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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

Traitement des congestions dans les réseaux de transport et dans un environnement dérégulé

Manzo, Vincent 22 October 2004 (has links) (PDF)
La restructuration du secteur de l'électricité occasionne des transferts de puissance importants guidés par une logique essentiellement économique,engendrant à leur tour de nouvelles contraintes sur les réseaux de transport appelées congestions. Une congestion dénote l'incapacité du réseau de transport à conduire les programmes du marché de l'énergie, et le traitement des congestions est le procédé assurant que les réseaux sont exploités dans leurs limites de sécurité imposées. Le contexte actuel nécessite donc de définir une méthodologie de traitement des congestions fiable, optimale du point de vue économique, et qui donne de bonnes incitations sur le long terme en vue de réduire les contraintes et de favoriser le développement du réseau. A cet effet, nous proposons dans le cadre de cette Thèse un modèle de traitement des congestions qui définit celui-ci comme un service système séparé du marché de l'énergie. Le traitement repose sur l'usage d'offres d'ajustements venant des producteurs sur une base volontaire, et dont le coût total est minimisé via un algorithme d'optimisation. Ensuite, ce coût est redistribué aux usagers du réseau suivant de nouvelles stratégies d'allocation basées sur la traçabilité de l'énergie. Enfin, cette méthodologie a été adaptée en vue de répondre au problème de la coordination supranationale du traitement des congestions. Les résultats ont montré que cette coordination facilite le traitement de contraintes difficiles, et permet d'espérer des réductions appréciables de coût de congestion, tout en assurant la confidentialité de données économiques sensibles. Les essais ont notamment été effectués sur le réseau RTS 96 comportant 72 nœuds.
2

Intégration dans le réseau électrique et le marché de l'électricité de production décentralisée d'origine renouvelable : gestion des congestions locales

Vergnol, Arnaud 29 November 2010 (has links) (PDF)
Le développement de la production éolienne permet de satisfaire les objectifs de lutte contre le réchauffement climatique. Cependant, dans certaines zones du réseau électrique, l'intégration d'un volume important de production peut créer des congestions qui traduisent l'incapacité du réseau à évacuer cette production. Les méthodes actuelles pour gérer les congestions sont basées sur des calculs prévisionnels de restrictions de production qui peuvent entrainer des pertes de production importantes pour le renouvelable. Cependant, dans le cadre d'un développement important du renouvelable, il est nécessaire de définir une méthodologie de gestion des congestions fiable, optimale du point de vue économique et non discriminatoire pour la production renouvelable.Dans le cadre de cette thèse, la méthodologie de gestion des congestions locales proposée repose sur l'usage d'un contrôle correctif. Le contrôle correctif est basé sur une boucle de régulation et un algorithme utilisant les réseaux de Petri. Une étude de stabilité de la boucle de régulation a montré que les marges de stabilité dépendantes des gains composant la boucle sont suffisantes. L'algorithme permet de définir les groupes de production à choisir pour la gestion des congestions en considérant leur coût d'utilisation et leur impact sur la congestion. Les essais, effectués sous le logiciel EUROSTAG, ont montré la pertinence de la méthodologie proposée et sa capacité à s'adapter à l'insertion des moyens de production. De plus, des conclusions générales sur les différents coûts associés à la gestion des congestions en fonction des différentes règlementations régissant la production renouvelable ont été obtenues
3

Automobilių stovėjimo aikštelių "Statyk ir važiuok" plėtros Viliniuje, panaudojant GIS, analizė / Analysis of „Park and ride“ parkings developement analysis in Vilnius, using gis

Barauskaitė, Greta 16 June 2014 (has links)
Pagrindinis magistro darbo tikslas – parengti „Statyk ir važiuok“ stovėjimo aikštelių įrengimo pagrindimo metodiką ir pateikti siūlymus dėl tokių stovėjimo aikštelių plėtros Vilniaus mieste. Darbo užduotys – atlikti literatūros šaltinių apžvalgą, išanalizuoti Vilniaus miesto specialiajame plane pateiktus „Statyk ir važiuok“ stovėjimo aikštelių įrengimo variantus, atlikti studentų bei ekspertų nuomonės tyrimus aikštelių įrengimo klausimais, nustatyti, kokios aikštelės yra tinkamiausios, pasitelkus statistinę skaičiavimo metodiką. Šiame darbe taikomi trys statistiniai metodai – SAW , TOPSIS ir COPRAS. Skaičiavimų metu, pagal tam tikrus parinktus kriterijus, apskaičiuojama, kurių iš siūlomų aikštelių įrengimas yra tikslingiausias. Studentų nuomonės tyrimo metu nustatytos devynios tinkamiausios aikštelės, o ekspertų nuomonės tyrimo metu nustatyta po tris tinkamiausias aikšteles periferinėje, vidurinėje ir centrinėje miesto zonose. Gauti tyrimų rezultatai gali būti panaudoti atsižvelgiant į tolesnę aikštelių plėtrą Vilniaus mieste. Darbo tekstine dalį turi sudaryti 78 p., 1–17 pav., 1–16 lent. ir 5 priedai, taip pat turi būti išanalizuoti 34 literatūros ir informacijos šaltiniai. Grafinę baigiamojo darbo dalį turi sudaryti 1 brėžinys: 1. Tinkamiausios „Statyk ir važiuok“ aikštelės Vilniaus mieste M 1:50 000. / The main aim of this masters work is to arrange „Park and ride“ parking spots installation method and to introduce proposals for parking spots development in Vilnius. The main assignment of this work is to analyze literature sources, to analyze "Park and Ride" sites which are listed in "Vilnius city special plan", to organize student and expert opinion survey about the "Park and Ride" sites development, to identify which of the sites are the best for Vilnius city, using multi-criteria analysis. In this job, three methods were used - SAW, TOPSIS and COPRAS. During the counting, several criteria are chosen to prove which site is the bests. In the student survey nine sites were declared as the most appropriate for the Vilnius. In the expert survey, there were three most appropriate sites in every region - periphery, middle city part and the center. The results of the survey can be used for further "Park and Ride" sites development in Vilnius. The work consists of the 78 pages of text, 17 figures 16 tables and 5 annexes as well as analysis of 34 literature and information sources. The graphical part of the thesis consists of 1 drawing: 1. The most appropriate “Park and Ride” sites for Vilnius M 1:50 000.
4

Alternativas para o transporte da areia e brita. / Alternatives for sand and crushed stone transportation.

Aguirre, Alberto de Barros 01 December 2008 (has links)
O presente trabalho versa sobre a possibilidade de redução de custos com a utilização de modais de transportes alternativos ao rodoviário, como o ferroviário e o hidroviário, para a obtenção de areia e brita, agregados para a construção civil de baixo preço, que têm volume de consumo bastante elevado, para sua disponibilização na cidade de São Paulo. As atividades de mineração assim como as demais atividades econômicas na era da globalização têm suas operações bastante semelhantes a níveis de custo, com pouca ou nenhuma possibilidade de redução, sem afetar diretamente a qualidade. O que se busca é identificar alternativas de ganho na competitividade por meio da redução de custos logísticos, única opção para atingir um melhor preço de venda. Para tanto, valeu-se de estudo das características e aplicabilidade das várias formas de transporte, como fator estratégico para a composição de custos adequados à competitividade desejada pelas empresas envolvidas na sua comercialização. Ao mesmo tempo, no emprego dessas alternativas de transporte, encontra-se a possibilidade de redução do congestionamento do tráfego e de melhoria na condição ambiental pela utilização de modais mais limpos. Trata-se de estudo de caso de natureza descritivo-exploratória do tipo quali-quantitativo com coleta de dados por meio de entrevista aberta, de pesquisa documental e bibliográfica. A discussão dos dados, oriundos das fontes primárias e da simulação permitiu chegar ao resultado que viabiliza a utilização do modal ferroviário a curto prazo e a utilização do hidroviário mais a longo prazo pela inexistência de infra-estrutura. O seu emprego resulta, além da redução de custos com frete, na melhoria do tráfego de veículos e na qualidade ambiental. / This work aims at focusing the possibility of cost reduction by the utilization of alternative means of transportation in relation to highways, railways and waterways in order to obtain sand and gravel, which are highly consumed, for civil construction at low added value to be available in São Paulo city. The mining activities as well as the other economic activities in the globalization era have very similar operations at cost level, having little or no possibility of reduction without directly affecting quality. What is searched is the identification of gain alternatives in competitiveness by reducing costs in logistics, it being the only option to reach a better sale price, by means of studying characteristics and applicability of various ways of transportation, as a strategic factor to compose adequate costs in relation to the competitiveness desired by the companies involved in their commerce. Likewise in the application of such alternatives of transportation there is a possibility of reducing traffic jams and improving the environmental condition by using cleaner means. It is a case study of descriptive-exploratory nature of the qualitative-quantitative type with collection of data in open interviews, documental and bibliographical research. The discussion of data coming from primary sources and from simulation made possible the result that makes viable the utilization of railway means in the short run and the utilization of waterway in the long run due to lack of infrastructure. Besides cost reduction in freight, its application brings improvement to traffic of vehicles and environmental quality.
5

Charging the use of studded tires in Stockholm city-A cost Benefit analysis / A cost Benefit analysis on the use of studded tires in Stockholm city

Aghanifor, Ishmael January 2015 (has links)
The stockholm county proposed legislation in 2010 on the use of studded tires in the city. The aim of the policy was to reduce the use of studded tires by 50 percent. The research question investigates the authenticity of the policy where it was hypothesized that the net social benefits for the imposition of this charge was less than or equal to zero. Emperical literatures were chosen systematically and with the help of theories on welfare economics, a meta analysis was employed quantifying cost and benefits of all outcomes. The findings shows that the NSB is less than zero meaning that it was a wise decision to reject the proposal.
6

Intégration dans le réseau électrique et le marché de l’électricité de production décentralisée d’origine renouvelable : gestion des congestions locales / Integration in the electrical grid and in the electricity market of dispersed generation from renewables : the local congestion problem

Vergnol, Arnaud 29 November 2010 (has links)
Le développement de la production éolienne permet de satisfaire les objectifs de lutte contre le réchauffement climatique. Cependant, dans certaines zones du réseau électrique, l’intégration d’un volume important de production peut créer des congestions qui traduisent l'incapacité du réseau à évacuer cette production. Les méthodes actuelles pour gérer les congestions sont basées sur des calculs prévisionnels de restrictions de production qui peuvent entrainer des pertes de production importantes pour le renouvelable. Cependant, dans le cadre d’un développement important du renouvelable, il est nécessaire de définir une méthodologie de gestion des congestions fiable, optimale du point de vue économique et non discriminatoire pour la production renouvelable.Dans le cadre de cette thèse, la méthodologie de gestion des congestions locales proposée repose sur l’usage d’un contrôle correctif. Le contrôle correctif est basé sur une boucle de régulation et un algorithme utilisant les réseaux de Petri. Une étude de stabilité de la boucle de régulation a montré que les marges de stabilité dépendantes des gains composant la boucle sont suffisantes. L’algorithme permet de définir les groupes de production à choisir pour la gestion des congestions en considérant leur coût d’utilisation et leur impact sur la congestion. Les essais, effectués sous le logiciel EUROSTAG, ont montré la pertinence de la méthodologie proposée et sa capacité à s’adapter à l’insertion des moyens de production. De plus, des conclusions générales sur les différents coûts associés à la gestion des congestions en fonction des différentes règlementations régissant la production renouvelable ont été obtenues / Development of wind generation is a mean towards global warming reduction. However, in some parts of the electrical grid, the massive integration of renewable generation can lead to congestion problems. These congestions are related to the impossibility for the power grid to transport the generation. Nowadays, congestion management methods are based on day(s)-ahead computation of generation restriction which leads to important production losses for renewables. Based on this context, it’s therefore important to develop a methodology which is optimal, reliable and non-discriminatory for renewable.In this work, the proposed congestion management method is based on corrective actions. These actions are computed in real-time using regulation loops and Petri net-based algorithms. A stability study proved that gain margins are sufficient to assure the stability of the corrective actions. The algorithm allows an optimal selection of the generators than will participate in the congestion management. This selection is based on their cost and efficiency for congestion alleviation. Simulation results using the software EUROSTAG have shown the efficiency of the method and its adaptability to different generator types. Furthermore, general conclusions on congestions costs according to different regulations on the renewable generation were obtained
7

Alternativas para o transporte da areia e brita. / Alternatives for sand and crushed stone transportation.

Alberto de Barros Aguirre 01 December 2008 (has links)
O presente trabalho versa sobre a possibilidade de redução de custos com a utilização de modais de transportes alternativos ao rodoviário, como o ferroviário e o hidroviário, para a obtenção de areia e brita, agregados para a construção civil de baixo preço, que têm volume de consumo bastante elevado, para sua disponibilização na cidade de São Paulo. As atividades de mineração assim como as demais atividades econômicas na era da globalização têm suas operações bastante semelhantes a níveis de custo, com pouca ou nenhuma possibilidade de redução, sem afetar diretamente a qualidade. O que se busca é identificar alternativas de ganho na competitividade por meio da redução de custos logísticos, única opção para atingir um melhor preço de venda. Para tanto, valeu-se de estudo das características e aplicabilidade das várias formas de transporte, como fator estratégico para a composição de custos adequados à competitividade desejada pelas empresas envolvidas na sua comercialização. Ao mesmo tempo, no emprego dessas alternativas de transporte, encontra-se a possibilidade de redução do congestionamento do tráfego e de melhoria na condição ambiental pela utilização de modais mais limpos. Trata-se de estudo de caso de natureza descritivo-exploratória do tipo quali-quantitativo com coleta de dados por meio de entrevista aberta, de pesquisa documental e bibliográfica. A discussão dos dados, oriundos das fontes primárias e da simulação permitiu chegar ao resultado que viabiliza a utilização do modal ferroviário a curto prazo e a utilização do hidroviário mais a longo prazo pela inexistência de infra-estrutura. O seu emprego resulta, além da redução de custos com frete, na melhoria do tráfego de veículos e na qualidade ambiental. / This work aims at focusing the possibility of cost reduction by the utilization of alternative means of transportation in relation to highways, railways and waterways in order to obtain sand and gravel, which are highly consumed, for civil construction at low added value to be available in São Paulo city. The mining activities as well as the other economic activities in the globalization era have very similar operations at cost level, having little or no possibility of reduction without directly affecting quality. What is searched is the identification of gain alternatives in competitiveness by reducing costs in logistics, it being the only option to reach a better sale price, by means of studying characteristics and applicability of various ways of transportation, as a strategic factor to compose adequate costs in relation to the competitiveness desired by the companies involved in their commerce. Likewise in the application of such alternatives of transportation there is a possibility of reducing traffic jams and improving the environmental condition by using cleaner means. It is a case study of descriptive-exploratory nature of the qualitative-quantitative type with collection of data in open interviews, documental and bibliographical research. The discussion of data coming from primary sources and from simulation made possible the result that makes viable the utilization of railway means in the short run and the utilization of waterway in the long run due to lack of infrastructure. Besides cost reduction in freight, its application brings improvement to traffic of vehicles and environmental quality.
8

Travel time estimation in congested urban networks using point detectors data

Mahmoud, Anas Mohammad 02 May 2009 (has links)
A model for estimating travel time on short arterial links of congested urban networks, using currently available technology, is introduced in this thesis. The objective is to estimate travel time, with an acceptable level of accuracy for real-life traffic problems, such as congestion management and emergency evacuation. To achieve this research objective, various travel time estimation methods, including highway trajectories, multiple linear regression (MLR), artificial neural networks (ANN) and K –nearest neighbor (K-NN) were applied and tested on the same dataset. The results demonstrate that ANN and K-NN methods outperform linear methods by a significant margin, also, show particularly good performance in detecting congested intervals. To ensure the quality of the analysis results, set of procedures and algorithms based on traffic flow theory and test field information, were introduced to validate and clean the data used to build, train and test the different models.

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