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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.
251

An Airline Pilot Attitude Evaluation: Transportation Security Administration's Federal Flight Deck Officer Program

January 2017 (has links)
abstract: The Federal Flight Deck Officer (FFDO) program was mandated legislatively, as part of the Homeland Security Act of 2002. This study replicated earlier research that investigated pilots’ opinions of the current state of the FFDO program based on interviews. A Likert survey was created to allow simpler quantitative collection and analysis of opinions from large groups of pilots. A total of 43 airline pilots participated in this study. Responses to the Likert questions were compared with demographics, searching for significance through a Pearson chi-square test and frequencies were compared to earlier research findings. Significant chi-square results showed that those familiar with the program were more likely to agree the program should continue, it was effective, the screening and selection process of program applicants was adequate and the Federal Air Marshal Service’s management of the FFDO program was effective. Those with Military experience were more likely to disagree it was reasonable that FFDOs were required to pay for their own room and board during training or train on their own time. All those who shared an opinion agreed there should be a suggestion medium between FFDOs and their management. Unlike the prior study, all those familiar with the program agreed the weapons transportation and carriage procedures were adequate. Furthermore, all those who shared an opinion found the holster locking mechanism adequate, which was another reversal of opinion from the prior study. Similar to the prior study, pilots unanimously agree FFDOs were well trained and agreed that the program was effective and should continue. / Dissertation/Thesis / Masters Thesis Aerospace Engineering 2017
252

“Vida cansada”: cotidiano e trabalho no universo mototáxi em Campina Grande-PB.

Timóteo, Anny Glayni Veiga 30 May 2014 (has links)
Submitted by Morgana Silva (morgana_linhares@yahoo.com.br) on 2016-08-31T16:54:50Z No. of bitstreams: 1 arquivototal.pdf: 14406050 bytes, checksum: 6883937022c05720a8a2b2ceeba7330a (MD5) / Made available in DSpace on 2016-08-31T16:54:50Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 14406050 bytes, checksum: 6883937022c05720a8a2b2ceeba7330a (MD5) Previous issue date: 2014-05-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In face of the professional diversity found in urban environment, this work disserts on the appeareance and development of a recent socio-professional category - the one of the moto-taxi pilots - focusing on a specific group of moto-taxi pilots in the city of Campina Grande - PB. Subsidized by the etnographic method, this work was developed through participant observation of a moto-taxi stand, between November of 2012 and August of 2013. The stand XXX, located at the Venancio Neiva St. - city downtown, belongs to the "white motorbikes pilots", i.e. the ones that are registered at the city's Traffic and Public Transportation Office (STTP-CG). With the objective of capturing the diverse situations that can be found in the daily lives of those workers, this research listens to what moto-taxi pilots have to say, considering the conditions that drove them to join this system and their relationships with their families, customers, associates, colleagues, employers, companies and public agents. We aimed on perceiving the tensions and conflicts that rise due to the daily relationship between "freedom" - which main representation would justify their stay in such a though job, and the restrictions to their activities, which are commonly associated to the risk intrinsically related with their job, to the urban violence, to traffic regulation, to the embarrassment by the close relationship with the costumer and the stereotypes that those workers are subject to. / Diante da diversidade profissional encontrada no meio urbano, esta dissertação tem como objetivo refletir sobre o surgimento e perenidade de uma recente categoria sócioprofissional, -o mototaxista-, apresentando como foco um grupo específico de mototaxistas da Cidade de Campina Grande- PB. Subsidiado pelo método etnográfico, este trabalho foi construído a partir de observação participante de um Ponto de mototáxi, entre novembro de 2012 e agosto de 2013. O Ponto XXX, situa-se na Rua Venâncio Neiva, Centro da cidade, pertencendo ao grupo dos “mototaxistas das motos brancas”, ou seja; aqueles que possuem cadastro na Secretaria de Trânsito e Transporte Público de Campina Grande (STTP-CG). Buscandn apreender as diversas situações encontradas no cotidiano desser trabalhadores, a pesquisa voltou-se aos discursos dos mototaxistas, abordando as condições que motivaram seu ingresso no sistema, seu cotidiano nas relações com a família e nas relações de trabalho com clientes, associados, colegas, patrões, órgãos e agentes públicos. Buscamos perceber as tensões e conflitos decorrentes da relação cotidiana entre a "liberdade" -principal representação- justificando sua permanência nessa atividade "cansada" e as restrições às suas atividades, vinculadas à insalubridade no trabalho, à violência urbana, as regulamentações de trânsito, aos constrangimentos nas relações com os clientes e os estigmas recorrentes desta atividade.
253

Tecnologia de preparacao de oxido de uranio(IV) apropriado para conversao a tetrafluoreto de uranio

RIBAS, ANTONIO G.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:28Z (GMT). No. of bitstreams: 1 00034.pdf: 1919974 bytes, checksum: ed7e98a843b601b5ae6e2b59da8aa6bc (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP
254

Usos das cromatografias de extracao e de troca ionica na separacao de torio e terras raras de residuos industriais gerados na unidade de purificacao de torio do IPEN. Aplicacao das terras raras como catalisadores na geracao de hidrogenio / Uses of extraction and ion exchange chromatography in the thorium and rare earths separation from industrial residue generated in thorium purification unity at IPEN. Application of rare earths as catalysts for generation of hydrogen

ZINI, JOSIANE 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:14Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
255

Avaliação da aplicação de lodo de ETA no adensador de lodo de uma ETE de lodos ativados

Peixoto, Gilmar José [UNESP] 30 October 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-10-30Bitstream added on 2014-06-13T18:38:58Z : No. of bitstreams: 1 peixoto_gj_me_ilha.pdf: 3639925 bytes, checksum: e19f2ebbc3c46fda991b86aa7db634e8 (MD5) / No Brasil, existe um problema comum à maioria das comunidades onde o abastecimento público de água é realizado com água superficial e há a necessidade de tratamento. No processo de tratamento ocorre a formação de resíduos na forma de lodo, o qual periodicamente necessita ser descartado do processo. Exceção feita a algumas Estações de Tratamento de Água (ETA), em nível nacional, todas despejam esses resíduos, de forma bruta, sem nenhum tratamento, em corpos de água. O presente trabalho foi realizado com o objetivo de encontrar solução adequada para destinar, de forma correta, o lodo produzido pela ETA da cidade de Presidente Prudente, operada pela Companhia de Saneamento Básico do Estado de São Paulo (SABESP). O estudo baseou-se na premissa em aplicar o lodo da ETA na Estação de Tratamento de Esgotos (ETE), no adensador por gravidade existente. E, para tanto, foi montada uma ETE Piloto, com a qual foram realizadas as simulações de aplicação de cargas de 2000 mg/L e 4000 mg/L de lodo de ETA A avaliação do desempenho da unidade piloto foi conseguida por meio de monitoramento analítico de parâmetros como: pH, temperatura, oxigênio dissolvido, alcalinidade, DBO, DQO, Fósforo, Nitrogênio, sólidos dissolvidos, totais, fixos e voláteis, turbidez, Índice Volumétrico de Lodo (IVL) e Teor de Lodo (TL). Os resultados mostraram que a carga de 2000 mg/L de lodo de ETA no adensador por gravidade, pode ser realizada sem causar problemas. No entanto, com carga de 4000 mg/L, constatou que as aplicações progressivas de lodo devem ser melhor pesquisadas / In Brazil, very common problem to the biggest part of the communities, where the public water supply is realized using the surface water, and needs to pass by the water treatment plant (WTP). In the treatment process, a residue formation in the form of sludge occurs, which periodically needs to be discarded out the process. Except some WTP, on a nation level all they discarded these residues, in brutal way and without treatment, in watercourses. In this work was realized with the objective to finding an adequate solution to properly allocate the sludge produced in the Water Treatment Plant (WTP) from Presidente Prudente, which is operated by SABESP. This study was based in premise to apply the WTP sludge in the Wastewater Treatment Plant (WWTP), in the thickener by an existing gravity. And however, it was built a WWTP Pilot plant where were realized the simulations of applying dosages of 2000 mg/L and 4000 mg/L of WTP sludge. The evaluation of the performance of the pilot unit was gotten by analytical monitoring of many parameters as: pH, temperature, dissolved oxygen, alkalinity, BOD, COD, phosphorus, nitrogen, dissolved solids, fixed and volatile ones, turbidity, Sludge Volumetric Index (IVL) and sludge concentration (TL). The results showed that the application of 2000 mg/l of WTP sludge in the WWTP gravity thickener can be realized without problems. On the other hand the application of 4000 mg/l showed that progressive applications of sludge have to be better researched
256

Enligt lotsen : En studie om lotsars upfattning om kommunikationen med bryggteamet

Andersson, Linus, Johansson, Johan January 2018 (has links)
Detta arbetet genomfördes med syftet att undersöka vad svenska hamnlotsar ansåg om kommunikationen med fartygets bryggteam och även utreda uppkomsten av eventuella kommunikationsbrister. I Sverige sker majoriteten av alla fartygsolyckor inom hamnområdet samt den största olyckskategorin är kommunikation. Arbetet genomfördes som en kvalitativ studie där datainsamlingen bestod av semistrukturerade intervjuer med sex svenska hamnlotsar från två olika lotsområden, för att ge en inblick om deras personliga uppfattning gällande kommunikationen med bryggteamet. Resultatet visar att respondenterna anser generellt att kommunikationen är fullt godkänt ombord på fartyg. Men det framgår även att i vissa fall kan språket vara så pass bristfällig att teckenspråk kan vara det enda sättet att kommunicera på. Arbetets slutsats är att språket ombord är den största bidragande faktorn till att kommunikationsbrister uppstår, därför krävs en förbättring.
257

Incorporação de moinha de carvão vegetal na produção de coques em forno piloto

Orellana, Daniel Rigon January 2016 (has links)
A reutilização de resíduos e sua destinação são desafios seguidamente enfrentados na indústria. Por ser extensa e empregar uma grande variedade de processos, matérias-primas e insumos, a cadeia do aço se beneficia por ter ampla flexibilidade e diversas possibilidades de reintrodução de compostos em sua rota de fabricação. Resíduos carbonosos, por exemplo, podem ser parcialmente usados em misturas de carvões no processo de coqueificação dependendo do tamanho e da composição química. Este trabalho, teve como objetivo, avaliar a influência da adição de moinha de carvão vegetal em uma mistura de carvões para a produção de coques em forno piloto de coqueificação e determinar os teores máximos de incorporação suportados pela mistura, avaliando parâmetros de qualidade do coque. Para isso, a moinha de carvão vegetal de eucalipto foi introduzida em duas frações granulométricas distintas, uma composta por partículas mais grosseiras (fração G) e outra composta por partículas mais finas (fração F), e caracterizado juntamente com a mistura utilizada. Posteriormente, os coques produzidos em forno piloto também foram caracterizados através de diversas análises: imediata, elementar, área superficial, porosidade, textura óptica, reatividade em termobalança, CRI/CSR e DI150/15. Os resultados atingidos mostraram que inserção da fração G de moinha comprometeu menos os parâmetros de qualidade dos coques com carvão vegetal. Teores de até 3% de moinha foram suportados para essa distribuição de tamanho de partícula enquanto que para a fração F, somente 1%. Outro fator observado foi que os coques produzidos com adição de moinha de carvão vegetal não tiveram queda significativa no teor de enxofre, a exceção da amostra contendo 10% de carvão vegetal na fração G. Em todas as amostras com moinha de carvão vegetal também foi possível notar o aumento da área superficial em relação ao coque de referência. Os testes termogravimétricos dinâmicos também trouxeram informações relevantes a respeito das temperaturas e taxas aparentes de reações dos coques feitos com moinha de carvão vegetal. / The reuse of waste materials and its destination are challenges continuously faced for industry. For being far-flung and apply a huge variety of process, raw materials and inputs, the steel supply chain benefits from having a high flexibility and many possibilities of reintroducing compounds in its manufacturing route. For example, carbonaceous materials can be used partially in coal blends for cokemaking process depending on particle size and chemical composition. The current work aimed to evaluate the influence of adding fine charcoal to a coal blend for coke production in a pilot oven and to determine the maximum content tolerated for the blend, assessing coke quality parameters. For this, a eucalyptus charcoal residue was introduced in two different size distributions, one composed of coarser particles (fraction G) and another of finer (fraction F), and characterized together with the coal blend used. Afterwards, the cokes produced in pilot oven were also characterized through several analyzes: proximate, ultimate, surface area, porosity, optical texture, reactivity on thermobalance, CRI/CSR e DI150/15. The results achieved showed that the insertion of charcoal on fraction G compromised less the quality parameters of cokes with charcoal. Contents up to 3% of charcoal were tolerated for this particle size distribution while for fraction F, only 1%. Another point noticed was that the coke produced with charcoal addition had no significant drop on sulfur content, with the exception of the coke sample with 10% of charcoal and fraction G. In all samples with charcoal it was also possible to see an increase on surface area in relation to the reference coke. The dynamic thermogravimetric tests also provided relevant information regarding to the temperatures and apparent reaction rates of cokes made with charcoal.
258

Vývoj partnerských vztahů v současné době / The developement of partnerships in these days

URBANOVÁ, Simona January 2007 (has links)
This diploma thesis is used as a pilot study, which requires sensitive and private information. Data necessary for research have been hardly accessible. The own qualitative research has been done in form of half-standardized interviews, secondary analysis and case studies. There have been delimitated areas and specified main guideline questions, which were, if necessary, closely specified in the course of interview. The maximum length of an interview was 45 min. Respondents answered questions in anonymous way. 14 case studies have been developed based on obtained data.
259

Protótipo em escala piloto para produção de sulfato ferroso a partir de concentrado de pirita da mineração de carvão

Vigânico, Eunice Maria January 2014 (has links)
O presente trabalho teve como objetivo desenvolver um protótipo para a produção hidrometalúrgica de sulfato ferroso heptahidratado (FeSO4.7H2O – melanterita). A matéria prima foi um concentrado de pirita obtido a partir de rejeitos do beneficiamento de carvão mineral. Construiu-se, em escala piloto, uma planta de lixiviação com 300 kg de um concentrado com 73,2% de pirita. Nesta unidade, realizou-se uma etapa de lixiviação com água, em circuito fechado, sob condições aeróbias, com o intuito de se obter um extrato aquoso rico em íons férrico e sulfato. A seguir, procederam-se mudanças no sistema de forma a estabelecer uma condição anaeróbia ao meio, transformando os íons férricos em ferrosos. O lixiviado, rico em Fe2+, foi precipitado na forma de sulfato ferroso heptahidratado pela adição de etanol. Esse precipitado foi submetido a uma etapa de recristalização, obtendo-se cristais de melanterita de maior pureza. Ambos os produtos foram caracterizado por análise química elementar e difração de raios X. Os cristais de melanterita recristalizados apresentaram alta pureza, com qualidade para uso químico e farmacêutico. Assim, desenvolveu-se uma nova rota para produção de sulfato ferroso tendo como matéria-prima um concentrado de pirita da mineração de carvão (usualmente o sulfato ferroso é produzido como coproduto da produção de ilmenita e aço). A tecnologia apresenta uma elevada conversão do ferro lixiviado em melanterita e os insumos necessários são pirita, água e álcool etílico. A proposta abre uma nova possibilidade de uso dos rejeitos de carvão e a possibilidade de comercialização de outro produto na cadeia produtiva de carvão mineral. / The aim of this work was to develop a prototype for hydrometallurgical production of ferrous sulfate heptahydrate crystals (FeSO4.7H2O – melanterite). The raw material was a pyrite concentrate obtained from a coal tailing. The leaching system was assembled in pilot scale with 300 kg of a concentrate with 73.2% pyrite. Initially, it was carried out a leaching step in aerobic conditions with the purpose to obtain an aqueous solution rich in ferric ions and sulfate. Next, modifications were proceeded to establish an anaerobic condition in the reactor, converting the ferric to ferrous ions. Ethanol was added to the leaching solution to provide the precipitation of the Fe2+ and sulfate as ferrous sulfate heptahydrate. The ferrous sulfate precipitate was recrystallized, allowing producing melanterite crystals of higher purity. The crystals were characterized in terms of chemical and mineralogical composition. The process allowed producing crystals with a high purity attending chemical and pharmaceutical purposes. Thus, it was developed a process to produce ferrous sulfate from coal wastes (usually, ferrous sulfate crystals are produced as a co product from titanium dioxide and steel production). The technology presents a high conversion factor of soluble Fe2+ to melanterite and the necessary incomes are pyrite, water, and ethylic alcohol. The hydrometallurgical technique applied in this study allowed production of a commercial grade product from coal mining waste material.
260

Development of a Diffused Junction Silicon Solar Cell Pilot Line

January 2014 (has links)
abstract: In the interest of expediting future pilot line start-ups for solar cell research, the development of Arizona State University's student-led pilot line at the Solar Power Laboratory is discussed extensively within this work. Several experiments and characterization techniques used to formulate and optimize a series of processes for fabricating diffused-junction, screen-printed silicon solar cells are expounded upon. An experiment is conducted in which the thickness of a PECVD deposited anti-reflection coating (ARC) is varied across several samples and modeled as a function of deposition time. Using this statistical model in tandem with reflectance measurements for each sample, the ARC thickness is optimized to increase light trapping in the solar cells. A response surface model (RSM) experiment is conducted in which 3 process parameters are varied on the PECVD tool for the deposition of the ARCs on several samples. A contactless photoconductance decay (PCD) tool is used to measure the dark saturation currents of these samples. A statistical analysis is performed using JMP in which optimum deposition parameters are found. A separate experiment shows an increase in the passivation quality of the a-SiNx:H ARCs deposited on the solar cells made on the line using these optimum parameters. A RSM experiment is used to optimize the printing process for a particular silver paste in a similar fashion, the results of which are confirmed by analyzing the series resistance of subsequent cells fabricated on the line. An in-depth explanation of a more advanced analysis using JMP and PCD measurements on the passivation quality of 3 aluminum back-surface fields (BSF) is given. From this experiment, a comparison of the means is conducted in order to choose the most effective BSF paste for cells fabricated on the line. An experiment is conducted in parallel which confirms the results via Voc measurements. It is shown that in a period of 11 months, the pilot line went from producing a top cell efficiency of 11.5% to 17.6%. Many of these methods used for the development of this pilot line are equally applicable to other cell structures, and can easily be applied to other solar cell pilot lines. / Dissertation/Thesis / M.S. Electrical Engineering 2014

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