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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.
141

Predição da estrutura de proteínas off-lattice usando evolução diferencial multiobjetivo adaptativa

Venske, Sandra Mara Guse Scós 28 March 2014 (has links)
Fundação Araucária / A Predição da Estrutura das Proteínas, conhecida como PSP (Protein Structure Prediction) pode ser considerada um dos problemas mais desafiadores da Bioinformática atualmente. Quando uma proteína está em seu estado de conformação nativa, a energia livre tende para um valor mínimo. Em geral, a predição da conformação de uma proteína por métodos computacionais é feita pela estimativa de dois valores de energia livre que são provenientes das interações intra e intermoleculares entre os átomos. Alguns estudos recentes indicam que estas interações estão em conflito, justificando o uso de abordagens baseadas em otimização multiobjetivo para a solução do PSP. Neste caso, a otimização destas energias é realizada separadamente, diferente da formulação mono-objetivo que considera a soma das energias. A Evolução Diferencial (ED) é uma técnica baseada em Computação Evolucionária e representa uma alternativa interessante para abordar o PSP. Este trabalho busca desenvolver um otimizador baseado no algoritmo de ED para o problema da Predição da Estrutura de Proteínas multiobjetivo. Este trabalho investiga ainda estratégias baseadas em parâmetros adaptativos para a evolução diferencial. Nicialmente avalia-se uma abordagem simples baseada em ED proposta para a solução do PSP. Uma evolução deste método que incorpora conceitos do algoritmo MOEA/D e adaptação de parâmetros é testada em um conjunto de problemas benchmark de otimização multiobjetivo. Os resultados preliminares obtidos para o PSP (para seis proteínas reais) são promissores e aqueles obtidos para o conjunto benchmark colocam a abordagem proposta como candidata para otimização multiobjetivo. / Protein Structure Prediction (PSP) can be considered one of the most challenging problems in Bioinformatics nowadays. When a protein is in its conformation state, the free energy is minimized. Evaluation of protein conformation is generally performed based on two values of the estimated free energy, i.e., those provided by intra and intermolecular interactions among atoms. Some recent experimental studies show that these interactions are in conflit, justifying the use of multiobjective optimization approaches to solve PSP. In this case, the energy optimization is performed separately, different from the mono-objective optimization which considers the sum of free energy. Differential Evolution (DE) is a technique based on Evolutionary Computation and represents an interesting alternative to solve multiobjective PSP. In this work, an optimizer based on DE is proposed to solve the PSP problem. Due to the great number of parameters, typical for evolutionary algorithms, this work also investigates adaptive parameters strategies. In experiments, a simple approach based on ED is evaluated for PSP. An evolution for this method, which incorporates concepts of the MOEA/D algorithm and parameter adaptation techniques is tested for a set of benchmarks in the multiobjective optimization context. The preliminary results for PSP (for six real proteins) are promising and those obtained for the benchmark set stands the proposed approach as a candidate to the state-of-art for multiobjective optimization.
142

Avaliação de desempenho multicritério como apoio à gestão da diretoria de pesquisa e pós-graduação da Universidade Tecnológica Federal do Paraná, Câmpus Pato Branco: uma perspectiva construtivista / Multicriteria performance evaluation to support the management of the research and postgraduate board of the Federal Technological University of Paraná, Campus Pato Branco: a constructivist perspective

Defaci, Ludmila 28 June 2017 (has links)
A presente dissertação tem como objetivo construir um modelo singular de avaliação de desempenho para atender a Diretoria de pesquisa e pós-graduação da Universidade Tecnológica Federal do Paraná, Câmpus de Pato Branco, utilizando a visão da MCDA-C –Metodologia Multicritério de Apoio à Decisão Construtivista, levando-se em consideração as percepções do decisor por meio dessa metodologia.A pesquisa caracteriza-se como exploratória, descritiva e quali-quantitativa. Os instrumentos utilizados para a coleta e análise dos dados são: Knowledge Development Process- Constructivist (Proknow-C) e metodologia MCDA-C. Em relação ao Proknow-C, esse processo permitiu selecionar 15 artigos internacionais e 15 artigos nacionais alinhados ao tema, tendo como principais resultados: (i) a análise bibliométrica permitiu identificar os principais autores, artigos e periódicos; (ii) a análise sistêmica permitiu chegar aos seguintes resultados: a) os modelos de avaliação de desempenho propostos e/ou aplicados nas pesquisas não demonstram preocupação em desenvolver um modelo singular, específico para o contexto que lhe deu origem, ou o que é importante medir segundo os valores do decisor; b) verificou-se que a maioria dos modelos realiza a mensuração, porém, não realiza a integração dos critérios; c) a maioria dos modelos permitiram diagnosticar os pontos fortes e fracos dos contextos avaliados; d) os modelos demonstraram preocupação em propor ações para gerar ações de aperfeiçoamento, destacando-se o portfólio internacional. Por meio da MCDA-C foram obtidos os seguintes resultados: (i) identificação de 64 elementos primários de avaliação (EPAs)os quais foram explorados e discutidos originando 89 conceitos orientados à ação; (ii) constatação de duas grandes dimensões de preocupação do decisor - qualidade e gestão, sendo que a primeira grande área está relacionada à pesquisa e pós-graduação stricto sensu, aos grupos de pesquisa e à pós-graduação lato sensu; e a segunda está relacionada à imagem e aos processos internos; (iii) criação de 5 mapas de relações meios e fins, nos quais, conforme as dimensões identificadas,as preocupações operacionais (conceitos meios) e as preocupações estratégicas (conceitos fins)foram alocadas; (iv)formulação de 51 indicadores de desempenho com a participação integral do decisor; (v) construção dos descritores por meio de escalas ordinais e forma determinados os níveis de referência para cada indicador; (vi) transformação das ordinais em escalas cardinais (quantitativas); (vii) realização da análise de independência; (viii) construção das funções de valor; e (ix) determinação das taxas de substituição.Concluise a partir da filiação teórica adotada, que a estruturação do modelo de avaliação de desempenho proposto será útil para dar apoio à gestão da diretoria de pesquisa e pós-graduação da UTFPR, Câmpus de Pato Branco, bem comoo cotejamento dos indicadores da literatura com o modelo desenvolvido contribui teoricamente para a literatura. / The present work aims to build a unique model of performance evaluation to meet the Research and Graduate Directorate of the Federal Technological University of Paraná, Pato Branco Câmpus, using the MCDA-C vision - Multicriteria Decision Support Methodology Constructivist, taking into account the perceptions of the decision maker through this methodology. The research is characterized as exploratory, descriptive and qualitativequantitative. The instruments used for data collection and analysis are: Knowledge Development Process- Constructivist (Proknow-C) and MCDA-C methodology.In relation to Proknow-C, this process allowed the selection of 15 international articles and 15 national articles aligned to the theme, with the following main results: (i) bibliometric analysis allowed to identify the main authors, articles and periodicals; (ii) the systemic analysis allowed the following results to be obtained: a) the performance evaluation models proposed and/or applied in the researches do not show concern in developing a singular model, specific to the context that gave rise to it, or what is important Measure according to the values of the decision maker; b) it was verified that most of the models carry out the measurement, however, it does not integrate the criteria; c) most of the models allowed to diagnose the strengths and weaknesses of the contexts evaluated; d) the models showed concern in proposing actions to generate improvement actions, highlighting the international portfolio.The following results were obtained through MCDA-C: (i) identification of 64 primary evaluation elements (EPAs) which were explored and discussed, giving rise to 89 action-oriented concepts; (ii) finding two major dimensions of decision-maker concern - quality and management, the first large area of which is related to the research and graduate studies stricto sensu, to the research groups and to the lato sensu graduate studies; And the second is related to the image and internal processes; (iii) creation of 5 maps of means and ends relationships, in which, according to the identified dimensions, operational concerns (means concepts) and strategic concerns (concepts ends) were allocated; (iv) formulation of 51 performance indicators with the full participation of the decision maker; (v) construction of the descriptors by means of ordinal scales and form the reference levels for each indicator; (vi) transformation of ordinals into cardinal (quantitative) scales; (vii) conducting the independence analysis; (viii) construction of value functions; and (ix) determination of replacement rates. It is concluded from the theoretical affiliation adopted that the structuring of the proposed performance evaluation model will be useful to support the management of the UTFPR research and graduate board, Câmpus de Pato Branco, as well as the comparison of the indicators of the Literature with the developed model contributes theoretically to the literature.
143

Modèles et méthodes pour la gestion logistique optimisée dans le domaine des services et de la santé / Models and optimization approaches for logistic problems in health care systems and services sector

Ait Haddadene, Syrine Roufaida 30 September 2016 (has links)
Cette thèse aborde le problème de tournées de véhicules (VRP) intégrant des contraintes temporelles : fenêtres de temps (TW), synchronisation (S) et précédence (P), appliqué au secteur de soins à domicile, donnant le VRPTW-SP. Il s’agit d’établir un plan de visite journalier des soignants, aux domiciles des patients ayant besoin d’un ou plusieurs services. Tout d’abord, nous avons abordé ce problème sous angle mono-objectif. Ensuite, le cas bi-objectif est considéré. Pour la version mono-objectif, un Programme Linéaire à Variables Mixtes Entières (PLME), deux heuristiques constructives, deux procédures de recherches locales et trois métaheuristiques à base de voisinages sont proposés : une procédure de recherche constructive adaptative randomisée (GRASP), une recherche locale itérée (ILS) et une approche hybride (GRASP × ILS). Concernant le cas bi-objectif, différentes versions de métaheuristiques évolutionnaires multi-objectifs sont proposées, intégrant différentes recherches locales : l’algorithme génétique avec tri par non-dominance version 2 (NSGAII), une version généralisée de ce dernier avec démarrages multiples (MS-NSGAII) et une recherche locale itérée avec tri par non-dominance (NSILS). Ces algorithmes ont été testés et validés sur des instances adaptées de la littérature. Enfin, nous avons étendu le VRPTW-SP sur un horizon de planification, donnant le VRPTW-SP multi-période. Pour résoudre cette extension, un PLME ainsi qu’une matheuristique sont proposés / This work addresses the vehicle routing problem (VRP) including timing constraints: time windows (TW), synchronization (S) and precedence (P), applied in Home Health Care sector; giving the VRPTW-SP. This problem consists in establishing a daily caregivers planning to patients' homes asking for one or several services. We have started by considering the problem as a single objective case. Then, a bi-objective version of the problem is introduced. For solving the single-objective problem, a Mixed Integer Linear Program (MILP), two constructive heuristics, local search procedures and three local search based metaheuristics are proposed : a Greedy Randomized Adaptive Search procedure (GRASP), an Iterated Local Search (ILS) and a hybrid approach (GRASP × ILS). Regarding the bi-objective VRPTW-SP, different versions of multi-objective evolutionary algorithm, including various local research strategies are proposed: the Non-dominated Sorting Genetic Algorithm version 2 (NSGAII), a generalized version of this latter with multiple restarts (MS-NSGAII) and an Iterated Local Search combined with the Non-dominated Sorting concept (NSILS). All these algorithms have been tested and validated on appropriate instances adapted from the literature. Finally, we extended the VRPTW-SP on a multi-period planning horizon and then proposed a MILP and a matheuristic approach
144

On the use of multicriteria ranking methods in sorting problems / Utilisation des méthodes de rangements multicritères dans les problèmes de tri

Nemery De Bellevaux, Philippe 29 November 2008 (has links)
Notre thèse est consacrée à l’étude des méthodes de rangements multicritères dans le cadre de la problématique de tri.<p> <p>Dans un problème de tri une personne, appelée décideur, désire assigner un objet, appelé action, à des catégories prédéfinies. Des problèmes de tri surgissent régulièrement dans la vie de tous les jours. Par exemple, un médecin ausculte son patient et sur base des symptômes observés, il assigne son patient à une catégorie de pathologies. Ainsi, le médecin peut prescrire un traitement approprié. Par ailleurs, on catégorise les cyclones tropicaux en fonction de leur vitesse, pression superficielle et de la hauteur de marée. En fonction de la catégorie du cyclone, des dégâts éventuels peuvent être prédits et des mesures de protection adéquates devront être prises. <p> <p>Dans un problème de tri, un décideur regroupe ainsi les actions qu’il considère similaires, à des fins descriptives, organisationnelles ou préventives. Nous supposerons en outre que le décideur exprime une relation de préférence entre les classes préalablement définies.<p> <p>D’autre part, les méthodes de rangement permettent de ranger les actions de la meilleure à la moins bonne. Nul étudiant ne peut nier l’existence des " rankings " d’universités. Une société ordonne les candidats à l’issue d’un entretien d’embauche. Une société désire par ailleurs établir des partenariats avec les fournisseurs les plus performants. Nous sommes tous confrontés à cette tâche délicate de ranger les actions de la meilleure à la moins bonne. Les méthodes d’aide à la décision proposent des techniques permettant à un décideur d’obtenir un rangement d’actions.<p> <p>L’objectif de cette thèse est d’étudier la possibilité de résoudre des problèmes de tri à l’aide de méthodes de rangement. L’approche adoptée est de ranger une action particulière par rapport à des normes ou profils définissant les catégories. L’assignation de l’action sera dès lors basée sur sa position dans ce rangement particulier.<p> <p>Quelles sont les hypothèses nécessaires pour un tel modèle ?Ces méthodes présentent-elles un biais ou ont-elles d’autres avantages par rapport aux méthodes de tri existantes? Est-il préférable de modéliser les catégories à l’aide de critères même si celles-ci ne présentent pas de relation de préférence ?Dans cette thèse nous donnerons des premiers éléments de réponse en développant de nouvelles méthodes de tri basées sur des méthodes de rangement existantes.<p> <p><p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
145

Multi-criteria decision aiding model for the evaluation of agricultural countermeasures after an accidental release of radionuclides to the environment

Turcanu, Catrinel 31 October 2007 (has links)
Multi-criteria decision aid has emerged from the operational research field as the answer given to a couple of important questions encountered in complex decisions problems. Firstly, as decision aiding tools, such methods do not replace the decision maker with a mathematical model, but support him to construct his solution by describing and evaluating his options. Secondly, instead of using a unique criterion capturing all aspects of the problem, in the multi-criteria decision aid methods one seeks to build multiple criteria, representing several points of view. <p>This work explores the application of multi-criteria decision aid methods for optimising food chain countermeasure strategies after a radioactive release to the environment. <p>The core of the thesis is dedicated to formulating general lines for the development of a multi-criteria decision aid model. This includes the definition of potential actions, construction of evaluation criteria and preference modelling and is essentially based on the results of a stakeholders’ process. The work is centred on the management of contaminated milk in order to provide a concrete focus and because of its importance as an ingestion pathway in short term after an accident.<p>Among other issues, the public acceptance of milk countermeasures as a key evaluation criterion is analysed in detail. A comparison of acceptance based on stochastic dominance is proposed and, based on that, a countermeasures’ acceptance ranking is deduced.<p>In order to assess “global preferences” taking into account all the evaluation criteria, an ordinal method is chosen. This method allows expressing the relative importance of criteria in a qualitative way instead of using, for instance, numerical weights. Some algorithms that can be used for robustness analysis are also proposed. This type of analysis is an alternative to sensitivity analysis in what concerns data uncertainty and imprecision and seeks to determine how and if a model result or conclusion obtained for a specific instance of a model’s parameters holds over the entire domain of acceptable values for these parameters.<p>The integrated multi-criteria decision aid approach proposed makes use of outranking and interactive methodologies and is implemented and tested through a number of case studies and prototype tools. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
146

Praktické využití metod vícekriteriálního rozhodování pro zhodnocení obchodních řetězců, kategorie sýry, v České republice / Practical use of multiple criteria decision making methods to evaluate commercial chains, cheese category, in Czech Republic

Slavík, Vladimír January 2008 (has links)
The subject of diploma thesis is the evaluation of commercial chains, cheese category, in Czech Republic. The methodology is based on the multicriteria rating of alternatives. In the evaluation of commercial chains may take into account the large number of criteria are used, here are 26, which evaluates 14 alternatives (stores). To evaluate the commercial chains are used preferences of general public and experts. The main objective of the diploma thesis is to determine which store is the best for customers (general public) and for professionals, and then to compare the results.Secondary objective is to explore the possibility of using the multicriteria rating of alternatives methods in praxis.
147

Moderní metody a nástroje pro podporu manažerského rozhodování / Modern Methods and Tools to Support Managerial Decision

Krčil, Jakub January 2012 (has links)
This master's thesis is focused on modern methods and tools to support managerial decision-making. The first part of this thesis introduces the basic characteristics related to the management and managerial decision-making that are subsequently extended to the area of modeling, simulation, optimization and multi-criteria decision making. It also outlines the relationship between the managerial decision-making tasks. The second part introduces practical examples which show the connection of these areas. Specifically, they are a colony of ants, traveling salesman problem, a tool AnyLogic, analytic hierarchy process and simulation HealthBound. The thesis is further supplemented by an appropriate software tools to support multi-criteria decision making.
148

電子商務環境供應鏈供需互動模式之研究 / The Interactive Supply-Demand Model for Supply Chain in Electronic Commerce

施穎偉, Daniel Ying-wei Shee Unknown Date (has links)
在電子商務的環境中,透過資訊科技的使用與通訊網路的連結,將會有愈來愈多的產品或服務需求者透過新興的電子化媒體 (如網際網路) 來尋找可行的交易互動夥伴,進而完成交易。因此,交易結構□每一份子間的互動關係,將面臨新的衝擊與挑戰。而納入電子商務觀念的供應鏈管理,將是以資訊科技與通訊技術為基礎的新領域,在此一領域中,供應鏈可以簡單地概念化成三部份:即產品/服務的供給者 (賣方)、產品/服務的需求者或是消費者 (買方)、及提供兩者溝通服務的資訊服務提供者。而在三者間,除了存在著生產與配送過程中既有的物料流/產品流、服務流及完成交易所必須的金流之外,更重要的是還有提供控制機能的資訊流。如何有效地管理與利用資訊流便成為供應鏈管理成功與否的關鍵性因素,而企業也因此產生了對於資訊服務的需求。 因此,本論文的目的在於發展出一個完整的研究體系,以針對傳統供應鏈中之供需雙方與資訊服務業之間的關係,發展出一個供需互動模式,以使電子商務環境中資訊服務的供需雙方能夠據此制定重要的決策與策略。此一體系包含了以下三個子體系:概念體系、評估體系、以及規劃體系。在概念體系的部份,本研究將透過文獻探討,針對供應鏈中的供需者 (可被視為資訊服務的需求者) 與資訊服務提供者,發展出一個整合的概念性互動模式,此一模式將解釋各個體之目標與其行為屬性,而這些目標與屬性也將成為後續評估及規劃體系發展的基礎。而後續兩個體系的發展,將以資訊服務的供需互動為研究主體。就評估體系而言,本研究將分別使用加法型 (層級分析法) 與非加法型 (模糊積分法) 方法來發展評選資訊服務提供者的多準則決策模式。而根據上述的結果,決策者便可針對其手邊現有的可選擇方案,來進行評選。一旦評選結果確定之後,決策者便可與其進行後續的供需互動。至於規劃體系的部份,則是要分析供需雙方如何根據自身的目標與資源限制,經由資訊的分享與交換,與所選取的夥伴進行互動。根據供需關係的型態及供需互動的主導者這兩個分類的標準,本研究將供需互動分成四種不同的狀況來探討。而透過模糊二階多目標規劃模式與多階段解題流程圖的應用,我們可以分析供需單位間如何透過資訊的交換以進行互動,並解釋互動所可能出現的結果,亦即失敗或成功。最後,本研究也將使用一個簡例來說明模式的可用性。 第一章 緒論…………………………………………… 1 第一節 研究動機與背景………………………… 1 第二節 研究目的………………………………… 3 第三節 研究方法與發展流程…………………… 5 第四節 論文結構與內容………………………… 6 第二章 文獻探討……………………………………… 7 第一節 電子商務………………………………… 7 壹、電子商務之定義……………………………. 7 貳、電子市場……………………………………. 12 第二節 供應鏈管理……………………………… 15 壹、供應鏈管理之定義………………………… 15 貳、關係的管理與分析………………………...… 17 參、買賣雙方之供需關係………………………... 21 肆、資訊服務提供者之中介……………………... 24 第三節 個體之目標與行為……………………… 29 壹、供應鏈管理之整體目標……………………... 29 貳、供給者 (賣方) 之立場……………………… 32 參、需求者 (買方) 之立場……………………… 35 肆、資訊服務提供者之立場…………………… 39 第三章 研究模式與方法……………………………… 49 第一節 研究模式………………………………. 49 壹、研究定位與個體定義………………………. 49 貳、供需互動模式………………………………. 51 參、研究範圍與分類架構………………………. 52 第二節 研究類型與步驟………………………… 54 第三節 評估方法論……………………………… 58 壹、因子分析……………………………………... 58 貳、加法型多準則評估…………………………. 59 參、非加法型多準則評估………………………. 61 肆、方案績效值的取得………………………… 63 第四節 規劃方法論……………………………… 70 壹、多目標規劃法…………………………… 70 貳、二階規劃法…………………………………. 73 第四章 評估面之研究 – 資訊服務提供者之評選…… 78 第一節 樣本特徵與資訊服務之使用現況……… 78 第二節 評選資訊服務提供者之準則分析……… 81 壹、評選準則之敘述統計分析………………… 81 貳、評選準則之因子分析……………………… 82 參、後續之效度驗證程序……………………… 90 第三節 多準則評估與決策體系之建立………… 93 壹、加法型多準則評估 – 層級分析法………… 93 貳、非加法型多準則評估 – 模糊積分法……… 97 參、實例說明與比較……………………………. 99 第五章 規劃面之研究 – 供需互動模式之發展…...….. 103 第一節 各種供需互動之說明…………………. 103 第二節 供需互動模式之發展………………… 106 壹、問題特性與解題流程……………………… 106 貳、互動規劃模式之建立……………………… 107 參、不同關係型態對互動過程的影響………… 113 第三節 簡例說明……………………………… 117 壹、背景說明…………………………………… 117 貳、問題求解過程說明………………………… 118 參、討論………………………………………… 125 第六章 結論與建議…………………………………… 127 第一節 結論……………………………………… 127 第二節 研究限制與困難………………………… 129 第三節 未來發展方向…………………………… 130 參考文獻………………………………………………… 131 附錄一………………………………………………………… 141 附錄二………………………………………………………… 145 附錄三………………………………………………………… 150 附錄四………………………………………………………… 153 附錄五………………………………………………………… 155 附錄六………………………………………………………… 163 附錄七………………………………………………………… 165 博士候選人簡歷……………………………………………… 172 / In the environment of Electronic Commerce (EC), there are more and more demanders of products or services looking for available interactive partners of transaction through the burgeoned electronic media (such as the Internet), who then complete transactions with the use of information technology and the connection of communication networks. Therefore, the interactive relationship between each member in the transaction structure will face new poundings and challenges. And the supply chain (SC) management, which fits into the notion of EC, will be a new field based on information technology and communication infrastructure. Within this field, the SC can be simply conceptualized into three parts: (1) Those act as the suppliers of products and services (the sellers), (2) The demanders or consumers of products and services (the buyers) and (3) the information service provider (ISP) which provides the information service for both parties. Among these three parties, in addition to the material/product flow and service flow existed in the production and distribution processes together with the financial flow required of accomplishing transactions, what is more important is the information flow that provides control function. Thus, how to effectively manage and use information flow becomes a key factor for successful SC management. As a result, the needs from enterprises for information service arise. This dissertation aims to establish a complete research system which helps develop an interactive supply-demand model for SC in EC, especially focusing on the relationship between the demanders and suppliers of information service. The research system includes three sub-systems: system of conceptualization, system of evaluation and system of planning. The system of conceptualization develops an integrated conceptual model to depict the interactive supply-demand relationship within SC. This model explains the objectives and the behavioral attributes of every individual, which then become the foundation of follow-up development of the systems of evaluation and planning. As for system of evaluation, this paper uses both additive (Analytic Hierarchy Process) and non-additive methods (Fuzzy Integral) to develop the multiple criteria decision making model for evaluating and selecting ISPs. In accordance with the results above, decision-makers are able to evaluate and select from alternatives on hand. Once the evaluation result is confirmed, decision-makers can proceed with the follow-up supply-demand interaction. As for the planning system, analysis of how supplier and demander of information service interact with each other according to their objectives and resource constraints is carried out. This dissertation also divides the supply-demand interaction into four different situations according to the type of relationship and the dominance. Through the application of fuzzy bi-level multiple objective programming (fuzzy BLMOP) technique and the multi-stage problem solving flow chart, we can analyze how the supply and demand units interact with each other by exchanging information and the possible outcomes of interactions can be explained. Finally, this dissertation illustrates the applicability of the fuzzy BLMOP model with a simple example.
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Ecodesign of large-scale photovoltaic (PV) systems with multi-objective optimization and Life-Cycle Assessment (LCA) / Écoconception de systèmes photovoltaïques (PV) à grande échelle par optimisation multi-objectif et Analyse du Cycle de Vie (ACV)

Perez Gallardo, Jorge Raúl 25 October 2013 (has links)
En raison de la demande croissante d’énergie dans le monde et des nombreux dommages causés par l’utilisation des énergies fossiles, la contribution des énergies renouvelables a augmenté de manière significative dans le mix énergétique global dans le but de progresser vers un développement plus durable. Dans ce contexte, ce travail vise à l’élaboration d’une méthodologie générale pour la conception de systèmes photovoltaïques, basée sur les principes d’écoconception, en tenant compte simultanément des considérations technico-économiques et environnementales. Afin d’évaluer la performance environnementale des systèmes PV, une technique d’évaluation environnementale basée sur l’Analyse du Cycle de Vie (ACV) a été utilisée. Le modèle environnemental a été couplé d’une manière satisfaisante avec le modèle de conception d’un système PV connecté au réseau pour obtenir un modèle global, apte à un traitement par optimisation. Le modèle de conception du système PV résultant a été développé en faisant intervenir l’estimation du rayonnement solaire reçu dans une zone géographique concernée, le calcul de la quantité annuelle d’énergie produite à partir du rayonnement solaire reçu, les caractéristiques des différents composants et l’évaluation des critères technico-économiques à travers le temps de retour énergétique et le temps de retour sur investissement. Le modèle a ensuite été intégré dans une boucle d’optimisation multi-objectif externe basée sur une variante de l’algorithme génétique NSGA-II. Un ensemble de solutions du Pareto a été généré représentant le compromis optimal entre les différents objectifs considérés dans l’analyse. Une méthode basée sur une Analyse en Composantes Principales (ACP) est appliquée pour détecter et enlever les objectifs redondants de l’analyse sans perturber les caractéristiques principales de l’espace des solutions. Enfin, un outil d’aide à la décision basé sur M- TOPSIS a été utilisé pour sélectionner l’option qui offre un meilleur compromis entre toutes les fonctions objectifs considérées et étudiées. Bien que les modules photovoltaïques à base de silicium cristallin (c-Si) ont une meilleure performance vis-à-vis de la production d’énergie, les résultats ont montré que leur impact environnement est le plus élevé des filières technologiques de production de panneaux. Les technologies en « couches minces » présentent quant à elles le meilleur compromis dans tous les scénarios étudiés. Une attention particulière a été accordée aux processus de recyclage des modules PV, en dépit du peu d’informations disponibles pour toutes les technologies évaluées. La cause majeure de ce manque d’information est la durée de vie relativement élevée des modules photovoltaïques. Les données relatives aux procédés de recyclage pour les technologies basées sur CdTe et m-Si sont introduites dans la procédure d’optimisation par l’écoconception. En tenant compte de la production d’énergie et du temps de retour sur énergie comme critères d’optimisation, l’avantage de la gestion de fin de vie des modules PV a été confirmé. Une étude économique de la stratégie de recyclage doit être considérée et étudiée afin d’avoir une vision plus globale pour la prise de décision. / 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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Écoconception de procédés : approche systémique couplant modélisation globale, analyse du cycle de vie et optimisation multiobjectif / Eco-design of chemical processes : an integrated approach coupling process modeling, life cycle assessment and multi-objective optimization

Morales Mendoza, Luis Fernando 04 December 2013 (has links)
L’objectif de ce travail est de développer un cadre méthodologique et générique d’éco-conception de procédés chimiques couplant des outils de modélisation et de simulation traditionnels de procédés (HYSYS, COCO, ProSimPlus et Ariane), d’Analyse du Cycle de Vie (ACV), d’optimisation multiobjectif basée sur des Algorithmes Génétiques et enfin des outils d’aide à la décision multicritère (ELECTRE, PROMETHEE, M-TOPSIS). Il s’agit de généraliser, d’automatiser et d’optimiser l’évaluation des impacts environnementaux au stade préliminaire de la conception d’un procédé chimique. L’approche comprend trois étapes principales. Les deux premières correspondent d’une part aux phases d’analyse de l’inventaire par calcul des bilans de matière et d’énergie et d’autre part à l’évaluation environnementale par ACV. Le problème du manque d’information ou de l’imprécision dans les bases de données classiques en ACV pour la production d’énergie notamment sous forme de vapeur largement utilisée dans les procédés a reçu une attention particulière. Une solution proposée consiste à utiliser un simulateur de procédés de production d’utilités (Ariane, ProSim SA) pour contribuer à alimenter la base de données environnementale en tenant compte de variations sur les conditions opératoires ou sur les technologies utilisées. Des sous-modules « énergie » sont ainsi proposés pour calculer les émissions relatives aux impacts liés à l’utilisation de l’énergie dans les procédés. La troisième étape réalise l’interaction entre les deux premières phases et l’optimisation multi-objectif qui met en jeu des critères économiques et environnementaux. Elle conduit à des solutions de compromis le long du front de Pareto à partir desquelles les meilleures sont choisies à l’aide de méthodes d’aide à la décision. L’approche est appliquée à des procédés de production continus : production de benzène par hydrodéalkylation du toluène HDA et production de biodiesel à partir d’huiles végétales. Une stratégie à plusieurs niveaux est mise en oeuvre pour l'analyse de l'optimisation multi-objectif. Elle est utilisée dans les deux cas d'étude afin d'analyser les comportements antagonistes des critères. / The objective of this work is to propose an integrated and generic framework for eco-design coupling traditional modelling and flowsheeting simulation tools (HYSYS, COCO, ProSimPlus and Ariane), Life Cycle Assessment, multi-objective optimization based on Genetic Algorithms and multiple criteria decision-making methods MCDM (Multiple Choice Decision Making, such as ELECTRE, PROMETHEE, M-TOPSIS) that generalizes, automates and optimizes the evaluation of the environmental criteria at earlier design stage. The approach consists of three main stages. The first two steps correspond respectively to process inventory analysis based on mass and energy balances and impact assessment phases of LCA methodology. Specific attention is paid to the main issues that can be encountered with database and impact assessment i.e. incomplete or missing information, or approximate information that does not match exactly the real situation that may introduce a bias in the environmental impact estimation. A process simulation tool dedicated to production utilities, Ariane, ProSim SA is used to fill environmental database gap, by the design of specific energy sub modules, so that the life cycle energy related emissions for any given process can be computed. The third stage of the methodology is based on the interaction of the previous steps with process simulation for environmental impact assessment and cost estimation through a computational framework. The use of multi-objective optimization methods generally leads to a set of efficient solutions, the so-called Pareto front. The next step consists in identifying the best ones through MCDM methods. The approach is applied to two processes operating in continuous mode. The capabilities of the methodology are highlighted through these case studies (benzene production by HDA process and biodiesel production from vegetable oils). A multi-level assessment for multi-objective optimization is implemented for both cases, the explored pathways depending on the analysis and antagonist behaviour of the criteria.

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