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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.
11

Toward Industrialized Retrofitting : Accelerating the Transformation of the Residential Building Stock in Sweden

Wang, Qian January 2013 (has links)
Energy utilization issues are becoming increasingly important around the world. Existing residential and building service sectors represent a large part of total energy utilization, and the corresponding operational costs and environmental impacts are high. Retrofitting is considered an effective way to accelerate the sustainable transformation of the existing building stock. In Sweden, 1945–1975 was a boom period for the construction of residential buildings. After 40–70 years of use, large contingents of buildings need to be systematically retrofitted. In the past, most Swedish buildings were retrofitted individually, and occasionally in small clusters. Cost-effective retrofitting for large-scale implementation has not yet been substantially attained. Standardizing and industrializing the retrofitting process is expected to produce the following benefits: availability of standardized toolkits based on building typologies; simplified and more efficient decision-making process; lower retrofitting costs; shorter project durations; greater resource-efficiency; lower environmental impact; and higher profitability.The overall aim of the present study is to contribute to the knowledge regarding industrialized retrofitting toolkits in Swedish residential buildings and evaluate the various toolkits. More specifically, the study aims to analyze the energy demand saving potential of different retrofitting measures and long-term profits based on the typology of residential buildings. Based on a systematic set of building properties and classification of existing residential types in Sweden, four slab houses (lamellhus) were selected as the major sub-types of building stock for the demonstration cases. The case buildings were constructed between 1945 and 1975 and are currently used as single-family houses, multi-family houses, or apartment blocks. The main approaches applied to model the retrofitting profits were Consolis Energy +, parametric-based sensitivity analysis, and life-cycle-based economic assessment.Based on the theoretical modeling and analytical results from the case studies, it was found that the energy-saving potential is strongly dominated by the building type, which affects the design of retrofitting toolkits and defines life cycle costs. The results show that improving the efficiency of heat recovery in exhaust ventilation systems is an effective retrofitting measure for energy demand savings in the studied building types. However, the efficiency of other measures is highly dependent on the typology of the buildings. From an economic perspective, toolkits that include all of the possible retrofitting measures may not lead to larger expected reduction in LCC compared to standard retrofits that only include the most sensitive parameters. In addition, the impacts of energy price changes to the LCC in the future are highly diverse in different types of residential buildings. Developing systematic retrofitting guidelines for Swedish residential buildings requires both further research and a close collaboration between all stakeholders involved in the retrofitting process. / <p>QC 20131118</p>
12

Assessing energy and thermal comfort of domestic buildings in the Mediterranean region

Georgiou, Georgios January 2015 (has links)
Nowadays, buildings are responsible for the 40% of energy consumption in the European Union, with energy up to 68% being coherent with thermal loads. Acknowledging the great potential of building sector, a substantial amount of the current building inventory must be refurbished, based on the trade-offs between energy and thermal comfort. To this effect, this study investigates the impact of retrofitting measures in residential envelope for areas experience Mediterranean climate. Seven detached houses, located in Cyprus, were modelled, investigating 253 parameters of envelope interventions and also, 7,056 combinations of these measures. In general, the findings revealed a seasonal performance variation of interventions with regards to the outdoor climate. The application of roof insulation determined as the most economic viable solution during retrofitting (single interventions), achieving a reduction up to 25% of annual energy consumption with enhancement of the indoor thermal environment. In the perspective of synergies between interventions, the application of roof and external walls thermal insulation with upgrade of glazing system with double Low-E demonstrated exemplary levels of performance decreasing on average energy consumption up to 38%.The findings of this research will contribute on the development of guidelines for designers and house builders for a perceptual retrofitting of existing residential envelopes in Cyprus and also, for countries experiencing the Mediterranean climate.
13

Assessment of user satisfaction of restrooms with existing toilet fixtures and new low consumption fixtures

Vankamamidi, Neelima Raman 15 November 2004 (has links)
This research in Langford Building 'A', Texas A&M University, is an attempt to determine the user satisfaction of the new, low consumption toilet fixtures and lavatory valves. 253 surveys were given to the subjects, during the four phases of upgrading the restroom fixtures, to find and compare user satisfaction in each phase. The four phases were: 1. The as-is condition of the flush valves and the lavatory valve. 2. Low consumption manual flush valve and low consumption manual lavatory valve. 3. Old style low consumption automatic flush valve and low consumption automatic lavatory valve. 4. Low consumption manual flush valve and low consumption automatic lavatory valve. The survey analysis for the building showed a positive response from the users for the low consumption valves, but not for the automatic valves, as they did not function as they were expected to.
14

Retrofitting closed golf courses

Plummer, Audrey L. 27 August 2014 (has links)
In the 80s and 90s in America, residential developers believed that the best way to make money was to build a golf course community. Premiums of homes on golf courses ranged from 30% to 100% more than the price of a similar home not adjacent to a course. Today, the bottom has fallen out of the golf market leaving over 2,400 courses closed in America. Residential homes bordering a closed golf course experience an 11.7% loss of value. Many owners and potential developers want these large parcels of land to be up-zoned so they can build higher density residential and make a profit. Neighbors do not want to lose their greenspace and public officials do not want to be seen as harming single-family residential. This thesis argues that to retrofit a closed golf course, developers, community members and other stakeholders must first understand the morphological and environmental implications of the different types of golf courses, the context surrounding closed courses and the location of these courses in a greater regional area. By understanding closed golf courses in this way, a framework can be established that results from negotiation among golf course residents, neighbors, developers and public officials.
15

Upínací systémy dílců u CNC obráběcích center a navržení možnosti zdokonalení

Nováček, Jiří January 2014 (has links)
These diploma thesis is focused on the research of particular camping systems of sections for CNC machining centres. It's focused on the proposal of an improvement of elected CNC machine. The first part consists of a drawing documentation and making of functional prototype of a clamping system. The second part contents theoretical proposal of a new clamping system and consequently the making of a computer model.
16

Development of Surface Flaw Thresholds for Pre-Cured Fiber Reinforced Polymer and Groove Size Tolerance for Near Surface Mounted Fiber Reinforced Polymer Retrofit Systems

Kalayci, Ahmet Serhat 16 July 2008 (has links)
Since the introduction of fiber reinforced polymers (FRP) for the repair and retrofit of concrete structures in the 1980’s, considerable research has been devoted to the feasibility of their application and predictive modeling of their performance. However, the effects of flaws present in the constitutive components and the practices in substrate preparation and treatment have not yet been thoroughly studied. This research aims at investigating the effect of surface preparation and treatment for the pre-cured FRP systems and the groove size tolerance for near surface mounted (NSM) FRP systems; and to set thresholds for guaranteed system performance. The research included both analytical and experimental components. The experimental program for the pre-cured FRP systems consisted of a total of twenty-four (24) reinforced concrete (RC) T-beams with various surface preparation parameters and surface flaws, including roughness, flatness, voids and cracks (cuts). For the NSM FRP systems, a total of twelve (12) additional RC T-beams were tested with different grooves sizes for FRP bars and strips. The analytical program included developing an elaborate nonlinear finite element model using the general purpose software ANSYS. The model was subsequently used to extend the experimental range of parameters for surface flatness in pre-cured FRP systems, and for groove size study in the NSM FRP systems. Test results, confirmed by further analyses, indicated that contrary to the general belief in the industry, the impact of surface roughness on the global performance of pre-cured FRP systems was negligible. The study also verified that threshold limits set for wet lay-up FRP systems can be extended to pre-cured systems. The study showed that larger surface voids and cracks (cuts) can adversely impact both the strength and ductility of pre-cured FRP systems. On the other hand, frequency (or spacing) of surface cracks (cuts) may only affect system ductility rather than its strength. Finally, within the range studied, groove size tolerance of +1/8 in. does not appear to have an adverse effect on the performance of NSM FRP systems.
17

SEISMIC SAFETY EVALUATION OF EARTH DAM AND POSSIBLE REHABILITATION METHODS / アースダムの地震時安全性評価と修復法に関する研究

Bhuddarak Charatpangoon 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18569号 / 工博第3930号 / 新制||工||1604(附属図書館) / 31469 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 清野 純史, 教授 三村 衛, 准教授 古川 愛子 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
18

Waking Up from the American Nightmare: Is the Dream Home the Ideal Home?

Stowasser, Nadja 15 June 2020 (has links)
No description available.
19

Building energy retrofitting: from energy audit to renovation proposals : The case of an office building in France

Clément, Paul Francois January 2012 (has links)
Abstract The built environment is responsible for 40% of the global energy demand (1). To reduce building energy consumption, regulations are enhancing the appeal of sustainable constructions. Nevertheless, the rate of construction is low in most of developed countries. Efforts are to be made in existing buildings, namely in office buildings, which are statistically more energy-consuming than residential buildings (3). To conduct an adapted energy retrofitting, an energy audit can be realized as a pre-study. The first step is to realize an inventory of fixture of the building equipment. From that analysis, the building behavior and consumption are modeled with the help of dynamic simulation software. A comparison with the real life energy consumption guides the study to obtain a model close to reality. Energy retrofitting plans can then be created, based on this model and on the inventory of fixture phase. If technically adapted, each retrofitting solution is evaluated in terms of investment cost and energy savings. Building energy audits and recommendation phases are not unique and normalized procedures. More advanced and complex calculations and measurements can improve the result accuracy. Nevertheless, the introduced approach gives a first understanding of a building, by analyzing its strengths and its weaknesses. As a result, the proposed retrofitting solutions are suited to each specific building. This renovation plan can then be used as a first-decision making tool for the various stakeholders included in the retrofitting project. Abstract The built environment is responsible for 40% of the global energy demand (1). To reduce building energy consumption, regulations are enhancing the appeal of sustainable constructions. Nevertheless, the rate of construction is low in most of developed countries. Efforts are to be made in existing buildings, namely in office buildings, which are statistically more energy-consuming than residential buildings (3). To conduct an adapted energy retrofitting, an energy audit can be realized as a pre-study. The first step is to realize an inventory of fixture of the building equipment. From that analysis, the building behavior and consumption are modeled with the help of dynamic simulation software. A comparison with the real life energy consumption guides the study to obtain a model close to reality. Energy retrofitting plans can then be created, based on this model and on the inventory of fixture phase. If technically adapted, each retrofitting solution is evaluated in terms of investment cost and energy savings. Building energy audits and recommendation phases are not unique and normalized procedures. More advanced and complex calculations and measurements can improve the result accuracy. Nevertheless, the introduced approach gives a first understanding of a building, by analyzing its strengths and its weaknesses. As a result, the proposed retrofitting solutions are suited to each specific building. This renovation plan can then be used as a first-decision making tool for the various stakeholders included in the retrofitting project. Abstract The built environment is responsible for 40% of the global energy demand (1). To reduce building energy consumption, regulations are enhancing the appeal of sustainable constructions. Nevertheless, the rate of construction is low in most of developed countries. Efforts are to be made in existing buildings, namely in office buildings, which are statistically more energy-consuming than residential buildings (3). To conduct an adapted energy retrofitting, an energy audit can be realized as a pre-study. The first step is to realize an inventory of fixture of the building equipment. From that analysis, the building behavior and consumption are modeled with the help of dynamic simulation software. A comparison with the real life energy consumption guides the study to obtain a model close to reality. Energy retrofitting plans can then be created, based on this model and on the inventory of fixture phase. If technically adapted, each retrofitting solution is evaluated in terms of investment cost and energy savings. Building energy audits and recommendation phases are not unique and normalized procedures. More advanced and complex calculations and measurements can improve the result accuracy. Nevertheless, the introduced approach gives a first understanding of a building, by analyzing its strengths and its weaknesses. As a result, the proposed retrofitting solutions are suited to each specific building. This renovation plan can then be used as a first-decision making tool for the various stakeholders included in the retrofitting project.
20

Implementação e análise de um retrofitting aplicado em uma máquina de 3 eixos

Peixôto, Wagner Correia 26 February 2016 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-05-22T13:42:24Z No. of bitstreams: 1 arquivo total.pdf: 4721146 bytes, checksum: 62290d20efdd12371f2308dd6752ec65 (MD5) / Made available in DSpace on 2017-05-22T13:42:24Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 4721146 bytes, checksum: 62290d20efdd12371f2308dd6752ec65 (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The computer numerical control machine tools, or CNC machine tools, emerged due to the need of the aviation industry to produce increasingly complex and accurate parts. The retrofitting of machine tools is the modification of a traditional machine for a computer numerical control one. Due to the popularization of computers, electronic components decreased costs, Internet expansion and open source projects, the retrofitting has become increasingly widespread in industry as an option for the purchase of new machine tools with CNC included. The objective of this study was to implement the retrofit on a 3-axis machine from the Precision Engineering Laboratory of the Federal University of Paraíba. For this adaptation, the machine has been modified to use a kit with interface drivers from HobbyCNC and new stepper motors. After the retrofit, it used a 80-XL Laser system for measuring position errors. The tests were performed on each axis, commanding the machine to five positions and measuring the actual positions reached and, then, the same tests were carried out in reverse direction. With the measured results, the positioning errors, hysteresis, repeatability and accuracy calculated by ISO 230-2 standard. It was conducted other tests in compensating the previously measured errors on the Y axis. There was a significant improvement on the Y-axis accuracy after compensation. Also, angular errors tests were carried out, with the use of an electronic level Talyvel 5, along the axis Y. The results of the test were satisfactory and the retrofitting reached its expectations, providing the possibility of further research in the area of numerical control. / As máquinas-ferramentas com controle numérico computadorizado, ou máquinasferramentas CNC, surgiram devido à necessidade da indústria da aviação para produzir peças cada vez mais complexas e precisas. O retrofitting de máquina-ferramenta é a modificação de uma máquina tradicional para uma com controle numérico computadorizado. Devido à popularização dos computadores, diminuição de custos dos componentes eletrônicos, expansão da Internet e projetos de código aberto, o retrofitting tornou-se uma opção cada vez mais comum na indústria como alternativa para a compra de novas máquinas-ferramentas com CNC incluso. O objetivo deste estudo foi a implementação do retrofitting em uma máquina de 3 (três) eixos no Laboratório de Engenharia de Precisão da Universidade Federal da Paraíba. Para essa adaptação, a máquina foi modificada para utilizar um Kit com drivers de interface da HobbyCNC e novos motores de passo. Após o retrofitting, foi utilizado um sistema Laser XL-80 para medição dos erros de posicionamento. Os testes foram realizados, em cada eixo, comandando-se a máquina para 5 posições e medindo-se as posições reais atingidas e, depois, foram realizados os mesmos testes no sentido inverso. Com os resultados medidos, são calculados os erros de posicionamento, histerese, repetitividade e exatidão conforme a norma ISO 230-2. No eixo Y foi realizado outros testes com a compensação dos erros medidos anteriormente. Houve uma melhora significativa na exatidão do eixo Y após a compensação. Também foram realizados testes de erros angulares, com a utilização de um nível eletrônico Talyvel 5, ao longo do eixo Y. Os resultados obtidos no teste foram satisfatórios e o retrofitting atingiu suas expectativas, por proporcionar a possibilidade de realizar mais pesquisas, na área de Comando Numérico Computadorizado.

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