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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.
121

Developing a Hierarchical Decision Model to Evaluate Nuclear Power Plant Alternative Siting Technologies

Lingga, Marwan Mossa 24 May 2016 (has links)
A strong trend of returning to nuclear power is evident in different places in the world. Forty-five countries are planning to add nuclear power to their grids and more than 66 nuclear power plants are under construction. Nuclear power plants that generate electricity and steam need to improve safety to become more acceptable to governments and the public. One novel practical solution to increase nuclear power plants' safety factor is to build them away from urban areas, such as offshore or underground. To date, Land-Based siting is the dominant option for siting all commercial operational nuclear power plants. However, the literature reveals several options for building nuclear power plants in safer sitings than Land-Based sitings. The alternatives are several and each has advantages and disadvantages, and it is difficult to distinguish among them and choose the best for a specific project. In this research, we recall the old idea of using the alternatives of offshore and underground sitings for new nuclear power plants and propose a tool to help in choosing the best siting technology. This research involved the development of a decision model for evaluating several potential nuclear power plant siting technologies, both those that are currently available and future ones. The decision model was developed based on the Hierarchical Decision Modeling (HDM) methodology. The model considers five major dimensions, social, technical, economic, environmental, and political (STEEP), and their related criteria and sub-criteria. The model was designed and developed by the author, and its elements' validation and evaluation were done by a large number of experts in the field of nuclear energy. The decision model was applied in evaluating five potential siting technologies and ranked the Natural Island as the best in comparison to Land-Based, Floating Plant, Artificial Island, and Semi-Embedded plant.
122

Novos métodos para reconfiguração das redes de distribuição a partir de algoritmos de tomadas de decisão multicriteriais / New methods for distribution networks reconfiguration starting from multiple criteria decision-making algorithms

Bernardon, Daniel Pinheiro 14 December 2007 (has links)
The electric networks reconfiguration has as purpose: to reduce the energy losses, to improve the voltage profile for the customers, to increase the reliability levels or to re-establish the energy supply in contingency situations. In spite of the complexity of this combinatorial problem of large dimensions, there is an effort of the researchers in the direction of efficient optimization methods, once the classic methods present difficulties for its resolution. The disadvantage of these methods is that a major part of researchers ignores the totality of formal information that is available in the power utilities. The efficient solution should also consider the knowledge and experience of power utilities professionals that can be accomplished starting from the development of Specialist Systems. For these reason, it becomes more recommended to consider algorithms that make possible the use of formal and informal analysis methods. This context motivated this thesis whose proposal is the development of new methods and software for distribution networks reconfiguration starting from multiple criteria decision-making methods, aiming at a more adequate processing of all available information in power utilities. To solve the approached problem, this paper uses the Bellman-Zadeh s method that was shown efficient in the solution of several problems of multiple criteria decision, besides allowing the analysis, at the same time, of quantitative and qualitative criteria. In general, the reconfiguration can not be solved in an efficient way without the analysis of the following problems: the appropriate modeling of the equipments and electrical loads; the creation of algorithm for representation of the electrical topology that allows fast changes in the electric configuration; calculations of the load flow; the definition of composition and presentation forms for the target functions and restrictions; the development of optimization methods and software to define the best electric configuration in normal operation state and in contingency situations. The proposed methodologies were customized according to the power utilities needs, helping the operators in the decision-making process. Besides that the algorithms meet the demand for fast processing of the efficient solutions, which is fundamental mainly in the re-establishment of energy supply during contingencies. Among the several advantages of the developed software in relation to the conventional softwares, the most important are: the representation of the electric topology considers only the information of the connections that really exist, dispensing the use of matrixes; integration with the electric load modeling systems for maximum demand as for load typical curves; the use of the initial data reliability to coordinate the tranformers load; application of multiple criteria optimization algorithms for distribution networks reconfiguration, in normal operational state and in contingency situations; composition of the target functions and restrictions considering quantitative and qualitative characteristics; evaluation of the impact of the reconfiguration in the power systems energy losses. As results, case studies are presented with real data from the power utilities, in order to prove the efficiency of the proposed methods. / A reconfiguração das redes elétricas tem como finalidade: reduzir as perdas de energia, melhorar o perfil de tensão para os consumidores, aumentar os níveis de confiabilidade ou restabelecer o fornecimento de energia em situações de contingência. Apesar da complexidade desse problema combinatorial de grandes dimensões, há todo um esforço, por parte dos pesquisadores, no sentido de buscar métodos eficazes de otimização, uma vez que os métodos clássicos apresentam dificuldades para sua resolução. A desvantagem destes trabalhos é que a maioria deles praticamente ignora a totalidade da informação formal, que está disponível nas concessionárias. No entanto, para uma solução eficiente, também deve-se considerar o conhecimento e a experiência dos profissionais das concessionárias, que pode ser realizado a partir do desenvolvimento de Sistemas Especialistas. Por essas razões, torna-se mais indicado desenvolver algoritmos que possibilitem reunir métodos de análise formais e informais. Essas constatações motivaram a realização deste trabalho. Nele, propõese o desenvolvimento de novos métodos e de uma ferramenta computacional para reconfiguração das redes de distribuição a partir de métodos de tomada de decisão multicriteriais, visando ao processamento adequado das fontes de informação disponíveis nas concessionárias. Para resolver o problema abordado, este trabalho utiliza o método de Bellman-Zadeh, que se mostrou eficiente para a solução de questões envolvendo múltiplos critérios, permitindo não apenas a análise de critérios quantitativos, mas também qualitativos. Em geral, a questão de reconfiguração não pode ser solucionada de forma otimizada, sem a análise dos seguintes problemas: modelagem adequada dos elementos pertencentes às redes de distribuição e das cargas elétricas; criação de algoritmo para representação da topologia das redes, que permita realizar rápidas alterações na configuração; cálculos do fluxo de potência; definição da composição e formas de apresentação para as funções objetivo e restrições; desenvolvimento de métodos de otimização e software para definir a configuração elétrica ideal, em regime normal de operação e em situações de contingência. As metodologias propostas foram customizadas de acordo com as necessidades das concessionárias, ajudando os operadores no processo de tomada de decisão. Além disso, os algoritmos atendem à exigência de processamento rápido na definição da solução eficiente, que é fundamental principalmente quando se tratar de restauração de energia em situações de contingência. Dentre as vantagens desse sistema em relação aos softwares convencionais, destacam-se as seguintes: representação da topologia elétrica das redes de distribuição, considerando somente a informação das ligações que existem de fato, dispensando o uso de matrizes; integração com os sistemas de modelagem da carga elétrica tanto por demanda máxima quanto por curvas típicas de carga; uso da confiabilidade dos dados iniciais para coordenação da carga dos transformadores de distribuição; aplicação de algoritmos de otimização e de análise multicriteriais para reconfiguração das redes, em regime normal de operação e em situações de contingência; composição das funções objetivo e restrições, considerando características quantitativas e qualitativas; avaliação do impacto das reconfigurações nas perdas elétricas dos sistemas de potência. Como resultados, são apresentados estudos de casos com dados reais das concessionárias de energia elétrica, com o objetivo de comprovar a eficiência dos métodos propostos.
123

Integration of multi-criteria tools in geographical information systems / Intégration d'outils multicritères dans les systèmes d'information géographique

Lidouh, Karim 13 January 2014 (has links)
For a little over twenty years, researchers have worked on integrating multi-criteria aggregation procedures (MCAP) to GIS. Several notable contributions have brought this field to what it is today. After studying the course of MCDA-GIS integration through several works, we question the future of such an attempt. Indeed most works that aim for an integration do not survive long after their direct purpose has been fulfilled. We end up understanding through a critical review of the existing systems that technical integration means nothing if it is not visible to the user on an operational level.<p><p>We therefore propose several contributions to improve the usability of MCDA methods in a geographic context. One of our works consists in adapting the PROMETHEE-GAIA methodology to be used on maps for spatially referenced problems. To do so, we define symbols/glyphs that display select parts of the results obtained through the PROMETHEE and GAIA methods. This allows for the comparison of alternatives' profiles and characteristics based on their geographic location which wasn't possible before. This adaptation helps us combine multicriteria and geographic aspects in an entirely new way.<p>We also propose some extensions of the GAIA method to improve the quality of the results and reduce the risk of wrong interpretations to be made due to losses of data. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
124

Prudent ranking rules: theoretical contributions and applications

Lamboray, Claude 03 October 2007 (has links)
Arrow and Raynaud introduced a set of axioms that a ranking rule should verify. Among these, axiom V' states that the compromise ranking should be a so-called prudent order. Intuitively, a prudent order is a linear order such that the strongest opposition against this solution is minimal. Since the related literature lacks in solid theoretical foundations for this type of aggregation rule, it was our main objective in this thesis to thoroughly study and gain a better understanding of the family of prudent ranking rules. We provide characterizations of several prudent ranking rules in a conjoint axiomatic framework. We also prove that we can construct profiles for which the result of a prudent ranking rule and a non-prudent ranking rule can be contradictory. Finally we illustrate the use of prudent ranking rules in a group decision context and on the composite indicator problem.<p><p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
125

A Measurement System for Science and Engineering Research Center Performance Evaluation

Gibson, Elizabeth Carole 07 November 2016 (has links)
This research provides performance metrics for cooperative research centers that enhance translational research formed by the partnership of government, industry and academia. Centers are part of complex ecosystems that vary greatly in the type of science conducted, organizational structures and expected outcomes. The ability to realize their objectives depends on transparent measurement systems to assist in decision making in research translation. A generalizable, hierarchical decision model that uses both quantitative and qualitative metrics is developed based upon program goals. Mission-oriented metrics are used to compare the effectiveness of the cooperative research centers through case studies. The US National Science Foundation (NSF) industry university cooperative research center (IUCRC) program is the domain of organizational effectiveness because of its longevity, clear organizational structure, repeated use and availability of data. Not unlike a franchise business model, the program has been replicated numerous times gaining recognition as one of the most successful federally funded collaborative research center (CRC) programs. Understanding IUCRCs is important because they are a key US policy lever for enhancing translational research. While the program model is somewhat unique, the research project begins to close the gap for comparing CRCs by introducing a generalizable model and method into the literature stream. Through a literature review, program objectives, goals, and outputs are linked together to construct a four-level hierarchical decision model (HDM). A structured model development process shows how experts validate the content and construct of the model using these linked concepts. A subjective data collection approach is discussed showing how collection, analysis and quantification of expert pair-wise-comparison data is used to establish weights for each of the decision criteria. Several methods are discussed showing how inconsistency and disagreement are measured and analyzed until acceptable levels are reached. Six case studies are used to compare results, evaluate the impact of expert disagreement and conduct criterion-related validity. Comparative analysis demonstrates the ability of the model to efficiently ascertain criteria that are relatively more important towards each center's performance score. Applying this information, specific performance improvement recommendations for each center are presented. Upon review, experts generally agreed with the results. Criterion-related validity discusses how the performance measurement scoring system can be used for comparative analysis among science and engineering focused research centers. Dendrograms highlight where experts disagree and provide a method for further disagreement analysis. Judgment quantification values for different expert clusters are substituted into the model one-at-a-time (OAT) providing a method to analyze how changes in decisions based on these disagreements impact the results of the model's output. This research project contributes to the field by introducing a generalizable model and measurement system that compares performance of NSF supported science and engineering focused research centers.
126

Hodnocení podílových fondů z hlediska vícekriteriálního rozhodování / Unit Trust Evaluation in Light of Multiple-Criteria Decision Making

Kaňoková, Jana January 2007 (has links)
The target of this work is to evaluate the unit trusts in light of the multiple-criteria decision making. The unit trusts are divided into the groups according to the investor categories: unit trusts with conservative, balanced and aggressive portfolio. The unit trusts were lined up by the medium of the multiple-criteria decision making methods (PRIAM, ORESTE, MAPPAC) and it is also made an analysis why have each of the methods chosen the particular unit trust in the group as the best compromise variant.
127

Postavení České spořitelny na bankovním trhu ČR / Position of Czech savings bank on the czech banking market

Gavlasová, Zuzana January 2009 (has links)
The main goal of this thesis is to analyse the position of the Ceska sporitelna bank (Czech savings bank) on the czech banking market by applicaion of multiple criteria decision making methods. Analysis is concetrate in two parts - the bank in its complexity and also in the product portfolio mainly in the area of current account as a most strategic banking product. The comparsion of banking products or banks at all is not a goal of this thesis. The thesis is concerned on a basic analysis based on certain presumpions and restrictions.
128

Studie importní logistiky ve výrobním podniku / The Study of Inbound Logistics in Manufactoring Company

Voráčová, Eliška January 2011 (has links)
The master's thesis is focused on optimal selection of transportation solution provider as a key activity of inbound logistics department of manufacturing company ABC s.r.o. The summary of general activities and objectives of inbound logistics are followed by the analysis of last selection procedure. Then there is mentioned suggestion of new selection procedure using the methods of Multiple Criteria Decision Making which is based on the knowledge from specialized logistical literature. This work assume that using the methods of Multiple Criteria Decision Making will result in more effective selection procedure in company ABC s.r.o.
129

Assessment of Solar Photovoltaic Technologies Using Multiple Perspectives and Hierarchical Decision Modeling

Sheikh, Nasir Jamil 14 April 2013 (has links)
The objective of this research is to build a decision model for a comprehensive assessment of solar photovoltaic technologies using multiple perspectives. These perspectives include: social, technological, economic, environmental, and political (STEEP) with each perspective consisting of multiple criteria. Hierarchical decision modeling and expert judgment quantification are used to provide the relative ranking of the perspectives and criteria. Such modeling is effective in addressing technology evaluations with competing and contrasting perspectives and criteria where both quantitative and qualitative measurements are represented. The model is then operationalized by constructing desirability functions for each criterion. The combined results provide an overall numerical score for each technology under consideration as well as criteria desirability gaps. This model is useful for assessing photovoltaic technologies from varying worldviews such as the electric utility worldview, the photovoltaic manufacturer's worldview, or the national policy worldview. This model can also provide guidance to decision makers and practitioners on areas of improvement for a selected technology. The research utilizes the electric utility worldview as a case study.
130

An integrated approach to environmentally conscious design and manufacturing

Goan, Meng-Jong Kuan 03 October 2007 (has links)
The problem addressed in this research was to develop an approach for the simultaneous green design of products and associated manufacturing processes including demanufacturing concerns. We propose a generic approach called Integrated Environmentally Conscious Design and Manufacturing (IECDM) which can be applied to address problems in the ECDM domain. IECDM incorporates environmental considerations into the engineering design process, thereby increasing a product's total life-cycle value (including its end-of-life value) as experienced by the customer, manufacturer, and society, while simultaneously reducing impacts on the environment caused by that product and its manufacturing processes. IECDM is a novel integration of Quality Function Deployment (QFD), Life-Cycle Assessment (LCA), Multiple Criteria Decision-Making (MCDM), and Cost-Benefit Assessment (CBA). The focus is on process, based on modification of the traditional QFD methodology to incorporate environmental issues and green product-design decisions through the life cycle design activities of synthesis, analysis, and evaluation. This dissertation presents a QFD-based IECDM approach, a mathematical CBA model, and an IDDS (Integrated Design Decision-Support) framework with a design-flow-chart application for incorporating environmental criteria into product and process eco-design. The IECDM problem is defined as: given the customer and environmental requirements, develop an integrated approach for green product design that results in maximization of the product's total life-cycle value (TLCV). Initially. through investigation in the field of ECDM, we specified a clear ECDM domain within Industrial Ecology. Then. we proposed various state-of-the-art techniques that were used to implement ECDM in the literature. After we defined the IECDM problem. we developed an integrated approach that led to a generic QFD-IECDM methodology for dealing with problems in the ECDM domain. Finally, for implementing the proposed methodology, we developed a tentative IODS framework to encourage long-term development followed by an example. / Ph. D.

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