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A model for Assessing Cost Effectiveness of Applying Lean Tools - A case studyAlhamed, Heba, Qiu, Xiaojin January 2007 (has links)
<p>The purpose of this thesis is to develop a model for assessing cost effectiveness of applying lean tools. The model consists of eight phases: it starts by understanding customers' requirements using Voice of Customer (VOC) and Quality Function Deployment (QFD) tools. In phase 2, the current state of plant is assessed using lean profile charts based on Balanced Scorecard (BSC) measures. In phase 3 and phase 4, identification of critical problem(s) and generating of improvement suggestion(s) are performed. Phase 5 provide evaluation of the cost effectiveness of implementing the suggested lean methods based on life cycle cost analysis (LCCA) and phase 6 prefers the right alternative based on multiple criteria decision making (MCDM). In phase 7 the selected alternative is supposed to be implemented and finally the user should monitor and control the process to make sure that the improvement is going as planned. The model was verified successfully using a case study methodology at one Swedish sawmill called Södra Timber in Ramkvilla, one part of Södra group. Results obtained from the study showed that the production and human resources perspectives are the most critical problem areas that need to be improved. They got the lowest scores in the lean profile, 63% and 68%, respectively. Using value stream mapping (VSM) it was found that the non value added (NVA) ratios for the core and side products are 87.4% and 90.4%, respectively. Using the model, three improvement alternatives were suggested and evaluated using LCCA and MCDM. Consequently, implementing 5S got the highest score, second came redesigning the facility layout. However, it was estimated that 4.7 % of NVA for the side product would be reduced by redesigning the facility layout. The recommendations were suggested for the company to improve their performance. The novelty of the thesis is based on the fact that it addresses two main issues related to lean manufacturing: firstly, suggesting lean techniques based on assessment of lean profile that is based on BSC and QFD, and secondly assessing the cost effectiveness of the suggested lean methods based on LCCA and MCDM. This thesis provides a generalized model that enables the decision-maker to know and measure, holistically, the company performance with respect to customer requirements. This will enable the company to analyze the critical problems, suggest solutions, evaluate them and make a cost effective decision. Thus, the company can improve its competitiveness.</p>
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An efficient approach for high-fidelity modeling incorporating contour-based sampling and uncertaintyCrowley, Daniel R. 13 January 2014 (has links)
During the design process for an aerospace vehicle, decision-makers must have an accurate understanding of how each choice will affect the vehicle and its performance. This understanding is based on experiments and, increasingly often, computer models. In general, as a computer model captures a greater number of phenomena, its results become more accurate for a broader range of problems. This improved accuracy typically comes at the cost of significantly increased computational expense per analysis.
Although rapid analysis tools have been developed that are sufficient for many design efforts, those tools may not be accurate enough for revolutionary concepts subject to grueling flight conditions such as transonic or supersonic flight and extreme angles of attack. At such conditions, the simplifying assumptions of the rapid tools no longer hold. Accurate analysis of such concepts would require models that do not make those simplifying assumptions, with the corresponding increases in computational effort per analysis. As computational costs rise, exploration of the design space can become exceedingly expensive. If this expense cannot be reduced, decision-makers would be forced to choose between a thorough exploration of the design space using inaccurate models, or the analysis of a sparse set of options using accurate models. This problem is exacerbated as the number of free parameters increases, limiting the number of trades that can be investigated in a given time. In the face of limited resources, it can become critically important that only the most useful experiments be performed, which raises multiple questions: how can the most useful experiments be identified, and how can experimental results be used in the most effective manner?
This research effort focuses on identifying and applying techniques which could address these questions. The demonstration problem for this effort was the modeling of a reusable booster vehicle, which would be subject to a wide range of flight conditions while returning to its launch site after staging. Contour-based sampling, an adaptive sampling technique, seeks cases that will improve the prediction accuracy of surrogate models for particular ranges of the responses of interest. In the case of the reusable booster, contour-based sampling was used to emphasize configurations with small pitching moments; the broad design space included many configurations which produced uncontrollable aerodynamic moments for at least one flight condition. By emphasizing designs that were likely to trim over the entire trajectory, contour-based sampling improves the predictive accuracy of surrogate models for such designs while minimizing the number of analyses required.
The simplified models mentioned above, although less accurate for extreme flight conditions, can still be useful for analyzing performance at more common flight conditions. The simplified models may also offer insight into trends in the response behavior. Data from these simplified models can be combined with more accurate results to produce useful surrogate models with better accuracy than the simplified models but at less cost than if only expensive analyses were used. Of the data fusion techniques evaluated, Ghoreyshi cokriging was found to be the most effective for the problem at hand.
Lastly, uncertainty present in the data was found to negatively affect predictive accuracy of surrogate models. Most surrogate modeling techniques neglect uncertainty in the data and treat all cases as deterministic. This is plausible, especially for data produced by computer analyses which are assumed to be perfectly repeatable and thus truly deterministic. However, a number of sources of uncertainty, such as solver iteration or surrogate model prediction accuracy, can introduce noise to the data. If these sources of uncertainty could be captured and incorporated when surrogate models are trained, the resulting surrogate models would be less susceptible to that noise and correspondingly have better predictive accuracy. This was accomplished in the present effort by capturing the uncertainty information via nuggets added to the Kriging model.
By combining these techniques, surrogate models could be created which exhibited better predictive accuracy while selecting the most informative experiments possible. This significantly reduced the computational effort expended compared to a more standard approach using space-filling samples and data from a single source. The relative contributions of each technique were identified, and observations were made pertaining to the most effective way to apply the separate and combined methods.
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Multi-criteria decision making and geographical information systems : an extension for ArcViewBester, Frederick Johannes 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Multi-criteria decision-making (MCDM) is a set of techniques designed specifically for the analysis
of complex problems. Geographical Information Systems (GIS) focus on spatial problem-solving
and spatial analysis. The integration of these methodologies offers a powerful approach to decision
making. Despite the fact that most spatial decision problems are multi-criteria problems by nature,
the process of MCDM is not well established or effectively integrated into the field of spatial
analysis and GIS.
This research focuses on bridging the gap between MCDM and GIS. To this end, a generic MCDM
extension was designed and implemented in ArcView. As a result, a first version MCDM extension
is offered. The extension expands ArcView's functionality with a limited set of MCDM methods.
This functionality is illustrated on two problems involved with developing the tourism potential at
Coutada 16 Wildlife Reserve in Mozambique.
The MCDM extension facilitates procedures that allow the evaluation of spatial problems and
includes the ability to deal with both raster and vector data. This system offers a generic problemsolving
environment, which can be used to evaluate geographical problems of any nature. This
research identifies a number of improvements to the developed functionality and successfully
illustrates the potential problem-solving capabilities associated with MCDM integrated with
ArcView. / AFRIKAANSE OPSOMMING: Multi Kriteria Besluitneming (MKBN) is n versameling metodes vir die analise van komplekse
probleme. Geografiese Inligtingstelsels (GIS) fokus op geografiese probleemoplossing en analise.
Die integrasie van hierdie twee metodologieë bied 'n kragtige benadering tot besluitneming. Ten
spyte daarvan dat die meeste geografiese probleme in wese meerveranderlik van aard is, is MKBN
nie effektiefbinne die raamwerk van GIS geïntegreer nie.
Hierdie studie fokus op die oorbrugging van die gaping tussen MKBN en GIS. Met hierdie doel
voor oë is 'n generiese MKBN-uitbreiding vir ArcView ontwerp en geïmplementeer. Die resultaat
is 'n eerste- weergawe MKBN-uitbreiding. Die uitbreiding brei ArcView se funksionaliteit uit om
'n beperkte versameling MKBN-metodes in te sluit. Die nuut ontwikkelde funksies word
geïllustreer aan die hand van twee probleme wat die ontwikkeling van die toerismepotensiaal vir die
Coutada 16 Wildreservaat in Mosambiek aanspreek.
Die uitbreiding maak voorsiening vir 'n MKBN-evaluasie van geografiese probleme en besit die
vermoë om beide vektor- en roosterdata te analiseer. Hierdie stelsel verskaf 'n generiese omgewing
vir probleemoplossing wat gebruik kan word om byna enige geografiese probleem te analiseer. Die
studie identifiseer verbeteringe op en uitbreidings van die ontwikkelde funksies en slaag daarin om
die potensiaal van probleemoplossing wat deur die integrasie van MKBN-tegnieke met ArcView
moontlik gemaak word, te illustreer.
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Modelo para avaliação de desempenho em sustentabilidade nas operações de gestão municipal de resíduos / Model for sutainability performance assessment in the municipal waste management operationsRodrigues, Alexsandro Pinto 15 December 2017 (has links)
O desenvolvimento sustentável e a sustentabilidade estão sendo abordados como um novo paradigma econômico que estabelece um contexto geral para que organizações e instituições desenvolvam suas estratégias e processos, associados aos debates da responsabilidade socioambiental corporativa, particularmente para a administração pública, onde está ocorrendo um processo de mudança para o desenvolvimento de cidades sustentáveis e inteligentes. As operações complexas e fechadas definem estruturas para gerenciar o fluxo de materiais, energia e informações. Este documento aborda o problema da gestão de resíduos sólidos em pequenas cidades e, com base em uma revisão bibliográfica e um estudo de múltiplos casos em profundidade, propõe um sistema de medição como instrumentos de avaliação de desempenho ambiental que têm por função refletir as estratégias de gestão integrando as ações de sustentabilidade. Para analisar as práticas de desenvolvimento do modelo utilizar-se-á de uma adaptação da metodologia Multicritério de Apoio a Decisão Construtivista - MCDA-C, juntamente com aplicação da técnica de Painel de Especialistas, a qual possibilitará a comparação e confirmação dos objetivos propostos. Nos estudos de casos, com os indicadores obtidos do contexto, literatura e de especialistas da área, é desenvolvido o modelo, possibilitando a determinação do desempenho global da gestão de resíduos e os pesos das áreas de preocupações, a fim de refinar propor o modelo em outras administrações voltadas a gestão de resíduos. Por fim, o modelo para avaliação de desempenho da gestão municipal de resíduos se mostrou como uma importante ferramenta para melhorar o planejamento estratégico quando no controle e gerenciamento das dimensões sustentáveis da organização, identificando critérios que aprimoram e diagnosticando ações de melhorias, contribuindo na qualidade e custos dos serviços propostos na gestão. / The sustainability and sustainable development is being approached as a new economic paradigm that establishes a general context for organizations and institutions to develop their strategies and processes, associated to the debates of corporate social and environmental responsibility, particularly for public administration, where a process of change for the development of sustainable and smart cities. Complex and closed operations define structures to manage the flow of materials, energy, and information. This study addresses the problem of solid waste management in small cities and, based on a bibliographical review and a study of multiple in-depth cases, proposes a measurement system as instruments for the evaluation of environmental performance, whose function is to reflect the strategies of integrating sustainability actions. In order to analyze the development practices of the model, it will be used an adaptation of the Multicriteria Decision Aid – Constructivist - MCDA-C, together with the application of the Expert Panel technique, which will allow the comparison and confirmation of the proposed objectives. In the case studies, with the indicators obtained from the context, literature and specialists of the area, the model is developed, allowing the determination of the overall performance of waste management and the weights of the areas of concern, in order to refine the model proposed in other administrations focused on waste management. Finally, the model for evaluation of municipal waste management was shown as an important measure to improve strategic planning when it is not a control and management of sustainable dimensions of the organization, identifying criteria and solutions for improvement actions, contributing in the quality and costs of the proposed services in the management.
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Uso da análise multicritério para a seleção de tecnologias de tratamento de efluentes / Use of multicriteria analysis to select the wastewater treatment technologiesGoffi, Andreia dos Santos 01 June 2017 (has links)
Fundação Araucária; CNPq / O elevado número de alternativas somado ao número de variáveis, que nem sempre são mensuráveis e muitas vezes são conflitantes, torna a escolha do sistema de tratamento de efluentes um difícil processo de decisão. A fim de assegurar que a melhor alternativa seja selecionada é necessário uma análise aprofundada, que considere o maior número de aspectos relacionados à tomada de decisão. Deste modo, este trabalho forneceu uma nova abordagem para a seleção de tecnologias de tratamento de águas residuais, considerando as dimensões econômicas, sociais, técnicas e ambientais. O modelo seguiu três etapas, sendo a primeira a definição das alternativas do modelo, as quais foram definidas através do estudo da viabilidade econômica de 37 tecnologias usuais no cenário brasileiro. Na segunda etapa, foram definidos dois grupos de critérios, de acordo com a vazão e a população, por meio da utilização do método de Copeland. E na terceira foi aplicado o método PROMETHEE II para ranqueamento das alternativas. Considerando os aspectos avaliados, as tecnologias infiltração lenta, infiltração rápida e lagoa anaeróbia seguida de lagoa facultativa foram as alternativas preferidas para as pequenas comunidades, ao passo que os sistemas UASB, seguido de póstratamento foram as opções menos preferidas. Para os centros urbanos as alternativas de destaque foram: infiltração rápida, reator UASB com filtro anaeróbio, já as de menor potencial foram os sistemas de lagoas. Os resultados contribuem para o desenvolvimento do saneamento, uma vez que o trabalho forneceu um processo de determinação mais robusto para seleção de tecnologias de tratamento, avaliando os critérios relevantes, como diretrizes para a determinação. / The high number of alternatives added to the number of variables, which are not always measurable and often conflicting, makes choosing the wastewater treatment system a difficult decision process. In order to ensure that the best alternative is selected, a depth analysis is required, which considers the greatest number of decision-making aspects. Therefore, this work has provided a new approach for the selection of wastewater treatment technologies, considering the economic, social, technical and environmental dimensions. The model has followed three stages: the first one was the definition of the model alternatives, which were defined through the economic viability study of 37 technologies usual in Brazil; in the second
stage, two groups of criteria were defined, according to flow rate and population, using the Copeland method; and in the third one, the PROMETHEE II method was applied in order to rank the alternatives. Considering the aspects evaluated, the technologies as slow and fast infiltration, anaerobic pond followed by facultative pond were the preferred alternatives for small communities, while UASB systems followed by post-treatment were the less preferred options. For the urban groups the preferred alternatives were: fast infiltration, UASB reactor with anaerobic filter, while the ones with the least potential were the pond systems. The results contribute to the sanitation development, since the work has provided a robust determination process for the selection of the treatment technologies, by evaluating the most relevant criteria.
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Metodologia de manutenção preditiva para motores elétricos baseada em monitoramento de variáveis físicas e análise multicritério / Predictive maintenance methodology for electric motors, based on monitoring of physical variables and multicriteria analysisLeme, Murilo Oliveira 19 December 2017 (has links)
Este trabalho apresenta o desenvolvimento de uma metodologia de manutenção preditiva para motores elétricos, que utiliza a técnica de monitoramento de variáveis, transmissão de dados pela rede elétrica (Powerline Communication) e um tratamento com os métodos multicritério para classificação (ELECTRE TRI e AHPSort) e ordenação (ELECTRE II) dos motores que apresentam condição de falha incipiente, além do aproveitamento das instalações elétricas existentes para a aquisição de dados do funcionamento de motores elétricos tais como: tensão, corrente, temperatura e vibração. Essas informações podem ser avaliadas e tratadas através de métodos multicritério para alocar os motores em classes que representam estados de funcionamento normal, aceitável e falha incipiente. Assim, nos motores classificados em condição de falha incipiente pode ser realizado um ranking para apontar o motor em pior estado de funcionamento. Neste trabalho, foi conduzido um ensaio de falhas programadas em bancada com um período de aquisição de 1 minuto das variáveis de funcionamento de seis motores. Neste período, pode ser feito o registro do motor que apresentou as condições mais críticas para a falha, considerando as variáveis medidas como critérios na análise. Após um largo período de análise, foram computadas todas as vezes que cada motor foi classificado na classe de falha incipiente e ranqueado em primeiro lugar, significando que ele possui condições fora do padrão normal de funcionamento e piores que dos outros motores analisados. Com isso, foi possível identificar o motor que, por mais vezes, esteve em condição de falha incipiente, refletindo as falhas inseridas durante o ensaio. Essa metodologia possibilitou indicar ao gestor da manutenção, os desvios do funcionamento normal de motores elétricos, considerando mais de uma variável ao mesmo tempo, alinhado aos objetivos do decisor, através dos pesos calculados para os critérios, limites e preferências estabelecidas em cada método multicritério utilizado na metodologia proposta neste trabalho. / This work presents the development of a predictive maintenance methodology for electric motors, which uses the variable monitoring technique, data transmission through the electric network (Powerline Communication) and a treatment with multicriteria methods for sorting (ELECTRE TRI and AHPSort) and ranking (ELECTRE II) electric motors with incipient failure condition and the use of existing electrical installations for the acquisition of data of the operation of electric motors such as voltage, current, temperature and vibration. This information can be evaluated and treated through multicriteria methods to allocate motors in classes that represent normal, acceptable, and incipient failure states. Thus, in electric motors classified as incipient failure condition, a ranking can be performed to detect the engine in the worst operating state. In this work, a bench experiment was conducted with a 1-minute acquisition period of the operating variables in 6 motors. In this period, the electric motor can be registered that presented the most critical conditions for the fault, considering the measured variables as criteria in the analysis. After a longer period of analysis, we computed every time this engine was classified in the incipiente failure and first rank class, which means that it has conditions that are out of the normal operating range and worse than the other engines analyzed. Through this methodology it is possible to indicate to the maintenance manager deviations from the normal operation of electric motors, considering more than one variable at the same time aligned to the objectives of the decision maker, through the weights calculated for the criteria and limits and preferences established in each multicriteria method used in the methodology proposed in this work.
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Reconfiguração de redes de distribuição de energia considerando variáveis multiatributo no desenvolvimento de novas topologias / Reconfiguration of power distribution networks considering multi-attribute variables in the development of new topologiesTimossi, Marcelo Santiago 26 August 2016 (has links)
As redes inteligentes ou smart grids surgiram como um dos principais agentes dentro da reestruturação que o sistema elétrico de potência vem sofrendo há alguns anos. Mais especificamente, essa evolução vem tomando destaque nas redes de distribuição de energia elétrica. O surgimento de novos equipamentos, com tecnologia moderna, permite que o sistema seja monitorado em tempo real e manobrado de forma remota mediante as necessidades. Com o objetivo de otimizar cada vez mais as funcionalidades desses equipamentos, aplicando e promovendo sistemas capazes de funcionar de forma autônoma é que estudos vem desenvolvendo novas metodologias para atender as necessidades de recomposição das redes de distribuição diante à alguma anomalia. Um novo conceito que surgiu como vertente das redes inteligentes vem movendo o setor acadêmico e as concessionárias responsáveis pela distribuição de energia chamado reconfiguração de redes de distribuição, vem sendo tema de discussões e estudos sobre as melhores alternativas de implantação. Essa dissertação apresenta um modelo para utilização em sistemas baseado em reconfiguração, que identifique os melhores resultados para o conjunto quando é necessário fazer a transferência de carga de uma subestação de energia por perda em suas fontes de alimentação. O modelo leva em conta os principais índices de qualidade e continuidade de energia obtidos a partir de um método de busca exaustiva selecionando as melhores opções de manobras para reconfigurar os alimentadores mediante a uma anomalia no sistema de distribuição. O método multicritério PROMETHEE é utilizado para definir as melhores sequências de manobra na rede e consequentemente os melhores desempenhos para o sistema após o remanejamento das cargas. O modelo apresenta uma característica um pouco diferente dos que se encontra na literatura, pois não utiliza nenhum método de compensação para melhorar os índices de níveis de tensão e perdas de energia. A metodologia proposta foi avaliada e validade mediante a simulações em uma rede real pertencente a uma concessionária de energia elétrica e seus resultados apresentaram uma melhora significativa para o sistema de distribuição. / Smart grids have emerged as one of the key players in restructuring the electric power system has been suffering for some years. More specifically, this evolution has taken prominence in the electricity distribution networks. The emergence of new equipment with modern technology allows the system to be monitored in real time and operated remotely by the needs. In order to optimize more and more features of the equipment, applying and promoting systems that function autonomously is that research is developing new methodologies to meet the needs of restoration of distribution networks on the abnormality. A new concept that has emerged as component of smart grids has been moving the academic sector and the utilities responsible for distribution of energy called reconfiguration of distribution networks, has discussions and studies theme being on the best deployment of alternatives. This thesis presents a model for use in reconfiguring based systems, identifying the best results for the set when you need to load transfer of a loss of power substation in their power supplies. The model takes into account the main quality indicators and energy continuity obtained from an exhaustive search method selecting the best options maneuvers to reconfigure feeders by an anomaly in the distribution system. The multicriteria method PROMETHEE is used to define the best maneuver sequences on the network and therefore the best performance for the system after the relocation of cargo. The model presents a characteristic slightly different from that found in the literature, it does not use any compensation method for improving the rates of voltage levels and energy losses. The proposed methodology was evaluated and validity by simulations in a real network belonging to an electric utility and the results showed a significant improvement to the distribution system.
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Transgenética computacional aplicada a problemas de otimização combinatória com múltiplos objetivosAlmeida, Carolina Paula de 29 February 2012 (has links)
CNPq / A Transgenética Computacional é uma metáfora para o desenvolvimento de algoritmos evolucionários com base na teoria de evolução endossimbiótica e em outras interações do fluxo intracelular. Diversos algoritmos foram desenvolvidos com base nesta metáfora para problemas de Otimização Combinatória, em sua maioria com um único objetivo, obtendo bons resultados. Uma vez que a consideração de mais de um objetivo leva, em geral, a representações mais realistas de problemas práticos complexos, neste trabalho investiga-se o desenvolvimento de Algoritmos Transgenéticos para problemas multiobjetivo. Tais algoritmos são examinados em versões que utilizam elementos de outros algoritmos evolucionários multiobjetivo sendo eles o NSGA-II (Non-Dominated Sorting Genetic Algorithm-II) e o MOEA/D (Multi-objective Evolutionary Algorithm based on Decomposition). Diante disso, este trabalho propõe duas novas metodologias utilizando a Transgenética Computacional acoplada ao NSGA-II e ao MOEA/D, denominadas NSTA (Non-Dominated Sorting Transgenetic Algorithm) e MOTA/D (Multi-objective Transgenetic Algorithm based on Decomposition), respectivamente. Para avaliar o desempenho das técnicas propostas, os algoritmos desenvolvidos foram aplicados a dois problemas de Otimização Combinatória, NP-difíceis,em versões com mais de um objetivo. O primeiro problema é o Caixeiro Comprador Biobjetivo e o segundo o Quadrático de Alocação multiobjetivo. Foram realizados experimentos com casos de teste disponíveis em bancos utilizados comumente por outros trabalhos da literatura. Os resultados dos algoritmos propostos foram comparados com os resultados obtidos com os algoritmos evolucionários multiobjetivo que os inspiraram. A análise dos dados obtidos com os experimentos computacionais mostram que a versão MOTA/D é a mais eficiente dentre os algoritmos do experimento com relação a qualidade da aproximação da fronteira de Pareto. / The Computational Transgenetic is a metaphor for the development of evolutionary algorithms based on the theory of evolution endosymbiotic and other intracellular interactions flow. Several algorithms have been developed based on this metaphor for combinatorial optimization problems, mostly with a single objective, obtaining good results. Once the account of more than one objective provides, in general, more realistic representations of complex practical problems, this work investigates the development of Transgenetic Algorithms for multiobjective problems. Such algorithms are examined in versions that use elements of other multiobjective evolutionary algorithms such as the NSGA-II (Non-Dominated Sorting Genetic Algorithm-II) and the MOEA/D (Multi-objective Evolutionary Algorithm based on Decomposition). Therefore, this work proposes two new methods using Computational Transgenetic attached to NSGA-II and MOEA/D, named NSTA (Non-Dominated Sorting Transgenetic Algorithm) and MOTA/D (Multi-objective Transgenetic Algorithm based on Decomposition), respectively. To evaluate the proposed techniques performance, the experiments consider two NP-hard combinatorial optimization problems, in versions with more than one objective. The first problem is the Traveling Purchaser Problem and the second the Quadratic Assignment Problem. Experiments were performed with test cases available in benchmarks commonly used by other studies in the literature. The proposed algorithms' results were compared with those obtained by the multiobjetive evolutionary algorithms that inspired them. The analysis of data obtained by the computational experiment shows that the version MOTA/D is among the most efficient algorithms of the experiment with respect to the quality of the Pareto front approximation.
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Métodos TOPSIS y VIKOR en la verificación de la teoría de la ventaja de recursos en empresas textiles en Brasil / Métodos TOPSIS e VIKOR na verificação da resource advantage theory em empresas têxteis brasileiras / Methods TOPSIS and VIKOR at verification of resource advantage theory in brazilian textile companiesKreuzberg, Fernanda 10 April 2018 (has links)
This research had the objective to analyze the performance in Resources, Market and Financial explaining the competitive advantage of companies according to the Resource Advantage Theory, of Textile companies sector listed at BM&FBovespa. It analyzed 21 companies in the textile sector divided into four segments. For measuring performance have been adopted the Multiple Criteria Decision Making based on ideal scenarios, TOPSIS and VIKOR. It was analyzed the performances based on four indicators for resources, three for market and four for the financial dimension. The results point to the non-verification of RA Theory in textile companies, considering what it recommends that a business advantage in resources and market tends to be higher in the financial dimension. In this way, the only company that observed this factor was the Arezzo. Likewise for verification of such a theory would be consistent that there was correlation between the rankings of different dimensions, which was not the case. It was concluded that competitive advantage in resources and in market of companies, Brazil’s textile sector does not contribute to high performance in financial dimension. / Esta investigación tuvo como objetivo analizar los recursos de rendimiento, de mercado y financiera explicar la ventaja competitiva del negocio de acuerdo con la teoría de las ventajas de recursos (RA Teoría) de las empresas textiles enumerados en la BM&FBovespa. Ellos analizaron un total de 21 empresas del sector textil se divide en cuatro segmentos. Para la medición de los métodos de rendimiento fueron adoptadas para apoyar la toma multicriterio basado en ideal yescenarios, Topsis y Vikor. Se analizaron las actuaciones sobre la base de cuatro indicadores de recursos, tres para el mercado y cuatro para la dimensión financiera. Los resultados de la encuesta apuntan a la no verificación de la RA Teoría en las empresas textiles, teniendo en cuenta lo que se recomienda que una ventaja de negocio en recursos y el mercado tiende a ser mayor en la dimensión financiera. Por lo tanto la única compañía encontró que este factor fue el Arezzo. Del mismo modo para la verificación de tal teoría sería coherente que no había correlación entre la clasificación de diferentes dimensiones, que no era el caso. Por lo tanto, se concluye que la ventaja competitiva de los recursos y de Brasil, las empresas del sector textil de mercado no contribuye al desempeño financiero superior de las empresas. / Esta pesquisa teve por objetivo analisar o desempenho em recursos, mercado e financeiro que explicam a vantagem competitiva empresarial de acordo com a Resource Advantage Theory (RA Theory), de empresas do setor têxtil listadas na BM&FBovespa. Foram analisadas um total de 21 empresas do setor têxtil divididas em quatro segmentos. Para a mensuração do desempenho foram adotados os métodos de apoio a decisão multicritério baseados em cenários ideais TOPSIS e VIKOR. Foram analisados os desempenhos com base em quatro indicadores para recursos, três para mercado e quatro para a dimensão financeira. Os resultados da pesquisa apontam para a não verificação da RA Theory em empresas têxteis, considerando o que se preconiza de que uma empresa em vantagem em recursos e mercado tende a ser superior na dimensão financeira. Desta forma a única empresa que verificou este fator foi a Arezzo. De mesmo modo para verificação da referida teoria seria coerente que existisse correlação entre os rankings das diferentes dimensões, o que não se verificou. Assim conclui-se que a vantagem competitiva em recursos e em mercado de empresas do setor têxtil do Brasil não contribui para superioridade no desempenho financeiro das empresas.
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Ecodesign of large-scale photovoltaic (PV) systems with multi-objective optimization and Life-Cycle Assessment (LCA)Perez Gallardo, Jorge Raúl 25 October 2013 (has links) (PDF)
Because of the increasing demand for the provision of energy worldwide and the numerous damages caused by a major use of fossil sources, the contribution of renewable energies has been increasing significantly in the global energy mix with the aim at moving towards a more sustainable development. In this context, this work aims at the development of a general methodology for designing PV systems based on ecodesign principles and taking into account simultaneously both techno-economic and environmental considerations. In order to evaluate the environmental performance of PV systems, an environmental assessment technique was used based on Life Cycle Assessment (LCA). The environmental model was successfully coupled with the design stage model of a PV grid-connected system (PVGCS). The PVGCS design model was then developed involving the estimation of solar radiation received in a specific geographic location, the calculation of the annual energy generated from the solar radiation received, the characteristics of the different components and the evaluation of the techno-economic criteria through Energy PayBack Time (EPBT) and PayBack Time (PBT). The performance model was then embedded in an outer multi-objective genetic algorithm optimization loop based on a variant of NSGA-II. A set of Pareto solutions was generated representing the optimal trade-off between the objectives considered in the analysis. A multi-variable statistical method (i.e., Principal Componet Analysis, PCA) was then applied to detect and omit redundant objectives that could be left out of the analysis without disturbing the main features of the solution space. Finally, a decision-making tool based on M-TOPSIS was used to select the alternative that provided a better compromise among all the objective functions that have been investigated. The results showed that while the PV modules based on c-Si have a better performance in energy generation, the environmental aspect is what makes them fall to the last positions. TF PV modules present the best trade-off in all scenarios under consideration. A special attention was paid to recycling process of PV module even if there is not yet enough information currently available for all the technologies evaluated. The main cause of this lack of information is the lifetime of PV modules. The data relative to the recycling processes for m-Si and CdTe PV technologies were introduced in the optimization procedure for ecodesign. By considering energy production and EPBT as optimization criteria into a bi-objective optimization cases, the importance of the benefits of PV modules end-of-life management was confirmed. An economic study of the recycling strategy must be investigated in order to have a more comprehensive view for decision making.
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