• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 71
  • 26
  • 10
  • 9
  • 6
  • 4
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 149
  • 149
  • 34
  • 31
  • 29
  • 21
  • 20
  • 18
  • 18
  • 18
  • 18
  • 16
  • 15
  • 15
  • 15
  • 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.
121

Agrégation de trafic pour réduire la consommation énergétique globale dans les réseaux sans fil multi-sauts / Traffic aggregation for global energy savings in multi-hop wireless networks

Laubé, Alexandre 25 September 2017 (has links)
Les incitations économiques et environnementales poussent dorénavant à intégrer des considérations énergétiques dès les premiers stades de développement des réseaux. Dans les réseaux sans fil multi-sauts, l'approche la plus courante consiste à répartir le trafic sur l'ensemble des nœuds afin de réduire équitablement la consommation énergétique de chacun, avec pour objectif la maximisation de la durée de vie du réseau. Or cette approche n'est pas optimale vis-à-vis de la consommation globale du réseau, le niveau d'activité d'un nœud n'ayant souvent que peu d'influence sur sa propre consommation. Nous montrons que la meilleure approche consiste à éteindre un maximum de nœuds. Parmi les travaux réalisés, nous avons développé une solution s'appuyant sur de la programmation linéaire en nombres entiers et des simulations de graphes et de réseaux. La solution proposée permet ainsi une agrégation de flux optimale, réduisant significativement le nombre de nœuds utilisés dans le réseau. Afin de la rendre applicable en pratique, une heuristique est détaillée permettant une mise en œuvre distribuée grâce à l'utilisation d'une métrique de routage. Ainsi, tout algorithme de plus court chemin peut nativement réaliser de l'agrégation de flux efficace. Il est important de souligner que la qualité de service en termes de débit est respectée. En effet, les interférences sont prises en compte et il est possible de profiter de la synergie offerte par l'utilisation conjointe de l'agrégation de flux et du codage réseau. Nos résultats améliorent significativement les méthodes d'économie d'énergie basées sur l'extinction des nœuds en leur permettant d'en éteindre davantage. / Economic and ecologic incentives are now leading people to design networks with energetic considerations at early stages of development. Most of the works for multi-hop wireless networks tend to spread the traffic uniformly over the network to reduce the energy consumption of each node individually. However, considering that the traffic of a node doesn't impact significantly its energy consumption, this approach is not optimal regarding the global energy consumption of the network. Finding a way to turnoff as much node as possible seems then to be a better way. This PhD thesis focus on routing a set of flows over a multi-hop wireless network while minimizing the number of used nodes. This is done by using a distributed metric that allows the shortest path routing algorithms to perform flow aggregation. Using integer linear programming and simulations, we proposed an efficient solution to aggregate flows to significantly reduce the number of nodes used in the network. It allows, then, to improve algorithms that reduce the energy consumption of networks by increasing the number of nodes that can be turned off.
122

Posouzení možnosti využití alternativních zdrojů v energetickém hospodářství výrobního areálu / Possibility of using alternative sources of energy in manufacturing facility

Malchar, Jakub January 2017 (has links)
The Master’s Thesis prospects the suitability of installing a photovoltaic system and a cogeneration unit in the LIPOELASTIC manufacturing facility and proposes their actual realization. Theoretical part describes said facility, its current energy supply situation and presents the proposed realizations' principle of operation. Practical part contains concrete calculations needed for realizations' proposal and their economic evaluation both independently and jointly.
123

Ekonomická analýza optimalizace budov / Economic analysis of building optimization

Pospíchalová, Barbora January 2019 (has links)
The Master’s thesis deals with the energy savings of a prefabricated house. In the theoretical part, the issue of investment and risk management are first dealt with. Afterwards, the thesis deals with large panel construction in the Czech Republic, energy performance of buildings, heat losses, and especially methods for invesment appraisal. The main objective of the thesis is the economic analysis and the life-cycle analysis. The case study deals with the calculation of saving on heating the prefabricated house after its refurbishment and calculation of economic indicators.
124

Optimální využití energie a vody v aquaponické farmě / Resource optimisation in the indoor aquaponic farm

Ondruška, Vojtěch January 2020 (has links)
Energetická náročnost a ekonomická životaschopnost jsou často skloňované pojmy spojené s aquaponickým způsobem produkce potravin. Tato práce si klade za cíl nalézt opatření, která by zvýšila ziskovost podnikání v oblasti aquaponie a zároveň by snížila energetickou náročnost procesu a spotřebu dalších zdrojů. Součástí práce je následné ověření vybraných opatření na zkušební aquaponické farmě. K vyřešení otázky úspory energie a vody byly použity optimalizační metody vycházející z procesního inženýrství. Pro účely automatického monitoringu růstu rostlin, jakožto hlavního zdroje příjmů v aquaponii, byla využita technologie počítačového vidění. Za využití optimalizační metody zvané P-graph, integrace procesů a hledání procesních alternativ bylo nalezeno nejlepší možné uspořádání procesní sítě, které vykazovalo více než devítinásobný čistý roční příjem ve srovnání se současným uspořádáním procesních zařízení v aquaponické farmě. Dalších úspor energie a vody bylo dosaženo instalací reflexních fólií na okraje pěstebních boxů a dalším využitím odpadní vody z aquaponické části farmy v hydroponické sekci určené k pěstování sazenic. Tato opatření mohou napomoci aquaponickým farmám zvýšit konkurenceschopnost a snížit jejich dopad na životní prostředí.
125

Studie proveditelnosti - zavedení nového produktu na trh - zelené úvěry / Feasibility Study - Entry of New Product Into the Market - Green Credits

Jungwirth, Michal January 2010 (has links)
This diploma thesis describes by a feasibility study the introduction of a new product, which has the name Green credits. This project responds to a flexible manner on a prospective and dynamically growing market for environmentally friendly and energy-saving solutions and its implementation may allow a particular financial institution to obtain the position of leader and new business in this market.
126

Energetická optimalizace polyfunkčního objektu / Energy optimization of multifunctional building

Rulíšková, Pavla January 2014 (has links)
Contain of master´s thesis is a energy assessment of multifunctional building in Komňátka. The theoretical part deals with the analysis of legislativ documents, current technical solution and practical application to the specified building. In the practical part thesis focus on experimental determination of the heat transfer coefficient using thermography.
127

Studium pasivní radiace povrchových úprav ve stavebnictví / The study of passive radiation finishes in construction

Kopkáně, Daniel Unknown Date (has links)
One of the key issues of our society is to decrease energy demand. About 40 % of energy consumption in Europe is related to building operation, mostly for heating. The required thermal comfort is related mainly to temperature of air and temperature of surrounding surfaces. Especially in older buildings with low level of thermal insulation the inner surface of perimeter wall can be several degrees colder than air. In such case the perception of thermal comfort will be lowered also depending on the layout of the room. Other issue can be related to thermal radiation asymmetry. The amount of energy that is eradiated from a surface is driven by material property called emissivity. A surface with sufficiently low emissivity will became “thermal mirror”. It is possible to elaborate about intelligent thermal management of the internal space with usage of low-emissive surfaces; where thermal radiation can be suppressed or can be enhanced. This depends on the surface emissivity and its real temperature. Recently, growing interest about the low-emissive surfaces can be seen. They can represent reasonable complement to conventional insulation, but they have certain limits. Potentially, even higher energy savings can be reached with so called retro reflection. If the thermal radiation of an object is reflected back, its thermal loss will be lower. In such case it can be expected that equivalent thermal comfort can be reached even with lower overall temperature of the room. The aim of the work is study of material combinations with potential for utilization as low-emissive interior surfaces. Research has been conducted on low-emissive paints and low-emissive foils. Another part of the work is related to retro reflection of thermal radiation as a potential way to influence thermal comfort. The work shows, that energy saving up to 20% can be obtained.
128

Energetický audit vodovodů / Energy Audit od Water Supply Systems

Krupa, Filip January 2016 (has links)
This Disertation deals with energetical audit of aqueduct. First part is dedicated to the current status in Czech Republic, but expecially abroad. Other part processes structure of energetical audit according to the knowledge gained and also from academic articles and set up an example, where this audit is made. Firts variant is energetically intensive water line and other variant is nergetically economical. Last part id dedicated to perform an energetical audit on real water line in Kateřinice village, Vsetín district.
129

Optimalizace nákladů provozní fáze stavebních objektů / Cost optimization of the operational phase of buildings

Kleinerová, Jana January 2016 (has links)
The thesis discusses the operating costs and the possibilities for their optimization. Specifically, it focuses on one of the greatest possible operating costs and it's heating costs. In the first part of the thesis are defined in general expenses, the price and the production, operating costs, optimization of these costs, life cycle of buildings and technological methods to improve the thermal and technical properties of the object. Finally, the theoretical part describes the terms for calculating the energy performance of the building and the payback period, which evaluates the effectiveness of investments. The practical part is assessed according to specific building energy performance, and especially in terms of its demand for heating. The building is designed for six variants of insulation, which is again judged on their energy performance. Subsequently these measures for better thermal insulating properties of the object assessed according to their cost efficiency and return on investment of individual variants.
130

Posouzení ekonomické efektivnosti nízkoenergetického a pasivního domu / Assessment of the economic efficiency of low-energy and passive house

Maixner, Lukáš January 2016 (has links)
The aim of this diploma thesis is to assess the economic efficiency of alow-energy and passive construction. This paper presents problems of lowenergy and passive construction, their individual characteristics, classification, construction materials, evaluation methods and opportunities for economic assessment due to the investment costs of implementation objects. The main practical part focuses on comparing the investment and operating costs for the construction of a standard, low-energy and passive house. Together with this are processed simple labels building. The out come of this diploma thesis is the calculation of returnability increased by the initial investment in the construction of a standard, low-energy and passive house.

Page generated in 0.082 seconds