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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Seleção de áreas aptas a disposição de lodo de estações de tratamento de esgoto com fins agrícolas / Selection of areas suitable for the disposal of sludge stations sewage treatment for agriculture

LESSA, Alyne Alves 03 September 2010 (has links)
Made available in DSpace on 2014-07-29T15:01:44Z (GMT). No. of bitstreams: 1 alyne alves lessa.pdf: 7711831 bytes, checksum: 78548ae6e986fbc5b09fe7e22519a603 (MD5) Previous issue date: 2010-09-03 / Overcrowding in urban centers has spawned many impacts on the environment, highlighting the waste generated by their activities. To properly allocate these wastes, technologies are developed such as those involved in sewage treatment. However, this form of treatment also generates waste, which must be treated and disposed of properly. The sludge is a byproduct of sewage treatment and has few alternatives available, among which, the agricultural disposition for purposes of soil conditioning or recovery of degraded areas. The soil, however, must have received the favorable characteristics of this type of material so as not to create conditions for growth of bacteria is not eliminated in the sludge treatment and prevent contamination of groundwater and surface water. Thus, this study aimed to classify areas as to the suitability of the application of sludge sewage treatment station of Goiania, a radius of 46 km from that station, using the geographic information system. To achieve this goal, we proceeded to the identification of areas considered unsuitable to receive the sludge by CONAMA Resolution 375/2006 of MMA. Then, the areas that had no restrictions were analyzed for ability to use the land for sludge application from the characteristics of the following environmental factors: hydromorphism, fertility, texture, depth, drainage and stoniness of the soil, topography and beyond susceptibility to soil erosion. Studies for the radii of 46 and 20 km by the restrictions set by the resolution showed that the total area of study 25.5 and 43%, respectively, are unsuitable for sludge application, attending many of the weaknesses of the environmental field as observed for the hydromorphism factor and soil drainage. Since environmental factors texture, stoniness and depth restrictions were preventing the release of silt in some areas, while the fertility of the soil proved ideal for this purpose. Considering all the environmental factors, the area shows unfitness to sludge application on the order of 14.5% of the land to the radius of 46 km and 8.3% for the radius of 20 km, which added to the regulatory restriction excludes 40% and 51%, respectively, for this type of use. The areas suitable for agricultural sludge disposal account for 51.3% of total area, with 8.7% of the land with strong environmental restrictions on the radius of 46 km, while for the 20 km radius of these values are 45 and 3 7%, respectively. The best areas for sludge application in both areas - 20 km and 46 - are located in the northern study area. / A aglomeração humana em centros urbanos tem gerado muitos impactos ao meio ambiente, destacando-se os resíduos produzidos por suas atividades. Para destinar corretamente estes resíduos, tecnologias são desenvolvidas como as envolvidas no tratamento dos esgotos. Entretanto, esta forma de tratamento também gera resíduos, os quais devem ser tratados e dispostos adequadamente. O lodo é um dos subprodutos do tratamento do esgoto doméstico e possui algumas alternativas de disposição, dentre as quais, a disposição agrícola com fins de condicionamento do solo ou mesmo recuperação de áreas degradas. O solo, contudo, deve ter características favoráveis ao recebimento deste tipo de material, de modo a não criar condições para proliferação de bactérias não eliminadas no tratamento do lodo e evitar a contaminação das águas subterrâneas e superficiais. Deste modo, este trabalho teve como objetivo classificar áreas quanto à aptidão a aplicação do lodo da Estação de Tratamento de Esgoto de Goiânia, num raio de 46 km e 20 km a partir da referida Estação, utilizando o sistema de informações geográficas. Para atingir este objetivo, procedeu-se à identificação das áreas consideradas inaptas ao recebimento do lodo pela Resolução CONAMA 375/2006 do MMA. Em seguida, as áreas que não apresentaram restrições foram submetidas à análise da capacidade de uso do solo para aplicação do lodo a partir das características dos seguintes fatores ambientais: hidromorfismo, fertilidade, textura, profundidade, drenagem e pedregosidade do solo, além do relevo e da suscetibilidade dos solos à erosão. Os estudos para os raios de 46 e 20 km pelas restrições estabelecidas pela resolução demonstraram que da área total de estudo 25,5 e 43%, respectivamente, são inaptas à aplicação do lodo, atendendo muitas das fragilidades ambientais do terreno como o observado para os fatores hidromorfismo e drenagem do solo. Já os fatores ambientais textura, pedregosidade e profundidade apresentaram restrições que impedem o lançamento do lodo em algumas áreas, enquanto a fertilidade do solo mostrou-se ideal para esta finalidade. Considerando todos os fatores ambientais, a área apresenta inaptidão à aplicação do lodo na ordem de 14,5% das terras para o raio de 46 km e 8,3% para o raio de 20 km, que somadas à restrição normativas, exclui 40% e 51%, respectivamente, para este tipo de uso. As áreas aptas à disposição agrícola do lodo respondem por 51,3% da área total, estando 8,7% das terras com fortes restrições ambientais considerando o raio de 46 km, enquanto para o raio de 20 km esses valores são de 45 e 3,7%, respectivamente. As melhores áreas para aplicação do lodo, em ambas as áreas - 46 e 20 km - estão localizadas na região norte da área de estudo.
262

Nouvelle méthodologie générique permettant d’obtenir la probabilité de détection (POD) robuste en service avec couplage expérimental et numérique du contrôle non destructif (CND) / New generic methodology to obtain robust In-Service Probability Of Detection (POD) coupling experimental and numerical simulation of Non-Destructive Test (NDT)

Reseco Bato, Miguel 17 May 2019 (has links)
L’évaluation des performances des procédures de Contrôle Non Destructifs (CND) en aéronautique est une étape clé dans l’établissement du dossier de certification de l’avion. Une telle démonstration de performances est faite à travers l’établissement de probabilités de détection (Probability Of Detection – POD), qui intègrent l’ensemble des facteurs influents et sources d’incertitudes inhérents à la mise en œuvre de la procédure. Ces études, basées sur des estimations statistiques faites sur un ensemble représentatif d’échantillons, reposent sur la réalisation d’un grand nombre d’essais expérimentaux (un minimum de 60 échantillons contenant des défauts de différentes tailles, qui doivent être inspectés par au moins 3 opérateurs [1]), afin de recueillir un échantillon suffisant pour une estimation statistique pertinente. Le coût financier associé est élevé, parfois prohibitif, et correspond majoritairement à la mise en œuvre des maquettes servant aux essais. Des travaux récents [2-5] ont fait émerger une approche de détermination de courbes POD utilisant la simulation des CND, notamment avec le logiciel CIVA. L’approche, dite de propagation d’incertitudes, consiste à : - Définir une configuration nominale d’inspection, - Identifier l’ensemble des paramètres influents susceptibles de varier dans l’application de la procédure, - Caractériser les incertitudes liées à ces paramètres par des lois de probabilités, - Réaliser un grand nombre de simulations par tirage aléatoire des valeurs prises par les paramètres variables selon les lois de probabilités définies. Le résultat de cet ensemble de simulations constitue enfin la base de données utilisée pour l’estimation des POD. Cette approche réduit de façon très importante les coûts d’obtention des POD mais est encore aujourd’hui sujette à discussions sur sa robustesse vis-à-vis des données d’entrée (les lois de probabilité des paramètres incertains) et sur la prise en compte des facteurs humains. L’objectif de cette thèse est de valider cette approche sur des cas d’application AIRBUS et d’en améliorer la robustesse afin de la rendre couramment utilisable au niveau industriel, notamment en la faisant accepter par les autorités de vol (FAA et EASA). Pour ce faire le thésard devra mener des campagnes de validations des codes de simulation des CND, mettre en œuvre la méthodologie décrite plus haut sur les cas d’application AIRBUS, puis proposer et mettre en œuvre des stratégies d’amélioration de la robustesse de la méthode vis-à-vis des données d’entrée et des facteurs liés à l’humain. / The performance assessment of non-destructive testing (NDT) procedures in aeronautics is a key step in the preparation of the aircraft's certification document. Such a demonstration of performance is done through the establishment of Probability of Detection (POD) laws integrating all sources of uncertainty inherent in the implementation of the procedure. These uncertainties are due to human and environmental factors in In-Service maintenance tasks. To establish experimentally these POD curves, it is necessary to have data from a wide range of operator skills, defect types and locations, material types, test protocols, etc. Obtaining these data evidences high costs and significant delays for the aircraft manufacturer. The scope of this thesis is to define a robust methodology of building POD from numerical modeling. The POD robustness is ensured by the integration of the uncertainties through statistical distributions issued from experimental data or engineering judgments. Applications are provided on titanium beta using high frequency eddy currents NDT technique. First, an experimental database will be created from three environments: laboratory, A321 aircraft and A400M aicraft. A representative sample of operators, with different certification levels in NDT technique, will be employed. Multiple inspection scenarios will be carried out to analyze these human and environmental factors. In addition, this study will take into account the impact of using different equipments in the HFEC test. This database is used, subsequently, to build statistical distributions. These distributions are the input data of the simulation models of the inspection. These simulations are implemented with the CIVA software. A POD module, based on the Monte Carlo method, is integrated into this software. This module will be applied to address human and ergonomic influences on POD. Additionally this module will help us to understand in a better way the equipment impact in POD curves. Finally, the POD model will be compared and validated with the experimental results developed.
263

Reptilförekomster och kopplingar till miljöfaktorer på Billingen : Inventering av reptilfauna med artificial cover objects på lokal nivå i Västsverige / Reptile occurences and connections to environmental factors on Billingen : Survey of reptile fauna with artificial cover objects on a local scale in Western Sweden

Carlquist Segell, Maja January 2021 (has links)
Förlust av biologisk mångfald är den planetära gräns som överskrids mest, och medför bland de största hoten mot biosfärens integritet. Reptiler är funktionella delar i ekosystem, men habitatförlust, förändrad markanvändning och klimatförändringar orsakar globala populationsminskningar. Ekologisk övervakning möjliggör förståelse för arters tillstånd, och utveckling av bevarandeåtgärder. Denna förekomststudie syftar till att undersöka lokal reptilfauna, som inventerades med artificial cover objects (ACO) i två naturområden på Billingen, ett av de västsvenska platåbergen, i Skövde kommun 2021. Data från miljöbeskrivning och inventering samt över väderförhållanden samlades in, och samband mellan observationer och miljöfaktorer testades med statistiskt t-test för positiva skillnader mellan datagrupper. Skogsödla (Zootoca vivipara), kopparödla (Anguis fragilis), snok (Natrix natrix) och huggorm (Vipera berus),alla allmänna reptilarter i regionen, observerades i undersökningsområdet. Nio observationer gjordes under 20 regnfria dagar i juni och juli, med temperaturer över 18°C. Biotopkvaliteterna brynmiljöer och nektarresurser, solexponering och de öppna biotoperna beteshage och elledningsgata, förekom i signifikant högre utsträckning där observationer gjordes, än på platser utan observationer. Markfuktighet, mänsklig närvaro, naturvärden och områdesskydd uppvisade ingen signifikans. Resultaten överensstämmer med andra studier om reptilarternas habitat, och kan ses gälla på lokal nivå trots ett relativt litet dataunderlag. Effektiva reptilbevarande åtgärder i närområdet kan innebära upprätthållande och skapande av ytor med hög solinstrålning och strukturell komplexitet, fortsatt men inte utökat lågintensivt naturbete, samt ökad halt avträdslagsblandning och brynmiljöer i produktionsskog. Kunskapen kring reptilers ekologi, samtövervakningen av populationer, behöver utökas. Det rekommenderas vidare studier om reptiler, deras habitat och bevarande av biologisk mångfald på lokala nivåer. / Biodiversity loss is the most exceeded planetary boundary, and entails some of the largest threats against biosphere integrity. Reptiles are functional parts of ecosystems, but habitat loss and changes in land use and climate are causing global population declines. Ecological monitoring enables understanding of species’ conditions, and development of conservation measures. This occurrence study aims to investigate local reptile fauna, surveyed using artificial cover objects (ACOs), in two areas on Billingen, one of Western Sweden’s table mountains, in Skövde municipality 2021. Environmental, survey and weather data were collected, and relations between observations and environmental factors were tested with statistical t-test for positive differences between data groups. Zootoca vivipara, Anguis fragilis, Natrix natrix and Vipera berus, all regionally common reptile species, were observed in the investigated area. Nine observationswere made during 20 rain-free days in June and July, with temperatures above 18°C. Solarexposure, biotope qualities Forest edges and Nectar resources, and the open biotopes Pasture and Powerline corridor, occurred in significantly higher extent where observations were made, than on sites without observations. Soil moisture, Human presence, Natural values and Environmental protection did not exhibit any significance. The results correspond to other studies on the reptilespecies’ habitat, and may apply on a local scale despite a relatively small data amount. Effective conservation measures for local reptiles can imply maintaining and creating spaces with high solar radiation and structural complexity, continued but not extended low-intensity grazing, and increasing tree species mixture and edge zones in production forests. Knowledge on reptile ecology and population monitoring needs to increase. Further studies on reptiles and biodiversity conservation on local scales are recommended.
264

Como el cantar del coquí: Educators of the Puerto Rican Diaspora in the U.S. Describe What Resilience Means to Them

Balotta, Maria 08 August 2011 (has links)
No description available.
265

The feasibility of the statement of generally accepted accounting practice for small and medium enterprises / Daniël Petrus Schutte

Schutte, Daniël Petrus January 2011 (has links)
Governments are becoming increasingly aware of SMEs as economical role players. As a result many initiatives were introduced to address the unique challenges of the SME sector. One of these initiatives was the introduction of a global accounting framework for SMEs by the International Accounting Standards Board entitled the IFRS for SMEs. South Africa became the first country to formally adopt the contents thereof as the Statement of GAAP for SMEs. The adoption of a formal accounting framework by SMEs is however challenged by, amongst other factors, the informal nature of SMEs, limited global focus, the involvement of owner–managers and different classifications of SMEs worldwide. Owing to these unique attributes it is possible that SMEs have alternative informational needs and as a result the impact of environmental factors on the adoption of the Statement of GAAP for SMEs was considered. Culture is considered the most important environmental factor affecting the accounting environment. The Value Survey Model of Hofstede was utilised to determine cultural dimensions of accounting students (n = 301) in South Africa and the United Kingdom (UK). The cultural dimensions were extended to the accounting values of Gray after which a distinct set of accounting values was identified for i) the adoption of formal, global and prescriptive accounting standards, ii) based on principles iii) by an informal SME sector. The results also revealed distinct cultural differences within South Africa as well as between South Africa and the UK. Thereafter the contents of the Statement of GAAP for SMEs/IFRS for SMEs were evaluated against reporting practices of the SME sector in South Africa. Firstly, an assessment of the contents was conducted amongst SME accountants (n = 157) using a five–point Likert–type scale. Secondly, financial statements compiled by the SME sector in South Africa were analysed to determine the relevance of the contents of the illustrative financial statements contained in the Statement of GAAP for SMEs. The analysis entailed a consolidation of a sample of SME financial statements from South Africa (n = 100). The study revealed that the accounting environment of the SME sector is affected by a wide range of environmental and related factors. These factors were summarised and discussed and recommendations for future research were made. / Thesis (Ph.D. (Accounting))--North-West University, Potchefstroom Campus, 2011.
266

The feasibility of the statement of generally accepted accounting practice for small and medium enterprises / Daniël Petrus Schutte

Schutte, Daniël Petrus January 2011 (has links)
Governments are becoming increasingly aware of SMEs as economical role players. As a result many initiatives were introduced to address the unique challenges of the SME sector. One of these initiatives was the introduction of a global accounting framework for SMEs by the International Accounting Standards Board entitled the IFRS for SMEs. South Africa became the first country to formally adopt the contents thereof as the Statement of GAAP for SMEs. The adoption of a formal accounting framework by SMEs is however challenged by, amongst other factors, the informal nature of SMEs, limited global focus, the involvement of owner–managers and different classifications of SMEs worldwide. Owing to these unique attributes it is possible that SMEs have alternative informational needs and as a result the impact of environmental factors on the adoption of the Statement of GAAP for SMEs was considered. Culture is considered the most important environmental factor affecting the accounting environment. The Value Survey Model of Hofstede was utilised to determine cultural dimensions of accounting students (n = 301) in South Africa and the United Kingdom (UK). The cultural dimensions were extended to the accounting values of Gray after which a distinct set of accounting values was identified for i) the adoption of formal, global and prescriptive accounting standards, ii) based on principles iii) by an informal SME sector. The results also revealed distinct cultural differences within South Africa as well as between South Africa and the UK. Thereafter the contents of the Statement of GAAP for SMEs/IFRS for SMEs were evaluated against reporting practices of the SME sector in South Africa. Firstly, an assessment of the contents was conducted amongst SME accountants (n = 157) using a five–point Likert–type scale. Secondly, financial statements compiled by the SME sector in South Africa were analysed to determine the relevance of the contents of the illustrative financial statements contained in the Statement of GAAP for SMEs. The analysis entailed a consolidation of a sample of SME financial statements from South Africa (n = 100). The study revealed that the accounting environment of the SME sector is affected by a wide range of environmental and related factors. These factors were summarised and discussed and recommendations for future research were made. / Thesis (Ph.D. (Accounting))--North-West University, Potchefstroom Campus, 2011.
267

Exploring socio-economic, cultural and environmental factors influencing young women's vulnerability to HIV : a study in Sunnyside (Pretoria)

Tlhako, Regina Kgabo 04 1900 (has links)
Women face a greater risk of HIV infection worldwide than men. This study explored socio-economic, cultural and environmental factors influencing young women’s vulnerability to HIV. A quantitative explorative study was conducted among young women in Sunnyside, Pretoria. A sample of 158 young women in the age group 18 to 24 years from all language groups was randomly selected to participate in this study. The findings showed that poverty, peer pressure and multiple sexual partners were the main factors that influenced young women in Sunnyside’s vulnerability to HIV. Behavioural change and social change were recommended as long-term processes, which need to be taken into consideration. Findings from the Sexual Relationship Power Scales show that young women between 18 and 21 years experience physical abuse, emotional abuse, sexual abuse and forced sex in their relationships. The study concluded with specific recommendations for the successful implementation of policy makers and planners to protect women. / Health Studies / M.A. (Social Behaviour Studies in HIV/AIDS)
268

The Spatial Relationship Between Septic System Failure and Environmental Factors in Washington Township, Marion County, Indiana

Hanson, Brian L. 04 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Underground septic systems thrive or fail based on the relationship with their local environment. This paper explores ways environmental variables such as soil type, tree roots, degree of slope, and impervious surfaces affect on-site wastewater treatment systems. It also discusses the effects each of these variables may have on a septic system, and the resulting impact a compromised system may have on the surrounding environment. This research focuses on an approximately 20 square mile area of central Washington Township in Marion County, Indiana. This area of central Indiana contains a large septic system owning population in a sampling of different environments such as wooded areas, hilly areas, and a variety of different soil types.

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