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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.
241

Využití teorie fuzzy množin a jejich rozšíření v metodě TOPSIS / The use of the fuzzy set theory and their extensions in the TOPSIS method

Pokorný, Tomáš January 2016 (has links)
This master's thesis deals with extensions of TOPSIS method, which is one of methods for multi-criteria evaluation of alternatives. These extensions use theory of fuzzy sets (FS) and their futher extensions to interval-valued (IVFS), intuitionistic (IFS) and hesitant (HFS) fuzzy sets and their combinations (IVIFS, IVIHFS). Significant part of this thesis explains the principle of fuzzy sets and their generalizations. Descriptions of operators for aggregations of grades of membership has very important role here. Next, very short description of multi-criteria evaluation problems and detailed description of TOPSIS method are contained. The second half of this thesis is dedicated to four existing extensions of TOPSIS metod that uses theories of FS, IVFS, IVIFS and IVIHFS. Every method is illustrated with an example that shows principle of calculations. It illustrates new possibilities of the methods that use new sets theories and potential complications and deviations from the original TOPSIS method. At the end of this thesis, evaluation of usefulness of used approaches is mentioned.
242

New AHP methods for handling uncertainty within the Belief Function Theory / De nouvelles méthodes, fondées sur l'AHP, pour traiter l'incertitude à l'aide de la théorie des fonctions de croyance

Ennaceur, Amel 29 May 2015 (has links)
L'aide à la décision multicritères regroupe des méthodes permettant de choisir la meilleure solution en fonction des différents critères et compte tenu des préférences des experts. Toutefois, ces préférences sont parfois exprimées de manière imparfaite. La théorie des fonctions de croyance modélise de manière souple les connaissances et fournit des outils mathématiques pour gérer les différents types d'imperfection. Ainsi dans cette thèse, nous nous intéressons à la prise de décision multicritères dans un cadre incertain en étendant la méthode d’Analyse Hiérarchique des Procédés (AHP) à la théorie des fonctions de croyance. Après avoir présenté les fondements théoriques de la méthode AHP, nous avons proposé une approche qui permet de réduire le nombre de comparaisons par paires en jugeant des sous-ensembles de critères et d’alternatives. En outre, nous avons examiné la dépendance entre les critères et les alternatives. Dans ce cas, l'incertitude au niveau des évaluations est donnée sous forme de masses conditionnelles. Une autre partie de nos travaux répond aux critiques concernant la procédure de comparaison. Pour cela, nous avons proposé deux approches. La première technique d’élicitation des jugements de l’expert est fondée sur des distributions de masses, alors que la seconde s'appuie sur des relations de préférence. Dans ce cadre, nous avons introduit un modèle qui permet de générer des distributions de masse quantitatives à partir des relations de préférence. Ainsi, nous avons développé une méthode multicritères qui permet d'imiter le raisonnement humain. Cette méthode produit des résultats meilleurs et plus robustes que les approches de la littérature. / Multi-criteria decision making is the study of identifying and choosing alternatives to find the best solution based on different criteria and considering the decision makers’ expectations. However, the expert assessments are sometimes expressed imperfectly. Belief function theory can then provide more flexible and reliable tools to manage different types of imperfection. Thus, in this thesis, we are interested in multi-criteria decision making in an uncertain framework by extending the Analytic Hierarchy Process (AHP) method to the belief function framework. After presenting the theoretical foundations of the AHP method, we proposed an approach that reduces the number of pair-wise comparisons by judging subsets of criteria and alternatives. In addition, we examined the dependence between the criteria and alternatives. In this case, the uncertainty is given in terms of conditional mass distributions. Another part of the work provides critical concerning the pair-wise comparison process. For this purpose, we proposed two approaches. The first expert judgment elicitation method is based on mass distributions, while the second one is based on preference relations. In this context, we have introduced a model that is able to generate quantitative mass distributions from preference relations. Thus, we have developed a multi-criteria decision making method that imitates human reasoning. This method gives better and more robust results than existing approaches.
243

Evaluation participative de scénarios : quelles perspectives pour les systèmes agricoles camarguais ? / Participatory assessment of scenarios : perspectives for agricultural systems in Camargue, South of France

Delmotte, Sylvestre 19 December 2011 (has links)
Les systèmes agricoles sont en constante évolution sous les effets conjugués d'innovations techniques et organisationnelles et de changements du contexte socio-économique. A l'échelle d'un territoire, des acteurs locaux peuvent encourager et accompagner des changements de ce type s'ils ont une vision claire de leurs impacts potentiels. L'objectif de cette thèse est d'élaborer et d'appliquer une démarche permettant d'assister agriculteurs et autres acteurs locaux d'un territoire dans la construction et l'évaluation de scénarios d'évolutions des systèmes agricoles. Une démarche basée sur des approches permettant une analyse prospective, multicritères, multi-échelles et participative d'évaluation des systèmes agricoles a été développée. Elle a été mise en œuvre en Camargue (sud-est de la France), avec des exploitants céréaliers et des acteurs de la production agricole et de la gestion du territoire.Des scénarios portant sur la réforme de la politique agricole commune (PAC) en 2012-2014, ainsi que sur des objectifs nationaux de réduction de la consommation de pesticides et de développement de l'agriculture biologique ont été développés. Ces perspectives d'évolution des systèmes agricoles camarguais ont été évaluées, via la formalisation de nombreuses données et connaissances. Deux outils de modélisation ont été utilisés : un modèle multi-agent a permis la mise en place de séances de simulation interactives avec des agriculteurs, et un modèle bioéconomique a été développé et utilisé avec des acteurs locaux tels que le syndicat des riziculteurs et le parc naturel régional.Les scénarios portant sur la réforme de la PAC ont confirmé la dépendance des exploitations rizicoles aux subventions. Des agriculteurs ont testé différentes stratégies d'adaptation de leurs exploitations à la suppression de l'aide couplée à la production rizicole. Ces stratégies, souvent basées sur la diversification des activités ou sur la conversion à l'agriculture biologique, ne permettaient pas de compenser les pertes économiques liées à la disparition de l'aide couplée. A l'échelle du territoire, ces stratégies réduiraient fortement la surface cultivée en riz, avec des impacts importants sur d'autres activités en lien avec la production agricole. Cependant ces stratégies vont dans le sens des objectifs gouvernementaux de réduction des impacts de l'agriculture sur l'environnement. Des scénarios portant spécifiquement sur ces objectifs ont permis d'identifier des marges de manœuvre importantes au niveau des exploitations céréalières camarguaises.Cette thèse propose un cadre pour la mise en œuvre de démarches d'évaluation des systèmes agricoles dans un territoire, qui associe les agriculteurs et les acteurs locaux à différentes étapes, depuis leur engagement pour le choix des scénarios, l'acquisition et l'analyse des données, la construction des outils de simulation et l'évaluation de scénarios. La combinaison de différents outils de modélisation pour la réalisation de réflexions collectives, pourrait contribuer à la mise en place d'actions pour un développement durable de l'agriculture / Agricultural systems are constantly evolving driven by technical and organizational innovations and changes in their socio-economical context. At regional scale local stakeholders can encourage and accompany foreseen changes if they can have clear visions of their potential impacts. The objective of the PhD thesis was to develop and test a framework to assist farmers and local stakeholders of a region in the building and assessment of scenarios related to agricultural systems. This framework is based on different modeling approaches for a participative, integrated, multi-scale and prospective assessment of agricultural systems. It was implemented in the Camargue region, South-East of France, with cereal farmers and local stakeholders involved in agricultural production and territorial management.Scenarios assessed were related to the reform of the common agricultural policy (CAP) of the European Union in 2012-2014, and to national objectives of reduction in pesticide use and extension of organic farming (OF). Several data and expert knowledge have been formalized and used in these simulations of scenarios. Two modeling tools have been used for scenario assessment with stakeholders: an agent-based model allowed interactive simulation sessions with farmers, and a bio-economic model was co-developed and used with local stakeholders such as the French Union of Rice Producer and Industry and the Regional Natural Park, both important stakeholders influencing local agricultural systems. Assessing scenarios related to the CAP reform showed the strong dependency of rice farms to EU subsidies. Farmers involved in the sessions tested several adaptation strategies for their farms in response to the disappearance of the rice coupled payment. These strategies often implied a diversification of production and/or the conversion to OF, but they did not allowed to compensate the economic loss due to the suppression of the rice coupled payment. At the regional level, these strategies would lead to an important decrease on the area cultivated with rice, and therefore have an impact on other related activities in the region. Diversification of production is also a key strategy in scenarios related to governmental objectives of reducing pesticide use and conversion to OF. Therefore, in Camargue, there is room for maneuver for conciliating environmental and economic objectives related to agricultural production.This thesis proposed and applied a framework for participatory integrated assessment of agricultural systems. This framework associates closely farmers and other stakeholders in all phases of scenario assessment (scenario definition, data gathering and analysis, the building and use of models). The way different modeling tools are used in this framework could contribute for collective assessment of future farming systems and support collective actions for sustainable agricultural development.
244

Análise de decisão multicritério de cenários alternativos para o sequenciamento de tarefas em computadores em datacenter / Analysis multicriteria decision of alternative scenarios for the task sequencing on computers in datacenter

Rodrigues Junior, José Luiz 17 June 2015 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2016-06-01T14:36:20Z No. of bitstreams: 1 Jose Luiz Rodrigues Junior.pdf: 1816384 bytes, checksum: f83b0cfa9558fadd55f06d3f851584a9 (MD5) / Made available in DSpace on 2016-06-01T14:36:20Z (GMT). No. of bitstreams: 1 Jose Luiz Rodrigues Junior.pdf: 1816384 bytes, checksum: f83b0cfa9558fadd55f06d3f851584a9 (MD5) Previous issue date: 2015-06-17 / In current data centers, processing routines are scheduled to perform in a given period of time and, in case of delay, make it impossible to conduct the activities of everyday life of the various sectors of the company. Even with modern servers, due to the large volume of data to be processed, it is possible that certain computers are overloaded causing a drop in performance, a longer time to implement and consequently delays in the delivery of results. In this case, alternative scenarios can be created to sequence the tasks again. This work aimed to apply the multi-criteria decision analysis method on the results of the simulation of alternative scenarios for sequencing tasks on computers in a datacenter, in order to overload the resolution of problems. To achieve this purpose have been developed simulation models of task sequencing scenarios and replacement of computer overloaded. The analysis of simulation results was made based on three criteria, namely the Total Processing Time (makespan), the Total delay time, and the number of Delayed Tasks. Subsequently, the results were submitted to analysis method of AHP multicriteria decision (Analitycal Hierarchy Process), allowing you to choose the best setting according to established criteria. It was concluded that the modeling and computer simulation, combined with multi-criteria decision analysis method, can aid in decision making, as it enables sequencing to identify the best solution possible alternative scenarios in front of a computer overload situations. / Nos atuais Datacenters, as rotinas de processamento são programadas para executar em determinado período de tempo e, em caso de atraso, impossibilitar a condução das atividades do dia a dia dos diversos setores da empresa. Mesmo com os modernos servidores, devido ao grande volume de dados para serem processados, é possível que determinados computadores sejam sobrecarregados provocando uma queda em seu desempenho, um tempo maior para a execução e, consequentemente, atrasos na entrega dos resultados. Nesse caso, cenários alternativos podem ser criados para sequenciar novamente as tarefas. Assim, este trabalho teve por objetivo aplicar o método de análise de decisão multicritério nos resultados da simulação de cenários alternativos para o sequenciamento de tarefas em computadores de um Datacenter, visando a resolução para problemas de sobrecarga. Para atingir esse propósito, foram desenvolvidos modelos de simulação de cenários de sequenciamento de tarefas e substituição do computador com sobrecarga. A análise dos resultados da simulação foi realizada considerando três critérios, a saber: o Tempo Total de Processamento (makespan), o Tempo Total de Atraso, e o Número de Tarefas Atrasadas. Posteriormente, os resultados foram submetidos ao método de análise de decisão multicritério AHP (Analitycal Hierarchy Process), permitindo escolher o melhor cenário segundo os critérios estabelecidos. Concluiu-se que a modelagem e simulação computacional, aliada ao método de análise de decisão multicritério, pode auxiliar na tomada de decisão, uma vez que possibilita identificar a melhor solução de sequenciamento em cenários alternativos possíveis diante de situações de sobrecarga de um computador.
245

Developing a holistic framework to investigate the environmental, social, and economic suitability of tidal stream energy in British Columbia’s remote coastal diesel reliant First Nations Communities

Richardson, Riley L. 06 January 2021 (has links)
This thesis holistically examines the potential for tidal stream turbine (TST) integration to displace diesel generated electricity in remote coastal First Nations communities within the Marine Plan Partnership for the North Pacific Coast region of British Columbia. This thesis utilizes a combination of spatial analysis (GIS Multi-Criteria Decision Analysis) to identify sites; stakeholder engagement to assess TST suitability, bridge knowledge gaps, and understand desired characteristics of community energy systems; and Levelized Cost of Energy (LCOE) analyses for existing diesel and externality included scenarios along with potential TST costs in a candidate community. Results illustrate the need for information within these communities, from resource quantification to characteristics of renewable energy technologies and system feasibility; self-sufficiency as being the primary transition driver; and funding/human resource capacity as being substantial barriers. Within the study region ≈89.8 km2 of feasible resource was identified, with ≈22 km2 of potentially suitable tidal resource in proximity to nine communities. The COVID-19 pandemic resulted in difficulties contacting and arranging interviews with the most suitable communities. Driven by the holistic research mandate requiring community stakeholder engagement to occur in tandem with the economic analyses, Queen Charlotte Village and Skidegate Landing on Haida Gwaii were chosen as the candidate communities, despite not being the most suitable identified communities. The community interviews revealed TSTs as being an acceptable renewable energy technology. Furthermore, the identified site in Skidegate Inlet (SI) was found to have favourable Marine Spatial Planning (MSP) for TST development. Existing diesel generation carries a LCOE of $0.63/kWh, being $0.08-0.14 more per kWh than the literature cited LCOE range for TSTs. The LCOE for CO2 equivalent externalities at current carbon tax prices was found to be an additional $0.02/kWh. Despite having a technically viable peak spring current speed, the SI site was financially unviable for 284 kW of rated capacity across all diesel LCOE scenarios driven by capacity factor (1.62%), high cabling costs (approximately one third of capital costs), and outdated data/assumptions within the Natural Resources Canada Tidal Project Cost Estimation tool used in the tidal LCOE calculations. This work contributes to the progression of tidal energy development on BCs coast along with demonstrating the utility of holistic assessment frameworks for RETs across environmental, social, and economic considerations. The results of this thesis can inform existing MSP efforts in the Marine Plan Partnership for the North Pacific region and the framework developed can be built upon and altered for global use in pursuit of sustainable energy transitions. / Graduate
246

Metodika využití technologie GIS v realitním inženýrství / Methodology using GIS technology in real estate engineering

Viktorová, Stanislava Unknown Date (has links)
The doctoral thesis deals with the interdisciplinary issue of variants evaluation from real estate engineering, multi-criteria analyses and geographic information systems, and represents the technological ways of the visual aspect related to mutual spatial relations of real estates. The thesis describes the design and verification of methodology dealing with the use of GIS technology in real estate engineering. The primary element of the methodology is the locality as a fundamental determinant of the real estate market objects to which strictly applies a unique characteristic of spatial information. The object location as such is defined by a large number of criteria that need to be spatially analysed. For the needs of spatial analysis was chosen combination of GIS technology with multi-criteria methods (MCDA) which evaluate variants of the problem. Objective determination of a suitable combination of weighting methods and multi-criteria methods is part of the methodology. An objective determination should lead to a reduction in the human factor risk by determining preferences and variants. The proposed procedures are validated on case studies which were dealt with in specific projects. This methodology should be beneficial not only for the criteria evaluation of price comparison in real estate engineering but also for several areas of multi-criteria decision making in terms of space and location-related data.
247

Optimalizace konstrukce zvedače dutinky spřádacího stroje / Optimalization construction tube lifter of spinner machine

Jeník, Jan January 2012 (has links)
The first part of this thesis describes the current technologies of mechanical spin-ning. This is a ring, rotor and air-jet spinning. The product of spinning machines is yarn, the basic material for production textile. The next section describes in detail the current state of the node manipulator lifter tube on spinning machine TORNADO J20, by concern RIETER. It describes the structure, kinematics, duty cycle and requirements for the manipulator. The following optimization options which are described more options for solutions of individual functions of the manipulator, on the end is selected by multi-criteria analysis. The best solution that is elaborate in the next section. The author has created 3-D model optimized lifter tube. Positioning mechanism maintains the current kinematics, it is very similar. But gripper was designed as a passive, thus reduce the load positioning mechanism. Optimization was performed primarily to reduce overall production costs and to reduce weight manipulator. The conclusion is a comparison of current and new solutions. There are also eco-nomic recovery to.
248

Návrh a posouzení uspořádání nové lakovací linky ve společnosti Automotive Lighting / Design and assessment of a new paint line arrangement at Automotive Lighting

Bouček, Filip January 2013 (has links)
The thesis deals with the design and arrangement of a new paint line at company Automotive Ligting s.r.o in Jihlava. It deals with design of several possible options of arrangement of machines that are required for the processing of polycarbonate granules and their conversion into acrylic glass using two-component injection molding. The glass is then coated with the coating line which is part of the arrangement included in this project. Design of the individual sites and their organization is based on both the company's requirements and the principles of technological design. The best of the three options is analyzed in detail and evaluated from the economic point of view.
249

Studie obchvatu Valašského Meziříčí / The study bypass Valasske Mezirici

Horka, Pavel January 2017 (has links)
The subject of the thesis is to elaborate the search study of the west four-line bypass of the town of Valašské Meziříčí. The reasons for constructing the bypass are to divert heavy transit traffic, to increase safety in the town and to reduce the negative impacts of transport. Road is designed as a category R21,5/100. Three Seven direction solutions were designed of which one was chosen by multi-criteria analysis for further solution.
250

Creation of a Biodiversity Severity Index to evaluate the risks of accidental pollutions in the industry : a multi-criteria sorting approach / Création d'un indice de gravité sur la biodiversité pour évaluer les risques de pollutions accidentelles dans l'industrie : une approche de tri multi-critères

Denat, Tom 05 July 2017 (has links)
Cette thèse s'appuie sur deux axes. L'un appliqué traite de la création d'un indicateur dont le but est d'évaluer la gravité attendue des conséquences d'un scénario de pollution accidentelle. J'ai choisi d'utiliser des outils méthodologiques appartenant au domaine de l'aide multi-critères à la décision pour traiter ce premier sujet. Ce problème impliquant plusieurs disciplines scientifiques, j'ai choisi de le diviser en plusieurs sous-problèmes à travers une arborescence de critères. J'ai également impliqué plusieurs experts, notamment en toxicologie et en écologie afin de mieux prendre en compte les aspects liés à ces deux disciplines dans la création de cet indicateur.L'étude des méthodes de tri multicritère effectuée lors des recherches sur le premier axe m'a amené à en proposer une nouvelle que j'ai nommé algorithme du Dominance Based Monte Carlo (DBMC). Cet algorithme a comme particularités de n'être pas fondé sur un modèle et de fonctionner de manière stochastique. Nous avons étudié ses propriétés théoriques, en particulier nous avons démontré qu'en dépit de sa nature stochastique, le résultat de l'algorithme Dominance Based Monte Carlo converge presque sûrement. Nous avons également étudié son comportement et ses performances pratiques à travers un test nommé k-fold cross validation et les avons comparés aux performances d'autres algorithmes d'élicitation des préférences pour le tri multi-critères. / This thesis is based on two main axes. The first one deals with the creation of an indicator that aims at evaluating the expected severity of the consequences of a scenario of accidental pollution. In order to create this methodology ofevaluation, I chose to use methodological tools from multi-criteria decision aiding. So as to deal with the complexity of this problem, i decided to split it into several sub-problems using a hierarchy of criteria, being mainly inspired by the "value focused thinking approach". In this work, I interacted with several experts in toxicology and in ecology in order to betterdeal with every aspect of this problem.While studying several elicitation methods for the multi-criteria sorting problem, I proposed a new one that I named Dominance Based Monte Carlo algorithm (DBMC), which brings me to the secons axis of this thesis. This elicitation algorithm has two main specificities: being model free and a stochastic functionning. In this thesis, we study its theoretical properties. In particular, we prove that despite its stochastic nature, the result of the Dominance Based Monte Carlo algorithm converges almost surely. We also study its practical performances through a test named k-fold validation and we compared these performances to those of other elicitation algorithms for the sorting problem.

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