strain (Nannochloropsisoculata). Seasonal changes also influence algal oil composition with more neutrallipids stored in cells during high light and temperature. Nitrogen (N) stress usuallyenhances lipid storage but suppresses biomass production. Our manipulationshowed that N stress produced more lipids while retaining biomass. Thus,projecting annual biomass and oil yields requires accounting for both seasonalchanges and N stress to optimize lipid production in commercial applications.Baltic Sea microalgae proved to be a potential biological solution to reduce CO2emissions from cement flue gas with valuable biomass production. A multi-speciescultivation approach rather than single-species revealed that natural or constructedcommunities of microalgae can produce equivalent biomass quality. Diversecommunities of microalgae can offer resilience and stability due to more efficientresource utilization with less risk of contamination, less work and cost for culturemaintenance.Stable algal biomass production (annual basis) was achieved in outdoor pilot-scale(1600 L) cultivation of Baltic Sea natural communities using cement flue gas as aCO2 source. Results indicate favorable algal oil content at northern Europeanlatitudes compared to southern European latitudes.My thesis establishes the potential of cultivating microalgae as a bioresource inScandinavia, and using a community approach may be one step towardssustainable algal technology.
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Dinovitzer, Ronit. "Sentencing sexual assault : a study of mitigation and aggravation." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22580.
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In an effort to establish a clearer understanding of the sentencing of sexual assault offenders, this study analyzes data generated from a content analysis of sexual assault cases, using feminist theory as a backdrop for the analysis. The sample consists of ninety-seven sexual assault cases from across Canada for the period of August 15, 1992 through August 15, 1993. Using a statistical analysis, the data were analyzed for evidence of whether certain factors aggravated or mitigated sentence length. The findings indicate that factors not affecting sentence length include breach of trust, sex of the judge, sex of the complainant, plea and show of remorse. Factors that work to mitigate sentence length include the youth or old age of an offender. Finally, variables that, when present, aggravate an offender's sentence length are prior offences, force, sexual intercourse and psychiatric considerations. These findings indicate that while there has been some response to feminist concerns regarding criminal justice processing of sexual assault, some of the myths that have been traditionally associated with its victims and offenders are still influencing the judiciary.
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Wathanaprida, Somsak. "Tsunami impacts and mitigation plans for the Khoa Lak (Andaman Sea), coastal areas of Thailand." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/37162/.
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To build a tsunami-resilient coastal community it is fundamental to understand the characteristics of past tsunami patterns and likely impact of possible future events. The MOST model (Method of Splitting Tsunami) and ComMIT (Community Model Interface for Tsunami) were used to model patterns of water levels, wave speed and direction, and inundation distances resulting from the 2004 Indian Ocean tsunami on the Khao Lak coast of Thailand. The model of the 2004 tsunami was calibrated against estimates of water depths made along the coast in early 2005; an M, = 9.3 earthquake in the model was found to best match observations. The model was verified against a variety of other evidence, including digital photographs and video clips taken on the day of the tsunami, mainly from two sites along the Khao Lak coast at Nang Thong and Bang Niang beaches, together with aerial surveys and a tide-gauge record. The timing and extent of water recession prior to the arrival of the first wave, the heights and number of the subsequent waves, and the inundation distances corresponded well providing confidence in the application of the MOST model to this coastal region. Historical evidence suggest that tsunami of the magnitude of 2004 are rare (200-700 y) so for mitigation planning in the Khao Lak area a smaller tsunami genic-earthquake (M; =8.9) was chosen (l00-500 y). Sensitivity to the choice of M, was also considered. The tsunami from such an event is similar in its character to the 2004 event, less extreme but still highly destructive, reaching the Khao Lak coast in ~ 2 h 15 min, and preceded by receding water levels. The first wave (5.0-6.5 m high) arrives 2h 25 min after the earthquake travelling at 6-8 mls at the coastline.
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Tutko, Benjamin Thomas. "Analysis of In-Lieu Fee Programs in providing Wetland and Stream Compensatory Mitigation." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/79673.
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The nation's Section 404 permitting program, of the Clean Water Act (CWA), represents one of the longest regulatory histories of designing and implementing credit trading programs to satisfy regulatory requirements. The role and the function of in-lieu fee (ILF) programs in supporting this regulatory structure have undergone a substantial change. For the first time in the history of the Sec. 404 program, 33 CFR Part 332 and 40 CFR Part 230, Subpart J (the "2008 mitigation rule" or "rule"), prioritizes the use of off-site mitigation over on-site-mitigation. Additionally, the rule prioritizes advanced, third-party mitigation; especially as achieved through mitigation banks; over any off-site compensatory mitigation provided by ILF programs (33 CFR 332.3(b)(1)). This new regulatory environment favors the use of commercial mitigation bank credits while acknowledging that the limited permittee demand of off-site mitigation credits, in particular areas, justifies the continuing need for ILF programs (Corps and EPA 2008, p.19606,19611). This research examines how regulatory officials use ILF programs under the 2008 mitigation rule, and, it determines the extent to which ILF programs are capable of fulfilling the role envisioned for them under the 2008 mitigation rule. Simulation results indicate that commercial mitigation banks cannot meet risk adjusted returns under limited credit demand conditions. ILF programs offer some additional financial capacity to fill the void in commercial bank coverage; but, this potential is limited in low demand conditions. Furthermore, empirical case studies of a Virginia and Georgia provide evidence that regulatory officials rely on ILF programs to provide off-site compensatory mitigation almost exclusively in the absence of private credit supply, as intended in the 2008 rule. Evidence in Georgia and Virginia also indicate that, in some situations, ILF programs face difficulties in providing mitigation under the constraints of limited demand and more stringent regulatory requirements.Master of Science
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Gresham, Anne Ellen. "Identifying and Mitigating Domestic Minor Sex Trafficking in an Urban Community." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/280.
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Human trafficking, domestic minor sex trafficking (DMST), and commercial sexual exploitation of children (CSEC) are complex and multifaceted occurrences in the United States. As the numbers of youth ensnared in sexually exploitive situations increase, organizations and communities are called upon to address the ramifications of this abuse; little research was located, however, that examined collaborative networks and partnerships that address victim identification and mitigation of DMST and CSEC. The purpose of this qualitative single case study was to determine whether strategic partnerships existed within the community under investigation. The theoretical framework was environmental theory, as first described by Florence Nightingale; the conceptual framework was centered on collaborative networks. Research questions focused on victim identification and organizational strategies for collaboration and mitigation of sex trafficking. The research population was composed of 8 individuals working in organizations in a metropolitan area on the West Coast that served victims of DMST and CSEC. Data obtained from interviews were coded, compared, and analyzed for major and emergent themes. Findings indicated that, in the effort to identify victims, these 8 individuals needed to consider all children involved in prostitution as victims and not criminals. Further, their efforts toward mitigation needed to center on widespread education across the broader social spectrum of the issues with DMST and CSEC. These workers identified strategies identified to address DMST and CSEC included the "5 Ps": prevention, protection, prosecution, partnership, and policy. These findings may inform organizations and policy makers about how to make informed decisions about the needs and challenges of addressing sexually exploited youth.
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Ståhle, Johanna, and Linnea Henriksson. "Using Blue Mussels as a Tool for Mitigating Eutrophication in the Baltic Sea." Thesis, Linköpings universitet, Industriell miljöteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-149281.
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Eutrophication is a consequence of excess nutrients in the water which leads to increased algaegrowth, reduced water transparency and hypoxic bottoms. This is the biggest environmental problemfor the Baltic Sea which recently has resulted in stricter legislations and other initiatives to help theBaltic Sea to recover. However, the actions to reduce the nutrient input to the Baltic Sea have so farmainly been land-based. These actions seem to not be enough since the eutrophication continues tobe a problem for the Baltic Sea. Farming blue mussels has shown to have a mitigating effect on theeutrophication and could thus be a complementary action. Blue mussels are filter-feeding specieswhich means that they filter water for food and thus eat phytoplankton and accumulate nutrients atthe same time. When the blue mussels are removed from the sea, so is the nutrients accumulated inthe mussels, resulting in a mitigation of nutrients and thereby the eutrophication. Due to the brackishwater with the low salinity in the Baltic Sea, the blue mussels farmed there do not grow bigger thanaround 3 cm. This means that the mussels are not suitable for human food production and theharvested mussels need to be used for something else, even though the farming itself is anenvironmental action. Three possible mussel products from valorisation of the Baltic Sea blue musselshave been identified; producing mussel meal, biogas or compost.Region Östergötland is involved in a project, Baltic Blue Growth, with the main objective to study howto use mussel farming as an environmental measure and which of the three valorisation options is themost beneficial from an environmental perspective. This study is a part of their investigation to reachtheir goal and will study their mussel farm in St. Anna and the three valorisation options from anenvironmental perspective. The aim of this study is thus to investigate the net nutrient reduction froma mussel farm in the Baltic Sea in combination with the contribution to climate change. This is donefrom a life cycle perspective to include the valorisation of the mussels into the different productsmussel meal, biogas or compost. For this, an existing farm in the archipelago of St. Anna, Östergötland,Sweden is studied. The main results show that there is a nutrient reduction from the mussel farm andthis is not majorly affected regardless of which valorisation option that is chosen. However, the musselfarm does have an impact on climate change and the magnitude of the impact varies for the threevalorisation options. The results of the sensitivity analysis show that the result from the life cycle canbe improved with future improvements of the mussel farm and transportation. The nutrient reductioncan become larger and the impact on the climate change can be reduced. Outside the result from thelife cycle analysis it is discussed that there are other future improvement possibilities in the productionof the mussel products, which would impact the result. The mussel farm and the mussel products alsohave other positive impacts that is not included in the life cycle analysis but discussed in the study,such as increased water transparency, recycling of nutrients and reduction of over fishing. However,the mussel farm could also have negative impacts, such as emissions of microplastics and locallyincreased sedimentation which affect the hypoxia. Those are discussed in this study but the probabilityand possible impact of them are not fully investigated and need further research.
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Mondal, Abrez. "ANALYSIS AND MITIGATION OF FREQUENCY DISTURBANCES IN AN ISLANDED MICROGRID." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492563068162654.
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Courtney, Paige Therese. "Rising Water: Harnessing the Process of Sedimentation for a Flood Resilient Coastal Landscape." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78745.
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This thesis examines the relationships between rising water levels, vulnerable land, and sedimentation within the Chesapeake Bay watershed. Climate induced sea level rise threatens low lying coastal land, especially in regions of continuing subsidence such as the Chesapeake Bay. Alterations to shorelines over time have impacted the ability of coastal landscapes to capture and build up sediment, exposing them to continual erosion. The low lying neighborhood of Belle View along the Potomac River is the focus of the investigation due to its vulnerability to flooding and its cultural and ecological connections to the adjacent landscapes of Dyke Marsh and the George Washington Memorial Parkway. Through careful placement of breakwater infrastructure, sediment will build over time as the water rises, mitigating the effects of coastal flooding in this region. Alterations to the landscapes of the marsh and parkway allow for their cultural and recreational values to be strengthened over time as the landscape adjusts to the rising sea level.Master of Landscape Architecture
Climate change, or the belief that human activity is altering the earth's climate, is projected to increase the occurrence of flood events due to water levels rising over time from glaciers melting. Previously, shorelines have been hardened with levee or seawall infrastructure to creates a barrier between the water and developed land. Hardened shorelines may increase water velocity and reflect wave energy in riverine landscapes, consequentially disturbing natural shorelines. This disturbance leads to the gradual loss of sediment over time and therefore a loss of ground elevation. When landscapes lose elevation, they become more vulnerable to rising water levels and flooding. This relationships between shoreline types, sedimentation, rising water, and vulnerability inspired me to discover and design a threatened landscape that would capture sediment within the river's water column to build elevation over time and protect the adjacent development from rising water. The area encompassing the low lying neighborhood of Belle View, Dyke Marsh, and the George Washington Memorial Parkway along the Potomac River is the focus of the investigation due to its vulnerability to flooding. With a careful understanding of sediment capture infrastructure dynamics, the design introduces breakwaters on the site to allow sediment to build over time as the water rises. This research and design thesis demonstrates a strategy to create landscapes that will evolve over time to mitigate future flooding events and create more resilient landscapes.
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Ali, Syed Saqlain. "Physical-layer cooperative interference mitigation techniques for wireless heterogeneous systems." Doctoral thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/23812.
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Doutoramento em Telecomunicações Departamento de ElectrónicaO tráfego móvel com origem em redes celulares está a aumentar exponencialmente, principalmente devido ao uso de serviços de dados como o vídeo. Uma forma efetiva de lidar com essas exigências é reduzir o tamanho da célula, implementando células pequenas (SCs), ao longo da área de cobertura do atual sistema macro-celular. A implementação de SCs melhora a cobertura de forma significativa. No entanto, como as licenças de espectro adicionais são difíceis e caras de adquirir, espera-se que a macro e as pequenas células possam coexistir sob o mesmo espectro. A coexistência dos dois sistemas resulta em interferências entre eles. Neste contexto, esta tese foca-se no projeto de várias técnicas de mitigação de interferência em redes heterogéneas (HetNets) sob requisitos de coordenação limitados. A primeira parte da tese foca-se no projeto de várias técnicas baseadas no alinhamento de interferência (IA) para o sentido descendente do sistema heterogéneo. Mais especificamente, são propostos esquemas baseados no alinhamento de interferência com diferentes níveis de coordenação intersistema e a restrição de que o desempenho do sistema macro-célula é mantido próximo do caso em que o sistema SCs é desligado. A segunda parte da tese centra-se no projeto conjunto de técnicas baseadas no IA e códigos por bloco no espaço -frequência (SFBCs) para o sentido descendente. Mais especificamente, é apresentado o projeto do esquema de IA com SFBCs orientado para se obter diversidade. A principal motivação para o projeto conjunto do IA com SFBCs, é permitir a coexistência dos dois sistemas, considerando uma pequena troca de informação entre sistemas. As células pequenas apenas precisam de saber que o SFBC é usado pelo sistema macro-celular, não sendo necessária a troca de nenhum canal inter-sistema, contrariamente aos outros esquemas propostos na primeira parte da tese. A parte final da tese apresenta a aplicação do alinhamento de sinal (SA) e codificação de rede física (PNC) para a ligação ascendente do sistema heterogéneo. A principal motivação por detrás do projeto conjunto SA-PNC é aproveitar o alinhamento do sinal e codificação de rede física, para utilizar a interferência como um sinal útil, permitindo que mais utilizadores possam estar ativos simultaneamente. Os resultados numéricos mostram claramente que os métodos propostos fornecem um desempenho próximo do ótimo, com o mínimo de troca de informação entre sistemas.
Mobile tra c in cellular based networks is increasing exponentially, mainly due to the use of data intensive services like video. One e ective way to cope with these demands is to reduce the cell-size by deploying small-cells (SCs) along the coverage area of the current macro-cell system. The deployment of SCs signi cantly improves the coverage. Nevertheless, as additional spectrum licenses are di cult and expensive to acquire, it is expected that the macro and small-cells will coexist under the same spectrum. The coexistence of the two systems results in co-tier/intra-system and crosstier/ inter-system interference. In this context, this thesis focuses on the design of several interference mitigation techniques in order to cancel the interference in heterogeneous networks (HetNets) under limited coordination requirements. The rst part of the thesis focuses on the design of several interference alignment (IA) based techniques for the downlink of HetNets. More specifically, we design IA based schemes under di erent levels of inter-system coordination and the constraint that the performance of macro-cell system is kept close to the case where SC system is switched-o . The second part of the thesis focuses on the joint design of IA and spacefrequency block codes (SFBCs) for the downlink of HetNet. More specifically, the design of diversity-oriented IA scheme with SFBCs is presented. The main motivation for joint IA with SFBCs is to allow the coexistence of two systems under minor inter-system information exchange. The SCs just need to know what SFBC is used by the macro-cell system and no inter-system channels need to be exchanged, contrarily to other schemes proposed in the rst part of the thesis. The nal part of the thesis presents the application of joint signal alignment (SA) and physical network coding (PNC) for the uplink of HetNets. The main motivation behind the joint design of SA-PNC is to take advantage of SA and PNC to utilize the interference as a useful signal that allows the network to achieve high degree of freedom (DoF) by serving more users. The numerical results clearly show that the proposed methods provide close to optimal performance with minor overheads.
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Shen, Andrea Ann. "Evaluation of Wave-Adaptive Modular Vessel Suspension Systems for Improved Dynamics." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23178.
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A study is conducted to test the dynamics of the 33ft Wave-Adaptive Modular Vessel (WAM-V) when outfitted with different suspension systems. Instrumented with an array of sensors, the vessel is tested with two different suspension arrangements to characterize how they affect WAM-V dynamics, and to ultimately select a suspension that is most suitable for the 33ft WAM-V and other vessels that are planned for the future.Optimizing the suspension can reduce the magnitude of accelerations at the payload tray, benefiting both the operator and the payload. Reduced accelerations can significantly improve comfort and risk of injury to the operator, while also lessening the likelihood of any damage to any sensitive cargo onboard. The stock suspension components are characterized through in-house tests conducted at the Center for Vehicle Systems and Safety (CVeSS) at Virginia Tech (VT). Based on the stock characterizations, new suspension components are chosen to better fit the needs of the 33ft WAM-V.
Sea trials are conducted with both suspension systems at the Combatant Craft Division (CCD), a division of the Naval Surface Warfare Center, Carderock Division (NSWCCD), in Norfolk, VA to quantitatively and qualitatively determine the differences between the two suspensions. The 33ft WAM-V is instrumented with a series of accelerometers and potentiometers for measuring accelerations and displacements. The data is analyzed for the sea trials conducted at CCD and the results of the analysis indicate that the suspension selection can significantly affect the transmission of shock and vibrations from the pontoons to the operator or payload tray. Both suspensions are able to mitigate a significant amount of the shocks seen at the pontoons, however, the results do not definitively show which suspension is the better of the two. This is due to the fact that each suspension is not subjected to the exact same wave conditions, and
therefore the resulting suspension dynamics vary. For instance, during a 2-foot wave event, the new suspension attenuates more shock than the stock suspension, 76% versus 71%. However, during a 4-foot wave event, the stock suspension attenuates more shock than the new suspension, 66% versus 60%.
Additionally, the suspension selection can significantly influence the ride height. The stock suspension provides a 70/30 ratio between extension and compression stroke, while the new suspension provides a 50/50 ratio. The more balanced split between the extension and compression strokes allow for better utilizing the total available stroke for the suspension in both directions. This significantly reduces the resulting high-g impacts since the suspension does not frequently bottom out when the vessel is subjected to a large wave.
It is recommended that the results of this study be extended through laboratory dynamic testing that allows for more repeatable dynamic events than sea trials in order to better establish the influence of each suspension parameter on the vessel dynamics. Such tests will also allow for a better understanding of the dynamics of the vessel in response to various inputs at the pontoons, both subjectively (visually) and objectively (through measurements).
Master of Science
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Zilinskaite, Emilija. "Is blue mussel farming a potential mitigation tool to combat eutrophication in the Baltic Sea? A synthesis based on stakeholder interviews." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385792.
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The Baltic Sea is the most polluted sea in the world. Its hydrological conditions and ongoing eutrophication are a high threat for marine biodiversity and ecosystems. Additionally, eutrophication has negative effects on the wellbeing of countries and their societies in the Baltic Sea Region (BSR). Actions to mitigate eutrophication in the Baltic Sea have been implemented through on-land measures in the last 40 years. Although the improvement in the marine environment is notable, it happens very slowly. In order to combat eutrophication, there is a need for a combination of on-land and in-situ measures. In this study, blue mussel farming practices are presented as one of the in-situ measures to combat eutrophication in the Baltic Sea. Blue mussel farming has been implemented in Sweden since the 1980s and has potential to not only mitigate the amounts of nutrients that accumulate in the sea but also brings a circular approach to resource use. In this study, stakeholders from four different sectors that are closely related to blue mussel farming practices and Baltic Sea issues have been interviewed with the aim of making a comprehensive analysis of stakeholder perceptions of blue mussel farming practices in the BSR. Interviewed stakeholders represent four different sectors - academia, entrepreneurs, municipalities and NGOs. A comprehensive analysis of stakeholders’ perceptions on blue mussel farming practises from environmental, social and economic perspective is presented. All interviewed stakeholders are actors in Sweden and represent Swedish perspective on blue mussel farming activities. Potential causes for different perceptions across sectors are discussed.
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Gruwell, Ammon Bradley. "High-Speed Programmable FPGA Configuration Memory Access Using JTAG." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6321.
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Over the past couple of decades Field Programmable Gate Arrays (FPGAs) have become increasingly useful in a variety of domains. This is due to their low cost and flexibility compared to custom ASICs. This increasing interest in FPGAs has driven the need for tools that both qualify and improve the reliability of FPGAs for applications where the reconfigurability of FPGAs makes them vulnerable to radiation upsets such as in aerospace environments. Such tools ideally work with a wide variety of devices, are highly programmable but simple to use, and perform tasks at relatively high speeds. Of the various FPGA configuration interfaces available, the Joint Test Action Group (JTAG) standard for serial communication is the most universally compatible interface due to its use for verifying integrated circuits and testing printed circuit board connectivity. This universality makes it a good interface for tools seeking to access FPGA configuration memory. This thesis introduces a new tool architecture for high-speed, programmable JTAG access to FPGA configuration memory. This tool, called the JTAG Configuration Manager (JCM), is made up of a large C++ software library that runs on an embedded micro-processor coupled with a hardware JTAG controller module implemented in programmable logic. The JCM software library allows for the development of custom JTAG communication of any kind, although this thesis focuses on applications related to FPGA reliability. The JCM hardware controller module allows these software-generated JTAG sequences to be streamed out at very high speeds. Together the software and hardware provide the high-speed and programmability that is important for many JTAG applications.
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Kitchen, Robert Raymond. "Exploration, quantification, and mitigation of systematic error in high-throughput approaches to gene-expression profiling : implications for data reproducibility." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5691.
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Technological and methodological advances in the fields of medical and life-sciences have, over the last 25 years, revolutionised the way in which cellular activity is measured at the molecular level. Three such advances have provided a means of accurately and rapidly quantifying mRNA, from the development of quantitative Polymerase Chain Reaction (qPCR), to DNA microarrays, and second-generation RNA-sequencing (RNA-seq). Despite consistent improvements in measurement precision and sample throughput, the data generated continue to be a ffected by high levels of variability due to the use of biologically distinct experimental subjects, practical restrictions necessitating the use of small sample sizes, and technical noise introduced during frequently complex sample preparation and analysis procedures. A series of experiments were performed during this project to pro le sources of technical noise in each of these three techniques, with the aim of using the information to produce more accurate and more reliable results. The mechanisms for the introduction of confounding noise in these experiments are highly unpredictable. The variance structure of a qPCR experiment, for example, depends on the particular tissue-type and gene under assessment while expression data obtained by microarray can be greatly influenced by the day on which each array was processed and scanned. RNA-seq, on the other hand, produces data that appear very consistent in terms of differences between technical replicates, however there exist large differences when results are compared against those reported by microarray, which require careful interpretation. It is demonstrated in this thesis that by quantifying some of the major sources of noise in an experiment and utilising compensation mechanisms, either pre- or post-hoc, researchers are better equipped to perform experiments that are more robust, more accurate, and more consistent.
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Dragon, Katharina Agnes. "Funding social sector activity in Brazil: a case study analysis of agency risk incidence and mitigation." reponame:Repositório Institucional do FGV, 2012. http://hdl.handle.net/10438/9929.
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Empresas e organizações sociais têm um papel cada vez mais importante no mercado brasileiro. Essas organizações - sejam elas com ou sem fins lucrativos –têm como objetivocausar um profundo e positivo impacto social.Ambas enfrentamtambém o mesmo desafio: financiar as suas operações. Recentemente, dois modelos inovadores de financiamento, o fundo de venture capitalVox Capital e o fundo de empréstimo social SITAWI, entraram no mercado brasileiro para solucionar esse desafio. Este estudo analisa ambos os fundos,associando o problema do financiamento de empresas e organizações sociais às teorias tradicionais de negócio. Mais especificamente, por meio de um estudo de caso,é avaliado se o risco de agência (agency risk) explica as práticas e o designcontratual utilizados pelos fundos. A pesquisa é baseada num estudo de Alemany e Scarlata (2010) sobre a estruturação dos negócios de fundos filantrópicos de capital empreendedor (PhVC, na sigla em inglês) na América do Norte e na Europa. Uma definição chave desse estudo é que organizações sem fins lucrativos, ao contrário daquelas com fins lucrativos, estão sujeitas a uma restrição de distribuição de lucros. Embora Alemany e Scarlata (2010) tivessem descobertoque parceria (stewardship), mais do que o problema de agência (agency problem), explica a estrutura dos negócios dos fundos PhVC, as implicações do presente estudo de caso para o Brasil são diferentes. Os resultados sugerem que o problema de agência,mais do que a parceria,descreve adequadamente os contratos analisados de financiamento. Detectou-seque cláusulas contratuais não foram apenas usadas para mitigar o risco de agênciaresultanteda ausência de uma restrição de distribuição de lucros, mas também para reger as estruturas cooperativas com organizações sem fins lucrativos. No caso de SITAWI, a restrição dos destinatários de fundos de distribuir lucros provou-se uma ferramenta efetiva para alinhar os interesses entre os financiadores e os destinatários dos fundos. Apesar daimplicação da presença de parceria, os contratos do fundo social contiveram cláusulas geralmente usadas para reduzir o risco de agência. No caso de Vox Capital, os destinatários dos fundos eram empresas com fins lucrativos, portanto não sujeitas à restrição de distribuição de lucros. O modelo de negócio de Vox Capital é organizado para impedir qualquer incidência potencial do problema de agência. Ambos os fundos, independentemente da estrutura jurídica dos beneficiários destes fundos, evidenciaram o intuito de garantir a aplicação de práticas de negócio utilizadas pelas empresas tradicionais do setor corporativo em vez daquelas utilizadas no setor social.
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Chowdhury, Shahadat Hossain Civil & Environmental Engineering Faculty of Engineering UNSW. "Mitigating predictive uncertainty in hydroclimatic forecasts: impact of uncertain inputs and model structural form." Publisher:University of New South Wales. Civil & Environmental Engineering, 2009. http://handle.unsw.edu.au/1959.4/43378.
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Hydrologic and climate models predict variables through a simplification of the underlying complex natural processes. Model development involves minimising predictive uncertainty. Predictive uncertainty arises from three broad sources which are measurement error in observed responses, uncertainty of input variables and model structural error. This thesis introduces ways to improve predictive accuracy of hydroclimatic models by considering input and structural uncertainties. The specific methods developed to reduce the uncertainty because of erroneous inputs and model structural errors are outlined below. The uncertainty in hydrological model inputs, if ignored, introduces systematic biases in the parameters estimated. This thesis presents a method, known as simulation extrapolation (SIMEX), to ascertain the extent of parameter bias. SIMEX starts by generating a series of alternate inputs by artificially adding white noise in increasing multiples of the known input error variance. The resulting alternate parameter sets allow formulation of an empirical relationship between their values and the level of noise present. SIMEX is based on the theory that the trend in alternate parameters can be extrapolated back to the notional error free zone. The case study relates to erroneous sea surface temperature anomaly (SSTA) records used as input variables of a linear model to predict the Southern Oscillation Index (SOI). SIMEX achieves a reduction in residual errors from the SOI prediction. Besides, a hydrologic application of SIMEX is demonstrated by a synthetic simulation within a three-parameter conceptual rainfall runoff model. This thesis next advocates reductions of structural uncertainty of any single model by combining multiple alternative model responses. Current approaches for combining hydroclimatic forecasts are generally limited to using combination weights that remain static over time. This research develops a methodology for combining forecasts from multiple models in a dynamic setting as an improvement of over static weight combination. The model responses are mixed on a pair wise basis using mixing weights that vary in time reflecting the persistence of individual model skills. The concept is referred here as the pair wise dynamic weight combination. Two approaches for forecasting the dynamic weights are developed. The first of the two approaches uses a mixture of two basis distributions which are three category ordered logistic regression model and a generalised linear autoregressive model. The second approach uses a modified nearest neighbour approach to forecast the future weights. These alternatives are used to first combine a univariate response forecast, the NINO3.4 SSTA index. This is followed by a similar combination, but for the entire global gridded SSTA forecast field. Results from these applications show significant improvements being achieved due to the dynamic model combination approach. The last application demonstrating the dynamic combination logic, uses the dynamically combined multivariate SSTA forecast field as the basis of developing multi-site flow forecasts in the Namoi River catchment in eastern Australia. To further reduce structural uncertainty in the flow forecasts, three forecast models are formulated and the dynamic combination approach applied again. The study demonstrates that improved SSTA forecast (due to dynamic combination) in turn improves all three flow forecasts, while the dynamic combination of the three flow forecasts results in further improvements.
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Sjökvist, Julia, and Belinda Medic. "“I see it as my damn responsibility to do what I can so that people become aware of what is happening”: A narrative study about individual perception on climate change." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-22370.
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Klimatförändringarna är ett av de största hoten mot mänskligheten, och konsekvenserna avklimatförändringarna kommer öka både i omfattning och allvar i takt med att den globalauppvärmningen intensifieras. Detta leder till överhängande risker mot många områden i samhället. För att den globala uppvärmningen ska hållas under 2 °C måste omfattande åtgärder tas till inom en snar framtid. I detta har individer en viktig roll. Hur individer upplever risker är viktigt för att förstå deras reaktioner gentemot dem klimatförändringarna. En majoritet av det svenska folket betvivlar inte längre att klimatförändringarna sker. Däremot finns det fortfarande mycket som måste göras på individnivå, eftersom hushåll i Sverige står för 60 % av nationens totala utsläpp av växthusgaser. Samtidigt argumenteras det för att det finns en ökad press från samhället, både när det kommer till aktivism och engagemang i klimatfrågan. Baserat på brådskan i att mildra klimatförändringarna är målet med den här studien att få en bättre förståelse för hur individer med ett redan uttalat intresse eller engagemang om klimatförändringarna upplever dessa och risker kopplade till dem samt hur deras väg mot ett engagemang har sett ut. Vidare ämnar den även undersöka hur deras syn, enligt desjälva har utvecklats samt hur denna synen tar sig uttryck kognitivt, emotionellt ochbeteendemässigt med hjälp av en narrativ livshistoriemetod. Hoppet är att få en ökad förståelse för de faktorer som har varit viktiga i detta engagemang eftersom det kan skapa inblick i de viktiga komponenter som krävs för att främja medvetenhet om klimatförändringar och engagemang. Resultaten visar att klimatförändringarna uppfattas som en moralisk oro som är starkt sammankopplad med rättvisefrågor. Kritiska händelser har lett till ett ökat medvetande om problemet. När konsekvenserna om klimatförändringarna omfamnats har hoten som uppvisas gentemot objects of care och ens kärnvärderingar triggat känslor, ökat ens risk perception och aktiverat personliga normer som lett till känslor av personligt ansvar. Så småningom har dessa faktorer, tillsammans med andra lett till olika typer av engagemang, vilket många gånger har varit en gradvis process.Climate change is one of the biggest threats towards humanity, and the consequences of climate change will increase in magnitude and severity as global warming intensifies. This leads to imminent risks to many areas of society. To keep global warming below 2 °C, major mitigation measures will need to occur in the near future. In this, individuals have an important role. How individuals perceive risk are of importance in order to understand their reactions to them. A majority of Swedish people no longer doubt that climate change is occurring. However, there is still a lot to be done on the individual level, as the households in Sweden stands for 60 % of the nation's total greenhouse gas emissions. At the same time, it is argued that there is an increased pressure from civil society, both when it comes to public activism and engagement in climate change. Based on the urgency in mitigating climate change, the aim of this study is to better understand how individuals with an interest or engagement in climate change perceives climate change and its associated risks and what their road to engagement has looked like. Furthermore, the aim is to better understand how their view, according to them, has evolved and how this view is expressed cognitively, emotionally, and behaviorally with the help of a narrative life-history method. The hope is to gain an understanding of the factors that have been key in their engagement with climate change, as this can bring insight to important components in fostering climate change awareness and engagement in the issue. Results demonstrate that climate change is perceived as amoral concern, linked to issues of justice. Critical events have led to an increased awareness of these issues. When consequences of climate change are grasped, the threats they pose to valued objects of care and core values triggers emotional responses, raised risk perception and activates personal norms leading to feelings of personal responsibility. Eventually these factors, along with others, have led to different engagements in climate change, which many times have been a gradual process.
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Sieiro, Saúl Martins. "Cidades e frentes ribeirinhas. Integração infra-estrutural e multifuncionallidade de espaços em cenários de alterações climáticas em Lisboa." Master's thesis, Faculdade de Arquitectura de Lisboa, 2012. http://hdl.handle.net/10400.5/5453.
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Borra, Venkata Shesha Vamsi. "Whiskers: The Role of Electric Fields in the Formation Mechanism and Methods for Whisker Growth Mitigation." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1513381893591481.
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Eriksson, Elin. "Initial nutrient retention capacity in a constructed wetland : Evaluating the effectiveness of a newly constructed wetland to reduce eutrophication symptoms in a Baltic Sea bay in northern Sweden." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184268.
Full textAbstract:
Since the turn of the last century, a substantial increase in nutrient load to the Baltic Sea is apparent. Adding the ongoing environmental change with raising temperatures and increased precipitation, this will continue to have a prominent environmental impact on our coastal ecosystems, especially in northern latitudes. Constructed wetlands are becoming more important as a mitigation measure to retain nutrients, however, they are until this day not well studied in northern latitudes. In this paper, nutrient retention in a newly constructed wetland is studied during its first month after activation, as well as potential downstream effects in associated sea bay. An additional literature study compiles information about the current knowledge, use and functionality of wetlands surrounding the Baltic Sea. This is done to widen knowledge regarding effectiveness of wetlands as nutrient traps in general, as well as to compare with the studied wetland. A net retention of 30 % for dissolved organic carbon (DOC) and total phosphorus (TP) was found, as well as 27 % for total nitrogen (TN), 25 % for phosphate (PO43-) and 21 % for nitrate (NO3-). TP was found to be within range of expected retention capacity, when comparing with wetlands included in the synthesis. TN retention, however, seemed to be somewhat greater than in other wetland studies. Furthermore, the retention varied and seemed to be highest during an increased discharge, in the beginning and end of March. This was partly reflected by greater inlet concentrations and transports in most of the parameters during the initial time period. Decreasing temporal trends was seen in concentrations of DOC, total nutrients and NO3- concentrations in the sea bay, indicating an immediate downstream effect of the wetland installation. Findings from the synthesis indicate that there are very few studies in, and thus little knowledge about, wetlands in northern climate. Overall, the results from the pioneer northern wetland in Sörleviken suggest that net retention is possible during its first month post-activation.
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Cortés, Serra Verònica. "Assessing and mitigating bycatch in the artisanal longline fisheries of the Mediterranean = Avaluació i mitigació de les captures accidentals d'ocells marins en la pesca artesanal de palangre del Mediterrani." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/482134.
Full textAbstract:
La mortalitat per captura accidental en les pesqueres de palangre representa una de les principals amenaces per a nombroses espècies d’ocells marins a nivell mundial. En el Mediterrani, aquesta mortalitat esta afectant seriosament a la viabilitat d’algunes poblacions d’ocells, en particular de les baldrigues endèmiques d’aquesta conca. No obstant això, la informació disponible sobre la intensitat i extensió del seu impacte és escassa i fragmentada. Així mateix, encara no s’ha implementat cap tipus de mesura per evitar aquesta mortalitat.
La present tesis pretén avaluar i contribuir al coneixement sobre la problemàtica de les captures accidentals d’ocells marins en la pesca de palangre de l’oest del Mediterrani, així com identificar l’estratègia de mitigació més adient per a la flota estudiada. En particular, l’estudi s’ha focalitzat en els palangrers de fons ja que fan servir arts més perillosos per als ocells i, a més, existeix una menor informació disponible.
En primer lloc, aquest estudi demostra una elevada mortalitat d’ocells marins als palangres, en particular de les 3 espècies endèmiques de baldrigues: cendrosa (Calonectris diomedea), balear (Puffinus mauretanicus) i mediterrània (P. yelkouan), la qual cosa posa de manifest la necessitat urgent de desenvolupar accions efectives per reduir les captures accidentals d’aquestes espècies. A més, s’ha pogut identificar diversos factors temporals, operacionals, espacials i meteorològics que influeixen en el risc de captura accidental, encara que destaca particularment l’estació de l’any i el moment del dia que es realitza la calada. Altres factors influents són el tipus d’esquer, les condicions de vent, la configuració del palangre, el nombre d’hams calats i la distància a les colònies de cria.
En segon lloc, s’ha observat que la falta de disponibilitat dels descarts proveïts per la pesca d’arrossegament incita a que les baldrigues cendroses acudeixin amb major intensitat als palangrers, incrementant així el risc de captura accidental. Consegüentment, la imminent normativa adoptada per la Unió Europea, la qual pretén prohibir els descarts, podria agreujar el problema de les captures accidentals.
En tercer lloc, l’examen de les baldrigues capturades accidentalment als palangres demostra l’existència d’una mortalitat desigual a nivell poblacional. Els adults són la classe d’edat més afectada. Així mateix, existeix un biaix cap a un dels sexes que varia entre períodes de cria i espècies. També s’ha trobat que la mortalitat als palangres en l’àrea d’estudi està afectant fonamentalment a les poblacions locals (Illes Balears), encara que també són capturades baldrigues provinents d’altres colònies, especialment durant l’època de migració.
Per últim, l’assaig de diversos mètodes de mitigació adaptats als palangrers demersals, demostra que, fins al moment, la calada nocturna seria el mètode més eficaç per reduir les captures accidentals sense afectar les captures objectiu o altres espècies no comercials quan la pesca va dirigida al lluç europeu. Tanmateix, seria necessari confirmar els seus efectes sobre altres espècies objectiu de la flota. A més, una restricció temporal de l’activitat durant els mesos més conflictius podria reduir considerablement aquesta problemàtica, encara que s’hauria d’avaluar els seus efectes sobre el rendiment pesquer. Altres mètodes serien l’increment de la taxa d’enfonsament del palangre o evitar l’ús d’esquers atractius per als ocells. Malgrat tot, la alta diversitat d’estratègies i arts de pesca dificulta la identificació dels mètodes que puguin ser aplicables al conjunt de la flota. Consegüentment, es recomana constituir un joc de diferents mesures de mitigació que puguin ser adaptades a la major part dels mètodes de pesca.Bycatch mortality in longline fisheries is considered the main threat for numerous seabirds worldwide. In the Mediterranean, this mortality is seriously affecting the viability of some populations. However, the information available on the level and extent of its impact is scarce. Likewise, no mitigation strategy has yet been implemented in the fleet. The present thesis aims to asses and contribute to the knowledge about the seabird bycatch in longline fisheries of western Mediterranean, as well as to identify the most appropriate mitigation strategy for the fleet. The study has focused on demersal longliners, since they use the most dangerous gear for seabirds and also because there is little information available. This study shows a high seabird mortality on longlines, in particular of the three endemic shearwaters: Scopoli’s (Calonectris diomedea), Balearic (Puffinus mauretanicus) and Mediterranean (P. yelkouan), calling for urgent actions to reduce their bycatch rates. There are several factors influencing on bycatch risk, but the most important are the season and the setting time. Other influential factors are the bait type, wind conditions, longline configuration, proximity to the colonies and the number of hooks set. Moreover, in Scopoli’s shearwater, the reduction of discards by trawlers led to increased interaction between these seabirds and longliners, thus increasing the bycatch risk. Consequently, the incoming legislation that intends to ban discards will likely aggravate this problem. This study also shows adult- and sex-biased mortality in longline fisheries. In addition, this mortality is more pronounced but not limited to the local colonies. It appears that night setting would be the most effective method to reduce bycatch without compromising target or non-commercial species. However, this should be confirmed in longliners targeting species other than European hake. A temporal closure of the fishery is also a promising strategy, although its effects on fishing activity should be carefully evaluated. Others methods include increasing the longline sink rate and avoiding baits attractive to seabirds. The high diversity of strategies and gears hampers the identification of solutions applicable to the whole fleet. Consequently, it would be necessary to establish a set of different measures that can be adapted to the majority of fishing methods.
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"Methodical Design Approaches to Multiple Node Collection Robustness for Flip-Flop Soft Error MItigation." Doctoral diss., 2015. http://hdl.handle.net/2286/R.I.29650.
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abstract: The space environment comprises cosmic ray particles, heavy ions and high energy electrons and protons. Microelectronic circuits used in space applications such as satellites and space stations are prone to upsets induced by these particles. With transistor dimensions shrinking due to continued scaling, terrestrial integrated circuits are also increasingly susceptible to radiation upsets. Hence radiation hardening is a requirement for microelectronic circuits used in both space and terrestrial applications.
This work begins by exploring the different radiation hardened flip-flops that have been proposed in the literature and classifies them based on the different hardening techniques.
A reduced power delay element for the temporal hardening of sequential digital circuits is presented. The delay element single event transient tolerance is demonstrated by simulations using it in a radiation hardened by design master slave flip-flop (FF). Using the proposed delay element saves up to 25% total FF power at 50% activity factor. The delay element is used in the implementation of an 8-bit, 8051 designed in the TSMC 130 nm bulk CMOS.
A single impinging ionizing radiation particle is increasingly likely to upset multiple circuit nodes and produce logic transients that contribute to the soft error rate in most modern scaled process technologies. The design of flip-flops is made more difficult with increasing multi-node charge collection, which requires that charge storage and other sensitive nodes be separated so that one impinging radiation particle does not affect redundant nodes simultaneously. We describe a correct-by-construction design methodology to determine a-priori which hardened FF nodes must be separated, as well as a general interleaving scheme to achieve this separation. We apply the methodology to radiation hardened flip-flops and demonstrate optimal circuit physical organization for protection against multi-node charge collection.
Finally, the methodology is utilized to provide critical node separation for a new hardened flip-flop design that reduces the power and area by 31% and 35% respectively compared to a temporal FF with similar hardness. The hardness is verified and compared to other published designs via the proposed systematic simulation approach that comprehends multiple node charge collection and tests resiliency to upsets at all internal and input nodes. Comparison of the hardness, as measured by estimated upset cross-section, is made to other published designs. Additionally, the importance of specific circuit design aspects to achieving hardness is shown.Dissertation/Thesis
Doctoral Dissertation Electrical Engineering 2015
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Crane, Molly Kay. "Polarization techniques for mitigation of low grazing angle sea clutter." Thesis, 2017. https://hdl.handle.net/2144/20852.
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Maritime surveillance radars are critical in commerce, transportation, navigation, and defense. However, the sea environment is perhaps the most challenging of natural radar backdrops because maritime radars must contend with electromagnetic backscatter from the sea surface, or sea clutter. Sea clutter poses unique challenges in very low grazing
angle geometries, where typical statistical assumptions regarding sea clutter backscatter do not hold. As a result, traditional constant false alarm rate (CFAR) detection schemes may yield a large number of false alarms while objects of interest may be challenging to detect. Solutions posed in the literature to date have been either computationally impractical or lacked robustness.
This dissertation explores whether fully polarimetric radar offers a means of enhancing detection performance in low grazing angle sea clutter. To this end, MIT Lincoln Laboratory funded an experimental data collection using a fully polarimetric X-band radar assembled largely from commercial off-the-shelf components. The Point de Chene Dataset, collected on the Atlantic coast of Massachusetts’ Cape Ann in October 2015, comprises multiple sea states, bandwidths, and various objects of opportunity. The dataset also comprises three different polarimetric transmit schemes. In addition to discussing the radar, the dataset, and associated post-processing, this dissertation presents a derivation showing that an established multiple input, multiple output radar technique provides a novel means of simultaneous polarimetric scattering matrix measurement. A novel scheme for polarimetric radar calibration using a single active calibration target is also presented.
Subsequent research leveraged this dataset to develop Polarimetric Co-location Layering (PCL), a practical algorithm for mitigation of low grazing angle sea clutter, which is the most significant contribution of this dissertation. PCL routinely achieves a significant reduction in the standard CFAR false alarm rate while maintaining detections on objects of interest. Moreover, PCL is elegant: It exploits fundamental characteristics of both sea clutter and object returns to determine which CFAR detections are due to sea clutter. We demonstrate that PCL is robust across a range of bandwidths, pulse repetition frequencies, and object types. Finally, we show that PCL integrates in parallel into the standard radar signal processing chain without incurring a computational time penalty.
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Bostwick, Angela Sue. "Use of Shark Shapes to Reduce Incidental Capture of Sea Turtles in the Long-Line Fisheries." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8409.
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An estimated 250,000 loggerhead (Caretta caretta) and leatherback
(Dermochelys coriacea) sea turtles are taken each year as incidental catch by the pelagic
long-line fishing industry. Various gear and bait modifications as well as time/area
closures to fishing, enacted to reduce anthropogenic impacts on sea turtles, have been
ineffective or incompatible with regional fishery interests. Chemosensory and auditory
deterrents have yielded little benefit thus far in repelling sea turtles from long-lines. The
fact that sea turtles are highly visual animals has precipitated studies of the efficacy of
using shark shapes to repulse them from long-lines. Previous shark-shape studies
yielded promising results, but their design lacked statistical rigor. The present study
examined the response of 42 captive-reared loggerhead sea turtles (Caretta caretta) to a
shark-shape model at the NOAA Sea Turtle Facility in Galveston, TX. To measure
repulsive effect, time taken to consume squid bait beneath the shark model was
compared to that for controls in which loggerheads were offered squid beneath a
spherical object or a bare squid (i.e., no object control) in a captive setting. Additional
responses compared among these three treatments were time spent near treatment, number of breaths taken, approaches to the treatment, and avoidance behaviors displayed
(e.g., turning carapace toward treatment).
Loggerheads exhibited anti-predator behavior toward the shark model, taking
significantly more time to consume squid bait beneath the shark model than for the other
two treatments. Turtles also spent significantly more time opposite the tank from the
shark model, approached it less often, and exhibited more carapace turns to the model.
Some avoidance of the spherical control object also was observed, but was not as
pronounced as that displayed toward the shark model.
While a repulsive effect of the shark model was resolved during the
aforementioned trials, application of such models to reducing long-line fishery bycatch
would require further research to identify a plausible application; numerous shapes
attached to long-line hooks would be very cumbersome. However, it may be plausible
to develop a “boy’s day kite” shark model that would unfurl and “fly” underwater, and
could possibly be clipped to buoy float lines.
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Byrne, Allison. "Pacific oyster (Crassostrea gigas) and Atlantic salmon (Salmo salar) integrated multi-trophic aquaculture in British Columbia: investigation of bivalve growth and natural sea lice mitigation." Thesis, 2016. http://hdl.handle.net/1828/7283.
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The close proximity of net-pen salmon farms and wild Pacific salmon stocks in British Columbia (BC) is an incentive for precautionary management of the environmentally and economically damaging parasites known as sea lice. Bivalves cultured as part of an integrated multi-trophic aquaculture (IMTA) system may contribute natural, preventative louse control through the ingestion of planktonic sea lice larvae. A field trial was conducted to test sea lice mitigation by bivalves at a commercial Atlantic salmon (Salmo salar) farm in BC using Pacific oysters (Crassostrea gigas). Oysters were cultured in trays around one end of the farm and at a reference site approximately 150 m away from August 2013 until August 2014.
Parasitic and planktonic sea lice (Lepeophtheirus salmonis and Caligus clemensi) were monitored before and during oyster deployment, beginning in December 2012. Parasite abundance peaked in January 2013 (6.5 lice/fish, >85% C. clemensi), and the following year in February 2014 (3.3 lice/fish, >80% L. salmonis). Larval density within cages peaked in January, both in 2013 (1.28 larvae/m3) and 2014 (0.96 larvae/m3). Parasite abundance was significantly correlated with both surface salinity (r2= 0.28, p=0.04) and sea lice larval density (r2= 0.65, p=0.01). Observed densities were significantly lower (t=3.41, p=0.009) than those calculated for the site based on water temperature and salinity, the number of adult female lice present, and the approximate number of fish.
Sea lice mitigation by oysters was assessed by comparing monthly sea lice larval densities inside bivalve and non-bivalve fish cages, and by analyzing preserved oyster digestive tracts from January 2014 (when larval densities were highest) for presence of L. salmonis DNA using PCR. Using these methods, no significant evidence of sea lice mitigation was detected. Oyster growth was monitored by measuring whole wet weight, soft tissue wet, dry, and ash-free dry weight, and shell length, width, and height approximately every four months. Oysters were sampled equally across different sides of the farm and at the reference site (~150 m away from the farm) at three depths: 1, 3, and 6 m. All seven measurements increased significantly over time. Effects of side and depth varied by growth parameter; in general, oysters at 1 and 3 m were significantly larger than those at 6 m, and oysters cultured at the reference site were either significantly smaller or the same size as those cultured around the farm. Oysters from select sides were consistently, significantly larger than those from other sides and from the reference site.
Overall, the findings suggest that sea lice larvae quickly dispersed away from the farm after hatching and were not significantly impacted by bivalve presence around the fish cages. Bivalves grew significantly larger over time and size was significantly impacted by both depth and side of the fish cage. While no evidence of larval sea lice reduction/ingestion by cultured bivalves was detected, this study provides information on all sea lice stages present throughout an Atlantic salmon production cycle, as well as the first detailed growth analysis of Pacific oysters cultured alongside farmed Atlantic salmon in BC.Graduate
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byrneaa@gmail.com
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Tawana, Xoliswa. "A critical investigation of the role of community learning centres in mitigating gender disparities in the Cacadu district of the Eastern Cape." Thesis, 2019. http://hdl.handle.net/10500/25962.
Full textAbstract:
This study investigated issues of gender discrimination in the Cacadu district of the Eastern Cape and the possible role that Community Learning Centres could play in mitigating gender disparities in this particular district. The aim of the study was to recommend ways in which Community Learning Centres could assist people in mitigating gender disparities in the Cacadu district of the Eastern Cape. The study examined scholarly and professional publications, both theoretical and empirical, that support or challenge the proposed focal area. The study was underpinned by post-colonial feminism. Contrary to Western feminism, post-colonial feminism is primarily concerned with the representation of women in once colonized countries.The paradigm deemed to be the most appropriate in undergirding this study was a post-colonial indigenous paradigm which can be seen as context based and inclusive of all knowledge systems. The research approach was qualitative and the research design adopted for the study was phenomenological. Two Community Learning Centres (Xola and Zodwa) located in a rural and an urban area respectively in the Cacadu district of the Eastern Cape were selected by purposive sampling. Data gathering was conducted through semi-structured interviews and focus group discussions. Three adult educators volunteered to participate in individual interviews and twenty-four adult learners volunteered to participate in focus group discussions. Findings indicated that Community Learning Centres in their attempt to promote equity and redress do not help people mitigate gender disparities in their daily lives in the Cacadu district of the Eastern Cape. Based on the findings, it was found that gender disparities emanate not only in the home, but also in Community Learning Centres in the Cacadu district of the Eastern Cape. Finally, strategies were identified in the form of educational practices, processes and developments to assist people to mitigate gender disparities in their daily lives in the Cacadu district of the Eastern Cape. Such educational strategies should be characterised by fairness, equality and the values embedded in social justice with reference to the role of women in society.Educational Foundations
D. Ed. (Socio-Education)
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Costa, Raquel Marques. "Uma nova identidade na diferença: intersecções entre o urbanismo e as alterações climáticas - caso de Lisboa." Master's thesis, 2016. http://hdl.handle.net/10071/13276.
Full textAbstract:
O presente relatório incide sobre as alterações climáticas (AC), um tema em constante atualização.
As alterações globais são mudanças que ocorrem à escala planetária no sistema terrestre, que podem
dividir-se em naturais ou antropogénicas, isto é, provocadas por atividades humanas, e é uma questão
inexorável. O aumento da frequência dos eventos extremos é uma realidade, a subida da temperatura
e do nível médio do mar, maior frequência de ondas de frio e calor, secas e inundações, as alterações
dos padrões de precipitação e tempestades (IPCC, 2007) e, face a esta problemática, existem dois
tipos de respostas que se complementam: adaptação e mitigação (SIAM, P.5).
Quando na realidade o mais urgente é encontrar formas de chegar a um consenso global e combater
de frente as AC, investigar as vulnerabilidades territoriais é uma mais valia para a adaptação às AC no
domínio do ordenamento territorial, existindo atualmente, casos de estudo e estratégias adotadas em
países díspares. A adaptação territorial em Portugal, é relativamente inexplorada, contrapondo aos
níveis das medidas de mitigação e da adaptação, sobretudo no que respeita aos recursos hídricos e
solares.
A elaboração deste documento foi dividida em dois componentes que se suportam mutuamente, sendo
indissociáveis, e ambos contêm uma análise gráfica e critica.
Um subdivide-se por pesquisas e reflexões, acerca de temas relacionados com as AC e outros que
surjam por acréscimo num âmbito global; o segundo refere-se especificamente a Lisboa, com o objetivo
de compreender qual o impacto que este fenómeno terá na frente ribeirinha, e as consequentes
alterações do nível do mar causadas por estas.The present dissertation focus the climatic change, an issue always being up dated by the experts. The global changes are those which occur on a global scale on our planet affecting the entire Earth system and they may be divided into natural and anthropogenic, that is, caused by human activities, and it is an inexorable matter. The increased frequency of extreme events is a reality, such as rising temperatures as well as the sea level, more frequent cold and heat waves, droughts and floods, changes in precipitation patterns and storms (IPCC, 2007), and two types of answers address this problematic issue, there are two types of answers: adaptation and mitigation (SIAM, P.5). In reality, the most urgent is to find ways to reach a global consensus to fight the climate change. In order to adjust the land use planning towards climate change, investigation regarding the territorial vulnerabilities should be implemented. Presently there are studies and strategies implemented in different countries concerning this matter. In Portugal, the territorial adjustment is relatively unexplored, in a contrast towards the levels of mitigation (reduction) and adaption measures regarding, especially, the water and the solar resources. The present document is divided into two components that support each other and both contain a graphical and critical analysis. The first is organizad by a research state of art and reflections on the themes connected to climate change and also others which may arise by growth on a global context; the second refers specifically to Lisbon, to understand the impact that this phenomenon will have on the riverfront, and the consequent changes in sea level.