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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.
241

Genetic structuring in the thirteen-lined ground squirrel (Spermophilus tridecemlineatus) testing the central/peripheral model and colonization patterns /

Kalkvik, Håkon, M. January 2005 (has links)
Thesis (M.S.)--Ohio University, August, 2005. / Title from PDF t.p. Includes bibliographical references (p. 31-39)
242

Indicadores de qualidade estrutural e trafegabilidade de latossolos e argissolos vermelhos. / Indicators of structural quality and trafficability of hapludox and hapludalf.

Imhoff, Silvia Del Carmen 05 July 2002 (has links)
O solo, além de ser um dos recursos básicos dos ecossistemas naturais e agropecuários, é considerado um recurso finito, frágil e não renovável, razão pela qual a manutenção de sua qualidade tem adquirido grande relevância nas últimas décadas. Diversos indicadores de qualidade física do solo foram avaliados em solos de clima temperado no intuito de desenvolver normas de preparo e trafegabilidade que permitam definir as práticas de manejo mais adequadas e o momento mais oportuno para efetua-las visando conservar o recurso solo. Entretanto, é escassa a informação para solos desenvolvidos sob a influência do clima tropical. Nesse contexto, o objetivo geral desta pesquisa foi avaliar, quantitativamente, diversos indicadores de qualidade física do solo direta e indiretamente relacionados à produtividade das culturas, e desenvolver funções de pedotransferência que permitam estimar esses indicadores a partir de atributos físicos facilmente mensuráveis, para Latossolos e Argissolos Vermelhos. Os objetivos específicos foram: i) avaliar os indicadores da condição estrutural do solo "resistência tênsil dos agregados" e "friabilidade" e, determinar a influência de atributos físicos intrínsecos nesses indicadores; ii) quantificar os indicadores de trafegabilidade "susceptibilidade à compactação", "pressão de preconsolidação" e "compressibilidade" e, determinar a influência da umidade, matéria orgânica, textura e estrutura nesses indicadores; iii) avaliar o indicador de qualidade estrutural "intervalo hídrico ótimo" e o indicador de trafegabilidade "pressão de preconsolidação", relacioná-los e determinar valores de pressões críticas que podem ser aplicados ao solo sem induzir condições restritivas ao crescimento das plantas e compactação adicional do solo; e iv) desenvolver funções de pedotransferência que permitam estimar os indicadores avaliados a partir de atributos do solo facilmente mensuráveis. Os resultados referentes ao objetivo i) indicaram que a resistência tênsil dos agregados foi positivamente relacionada com os teores de silte+argila e matéria orgânica, e que os óxidos de Fe pouco cristalinos foram os constituintes da fração silte+argila que mais influenciaram a resistência dos agregados. Os solos estudados foram muito friáveis, estando a friabilidade relacionada positivamente com o teor de óxidos de Fe cristalinos. Os resultados referentes ao objetivo ii) mostraram que o índice de compressão foi significativamente relacionado com a textura (teor de argila) e estrutura (densidade do solo). A pressão de preconsolidação foi significativamente relacionada com a umidade, densidade do solo e o teor de argila. A compressibilidade do solo foi dependente da densidade do solo. Os resultados referentes ao objetivo iii) indicaram que o intervalo hídrico ótimo e a pressão de preconsolidação foram relacionados com a densidade do solo e a umidade. A partir do intervalo hídrico ótimo foi obtida a densidade do solo crítica para o crescimento das plantas, que foi utilizada para a quantificação de pressões críticas. A pressão crítica para o desenvolvimento das plantas foi negativa e linearmente relacionada com o incremento da umidade. No que se refere ao objetivo iv), foram geradas funções de pedotransferência que permitem estimar os indicadores avaliados a partir de atributos do solo facilmente mensuráveis. / The soil, besides being one of the basic resources of the natural and agricultural ecosystems, has been considered a finite, fragile and no renewable resource. For this reason the maintenance of its quality has been acquiring great relevance in the last decades. Several soil physical quality indicators have been used with the intention of developing guides of workability and trafficability that allow to define the more appropriate management practices and the most opportune moment for applying them in view to conserve the soil quality. However, it is scarce the information for soils developed under the influence of tropical climates. In this context, the general objective of this research was to evaluate, quantitatively, several indicators of soil physical quality that are directly and indirectly related to the productivity of the cultures, and to develop pedotransfer functions to make possible to estimate those indicators using easily measurable soil attributes for Hapludox and Hapludalf. The specific objectives were: i) to evaluate the workability indicators "tensile strength of the aggregates" and "friability" and, to determine the influence of the soil intrinsic properties on those indicators; ii) to quantify the trafficability indicators "susceptibility to compaction", "preconsolidation pressure" and "compressibility", and to determine the influence of soil water content, organic matter, texture, and structure on those indicators; iii) to evaluate the structural quality indicator "least limiting water range" and the trafficability indicator "preconsolidation pressure", to relate them, and to determine values of critical pressures that can be applied to the soil without inducing restrictive conditions to plant growth and additional soil compaction; and iv) to develop pedotransfer functions to estimate the measured indicators using easily measurable soil attributes. The results related the objective i) indicated that soil tensile strength was positively related to clay+silt content and organic matter, and that poorly crystalline iron oxides were the constituent of clay+silt fractions that most contributed to soil tensile strength. Results also indicated that the soils were highly friable, with the crystalline iron forms being positively related to soil friability. The results related to the objective ii) showed that the compression index was significantly related to soil texture and soil bulk density. The preconsolidation pressure was significantly related to soil water content, soil texture (clay content), and bulk density. The soil compressibility was related to bulk density. The results related to the objective iii) showed that least limiting water range and preconsolidation pressure were related to soil bulk density and soil water content. The least limiting water range was used to obtain the soil critic bulk density for the plants growth, which in turn was used to quantify the soil critical pressures. The soil critical pressure for plant development was negative and linearly related to the increase of water content. Pedotransfer functions that make possible to estimate the evaluated indicators from easily measurable soil attributes were generated in answer to the objective iv).
243

Indicadores de qualidade estrutural e trafegabilidade de latossolos e argissolos vermelhos. / Indicators of structural quality and trafficability of hapludox and hapludalf.

Silvia Del Carmen Imhoff 05 July 2002 (has links)
O solo, além de ser um dos recursos básicos dos ecossistemas naturais e agropecuários, é considerado um recurso finito, frágil e não renovável, razão pela qual a manutenção de sua qualidade tem adquirido grande relevância nas últimas décadas. Diversos indicadores de qualidade física do solo foram avaliados em solos de clima temperado no intuito de desenvolver normas de preparo e trafegabilidade que permitam definir as práticas de manejo mais adequadas e o momento mais oportuno para efetua-las visando conservar o recurso solo. Entretanto, é escassa a informação para solos desenvolvidos sob a influência do clima tropical. Nesse contexto, o objetivo geral desta pesquisa foi avaliar, quantitativamente, diversos indicadores de qualidade física do solo direta e indiretamente relacionados à produtividade das culturas, e desenvolver funções de pedotransferência que permitam estimar esses indicadores a partir de atributos físicos facilmente mensuráveis, para Latossolos e Argissolos Vermelhos. Os objetivos específicos foram: i) avaliar os indicadores da condição estrutural do solo "resistência tênsil dos agregados" e "friabilidade" e, determinar a influência de atributos físicos intrínsecos nesses indicadores; ii) quantificar os indicadores de trafegabilidade "susceptibilidade à compactação", "pressão de preconsolidação" e "compressibilidade" e, determinar a influência da umidade, matéria orgânica, textura e estrutura nesses indicadores; iii) avaliar o indicador de qualidade estrutural "intervalo hídrico ótimo" e o indicador de trafegabilidade "pressão de preconsolidação", relacioná-los e determinar valores de pressões críticas que podem ser aplicados ao solo sem induzir condições restritivas ao crescimento das plantas e compactação adicional do solo; e iv) desenvolver funções de pedotransferência que permitam estimar os indicadores avaliados a partir de atributos do solo facilmente mensuráveis. Os resultados referentes ao objetivo i) indicaram que a resistência tênsil dos agregados foi positivamente relacionada com os teores de silte+argila e matéria orgânica, e que os óxidos de Fe pouco cristalinos foram os constituintes da fração silte+argila que mais influenciaram a resistência dos agregados. Os solos estudados foram muito friáveis, estando a friabilidade relacionada positivamente com o teor de óxidos de Fe cristalinos. Os resultados referentes ao objetivo ii) mostraram que o índice de compressão foi significativamente relacionado com a textura (teor de argila) e estrutura (densidade do solo). A pressão de preconsolidação foi significativamente relacionada com a umidade, densidade do solo e o teor de argila. A compressibilidade do solo foi dependente da densidade do solo. Os resultados referentes ao objetivo iii) indicaram que o intervalo hídrico ótimo e a pressão de preconsolidação foram relacionados com a densidade do solo e a umidade. A partir do intervalo hídrico ótimo foi obtida a densidade do solo crítica para o crescimento das plantas, que foi utilizada para a quantificação de pressões críticas. A pressão crítica para o desenvolvimento das plantas foi negativa e linearmente relacionada com o incremento da umidade. No que se refere ao objetivo iv), foram geradas funções de pedotransferência que permitem estimar os indicadores avaliados a partir de atributos do solo facilmente mensuráveis. / The soil, besides being one of the basic resources of the natural and agricultural ecosystems, has been considered a finite, fragile and no renewable resource. For this reason the maintenance of its quality has been acquiring great relevance in the last decades. Several soil physical quality indicators have been used with the intention of developing guides of workability and trafficability that allow to define the more appropriate management practices and the most opportune moment for applying them in view to conserve the soil quality. However, it is scarce the information for soils developed under the influence of tropical climates. In this context, the general objective of this research was to evaluate, quantitatively, several indicators of soil physical quality that are directly and indirectly related to the productivity of the cultures, and to develop pedotransfer functions to make possible to estimate those indicators using easily measurable soil attributes for Hapludox and Hapludalf. The specific objectives were: i) to evaluate the workability indicators "tensile strength of the aggregates" and "friability" and, to determine the influence of the soil intrinsic properties on those indicators; ii) to quantify the trafficability indicators "susceptibility to compaction", "preconsolidation pressure" and "compressibility", and to determine the influence of soil water content, organic matter, texture, and structure on those indicators; iii) to evaluate the structural quality indicator "least limiting water range" and the trafficability indicator "preconsolidation pressure", to relate them, and to determine values of critical pressures that can be applied to the soil without inducing restrictive conditions to plant growth and additional soil compaction; and iv) to develop pedotransfer functions to estimate the measured indicators using easily measurable soil attributes. The results related the objective i) indicated that soil tensile strength was positively related to clay+silt content and organic matter, and that poorly crystalline iron oxides were the constituent of clay+silt fractions that most contributed to soil tensile strength. Results also indicated that the soils were highly friable, with the crystalline iron forms being positively related to soil friability. The results related to the objective ii) showed that the compression index was significantly related to soil texture and soil bulk density. The preconsolidation pressure was significantly related to soil water content, soil texture (clay content), and bulk density. The soil compressibility was related to bulk density. The results related to the objective iii) showed that least limiting water range and preconsolidation pressure were related to soil bulk density and soil water content. The least limiting water range was used to obtain the soil critic bulk density for the plants growth, which in turn was used to quantify the soil critical pressures. The soil critical pressure for plant development was negative and linearly related to the increase of water content. Pedotransfer functions that make possible to estimate the evaluated indicators from easily measurable soil attributes were generated in answer to the objective iv).
244

A study of attitudes pertaining to the Richardson's ground squirrel

Kincaid, Adela Tesarek, University of Lethbridge. Faculty of Arts and Science January 2003 (has links)
Ecologically, Richardson's ground squirrels comprise and uphold a major part of the prairie ecosystem. However, from a soceital perspective, many residents of the prairies view them as nothing more than 'pests' in need of eradication. The focus of this research is on attitudes, knowledge, and public support for specific management strategies in relation to Richardson's ground squirrels. Measuring human attitudes about wildlife is a growing field of study that can provide important information to resource management personnel. Surveys were administered to rural residents, urban residents, and grade 12 high school students residing in Lethbridge, Alberta or within a 60-km radius of the city. Urban people had a significantly more positive overall attitude score than rural people. Rural people had a significantly higher knowledge score than urban residents. Rural people supported lethal management practices in all areas listed whereas urban people more often supported alternative management practices such as capture and relocation or the introduction of predators. Both urban and rural people believed that overpopulation of Richardson's ground squirrels and the depletion of crops caused by Richardson's ground squirrels were serious problems. Overall, rural people perceived problems caused by Richardson's ground squirells to be more serious problems than did urban residents. Results provide information for decision-makers and highlight areas where education might focus. In addition, a baseline of existing attitudes toward Richardson's ground squirrels is created against which future change in attitudes or knowledge can be measured. / x, 191 leaves : ill. (some col.) ; 29 cm.
245

New Ground Motion Prediction Equations for Saudi Arabia and their Application to Probabilistic Seismic Hazard Analysis / サウジアラビアにおける地震動予測式の構築と確率論的地震動予測への適用

Kiuchi, Ryota 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22259号 / 理博第4573号 / 新制||理||1657(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 James Mori, 教授 久家 慶子, 教授 岩田 知孝 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
246

TRENCH CAPPING WITH REINFORCED SOIL-CEMENT.

Armstrong, Glenn Irons. January 1984 (has links)
No description available.
247

AATIA & CAIS GROUND SUPPORT

Caldera, M. C., Paz, Marco 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Advanced Airborne Test Instrumentation System (AATIS) was developed by the Air Force to satisfy its flight-test mission needs through the 1990s. The Common Airborne Instrumentation System (CAIS) is a tri-service development aimed at providing a common airborne data acquisition system for all DoD flight-test programs into the next century. Both AATIS and CAIS include ground support equipment which performs the primary functions of documenting the instrumentation system, generating and loading the telemetry data formats, and performing instrumentation system diagnostics. The AATIS and CAIS ground systems will each support both the AATIS and the CAIS airborne systems. The AATIS ground system also supports the older ATIS airborne systems. The approach taken by the two ground support systems is similar but the scope of functionality is larger in the AATIS ground system because it needed to respond to the more extensive ground support requirements of the Air Force users. This paper provides a brief description of both ground systems and discusses the issues of commonality and interoperability.
248

Application of IP Multicasting to the NASA Communications Command and Telemetry Ground Network

Spinolo, M. Chris 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / The NASA Communications (Nascom) Division has been directed to deploy Internet Protocol (IP) based technology for the ground segments of all present and future spaceflight telemetry networks. The Nascom network supports all NASA spaceflight telemetry, command and status requirements, from sounding rockets and balloons to the Hubble Space Telescope and the Space Shuttle. This paper discusses the challenges of transitioning a 35 year old, custom engineered, worldwide legacy telemetry network to IP, and the resulting, new NASA IP Operational Network for ground transport of spacecraft telemetry and command.
249

ANALYSIS ON THE COVERAGE CHARACTERISTICS OF GLONASS CONSTELLATION

Hui, Liu, Qishan, Zhang 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The coverage characteristics of the GLONASS constellation is analyzed. The almanac data of GLONASS navigation message are used in the computation according to the operation of the satellites. The ground traces of the GLONASS satellites are plotted. And the probability of visible satellite number is calculated under different latitude conditions. The results are analyzed to give descriptions of the GLONASS constellation. And they are compared with those of GPS's. The conclusion is verified that GLONASS constellation provides better coverage at high latitude.
250

Ground source heat pump system models in an integrated building and ground energy simulation environment

Garber, Denis January 2014 (has links)
No description available.

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