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Lifetime monitoring of appliances for reuseMazhar, Muhammad Ilyas, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2006 (has links)
Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. Therefore, manufacturers are struggling to find ways to recover maximum value from returned products. This goal can best be achieved by promoting multiple reuse programs as reuse is one of the most effective ways to enhance a sustainable engineering economy. Since the essential goal of the reuse strategy is to reuse parts, the reliability of used parts becomes a core issue. Research indicates that reuse is technologically feasible, associated with a significant manufacturing cost saving, and it does not compromise product quality. However, it is not easy to be applied in reality. There are several uncertainties associated with reuse, the most common is the uncertainty of the product???s quality after use. A widespread implementation of the reuse strategy could be triggered, subject to the availability of reliable methods to assess the useful remaining life of parts. The evolution of such a methodology would play a pivotal role in making decisions on the supply chain process and the recovery value of returned products. Reliability assessment by life cycle data analysis is the basis of this research. The proposed methodology addresses the problem of reliability assessment of used parts by considering two important aspects. It performs statistical as well as condition monitoring data analysis for decision-making on reuse. The analysis is carried out in two stages. Firstly, a wellknown reliability assessment procedure, the Weibull analysis, is applied to analyse time-tofailure data to assess the overall reuse potential of components. In the second stage, the used capacity (actual life) of components is determined by analysing their operating history (condition monitoring data). The linear and nonlinear regression analysis, Kriging procedures and artificial neural networks (ANN) are employed in this stage. Finally, the Weibull analysis and ANNs are integrated to estimate the remaining useful life of components/assemblies of a product at the end of its first life cycle. The model was validated by using life cycle data from consumer products.
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Lifetime monitoring of appliances for reuseMazhar, Muhammad Ilyas, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2006 (has links)
Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. Therefore, manufacturers are struggling to find ways to recover maximum value from returned products. This goal can best be achieved by promoting multiple reuse programs as reuse is one of the most effective ways to enhance a sustainable engineering economy. Since the essential goal of the reuse strategy is to reuse parts, the reliability of used parts becomes a core issue. Research indicates that reuse is technologically feasible, associated with a significant manufacturing cost saving, and it does not compromise product quality. However, it is not easy to be applied in reality. There are several uncertainties associated with reuse, the most common is the uncertainty of the product???s quality after use. A widespread implementation of the reuse strategy could be triggered, subject to the availability of reliable methods to assess the useful remaining life of parts. The evolution of such a methodology would play a pivotal role in making decisions on the supply chain process and the recovery value of returned products. Reliability assessment by life cycle data analysis is the basis of this research. The proposed methodology addresses the problem of reliability assessment of used parts by considering two important aspects. It performs statistical as well as condition monitoring data analysis for decision-making on reuse. The analysis is carried out in two stages. Firstly, a wellknown reliability assessment procedure, the Weibull analysis, is applied to analyse time-tofailure data to assess the overall reuse potential of components. In the second stage, the used capacity (actual life) of components is determined by analysing their operating history (condition monitoring data). The linear and nonlinear regression analysis, Kriging procedures and artificial neural networks (ANN) are employed in this stage. Finally, the Weibull analysis and ANNs are integrated to estimate the remaining useful life of components/assemblies of a product at the end of its first life cycle. The model was validated by using life cycle data from consumer products.
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An embarrassment of riches : rekindling desire for obsolete furniture : a exegesis presented in partial fulfilment of the requirements for the degree of Master of Design, Massey University, Wellington, New ZealandNeale, Wendy January 2010 (has links)
This exegesis tells the story of my Master of Design project, Embarrassment of Riches. During this project I have gleaned obsolete furniture pieces and operated on them to present new possibilities. This text discusses the body of work I have created in the context of three main ideas: the use of gleaning, intervention and the role played by memory in rekindling desire. I have focussed on making in a heuristic, research-through-design practice, testing ideas through making/reflecting and then developing my ideas further in new pieces. Combining this actionresearch method with bricolage has enabled me to critically self-reflect on my practice. Through this I have discovered that I can continue to design and create objects in an age of overproduction and consumption. With ecological considerations in mind I can make obsolete objects desirable (again) by encouraging people to feel intimate with them. I intervene in the objects’ interstices to suggest histories that kindle engagement and attachment. The interstice has been a rich source of inspiration, not only as site of intervention, but as site where experimentation occurs, a process by which objects are found and a space where new genres develop.
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Modified comparative life cycle assessment of end-of-life options for post-consumer products in urban regionsGuidry, Caroline. January 2008 (has links)
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Bras, Bert; Committee Member: Paredis, Chris; Committee Member: Realff, Matthew.
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Durability performance of coarse crushed concrete aggregate structural concreteDodds, Wayne J. January 2017 (has links)
Crushed or recycled concrete aggregates (CCA/RCA) is an increasingly popular material as a replacement for natural aggregates in concrete due to industry demands for more recycled, lower carbon and responsibly sourced materials. In the UK, the majority of CCA is utilised in non-structural applications such as: a general fill material, road base/subbase or in low-grade concrete. Recycled aggregate producers however, are seeking new ways to incorporate CCA into higher value applications such as structural concrete to increase profits. Opportunities to incorporate CCA into structural concrete may also arise because of project demands for sustainability or in situations where natural aggregates are in short supply. Limited research has been published regarding the effect of coarse CCA on the durability of structural concrete, particularly in respect to water and chloride ion ingress and possibility of corrosion initiation. The aim of this EngD research programme was to investigate the effect of coarse CCA and supplementary cementitious materials (SCMs) on the durability performance of structural concrete, with particular emphasis on the key liquid transport mechanisms within concrete, namely absorption by capillary action, diffusion and migration. This addressed an industry concern regarding the detrimental effect of coarse CCA which has resulted in a limit on replacement levels of coarse natural aggregates in structural concrete, as defined in Eurocodes and local national standards for concrete. In this study, structural concrete was produced with varying levels of coarse CCA replacement (up to 100%), from five different sources and/or structural elements across the UK, with various combinations of SCMs to replace in part the Portland cement. Petrographic analysis was used as an innovative technique to characterise the coarse CCA sources to determine suitability which yielded positive results. The durability performance of the resultant concrete was analysed by exposing the concrete to aggressive chloride environments. The results indicate that the inclusion of coarse CCA, even as low as 20%, had a detrimental effect on the durability performance of structural concrete, in relation to absorption by capillary action, diffusion and migration. This effect however, can be offset through the use of SCMs, which have been shown to outperform control Portland cement concrete with 100% natural aggregates in durability performance tests. The results also suggest that cementitious materials had a greater influence on durability performance than the type and source of coarse aggregates used. It is recommended that the replacement of natural aggregate with coarse CCA be limited to 30% in cases where compliance with the 28 day characteristic strength is of particular importance. If the criterion for compliance at 28 days can be relaxed and the compressive cube strength of concretes with SCMs tested at later ages for conformity (56 or 90 days), then higher quantities of coarse CCA may be incorporated up to 60% to produce a more sustainable structural concrete. It is recommended that Portland cement is partially replaced with 50% ground granulated blast-furnace slag (GGBS) to produce a CEM III/A concrete. This is a significant step towards the potential wider implementation of coarse CCA in structural concrete, provided a suitable quantity of SCM is adopted along with a reliable and consistent source of coarse CCA.
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Avaliação de sustentabilidade em cooperativas de reciclagem de Porto Alegre∕RSAccorsi, Regiane Juchen Machado January 2018 (has links)
Esta dissertação busca mensurar a sustentabilidade através do desempenho de cooperativas de catadores de material reciclado de Porto Alegre a partir de indicadores e índices de sustentabilidade utilizados por Besen (2011), em uma perspectiva de sustentabilidade econômica, ambiental, social, de saúde e institucional. Esta pesquisa avaliou as cooperativas a partir de 17 indicadores de sustentabilidade. Os dados consistiram na aplicação de questionário padrão contendo perguntas que buscaram responder a aspectos legais e dimensão institucional, infraestrutura física e operacional da cooperativa, renda e benefícios para os cooperados, condições gerais de trabalho, parcerias e apoios. Os resultados evidenciaram que para o fortalecimento da inclusão de catadores em associações e cooperativas, é necessário a intervenção direta do governo, através de políticas públicas voltadas para a criação de capital social nos grupos e comunidades pobres, uma vez que as cooperativas ainda necessitam muito do aporte institucional da Prefeitura de Porto Alegre, tanto na proposição de ações de melhoria nas condições de trabalho quanto na dependência da entrega do material reciclável, a necessidade de que a prefeitura contrate as cooperativas para a realização da coleta seletiva, conforme preconiza a Política Nacional de Resíduos Sólidos, pois isto aumentaria a renda dos cooperados, gerando um incentivo para a estabilização jurídica, contábil e financeira das mesmas. Além disso, com esta mudança de patamar as cooperativas trocariam um cenário de instabilidade e dependência por um novo, no qual possibilidades de investimento e crédito podem começar a fazer parte do universo dos cooperados. / This dissertation seeks to measure sustainability through the performance of cooperatives of collectors of recycled material of Porto Alegre using indicators and sustainability indexes developed by Besen (2011), in a perspective economic sustainability, environmental, social, institutional and health. The research assessed the cooperatives examining 17 indicators of sustainability. The data informing the indicators came from the application of standard questionnaire containing questions that sought to assess the legal aspects and institutional dimension, physical infrastructure the cooperative's income the benefits provided for members, general conditions of work, partnerships and other types of support. The results showed that to strengthen social inclusion of scavengers organized in associations and cooperatives, Government has to offer strong support, through public policies focused on the creation of social capital in groups and poor communities. The cooperatives need more institutional support from Porto Alegre municipal government that has to develop actions to improve working conditions in the cooperatives as well as to assure the delivery of recyclable material to them. Municipal government should hire the cooperatives for selective collection, as stated in the national Policy of Waste, since it would increase the income of the cooperative members, creating an incentive for their stabilization in legal financial terms. A strong municipal support will transform the cooperatives from instability to more stable and socially inclusive organizations in which investment and credit opportunities would make a difference for its members.
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Estudo de propriedades mecânicas de concretos produzidos com diferentes agregados recicladosSilva, Karlisson André Nunes da 11 March 2011 (has links)
The research aimed to evaluate the mechanical properties of concrete produced with recycled coarse aggregate, at ages 28 days and 240 days for use in structural elements. We used two types of waste: a mixture of waste consisting of construction, renovation and demolition waste and others just concrete. The first was collected on the campus of Federal University of Alagoas, the second was from research papers and several samples of concrete works of Macedonia and other cities in the state. After the processing of waste, only the coarse aggregate were used. For the production of concrete were considered two ratios a / c (0.4 and 0.5) and two levels of substitution of coarse aggregate (100% RCD and 100% Concrete). The implementation of these combinations were defined using 22 factorial design for the age of 28 days. The properties studied were compressive strength and modulus of elasticity. From the results obtained by statistical analysis to the age of 28 days was observed that the compressive strength of concrete obeyed the Law of Abrams and the w / c ratio had a significant effect on this property. As for the modulus of elasticity specifies the mass had a greater influence on its outcome. With regard to older concrete mechanical properties mentioned above had a satisfactory outcome when compared to reference concrete. The results show that the use of concrete with coarse aggregate of both types may be viable for certain class of concrete strength. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A pesquisa teve como objetivo principal avaliar as propriedades mecânicas dos concretos produzidos com agregados graúdos reciclados, nas idades de 28 dias e 240 dias, para uso em elementos estruturais. Utilizaram-se dois tipos de resíduos: um formado da mistura de resíduos de construção, reforma e demolição, e outro apenas de resíduos de concreto. O primeiro foi coletado dentro do campus da Universidade Federal de Alagoas; o segundo foi proveniente de trabalhos de pesquisa e de amostras de concretos de várias obras de Maceió e outros municípios do estado. Após o beneficiamento dos resíduos, apenas os agregados graúdos foram utilizados. Para a produção dos concretos foram consideradas duas relações a/c (0,4 e 0,5) e dois níveis de substituição do agregado graúdos (100% RCD e 100% Concreto). As combinações para execução dos mesmos foram definidas através de planejamento fatorial 22 para a idade de 28 dias. As propriedades analisadas foram a resistência à compressão e o módulo de elasticidade. A partir dos resultados obtidos, através da análise estatística para a idade de 28 dias foi possível observar que a resistência à compressão dos concretos obedeceu a Lei de Abrams e que a relação a/c teve efeito significativo sobre está propriedade. Já para o módulo de elasticidade a massa especifica teve uma maior influência sobre o seu resultado. Com relação aos concretos de idade mais avançada as propriedades mecânicas citadas acima apresentaram uma evolução satisfatória quando comparados aos concretos de referência. Os resultados mostram que o uso de concretos com agregados graúdos de ambos os tipos podem ser viáveis para determinadas classe de resistência do concreto.
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Estudo da utilização de resíduo de casca cerâmica de microfusão no concreto em substituição ao agregado graúdo e miúdo naturalTedesco, Marina January 2016 (has links)
O Brasil destaca-se como o sétimo produtor mundial de fundidos, com mais de 30 empresas de microfusão localizadas nas regiões Sul e Sudeste do país eum dos grandes desafios é a gestão dos resíduos, entre eles, a casca cerâmica. Para a mitigação dos seus impactos é necessário o uso de técnicas de reciclagem que combinem desenvolvimento técnico com proteção ao meio ambiente e utilize a construção civil, mais especificamente o concreto, como fonte de incorporação do resíduo de casca cerâmica. Para isso, foi estudado o resíduo como agregado graúdo e miúdo em comparação com a areia e a brita 0. A massa específica do agregado seco e a massa unitária dos agregados foram avaliadas, sendo que o resíduo apresentou uma pequena redução para ambos os casos. A absorção de água foi maior para o agregado reciclado. O agregado miúdo reciclado apresentou resultados maiores para o módulo de finura e a massa específica. O índice de forma do agregado graúdo reciclado apresentou melhores resultados do agregado natural. Para avaliação do comportamento do resíduo no concreto foi utilizado o método de dosagem do IPT EPUSP. A relação água/cimento aumentou com a incorporação do resíduo Ainda, houve redução do consumo de cimento com o resíduo incorporado. As adições com até 75% de substituição do agregado graúdo apresentaram maior resistência à compressão axial comparado ao concreto convencional e, quanto maior a relação a/c menor a resistência à compressão obtida.Para o concreto em estado endurecido a absorção de água aumentou com a adição de resíduo. O índice de vazios do concreto aumenta com a incorporação de resíduo na mistura. A incorporação de resíduo aumenta a massa específica real e da amostra seca das dosagens até a substituição de 50% do agregado graúdo e após esta, tem-se uma pequena redução nestes parâmetros. A espessura carbonatada aumentou com a idade e as dosagens até 50% de adição do agregado graúdo apresentaram valores menores do que o concreto convencional. Palavras-chave: Casca cerâmica, concreto, resíduo, agregado reciclado. / Brazil stands out as the seventh world-wide producer of castings, with more than 30 microfusion companies located in the South and Southeast regions of the country and one of the great challenges is waste management, among them the ceramic shell. To mitigate its impacts, it is necessary to use recycling techniques that combine technical development with protection of the environment and use civil construction, specifically concrete, as a source of incorporation of the residue of ceramic shell. For this, the residue was studied as a large aggregate and small compared to sand and gravel 0. The specific mass of the dry aggregate and the unit mass of the aggregates were evaluated, and the residue presented a small reduction for both cases. The water absorption was higher for the recycled aggregate. The recycled kid aggregate presented higher results for the modulus of fineness and the specific mass. The shape index of the recycled aggregate presented better results from the natural aggregate. To evaluate the behavior of the residue in the concrete, the IPT EPUSP dosing method was used The water / cement ratio increased with the incorporation of the residue. Also, there was a reduction of the cement consumption with the incorporated residue. Additions with up to 75% of the large aggregate substitution showed greater resistance to axial compression compared to conventional concrete, and the higher the a / c ratio the lower the compressive strength obtained. For concrete in the hardened state the water absorption increased with the addition of residue. The void content of the concrete increases with the incorporation of residue into the mixture. Residue incorporation increases the actual specific mass and the dry sample of the dosages up to the replacement of 50% of the large aggregate and after this, a small reduction in these parameters is observed. The carbonate thickness increased with age and the dosages up to 50% addition of the coarse aggregate presented lower values than the conventional concrete.
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Avaliação de sustentabilidade em cooperativas de reciclagem de Porto Alegre∕RSAccorsi, Regiane Juchen Machado January 2018 (has links)
Esta dissertação busca mensurar a sustentabilidade através do desempenho de cooperativas de catadores de material reciclado de Porto Alegre a partir de indicadores e índices de sustentabilidade utilizados por Besen (2011), em uma perspectiva de sustentabilidade econômica, ambiental, social, de saúde e institucional. Esta pesquisa avaliou as cooperativas a partir de 17 indicadores de sustentabilidade. Os dados consistiram na aplicação de questionário padrão contendo perguntas que buscaram responder a aspectos legais e dimensão institucional, infraestrutura física e operacional da cooperativa, renda e benefícios para os cooperados, condições gerais de trabalho, parcerias e apoios. Os resultados evidenciaram que para o fortalecimento da inclusão de catadores em associações e cooperativas, é necessário a intervenção direta do governo, através de políticas públicas voltadas para a criação de capital social nos grupos e comunidades pobres, uma vez que as cooperativas ainda necessitam muito do aporte institucional da Prefeitura de Porto Alegre, tanto na proposição de ações de melhoria nas condições de trabalho quanto na dependência da entrega do material reciclável, a necessidade de que a prefeitura contrate as cooperativas para a realização da coleta seletiva, conforme preconiza a Política Nacional de Resíduos Sólidos, pois isto aumentaria a renda dos cooperados, gerando um incentivo para a estabilização jurídica, contábil e financeira das mesmas. Além disso, com esta mudança de patamar as cooperativas trocariam um cenário de instabilidade e dependência por um novo, no qual possibilidades de investimento e crédito podem começar a fazer parte do universo dos cooperados. / This dissertation seeks to measure sustainability through the performance of cooperatives of collectors of recycled material of Porto Alegre using indicators and sustainability indexes developed by Besen (2011), in a perspective economic sustainability, environmental, social, institutional and health. The research assessed the cooperatives examining 17 indicators of sustainability. The data informing the indicators came from the application of standard questionnaire containing questions that sought to assess the legal aspects and institutional dimension, physical infrastructure the cooperative's income the benefits provided for members, general conditions of work, partnerships and other types of support. The results showed that to strengthen social inclusion of scavengers organized in associations and cooperatives, Government has to offer strong support, through public policies focused on the creation of social capital in groups and poor communities. The cooperatives need more institutional support from Porto Alegre municipal government that has to develop actions to improve working conditions in the cooperatives as well as to assure the delivery of recyclable material to them. Municipal government should hire the cooperatives for selective collection, as stated in the national Policy of Waste, since it would increase the income of the cooperative members, creating an incentive for their stabilization in legal financial terms. A strong municipal support will transform the cooperatives from instability to more stable and socially inclusive organizations in which investment and credit opportunities would make a difference for its members.
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Avaliação do Desempenho de Artefato de Poliestireno de Alto Impacto Reciclado / Evaluation of the Performance of Recycled High Impact PolystireneMarcus André Rego de Araujo 28 July 2006 (has links)
Resíduos plásticos, descartados de placas de publicidade compostas por poliestireno de alto impacto (HIPS), foram reciclados para obtenção de tubos que servem como base de painel de propaganda. O material foi avaliado nas diferentes etapas de reprocessamento, onde sua estrutura foi caracterizada por espectroscopia na região do infravermelho (FTIR) e ressonância magnética nuclear de núcleo de hidrogênio (1H-RMN). Suas propriedades térmicas, mecânicas e morfológicas, também foram estudadas. Os testes e análises instrumentais, aos quais foram submetidos o material ao longo de todo reprocessamento, demonstraram que não houve modificações significativas na estrutura química, na morfologia e no comportamento térmico e mecânico do material. / Plastics residues from advertising plates were recycled for attainment of pipes that serve as base of advertising panels. These residues were composed by high impact polystyrene (HIPS) and the polymer structures were characterized by spectroscopy in the infrared region (FTIR) and hydrogen nuclear magnetic resonance (1H-NMR). Its thermal, mechanical and morphological properties, had been also studied. The instrumental tests and analyses, to which the material had been submitted, had demonstrated that there was not significant modifications in the chemical structure, in the morphology and in the thermal and mechanical behavior of the material after being recycled.
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