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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.
101

Interdependent Mission Impact Assessment of an IoT System with Hypergame-Theoretic Attack-Defense Behavior Modeling

Thukkaraju, Ashrith Reddy 17 November 2023 (has links)
Mission impact assessment (MIA) research has been explored to evaluate the performance and effectiveness of a mission system, such as enterprise networks with organizational missions and military or tactical mission teams with assigned missions. The key components in such mission systems, including assets, services, tasks, vulnerability, attacks, and defenses, are interdependent, and their impacts are interwoven. However, the current state-of-the-art MIA approaches have less studied such interdependencies. In addition, they have not modeled strategic attack-defense interactions under partial observability. In this work, we propose a novel MIA framework that assesses measures of performance (MoP) or measures of effectiveness (MoE) based on the service requirements (e.g., correctness or timeliness) of a given mission system based on full and comprehensive modeling and simulation of the key system components and their interdependencies. Particularly, we model intelligent attack-defense strategy selections based on hypergame theory, which allows considering uncertainty in estimating each player's hypergame expected utility (HEU) for its best strategy selection. As the case study, we consider an Internet-of-Things (IoT)-based mission system aiming to accurately and timely detect an object, given stringent accuracy and time constraints for successful mission completion. Via extensive simulation experiments, we validate the quality of the proposed MIA tool in its inference accuracy of the mission performance under a wide range of different environmental settings hindering the mission performance assessment and attack-defense interactions. Our results prove that the developed MIA framework shows a sufficiently high inference accuracy (e.g., 80%) even with a small portion of the training dataset (e.g., 20-50%). We also found the MIA can better assess the system's mission performance when attackers exhibit clearer patterns to take more strategic actions using hypergame theory. / Master of Science / In our increasingly interconnected world, mission systems play a crucial role, whether in organizational networks or tactical military operations. We often evaluate these systems to ensure they perform effectively, but there's more to it than meets the eye. Imagine an intricate web of resources, tasks, services, assaults, and defenses that are intertwined and have an impact on one another. The strategic interactions of attack and defense in uncertain environments have been majorly ignored by conventional techniques for mission impact assessment (MIA). Our research introduces a new way of thinking about MIA. We've developed a framework that delves deep into the heart of mission systems, considering how each component affects the others. This comprehensive approach considers not just what's happening but also the interplay of actions and reactions. Hypergame theory, a technique that enables us to model intelligent choices in the face of uncertainty, is at the foundation of our approach. Imagine it as a chess game in which players must predict their opponents' moves and adjust their strategies appropriately. In our case study, we used an Internet-of-Things (IoT)-based mission system tasked with timely and accurate object detection to apply this architecture. In this mission system, both cyber attackers, whose aim is to compromise the mission, and cyber defenders, whose aim is to ensure mission success, are present, and they use the proposed hypergame-based decision-making to perform intelligent actions. What did we find? Through extensive simulations, we confirmed the effectiveness of our MIA framework. Even with limited training data, our tool demonstrated a remarkable 80% accuracy in assessing mission performance. Moreover, it excelled when attackers followed discernible patterns, allowing us to predict and respond strategically. In simpler terms, our research provides a valuable tool for evaluating the success of mission systems in our increasingly connected world. It goes beyond surface-level assessments, considering the intricate relationships between system components and the dynamic nature of strategic decision-making. Ultimately, our framework empowers us to ensure mission success in an ever-evolving landscape.
102

Valuing the Environmental Benefits from GM Products Using an Experimental Procedure: Lessons From the United States and the Philippines

Maupin, Jason Derek 15 January 2007 (has links)
This thesis develops an experimental procedure to value the environmental benefits from two pre-production genetically modified (GM) products, MVR tomatoes and Bt eggplant. The procedure explicitly tells subjects the GM nature of the products, and frames the value as an actual donation to the scientific organization pursuing the product research. The procedure is tested in the United States and the Philippines. The tests suggest that United States students give significantly different values than Filipino farmers with Filipino farmers valuing the environmental benefits much higher than United States students. The tests also suggest that slight changes in procedures can significantly affect values. Subjects also use information learned during the experiment to form their valuations. For example, Filipino farmers significantly increase their values as the procedure progresses. / Master of Science
103

Assessing the Benefits of Virginia Tech Agricultural Programs:  Studies in Feeder Cattle Certification and Small Grains Breeding

Garber, Benjamin Fredrick 03 June 2021 (has links)
This thesis consists of two research papers, each of which studies the benefits from a different College of Agriculture and Life Sciences (CALS) program. These analyses provide necessary information to allocate resources efficiently among programs. The first paper studies the Virginia Quality Assured feeder cattle certification program and its effects on feeder cattle prices and profitability. No significant effect on price from VQA certification is found. However, enterprise budgets indicate that VQA cattle allow higher farm profits due to their lower sale weight, which allows for faster turnover and lower prices. The second paper studies the benefits to producers from wheat and barley breeding conducted by Virginia Tech researchers. Variety trial data are combined with acreage estimates constructed from royalty data to estimate gains from replacement of old varieties with new ones. The study finds that the program generated benefits to producers of over $119 million between 2000 and 2018. / Master of Science / This thesis contains two papers that assessed the benefits of two agricultural research and extension programs at Virginia Tech. The first paper studies the Virginia Quality Assured certification program. This program certifies cattle that have been raised following practices that are designed to result in cattle that will grow faster and stay healthier in a feedlot. Statistical analysis of cattle sold through a Virginia telephone auction show that VQA certified cattle do not receive higher prices than uncertified cattle, but the analysis also finds that certified and uncertified cattle have important physical differences, including lighter weights for certified cattle. These lighter weights make it possible for farmers to sell more VQA cattle in a year because they spend less time gaining weight before being sold, giving producers of VQA cattle the opportunity for higher profits per year. The second paper studies the benefits to farmers from wheat and barley breeding by Virginia Tech researchers. Field trials are used to compare the yields of old and new varieties, and acreage estimates are used to show how newer varieties replace older ones in farmers' fields. The study finds that economic benefits to farmers from new varieties released by the program total $119 million from 2000 to 2018.
104

Two Papers Evaluating the Economic Impact of Agricultural Innovation

Nguema, Abigail M. 04 November 2011 (has links)
While extensive research has been carried out to examine the yield growth brought about by innovations in agricultural technology, not enough work has been done to document the economic impacts of these innovations on areas besides yields and income. This study presents two papers which contribute to our understanding of the health and environmental impacts of agricultural innovation, "Expected economic benefits of meeting nutritional needs through biofortified cassava in Nigeria and Kenya," and "Projected farm-level impacts on income of conservation agriculture in the Andean Region." The first paper is motivated by the public health consequences of vitamin and mineral deficiencies, which affect more than two billion people worldwide and can lead to increased incidence of illness, disability, and mortality. Through the use of the disability adjusted life years concept (DALYs), economic surplus analysis, and benefit-cost analysis, the authors determine the economic impact of a staple crop biofortification project. The study finds that biofortified cassava in Nigeria and Kenya is a cost effective means of reducing health problems associated with vitamin A and iron deficiency. The second paper considers the significant livelihood challenges faced by rural communities in the Andes, including poverty, food insecurity, and natural resource constraints. Through the development and implementation of a linear programming model, the study analyzes the economic impact of a conservation agriculture project in central Ecuador, and finds that certain experimental cropping activities designed to decrease soil degradation may contribute to increased incomes for farm households. / Master of Science
105

Persistence and Power: A Study of Native American Peoples in the Sonoran Desert and the Devers-Palo Verde High Voltage Transmission Line

Bean, Lowell John, Vane, Sylvia, Dobyns, Henry F., Martin, M. Kay, Stoffle, Richard W., White, David R. M. 15 September 1978 (has links)
In the late 1970s, Southern California Edison Company proposed the construction of a 500 Kilovolt transmission line from Buckeye, Arizona (just west of Phoenix) to the Devers substation near Banning California. The proposed routes crossed the traditional territory of numerous Native American groups such as the Cahuilla, Chemehuevi Southern Paiutes, Cocopah, Mojave, Maricopa, O’Odham, Quechan, and Yavapai. As required by the National Environmental Policy Act, an environmental impact assessment was conducted to understand potential impacts this project could have on human and natural resources. For the first time since the passage of NEPA, Native American concerns were fully considered. This report presents the findings of the first Native American social impact assessment in the United States. This report presents contemporary Native American values that were pertinent to planning, construction, operation, and maintenance of high voltage generation and transmission facilities. The ethnographic study also considered the following aspects: (a) determine if, where, and in what manner such values were relevant to the Devers Palo Verde study area, (b) define differing levels of significance that Native Americans assigned to geographical points, zones, or issues within the subject study area exhibiting such values, (c) assign appropriate sensitivity ratings to the pertinent points, zones, or issues of significance and rank such points, zones, and issues from highest to lowest, explain what actions might constitute varying degrees, kinds of impact to those points, zones, or issues, and (e) provide recommendations for mitigation of negative impacts to those points, zones, or issues.
106

Allen-Warner Valley Energy System: Western Transmission System Ethnographic and Historical Resources

Bean, Lowell Bean, Evans, Michael J., Hopa, Ngapare K., Massey, Lee Gooding, Rothenberg, Diane, Stoffle, Richard W., Vane, Sylvia Brakke, Weinman-Roberts, Lois, Young, Jackson 15 December 1979 (has links)
This project examined the potential impacts that construction of the Western Transmission System of the Allen-Warner Valley Energy System would have on the ethnographic and historic resources of the Mojave Desert area. The Western Transmission System of the Allen-Warner Valley Energy System project consisted of two 500-kilovolt transmission lines extending from Southern California Edison Company’s Eldorado Substation in southern Nevada westward across the Mojave Desert to Lugo Substation in Victorville, California. The ethnographic component of this study included the identification of culturally affiliated Native American groups and extensive field investigations which focused on ethnohistory and ethnogeography of the study area. The ethnographic study also documented Native American recommendations for mitigation by Southern California Edison Company of potential adverse impacts that the project had on Native American values and resources.
107

Proposta de padronização em avaliação de impactos ambientais /

Sandoval, Maitê de Souza. January 2008 (has links)
Orientador: Leandro Eugenio da Silva Cerri / Banca: Fábio Augusto Gomes de Vieira Reis / Banca: Flávio Henrique Mingante Schlittler / Resumo: A avaliação da significância dos impactos ambientais continua a ser um importante componente crítico ainda mal compreendido da prática da avaliação de impactos ambientais. Este trabalho é um estudo sobre as conclusões de uma revisão bibliográfica sobre a avaliação e comunicação de avaliação do impacto ambiental praticada no Brasil. É dada especial atenção para a importância da utilização de critérios, padrões e métodos de avaliação de impactos ambientais que pretendendo incorporar mais eficiência nos estudos de impacto ambiental. Assim, o objetivo desta pesquisa foi a realização de uma proposta, incluindo o desenvolvimento de procedimentos e aplicar na avaliação de impactos ambientais situações relativas à sua formulação, aplicação e interpretação da significância dos critérios, conclusões e recomendações pertinentes para respeitar o objetivo da avaliação de impacto ambiental que é garantir a viabilidade ambiental das atividades humanas. / Abstract: The evaluation of the significance of environmental impacts remains an important critical yet poorly understood component of environmental impact assessment practice. This work is a study upon the findings of a bibliographic review about the evaluation and communication of environmental impact assessment in Brazil practice. Particular attention is given to the use of significance criteria, thresholds and EIA methodologies intending to incorporate more efficiency of environmental impact statement. Thus, the aim of this research was the accomplishment of a proposal including the development of procedures to apply in EIA issues surrounding the formulation, application and interpretation of significance criteria, conclusions and recommendations relevant to respect the aim of EIA that in provide environmental viability of men activities. / Mestre
108

THE INFLUENCE OF SURFACE MINING ON RUNOFF TIMING AND FLOW PATHWAYS IN ELK VALLEY, BRITISH COLUMBIA

Shatilla, Nadine J. 01 September 2014 (has links)
<p>Surface mining is a common method of accessing coal. In high-elevation environments, vegetation and soils are typically removed prior to the blasting of overburden rock thereby allowing access to mineable ore. The removed waste rock is deposited in adjacent valleys where it may bury existing streams. Previous research, predominantly in Appalachia, has focused on downstream water quality impacts with less focus on how streamflow response and flow pathways are affected by surface mining. This study reports on how surface mining affects streamflow hydrological and chemical responses at the headwater catchment scale in the Elk Valley, British Columbia. A paired catchment approach was utilized between May and October 2012, where a reference catch- ment (Dry Creek - DC) was compared to an impacted catchment (West Line Creek - WLC), whose area is 30% covered by deposited waste rock. Hydrometrically, WLC had considerably lower flows and exhibited a damped, slower response to precipitation events than DC. Dissolved ions were an order of magnitude greater in WLC, with conductivity (SpC) ranging between 400 μS/cm at high flow to 1300 μS/cm at low flow. A strong hysteretic pattern was observed between SpC and flow and with specific ions at WLC, suggesting dilution or changing flowpaths as the season progressed. In contrast, patterns of SpC and flow at DC did not exhibit hysteresis. Major ion hydrochemistry at WLC shows dilution affecting ion concentrations whereas results at DC are consistent with chemostatic behavior. Stable isotopes were more depleted at DC compared with WLC, suggesting different sources and timing of water contributing to streamflow. Future research will work towards a conceptual model of surface mining impacts on catchment scale processes in montane environments through increased understanding of residence time and flowpath distributions at a number of impacted and reference catchments.</p> / Master of Science (MSc)
109

Incorporation of Sustainable Development Concerns in Regulatory Impact Assessments

Ritzka, Martin Stefan January 2016 (has links)
Regulatory Impact Analyses (RIA) are carried out in order to determine how a project or regulation affects the economy, society and environment. Traditionally, RIAs are carried out through cost benefit assessments and by monetizing different variables in order to assist policymakers with their decision. The main disadvantage of it, is that highly relevant social and environmental factors are difficult to quantify, thus providing weak or "incomplete" support to policy-makers in their final decision and enabling long-term consequences. An option to improving RIAs, is by taking into account such factors with the introduction of Sustainable Development (SD) concerns early in the decision making process. This is a trend that has been gaining more momentum and support, especially in OECD and EU members. The shift towards the inclusion of such concerns at a regulatory and legislative level nonetheless still presents itself to be a challenge and has wide room for improvements. On this research, four different countries and the European Union are analyzed and compared, presenting their current RIA practices and how much they take into account sustainability concerns with the intent on showing where can they be improved and better included.
110

O lugar do social na avaliação de impacto ambiental: regulação pública no Brasil, avanços teóricos e desafios para o planejamento regional / The place of the social in the evaluation of environmental impact: public regulation in Brazil, theoretical advances and challenges for regional planning

Carolino, Ariella Kreitlon 07 June 2016 (has links)
A presente pesquisa tomou por objeto de estudo central a dimensão social (mais conhecida como \'componente antrópico\' ou \'componentes do meio socioeconômico\') consubstanciada na prática e no discurso de avaliação de impacto ambiental. Buscou-se analisar as ausências, lacunas, insuficiências, distorções e omissões ativas no trato dessa dimensão social, procurando compreendê-las como indícios da configuração momentânea das fronteiras do \'social\' na regulação ambiental de projetos no Brasil, enquanto construção histórica atravessada por interesses conflitantes entre os envolvidos nas disputas por hegemonia do campo ambiental, sem perder de vista seu diálogo com outros campos do espaço social, como o político e o econômico. Através dessa chave interpretativa, foi possível retomar as origens e características históricas que conformaram os sentidos dominantes de termos como \'meio ambiente\', \'impacto ambiental\' e \'atingido\' na regulação pública e na atividade de avaliação de impacto, subsumindo da equação os impactos e processos sociais relacionados à implantação de grandes projetos. A pesquisa argumenta, nesse sentido, que ao componente social tem sido atribuído um papel marginal, frágil e bastante delimitado espacial e temporalmente, corroborando com críticas históricas a este instrumento de planejamento. Diagnósticos empobrecidos, avaliações que escamoteiam a complexidade de impactos sociais cumulativos, indiretos e de segunda ordem (cujas marcas são o longo prazo, a fluidez das fronteiras espaciais, a imprevisibilidade, a intangibilidade e a dificuldade de valoração monetária) e medidas mitigadoras e compensatórias insuficientes são ilustrados empiricamente pela pesquisa, tomando o estudo de impacto ambiental de um projeto de anel rodoviário recente, situado no Litoral Norte do estado de São Paulo, como matéria-prima principal de análise. Aliado a uma metodologia investigativa, baseada no levantamento de documentos oficiais do processo licenciatório, a pesquisa procurou identificar os meandros, os mecanismos, as operações e os filtros que recolocam o \'social\' como parte subordinada da avaliação de impacto ambiental, dando pouquíssimo relevo a questões fundamentais, como: fluxos migratórios, crescimento demográfico, demanda adicional sobre infraestrutura e serviços urbanos, transformações da paisagem e novas configurações urbanas, mudança de perfil sociocultural e econômico em nível regional, etc. Em paralelo, após extensa revisão bibliográfica nacional e internacional na área de avaliação de impacto social (que serviu de embasamento teórico-conceitual à pesquisa), procurou-se averiguar em que medida as novas formulações discursivas emergentes, tanto no campo ambiental quanto no subcampo profissional da avaliação de impacto, nos últimos trinta anos, têm encontrado ressonância na prática da avaliação de impacto ambiental de projetos, no país - i.e., como têm sido apropriadas por agentes reguladores e consultores técnicos responsáveis pelos EIAs. Por fim, a pesquisa buscou tecer reflexões sobre as potencialidades e limitações inerentes à avaliação de impacto ambiental como instrumento de planejamento regional, integrado, democrático, fundado em princípios de equidade ambiental e no reconhecimento das demandas de grupos sociais atingidos. / The present study has focused on the social dimension (better known as \'anthropic component\' or \'components of the socioeconomic environment\'), based on the practice and discourse of environmental impact assessment. It sought to analyze the absences, gaps, inadequacies, distortions and omissions that are active in the treatment of this social dimension, seeking to understand them as signs of the momentary configuration of the boundaries of the \'social\' in the environmental regulation of projects in Brazil, as a historical construction crossed by interests Conflict between those involved in environmental hegemony disputes, without losing sight of their dialogue with other fields of social space, such as political and economic. Through this interpretive key, it was possible to return to the origins and historical characteristics that conformed the dominant meanings of terms such as \'environment\', \'environmental impact\' and \'reached\' in public regulation and impact assessment activity, subsuming impacts And social processes related to the implementation of large projects. The research argues, in this sense, that the social component has been assigned a marginal, fragile and quite delimited spatial and temporal role, corroborating historical criticism of this planning instrument. Impoverished diagnostics, assessments that eschew the complexity of cumulative, indirect and second-order social impacts (whose long-term marks, fluidity of spatial boundaries, unpredictability, intangibility and difficulty in monetary valuation) and insufficient mitigating and compensatory measures Are empirically illustrated by the survey, taking the environmental impact study of a recent road ring project, located in the North Coast of the state of São Paulo, as the main raw material for analysis. In addition to an investigative methodology, based on the collection of official documents of the licensing process, the research sought to identify the meanders, mechanisms, operations and filters that replace the \'social\' as a subordinate part of the environmental impact assessment, giving very little emphasis to Such as: migration flows, population growth, additional demand on infrastructure and urban services, landscape transformations and new urban configurations, socio-cultural and economic profile change at the regional level, etc. In parallel, after extensive national and international literature review in the area of social impact assessment (which served as a theoretical-conceptual basis for research), it was sought to determine to what extent new emerging discursive formulations, both in the environmental field and in the professional subfield Of the impact assessment over the last thirty years have found resonance in the practice of assessing the environmental impact of projects in the country - ie as they have been appropriated by regulators and technical consultants responsible for EIAs. Finally, the research sought to reflect on the potentialities and limitations inherent to environmental impact assessment as a regional, integrated, democratic planning tool based on principles of environmental equity and the recognition of the demands of affected social groups.

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