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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.
11

Prise en compte de la valeur ajoutée client dans la spécification des exigences / A prescriptive approach to derive value-based requirements specification : application to the requirements engineering of commercial aircraft

Zhang, Xinwei 30 January 2012 (has links)
Ces dernières années, la conception de produit vise de plus en plus à remettre le client aucentre du processus de développement. De nouvelles méthodes et outils ont permis de formaliser nonseulement l’identification des besoins et des attentes du client mais également leur transformation enexigences. Cependant, malgré les progrès récemment apparus dans ce domaine, la notion de valeurperçue par le client qui est associée au produit reste faiblement considérée durant le développement duproduit alors que la perception de cette valeur par le client va jouer un rôle clé au moment du choix duproduit.Dans cette thèse, nous proposons une approche normative visant l’intégration de la notion devaleur du produit dans le processus d’établissement des exigences. Un état de l’art présente lesconcepts et les pratiques impliqués dans le déploiement de la fonction de qualité, étroitement liée auprocessus de spécification des exigences basé sur la valeur. Ces concepts sont relatifs aux notionsd’objectifs, de modèles de la valeur, de fonctions d’utilité multi attributs et de hiérarchie et de réseauxd’objectifs.Notre approche se déroule en 4 étapes : (1) identifier et structurer les objectifs à partir del’expression des attentes du client, (2) spécifier les attributs de la valeur perçue par le client etconstruire un modèle de la valeur client, (3) transformer les objectifs en exigences pour construire unmodèle global de la valeur produit et (4) dériver ce modèle global en un modèle de la valeur pourchaque composant du produit. Cette approche permet ainsi de prendre en compte explicitement lavaleur produit perçue par le client en l’intégrant dans les phases de développement, ce qui favorise uneconception proactive dirigée par la valeur.Nous l’illustrons sur un exemple d’avion de ligne développé en Vanguard Studio. Cet exemplea été élaboré par l’ensemble des partenaires au cours du projet Européen IST CRESCENDO et sert decas-test pour ce projet / Recently customer-based product development is becoming a popular paradigm. Customer needsand expectations are identified and transformed into requirements in systematic processes for productdesign with the help of various methods and tools. However, in many cases, these approaches fail tofocus on the perceived value that is crucially important when customers make the decision ofpurchasing a product. The requirements specification derived from these approaches are typicallyvalue-implicit.In this thesis, a prescriptive approach to derive value-based requirements specification is proposedby integrating the concept of value into the house of quality of quality function deployment. Anintegrated set of theories, methods and concepts is introduced in order to mitigate the sevenmethodological problems of house of quality regarding to establishing appropriate value-basedrequirements specification. The foundations of the approach include concepts of objective, valuemodel and consequence model, methods of means-ends objectives network, fundamental objectiveshierarchy, response surface methodology and value-driven design, and theory of multi-attribute utilitytheory. The procedure of the approach is a four-step process: (1) identify and structure objectives frominitial customer statements of expectations, (2) specify attributes and construct customer value model,(3) transform fundamental objectives into engineering characteristics to construct system value model,and (4) derive component value models from system value model. Through this procedure, initialcustomer statements can be reasonably derived into customer value model, system value model andcomponent value model. The benefits of the approach are that it enables (1) reasonably qualifying andquantifying customer value, and performing value modeling and simulation, (2) perceived customervalue being subsequently used reactively for design evaluation, and proactively for value-drivendesign.The approach is applied in the context of a European Community’s R&D project CRESCENDO tohelp constructing airlines’ group value model for commercial aircraft development. This applicationfocuses on the first two-steps of the approach, and the value models are implemented in businesssoftware Vanguard Studio
12

Development of a GIS and model-based method for optimizing the selection of locations for drinking water extraction by means of riverbank filtration

Zhou, Yan 12 January 2021 (has links)
The lack of safe drinking water worldwide has drawn the attention of decision makers to riverbank filtration (RBF) for its many advantages in purifying surface water. This study provides an overview of the hydrogeologic, fluvial, and environmental influences on the performance of RBF systems and aims to develop a model for RBF site selection. Using multi-attribute utility theory (MAUT), this study structured the RBF siting problem and assessed a multiplicative utility function for the decision maker. In a case study, geostatistical methods were used to acquire the necessary data and geographic information systems (GIS) were used to screen sites suitable for RBF implementation. Those suitable sites were then evaluated and ranked using the multi-attribute utility model. The result showed that sites can be identified as most preferred among the selected suitable sites based on their expected utility values. This study definitively answers the question regarding the capability of MAUT in RBF site selection. Further studies are needed to verify the influences of the attributes on the performance of RBF systems.:Abstract iii Zusammenfassung iv Acknowledgments v Table of Contents vi List of Tables viii List of Figures x Definition of terms xiii 1. Abbreviations xiii 2. Symbols xiii Part I Introduction 1 1. Introduction 2 2. Statement of purpose 2 3. Research questions 3 4. Overview of methodology 3 5. Organization of the dissertation 3 Part II Fundamentals and Literature Review 5 1. The definition of bank filtration 6 2. The Significance of RBF 7 2.1 RBF in drinking water supply 7 2.2 Benefits of RBF for China 14 3. RBF Site Selection 19 3.1 RBF site selection model 20 3.2 Definition of successful RBF sites 24 4. Factors Affecting RBF Site Selection 26 4.1 River hydrology/hydraulics 27 4.2 Geology 28 4.3 Land cover 36 4.4 Well field location 36 4.5 Water quality 37 4.6 Aquifer properties 38 4.7 Distance to river 41 4.8 Riverbed characteristics 43 5. Effect of Clogging on Yield 46 6. Summary 51 Part III Developing a Multi-attribute Utility Model for RBF Site Selection 53 1. Introduction 54 2. Objectives and Attributes 54 3. Assessment of the Utility Function 57 3.1 Investigation of the qualitative preference structure 58 3.2 Assessment of component utility function 62 3.3 Assessment of the scaling constants 63 4. Results 67 5. Discussion 69 6. Summary 74 Part IV Case Study 75 1. Introduction 76 2. Materials and Methods 78 2.1 GIS data collection 78 2.1.1 Geologic data 79 2.1.2 Land cover data 79 2.1.3 Groundwater quality data 80 2.1.4 Aquifer properties data 80 2.1.5 Surface water area data 80 2.1.6 Surface water quality data 81 2.1.7 Streambed material data 81 2.2 Kriging the saturated thickness 91 2.3 Aggregation of all constraint maps 103 3. Results 105 3.1 Kriging 105 3.2 Suitable sites 105 4. Discussion 109 4.1 A discussion of the kriging results 109 4.2 A discussion of the multi-attribute utility model results 117 5. Summary 122 Part V Conclusions and Recommendations 123 1. Conclusion and Recommendation 124 Appendix 1 Environmental quality standards for surface water (GB 3838-2002) 125 Appendix 2 Quality standard for groundwater (GB14848-93) 127 Appendix 3 Explanation to Germany’s RBF site location data 130 Appendix 4 Layer information of drillings 133 Appendix 5 Streambed materials used by Schälchli (1993) 141 Appendix 6 Interview and questionnaires 143 Appendix 7 Surface water area of Jilin City 150 Bibliography 152
13

Simulated Annealing-based Multilink Selection Algorithm in SDN-enabled Avionic Networks

Luong, Doanh K., Ali, Muhammad, Li, Jian-Ping, Asif, Rameez, Abdo, K. 03 November 2021 (has links)
Yes / In this paper, a novel multilink selection framework is developed for different applications with various quality of service (QoS) requirements in avionic systems, based on the multi-attribute decisionmaking model. Two metaheuristic algorithms are proposed to solve this model while optimizing the multilink selection performances. Multilink configuration and multi-homing capabilities are generally required for aircrafts operating in a heterogeneous wireless network environment. The first algorithm, called Analytic Hierarchy Process and Simulated Annealing (AHP-SA), utilises a two-phase process. In Phase one, an analytic hierarchy process (AHP) is used to choose the decision weight factors. Then, in Phase two, a simulated annealing process is applied to select suitable networks, for various service requests, based on the weights obtained from first phase. Further, to improve customer satisfaction, Simulated Annealing algorithm for Simultaneous Weights and Network Selection Optimisation (SA-SWNO) is developed, in which a simulated annealing algorithm is applied to dynamically optimise weight factors of objective functions and the request-to-network assignment matrix. Simulation results demonstrates that both proposed algorithms outperform the commonly used price-based or QoS-based network selection scheme with much higher averaged satisfaction degree and lower computational complexity. / Cockpit NetwOrk CoMmunications Environment Testing (COMET) Project under the European Commission’s Program Clean Sky2 in partnership with the European Aeronautical Industry
14

An Airspace Planning and Collaborative Decision Making Model Under Safety, Workload, and Equity Considerations

Staats, Raymond William 15 April 2003 (has links)
We develop a detailed, large-scale, airspace planning and collaborative decision-making model (APCDM), that is part of an $11.5B, 10-year, Federal Aviation Administration (FAA)-sponsored effort to increase U.S. National Airspace (NAS) capacity by 30 percent. Given a set of flights that must be scheduled during some planning horizon, we use a mixed-integer programming formulation to select a set of flight plans from among alternatives subject to flight safety, air traffic control workload, and airline equity constraints. Novel contributions of this research include three-dimensional probabilistic conflict analyses, the derivation of valid inequalities to tighten the conflict safety representation constraints, the development of workload metrics based on average (and its variance from) peak load measures, and the consideration of equity among airline carriers in absorbing the costs related to re-routing, delays, and cancellations. We also propose an improved set of flight plan cost factors for representing system costs and investigating fairness issues by addressing flight dependencies occurring in hubbed operations, as well as market factors such as schedule convenience, reliability, and the timeliness of connections. The APCDM model has potential use for both tactical and strategic applications, such as air traffic control in response to severe weather phenomenon or spacecraft launches, FAA policy evaluation, Homeland Defense contingency planning, and military air campaign planning. The model is tested to consider various airspace restriction scenarios imposed by dynamic severe weather systems and space launch Special Use Airspace (SUA) impositions. The results from this model can also serve to augment the FAA's National Playbook of standardized flight profiles in different disruption-prone regions of the National Airspace. / Ph. D.
15

Leilões eletrônicos reversos multiatributo : uma abordagem de decisão multicritério como instrumento de agregação de valor aos processos de compras do setor público brasileiro

Menezes, Ronald do Amaral January 2003 (has links)
Made available in DSpace on 2009-11-18T19:01:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2003 / Auctions are secular institutions used in the commercial relationships among individuaIs and organizations. They provi de greater flexibility to the processes of determination of prices and allocation of goods, increasing the space for negotiations among buyers and sellers. In the Internet, they have been used, in a growing way, in B2B and G2B electronic commerce, mostly through the model of reverse auctions. However, its unidimensional aspect reduces the negotiations to the variable price, producing, many times, bad results. In the Brazilian case, the Federal Government launched Comprasnet, an Internet public emarketplace, through which public organizations acquire goods and services from registered suppliers. Considering alI the available bidding modalities, 'Electronic Pregão' stands out, as an unidimensional reverse auction, based on price, through which suppliers dispute for contracts of the public administration. In the present work, the author proposes a multicriteria decision-making approach, based on Multi-attribute Utility Theory, as an alternative for the adoption of multi-attribute reverse auctions, adding value to Brazilian Public Buying Organizations. / Leilões são instituições seculares utilizadas nas relações comerciais entre indivíduos e organizações. Provêem maior flexibilidade aos processos de determinação de preços e alocação de bens, aumentando o espaço para negociações entre compradores e vendedores. Na Internet, têm sido empregados, de maneira crescente, em atividades de comércio eletrônico B2B e G2B, em sua maioria, através da modalidade de leilão reverso. No entanto, seu aspecto unidimensional reduz as negociações à variável preço, produzindo, muitas vezes, resultados aquém do desejado. No caso brasileiro, o Governo Federal instituiu o Portal Comprasnet, através do qual, as organizações públicas adquirem bens e serviços de fornecedores cadastrados. Dentre as modalidades de licitação disponíveis, destaca-se o Pregão Eletrônico, um mecanismo de leilão eletrônico reverso baseado no atributo preço, através do qual, fornecedores submetem lances decrescentes, na disputa por contratos do setor público. No presente trabalho, o autor propõe uma abordagem de decisão multicritério, baseada na Teoria da Utilidade Multiatributo, como uma alternativa para a adoção de leilões reversos baseados em múltiplos atributos e, consequentemente, para uma maior agregação de valor pelas organizações compradoras do setor público brasileiro.
16

Multicriteria Techniques for Sustainable Supply Chain Management

Barrera Jimenez, Ivan Felipe 30 January 2025 (has links)
Tesis por compendio / [ES] Los métodos multicriterio proporcionan un enfoque analítico y estructurado para la toma de decisiones en la gestión de la cadena de suministro, que permiten evaluaciones basadas en múltiples criterios, esenciales para gestionar socios comerciales sostenibles. El objetivo de esta tesis es contribuir a la gestión sostenible de la cadena de suministro desarrollando nuevos modelos y técnicas multicriterio para evaluar proveedores y clientes. Se han diseñado modelos que incorporan las preferencias empresariales para tomar decisiones colaborativas en la selección y clasificación transparente de alternativas basadas en criterios sostenibles. También se han desarrollado métodos para clasificar las alternativas en grupos ordenados y evaluar su calidad. Tanto los modelos como los métodos se han validado mediante casos empíricos y comparado con enfoques alternativos. La metodología se basa en una profunda revisión bibliográfica y en el conocimiento experto de profesionales en la cadena de suministro. Los modelos multicriterio propuestos emplean técnicas como el Analytic Hierarchy Process (AHP), la Multi-Attribute Utility Theory (MAUT) y PROMETHEE. También se han desarrollado tres algoritmos para la clasificación de alternativas (nominal y ordenada). En primer lugar, se ha propuesto un modelo multicriterio híbrido y se ha validado con datos reales para homologar y seleccionar proveedores de tecnología, así como para su priorización y clasificación. Este modelo integra métodos compensatorios (AHP, MAUT) y no compensatorios (PROMETHEE, FlowSort) en una jerarquía con criterios de sostenibilidad. La validación del modelo en un contexto real y su comparación con un modelo alternativo ha demostrado su capacidad para proporcionar información relevante y transparente en la toma de decisiones para la evaluación sostenible de proveedores de tecnología en el sector bancario. En segundo lugar, se ha diseñado un nuevo algoritmo, denominado Global Local Net Flow sorting (GLNF sorting), que clasifica alternativas en grupos ordenados a partir de los flujos netos generados en búsquedas globales y locales con PROMETHEE. Adicionalmente, se ha diseñado el algoritmo SILhouette for Sorting (SILS) para calcular un índice de calidad en las clasificaciones. Ambos algoritmos se han validado empíricamente en la segmentación de proveedores y sus resultados se han comparado con otros métodos publicados. Por una parte, GLNF sorting destaca al mejorar la discriminación entre proveedores cercanos a los perfiles limitantes de los grupos, aprovechando el nivel de similitud preferencial entre alternativas. Por otra, SILS mejora la calidad de las asignaciones y permite un análisis detallado que facilita la toma de decisiones. En tercer lugar, se ha propuesto un sistema de segmentación de clientes B2B basado en transacciones y colaboración, aplicando AHP y GLNF sorting. Validado con 8,157 clientes de una multinacional, se ha evaluado con SILS y estadística descriptiva. Comparado con K-means, el modelo genera clasificaciones más homogéneas y robustas. Esta herramienta permite a las empresas automatizar decisiones y llevar a cabo análisis detallados para mejorar las relaciones con los clientes, alineándose con sus estrategias de colaboración y enfoques de mercado. En cuarto lugar, las búsquedas globales y locales se han utilizado para proponer un algoritmo de clasificación nominal basado dos dimensiones, que proporciona una matriz estratégica muy útil para los gestores de cadena de suministro. Por último, se ha desarrollado el paquete de software PrometheeTools en R, que automatiza la aplicación de PROMETHEE, GLNF sorting y SILS para resolver problemas multicriterio de priorización y clasificación de alternativas. Este paquete se ha validado con éxito y destaca por su eficiencia en PROMETHEE con miles de alternativas. Está disponible en acceso abierto en el repositorio CRAN para su utilización por investigadores y profesionales interesados en toma de decisiones multicriterio. / [CA] Els mètodes multicriteri proporcionen un enfocament analític i estructurat per a la presa de decisions en la gestió de la cadena de subministrament, que permeten avaluacions basades en múltiples criteris, essencials per a gestionar socis comercials sostenibles. L'objectiu d'aquesta tesi és contribuir a la gestió sostenible de la cadena de subministrament desenvolupant nous models i tècniques multicriteri per a avaluar proveïdors i clients. S'han dissenyat models que incorporen les preferències empresarials per a prendre decisions col·laboratives en la selecció i classificació transparent d'alternatives basades en criteris sostenibles. També s'han desenvolupat mètodes per a classificar les alternatives en grups ordenats i avaluar-ne la qualitat. Tant els models com els mètodes s'han validat mitjançant casos empírics i comparat amb enfocaments alternatius. La metodologia es basa en una profunda revisió bibliogràfica i en el coneixement expert de professionals en la cadena de subministrament. Els models multicriteri proposats empren tècniques com ara el procés analític jeràrquic (AHP), la teoria d'utilitat multiatribut (MAUT) i PROMETHEE. També s'han desenvolupat tres algoritmes per a la classificació d'alternatives (nominal i ordenada). En primer lloc, s'ha proposat un model multicriteri híbrid i s'ha validat amb dades reals per a homologar i seleccionar proveïdors de tecnologia, així com per a la seua priorització i classificació. Aquest model integra mètodes compensatoris (AHP, MAUT) i no compensatoris (PROMETHEE, FlowSort) en una jerarquia amb criteris de sostenibilitat. La validació del model en un context real i la seua comparació amb un model alternatiu n'ha demostrat la capacitat per a proporcionar informació rellevant i transparent en la presa de decisions per a l'avaluació sostenible de proveïdors de tecnologia en el sector bancari. En segon lloc, s'ha dissenyat un nou algoritme, denominat Global Local Net Flow sorting (GLNF sorting), que classifica alternatives en grups ordenats a partir dels fluxos nets generats en cerques globals i locals amb PROMETHEE. Addicionalment, s'ha dissenyat l'algoritme SILhouette for Sorting (SILS) per a calcular un índex de qualitat en les classificacions. Ambdós algoritmes s'han validat empíricament en la segmentació de proveïdors i els seus resultats s'han comparat amb altres mètodes publicats. D'una banda, GLNF sorting destaca en millorar la discriminació entre proveïdors pròxims als perfils limitants dels grups, que aprofita el nivell de similitud preferencial entre alternatives. De l'altra, SILS millora la qualitat de les assignacions i permet una anàlisi detallada que facilita la presa de decisions. En tercer lloc, s'ha proposat un sistema de segmentació de clients B2B basat en transaccions i col·laboració, aplicant AHP i GLNF sorting. Validat amb 8,157 clients d'una multinacional, s'ha avaluat amb SILS i estadística descriptiva. Comparat amb K-means, el model genera classificacions més homogènies i robustes. Aquesta eina permet a les empreses automatitzar decisions i portar a cap anàlisis detallades per a millorar les relacions amb els clients, que s'alineen amb les seues estratègies de col·laboració i enfocaments de mercat. En quart lloc, les cerques globals i locals s'han utilitzat per a proposar un algoritme de classificació nominal basat en dues dimensions, que proporciona una matriu estratègica molt útil per als gestors de la cadena de subministrament. Finalment, s'ha desenvolupat el paquet de programari PrometheeTools en R, que automatitza l'aplicació de PROMETHEE, GLNF sorting i SILS per a resoldre problemes multicriteri de priorització i classificació d'alternatives. Aquest paquet s'ha validat amb èxit i destaca per la seua eficiència en PROMETHEE amb milers d'alternatives. Està disponible en accés obert en el repositori CRAN per a la utilització per investigadors i professionals interessats en la presa de decisions multicriteri. / [EN] Multicriteria methods provide an analytical and structured approach to decision making in supply chain management. These techniques allow multicriteria evaluations, which are essential for choosing and managing sustainable business partners. The aim of this thesis is to contribute to sustainable supply chain management by developing new multicriteria models and techniques to assess suppliers and customers. Models have been designed in order to incorporate business preferences to make collaborative decisions in the transparent selection and ranking of alternatives based on sustainable criteria. New methods have also been developed to classify alternatives into ordered groups and to assess their quality. Both models and methods have been validated using empirical cases and compared with alternative approaches. The methodology is based on an in-depth literature review, as well as the expertise of supply chain professionals. The proposed multicriteria models integrate techniques such as the Analytical Hierarchical Process (AHP), Multi-Attribute Utility Theory (MAUT) and the PROMETHEE method. Three new algorithms have also been developed for classifying alternatives into nominal and ordered groups (sorting problem). Firstly, a hybrid multicriteria model has been proposed and validated with real data for technology supplier qualifying, selection and ranking. This model integrates compensatory (AHP, MAUT) and non-compensatory (PROMETHEE, FlowSort) methods in a hierarchy with sustainability criteria to evaluate products, suppliers and manufacturers. Validation of the model in a real context and its comparison with an alternative model has demonstrated its ability to provide relevant and transparent information for decision making in the sustainable evaluation of technology suppliers in the banking sector. Secondly, a new algorithm has been designed, called Global Local Net Flow sorting (GLNF sorting), which classifies alternatives into ordered groups based on the net flows generated in global and local searches with PROMETHEE. In addition, the SILhouette for Sorting (SILS) algorithm has been designed to calculate a quality index in the classifications. Both algorithms have been empirically validated in supplier segmentation and their results compared with other published methods. On the one hand, the GLNF sorting algorithm excels in improving the discrimination between suppliers close to the limiting profiles by exploiting the level of preference similarity between alternatives. On the other, SILS improves the quality of alternative assignments to groups, allows for a detailed analysis of suppliers and facilitates decision making. Thirdly, a customer segmentation model based on transactions and collaboration has been proposed in the Business to Business context, applying AHP and GLNF sorting. Validated with 8,157 customers of a multinational company, it has been assessed by SILS and descriptive statistics. This model generates more homogeneous and robust groups than the K-means cluster method. This tool enables companies to automate decisions and perform detailed analysis to improve customer relationships, aligning with their collaboration strategies and market approaches. Fourthly, global and local searches have been used to propose an algorithm for nominal classification based on two dimensions, which provides a very useful strategic matrix for supply chain managers. Finally, the PrometheeTools software package has been developed in R, which automates the implementation of PROMETHEE, GLNF sorting and SILS to solve multicriteria problems of alternatives ranking and classification. This package has been successfully validated and stands out for the efficiency in PROMETHEE and especially when solving problems with thousands of alternatives. It is available by open access in the CRAN repository for use by researchers and practitioners interested in multicriteria decision making. / Barrera Jimenez, IF. (2024). Multicriteria Techniques for Sustainable Supply Chain Management [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202879 / Compendio

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