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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.
1

A Multicriteria Perspective on Reverse Auctions

De Smet, Yves 20 December 2005 (has links)
Investigate the use of partial relations for multicriteria reverse auctions. At first, a theoretical framework is introduced. Then, an extension of traditional multicriteria tools is considered. This is referred to as the Butterfly model. Finally, the concept of Bidding Niches partitions is formalized and tested.
2

Provision of intelligent user support in decision support systems

Hodgkin, Julie January 2001 (has links)
No description available.
3

Multiattribute models for engineering evaluation

Jessop, Alan Thomas January 1999 (has links)
No description available.
4

Modelling conflict of objectives in responding to some of the changes in the common agricultural policy : the case of irrigated agriculture in Andalusia, Spain

Arriaza, Manuel January 2000 (has links)
No description available.
5

Vícekriteriální rozhodování o investicích do reklamy v ČR / Mutlicriteria decision making about investments in advertising in Czech Republic

Šícha, Jaroslav January 2008 (has links)
The goal of this disertation work is to find a mathematical model, which could help marketing workers to decide in which media to invest money for advertising. It includes decription of each media channel (TV, radio, press and internet), the mathematical model and it's computation based on two methods and a real-life example.
6

Self Designing Pattern Recognition System Employing Multistage Classification

Abdelwahab, Manal M. 01 January 2004 (has links)
Recently, pattern recognition/classification has received a considerable attention in diverse engineering fields such as biomedical imaging, speaker identification, fingerprint recognition, etc. In most of these applications, it is desirable to maintain the classification accuracy in the presence of corrupted and/or incomplete data. The quality of a given classification technique is measured by the computational complexity, execution time of algorithms, and the number of patterns that can be classified correctly despite any distortion. Some classification techniques that are introduced in the literature are described in Chapter one. In this dissertation, a pattern recognition approach that can be designed to have evolutionary learning by developing the features and selecting the criteria that are best suited for the recognition problem under consideration is proposed. Chapter two presents some of the features used in developing the set of criteria employed by the system to recognize different types of signals. It also presents some of the preprocessing techniques used by the system. The system operates in two modes, namely, the learning (training) mode, and the running mode. In the learning mode, the original and preprocessed signals are projected into different transform domains. The technique automatically tests many criteria over the range of parameters for each criterion. A large number of criteria are developed from the features extracted from these domains. The optimum set of criteria, satisfying specific conditions, is selected. This set of criteria is employed by the system to recognize the original or noisy signals in the running mode. The modes of operation and the classification structures employed by the system are described in details in Chapter three. The proposed pattern recognition system is capable of recognizing an enormously large number of patterns by virtue of the fact that it analyzes the signal in different domains and explores the distinguishing characteristics in each of these domains. In other words, this approach uses available information and extracts more characteristics from the signals, for classification purposes, by projecting the signal in different domains. Some experimental results are given in Chapter four showing the effect of using mathematical transforms in conjunction with preprocessing techniques on the classification accuracy. A comparison between some of the classification approaches, in terms of classification rate in case of distortion, is also given. A sample of experimental implementations is presented in chapter 5 and chapter 6 to illustrate the performance of the proposed pattern recognition system. Preliminary results given confirm the superior performance of the proposed technique relative to the single transform neural network and multi-input neural network approaches for image classification in the presence of additive noise.
7

Etude de l'effet du conflit multicritère sur l'expression des préférenes : Une approche empirique / The Effect of the Multicriteria Conflict on the Expression of Preferences : an Empirical Approach

Deparis, Stéphane 15 June 2012 (has links)
Le travail de recherche présenté dans cette thèse s'inscrit dans le champ de l'aide multicritère à la décision. Ce champ concerne la décision dans un contexte où les alternatives sont jugées sous divers aspects, souvent conflictuels. Notre travail s'insère dans une approche descriptive et cherche à observer l'effet du conflit multicritère sur les préférences exprimées par le décideur. Dans un premier temps, nous proposons une définition de l'intensité du conflit multicritère entre deux alternatives puis nous nous intéressons aux préférences incomplètes et identifions deux classes de modèles de préférences incomplètes. Notre principale contribution est ensuite d'observer et analyser l'effet du conflit lors du recueil des préférences d'un décideur. Nous avons pour cela conçu et mené deux expérimentations permettant de tester le recueil de préférences à travers des comparaisons par paires, et à travers des matchings. La première expérimentation nous permet de mettre en évidence une forme d'intransitivité de l'indifférence le long des chaînes d'isopréférence. Un fort conflit multicritère conduit les sujets à exprimer des préférences incomplètes. Les résultats obtenus lors de cette expérimentation sont en cours de publication (Deparis et al. [2012]). La seconde expérimentation nous permet de montrer que les asymétries déjà observées dans la littérature en réponse à un bi-matching sont fortement amplifiées par l'effet du conflit multicritère. Nous discutons des implications de ces résultats en termes d'élicitation des préférences. Enfin, nous analysons les résultats expérimentaux au regard de la labilité des préférences qu'ils révèlent. Au-delà de cette contribution, notre thèse permet de mieux comprendre les interactions qui peuvent exister entre les approches normative, descriptive et prescriptive en décision multicritère. / The research presented in this thesis lies in the field of multicriteria decision aid. This field deals with decision in a context where several aspects, usually in conflict, are considered when judging the alternatives. Our work stands in the descriptive approach and aims at observing the effect of multicriteria conflict on the preferences expressed by decision-makers. First, we propose a definition of the intensity of inter-alternative multicriteria conflict and then we consider incomplete preferences and identify two types of incomplete preference models. Our main contribution is then to observe and analyse the effect of conflict when assessing the preferences of a decision-maker. In order to do so, we designed and led two experiments allowing to test the assessment of preferences through pairwise comparisons and matchings. The first experiment allows us to exhibit an intransitivity of indifference along isopreference chains. A large multicriteria conflict leads subjects to express incomplete preferences. Results obtained from this experiment are under publication (Deparis et al. [2012]). The second experiment allows us to show that asymmetries already observed in the literature in response to bimatchings are strongly amplified by multicriteria conflict. We discuss the implications of these results on elicitation of preferences. Finally, we analyse the experimental results with regard to the lability of preferences that they reveal. Beyond this contribution, our thesis sheds a light on the interactions that exist between the normative, descriptive and prescriptive approaches in multicriteria decision-making.
8

Metod för bedömning och jämförelse av insamlings- och sorteringssystem för hushållsavfall : Utveckling av ett verktyg för multikriterieanalys med en- och fåfamiljshus i Linköpings kommun som fall / Method for assessment and comparison of household waste collection and sorting systems : Development of a multi-criteria analysis tool using small houses in Linkoping municipality as case

Dannert, Sofia, Norström, Josefin January 2018 (has links)
En av de största globala utmaningarna idag är de negativa miljöeffekterna från den linjära ekonomin som världen bygger på, där produkter oupphörligt skapas från jungfruliga råvaror och efter användningstiden slutar som avfall utan nytta. Initiativ på flera nivåer; lokalt, regionalt, nationellt och globalt, krävs för att uppnå en cirkulär ekonomi där uppkomsten av avfall, samt utvinningen av jungfruliga råvaror, minskar. Europeiska unionens handlingsplan för cirkulär ekonomi säger att 75 % av alla förpackningar ska materialåtervinnas till år 2030. I Sverige materialåtervinns mellan 42,2 % (plastförpackningar) och 95 % (glas) och fastighetsnära insamlingssystem för förpackningar och tidningar är förhållandevis väl utbyggda, åtminstone för flerfamiljshus. Gällande småhus har utvecklingen gått något långsammare även om flera kommuner idag infört fastighetsnära insamling för hushållsavfall, inklusive förpacknings- och tidningsavfall. Att välja ett nytt, utökat avfallssystem till en kommun är ett stort och komplext beslut med många aspekter att ta hänsyn till. Flera tidigare utredningar inför denna typ av beslut har saknat en tydlig målbild, metodik och systematik i granskningen, varför syftet med denna studie varit att utveckla en metod för att genomföra en systematisk multikriterieanalys av ett antal avfallssystem för insamling och sortering av hushållsavfall från småhus i en kommun.  Innan multikriterieanalysen påbörjades gjordes en omfattande kartläggning av de aspekter som är kopplade till beslutet om ett nytt avfallssystem. Kartläggningen och det urval av aspekter som gjordes till multikriterieanalysen är värdefull kunskap för kommuner som står inför denna typ av beslut. Multikriterieanalysen har tagits fram med inspiration från den generiska formen av en multikriterieanalys där Linköpings kommun och Tekniska verken använts som fall. På grund av detta har även de system som utvärderats valts ut med hänsyn till intressanta avfallssystem för Linköpings kommun. Den framtagna multikriterieanalysen har paketerats i ett användarvänligt verktyg som kan användas av beslutsfattare i kommuner som önskar att utvärdera och jämföra avfallssystem för småhus.  Studien har resulterat i att det i huvudsak är följande sju kriterier som bör beaktas i en utredning gällande ett nytt insamlings- och sorteringssystem för småhus i en kommun, där resurseffektivitet är av hög prioritet i beslutet:  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="1" data-aria-level="1">Etablerbarhet &amp; flexibilitet  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="2" data-aria-level="1">Miljöpåverkan från materielbehov  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="3" data-aria-level="1">Kundperspektiv  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="4" data-aria-level="1">Arbetsmiljö  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="5" data-aria-level="1">Miljöpåverkan från energianvändning vid drift  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="1" data-aria-level="1">Insamlingsresultat  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="2" data-aria-level="1">Ekonomi  Dessa kriterier har brutits ned i mindre beståndsdelar, kallade indikatorer. När avfallssystem ska utvärderas och jämföras är det essentiellt att de bedöms inom dessa kriterier och indikatorer för att skapa bra underlag inför valet av system.   Studien har kunnat belysa att det i nuläget finns en hel del osäkerheter inom områdena Etablerbarhet &amp; flexibilitet samt Miljöpåverkan från energianvändning i drift som försvårar bedömning av system inom kriterierna. Även vissa avfallssystem saknas tillräcklig kunskap om som krävs för att kunna göra en rättvis bedömning av systemen, mycket till följd av att de är oetablerade i Sverige. / One of the greatest challenges the world is facing today is the negative environmental effects as a result from the linear economy used in societies, where products are constantly being produced from raw materials and end up as waste after the period of usage. Initiatives on many levels; local, regional, national and global are needed to create a circular economy which minimizes both the generation of waste and the extraction of raw materials. The European Union’s action plan for circular economy expresses that 75 % of all packaging waste should be recycled by 2030. In Sweden packaging waste is being recycled between 42,2 % (plastic waste) to 95 % (glass waste) and the curbside collection systems for packaging waste are quite well-developed, especially regarding waste systems for multi-family houses. For single-family houses the development has been slower, although several municipalities have introduced curbside collection systems for household waste including packaging and newspaper waste during the last years. It is a comprehensive and complex decision to invest in a new extended curbside collection and sorting system in a municipality and there are many aspects to consider. Since several previous inquiries regarding this type of decision lacks a systematic approach and clear objectives, the purpose of this study is to develop a method for conducting a systematic multi-criteria analysis of collection and sorting systems for single-family household waste in a municipality.  Prior to the multi-criteria analysis a substantial evaluation of aspects related to the decision of a new waste system was made. The mapping and selection of aspects that were made provide great knowledge for municipalities facing this kind of decision. The developed multi-criteria analysis is based on the generic form of a multi-criteria analysis, using the municipality of Linköping and Tekniska verken as case. As a result, the range of waste systems evaluated have been selected according to the preferences of Linköping municipality. The developed multi-criteria analysis has been transferred to a user-friendly tool for decision makers at municipalities who wish to assess and compare extended collection and sorting systems for single-family household waste.  The study has resulted in the following criteria which should be considered in an inquiry of waste systems for single-family houses in a municipality, where resource efficiency is highly prioritized:  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="1" data-aria-level="1">Establishment &amp; flexibility  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="2" data-aria-level="1">Environmental impact from usage of materiel  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="3" data-aria-level="1">Customer perspective  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="1" data-aria-level="1">Working standards  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="2" data-aria-level="1">Environmental impact from energy usage during operation  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="3" data-aria-level="1">Collection results  <li data-leveltext="" data-font="Symbol" data-listid="29" data-aria-posinset="4" data-aria-level="1">Economy  These criteria have been divided into smaller components, called indicators. When assessing and comparing waste systems, it is essential to evaluate systems within these criteria and indicators to ensure a thorough basis for this type of decision.  The study has been able to highlight some lack of knowledge within the criteria Establishment &amp; flexibility and Environmental impact from energy usage during operation, which complicates the assessment of waste systems within these areas. Sufficient knowledge regarding some waste systems are also missing, most likely due to the systems not being used in Sweden.
9

A value-centric decision making framework for maintenance services outsourcing

Toossi, Amir January 2011 (has links)
The shift in mindset of decision makers, from maintenance being a “necessary evil” and “cost centre” to a “profit contributor” in manufacturing companies has driven outsourced maintenance suppliers to employ value-centric approaches in order to design more effective maintenance programs. A value assessment for maintenance outsourcing must facilitate the trade-off between cost-centric and value-centric approaches to enable the maintenance service providers to design more effective maintenance organizations. This assessment should also help the customers in a well informed decision making in outsourcing their maintenance function in order to add value to their businesses. Therefore the aim of this research is to develop a decision making framework for maintenance outsourcing based on the assessed customer-value of outsourced maintenance services. Cont/d.
10

Observation et modélisation spatiale de la température dans les terroirs viticoles du Val de Loire dans le contexte du changement climatique / Observation and spatial modeling of temperature in the viticultural terroirs of the Loire Valley in the context od Climate change

Bonnefoy, Cyril 12 April 2013 (has links)
Dans un contexte de changement climatique, les impacts attendus sur les terroirs viticoles posent un certain nombre de questions, notamment sur les risques encourus (variation des caractéristiques et de la qualité du vin) et les enjeux. Ce travail de thèse vise à mettre en place une méthodologie de mesures et de modélisation spatiale de la température, dans les terroirs viticoles du Val de Loire, afin de définir le climat actuel et d’apporter des réponses aux conséquences futures du changement climatique à l’aide de simulations adaptées. Une étude diagnostic des données de températures régionales a préalablement été effectuée et montre une augmentation généralisée de la température et des indices bioclimatiques de la vigne depuis 1950. Des expérimentations à échelles locales ont été réalisées dans les terroirs viticoles de la moyenne vallée de la Loire grâce à un important dispositif de mesures climatiques. La variabilité spatiale de la température est notamment mise en évidence par l’étude d’indices bioclimatiques comme les degrés-jours qui montrent des différences parfois comparables à celles observées à l’échelle régionale. Une modélisation multicritères a été appliquée sur un site expérimental des Coteaux du Layon et montre l’importance des facteurs topographiques dans la variabilité de la température. Une dernière étape a permis d’obtenir des simulations du modèle méso-échelle RAMS. Les simulations à 5 km de résolution sur la période de référence 1991-2000 ont été contrôlées sur certains mois clés de la croissance de la vigne puis confrontées aux sorties du modèle ARPEGE-Climat (50 km). Les résultats montrent l’intérêt de la désagrégation d’échelle par le modèle RAMS avec des biais réduits sur les températures, et notamment une meilleure appréhension des extrêmes thermiques. Les simulations de la période future 2041-2050 (Scénario A2) montrent un recul de l’aléa gélif pour le mois d’avril mais une augmentation de la fréquence des journées chaudes (>30°) et très chaudes (>35°C) pendant la période véraison-maturation. Enfin, les simulations de quelques épisodes extrêmes à 200 mètres de résolution ont soulevé toute la complexité de ce type de modélisation, avec des températures plus ou moins bien reproduites selon les journées. / In the context of Climate Change, the potential impacts for viticultural terroirs pose a number of questions, especially the likely risks (variability in wine characteristics and quality) and implied challenges. This thesis aims to develop a methodology for measuring and modeling the spatial variability in temperature in viticultural terroirs of the Loire Valley, in order to define the current climate and to provide some answers about the future consequences of Climate Change. The temperature trends in the Loire Valley have therefore been analysed since the middle of the 20th century, using the regional weather stations network. The results indicate an increase of temperatures and bioclimatic indices for all the regional stations. Experimentations at local scales have been realized in the viticultural terroirs of the middle-Loire Valley thanks to an important network of weather stations and data loggers. Bioclimatic indices, as the growing-degree days, underline the spatial variability in temperature and show that this variability can sometimes be as significant at fine scale as at larger scales. A multicriteria modeling has been applied on an experimental site in the Coteaux du Layon vineyards and highlights which local factors prevail in the temperature variability. Climatic modeling has been carried out at fine scales in the last stage of this study with the Regional Atmospheric Modeling System (RAMS). Downscaled simulations delivered at high resolution (5 km resolution) for the control period (1991-2000) were compared with ARPEGE-Climat simulations (50 km) for a few important months during vine growth. Results showed that RAMS contributed to reducing the large-scale induced bias and gave better simulations of extremes temperatures. The RAMS assimilation of the SRES A2 scenario for the 2041-2050 period projected frost risk to decrease in April but an increase in the frequency of hot days (>30°C) and very hot days (>35°C) during veraison and berry ripening. Finally, extreme weather simulations revealed all the complexity of this kind of modeling, with contrasted results according to the different simulated days

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