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Lågenergihus : Att bygga energisnåltKarlsson, Camilla January 2010 (has links)
<p>A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms.</p><p><strong> </strong></p><p>Calculations have been done to link the concepts of U<sub>mean</sub> of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis.</p><p> </p><p>The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.<strong></strong></p>
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Optimal And Implementable Transmission Schemes For Energy Harvesting NetworksOzcelik, Fatih Mehmet 01 September 2012 (has links) (PDF)
Progress in energy harvesting technology and the increasing need for the energy efficient and environmentally friendly applications have called for reconsideration of communication systems. This reconsideration results in new problem formulations regarding the recent developments on energy harvesting systems. Recently, optimal strategies for various types of energy harvesting networks have been developed based on different harvesting models. This thesis reports the results of our research to develop the optimal scheduling structures on an energy harvesting broadcast and fading channels, and to devise online implementable algorithms for a
point-to-point communication system. Particularly, structural properties of an optimal offline schedule in, (1) an energy harvesting broadcast channel with one transmitter two receivers, (2) a single user communication system under fading conditions, are investigated. Moreover, an online algorithm is proposed for a single-user energy harvesting communication system considering the physical constraints and necessities regarding implementation. The proposed scheme is implemented through GNU Radio framework on a USRP device.
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Towards a Sustainable Future: Courtyard in Contemporary BeijingZhu, Ningxin January 2013 (has links)
China has become one of the world’s economic engines. One major driving force is the rapid urbanization. Such fast development results in resource and energy depletion, pollution and environmental deterioration. The government has recently endorsed green buildings and urged ministries to work out a national action plan. It is predicted that green building will be the next big thing in China. But before importing any foreign green technology and green designs, is there something to be learned from the Chinese ancestors?
In the long history of China, the Chinese have always employed a system of construction with the influences of geography, climate, culture, philosophy, economy and politics deeply rooted in China, making the Chinese traditional architecture distinct. Embedded in the formation of the city, siheyuan 四合院, the courtyard house in Beijing was one exceptional dwelling example that inherited the quintessence of the thousand years of building experiences and knowledge of the ancestors. This traditional urban type not only celebrated the rich and unique cultural heritage of China, it also played an important role in maximizing the natural forces to create a pleasant and comfortable environment for living. Population growth, political and economic reforms over time however have drastically changed the fate of this historical heritage. Especially under the pressure of the fast development and economic boom after the introduction of the Open Door Policy in 1978, the traditional courtyards were the first to be demolished due to the lack of modern facilities and the inability to accommodate the growing population. They were often replaced by apartment blocks and high-rise towers – imported types based on planning regulations developed in the West, outside the cultural and environmental milieu of Beijing. As a result, the city is now filled with many energy intensive buildings that eat away both the “city’s essence” and the valuable natural resources.
With the current policy and ambition of China, the teardown courtyard sites within the old city wall that are still waiting for development offer the potential to address the remediation and reinterpretation of the traditional typology in a contemporary city. The thesis investigates the essences of the traditional courtyard house and explores the way to apply such qualities to the design of a new courtyard typology in contemporary Beijing. The proposal anticipates a holistic approach on both environmental, social, cultural and economic level, so as to carry out preservation that manifests in experience rather than physical restoration, and to create a project that is truly sustainable.
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Power- and Performance - Aware ArchitecturesCanal Corretger, Ramon 14 June 2004 (has links)
The scaling of silicon technology has been ongoing for over forty years. We are on the way to commercializing devices having a minimum feature size of one-tenth of a micron. The push for miniaturization comes from the demand for higher functionality and higher performance at a lower cost. As a result, successively higher levels of integration have been driving up the power consumption of chips. Today, heat removal and power distribution are at the forefront of the problems faced by chip designers.In recent years portability has become important. Historically, portable applications were characterized by low throughput requirements such as for a wristwatch. This is no longer true.Among the new portable applications are hand-held multimedia terminals with video display and capture, audio reproduction and capture, voice recognition, and handwriting recognition capabilities. These capabilities call for a tremendous amount of computational capacity. This computational capacity has to be realized with very low power requirements in order for the battery to have a satisfactory life span. This thesis is an attempt to provide microarchitecture and compiler techniques for low-power chips with high-computational capacity.The first part of this work presents some schemes for reducing the complexity of the issue logic. The issue logic has become one of the main sources of energy consumption in recent years. The inherent associative look-up and the size of the structures (crucial for exploiting ILP), have led the issue logic to a significant energy budget. The techniques presented in this work eliminate or reduce the associative logic by determining producer-consumer relationships between the instructions or by scheduling the instructions according to the latency of the operations.An important effort has been deployed to reduce the energy requirements and the power dissipation through novel mechanisms based on value compression. As a result, the second part of this thesis introduces several ultra-low power and high-end processor designs. First, the design space for ultra-low power processors is explored. Several designs are developed (at the architectural level) from scratch that exploit value compression at all levels of the data-path. Second, value compression for high-performance processors is proposed and evaluated. At the end of this thesis, two compile-time techniques are presented that show how the compiler can help in reducing the energy consumption. By means of a static analysis of the program code or through profiling, the compiler is able to know the size of the operands involved in the computation. Through these analyses, the compiler is able to use narrower operations (i.e. a 64-bit addition can be converted to an 8-bit addition due to the information of the size of the operands).Overall, this thesis compromises the detailed study of one of the most power hungry units in a processor (the issue logic) and the use of value compression (through hardware and software) as a mean to reduce the energy consumption in all the stages of the pipeline.
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A Scalable, Secure, and Energy-Efficient Image Representation for Wireless SystemsWoo, Tim January 2004 (has links)
The recent growth in wireless communications presents a new challenge to multimedia communications. Digital image transmission is a very common form of multimedia communication. Due to limited bandwidth and broadcast nature of the wireless medium, it is necessary to compress and encrypt images before they are sent. On the other hand, it is important to efficiently utilize the limited energy in wireless devices. In a wireless device, two major sources of energy consumption are energy used for computation and energy used for transmission. Computation energy can be reduced by minimizing the time spent on compression and encryption. Transmission energy can be reduced by sending a smaller image file that is obtained by compressing the original highest quality image. Image quality is often sacrificed in the compression process. Therefore, users should have the flexibility to control the image quality to determine whether such a tradeoff is acceptable. It is also desirable for users to have control over image quality in different areas of the image so that less important areas can be compressed more, while retaining the details in important areas. To reduce computations for encryption, a partial encryption scheme can be employed to encrypt only the critical parts of an image file, without sacrificing security. This thesis proposes a scalable and secure image representation scheme that allows users to select different image quality and security levels. The binary space partitioning (BSP) tree presentation is selected because this representation allows convenient compression and scalable encryption. The Advanced Encryption Standard (AES) is chosen as the encryption algorithm because it is fast and secure. Our experimental result shows that our new tree construction method and our pruning formula reduces execution time, hence computation energy, by about 90%. Our image quality prediction model accurately predicts image quality to within 2-3dB of the actual image PSNR.
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Lågenergihus : Att bygga energisnåltKarlsson, Camilla January 2010 (has links)
A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms. Calculations have been done to link the concepts of Umean of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis. The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.
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Passivhusen på OxtorgetBrandt, Fredrik, Jonsson, Mathilda January 2008 (has links)
Syftet med vårt examensarbete är att undersöka hur passivhus eller så kallade nollenergihus skiljer sig i funktion samt uppbyggnad från konventionella hus. I vår undersökning tar vi upp hur utformning, orientering, material samt ett väl fungerande klimatskal påverkar energiförbrukningen. Vi har tittat närmare på faktorer som sparar energi samt hur ett typiskt passivhus är uppbyggt. För att se hur teorin fungerar i praktiken har vi tittat närmare på befintliga passivhus, nämligen de på Oxtorget i Värnamo. Vi har kommit fram till att passivhus fungerar och vi anser det som väldigt viktigt att man fortsätter driva fram arbetet och informera om dess betydelse för miljön. Passivhus blir mer och mer uppmärksammat. De är något dyrare att bygga, men man tjänar in det i längden. Lönsamheten är dock inte det viktigaste utan känslan av att man gör något bra för miljön. / The main purpose with our diploma work is to examine how passive houses or so called zero energy houses differ in function and construction compared to conventional houses. In our research we present different things such design, orientation, materials and how a fully functional climate shell affects the energy consumption. We’ve looked closer at some factors that save energy and how a typical passive house is constructed. To see how theory works in practice we have looked at existing passive houses, and that is the passive houses on Oxtorget in Värnamo. We have come to the conclusion that the passive houses works and we believe that it is very important that we continues to carry on the work and inform people about its importance to the environment. Passive houses are becoming more and more noticed. They are somewhat more expensive to build but in time you will earn the money spent back. The profit is not the most important but the feeling that you do something good for the environment.
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Solel och solvärme ur LCC-perspektiv för ett passiv-flerbostadshus / PV and solar thermal for a multiple dwelling passive house under a LCC-perspectiveBöhme Florén, Simon January 2008 (has links)
This master’s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance. The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST. Solar thermal systems were calculated by hand and with the software Winsun Villa Education. Both softwares use hourly weather data for the calculations. The LCCs are lower for the two reference alternatives than for the solar energy alternatives. The reference alternative with district heating generates the lowest LCC. The alternatives with solar thermal energy replace more energy and have significantly lower LCCs than the PV alternatives. The study also shows the importance of using cheap and environmentally friendly backup energy for producing DHW. When aiming for a quantitative energy use target, the DHW-circulation losses ought to be taken into account as these can be extensive.
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Housing projekt Pattaya ThailandLindberg, Karin, Nordlander, Anna January 2006 (has links)
This report will examine the problems and possibilities of building a luxurious modern residence in Pattaya, Thailand, incorporating the old traditional building styles of the wooden houses to an ecological house with a low demand for technology. The client, B. Grimm Group, has recently set up a polo club in the vicinity of Pattaya and has requested a complete set of layouts regarding a planned housing area on the premises. The project includes a structure plan of the village area, perspectives, facades, building layouts and axonometric views of all house types, as well as garden plans. The written report works as a complement to the designs and explains the background to the final proposal. The report also handles the building technology and construction process of building a traditional Thai house and briefly investigates the ecological aspects of building in Thailand.
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A Scalable, Secure, and Energy-Efficient Image Representation for Wireless SystemsWoo, Tim January 2004 (has links)
The recent growth in wireless communications presents a new challenge to multimedia communications. Digital image transmission is a very common form of multimedia communication. Due to limited bandwidth and broadcast nature of the wireless medium, it is necessary to compress and encrypt images before they are sent. On the other hand, it is important to efficiently utilize the limited energy in wireless devices. In a wireless device, two major sources of energy consumption are energy used for computation and energy used for transmission. Computation energy can be reduced by minimizing the time spent on compression and encryption. Transmission energy can be reduced by sending a smaller image file that is obtained by compressing the original highest quality image. Image quality is often sacrificed in the compression process. Therefore, users should have the flexibility to control the image quality to determine whether such a tradeoff is acceptable. It is also desirable for users to have control over image quality in different areas of the image so that less important areas can be compressed more, while retaining the details in important areas. To reduce computations for encryption, a partial encryption scheme can be employed to encrypt only the critical parts of an image file, without sacrificing security. This thesis proposes a scalable and secure image representation scheme that allows users to select different image quality and security levels. The binary space partitioning (BSP) tree presentation is selected because this representation allows convenient compression and scalable encryption. The Advanced Encryption Standard (AES) is chosen as the encryption algorithm because it is fast and secure. Our experimental result shows that our new tree construction method and our pruning formula reduces execution time, hence computation energy, by about 90%. Our image quality prediction model accurately predicts image quality to within 2-3dB of the actual image PSNR.
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