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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.
161

Japanese Indigenous Knowledges and Impacts of Vibrating Energy: Pedagogical Implication in Education

Kawano, Yumiko 01 January 2011 (has links)
The purpose of this study is to engage in a discussion that is currently marginalized in academic spaces, about the notions of energy and impacts of it on students' learning process and accomplishment in the educational space. While teachers' low expectations and negation on racialized students, and hostilities from other peers has been studied, not much attention has been paid to how those teachers' and peers' energy such as hostility has impacted on students' learning process and accomplishment. In this thesis, I employ Japanese Indigenous ways of knowing to explore this theme. However, my discussion about the impact of energy on student learning process is not limited to the Japanese context only; I have expanded the discussion to the Eurocentric educational system as well. My thesis aims to contribute to the instructional and pedagogical implication for classroom teachers.
162

Japanese Indigenous Knowledges and Impacts of Vibrating Energy: Pedagogical Implication in Education

Kawano, Yumiko 01 January 2011 (has links)
The purpose of this study is to engage in a discussion that is currently marginalized in academic spaces, about the notions of energy and impacts of it on students' learning process and accomplishment in the educational space. While teachers' low expectations and negation on racialized students, and hostilities from other peers has been studied, not much attention has been paid to how those teachers' and peers' energy such as hostility has impacted on students' learning process and accomplishment. In this thesis, I employ Japanese Indigenous ways of knowing to explore this theme. However, my discussion about the impact of energy on student learning process is not limited to the Japanese context only; I have expanded the discussion to the Eurocentric educational system as well. My thesis aims to contribute to the instructional and pedagogical implication for classroom teachers.
163

Examining the Economic Implications and Considerations for Continued Involvement in the Conservation Reserve Program in Texas

Schuchard, Laura Mae 2011 August 1900 (has links)
The Conservation Reserve Program (CRP) has become increasingly important in Texas due to the high level of program participation, particularly in the high plains of Texas. There is also a seemingly large amount of CRP contracts that will expire, particularly in the next five years. As these contracts expire, it becomes very important for landowners to evaluate fully the options that are available for future land use. This research focused primarily on the ten counties in Texas having the most acres of CRP enrollment, which include Gaines, Deaf Smith, Lamb, Hale, Floyd, Dallam, Hockley, Terry, Castro, and Swisher Counties. The primary objective was to provide landowners in these counties with a comprehensive list of options available after CRP contract expiration. The options were identified as re-enrollment in CRP, conversion back into crop production, lease land to a tenant as rangeland, or lease land to a tenant as cropland. Latin Hypercube simulation was used to generate a stochastic value for probable net returns per acre for the four options. The four options were then evaluated based on a variety of methods typically used to rank risky alternatives. The results indicate that CRP enrollment is the most preferred option for landowners. Dryland crop production, while it can return very high net returns per acre, also has the highest amount of risk involved. However, it is important to note that the best ranking method and decision are dependent on the specific decision maker and situation. The second objective of the research was to determine if there are measurable economic impacts to the agricultural services industry associated with CRP enrollment. OLS regression models were only run for five of the ten counties in the study area due to a lack of data reported by the Bureau of Economic Analysis. Of the five counties modeled, the Gaines, Dallam, and Hale County models indicated that CRP has played a significant role in the annual earnings of the agricultural services industry. The results suggest that there would be a benefit in conducting further research to examine the relationship between CRP enrollment and the agricultural services sector.
164

Modélisation et impacts à court terme d'un incendie en milieu ouvert sur l'environnement

Hamzi, Rachida 26 November 2008 (has links) (PDF)
Dans le cadre de l'évaluation environnementale des projets, l'analyse de risques d'accidents technologiques majeurs permet d'intégrer l'aspect sécurité dans la prise de décision gouvernementale concernant l'acceptabilité des projets soumis. L'analyse des risques technologiques majeurs s'inscrit dans une démarche plus large de gestion des risques et permet de déterminer les accidents potentiels associés à l'implantation ou à la présence d'une installation industrielle. L'évaluation des conséquences et des effets pour les populations, l'environnement et les territoires voisins contribue à une meilleure gestion des risques et à leur réduction. La mise en place de mesures de sécurité et d'atténuation, comprenant une planification des mesures d'urgence et un programme de gestion de risques adapté à la nature des accidents potentiels majeurs identifiés complète le dispositif. La démarche proposée dans cette thèse combine l'analyse de risque, l'analyse de processus et la simulation numérique, afin d'étudier et d'évaluer les conséquences d'un incendie sur l'environnement, tout au long de la durée de vie d'une installation, en situation normale, accidentelle (phase d'urgence) et au delà (phase post- accidentelle). Cette combinaison est réalisée à l'aide d'outils d'analyse, d'évaluation des impacts environnementaux et de dispersion des polluants, en s'appuyant sur la complémentarité entre ces méthodes. Cette association permet, tout d'abord, d'intégrer les résultats qualitatifs d'une analyse des risques par l'AEE- Aspect Accidentel, aux études du Cycle de Vie d'un produit fournies par l'ACVincendie. Elle permet, ensuite, d'utiliser les données quantitatives issues de l'ICV comme entrées d'un Modèle Numérique de Dispersion. Ce croisement de connaissances fournit aux décideurs des éléments d'aide pour mieux comprendre et évaluer les enjeux, identifier les solutions et discuter des critères à prendre en considération pour une meilleure gestion d'un incendie en milieu ouvert, dans un territoire péri-industriel.
165

Sustainability assessment within the residential building sector: a practical life cycle method applied in a developed and a developing country

Ortiz Rodríguez, Oscar Orlando 18 December 2009 (has links)
More than ever, the residential building sector is concerned with improving the social, economicand environmental indicators of sustainability. In order to overcome the increasing concern of today'sresource depletion, environmental considerations and to address sustainability indicators, a practicallife cycle method has been proposed to decision making integrating environmental and socioeconomicalaspects to analyse the impact of sustainability within the residential building sector usingtwo practical life cycle methods. One method is the Material and Energy Analysis (MEA) which issuggested as an appropriate tool to provide a systematic picture of the direct and physical flows of theuse of natural resources and the other is the environmental management tool of Life CycleAssessment (LCA) as a complement to evaluate environmental impacts throughout the life cycle of thesystem.Furthermore, the method provides sustainability information that facility an adequate decisionmaking towards sustainable development at macro and micro levels. Sustainability assessment atmacro level is determined by exogenous variables that can influence the development of a country.Meanwhile sustainable at the micro level is made within the limits of the whole building life cycle,starting from the construction, use (operation and maintenance) and finishing with the end-of-lifephase. To illustrate it, a case study has been carried out based on the application to two buildings, onelocated in Barcelona, Spain and one situated in Pamplona, Colombia. Then, the main objective of thisthesis is to propose a practical life cycle method including environmental and socio-economicalaspects to evaluate indicators that explicitly measure the residential building sector's impacts. Thisthesis has also provided initiatives for residential dwellings to reduce environmental impacts and assiststakeholders in improving customer patterns during the dwelling life cycle.The findings of this thesis state that the appropriate combination of building materials,improvement in behaviours and patterns of cultural consumption, and the application of governmentcodes would enhance decision-making in the residential building sector towards sustainability. Thedifference in consumption in Colombia and Spanish dwellings is not only due to the variation in resultsfor bio-climatic differences but also because of the consumption habits in each country. Theimportance of consumption habits of citizens and the need to decouple socio-economic developmentfrom energy consumption are sought for achieving sustainability from a life cycle perspective. There isa crucial necessity to provide satisfaction to basic needs and comfort requirements of population withreasonable and sustainable energy consumption.Therefore, there is no doubt that applying environmental managements tools as Life CycleAssessment (LCA) and Material and Energy Analysis (MEA) to the full building life cycle can be veryimportant for reducing environmental loads and thereby improving sustainability indicators. Then, anyimprovement in building sustainability is oriented generally to building materials, energy use and wastemanagement in all phases of the building life cycle, having always in mind that building has to bexxviiiaccessible from an economical and social part of view. The type of standard dwelling variessubstantially depending on the geographic location where it is built. Climate, technological, cultural,socio-economical differences clearly define the standard of a building in any context and in any region.This leads to important differences in the LCA results and it means that any extrapolation of existingEuropean LCA data to the case of a developing country would imply important errors. However, thefunction is always the same, to provide protection and housing for its habitants. / Hoy en día, el sector residencial busca mejorar los indicadores de sostenibilidad en los aspectossociales, económicos y ambientales. Con el fin de considerar la creciente preocupación delagotamiento de los recursos naturales y buscar reducir las emisiones adversa al medio ambiente, unmétodo practico basado en el ciclo de vida se ha propuesto para la evaluación socio-económica yevaluación del impacto ambiental en sector residencial utilizando dos métodos. El primero es elAnálisis de Materiales y de Energía (AME) que proporciona una visión sistemática de los flujosdirectos e indirectos de la utilización de los recursos naturales y el segundo método es el Análisis delCiclo de Vida (ACV) como complemento para evaluar los impactos ambientales en todo el ciclo devida del sistema.Adicionalmente, el método proporciona información de sostenibilidad permitiendo la adecuadatoma de decisiones hacia el desarrollo sostenible en los niveles macro y micro. Evaluación de laSostenibilidad en el nivel macro está determinado por variables exógenas que influyen en eldesarrollo de un país. Mientras tanto, sostenibilidad en el nivel micro hace referencia dentro de loslímites de todo el ciclo de vida de una vivienda, comenzando por la fase de construcción, uso(operación y mantenimiento) y terminando con la fase final. Para ilustrarlo, un caso de estudio ha sidollevado a cabo en la aplicación de dos edificios, uno situado en Barcelona, España y otro situado enPamplona, Colombia. Por consiguiente, el objetivo principal de esta tesis es proponer un método quetenga en cuenta los aspectos medio-ambientales y socio-económicos que tiendan a mejorar lasostenibilidad y que explícitamente midan los impactos del sector de residencial. Esta tesis también propone iniciativas de mejora en las viviendas residenciales que conlleven a reducir los impactos ambientales y asistir a los agentes involucrados del sector.Las conclusiones de esta tesis soportan que la combinación adecuada de materiales deconstrucción, el buen comportamiento en los patrones de consumo, y la aplicación de códigos y leyes mejoraran los aspectos sostenibles en el sector de la construcción. La diferencia en el consumo en las viviendas de Colombia y en las Españolas no sólo se debe a la variación de las diferencias bioclimáticas,sino también por los hábitos de consumo en cada país. Se puede observar la importancia de los hábitos de consumo de los ciudadanos y la necesidad de disociar el desarrollo socioeconómico del consumo de energía. Existe una necesidad fundamental de dar satisfacción a las necesidades básicas y requerimientos de confort de la población con un consumo energético razonable y sostenible.Por lo tanto, no hay duda de que la aplicación de herramientas medioambientales como el análisis del ciclo de vida (ACV) y análisis de materiales y energía (AME) es muy importante para minimizar el impacto ambiental y buscar mejorar los indicadores de sostenibilidad. Queda implícito entonces que cualquier mejora en la sostenibilidad está orientado generalmente a la selección apropiada de materiales de construcción, el uso eficiente de energía y la correcta gestión de residuos en todas las fases del ciclo de vida del edificio, teniendo siempre en cuenta que el edificio tiene que ser accesible desde una parte económica y social. El tipo de vivienda estándar varía sustancialmente dependiendo de la ubicación geográfica donde se construya. Aspectos como el clima, la tecnología, la cultura y las diferencias socio-económicas definen claramente el nivel de un edificio en cualquier contexto y en cualquier región. Esto da lugar a importantes diferencias en los resultados del ACV y significa que cualquier extrapolación de datos europeos existentes del ACV para el caso de un paísen desarrollo implicaría errores importantes. Sin embargo, la función es siempre la misma,proporcionar protección y vivienda para sus habitantes
166

Polarization Effects of Mechanical Impacts on Dispersion Compensating Modules

Dumas, Derek 20 May 2009 (has links)
Novel methods and apparatus used to measure high-speed state of polarization changes are developed. Knowledge of the effects of mechanical impacts on the state of polarization will benefit the reliability of optical communication systems. The impact creates a high-speed but continuous motion of the state of polarization over the Poincar´e sphere. The maximum speed at which the state of polarization changes due to an impact is shown to be higher than what has been reported previously. The investigation into the state of polarization changes led to the discovery of the repeatability and elasticity of state of polarization changes due to mechanical impacts. The repeatability and elasticity allow novel measurements of important polarization effects in optical fibres such as high-speed polarization mode dispersion and rotation vector measurements.
167

Environmental impacts of cage aquaculture in the southeast arm of Lake Malawi: water and sediment quality and food web changes

Gondwe, Mangaliso John Gibson Symon 14 September 2009 (has links)
Lake Malawi is a great lake not only because of its size (30,800 km2) but also because of its unique fish diversity. The lake contains the highest number of freshwater fish species in the world. The fish species are hypothesized to have radiated within the lake, which is 1-2 million years old. The collapse of the capture fishery in Lake Malawi between the 1970s and 1990s led to the launch of cage culture of indigenous fish species in 2004 in the south east arm of the lake. While cage culture has been practiced for many years in temperate lakes and seas, the fish farm in Lake Malawi is the first in the African Great Lakes and, therefore, not much information currently exists that is relevant to the impact of cage culture on such a large, species-rich tropical lake. Consequently, a study was done between January and December, 2007, at the fish farm in Lake Malawi to determine potential impacts of cage wastes on the environment. The study found that, just like in temperate systems where 70-87% of C, N and P added through feed get dispersed into the environment, discharges from fish cages in Lake Malawi were between 71-88% of the nutrients added through feed. The discharges were proportional to the amount of feed added so that as production and feed supply increase over time, more cage wastes would be generated and released into the environment. The discharges were exacerbated by poor stocking and feeding regimes. Production periods were longer (mean of 376±42 days) than if recommended stocking and feeding rates were followed. Feed quality may also have affected production performance and waste generation in the cages, but was not studied. The cage wastes were incorporated into the food web and support the wild fishes in the vicinity of the fish farm. Impacts of the cage wastes on the water column and sediments in the vicinity of the cages were minimal during the study period, probably because of rapid and efficient dispersion of the wastes by strong water currents, that averaged 9.3 cm s-1, through the cages and high consumption of the cage wastes by large numbers of wild fishes which aggregated around the cages. The wild fishes also helped to disperse the cage wastes over a larger area through consumption, translocation and defecation. However, as production increases, the amount of cage wastes generated may overwhelm mitigation by dispersion by water currents and consumption by wild fishes, particularly if many cages are deployed close together and interfere with current flows. Based on my observations, a fish farm that produces 15,000 tonnes fish/yr in Lake Malawi would generate 1249, 113 and 21 megamoles/yr of C, N and P, respectively, that are comparable or higher than DOC, TDN and TDP loadings observed in the most disturbed large river systems draining into Lake Malawi. The impacts of these river systems in Lake Malawi have been well documented, particularly around river mouths and in the more densely populated and shallower southern portion of the lake, where algal communities and their sedimentation rates have begun to change. Cage culture discharges may accelerate these changes.
168

Using GIS for Analysis of the Runway Extension of Margaret Ekpo International Airport, Calabar, Nigeria

Uche, Eugene, Oparah, Charles January 2012 (has links)
This study investigates the proposed extension of the existing runway of Margaret Ekpo International Airport, Calabar, Cross River State, Nigeria. The process involves the application of Geographic Information System (GIS) and several geospatial techniques for analysis and result presentation. The aim of the study was achieved with the following resources: satellite imagery downloaded from the Landsat webpage and processed to generate a land use map of the study area; a Digital Elevation Model (DEM) covering the study area which was downloaded from the Consortium for Spatial Information’s (CSI) webpage and observed ground spot heights along the straight path of the proposed runway extension covering a total length of 2.5km and 200m wide. These datasets were modified, processed and assigned the same coordinate system in order to make them conformal for analysis. A GIS was created with the foregoing resources in conjunction with other geospatial applications such as ERDAS Imagine and Surfer 8 to carry out the analysis. The analysis covered the environmental impacts of the proposed project, its effects on already existing human settlements and the huge cost implications based on certain conditions like the mandatory straight path which has to be maintained as an extension of the existing runway. Other factors considered are; the land use of the extension area, the economic benefits of the project, the accessibility of the area, noise pollution as well as the safety and security issues involved. A summary of the result of our analysis shows features such as residential settlements, roads, swampy areas, valleys and areas of high elevation which will act as obstructions along the proposed  runway path. Also, the total surface area of the proposed runway and the volume of earth material required were calculated. The results achieved from this study shows that GIS and other geospatial tools are indispensable resources in complex planning processes such as facility maintenance and management.
169

Event Tourism Economical and tourstic impacts on regional economy : A study of Polish regions preparations for UEFA EURO 2012

Zima, Kamil January 2011 (has links)
The aim of the study was to examine what the economic and touristic impacts of the sports event - UEFA EURO 2012 - will have on Polish regions. The essay was limited to some specific regions in Poland. Those regions were Gniewino, Malbork, Kalisz, Legionowo, Pommerian Province, Cracow, Olsztyn and Zamosc. The Football Championships that will be held in 2012 are dependent of the big amount of football fans that will came and spend their money in Polish regions. Thanks to the increased consumption this creates demand for local services and products. The generator of spending is the tourism multiplier that is the main link to the touristic expenditure.The multiplier is a catalyst of the region that creates jobs, growing yield, promotion of the region and improvement of its infrastructure and leisure facilities. This is considered as an advantage from an economical and touristic point of view. The economical and tourstic benefits are different for every mentioned region in the study because of their location and link to the UEFA EURO 2012. This study shows only how the different eight regions prepare for the UEFA EURO 2012 and what they think that the negative and positive economical and touristic impacts will gain them. The study gives only a short brief of the football event of what can happen.
170

Polarization Effects of Mechanical Impacts on Dispersion Compensating Modules

Dumas, Derek 20 May 2009 (has links)
Novel methods and apparatus used to measure high-speed state of polarization changes are developed. Knowledge of the effects of mechanical impacts on the state of polarization will benefit the reliability of optical communication systems. The impact creates a high-speed but continuous motion of the state of polarization over the Poincar´e sphere. The maximum speed at which the state of polarization changes due to an impact is shown to be higher than what has been reported previously. The investigation into the state of polarization changes led to the discovery of the repeatability and elasticity of state of polarization changes due to mechanical impacts. The repeatability and elasticity allow novel measurements of important polarization effects in optical fibres such as high-speed polarization mode dispersion and rotation vector measurements.

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