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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

The effects of immigration on income distribution: The Swedish case

Ung, Kevin, Olsson, Isabela January 2019 (has links)
The purpose of this essay is to study what impact immigration has on the Swedish income distribution for the period 1992-2005. This essay uses a two-folded approach to study the income distribution, first, an income inequality measure will be investigated in order to find if the inequality increases or decreases by the increased immigration. Secondly, we estimate a quantile regression for the 10th, 50th and 90th percentiles for the period 1992, 1995, 2000 and2005, together with an OLS regression in order to find the income gap between the immigrants and natives, which is analysed for males and females separately. The study found that the inflow of immigrants increased income inequality in the lower tail of the income distribution. Immigrants at the upper tail of the income distribution are doing relatively better than the immigrants in the lower tail of the income distribution. Conclusively, independently of gender, the income gap between immigrants and natives is almost three times as large in the lower tail of the income distribution relative to the upper tail of the income distribution.
12

Breakthrough analysis for filtering facepiece media and respirators with activated carbon

Clinger, Jayson C. 01 May 2018 (has links)
Disposable filtering facepiece respirators (FFRs) include a wide range of products that may be certified or non-certified. Many of these respirators are being produced with activated carbon claiming nuisance level organic vapor (OV) relief. OV includes a wide range of volatile organic compounds (VOCs) which have been linked to major and minor health discomfort such as headaches, upper extremity discomfort, nausea, respiratory irritation, asthma nervous system complications, hearing loss, cancer, and death. Common industries that have been identified that may expose employees to nuisance level OV, resulting in minor symptoms, include beautician salons, dry cleaning operations, and pesticide applications. FFRs with activated carbon (FFR-AC) may provide a more convenient alternative for reusable respirators which could also protect employees from OV exposure. This study investigated the adsorption capabilities of one certified respirator (3M) and two alternatively designed respirators (RZ Hunting Mask, Surgical Mask) with activated carbon filtering media. The three FFRs were tested to determine the 50% breakthrough time for two hydrocarbons and one non-carbon-based vapor. 50% breakthrough was chosen because we felt that reducing nuisance level exposures by half would still be protective. Non-certified respirators were exposed to 15 parts per million (ppm) and 50 ppm for all three vapors. Concentrations of 15 ppm and 50 ppm were standardized to achieve similar mass per time exposures across all contaminants and because these values represented the range of nuisance level exposure documented in literature. The 3M respirator was exposed to 15 and 50 ppm of acetone and ammonia, and perchloroethylene was evaluated at 50 ppm. Perchloroethylene was not evaluated at 15 ppm because breakthrough was longer than 8 hours. 3M respirators were also evaluated at 95% relative humidity using 50 ppm of acetone, ammonia, and perchloroethylene. The total number of trials was 43 (n=43). These contaminants and concentrations were chosen based on published data on occupational exposures. The non-certified respirators, (RZ Hunting Mask and Surgical Mask) , were ineffective for all vapors and offered less than 10 minutes of protection before 50% breakthrough occurred. Respirators performed poorly, when exposed to ammonia, with breakthrough less than 5 mins at 50 ppm and 10 minutes at 15 ppm. The 3M respirator had the longest breakthrough times for all trials. Acetone breakthrough occurred at 121 minutes for 50 ppm and 233 minutes at 15 ppm. Perchloroethylene took over 400 minutes to achieve 50% breakthrough at 50 ppm. When acetone at 50 ppm and perchloroethylene at 50 ppm were evaluated with 95% R.H. breakthrough times decreased to 39 and 144 minutes respectively, a nearly 70% decrease in time for both vapors. The results of this study show that non-certified respirators advertised as nuisance level relief may not offer protection for OV. Certified respirators show much more promise, but their performance is highly dependable upon the characteristics of the vapor and environment the respirators are being used in. Additional research is needed to increase our understanding of FFR-ACs performance under more conditions.
13

Twilight Zones and Cornerstones: A Gnat Robot Double Feature

Flynn, Anita M., Brooks, Rodney A., Tavrow, Lee S. 01 July 1989 (has links)
We want to build tiny gnat-sized robots, a millimeter or two in diameter. They will be cheap, disposable, totally self-contained autonomous agents able to do useful things in the world. This paper consists of two parts. The first describes why we want to build them. The second is a technical outline of how to go about it. Gnat robots are going to change the world.
14

Analysis of post-use hypodermic needle medical waste disposal

Heffner, Heather Ann 07 June 2004 (has links)
No description available.
15

Beleaf : an earth-friendly solution to disposable dinnerware

Adhikary, Amrita Prasad 18 July 2011 (has links)
This report is a documentation of an investigative design process that looks at how small shifts in established systems can be reconfigured to make big changes. It is an attempt at establishing a framework for designing sustainable solutions with the environment and social good in mind. In addressing the problems resulting from our indiscriminate use of plastic disposable dinnerware and offering a viable and earth-friendly system solution to the same, I am interested in reminding fellow designers that accountability towards the environment is the new design reality. The report advocates methods that synthesize design for people, profit, and most importantly, the planet. By using plates made from fallen leaves, the user fulfills his specific need for disposable dinnerware while simultaneously participating in an environmental task of closing the loop through responsible disposal and composting. / text
16

Evaluation of Wear Experience with Silicone Hydrogel Lenses in Current Silicone Hydrogel Planned Replacement Lens Wearers

Rutschilling, Ryan R. 04 October 2021 (has links)
No description available.
17

ON-CHIP PASSIVE FLUIDIC MICROMIXER AND PRESSURE GENERATOR FOR DISPOSABLE LAB-ON-A-CHIPS

HONG, CHIEN-CHONG January 2004 (has links)
No description available.
18

A DISPOSABLE BIOSENSOR ARRAY FOR MONITORING HUMAN METABOLIC PARAMETERS AND ITS APPLICATIONS

GAO, CHUAN 13 July 2005 (has links)
No description available.
19

[en] DISPOSABLE TABLEWARE: CONTRIBUTIONS, DAMAGE, NEW POSSIBILITIES AND THEIR CULTURAL BARRIERS IN RIO DE JANEIRO / [pt] UTENSÍLIOS DE MESA DESCARTÁVEIS: CONTRIBUIÇÕES, DANOS, NOVAS POSSIBILIDADES E SUAS BARREIRAS CULTURAIS NO RIO DE JANEIRO

CLAUDIA VANESSA OLIVEIRA COUTO 28 September 2020 (has links)
[pt] Esta pesquisa tem, como ponto de partida, a mudança da matéria-prima utilizada na produção de utensílios de mesa descartáveis, hoje, em sua maioria, produzidos utilizando insumos derivados do petróleo e sendo gradativamente substituídos pelos insumos derivados de fontes renováveis. Esse processo de substituição se intensificou nos últimos anos devido à poluição plástica, tornando-se uma tendência impulsionada, principalmente, por leis em diversos países quanto à obrigatoriedade de biodegradação mais acelerada. Essa conversão da matéria-prima desencadeia mudanças no fim de vida desses produtos que podem ser compostados, permitindo um ciclo de vida mais sustentável, grande problema encontrado com os similares de plástico, cujo fim de vida gera problemas praticamente sem solução. Diante dessas novas características, e com a possibilidade de sistemas produtivos mais sustentáveis, podemos pensar em nos beneficiar de um hábito que lutamos para mudar, que é o da descartabilidade. Com atributos mais sustentáveis, os novos utensílios de mesa descartáveis podem auxiliar num ponto muito importante, na manutenção dos recursos hídricos. As previsões hídricas para os grandes centros urbanos brasileiros, principalmente em relação à região sudeste, revelam a possibilidade de colapso hídrico em 2040. Na lavagem de um copo, são gastos até 1200 ml, o que nos indica que o impacto hídrico doméstico pode ser significativo e a possibilidade do uso doméstico de utensílios de mesa descartáveis compostáveis pode re-presentar uma opção intermediária e de possível execução, caso necessário. Esse trabalho busca estimular esta discussão e se adiantando a possíveis mudanças, investigar porque os utensílios de mesa descartáveis ainda não são usados domesticamente, a fim de identificar possíveis barreiras à implementação desta nova proposta. Os resultados da pesquisa confirmaram que ainda não temos o hábito de usar utensílios de mesa descartáveis na nossa rotina doméstica e que existem barreiras criadas pelo uso do plástico e suas implicações. Mas que o comportamento vem mudando de maneira silenciosa e fluida, pois mais de 80 por cento dos entrevistados pedem comida em domicílio, configurando o uso de descartáveis no âmbito doméstico. Esses descartáveis ainda são deriva-dos do petróleo, aumentando a poluição plástica e seus impactos. / [en] The starting point of this research is to change the raw material used in the production of disposable tableware, which today is mostly produced using petroleum-based inputs and is gradually replaced by inputs from renewable sources. This substitution process has intensified in recent years due to plastic pollution, becoming a trend driven mainly by laws in several countries regarding the obligation of faster biodegradation. This conversion of the raw material triggers changes in the end of life of these products that can be composted, allowing a more sustainable life cycle, a major problem encountered with similar plastics, whose end of life generates problems almost without solution. Faced with these new characteristics, and with the possibility of more sustainable production systems, we can think of benefiting from a habit we struggle to change, which is that of disposability. With more sustainable attributes, the new disposable tableware can help at a very important point in the maintenance of water resources. The water forecasts for the large Brazilian urban centers, especially in relation to the Southeast region, reveal the possibility of water collapse in 2040. In the washing of a cup, up to 1200 ml are spent, which indicates that the domestic water impact can be significant and the possibility of domestic use of compostable disposable tableware can represent an intermediate option and possible execution if necessary. This work seeks to stimulate this discussion and in advance of possible changes, to investigate why disposable tableware is not yet used domestically in order to identify possible barriers to the implementation of this new proposal. The results of the research confirmed that we are not yet in the habit of using disposable tableware in our domestic routine and that there are barriers created by the use of plastic and its implications. But that the behavior has been changing in a silent and fluid way, as more than 80 percent of the interviewees order food at home, configuring the use of disposables in the domestic setting. These disposables are still derived from oil, increasing plastic pollution and its impacts.
20

Simulação de reciclagem de fraldas pós-consumo, esterilizadas por radiação gama

Cunha, Kátia Lúcia da Silva Gonçalves 19 February 2016 (has links)
Submitted by Georgia Vaz (georgia.vaz@mackenzie.br) on 2016-07-07T21:20:26Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Kátia Lucia da Silva Gonçalves Cunha.pdf: 8068781 bytes, checksum: ed19238146c2f43be9d3c93dc70712b7 (MD5) / Made available in DSpace on 2016-07-07T21:20:26Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Kátia Lucia da Silva Gonçalves Cunha.pdf: 8068781 bytes, checksum: ed19238146c2f43be9d3c93dc70712b7 (MD5) Previous issue date: 2016-02-19 / The growing concern for the environment, driven by the increasing difficulty in depositing waste in landfills, has encouraged the search for alternatives to the waste through recycling. The need to reclaim waste is not new, however, still is given little importance to proper environment dispose of diapers. In Brazil, several materials that could be recycled, are still designated to dumps generating, as well as, an environmental problem, an economic problem. After the implementation of the National Policy on Solid Waste, waste come to be considered good value, when is possible to be reused. Disposable diapers residues in most countries, has the final destination in landfills or incinerators and represent a large portion of the waste. Disposable diapers have a wide variety of natural and synthetic polymeric materials of high quality, which is desirable to reuse the same. The technologies currently known to recycle diapers are not satisfactory, due to the process of implementation issue that, generate large amounts of pollutants and organic waste, high spending of energy, in addition the difficulty in promote an efficient sterilization. This work aimed to research new technologies for the recycling of disposable diapers using radiation as a method for sterilization, also observe the effects of radiation on the mechanical, thermal, rheological and morphological properties of the obtained blends and composites. To develop this work and research of new technologies, was performed the characterization of the components of the disposable diaper, it was obtained and applied artificial solution urine, after were sterilized by gamma radiation, mechanical recycling, development of polymer blends and composites and obtaining and characterization of tests samples. The tests aimed to characterize the components of the disposable diapers and blends and composites obtained. Thermal, morphological, chemical, rheological and mechanical tests were performed. The results showed that irradiation acted differently and in isolation in each component of the disposable diaper in the presence of artificial urine solution, caused significant changes in superabsorbent polymers, improving the mechanical recycling process and enabling cost reduction in same. The recycling of disposable diapers can keep some properties and changing others. It was observed that the absence of the superabsorbent polymer influences to improve, not only the stages of recycling, as well as, in thermal and mechanical properties. It highlights the importance of recycling these materials, now worthless, however, of great environmental impact because of the advantages to providing low weight products, also obtaining economic and environmental advantages. / O crescimento da preocupação com o meio ambiente, impulsionado pela crescente dificuldade em depositar os resíduos em aterros, tem incentivado a busca de alternativas para o resíduo através de reciclagem. A necessidade de se reaproveitar resíduos não é nova, contudo, ainda é dada pouca importância para a disposição ambientalmente correta das fraldas descartáveis. No Brasil, muitos materiais que poderiam ser reciclados continuam sendo destinados a aterros sanitários gerando, além de um problema ambiental, um problema econômico. Após a implantação da Política Nacional de Resíduos Sólidos, os resíduos passaram a ser considerados bens de valor, quando possível seu reaproveitamento. Os resíduos de fraldas descartáveis, na maioria dos países, têm o destino final em aterros ou incineradores e representam uma grande parcela do refugo. As fraldas descartáveis possuem uma vasta variedade de materiais poliméricos naturais e sintéticos de alta qualidade, o que torna desejável o reaproveitamento dos mesmos. As tecnologias conhecidas atualmente para a reciclagem de fraldas não são satisfatórias devido ao problema de implementação do processo que geram grandes quantidades de poluentes e resíduos orgânicos, alto gasto energético, além da dificuldade em promover uma esterilização eficiente. Este trabalho teve como principal objetivo a pesquisa de novas tecnologias para a reciclagem de fraldas descartáveis pós-consumo, utilizando a radiação gama como método para a esterilização, também observar os efeitos da radioesterilização nas propriedades mecânicas, térmicas, reológicas e morfológicas das blendas e compósitos obtidos. Para o desenvolvimento deste trabalho e pesquisa de novas tecnologias, realizou-se a caracterização dos componentes da fralda descartável, obtenção e aplicação de solução de urina artificial, esterilização, reciclagem mecânica, desenvolvimento de blendas e compósitos e obtenção e caracterização de corpos de provas. Os ensaios visaram a caracterização dos componentes da fralda descartável e das blendas e compósitos obtidos. Foram realizados ensaios térmicos, morfológicos, químicos, reológicos e mecânicos. Os resultados mostraram que a irradiação, agiu de forma diferente e isolada em cada componente da fralda descartável, na presença de solução de urina artificial, provocou modificação do polímero superabsorvente, viabilizando o processo de reciclagem mecânica e possibilitando a redução de custos no mesmo. A reciclagem de fraldas descartáveis é possível mantendo algumas propriedades e alterando outras. A ausência do polímero superabsorvente, influenciou para a melhoria, não só das etapas de reciclagem, como também em propriedades térmicas e mecânicas. Destaca-se a importância de reaproveitamento destes materiais, atualmente sem valor, porém, de grande impacto ambiental, devido as vantagens em proporcionar produtos de baixo peso, obtendo também vantagens econômicas e ambientais.

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