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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.
161

Технологии "Пассивного дома" и возможность применения в Уральском федеральном округе : магистерская диссертация / "Passive House" technologies and the possibility of their use in the Ural Federal District

Potapov, I. E., Потапов, И. Е. January 2014 (has links)
The aim of this master's thesis is to find out the possibility of building a passive house in the Ural region. To achieve this goal it was necessary to solve the following problems, the results are presented in the thesis: 1) to define the concept of "passive house"; 2) to identify the technologies used under the construction of energy efficient buildings; 3) to consider the alternative mounting options of low-rise buildings; 4) to establish the geographic and climatic conditions of the selected area; 5) to describe the socio-economic situation in the region; 6) to reveal the specifics of the Passive House in the Ural Federal District. It was found out that construction of a Passive House in compliance with all the relevant technologies and global standards of Passive Houses in the climatic conditions of the Ural region at this stage is difficult. The main reasons of that are the following: 1) The climatic conditions of the region require for increasing the insulation layer, development and application of new types of insulating materials with higher resistance to heat transfer. 2) The economic conditions of the region determine the choice in favor of budget accommodation rather than innovation. 3) The complexity of the design, the lack of professionals and practical experience in the construction of passive houses. Master's thesis contains 62 pp., 6 fig. 5 tab., 67 bibliographic references. Graphic part - 5 sheets. / Цель диссертации - определить возможность постройки пассивного дома в Уральском регионе. Для реализации поставленной цели необходимо было решить следующие задачи, результаты изложены в диссертации: 1) определить понятие "Пассивный дом"; 2) обозначить технологии, применяемые при строительстве энергоэффективных зданий; 3) рассмотреть альтернативные возможности монтажа малоэтажных строений; 4) установить географо-климатических условия выбранной территории; 5) описать социально-экономическую ситуацию заданного региона; 6) выявить специфику пассивного дома для Уральского федерального округа. Установлено, что постройка пассивного дома с соблюдением всех технологий и соответствующего общемировым стандартам пассивного дома на данном этапе в климатических условиях Уральского региона затруднительна. Основными причинами этого являются: 1) Климатические условия региона, требующие увеличения слоя изоляции, разработки и применения новых видов изолирующих материалов с большим сопротивлением теплопередаче. 2) Экономические условия региона, определяющие выбор в пользу бюджетного жилья, нежели инновационного. 3) Сложность конструкции, отсутствие специалистов и практического опыта строительства пассивных домов. Магистерская диссертация содержит 62 с., 5 табл., 6 рис., 67 библиограф. ссылок. Графическая часть – 5 л.
162

Внедрение энергоэффективных технологий и инновационных материалов в малоэтажное жилищное строительство как фактор повышения качества строительства : магистерская диссертация / Introduction of energy-efficient technologies and innovative materials in low-rise housing construction as a factor of improving the quality of construction

Асманкина, А. Н., Asmankina, A. N. January 2019 (has links)
Магистерская диссертация состоит из введения, трех глав, заключения, списка литературы и приложения. В работе рассматривается концепция современных каркасных домов по финской технологии, которая пришла к нам с северных широт американского континента, где они являются самым распространенным вариантом частного жилья. В качестве ключевого доказательства выделяются конструкционные особенности «зеленых домов», которые характеризуются высокими теплоизоляционными качествами с доступной стоимостью и оптимальным сроком возведения. Описываются характерные особенности этапов строительства каркасных домов и уделяется внимание материалу, из которого собираются данные конструкции. Проведен макроэкономический анализ показателей Свердловской области и города Кушва, приведена характеристика города и анализ внешнеэкономического окружения. Предложен проект реализации инвестиционно-строительного проекта каркасного коттеджного поселка, позволяющий удовлетворить потребность жителей города в индивидуальном жилье. В заключении сформулированы основные выводы и результаты диссертационного исследования. / The master's thesis consists of an introduction, three chapters, a conclusion, a list of references and an Appendix. The paper discusses the concept of modern frame houses on the Finnish technology, which came to us from the Northern latitudes of the American continent, where they are the most common option of private housing. The key evidence is the structural features of "green houses", which are characterized by high thermal insulation qualities with affordable cost and optimal construction time. The characteristic features of the stages of construction of frame houses are described and attention is paid to the material from which these structures are collected. The macroeconomic analysis of indicators of the Sverdlovsk region and the city of Kushva is carried out, the characteristic of the city and the analysis of the external economic environment is given. The project of realization of investment and construction project of the frame cottage settlement allowing to satisfy need of inhabitants of the city in individual housing is offered. In conclusion, the main conclusions and results of the dissertation research are formulated.
163

Optimization of Energy Efficient Windows in Office Buildings for Different Climate Zones of the United States

Rathi, Priyanka 30 April 2012 (has links)
No description available.
164

Improving Energy Efficiency of Network-on-Chips Using Emerging Wireless Technology and Router Optimizations

DiTomaso, Dominic F. 25 July 2012 (has links)
No description available.
165

Lessons Learned in Energy Efficiency of Mini-Split HVAC Systems in Affordable Housing

Ebrahim, Fatemah Mohammad 10 February 2021 (has links)
The road to energy-efficient housing is not without cracks and potholes. Many building stakeholders have pointed to the discrepancies that exist between simulated and measured efficiency results, where some have called it a post-occupancy gap, others have called it an energy efficiency information gap. The research presented in this thesis addresses that gap by detailing the results of two exploratory case studies of affordable housing projects in Virginia across three manuscripts. The data utilized in the first manuscript includes measured data collected at the second level through the NEXI energy monitoring and feedback device, wherein we used descriptive statistics to investigate the impact of temperature on energy use over different timeframes. We had anticipated our findings may not all be consistent with previously existing studies. We found this to be true in many cases, but we also discovered interesting contradictions to our assumptions. This study thereby investigates the gap in energy performance within net-zero buildings and contributes to the existing body of literature by presenting the findings of this unique study. The data utilized in Manuscript 2 and Manuscript 3 was utility data, which was reported as end-of-use monthly consumption values. We were able to investigate the impact of 3 different HVAC systems energy use by evaluating the energy and cost performance before and after the installation of newer, more efficient systems. We found that although all systems were performing below anticipated standards, the one-stage system outperformed in terms of efficiency, and the second-stage system outperformed in terms of cost. The findings in these studies emphasize the importance of energy education for residents to achieve greater efficiency gains. / Master of Science / Humans are complex beings; hence the buildings they inhabit are complex systems. While breakthroughs in simulating, designing, and constructing high-performance buildings as well as advanced energy use technologies have been promising, many have fallen short of their ambitious goals primarily due to the complexity of building occupant behavior. Achieving energy efficiency requires thorough research before design and construction, the use of advanced technologies, and the incorporation of behavior-driven energy use dynamics. Furthermore, with the breadth of literature to support the delivery of individualized energy information in real-time to residents comes the opportunity to investigate further the impact of advanced technologies in high performing buildings that have fallen short of their optimistic design goals. This thesis consists of three manuscripts, which describe two exploratory case studies of high-performance residential homes in Virginia's affordable housing sector. The first manuscript, a journal paper, investigates the individual HVAC energy use of six senior residents, wherein we explore the interplay between temperature, energy use, and age across different timeframes. We find that, across different timeframes, energy use for senior citizens remains relatively consistent in high-performance homes. The second and third manuscripts are conference papers, which have been presented on and published in the respective conference proceedings. We quantitively investigated the energy performance of energy-efficient HVAC systems and compared predicted results and measured results. In conclusion, we hope to contribute to the body of literature, which investigates shortcomings in achieving energy-efficiency within high-performance homes.
166

Energy-efficient privacy homomorphic encryption scheme for multi-sensor data in WSNs

Verma, Suraj, Pillai, Prashant, Hu, Yim Fun 04 May 2015 (has links)
Yes / The recent advancements in wireless sensor hardware ensures sensing multiple sensor data such as temperature, pressure, humidity, etc. using a single hardware unit, thus defining it as multi-sensor data communication in wireless sensor networks (WSNs). The in-processing technique of data aggregation is crucial in energy-efficient WSNs; however, with the requirement of end-to-end data confidentiality it may prove to be a challenge. End-to-end data confidentiality along with data aggregation is possible with the implementation of a special type of encryption scheme called privacy homomorphic (PH) encryption schemes. This paper proposes an optimized PH encryption scheme for WSN integrated networks handling multi-sensor data. The proposed scheme ensures light-weight payloads, significant energy and bandwidth consumption along with lower latencies. The performance analysis of the proposed scheme is presented in this paper with respect to the existing scheme. The working principle of the multi-sensor data framework is also presented in this paper along with the appropriate packet structures and process. It can be concluded that the scheme proves to decrease the payload size by 56.86% and spend an average energy of 8-18 mJ at the aggregator node for sensor nodes varying from 10-50 thereby ensuring scalability of the WSN unlike the existing scheme.
167

Case Study of the Energy Performance of a School Building Before and After Renovation

Gurudas, Salu, Shaji, Pooja January 2024 (has links)
Improving energy efficiency in buildings is essential for curbing greenhouse gas emissions, addressing climate change, and achieving cost savings while enhancing occupant comfort. This study examines the energy performance of Nordiska Folkhögskolan, a Swedish school building, before and after renovation, benefiting from Sweden's advanced energy-efficienttechnologies and supportive policies. Energy consumption data analysis reveals significant reductions in district heating and electricity usage post-renovation, attributed to enhancements in insulation, heating systems, and energy management. Notably, there is a consistent decline in energy consumption, particularly during winter months, emphasizing the effectiveness of holistic approaches to energy-efficient building design and highlighting the importance of targeted energy efficiency measures in reducing heat losses through the building envelope.  The successful mitigation of energy loss through enhanced insulation and ventilation systems underscores the necessity of comprehensive energy-efficient design strategies. Despite promising outcomes, variations in energy consumption patterns post-renovation require ongoing evaluation and supplementary measures. Recommendations include adopting advanced exterior wall designs, continuous energy monitoring, integrating renewable energy solutions, conducting educational outreach initiatives, and investing in energy-efficient infrastructure. These strategies collectively promote conservation and establish sustainable learning environments, contributing valuable insights into enhancing energy efficiency in school buildings globally.
168

Energy-Efficient, Utility Accrual Real-Time Scheduling

Wu, Haisang 29 August 2005 (has links)
In this dissertation, we consider timeliness and energy optimization in battery-powered, mobile embedded real-time systems. We focus on real-time systems that operate in environments with dynamically uncertain properties, including context-dependent activity execution times and arbitrary activity arrival patterns. We consider an application model where activities are subject to time/utility function (or TUF) time constraints, mutual exclusion constraints on concurrent sharing of non-CPU resources, timeliness requirements including assurances on individual activity timeliness behavior, and system-level energy consumption requirements including a non-exhaustable energy budget. To account for uncertainties in activity properties in dynamic systems, we stochastically describe activity execution demands, and describe activity arrival behaviors using the unimodal arbitrary arrival model, which allows unbounded arrival frequencies. We consider the scheduling optimality criteria of: (1) probabilistically satisfying lower bounds on individual activities' maximal timeliness utilities, and (2) maximizing system-level energy efficiency, while ensuring that the system's energy consumption never exhausts the energy budget and resource mutual exclusion constraints are satisfied. For this multi-criteria scheduling problem, we present a DVS (dynamic voltage scaling)-based, real-time scheduling algorithm called the Energy-Bounded Utility Accrual Algorithm (or EBUA). Since the scheduling problem is NP-hard, EBUA heuristically (and dynamically) allocates CPU cycles to activities, computes activity schedules, and scales CPU voltage and frequency with a polynomial-time cost. If activities' cumulative execution demands exceed the available CPU time or may exhaust the system's energy budget, the algorithm defers and rejects jobs in a controlled fashion, minimizing system-level energy consumption and maximizing total accrued utility. We analytically establish several properties of EBUA. We prove that the algorithm never exhausts the specified energy budget. Further, we establish EBUA's timeliness optimality during under-loads, freedom from deadlocks, and correctness in mutually exclusive resource sharing. In particular, we prove that the algorithm's timeliness behavior subsumes the optimal timeliness behavior of deadline scheduling as a special case, and identify the conditions under which lower bounds on individual activity utilities are satisfied. In addition, we upper bound the time needed for mutually exclusively accessing shared resources under EBUA. We conduct experimental studies by simulating the algorithm on the DVS-enabled AMD k6 processor model, and by implementing it on QNX Neutrino 6.2.1 RTOS. Our experimental results validate our analytical results. Further, they confirm EBUA's superiority over other energy-efficient real-time scheduling algorithms on timeliness and energy consumption behaviors. / Ph. D.
169

Energieffektivisering av skolor : En studie om energieffektivisering och inneklimat för Rotundaskolan i Västerås

Granlund, Fredric, Nilsson, Alexander, Sundström, Patrik January 2021 (has links)
Purpose: This study aims to see how the total active heating demand and the indoor climate for a school in Vasteras can improve from two different energysaving-investments. The two measures that will be investigated are windows with an improved U-value and an exchange of the ventilation unit with a heat exchanger. The result of the investments will be connected to a value-added study which investigates its impact on social, economy and environmental aspects. Method: To accomplish this, a literature study has been made to gather information to support the calculations and compare our results with previous studies. A case study which consists of calculations, a study visits to the school and a documentation analysis to strengthen the accuracy of the results. Results: The yearly total active heating for the school was 426 MWh with a heat demand of 191 kWh/m2 which is bad compared to equal buildings which normally use between 120-180 kWh/m 2. The exchange of the ventilation unit and the implement of a heat exchanger decreased the yearly active heating demand with 105 MWh which is equal to 144 kWh/m2. This is a much better value and now in the category of equal buildings. By investing in windows with a U-value of 1.3 W/m2 K from 3.0 W/m2 saved the building 29 MWh every year to 178 kWh/m2 which is just under the maximum value of 180 kWh/m 2 . Conclusions: Investing in a new ventilation unit with a heat exchanger showed to be the best investment for the school at this moment in time. The new heat exchanger contributes to a large energy saving and the investment cost had a payback time between 9 - 18 years depending on the kWh price. The study got similar results in the value-added study where the ventilation unit showed a greater impact on almost all of FN: s global goals. Windows did not show as impressive results as the ventilation unit did and is why it contributed less to the global goals in the value-added study.
170

Energieffektivitet hos fönster - Idag och i framtiden : En analys samt komparativ studie av fönster för byggnader, med fokus på aeorgel-, vacuum och smarta-fönster

Tahan, Petrus January 2016 (has links)
Energieffektivisering börjar bli ett eftersträvande mål runtom i världen. Detta grundar sig i att energiförbrukningen för byggnader uppgår till ca 40 % globalt, en siffra som man vill få ner. Men att uppnå en energieffektiv byggnad är inte lätt. Detta kan göras på många och olika sätt. Ett av dem är att energieffektivisera fönstren, som är en byggnads svagaste punkt pga dess höga U-värde. Val av fönster är inte lätt, och det finns ett flertal alternativ att välja bland. I kalla klimat som Sverige söker man fönster med lågt U-värde och högt g-värde, samt en hög avskärmningsfaktor. I varmare länder vill man också ha ett lågt U-värde hos fönster men fokusen ligger främst på en låg avskärmningsfaktor. Syftet med uppsatsen var att hitta de mest energieffektiva fönstren, oavsett kostnad, för byggnader som befinner sig i länder med kallare klimat. Det var också av vikt att få veta lönsamheten för fönstren i fråga, därför har även kostnadsfrågor belysts. Metodvalen var informationssökning i olika databaser och litteratur samt att olika företag inom fönsterbranschen kontaktades, vilket ledde till att relevant och önskvärd information erhölls. Därefter fortskred arbetet genom kalkyleringar för energibalansen och lönsamheten. Vacuumfönster, aerogelfönster samt kromogena fönster hör till framtida fönster som kan tillföra positiva inverkan på energibalansen för byggnader. Men dessa fönster är i nuläget inte helt färdigutvecklade, fast har potential att bli världsledande. Vacuumfönster och kromogena fönster är i nuläget bättre lämpade för varmare klimat. Lyckas man komma längre med deras nutida utveckling är det inte omöjligt att anpassa de för kallare klimat. Aerogelfönster ger mest energibesparing vid byte av fönster, men pga vissa optiska egenskaper och komplicerad tillverkning av produkten är den i nuläget inte optimal vid ett fönsterbyte. De framtida fönstren är ej heller ekonomiskt försvarbara, det finns i dagsläget kommersiella energieffektiva fönster som är billigare att införskaffa och ger ett ansenligt bra resultat för en byggnads energibalans. / Energy optimization is starting to be a pursued worldwide main goal. This is based on the global energy consumption that occurs in buildings, which is about 40 percent. There is no doubt that this value needs to be lowered. But to achieve an energy efficient building is not easy. Although, this can be done in many and different ways. One of them is to optimize the windows, which is a buildings weakest point due to its high U-value.The choice of windows can be a harsh decision, there’s plenty of windows to choose among. In heating dominated climates, as the one in Sweden, it is necessary to choose windows with low U-values and high g-values, also a high solar heat gain coefficient/shading coefficient is required. A window with a low U-value is also important in cooling dominated climates but the main focus is instead on a low shading coefficient, which is not the case in this thesis. The purpose is to find the most energy efficient window that lowers the need for active heating in buildings, and also reveal and discuss the cost issues for the chosen windows.By searching in scientific databases and contacting companies active in the window industry the desired information was obtained. Calculations including the energy balance and present value were made, which gave an indication of the profitability for the different windows. Vacuum, aerogel and chromogenic window are examples of future windows which can have a positive impact on the energy balance in buildings. Yet these windows are currently not fully developed, but have potential to be highly valuable types of windows. Vacuum and chromogenic windows are better suited for cooling dominated climates. However if the development succeed where a big progress will be made it will not be impossible to suit them for heating dominated climates too. Aerogel windows have the best impact on the energy savings when replacing windows, but due to some optical attributes and a complicated manufacturing of the product aerogel windows are currently not an optimal choice for window replacement. The future windows isn’t either economically viable. For now, there are other commercially energy efficient windows that are cheaper to purchase. They also show an acceptable good result on the energy balance for a building.

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