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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.
701

Assessing community capacity for ecosystem management : Clayoquot Sound and Redberry Lake biosphere reserves

Mendis, Sharmalene Ruwanthi 29 October 2004
Biosphere reserves are regions that are internationally recognized for their ecological significance and work towards ecosystem management. The concept of community capacity, as developed in the resource management and health promotion literatures, was applied to two such regions that were designated in 2000: Clayoquot Sound and Redberry Lake. The purpose of this comparative research was to better understand what constitutes the collective ability, or community capacity, these places have for fulfilling their functions as biosphere reserves. Community capacity is the collective mobilization of resources (ecological, economic/built, human and social capitals) for a specified goal. A mixed methods approach was taken. Self-assessments, both qualitative and quantitative, were used to determine community capacity in focus groups with biosphere reserve management, residents, and youth (grades 9-12). The results were compared to a statistics-based assessment of socioeconomic well-being. Semi-structured interviews for a related research project provided further insight. This comparative research made theoretical advancements by identifying key constituents of community capacity, including dimensions of the capitals and mobilizers, or factors that motivate people to work for communal benefit. Mobilizers were found to be key drivers of the process of using and building community capacity. Four mobilizer categories were identified: the existence of, and changes to capital resources; individual traits; community consciousness; and, commitment. The practical implications of applying both qualitative and quantitative assessment methods were examined. It was found that there are several ways to conduct the socioeconomic assessment, and that adaptive methodological application is advised in research that attempts to be truly community-basednot just about, but for and with communities. It was found that, while it does not ensure a biosphere reserves success, economic capital plays a key role in activating other resources beyond a time frame of three years, where social capital can be the primary driver for activity. Despite substantial differences politically, socially, and economically, both regions experienced similar challenges that can be largely attributed to a general lack of understanding of the biosphere reserve concept, and a lack of consistent, core funding.
702

Métodos econométricos para la valoración cualitativa y cuantitativa del daño corporal en el seguro del automóvil

Santolino Prieto, Miguel Ángel 05 June 2007 (has links)
DE LA TESIS:La compensación por daños corporales representa más del 60% del coste total de los siniestros en el seguro de responsabilidad civil del automóvil en el mercado español. El continuo encarecimiento de estos siniestros es un hecho que se da en la mayoría de economías desarrolladas. Las causas de este incremento debemos buscarlas en factores económicos, sociales y legales, como son, entre otros, la propensión a demandar de los ciudadanos, la evolución de los gastos médicos, el nivel de los sueldos, la inflación, así como la visión de la sociedad sobre qué y cómo se debe indemnizar, reflejado en la legislación vigente en el país. Como señala Bell (2006), el aparente descenso en la rentabilidad del seguro de Responsabilidad Civil (RC) hace que las entidades aseguradoras se enfrenten a nuevos retos si desean que continúe siendo un ramo atractivo, como, por ejemplo, una mayor disciplina en la elección y definición de los riesgos que la compañía se compromete a asegurar y, una vez ha ocurrido el siniestro, una correcta tramitación para un mayor control del coste.En el presente trabajo analizamos los factores que influyen en el coste de los siniestros por daños corporales durante su tramitación dentro de la compañía aseguradora, y planteamos medidas concretas de intervención. Cabe considerar que en la práctica, en la mayoría de los casos, las compañías aseguradoras a la hora de calcular las provisiones, o efectuar una oferta en el proceso de negociación, o decidir si investigar o no un siniestro de daños corporales, utilizan como herramienta principal de análisis los informes médicos periciales que han realizado a la víctima durante el período de recuperación. El estudio de las divergencias entre la gravedad otorgada en las sentencias judiciales y la considerada por los médicos peritos en sus informes, y las consecuencias que estas discrepancias tienen sobre el cálculo de las reservas, así como el proponer métodos econométricos alternativos para el cómputo de la provisión económica y para la estimación de la cuantía máxima de negociación del siniestro (para su compensación económica por vía amistosa), es el principal objetivo del presente trabajo.La tesis se estructura fundamentalmente en dos partes: en la primera, nos centramos en el cálculo de las reservas RBNS, y en la segunda, proponemos diferentes mecanismos estadísticos que ayuden a las compañías en el proceso de negociación de la indemnización con la parte contraria. En cuanto a la estimación de las reservas, en primer lugar identificamos las diferentes etapas por las que transcurre un siniestro hasta su liquidación. Para el cálculo de las provisiones, utilizamos un modelo secuencial o por etapas, es decir, un modelo que tenga en cuenta que la información disponible sobre el siniestro se va ampliando gradualmente a lo largo de su vida. Puesto que, por otro lado, las principales discrepancias entre los informes médicos y la sentencia judicial surgen respecto al nivel de gravedad padecido por la víctima (y sabiendo que, estadísticamente, la severidad de una lesión normalmente se trata como una variable categórica ordenada), planteamos ajustar un modelo estadístico de variable dependiente cualitativa para explicarla. En concreto, proponemos estimar un modelo secuencial ordenado de elección múltiple. Esta metodología tiene en cuenta la clasificación final para cada siniestro (gravedad concedida en la sentencia) y puede incluirse dentro de la metodología de estimación estadística individual definida por Taylor y Campbell (2002). En comparación con la estimación directa del coste, esta modelización permite analizar una variable, la gravedad de la lesión, que es más estable a lo largo del tiempo (la valoración económica se ve afectada por la inflación, coste de los servicios médicos, etc.). Al ser un modelo secuencial, incorpora la información en el mismo momento que la compañía la obtiene. Al final del ejercicio económico, la compañía aseguradora provisiona los siniestros pendientes de liquidación en función de la gravedad esperada de la víctima en ese momento, asignándole, por ejemplo, el coste medio de la categoría estimada.En la segunda parte del trabajo, nos situamos en el momento inmediatamente anterior a la valoración económica final del siniestro, es decir, cuando la víctima está ya completamente recuperada (con o sin secuelas), y la compañía aseguradora dispone de la totalidad de información sobre la gravedad de las lesiones. En ese momento, el asegurador debe decidir negociar con la parte contraria la indemnización o ir a juicio. Concretamente, nos formulamos la siguiente pregunta: ¿cuánto debe ofrecer como máximo la compañía aseguradora al demandante para evitar el (probablemente, largo y costoso) proceso judicial? Puesto que disponemos de una base de datos de siniestros con daños corporales cuya indemnización fue concedida mediante sentencia judicial, planteamos que el coste estimado puede ser considerado como el límite máximo de negociación, por encima del cual, la compañía debería preferir ir a juicio. Por lo tanto, para responder a la pregunta formulada, proponemos estimar el coste final de la indemnización utilizando toda la información disponible del siniestro antes de su valoración. En particular, sugerimos un modelo log-lineal mixto que tenga en cuenta la potencial heterocedasticidad y correlación entre los datos (como consecuencia de que en la valoración pueden existir o no informes forenses, y de que diferentes víctimas pueden ser valoradas en una misma sentencia). Debido a la estructura de nuestra muestra, utilizamos inferencia generalizada (Tsui y Weerahandi, 1989) para contrastar los resultados obtenidos.En cuanto a la tercera posible línea de investigación, la cuantificación del fraude en los siniestros por daños corporales, no ha sido tratada en esta tesis por no disponerse en la base de datos de indicadores que confirmasen sospecha de comportamientos deshonestos por parte de los demandantes.Esta tesis se estructura en ocho capítulos, el primero de los cuales es una introducción genérica sobre el tema. En el capítulo 2 presentamos un resumen de los principales antecedentes sobre el estudio del daño corporal en los accidentes de tráfico. En el capítulo tercero, se detalla el sistema de valoración legal vigente en España (el conocido como baremó), y se compara con otros mecanismos de valoración del daño corporal europeos. En el cuarto capítulo se describe la base de datos utilizada en la aplicación empírica. En el capítulo quinto se expone la metodología propuesta para el cálculo de las reservas por siniestros pendientes de liquidación y se ilustra con un ejemplo práctico. Posteriormente en el capítulo sexto se lleva a cabo la estimación del límite máximo de negociación económica mediante la especificación de modelos mixtos. En el capítulo séptimo se presenta el cálculo del intervalo de confianza de la varianza del efecto aleatorio con inferencia generalizada y finalmente, en el último capítulo, se describen las principales conclusiones del trabajo realizado y se detallan las líneas futuras de investigación.
703

Challenges and Opportunities Facing Local Governance Agents in Advancing an Ecosystem Approach to Conceptualizing and Governing Community Health in Norfolk County, Ontario

Edge, Sara January 2007 (has links)
This research focuses on the challenges and opportunities facing local governance agents in advancing an ecosystem approach to conceptualizing and governing community health in Norfolk County, Ontario. Norfolk County is a rural, agriculturally-based community dependent upon tobacco production. This industry has collapsed, triggering widespread socioeconomic impacts and community health pressures. The government is searching for alternative modes of economic development and tensions are high with respect to the direction and nature of these developments. Some citizens are concerned about the security of their rural livelihoods. Others are concerned about ecological integrity. Still others are convinced of the need for aggressive economic growth. Local decision-makers are struggling to meet all of these requirements. An ecosystem approach views health as part of the broader socio-ecological system, recognizing that health outcomes are by-products of complex biophysical, social, political and economic system interactions at nested spatial and temporal scales. The approach contrasts with conventional health models, which tend to be reactionary, narrowly focused, and short-sighted. Such models are typical of the hierarchical, technocratic nature of public administration which renders decision-making structures and processes ill equipped to deal with complex problems. More systemic, integrated, participatory and collaborative approaches to decision-making are needed in order to better address the complexities involved in facilitating healthy and sustainable community development. Additionally, governance agents must also be able to embrace and navigate these evolving approaches to health conceptualization and governance. An investigation into Norfolk County grounds this analysis by revealing the challenges and opportunities facing local governance agents in advancing an ecosystem approach. The case study research effectively tests the utility and feasibility of the ecosystem approach through a qualitative analysis. The research contributes criteria required for advancing an ecosystem approach to community health governance and practice and empirically tests them within the context of Norfolk County.
704

The Value and Risk Implications of Grid Expansion Investments

Dockner, Engelbert J., Kucsera, Denes, Rammerstorfer, Margarethe 30 September 2010 (has links) (PDF)
In this article, we look at a model with (independent) system operator who faces stochastic but growing transmission demand and a penalty if frequency is not balanced. In this set up, we derive an optimal grid expansion investment strategy and analyze its value and risk implications. It turns out that the firm value is strictly concave in the level of transmission demand. Firm value, however, increases with optimal investment for any level of demand. Moreover, firm risk is decreasing in the level of demand and higher when the firm has an investment option. The risk increase corresponds to the exercise of the call option and is stronger, the closer the firm approaches its exercise trigger. (author's abstract) / Series: Working Papers / Research Institute for Regulatory Economics
705

Challenges and Opportunities Facing Local Governance Agents in Advancing an Ecosystem Approach to Conceptualizing and Governing Community Health in Norfolk County, Ontario

Edge, Sara January 2007 (has links)
This research focuses on the challenges and opportunities facing local governance agents in advancing an ecosystem approach to conceptualizing and governing community health in Norfolk County, Ontario. Norfolk County is a rural, agriculturally-based community dependent upon tobacco production. This industry has collapsed, triggering widespread socioeconomic impacts and community health pressures. The government is searching for alternative modes of economic development and tensions are high with respect to the direction and nature of these developments. Some citizens are concerned about the security of their rural livelihoods. Others are concerned about ecological integrity. Still others are convinced of the need for aggressive economic growth. Local decision-makers are struggling to meet all of these requirements. An ecosystem approach views health as part of the broader socio-ecological system, recognizing that health outcomes are by-products of complex biophysical, social, political and economic system interactions at nested spatial and temporal scales. The approach contrasts with conventional health models, which tend to be reactionary, narrowly focused, and short-sighted. Such models are typical of the hierarchical, technocratic nature of public administration which renders decision-making structures and processes ill equipped to deal with complex problems. More systemic, integrated, participatory and collaborative approaches to decision-making are needed in order to better address the complexities involved in facilitating healthy and sustainable community development. Additionally, governance agents must also be able to embrace and navigate these evolving approaches to health conceptualization and governance. An investigation into Norfolk County grounds this analysis by revealing the challenges and opportunities facing local governance agents in advancing an ecosystem approach. The case study research effectively tests the utility and feasibility of the ecosystem approach through a qualitative analysis. The research contributes criteria required for advancing an ecosystem approach to community health governance and practice and empirically tests them within the context of Norfolk County.
706

"All the Crises Reached a Concerted Crescendo" - The Arab Oil Embargo and Why the United States Was Unprepared for It

Chilcote, Jonathan D. 01 December 2009 (has links)
During the 2008 spike in oil prices, oil companies and government officials were brought under close scrutiny as many Americans began to question why prices were able to rise so quickly. Americans had become accustomed to living in an economy where cheap oil was the norm, and demanded answers when that situation changed. What most of them did not know is that they were repeating history and mimicking the response to the 1973 oil embargo. Just as in 2008, the United States faced a crisis in 1973 with which it was unprepared to effectively cope. This thesis analyzes the reasons for and consequences of this lack of preparation in 1973 drawing on the writings of major policy makers and leaders of the time, most notably Henry Kissinger, Anwar el-Sadat, and Richard Nixon, Senate hearings testimony, recently declassified government documents detailing plans for U.S. invasion, and contemporary newspapers which recorded public perception. I argue that decades of living with cheaply priced oil, an over reliance on multinational corporations and a lack of understanding of Middle Eastern resentment toward these oil companies, combined with a fundamental misunderstanding of how oil and politics could be linked brought the United States to the ultimate near-decision of invading the Middle East. The 1973 oil embargo brought the United States face-to-face with the consequences of reliance on foreign oil and with the hardships that resulted from it. The United States had relied on oil companies to manage their interests in the Middle East for decades but in 1973 the situation changed forever. I close by considering the ongoing deep ties between the United States and the Middle East that are present still. The same problems that existed in 1973 exist today, and until those are corrected the United States and its economy will be deeply tied to the Middle East and to events in the region.
707

Assessing community capacity for ecosystem management : Clayoquot Sound and Redberry Lake biosphere reserves

Mendis, Sharmalene Ruwanthi 29 October 2004 (has links)
Biosphere reserves are regions that are internationally recognized for their ecological significance and work towards ecosystem management. The concept of community capacity, as developed in the resource management and health promotion literatures, was applied to two such regions that were designated in 2000: Clayoquot Sound and Redberry Lake. The purpose of this comparative research was to better understand what constitutes the collective ability, or community capacity, these places have for fulfilling their functions as biosphere reserves. Community capacity is the collective mobilization of resources (ecological, economic/built, human and social capitals) for a specified goal. A mixed methods approach was taken. Self-assessments, both qualitative and quantitative, were used to determine community capacity in focus groups with biosphere reserve management, residents, and youth (grades 9-12). The results were compared to a statistics-based assessment of socioeconomic well-being. Semi-structured interviews for a related research project provided further insight. This comparative research made theoretical advancements by identifying key constituents of community capacity, including dimensions of the capitals and mobilizers, or factors that motivate people to work for communal benefit. Mobilizers were found to be key drivers of the process of using and building community capacity. Four mobilizer categories were identified: the existence of, and changes to capital resources; individual traits; community consciousness; and, commitment. The practical implications of applying both qualitative and quantitative assessment methods were examined. It was found that there are several ways to conduct the socioeconomic assessment, and that adaptive methodological application is advised in research that attempts to be truly community-basednot just about, but for and with communities. It was found that, while it does not ensure a biosphere reserves success, economic capital plays a key role in activating other resources beyond a time frame of three years, where social capital can be the primary driver for activity. Despite substantial differences politically, socially, and economically, both regions experienced similar challenges that can be largely attributed to a general lack of understanding of the biosphere reserve concept, and a lack of consistent, core funding.
708

Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geese

Traylor, Joshua James 02 July 2010 (has links)
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p> Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p> I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p> Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.
709

Rapid numerical simulation and inversion of nuclear borehole measurements acquired in vertical and deviated wells

Mendoza Chávez, Alberto 10 August 2012 (has links)
The conventional approach for estimation of in-situ porosity is the combined use of neutron and density logs. These nuclear borehole measurements are influenced by fundamental petrophysical, fluid, and geometrical properties of the probed formation including saturating fluids, matrix composition, mud-filtrate invasion and shoulder beds. Advanced interpretation methods that include numerical modeling and inversion are necessary to reduce environmental effects and non-uniqueness in the estimation of porosity. The objective of this dissertation is two-fold: (1) to develop a numerical procedure to rapidly and accurately simulate nuclear borehole measurements, and (2) to simulate nuclear borehole measurements in conjunction with inversion techniques. Of special interest is the case of composite rock formations of sand-shale laminations penetrated by high-angle and horizontal (HA/HZ) wells. In order to quantify shoulder-bed effects on neutron and density borehole measurements, we perform Monte Carlo simulations across formations of various thicknesses and borehole deviation angles with the multiple-particle transport code MCNP. In so doing, we assume dual-detector tool configurations that are analogous to those of commercial neutron and density wireline measuring devices. Simulations indicate significant variations of vertical (axial) resolution of neutron and density measurements acquired in HA/HZ wells. In addition, combined azimuthal- and dip-angle effects can originate biases on porosity estimation and bed boundary detection, which are critical for the assessment of hydrocarbon reserves. To enable inversion and more quantitative integration with other borehole measurements, we develop and successfully test a linear iterative refinement approximation to rapidly simulate neutron, density, and passive gamma-ray borehole measurements. Linear iterative refinement accounts for spatial variations of Monte Carlo-derived flux sensitivity functions (FSFs) used to simulate nuclear measurements acquired in non-homogeneous formations. We use first-order Born approximations to simulate variations of a detector response due to spatial variations of formation energy-dependent cross-section. The method incorporates two- (2D) and three-dimensional (3D) capabilities of FSFs to simulate neutron and density measurements acquired in vertical and HA/HZ wells, respectively. We calculate FSFs for a wide range of formation cross-section variations and for borehole environmental effects to quantify the spatial sensitivity and resolution of neutron and density measurements. Results confirm that the spatial resolution limits of neutron measurements can be significantly influenced by the proximity of layers with large contrasts in porosity. Finally, we implement 2D sector-based inversion of azimuthal logging-while-drilling (LWD) density field measurements with the fast simulation technique. Results indicate that inversion improves the petrophysical interpretation of density measurements acquired in HA/HZ wells. Density images constructed with inversion yield improved porosity-feet estimations compared to standard and enhanced compensation techniques used commercially to post-process mono-sensor densities. / text
710

The vegetation management of the Botsalano Game Reserve in the North West Province, South Africa.

Bosch, Almero Deon. January 2011 (has links)
Thesis (MTech. degree in Nature Conservation)--Tshwane University of Technology, 2011. / The study was conducted on the Botsalano Game Reserve with the support of the North West Tourism and Parks Agency. No formal management plan is available for the game reserve and therefore the need for an ecological management plan and guidelines for the formulation of a vegetation monitoring plan constituted the basis of the study. The objectives of the study were: 1. To classify and map the plant communities of the Botsalano Game Reserve; 2. To provide quantitative data, collected during a formal vegetation classification, for use by the reserve management in terms of current vegetation condition; 3. To ascertain whether a classification of the vegetation on the BGR could be used for the objective placement of vegetation monitoring sites. Monitoring site placement will be based on representation of plant communities, reflecting community and topographical unit utilization and thus stocking rates based on management decisions.

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