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Multimodal sensing for robust and energy-efficient context detection with smart mobile devicesRadu, Valentin January 2017 (has links)
Adoption of smart mobile devices (smartphones, wearables, etc.) is rapidly growing. There are already over 2 billion smartphone users worldwide [1] and the percentage of smartphone users is expected to be over 50% in the next five years [2]. These devices feature rich sensing capabilities which allow inferences about mobile device user’s surroundings and behavior. Multiple and diverse sensors common on such mobile devices facilitate observing the environment from different perspectives, which helps to increase robustness of inferences and enables more complex context detection tasks. Though a larger number of sensing modalities can be beneficial for more accurate and wider mobile context detection, integrating these sensor streams is non-trivial. This thesis presents how multimodal sensor data can be integrated to facilitate ro- bust and energy efficient mobile context detection, considering three important and challenging detection tasks: indoor localization, indoor-outdoor detection and human activity recognition. This thesis presents three methods for multimodal sensor inte- gration, each applied for a different type of context detection task considered in this thesis. These are gradually decreasing in design complexity, starting with a solution based on an engineering approach decomposing context detection to simpler tasks and integrating these with a particle filter for indoor localization. This is followed by man- ual extraction of features from different sensors and using an adaptive machine learn- ing technique called semi-supervised learning for indoor-outdoor detection. Finally, a method using deep neural networks capable of extracting non-intuitive features di- rectly from raw sensor data is used for human activity recognition; this method also provides higher degree of generalization to other context detection tasks. Energy efficiency is an important consideration in general for battery powered mo- bile devices and context detection is no exception. In the various context detection tasks and solutions presented in this thesis, particular attention is paid to this issue by relying largely on sensors that consume low energy and on lightweight computations. Overall, the solutions presented improve on the state of the art in terms of accuracy and robustness while keeping the energy consumption low, making them practical for use on mobile devices.
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Análise da eficiência energética e da viabilidade dos ciclos de absorção na frigorificação de cargas / Analysis of energy efficiency and viability of the absorption refrigeration cycle loadAri Ferreira de Abreu 06 July 1994 (has links)
Este trabalho aborda a problemática do transporte de carga frigorificada, sob a ótica da eficiência energética da unidade frigorífica. São propostas alternativas para conservação de alimentos, independentemente do frio. Embora incapazes de substituir totalmente o frio, podem ser uma alternativa em vários casos. É analisada a tecnologia de frigorificação atualmente empregada, enfocando custos do sistema, eficiência energética e efeitos da atual tecnologia sobre o meio ambiente. É desenvolvido o projeto preliminar de uma unidade de refrigeração por absorção, que é analisado comparativamente com as unidades por compressão a vapor. Este estudo mostra que o sistema de refrigeração por absorção pode ser viável em muitas aplicações onde não se dispõe de energia térmica ou mecânica. / This study analyses refrigerated freigth transportation, under the scope of refrigeration energy effeciency. There are several alternatives for food conservation, independently of refrigeration. These existing technologies are not capable of completely replacing refrigeration, but they could be utilized in many cases. The refrigeration techonology currently used is analysed, focusing on system costs, energy efficiency and environmental impacts. A preliminary design of an absoption system was done and an analysis was performed comparating it with the compression units. Conclusive analysis of the system will depend of the evaluation of the experimental unit. This study shows that refrigeration by absortion could be viable in various aplications where no electricity or mechanical energy are available.
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Condições Operacionais para o Desenvolvimento do Mercado de Eficiência Energética no Setor Residencial: O Caso de Cochabamba, Bolívia / Operating Conditions for the Development of Market Efficiency in the Residential Sector: The Case of Cochabamba, BoliviaJorge Marcial Choque Ajhuacho 09 December 1998 (has links)
A próxima década oferece ao mundo um verdadeiro desafio em relação à conservação de várias formas de energia. Para isso, torna-se necessário a cooperação de vários agentes envolvidos no desenvolvimento de um mercado de eficiência energética, tais como, o governo, a agência reguladora, as empresas geradoras de eletricidade, os vendedores de equipamentos, as empresas distribuidoras de eletricidade e os consumidores. O setor residencial da cidade de Cochabamba é responsável por 44% do consumo de energia elétrica, abrange 86.88% dos consumidores do sistema elétrico de Cochabamba e tem uma taxa média de crescimento da demanda de energia elétrica de 8.S% ao ano. Este setor é muito importante e apresenta um grande potencial de conservação de energia elétrica nos três usos finais que apresentam o maior consumo (79%) em Cochabamba: refrigeração, iluminação e aquecimento da água. No presente trabalho, realiza-se a caracterização da demanda de eletricidade por usos finais em um estudo-piloto, com uma metodologia desenvolvida a partir da realização de uma pesquisa de hábitos de consumo e posse de eletrodomésticos. São analisadas as oportunidades que apresentam-se atualmente na Bolívia para viabilizar o desenvolvimento do mercado de tecnologia ecientes em razão da recente restruturação do setor elétrico boliviano que oferece sinais econômicos de mercado para atingir a eficiência econômica no fornecimento elétrico a custo mínimo. Também são analisadas as barreiras que existem na Bolívia para a introdução de tecnologias eficientes no mercado e propõem-se diversas condições que devem estabelecer-se para desenvolver um mercado de eciência energética. Analisam-se as condições operacionais associando ações do agente regulador, dos vendedores de equipamentos das empresas de energia elétrica e dos consumidores para a aceleração da penetração de tecnologias eficientes de uso final disponíveis em outros mercados. / The next decade introduces a real challenge for energy conservation. This will require the cooperation of many actors involved in an energy efficiency market as the government, the regulatory body, the electric power generating companies, the equipment vendors, the electricity distribution companies and the consumers. In the city of Cochabamba, the residential sector uses 44 percent of the total electrical energy consumption and corresponds to 86,88 percent of the electricity users. As the average demand growth rate is 8.5 percent per year, the residential sector has a large potential for electricity conservation because the three most important end-uses (lighting, refrigeration and water heating) consume 79 percent of total electricity in Cochabamba. The present work assesses the electricity end-uses through a pilot study, applying a methodology using a survey on electrical appliances and consumption. The opportunities for development of an energy efficient tecnologies market in Bolivia are also analized as the recent electricy reform is providing economic signals to achieve economic efficiency at the least-cost electricity supply. The barriers to the introduction of energy efficient tecnologies in Bolivia are also considered with the required conditions for development of a market for energy efficiency. For that purpose, the operational conditions includes the role of the regulatory agency, the equipment vendors, the electricity companies and the consumers in order to accelerate the introduction of efficient tecnologies for end uses available in other markets.
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Automated glazed facades : occupant responses and architects rationalesStevens, Sarah January 1999 (has links)
No description available.
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Energy Efficiency Opportunities in a Pulp Drying MachineMohey, Gagandeep January 2016 (has links)
Global concerns about declining resources and climate change mean that industries must do their best to use energy as efficiently as possible. Energy is also an important component of a modern economy. The pulp and paper industry is one of the most energy-intensive industries round the world. In this study energy efficiency opportunities in pulp drying machines are identified and the saving potential is then quantified. The methodology followed was based on comparison of energy saving technologies and practices such as Turbo Vacuum blowers, Shoe Press, Heat pump, Use of low pressure steam etc. The data used for the calculations was taken from the mill data records. Six energy efficiency improvement projects were identified. The total proposed energy saving potential in the two Drying Machines studied in the thesis is 10511 MWh. Installation of the shoe press shows the highest saving potential followed by the turbo vacuum blowers. Although the accuracy of the results is heavily dependent upon the accuracy of the data records from the case study mill. The proposed savings would act as a reference point and depending upon the estimated savings potential, would help the mill to identify areas, projects that need more detailed measurements for further action.
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Evaluation of a high-rise building for passive house classifications in PHPP : Simulation and optimization of energy efficiency measures for residential high-rise buildings in different climatesLundberg, Nils January 2016 (has links)
This thesis is a part of the major EU project EE-Highrise which is a part of the European 7th Framework Research Program (FP7-ENERGY). In order to demonstrate and test new technologies and concepts, a demo building has been constructed in Ljubljana, the capital of Slovenia. The approach during the development of the building has been to consider all its elements with the purpose to increase the energy efficiency and sustainability of the building. Umeå University’s objective is to develop regional specific models of the demo high-rise building. The objective of this thesis is to evaluate whether a simplified model of the high rise building, Eco Silver House, can meet the passive house classifications in four selected cities; Ljubljana, Sibenik, Umeå and Dubai and then to suggest improvements of the models for the different regions. Drawings of the building were provided along with an IFC file for construction of the model in PHPP. The simulation tool used for simulations, PHPP, contained all necessary tools for designing a properly functioning Passive House. By preparing an energy balance, the annual energy demand of the building was calculated based on input related to building characteristics. Results from the simulations have then been compared to the requirements for the German Passive House classification. The performance of the building in Umeå has also be compared to the Swedish passive house standards. Improvements to the climate shell and the ventilation system were after that examined depending on the results. It was shown that it is possible to construct regional specific models that fulfill the passive house requirements in three of four regions. The model achieved passive house standard without any additional energy efficiency measures in Ljubljana and Šibenik while a combination of measures was needed to fulfill all the criteria’s in Umeå. The Swedish requirements used for evaluation of the model in Sweden were easier to fulfill since they have been developed for the cold climate present in Umeå. Since no regional passive house classification was used to evaluate the performance of the model in Dubai the cooling and primary energy demand exceeded the limiting criteria’s. The energy efficiency measure with reduced window area had the greatest impact on heating and cooling demand in all climates. This measure should be included in all future models which also is suggested by parallel studies on similar models of the same building. The only climate where an increased U-value of the external envelope resulted in improved performance of the model was in Šibenik. For all the other climates where a lowered U-value was implemented did the overall performance improve. / EE-Highrise (European 7th Framework Research Program.
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Improving the performance of a wind energy systemEchenique Subiabre, Estanislao Juan Pablo January 2015 (has links)
Small and Medium size Wind Turbines (SMWTs) can be used for the production of electricity in residential areas, or integrated into hybrid systems, which makes them more attractive in remote areas with difficult access to electricity from the grid. However, many of the SMWTs are installed in locations with low wind speeds, reducing remarkably their annual energy output. Furthermore, SMWTs are typically operated in sub-optimal conditions because they are not completely understood in the real environment. In a design stage, typically a wind tunnel is used to determine the aerodynamic efficiency, but latest research suggests that a turbine in the field behaves differently, especially when the wind is unsteady. Therefore, the aerodynamic performance of a wind turbine tends to be different in the field. Unfortunately, field testing is expensive, and requires long term measurements, especially for small turbine manufacturers. This thesis investigates four topics that could greatly impact the performance of a wind turbine: 1. the wind resource, and how by the spectral modelling of its unsteadiness it is possible to design better turbines and control systems, to adequately react in gusty wind conditions in order to maximise energy harvesting; 2. resource assessment using short-term measurements of wind, to reduce the uncertainty in annual energy production; 3. loss modelling in the generator and power converter to optimise overall efficiency of a wind energy conversion system; and 4. aerodynamic performance identification based on field measurements. On each of these fields, new methods are proposed and validated to improve the existing knowledge. Regarding loss modelling and optimisation, an algorithm to find the global optimum in a system with losses is proposed and tested in an 800 W vertical-axis wind turbine owned by Airborne- Energy Ltd. The experimental data collected in the field, confirms the validity of the approach and its ability to find the optimum despite the high inertia of the turbine, and the unsteadiness of the wind. It is shown that a control algorithm that seeks a global optimum, can increase the overall efficiency of the system, and reduces internal stress on the shaft and power electronics. Finally, as the optimisation algorithm developed in this thesis features the estimation of parameters for a turbine, the processed information can have two positive impacts for further study: detection of system faults and diagnostic of the health-state of the system; and, design specifications, as the manufacturer can have direct inputs of the performance of the turbine to make further improvements for new designs.
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Environmental technologies and reshaping of healthcare architectureChaturvedi, Surabhi January 2009 (has links)
This research investigates adoption and integration of a range of building environmental systems in healthcare facilities in India. Based on detailed case studies of eight selected healthcare facilities developed at different times in India, this research traces the evolution of hospital designs in a specific geographic context through the lens of adoption of building environmental systems over the internal shell and external skins of healthcare buildings in India. By documenting and analyzing changes in building designs over time, the research develops a comparative understanding of trends of adoption of environmental technologies and their impacts on building form and performance.
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Combining simulation and optimization for improved decision support on energy efficiency in industryMardan, Nawzad January 2012 (has links)
Industrial production systems in general are very complex and there is a need for decision support regarding management of the daily production as well as regarding investments to increase energy efficiency and to decrease environmental effects and overall costs. Simulation of industrial production as well as energy systems optimization may be used in such complex decision-making situations. The simulation tool is most powerful when used for design and analysis of complex production processes. This tool can give very detailed information about how the system operates, for example, information about the disturbances that occur in the system, such as lack of raw materials, blockages or stoppages on a production line. Furthermore, it can also be used to identify bottlenecks to indicate where work in process, material, and information are being delayed. The energy systems optimization tool can provide the company management additional information for the type of investment studied. The tool is able to obtain more basic data for decision-making and thus also additional information for the production-related investment being studied. The use of the energy systems optimization tool as investment decision support when considering strategic investments for an industry with complex interactions between different production units seems greatly needed. If not adopted and used, the industry may face a risk of costly reinvestments. Although these decision-making tools individually give good results, the possibility to use them in combination increases the reliability of the results, enhances the possibility to find optimal solutions, promises improved analyses, and a better basis for decisions in industry. The energy systems optimization tool can be used to find the optimal result and the simulation tool can be used to find out whether the solution from the optimization tool is possible to run at the site. In this thesis, the discrete event simulation and energy systems optimization tools have been combined. Three Swedish industrial case studies are included: The new foundry at Volvo Powertrain in Skövde, Arla Foods dairy in Linköping and the SKF foundry in Katrineholm. Results from these cases show possibilities to decrease energy use and idling, to increase production, to combine existing and new production equipment and to decrease loss of products. For an existing industrial system, it is always preferable to start with the optimization tool reMIND rather than the simulation tool – since it takes less time to build the optimization model and obtain results than it does to build the corresponding simulation modeling. While, for a non-existent system, it is in general a good idea to use both the simulation and the optimization tool reMIND simultaneously, because there are many uncertain data that are difficult to estimate, by using only one of them. An iterative working process may follow where both tools are used. There is a need for future work to further develop structured working processes and to improve the model to e.g. take production related support processes into account. To adapt the results in industries, improve the user friendliness of the tool and the understanding of the underlying modeling developments of the optimization tool reMIND will be necessary. / Industriella system i allmänhet är mycket komplexa och det finns ett behov av beslutsstöd vid hantering av den dagliga produktionen, liksom beslut om investeringar för att öka energieffektiviteten och minska miljöpåverkan och kostnader. Simulering av industriell produktion och energisystemoptimering kan användas som beslutsstöd i sådana komplexa beslutssituationer. Simuleringsverktyg är mest kraftfullt när det används för design och analys av komplexa produktionsprocesser. Verktyget kan ge mycket detaljerad information om hur systemet fungerar, till exempel information om de störningar som inträffar i systemet såsom brist på råvaror, blockeringar eller avbrott på en produktionslinje. Dessutom kan verktyget användas för att identifiera flaskhalsar för att indikera var arbete, material och information är försenade. Energisystemoptimeringsverktyget kan ge företagsledningen ytterligare information om en eventuell studerad investering. Verktyget kan ge mer underlag för att fatta beslut och därmed ge mer information för den produktionsrelaterade investeringen som studeras. Behovet av användningen av energisystemoptimeringsverktyg som investeringsbeslutsstöd när man överväger strategiska investeringar för en industri med komplexa interaktioner mellan olika produktionsenheter bedöms vara stort. Om inte kan industrin istället möta en risk för kostsamma reinvesteringar. Även om dessa verktyg kan vara beslutsstöd var för sig och ge bra resultat, så medföljer möjligheten att kombinera dessa verktyg att tillförlitligheten av resultaten ökar, såväl som möjligheten att hitta optimala lösningar, bättre analyser och ett bättre underlag för beslut inom industrin. Optimeringsverktyget kan användas för att hitta det optimala resultatet och simuleringsverktyg kan användas för att ta reda på om lösningen från optimeringsverktyget är möjlig att realisera i verklig drift. I den här avhandlingen har diskret händelsestyrd simulering och energisystemoptimeringsverktyg kombinerats. Tre svenska industriella fallstudier är inkluderade: Volvo Powertrains nya gjuteri i Skövde, Arla Foods mejeri i Linköping och SKF-gjuteriet i Katrineholm. Resultat från dessa fall visar på möjligheterna att minska energianvändningen och tomgångsförlusterna, att öka produktionen, att kombinera ny och befintlig produktionsutrustning på ett effektivare sätt, och att minska kassation av produkter. För ett befintligt industriellt system är det alltid mer effektivt att börja med optimeringsverktyget reMIND snarare än simuleringsverktyg - eftersom det tar mindre tid att bygga en optimeringsmodell och få resultat, än det gör för att bygga en motsvarande simuleringsmodell. För ett icke-existerande system är det i allmänhet ett effektivare tillvägagångssätt att använda både simulerings och optimeringsverktyg reMIND samtidigt, eftersom det finns många osäkra data som är svåra att uppskatta, med hjälp av endast ett av verktygen. En iterativ arbetsprocess kan följa där båda verktyg används. Det finns ett behov av fortsatt arbete bl. a. av att utveckla strukturerade arbetssätt och att kunna integrera produktionsrelaterade stödprocesser i modelleringen. För att anpassa resultaten för industrin, och förbättra användarvänligheten av verktyget, utvecklingen av optimeringsverktyget reMIND kommer att behövas.
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Energieffektivisering av arbetsbodar på byggarbetsplatser / Improvement of the energy efficiency of building shed establishmentsOlsson, Andreas January 2012 (has links)
Everyone has to take a greater responsibility in energy issues, both individuals and companies. There have been some major developments in the construction industry but there is still a lot to be done. This diploma work thesis presents different methods of making existing construction shed establishments to use less energy. What is possible to do and how much energy is there to be saved? A shed establishment consisting of 8 shed units were studied in this project and the building simulation tool VIP-Energy was used to simulate different types of material in the sheds. An infrared camera was used to locate thermal bridges. There are several factors that can be improved to make a construction shed establishment to use less energy. Replacement of old windows and doors, using more insulation, replacement of old less efficient insulation with new improved materials, using a different heating system, and more. One factor, which is more important than all the others, is to insulate between the 8 different shed units in the establishment. It is also important to make the construction wind proof. The results show that if you replace the old wall and roof insulation with new better insulation, replace the old windows and doors and seal the gaps between the shed units the total energy reduction would be as high as 60%. All companies working with the handling or utilization of shed establishments at building sites should consider these improvements.
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