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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Otimização de recursos e economia de energia em clusters usando virtualização. / Resource optimization and energy saving in clusters using virtualization.

Marcus Vinícius do Patrocínio Azevedo 19 July 2010 (has links)
Este trabalho propõe uma arquitetura reutilizável que permite a gerência de uma infraestrutura de suporte para aplicações Web, utilizando máquinas virtuais. O objetivo da arquitetura é garantir qualidade de serviço, atuando nos servidores físicos (hospedeiros) ou manipulando as máquinas virtuais, e avaliando o cumprimento das restrições de operação (tempo de resposta máximo). Além disso, através do uso racional dos recursos utilizados, a proposta visa à economia de energia. O trabalho também inclui uma avaliação de desempenho realizada sobre um sistema implementado com base na arquitetura. Esta avaliação mostra que a proposta é funcional e o quanto ela pode ser vantajosa do ponto de vista do uso de recursos, evitando desperdício, mantendo-se ainda a qualidade de serviço em níveis aceitáveis pela aplicação.
142

Dimensionnement et optimisation des réseaux de collecte sans fil / Design and optimization of wireless backhaul networks

Kodjo, Alvinice 18 December 2014 (has links)
L’essentiel des travaux de cette thèse porte sur les réseaux de collectes de données sans fil. Nous avons étudié différents problèmes d’optimisation dans ces réseaux qui représentent de vrais challenges pour les industriels du secteur. Le premier problème porte sur l’allocation de capacités sur les liens à coût minimum. Il a été résolu par une approche de programmation linéaire avec génération de colonnes. Notre modèle permet de résoudre des problèmes de grandes tailles. Nous avons ensuite étudié le problème du partage d’infrastructure réseau entre opérateurs virtuels avec comme objectif de maximiser les revenus de l’opérateur de l’infrastructure physique tout en satisfaisant les demandes et les contraintes de qualité de service des opérateurs virtuels clients du réseau. Dans ce contexte, nous avons proposé une formulation robuste du problème en programmation linéaire en nombres entiers mixte. Un autre point de dépenses dans ce type de réseau est la consommation d’énergie. Nous avons proposé une solution robuste, de routage basée sur la consommation d’énergie du réseau. Notre solution a été formulée en utilisant un programme linéaire en nombre entiers mixte. Nous avons aussi proposé des heuristiques afin de trouver assez rapidement des solutions pour de grandes instances. Le dernier travail de cette thèse porte sur les réseaux radio cognitifs et plus précisément sur le problème de partage de bande passante. Nous l’avons formalisé en utilisant un programme linéaire mais avec une autre approche d’optimisation robuste. Nous utilisons la méthode d'optimisation robuste à 2 niveaux pour le résoudre. / The main work of this thesis focuses on the wireless backhaul networks. We studied different optimization problems in such networks that represent real challenges for industrial sector.The first issue addressed focuses on the capacity allocation on the links at minimum cost. It was solved by a linear programming approach with column generation. Our method solves the problems on large size networks. We then studied the problem of network infrastructure sharing between virtual operators. The objective is to maximize the revenue of the operator of the physical infrastructure while satisfying the quality of service constraints of virtual operators customers of the network. In this context, we proposed a robust model using mixed integer linear programming. In the following problem, we proposed a robust energy-aware routing solution for the network operators to reduce their energy consumption. Our solution was formulated using a mixed integer linear program. We also proposed heuristics to find efficient solutions for large networks. The last work of this thesis focuses on cognitive radio networks and more specifi- cally on the problem of bandwidth sharing. We formalized it using a linear program with a different approach to robust optimization. We based our solution on the 2-stage linear robust method.
143

A influência da modernização do sistema de controle de trens no consumo de energia no metrô de São Paulo / The influence of the train control system modernization on the consumption of energy São Paulo metro

Gomes, Francisco Moraes 23 June 2017 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-08-09T18:45:01Z No. of bitstreams: 1 Francisco Moraes Gomes.pdf: 3240990 bytes, checksum: 17659c72fed5b3faf44d712b20b24e39 (MD5) / Made available in DSpace on 2018-08-09T18:45:02Z (GMT). No. of bitstreams: 1 Francisco Moraes Gomes.pdf: 3240990 bytes, checksum: 17659c72fed5b3faf44d712b20b24e39 (MD5) Previous issue date: 2017-06-23 / The aim of this research is to study the potential association between the reduction in electricity consumption in Line 2 – Green of the São Paulo Subway and the change of the Train Control System from the "fixed block" type to the "moving block" type. This study is necessary because the transport sector is one of the biggest consumers of energy and the energy is one of the highest costs of the metro system, so that any reduction must be studied and understood. Most of the previous studies published on energy efficiency at subways and trains are simulation studies, there is a few literature based on empirical data. The statistical approach was chosen because there is no installed equipment to directly measure this influence, since there are only measures of consumption at the entrances of the System and there is no individual measurement of each train. Part of the data used was obtained via official communication channels of the company, another part was obtained directly from the operational reports and other data was extracted from the capture of the communications between the trains and centralized control system. Several variables that can influence the consumption of the line and also the train speed profiles in the periods just before and after the System change have been verified. The study of the relationships among these variables was done and the multivariate regression analysis was performed. The results of the regression generated an equation model with significance for the variables: type of system, proportion of useof the fleets used and the number of trips made. In the regression process, the stepwise method was used and some variables were withdrawn when verifying that they had multicollinearity. The data extracted from the communication protocol were not used in the regression, but they did allow verifying an evidence of improvement in the speed profiles and also a reduction in the number of stops that the train made in the route, indicating a smaller interference between the train movements with the new system. The calculated savings obtained by the new system was around 2.8%, rising to about 7.8% on average when the new fleet was included, which only uses the "moving block" system. / Esta pesquisa tem por objetivo estudar a potencial associação da ocorrência de queda no consumo de energia elétrica na Linha 2-Verde do Metrô de São Paulo com a troca do Sistema de Controle dos Trens do tipo “bloco fixo” para o tipo “bloco móvel”. Este estudo se mostra necessário, pois o setor de transporte é um dos maiores consumidores de energia e a energia é um dos maiores custos do sistema metroviário, de forma que qualquer redução deve ser estudada e compreendida. A maioria dos estudos anteriores publicados sobre eficiência energética em metrôs e trens são estudos de simulação, havendo pouca literatura baseada em dados empíricos. A abordagem estatística foi escolhida porque não há equipamentos instalados para se medir diretamente essa influência, pois apenas há medida de consumo somente na entrada de energia do Sistema, e não medição individual de cada trem. Parte dos dados utilizados foi obtida via canais oficias de comunicação da companhia, outra parte foi obtida diretamente dos relatórios operacionais e outros dados foram extraídos da captura das comunicações entre os trens e sistema de controle centralizado. Foram verificadas diversas variáveis que podem influir no consumo da linha e também os perfis de velocidades dos trens nos períodos imediatamente anteriores e posteriores a troca do Sistema. Foi realizado o estudo das relações entre essas variáveis e feita análise por regressão multivariada. Os resultados da regressão geraram um modelo de equação com significância para as variáveis: tipo de sistema, proporção de uso uma das frotas e a quantidade de viagens realizadas. No processo de regressão foi usado o método stepwise e algumas variáveis foram retiradas ao verificar que apresentavam multicolinearidade. Os dados extraídos do protocolo de comunicação não foram usados na regressão, mas por meio deles foi possível verificar indícios de melhoria nos perfis de velocidade e também uma redução na quantidade de paradas que o trem realizava no percurso, indicando uma menor interferência entre as movimentações dos trens com o novo sistema. A economia calculada obtida pelo novo sistema ficou em torno de 2,8%, subindo para cerca de 7,8% em média ao se incluir a nova frota, a qual só utiliza o sistema de "bloco móvel".
144

Vplyv energetických opatrní na ceny prevádzky budovy / The Impact of Energy Saving Measures on Prices of Building Operation

Kabzáni, Matej January 2017 (has links)
The theme of the diploma thesis "Effect of energy care on building prices" is the design and assessment of several measures, two of which generally lead to lower heating costs. The diploma thesis deals with evaluation of the current state of the family house and determination of PENB before the construction modifications and subsequently after the construction modifications, defining subsequent measures for energy saving implementation, both in terms of energy, economic and also environmental.
145

Hodnocení budovy formou energetického auditu / Evaluation of the building form an energy audit

Blažek, Tomáš January 2018 (has links)
The aim of this master's thesis is elaborating energy audit within current notice 480/2012. The first part of master's thesis deals about history of distrit heating, methods of connection handover, advantages and disadvantages of district heating.The second part analyses consuption energy of assessing bulding. The third part is energy audit.
146

Porovnání vybraných cenových podílů u energeticky úsporných domů / Comparing Selected Price Shares for Energy-saving Houses

Drkošová, Dominika January 2018 (has links)
This thesis compares prices of shares of construction of buildings for five energy-saving family houses calculated by public notice with the prices gathered in an itemized budget.
147

Energetická optimalizace administrativní budovy / Energy optimization of the administrative building

Černý, Tomáš January 2019 (has links)
The diploma thesis deals with the energy audit of administrative building. In the theoretical part I described the heat pumps. In a calculated part I proposed austerity measures and created of them saving variant. I chose the most suitable variant and assess it from an economic and ecological point of view. In the third part, I use the calculation program to optimize the building.
148

Energetické hodnocení administrativní budovy / Energy evaluation of office building.

Lysková, Markéta January 2017 (has links)
This diploma thesis is dealing with energy audit of industrial building with administration part, situated in Blansko, South Moravia region. The theoretical part is focused to windows from the energy balance point of view, because one of the energy saving measures is the change of current insufficient window filling. The main objective of this diploma thesis is to find the most energy saving variant which is going to be evaluated from the both, ecological and economical, aspect. The third part is dedicated to usage of computer technology as software for 3D model creating of assessed building or energy consumption simulation for particular systems as heating in relation to characters of different kinds of windows.
149

Innovative industrielle Erdgasbeheizungssysteme auf der Basis der Porenbrennertechnologie für Hochtemperaturanwendungen

Reusse, Ekaterina 20 November 2012 (has links)
Im Rahmen der Dissertation wurde ein vollkeramischer Porenbrenner entwickelt, der im Bereich hoher Prozesstemperaturen eingesetzt werden kann. Die Brennerentwicklung umfasste die Entwicklung und Auswahl von geeigneten Komponenten wie ein Gehäuse und eine Flammensperre sowie die Anpassung an die Brennergeometrie. Die entwickelten Porenbrenner wurden Tests im Freibrand und im Hochtemperaturofen im Labor unterzogen. Eine entscheidende Rolle für die Bewertung des Brennersystems spielte die Qualifizierung unter Realbedingungen. Das Brennersystem wurde in Ofenanlagen zur Glasherstellung eingesetzt. Durch die Versuche in einer Arbeitswanne für die Herstellung von Behälterglas und in einer Vorwärmtrommel für die Herstellung von Kunstglas wurde der Nachweis der Industrietauglichkeit erbracht. Es wurden dabei die Vorteile wie Energieeinsparnis, verbesserte thermische Homogenität und niedrige CO- und NOx-Emissionen gezeigt.
150

Energimodellering av ett flerbostadshus  - en parameterstudie : Granskning av energianvändning och termisk komfort / Energy simulation of a multi-apartment building  - a parameter analysis : Evaluation of energy performance and thermal comfort

Saidzadeh, Millad January 2013 (has links)
Idag står bostads- och servicesektorn för närmare 40 % av Sveriges totala slutliga energianvändning. Flerbostadshus utgör ca 30 % av den energianvändningen. Därför är det viktigt att lokalisera energiparametrar och redovisa dess betydelse för energianvändningen. Samtidigt bör relationen mellan energianvändning och inomhusklimat analyseras, så att inte förändringar i energin medför till försämringar för inomhusklimatet. Baserat på identifiering hos energisparpotentialen hos parametrar, parameterbeteende och parameterkänslighet för energianvändning har i studien ett antal parametrar undersökts för ett flerbostadshus. Även parametrarnas betydelse för det termiska klimatet har utifrån de parametrar som visat sig ha störst energisparpotential studerats. Studien är tänkt att komma till nytta för presentation av energisparpotentialer och beaktande hos indataparametrar vid energiberäkningar, samt öka förståelsen för hur termiska komforten påverkas av olika parametrar. En referensbyggnad har modellerats i programmet IDA ICE 4.5 och typisk spridningen för olika parametrar för byggnader från år 1970 till nutid har varierats och jämförts med ett referensfall. För det termiska klimatet har kriterier enligt certifieringsprogrammet Miljöbyggnad utnyttjats. Resultatet visar att ventilationssystem har stor energisparpotential. Vid en övergång från F-system till FTX-system görs betydande energibesparing, samtidigt som det sker en förbättring av den termiska komforten. Inomhustemperaturen har visats sig vara den känsligaste parametern vid beräkning av energianvändning. För den termiska komforten är fönsters g-värde och inomhustemperatur viktiga parametrar att beakta. Resultatet av energi- och komfortsimuleringarna visar också på en tydlig korrelation mellan energianvändning och termisk komfort. / Building stock consumes 40 % of total energy usage in Sweden, dwellings contribute almost 30% of the proportion. With an interest on the parametric analysis and its corresponding energy saving potentials, the investigation on the sensitivity of selected building parameters in a typical Swedish slab house is performed in the study. Based on the identification to the behavior of target sensitive parameters, the upgrading potential of thermal comforts is comparably analyzed with respect to approach the optimization design of further retrofitting scenario and uncertainty guidelines. A slab house built after 1970 is selected as the represented case building with a detailed typology introduction. In the study, IDA ICE 4.5 is applied to perform both the energy simulation and thermal comfort estimation. Based on the local screening analysis and the setting of criterion system, the ranking of the target parameters is rated systematically. The study is meant to be useful for the presentation of energy saving potentials and consideration of input parameters on energy calculations, and increase understanding of how thermal comfort is affected by various parameters. The results show that accomplished with the transformation of F-system to FTX-system, the applicable ventilation system efficiency shows the largest energy saving potential and improved thermal comfort, and the indoor temperature shows the largest sensitivity to the total energy profile. Comparably, along with the indoor temperature, the performance of glazing system in terms of the g-value is recognized as the parameters with the highest consideration. Based on the sensitivity analysis, the correlation between the energy savings and thermal comfort upgrading is verified, which indicate the possibility of providing optimal design scenario for both architectural error guidelines and further building retrofitting.

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