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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.
31

An agent-based forest sector modeling approach to analyzing the economic effects of natural disturbances

Schwab, Olaf Sebastian 05 1900 (has links)
This dissertation describes the development of CAMBIUM, an agent-based forest sector model for large-scale strategic analysis. This model is designed as a decision support tool for assessing the effect that changes in forest product demand and resource inventories can have on the structure and economic viability of the forest sector. CAMBIUM complements existing forest sector models by modeling aggregate product supply as an emergent property of individual companies’ production decisions and stand-level ecological processes. Modeling the forest products sector as a group of interacting autonomous agents makes it possible to introduce production capacity dynamics and the potential for mill insolvencies as factors in modeling the effects of market and forest inventory based disturbances. This thesis contains four main manuscripts. In the first manuscript I develop and test a dispersal algorithm that projects aggregated forest inventory information onto a lattice grid. This method can be used to generate ecologically and statistically consistent datasets where high-quality spatial inventory data is otherwise unavailable. The second manuscript utilizes this dataset in developing a provincial-level resource dynamics model for assessing the timber supply effects of introducing weevil-resistant spruce. This model employs a stand-level approach to simulating weevil infestation and associated merchantable volume losses. Provincial-level impacts are determined by simulating harvest activities over a 350 year time horizon. In the third manuscript I shift the focus to interactions between forest companies. I analyze the effects of strategic decisions on sector structure by developing CAMBIUM as an agent-based model of competition and industry structure evolution. The forest sector is modeled as a group of autonomous, interacting agents that evolve and compete within the limitations posed by resource inventories and product demand. In the final manuscript I calibrate CAMBIUM to current conditions in the British Columbia forest sector. Industry agents compete for roundwood inputs, as well as for profits in finished product markets for pulp, panel products, and lumber. To test the relevance and utility of this model, CAMBIUM is used to quantify the cumulative impacts of a market downturn for forest products and mountain pine beetle induced timber supply fluctuations on the structure of the forest sector.
32

A Decision Support Tool For Conceptual Site Model Development At Contaminated Sites

Buyuker, Beril 01 September 2009 (has links) (PDF)
A conceptual site model (CSM) is simply a description of the environmental conditions at a contaminated site and surrounding area, which provides all interested parties with a vision of the site. CSM mainly identifies the source-pathway&amp / #8208 / receptor linkage to guide for effective site characterization, risk assessment and remedial investigations. Development of CSM is complicated because it is &lsquo / case specific&rsquo / and there is no single route to follow during decision making concerning the contaminated site. Moreover, type and extent of information needed varies according to size and level of contamination and site heterogeneity. The objective of this study is to develop a decision support tool that guides the site assessors during identification of possible decision routes that can be encountered / the procedure to be followed / and the information and data to be collected at each stage. This tool also introduces interactions between CSM andsampling strategies designed for various purposes. Developed decision support tool adapts to each specific contaminated site. Furthermore, a detailed review of sampling strategies is presented as a guidance for site assessors. The decision support tool is equipped with standardized tools used for CSM development, i.e. information/data collection forms, illustrative tools and exposure pathway diagram. Information on site, geology, hydrogeology, contamination source, contaminants and receptors is collected via CSM form. Illustrative tools may vary from very simple site sketches to very complex 3D drawings depending on the needs of the specific contamination cases. Exposure pathway diagram (EPD) is used to identify all transport mechanisms and potential exposure pathways. EPD is embedded into a user&amp / #8208 / friendly decision assistance tool based on Microsoft Excel and Visual Basic for Applications. The applicability and utility of the decision support tool was tested using two case studies. Case study applications indicated that the developed methodology satisfies the objectives aimed in this study.
33

An agent-based forest sector modeling approach to analyzing the economic effects of natural disturbances

Schwab, Olaf Sebastian 05 1900 (has links)
This dissertation describes the development of CAMBIUM, an agent-based forest sector model for large-scale strategic analysis. This model is designed as a decision support tool for assessing the effect that changes in forest product demand and resource inventories can have on the structure and economic viability of the forest sector. CAMBIUM complements existing forest sector models by modeling aggregate product supply as an emergent property of individual companies’ production decisions and stand-level ecological processes. Modeling the forest products sector as a group of interacting autonomous agents makes it possible to introduce production capacity dynamics and the potential for mill insolvencies as factors in modeling the effects of market and forest inventory based disturbances. This thesis contains four main manuscripts. In the first manuscript I develop and test a dispersal algorithm that projects aggregated forest inventory information onto a lattice grid. This method can be used to generate ecologically and statistically consistent datasets where high-quality spatial inventory data is otherwise unavailable. The second manuscript utilizes this dataset in developing a provincial-level resource dynamics model for assessing the timber supply effects of introducing weevil-resistant spruce. This model employs a stand-level approach to simulating weevil infestation and associated merchantable volume losses. Provincial-level impacts are determined by simulating harvest activities over a 350 year time horizon. In the third manuscript I shift the focus to interactions between forest companies. I analyze the effects of strategic decisions on sector structure by developing CAMBIUM as an agent-based model of competition and industry structure evolution. The forest sector is modeled as a group of autonomous, interacting agents that evolve and compete within the limitations posed by resource inventories and product demand. In the final manuscript I calibrate CAMBIUM to current conditions in the British Columbia forest sector. Industry agents compete for roundwood inputs, as well as for profits in finished product markets for pulp, panel products, and lumber. To test the relevance and utility of this model, CAMBIUM is used to quantify the cumulative impacts of a market downturn for forest products and mountain pine beetle induced timber supply fluctuations on the structure of the forest sector.
34

Design and Case Study Application of a Participatory Decision-making Support Tool for Appropriate Safe Water Systems Development in Marginalized Communities of the Global South

Ali, Syed Imran 18 June 2012 (has links)
This dissertation presents the design and case study application of a participatory decision-making support tool for appropriate safe water systems development in marginalized low-income communities of the global South. The tool focuses on the resolution of two key design decisions: 1) selecting the appropriate level of application (i.e. household or community level) for a safe water system; and 2) selecting an appropriate water treatment technology (or technologies). The tool breaks the process down into four stages. First are pre-implementation steps which develop a contextualized, baseline understanding of the local community. Second is community-based field research, including focus groups and key informant/informal interviews, to investigate the two key design questions by exploring local preferences, capacities, and circumstances with community-members, government officers, NGO workers, and other stakeholders. Third are analytical steps to integrate information from baseline, informal, and primary research to generate recommendations on the two key design questions. This includes a comparative analysis of household and community level systems; a technology feasibility flowchart; performance assessments of technological alternatives with respect to appropriate technology criteria; and a multi-factor analysis to integrate information from the preceding analytical steps. Fourth are community forums in which further participatory action and research is planned on the basis of the recommendations emerging from the tool. Through these steps, the decision-making support tool guides implementing organizations through the stages of safe water systems design and planning in a manner that centres local people in the process. The tool weaves together several theoretical and methodological strands including humanitarian engineering, post-normal science, appropriate technology, participatory development, grounded theory, engineering decision-making, and water treatment engineering. The case study application of the decision-making support tool was conducted in a marginalized peri-urban community called Mylai Balaji Nagar in Chennai, India. This indicated that a household level approach is more appropriate for the case study community and that the TATA Swach filter, alum coagulation with chlorination, or boiling, in order of decreasing suitability, may be appropriate technologies for household application in the case study community. / Degree: Doctor of Philosophy Department: School of Engineering Advisor: Hall, Kevin / International Development Research Centre (IDRC)
35

ASSESSMENT OF THE TECHNICAL AND ECONOMIC POTENTIAL OF AUTOMATED ESTRUS DETECTION TECHNOLOGIES FOR DAIRY CATTLE

Dolecheck, Karmella Ann 01 January 2015 (has links)
Poor estrus detection can limit the reproductive performance of a dairy herd. One objective of this research was to evaluate an alternative method to traditional estrus detection in the form of automated monitoring technologies. To accomplish this, the first study considered the ability of automatically monitored parameters (activity, number of steps, lying bouts, lying time, feeding time, rumination time, and temperature) to detect estrus. A second study compared automated activity monitoring to timed artificial insemination as reproductive management strategies on commercial herds. The other objective of this research was to evaluate the economic potential of automated estrus detection technologies. This was accomplished by creating and evaluating a farm specific decision support tool to determine the net present value of adopting an automated estrus detection technology.
36

A decision support tool for optimising the use of offsite technologies in housebuilding

Pan, Wei January 2006 (has links)
In recent years the industry has been exhorted to increase its use of offsite technologies, or 'Modem Methods of Construction', in order to address the under-supply and poor build quality of housing. Despite the well-rehearsed benefits of such technologies, the take-up within the industry has been slow. Many studies have attempted to scrutinise the barriers and seek solutions, but the perspectives and practices of housebuilders of using offsite remain unclear. This is significant given that housebuilders contribute nearly 90% to the housing unit completions by the industry overall. This thesis aims to provide a strategy for optimising the use of offsite in housebuilding by investigating UK housebuilders' views on, and utilisations of, such technologies. This has been achieved through a combination of a survey of the top 100 firms, a one and-half-year case study of a large housebuilding organisation, and a series of validation interviews and group exercises, within the existing theoretical framework. The thesis reveals that the current low level of offsite usage in large housebuilders was likely to increase given the pressures to improve quality, time, cost, productivity and health & safety. However, a wider take-up was inhibited by perceived higher capital costs, interfacing problems, long lead-in time, delayed planning process and current manufacturing capacity. For addressing this a framework of strategies is presented, surrounding changing the industry's perceptions, improving procurement, providing better cost data, tackling planning and regulations, encouraging political levers, and providing guidance on decision-making and offsite integration. The thesis then contextualises these findings into the organisational and project contexts, examining the historical and current offsite practices within the general housebuilding business. It reveals that housebuilders primarily aspired to improve business efficiency and mitigate financial risks through the use of offsite despite a complicated agenda for such usage. For using offsite housebuilders developed strategies centred on process, procurement, learning & benchmarking, and training. However, the current heuristic approach to decision-making, coupled with the lack of knowledge of build system selection (BSS) for housebuilding, prevents the benefits from offsite being fully realised. A robust, structured and transparent decision support tool for BSS is developed, transferring knowledge in operational and construction management research to the housebuilding context. It provides an improved decision-making process and databases for system selection. Both the process and data were validated within the wider industry and academic domain, by which the tool was claimed as an effective mechanism for optimising the use of offsite and enhancing organisational learning. The thesis contributes to a better theoretical understanding of offsite and provides strategies for its increased take-up in housebuilding. This helps housebuilding organisations to achieve long-term profitability, but also contributes to addressing the current under-supply of housing. The thesis also contributes to knowledge of decisionmaking and construction management research. This has an implication for wider organisational and decision theory.
37

Tomada de decisão de investimento através de método multicritério para fins de planejamento da expansão da distribuição

Pressi, Roberto André January 2017 (has links)
O planejamento da expansão do sistema elétrico é uma das principais atividades em uma distribuidora de energia elétrica, representando uma grande parcela dos investimentos realizados pelas distribuidoras para atender a demanda dos consumidores e os critérios estabelecidos pela agência reguladora (ANEEL). As empresas buscam o apoio de métodos multicritério no processo decisório de investimento, para otimizar e priorizar, com o intuito de obterem êxito na elaboração de um plano de obras que contemple aspectos técnicos e econômicos. A revisão sistêmica da literatura foi realizada em trabalhos de relevância para o tema em estudo, com auxílio de cinco bases de dados. O referencial teórico, que totaliza 52 publicações, apresenta conceitos teóricos sobre o processo decisório através de métodos multicritério de apoio à decisão, bem como exemplifica, através de aplicações práticas como os métodos estão sendo utilizados na área de energia. Com base nesta revisão foi possível estruturar a aplicação da Teoria da Utilidade Multiatributo (MAUT) em um processo decisório de investimento para fins de planejamento da expansão do sistema de distribuição em uma concessionária distribuidora de energia elétrica. Com a aplicação do método fica evidenciada a importância de um procedimento formal para auxiliar os decisores na hierarquização de forma objetiva dos alimentadores de energia elétrica mais críticos, proporcionando maior clareza e aprendizado em todo o processo de planejamento da expansão do sistema elétrico. Ao final, desenvolveu-se uma ferramenta para tratamento do grande volume de dados, que disponibiliza as informações depuradas para auxiliar na tomada decisão de investimento em ações eficientes, que melhorem a qualidade do fornecimento e atendam o crescimento do sistema. A partir da revisão bibliográfica e com a aplicação do método, oportunidades para estudos futuros foram identificadas. / The expansion planning of the electric system is one of the main activities in an electric energy distributor, representing a large part of the investments made by the distributors to meet the consumer demand and the criteria established by the regulatory agency (ANEEL). The companies seek the support of multi-criteria methods in the investment decision-making process, to optimize and prioritize, in order to succeed in the elaboration of a work plan which contemplates technical and economic aspects. The systemic review of the literature was carried out in current and relevant articles for the subject under study, with the aid of five database sources. The theoretical reference, which totals 52 publications, presents theoretical concepts on the decision process through multicriteria methods of decision support, as well as exemplifies through practical applications how the methods are have been used in the area of energy. Based on this review, it was possible to structure the application of the Multiattribute Utility Theory (MAUT) in an investment decision process for the purpose of planning the expansion of the distribution system in an electric power distribution concessionaire. The application of the method shows the importance of a formal procedure to assist decision makers in the objective hierarchy of the most critical electric power feeders, providing greater clarity and learning throughout the planning process of the expansion of the electric system. In the end, a tool was developed to treat the large volume of data, which provides the purified information to assist in the decision making of investment in assertive actions that improve the quality of supply and meet growth of the system. From the literature review and with the application of the method, opportunities for future studies have been identified.
38

Tomada de decisão de investimento através de método multicritério para fins de planejamento da expansão da distribuição

Pressi, Roberto André January 2017 (has links)
O planejamento da expansão do sistema elétrico é uma das principais atividades em uma distribuidora de energia elétrica, representando uma grande parcela dos investimentos realizados pelas distribuidoras para atender a demanda dos consumidores e os critérios estabelecidos pela agência reguladora (ANEEL). As empresas buscam o apoio de métodos multicritério no processo decisório de investimento, para otimizar e priorizar, com o intuito de obterem êxito na elaboração de um plano de obras que contemple aspectos técnicos e econômicos. A revisão sistêmica da literatura foi realizada em trabalhos de relevância para o tema em estudo, com auxílio de cinco bases de dados. O referencial teórico, que totaliza 52 publicações, apresenta conceitos teóricos sobre o processo decisório através de métodos multicritério de apoio à decisão, bem como exemplifica, através de aplicações práticas como os métodos estão sendo utilizados na área de energia. Com base nesta revisão foi possível estruturar a aplicação da Teoria da Utilidade Multiatributo (MAUT) em um processo decisório de investimento para fins de planejamento da expansão do sistema de distribuição em uma concessionária distribuidora de energia elétrica. Com a aplicação do método fica evidenciada a importância de um procedimento formal para auxiliar os decisores na hierarquização de forma objetiva dos alimentadores de energia elétrica mais críticos, proporcionando maior clareza e aprendizado em todo o processo de planejamento da expansão do sistema elétrico. Ao final, desenvolveu-se uma ferramenta para tratamento do grande volume de dados, que disponibiliza as informações depuradas para auxiliar na tomada decisão de investimento em ações eficientes, que melhorem a qualidade do fornecimento e atendam o crescimento do sistema. A partir da revisão bibliográfica e com a aplicação do método, oportunidades para estudos futuros foram identificadas. / The expansion planning of the electric system is one of the main activities in an electric energy distributor, representing a large part of the investments made by the distributors to meet the consumer demand and the criteria established by the regulatory agency (ANEEL). The companies seek the support of multi-criteria methods in the investment decision-making process, to optimize and prioritize, in order to succeed in the elaboration of a work plan which contemplates technical and economic aspects. The systemic review of the literature was carried out in current and relevant articles for the subject under study, with the aid of five database sources. The theoretical reference, which totals 52 publications, presents theoretical concepts on the decision process through multicriteria methods of decision support, as well as exemplifies through practical applications how the methods are have been used in the area of energy. Based on this review, it was possible to structure the application of the Multiattribute Utility Theory (MAUT) in an investment decision process for the purpose of planning the expansion of the distribution system in an electric power distribution concessionaire. The application of the method shows the importance of a formal procedure to assist decision makers in the objective hierarchy of the most critical electric power feeders, providing greater clarity and learning throughout the planning process of the expansion of the electric system. In the end, a tool was developed to treat the large volume of data, which provides the purified information to assist in the decision making of investment in assertive actions that improve the quality of supply and meet growth of the system. From the literature review and with the application of the method, opportunities for future studies have been identified.
39

Caracterização e estudo do gerenciamento dos resíduos sólidos urbanos em um consórcio municipal do estado de pernambuco

MELO, Fernando Henrique Ferreira De Alves 15 December 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-09-19T19:33:20Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissetacao FERNANDO HENRIQUE CORREÇÕES-DEFESA - FINAL.pdf: 4579522 bytes, checksum: e73435d4ab5a91c6938070db7c3beef4 (MD5) / Made available in DSpace on 2016-09-19T19:33:20Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissetacao FERNANDO HENRIQUE CORREÇÕES-DEFESA - FINAL.pdf: 4579522 bytes, checksum: e73435d4ab5a91c6938070db7c3beef4 (MD5) Previous issue date: 2015-12-15 / CAPES / O aumento na geração de resíduos resultantes do modo de vida fundamentado no consumo em massa e a aceleração do crescimento populacional têm causado diversos impactos negativos, degradando os bens e serviços ambientais. No Brasil, os problemas originados pela má gestão municipal dos resíduos sólidos urbanos qualificam os RSU como um dos mais difíceis e complexos problemas enfrentados pela sociedade moderna. Aliada a isso, a escassez de recursos de infraestrutura e de recursos de ordem técnico-cientifica, tornam os resíduos sólidos urbanos um desafio de alta magnitude, sobretudo para os municípios de pequeno porte. Buscando alternativas para a promoção correta da gestão dos resíduos, que caminhem sinergicamente com o ordenamento jurídico, prevendo o tratamento e destinação por parte do gerador em locais ambientalmente adequados. As tecnologias de tratamento e disposição final de resíduos, fundamentadas em modelos de gestão, que adotem tecnologias contemporâneas, difundidas em países desenvolvidos são imprescindíveis no enfrentamento do problema. Ferramentas de apoio à decisão são fundamentais para auxiliar a escolha de métodos alternativos de tratamento e disposição final ambientalmente corretos, socialmente justos e economicamente viáveis. Essa realidade motivou a pesquisa que visa a utilização e estudo de uma ferramenta de apoio à decisão desenvolvida como resultado do projeto “Análise das diversas tecnologias de tratamento e disposição final de resíduos sólidos no Brasil, Europa, Estados Unidos e Japão” para propor as melhores rotas tecnológicas de tratamento e disposição final nos municípios de Altinho, Agrestina, Belém de Maria, Bonito e Lagoa dos Gatos, que fazem parte do COMAGSUL - Consórcio dos Municípios do Agreste e Mata Sul. Nesse intuito, utilizou-se a ferramenta IST Versão 1.0 de 2014 para possibilitar a hierarquização de rotas tecnológicas de tratamento e destino final dos resíduos, além da análise comparativa com a gestão adotada no Brasil e para o estado de Pernambuco. A utilização da ferramenta produziu como resultado final a indicação de três rotas tecnológicas com elevado índice de sustentabilidade ambiental IST. Esses resultados apontam a adequação da ferramenta para proposição de rotas tecnológicas de tratamento e disposição final em consonância com a Política Nacional de Resíduos, podendo sua utilização ser altamente viável quanto a tomada de decisão em consórcios públicos. / The increase in the generation of waste resulting from the reasoned way of life in mass consumption and the acceleration of population growth have caused several negative impacts, degrading environmental goods and services. In Brazil, the problems caused by poor municipal management of solid urban waste qualifies the MSW as one of the most difficult and complex problems faced by modern society. Allied to this, the scarcity of infrastructure resources and resources of technical-scientific, order make solid urban waste a challenge of high magnitude, especially for small towns. Seeking alternatives to the correct promotion of waste management that they may walk synergistically with the legal system, providing for the treatment and disposal by the generator in environmentally suitable locations. The technologies of treatment and final disposal of waste, founded in management models, that adopt contemporary technology, disseminated in developed countries are essential in tackling the problem. Decision support tools are fundamental to assist the choice of alternative methods of treatment and final disposal environmentally correct, socially fair and economically viable. This reality motivated research that seeks to use a decision support tool developed and study as a result of the project "Analysis of various technologies for treatment and final disposal of solid waste in Brazil, Europe, United States and Japan" to propose the best technological routes of treatment and final disposal in the municipalities of Altinho, Agrestina, Belem de Maria, Bonito and Lagoa dos Gatos, which are part of the COMAGSUL - Consortium of Municipalities of the Agreste and South Wood. For this reason, it used the IST Tool Version 1.0 2014 to enable the hierarchy of technological routes of treatment and final destination of the waste, in addition to the comparative analysis with the management adopted in Brazil and for the state of Pernambuco. The use of the tool has produced as a final result the indication of three technological routes with a high index of environmental sustainability IST. These results indicate the suitability of the tool to the proposition of technological routes of treatment and final disposal in line with the National Policy of waste, its use may be highly viable as decision making in public consortia.
40

An agent-based forest sector modeling approach to analyzing the economic effects of natural disturbances

Schwab, Olaf Sebastian 05 1900 (has links)
This dissertation describes the development of CAMBIUM, an agent-based forest sector model for large-scale strategic analysis. This model is designed as a decision support tool for assessing the effect that changes in forest product demand and resource inventories can have on the structure and economic viability of the forest sector. CAMBIUM complements existing forest sector models by modeling aggregate product supply as an emergent property of individual companies’ production decisions and stand-level ecological processes. Modeling the forest products sector as a group of interacting autonomous agents makes it possible to introduce production capacity dynamics and the potential for mill insolvencies as factors in modeling the effects of market and forest inventory based disturbances. This thesis contains four main manuscripts. In the first manuscript I develop and test a dispersal algorithm that projects aggregated forest inventory information onto a lattice grid. This method can be used to generate ecologically and statistically consistent datasets where high-quality spatial inventory data is otherwise unavailable. The second manuscript utilizes this dataset in developing a provincial-level resource dynamics model for assessing the timber supply effects of introducing weevil-resistant spruce. This model employs a stand-level approach to simulating weevil infestation and associated merchantable volume losses. Provincial-level impacts are determined by simulating harvest activities over a 350 year time horizon. In the third manuscript I shift the focus to interactions between forest companies. I analyze the effects of strategic decisions on sector structure by developing CAMBIUM as an agent-based model of competition and industry structure evolution. The forest sector is modeled as a group of autonomous, interacting agents that evolve and compete within the limitations posed by resource inventories and product demand. In the final manuscript I calibrate CAMBIUM to current conditions in the British Columbia forest sector. Industry agents compete for roundwood inputs, as well as for profits in finished product markets for pulp, panel products, and lumber. To test the relevance and utility of this model, CAMBIUM is used to quantify the cumulative impacts of a market downturn for forest products and mountain pine beetle induced timber supply fluctuations on the structure of the forest sector. / Forestry, Faculty of / Graduate

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