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Apparater, aktiviteter och aktörer : Lågenergiboende som resurs och restriktion för energiordningar / Appliances, activities and actors : Low energy housing - resources and restrictions for energy ordersKarresand, Helena January 2014 (has links)
Energianvändningen inom bostadssektorn har stadigt ökat och verkar inte minska trots energieffektiva apparater. Genom att bygga lågenergibostäder försöker bostadsbolagen minska energianvändningen, vilket också sker, men endast vad gäller uppvärmning och varmvatten. Syfte med avhandlingen är att öka kunskapen kring hushållens energianvändning i passivhus med fokus på hushållens aktiviteter. Intervjustudier har utförts med hushåll och bostadsbolag för att utröna hur de materiella förutsättningarna påverkar vardagsaktiviteter i hushållen. Utifrån tidsgeografiska begrepp analyseras några vardagliga hushållsprojekt: mathållning, klädvård och rekreation. Begreppet energiordning används för att påvisa hur aktiviteters genomförande påverkas av resurser, restriktioner och möjligheter av olika slag, inklusive elektricitet. Eftersom varje hushåll är unikt kommer också energiordningarna i hushållen att se olika ut vilket påverkar värmekomforten i bostaden. Passivhuskonceptet som sådant påverkar inte aktiviteterna i nämnvärd grad, men hushållen bevarar gärna den värme som uppstår i och med olika aktiviteter genom att öppna dörrar och ugnsluckor för att sprida värmen i bostaden. En slutsats från studien är att eftersom alla hushåll har unika energiordningar behöver också de materiella resurserna anpassas så att olika handlingsalternativ blir möjliga. Genom att ta del av hushållens erfarenheter av olika energiordningar kan bostadsbolagen få tillgång till nya idéer och anpassa de materiella förutsättningarna till hushållens behov så att energieffektivt boende också inbegriper hushållens aktiviteter. / Energy use in the residential sector has gradually increased and does not seem to be decreasing in spite of energy efficient appliances. By building low energy homes, housing companies are trying to reduce energy use, and to some extent they are succeeding, although the reductions are confined to heating and hot water. The aim of the thesis is to increase knowledge about household energy use in passive houses focusing on household activities. Interviews were conducted with households and public housing companies to investigate how material conditions, such as the flats and the appliances, affect daily activities in the home. Based on time-geographic concepts, a few everyday household projects are analyzed: cooking, care of clothing and recreation. The concept of energy orders is used to show that the realization of activities is influenced by various kinds of resources, including electricity, and the constraints and opportunities related to them. Since each household is unique, the energy orders also look different, which has an influence on the thermal comfort in the home. The passive house concept as such does not affect household activities in a profound way, but the households try to preserve and spread the spill heat generated in various activities by opening doors to rooms and doors of appliances such as the oven to distribute the heat throughout the flat. One conclusion from the thesis is that, because all households have unique energy orders, material resources also need to be adapted so that activities can be performed in a variety of ways. By taking advantage of household experiences, housing companies may gain access to new ideas and improve functionality so that material conditions suit household needs. By taking advantage of household experiences, housing companies may gain access to new ideas and improve functionality so that material conditions in energy efficient housing are designed to suit a broad range of household needs.
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The use of steady-state level combinations and signal event edge correlations in the disaggregation of total power measurementsPenn, Joseph J January 2015 (has links)
A dissertation submitted to the Faculty of Engineering and the
Built Environment, University of the Witwatersrand,
Johannesburg, in ful lment of the requirements for the degree
of Master of Science in Engineering.
Johannesburg, 2015 / The work presented extends and contributes to research in Non-Intrusive
Load Monitoring (NILM), focussing on steady-state and transient power
measurement disaggregation techniques for circuits containing household ap-
pliances. Although previous work in this area has produced and evaluated a
wide range of NILM approaches, much of it has involved the use of datasets
captured from real-world household implementations. In such cases, the lack
of accurate ground truth data makes it di cult to assess disaggregation tech-
niques. In the research presented, three NILM techniques are comparatively
evaluated using measurements from typical household appliances assembled
within a laboratory environment, where accurate ground truth data could
be compiled to complement the measurements. This allows for the accu-
racy of the various disaggregation approaches to be precisely evaluated. It
is demonstrated that the correlation of transient event edges in aggregated
power measurements to individual appliance transient exemplars performs
better than the matching of steady-state power levels against individual ap-
pliance state combinations. Furthermore, the transient approach is shown to
be the most appropriate technique for further development. / MT2017
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Förbrukningsflexibilitetens potential och påverkan på kraftsystemet : Med fokus på automatisk frekvensreglering genom styrning av kylskåp / The potential of demand response and its impact on the power system : With focus on fridges as automatic frequency control reservesLy, Sandra, Thell, Linda January 2015 (has links)
Increased use of variable energy and integration of electricity markets in the European Union have led to new challenges when balancing supply and demand in the grid. Load management is a possible way to manage these challenges by adjusting electricity consumption in order to balance the power system. Household appliances can be used for this purpose, for example by providing automatic frequency control. The aim of this master thesis is to investigate the potential of load management from private households and to examine how the power system is affected by a more flexible electricity consumption. The thesis focuses on fridges as automatic frequency control reserves and the ability of fridges to balance the power system. Attributes such as capacity, activation time, persistence and the effect of load reconnection has been modelled in Simulink, Matlab. Complementary interviews with actors from the electricity industry have been done to summarize their insights on demand response. The results indicate that fridges can be used as a part of the automatic frequency controlled reserve FCR-N, based on assumptions made in this study. However, current requirements imposed on balancing resources are not fully met by the fridges. In order for household appliances to provide the needed flexibility, some requirements might need to be rephrased. The results also show that the capacity for providing balancing services differs for positive and negative imbalances, as consumption can be reduced with 30 MW and increased with 66 MW. When controlling the fridges by moving the reference temperature, there is a risk that the appliances will synchronize with each other, i.e. reconnect or disconnect at the same time, resulting in frequency oscillations. It is therefore important that load management is designed to avoid this kind of behavior.
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Förbrukningsflexibilitetens potential och påverkan på kraftsystemet : Med fokus på automatisk frekvensreglering genom styrning av kylskåp / The potential of demand response and its impact on the power system, with focus on fridges as automatic frequency control reservesLy, Sandra, Thell, Linda January 2015 (has links)
Increased use of variable energy and integration of electricity markets in the European Union have led to new challenges when balancing supply and demand in the grid. Load management is a possible way to manage these challenges by adjusting electricity consumption in order to balance the power system. Household appliances can be used for this purpose, for example by providing automatic frequency control. The aim of this master thesis is to investigate the potential of load management from private households and to examine how the power system is affected by a more flexible electricity consumption. The thesis focuses on fridges as automatic frequency control reserves and the ability of fridges to balance the power system. Attributes such as capacity, activation time, persistence and the effect of load reconnection has been modelled in Simulink, Matlab. Complementary interviews with actors from the electricity industry have been done to summarize their insights on demand response. The results indicate that fridges can be used as a part of the automatic frequency controlled reserve FCR-N, based on assumptions made in this study. However, current requirements imposed on balancing resources are not fully met by the fridges. In order for household appliances to provide the needed flexibility, some requirements might need to be rephrased. The results also show that the capacity for providing balancing services differs for positive and negative imbalances, as consumption can be reduced with 30 MW and increased with 66 MW. When controlling the fridges by moving the reference temperature, there is a risk that the appliances will synchronize with each other, i.e. reconnect or disconnect at the same time, resulting in frequency oscillations. It is therefore important that load management is designed to avoid this kind of behavior.
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International brand management of Chinese companies : case studies on the Chinese household applicances and consumer electronics industry entering US and Western European markets /Bell, Sandra. January 2008 (has links) (PDF)
Univ., Mercator School of Management, Diss.--Duisburg Essen, 2008.
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Proposition d’un cadre méthodologique comme support aux approches d’écoconception en entreprise : exigences et conceptualisation pour une plateforme logicielle / A methodological framework to support integrated ecodesign for companies : requirements and conceptualization towards a software platformDufrene, Maud 29 April 2015 (has links)
La prise en compte des enjeux environnementaux est aujourd'hui un point essentiel dans la stratégie de développement durable des entreprises. La revue de la littérature montre que l'écoconception n'est pas simple à intégrer du fait de ses spécificités. Malgré le nombre important d'outils et de méthodes existantes, les entreprises rencontrent encore souvent des difficultés à intégrer l'écoconception dans leur processus de conception.Ces recherches proposent donc une solution couplant une méthodologie et une plateforme logicielle. La méthodologie guide l'équipe de conception à travers une série d'étapes à réaliser dans le processus de conception. Et pour gérer les activités d'écoconception, nous avons défini la structure d'une plateforme logicielle rassemblant les outils nécessaires à l'équipe de conception : des outils pour la conception du cycle de vie du produit, un outil d'évaluation des impacts coût et environnement, un outil d'aide à base de règles de conception et d'études de cas, un outil de suivi des indicateurs projet et des bases de données en relation avec le modèle produit et son cycle de vie.Les résultats de deux expérimentations industrielles démontrent la validité de notre proposition. Cependant, une limite de la plateforme a été identifiée lors du second cas d'étude. Une troisième expérimentation a donc été réalisée lors d'un atelier pendant une conférence internationale pour solutionner ce point. / Today the consideration of environmental issues is essential in relation to companies' sustainability policy. The literature review reveals that ecodesign is not an easy viewpoint to integrate due to its specificities. Despite the great number of existing tools and methods, companies still encounter difficulties for implementing ecodesign in their design process.This research work aims at providing a combined solution including a methodology supported by a software platform. The methodology guides the design team through a series of steps to realize in the design process. And, to manage ecodesign activities, we defined the structure of a software platform gathering the necessary tools for the design team: tools for the design of the product life cycle, an assessment tool for the cost and the environmental impacts, a guidance tool based on ecodesign rules and case studies, a monitoring tool for the project indicators, and databases in relation with the model of the product and its life cycle.The results of two industrial experiments demonstrate the validity of our proposition. However, a limit of the platform has been identified during the second case study. A third experiment has therefore been realised during a workshop in an international conference to tackle this point.
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Abordagem sistemática para elaboração da especificação de produtos eletrodomésticosMorosini, Marcel Monteiro 28 October 2013 (has links)
Para que o desenvolvimento de um novo produto tenha melhores chances de sucesso no competitivo mercado atual, as empresas devem preocupar-se em contemplar as reais necessidades dos clientes em seus projetos. Para tanto, é preciso que os desejos dos clientes transformem-se corretamente em especificações de produto claras e objetivas. Caso contrário, as incorretas ou subjetivas especificações-meta podem gerar um produto que não atenda às expectativas do consumidor. Sabe-se que o reprojeto e retrabalho para modificação do produto implicariam em perdas de tempo, custo e qualidade. Por isso, o processo de geração de especificações no desenvolvimento de produtos é crítico para atingir as metas de time-to-market, custo e qualidade do produto final. A tradução da voz do cliente em requisitos técnicos de projeto é, geralmente, realizada através de métodos como, por exemplo, o QFD. Contudo, o QFD não é muito utilizado na prática em diversos tipos de indústrias, como a de eletrodomésticos, devido a sua generalidade e dificuldade de uso. Desta forma, tem-se por objetivo principal desenvolver uma abordagem sistemática para auxiliar a elaboração de especificações-meta de um eletrodoméstico, no caso, um fogão. Foi realizada uma pesquisa de campo em uma empresa do ramo para a verificação da oportunidade de pesquisa e coleta de dados para o desenvolvimento de um método e ferramenta. Em seguida, elaborou-se uma ferramenta em planilha eletrônica na qual as especificações-meta de um fogão são geradas automaticamente a partir das informações de entrada de projeto. A validação da sistemática foi realizada pela análise comparativa do resultado gerado pela ferramenta com produtos anteriores já desenvolvidos pela empresa pesquisada. O resultado deste estudo indicou que o método proposto apresenta-se como um mecanismo para geração de especificações de maneira simples e prática, contribuindo para a maior assertividade no desenvolvimento do produto e possível de ser incorporado ao cotidiano da empresa. / In order for a new product development to have better chances of success in today’s competitive market, companies should focus on meeting the real consumer needs in their projects. Thus, it is necessary that the consumer wishes be transformed correctly into clear and objective product specifications. Otherwise, the incorrect or subjective target specifications could generate a product which does not fulfill to the consumer expectations. It is known that the redesign and rework needed due to product modifications would involve loss of time, cost and quality. So, the specification elaboration process during the product development is critical to achieve the targets as time-to-market, cost and quality of the final product. The translation of the voice of customer into project technical requirements is usually accomplished by such methods as, for example, QFD. However, the QFD is not used very often in several industries, like the home appliances factory, because it is general and difficult to use. Therefore, the main objective is to develop a systematic approach for a home appliance specification elaboration, in this case, a cooker. A field study was conducted in a company of this branch to verify the research opportunity and data collection for the method and tool development. Next, an electronic spreadsheet toll was developed for automatically generate the target specifications of a cooker from input data of the project. The systematic validation was implemented by the comparative analysis among the results obtained by the tool with previous products already developed by the researched company. The result of this study indicates that the method proposed is a mechanism for generating specifications in a simple and practical way, contributing to greater assertiveness in product development and can be embedded in the daily-basis process of the company.
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Abordagem sistemática para elaboração da especificação de produtos eletrodomésticosMorosini, Marcel Monteiro 28 October 2013 (has links)
Para que o desenvolvimento de um novo produto tenha melhores chances de sucesso no competitivo mercado atual, as empresas devem preocupar-se em contemplar as reais necessidades dos clientes em seus projetos. Para tanto, é preciso que os desejos dos clientes transformem-se corretamente em especificações de produto claras e objetivas. Caso contrário, as incorretas ou subjetivas especificações-meta podem gerar um produto que não atenda às expectativas do consumidor. Sabe-se que o reprojeto e retrabalho para modificação do produto implicariam em perdas de tempo, custo e qualidade. Por isso, o processo de geração de especificações no desenvolvimento de produtos é crítico para atingir as metas de time-to-market, custo e qualidade do produto final. A tradução da voz do cliente em requisitos técnicos de projeto é, geralmente, realizada através de métodos como, por exemplo, o QFD. Contudo, o QFD não é muito utilizado na prática em diversos tipos de indústrias, como a de eletrodomésticos, devido a sua generalidade e dificuldade de uso. Desta forma, tem-se por objetivo principal desenvolver uma abordagem sistemática para auxiliar a elaboração de especificações-meta de um eletrodoméstico, no caso, um fogão. Foi realizada uma pesquisa de campo em uma empresa do ramo para a verificação da oportunidade de pesquisa e coleta de dados para o desenvolvimento de um método e ferramenta. Em seguida, elaborou-se uma ferramenta em planilha eletrônica na qual as especificações-meta de um fogão são geradas automaticamente a partir das informações de entrada de projeto. A validação da sistemática foi realizada pela análise comparativa do resultado gerado pela ferramenta com produtos anteriores já desenvolvidos pela empresa pesquisada. O resultado deste estudo indicou que o método proposto apresenta-se como um mecanismo para geração de especificações de maneira simples e prática, contribuindo para a maior assertividade no desenvolvimento do produto e possível de ser incorporado ao cotidiano da empresa. / In order for a new product development to have better chances of success in today’s competitive market, companies should focus on meeting the real consumer needs in their projects. Thus, it is necessary that the consumer wishes be transformed correctly into clear and objective product specifications. Otherwise, the incorrect or subjective target specifications could generate a product which does not fulfill to the consumer expectations. It is known that the redesign and rework needed due to product modifications would involve loss of time, cost and quality. So, the specification elaboration process during the product development is critical to achieve the targets as time-to-market, cost and quality of the final product. The translation of the voice of customer into project technical requirements is usually accomplished by such methods as, for example, QFD. However, the QFD is not used very often in several industries, like the home appliances factory, because it is general and difficult to use. Therefore, the main objective is to develop a systematic approach for a home appliance specification elaboration, in this case, a cooker. A field study was conducted in a company of this branch to verify the research opportunity and data collection for the method and tool development. Next, an electronic spreadsheet toll was developed for automatically generate the target specifications of a cooker from input data of the project. The systematic validation was implemented by the comparative analysis among the results obtained by the tool with previous products already developed by the researched company. The result of this study indicates that the method proposed is a mechanism for generating specifications in a simple and practical way, contributing to greater assertiveness in product development and can be embedded in the daily-basis process of the company.
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Experimental investigation of a heat pump tumble dryer with a zeotropic refrigerant mixtureCop, Melanie, Barta, Riley B., Thomas, Christiane, Hesse, Ullrich 27 November 2024 (has links)
Due to their high global warming potential (GWP), fluorinated refrigerants are being replaced in many heat pump and refrigeration systems. Especially in small systems such as heat pump tumble dryers (HPTD), the replacement of the globally used working fluid in this application, R134a, appears to be manageable. One established alternative is the use of hydrocarbon refrigerants. Within this research project, new zeotropic refrigerant blends of hydrocarbons are theoretically evaluated as retrofit substitutes for R134a in heat pump tumble dryers. The aim is to use the temperature glide inherent to zeotropic mixtures during phase change to increase the heat transfer efficiency and thus, the COP of the system. A mixture of R290 (propane) and RE170 (dimethyl ether) was selected and experimentally investigated in a commercially available HPTD. To assess the new mixture, parameters relevant to the cycle such as pressure, temperature, compressor power, and the dryer moisture extraction rate are compared to those values achieved using the refrigerant R134a. Retaining the heat exchanger and compressor from the R134a system, the system charge with the new mixture was 40 % lower, while the thermal capacity was equal to or higher than that of the R134a system. The increased temperature level supplied by the mixture reduced the drying time and the energy consumption of the HPTD. The investigation showed that the heat exchanger design needed to be adapted to the temperature glide properties of the mixture in order to realize meaningful heat transfer efficiency gains.
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