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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.
101

Correção o de PCR em processadores de fluxos de transporte MPEG-2

Avino, Heitor Judiss 25 September 2012 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T18:50:03Z No. of bitstreams: 1 Dissertação - Heitor Judiss Savino.pdf: 12604505 bytes, checksum: fb1bcd22abe6766240e85da3ba2e5109 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T19:37:30Z (GMT) No. of bitstreams: 1 Dissertação - Heitor Judiss Savino.pdf: 12604505 bytes, checksum: fb1bcd22abe6766240e85da3ba2e5109 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T19:37:54Z (GMT) No. of bitstreams: 1 Dissertação - Heitor Judiss Savino.pdf: 12604505 bytes, checksum: fb1bcd22abe6766240e85da3ba2e5109 (MD5) / Made available in DSpace on 2016-02-18T19:37:54Z (GMT). No. of bitstreams: 1 Dissertação - Heitor Judiss Savino.pdf: 12604505 bytes, checksum: fb1bcd22abe6766240e85da3ba2e5109 (MD5) Previous issue date: 2012-09-25 / Não informada / Currently, the MPEG-2 transport stream is widely used as multiplexing system for sending audio, video, and data, in digital television networks. The transmitted infor- mation is divided into xed-length pa kets, whi h are multiplexed in time and then sent to the re eiver. In order to ensure the orre t presentation of data related to a given program (e.g., audio and video), the transport stream an provide time bases, whi h are used for syn hronizing the re eption system. However, that information, whi h is known as Program Clo k Referen e (PCR) and is also periodi ally embedded in the multiplexed data stream, may su er from ina ura ies, due to the pro essing hain between transmitter and re eiver, whi h an be per eived in the form of jitter. In order to prevent that errors aused by the transport stream pro essing hain, whi h ompromises the proper presentation of the transmitted information, PCR orre tion methods are normally employed. This work presents a review of the PCR orre - tion methods ommonly used in the literature and introdu es two new ontributions. The rst one onsists of a shared a ess stru ture for the orre tion blo k, whi h has the potential to provide a redu ed omputational omplexity (in terms of arithmeti operations) and hardware requirements, when used with traditional PCR orre tion methods. The se ond one devises an intelligent method for PCR orre tion, whose main feature lies on the redu tion of the jitter aused by the orre tion pro ess. Its ar hite ture is based on the ooperative operation of the main modules involved in this pro ess: the rate adapter and the PCR orre tor. In spite of presenting a higher om- plexity, its superior performan e favors the syn hronization pro ess, performed by the re eiver, whi h makes it suitable for pre ise time-bases demanding systems. The pro- posed methodologies are ombined, whi h provides a omplete and e ient framework for pro essing MPEG-2 transport streams. / Atualmente, o fluxo de transporte MPEG-2 é amplamente utilizado como chamada de transporte para a multiplexação de programas que arregam áudio, vídeo e dados, em redes de televisão digital. As informações transmitidas são divididas em pa otes de tamanho xo, multiplexadas no tempo e então enviadas ao re eptor. Para que os da- dos de um mesmo programa sejam apresentados orretamente e em sin ronismo (e.g. áudio e vídeo), o uxo de transporte permite a in orporação de bases de tempo, que são utilizadas na sin ronização do sistema de re epção. Entretanto, essa informação, onhe ida omo Program Clo k Referen e (PCR) e inserida periodi amente no feixe multiplexado, pode sofrer erros, observados na forma de jitter, devido à adeia de pro- essamento entre transmissor e re eptor. Dessa forma, para se evitar que o erro inserido pelo pro essamento do uxo de transporte prejudique a apresentação da informação enviada, métodos de orreção de PCR são geralmente utilizados. Este trabalho apre- senta um estudo sobre os métodos de orreção de PCR mais utilizados na literatura e introduz duas novas ontribuições. A primeira onsiste em uma estrutura de a esso ompartilhado para o blo o de orreção, que tem o poten ial de propor ionar ara terís- ti as reduzidas de omplexidade omputa ional (quantidade de operações aritméti as) e requisitos de hardware, quando utilizada em onjunto om métodos tradi ionais de orreção de PCR. A segunda onsiste em um método inteligente para a orreção de PCR, uja prin ipal ara terísti a é a redução do erro inserido pelo pro esso de orre- ção. A sua arquitetura é baseada na operação ooperativa dos dois prin ipais agentes envolvidos nesse pro esso: os módulos de adaptação de taxa e de orreção de PCR. Apesar de apresentar maior omplexidade omputa ional, o seu desempenho superior fa ilita o pro esso de sin ronização, exe utado pelo re eptor, o que o torna bastante adequado a sistemas que exigem bases de tempo pre isas. As metodologias propostas são utilizadas em onjunto, propor ionando um esquema integrado e e iente para o pro essamento de uxos de transporte MPEG-2.
102

[en] THE INTEGRATION OF ERGONOMIC REQUIREMENTS AT SHOES INDUSTRY: A MODEL TO INCREASE THE HEALTHINESS OF PEOPLE WITH DIABETIC FEET / [pt] A INCORPORAÇÃO DE REQUISITOS ERGONÔMICOS NA INDÚSTRIA CALÇADISTA: UM MODELO EM PROL DA SAÚDE DOS DIABÉTICOS

ROSA LIDICE DE MORAES VALIM 06 October 2006 (has links)
[pt] Esta dissertação apresenta os resultados de pesquisa sobre um modelo para incorporação de requisitos ergonômicos na indústria calçadista em prol da saúde dos diabéticos. Pretende-se que o modelo aqui apresentado beneficie, por extensão, a pacientes atingidos por outras patologias que também geram problemas neuropáticos e vasculares periféricos (pacientes com problemas renais, hipertensos, indivíduos afetados por complicações decorrentes do tabagismo, etc). Através de entrevistas semi-estruturadas, formulários e questionários foram obtidas informações junto diferentes grupos envolvidos diretamente com a problemática do Pé Diabético. A análise destes dados demonstrou que grande parte dos modelos de calçados, encontrados nas lojas do Rio de Janeiro, propicia traumas repetitivos aos pés de pessoas com problemas de neuropatia diabética sensitiva nos pés (ou sensibilidade comprometida nos pés por causa do diabetes, que ocorre quando as células nervosas da região deixam de conduzir as informações relativas aos estímulos sensitivos da forma adequada) devido a problemas de projetação/design (palmilha mal projetada, costuras internas salientes ou solados duros demais). E, uma vez que diabéticos tendem a ter lenta cicatrização em virtude de deficiente circulação periférica gerada pela doença, qualquer ferida torna-se mais do que um simples problema passageiro, torna-se um perigo real à saúde. Este estudo revelou-se interdisciplinar, na medida em que seu campo permeou outras áreas do saber para conjugar informações relacionadas à problemática do Pé Diabético. Trabalhou-se aqui com o seguinte problema: diabéticos são prejudicados pela maioria dos calçados produzidos para o mercado brasileiro, que não levam em consideração questões ergonômicas, físicas, ou mesmo cognitivas relacionadas ao diabetes no momento de sua produção. / [en] This dissertation presents the results of a research that lead to a theoretical model proposing the integration of ergonomic requirements at shoes´ industry in order to increase the healthiness of people with diabetic feet. It´s expected that the model here presented benefits, by extension, also patients injured by other pathologies that causes neuropathycs or vascular peripheryc problems: patients with kidney problems, hypertensives, people affected by complications caused by tobacco addiction, etc. Formularies, questionnaires, and semi structured interviews supported the data collection that was done. Different groups were interviewed, all of them directed related with the diabetic feet problem. The data analysis presented evidences that most part of the shoes available in Rio de Janeiro might be able to cause repetitive traumas to neuropathyc feet of diabetic problem (lack of sensibility at the feet, because of the diabetes, happens when nervous stop conducting information related to sensitive stimulation in a healthy way), because of projetation/design (midsoles not well developed, thick internal sews or too hard outsoles). And, once diabetics are predisposed to have deficient peripheryc circulation any wound might become more then just a simple problem, might become a real danger. The study here presented reassured its interdisciplinaryti once extended its exploratory field to other areas with the purpose of merging related information regarding diabetic feet. The following problem guided this research: Diabetics are damaged by most part of the shoes produced for the internal market, because they don´t take in consideration ergonomic, cognitive or physical issues regarding diabetes during production.
103

Possibilities and Limitations of using Production Waste PET and PES materials in Additive Manufacturing (3D Printing Technology)

Gopathi, Pranay, Surve, Pratik January 2017 (has links)
No description available.
104

Kinetics and Reaction Mechanisms for Methylidyne Radical Reactions with Small Hydrocarbons

Ribeiro, Joao Marcelo Lamim 07 November 2016 (has links)
The chemical evolution with respect to time of complex macroscopic mixtures such as interstellar clouds and Titan’s atmosphere is governed via a mutual competition between thousands of simultaneous processes, including thousands of chemical reactions. Chemical kinetic modeling, which attempts to understand their macroscopic observables as well as their overall reaction mechanism through a detailed understanding of their microscopic reactions and processes, thus require thousands of rate coefficients and product distributions. At present, however, just a small fraction of these have been well-studied and measured; in addition, at the relevant low temperatures, such information becomes even more scarce. Due to the recent developments in both theoretical kinetics as well as in ab initio electronic structure calculations, it is now possible to predict accurate reaction rate coefficients and product distributions from first-principles at various temperatures, often in less time, than through the running of an experiment. Here, the results of a first principles theoretical investigation into both the reaction rate coefficients as well as the final product distributions for the reactions between the ground state CH radical (X2Π) and various C1-C3 hydrocarbons is presented; together, these constitute a set of reactions important to modeling efforts relevant to mixtures such as interstellar clouds and Titan’s atmosphere.
105

Toughening of highly crosslinked epoxy resin systems

Stein, Jasmin January 2013 (has links)
Highly crosslinked epoxy resin systems are essential in aerospace applications due to the high operating temperatures. Although highly crosslinked epoxy resins have the required glass transition temperature (Tg) for the application, they are inherently brittle and matrix toughness is improved by incorporation of a second phase. Previous studies have focused mostly on toughening of lightly crosslinked epoxy systems, whereas this study investigates toughening of a highly crosslinked epoxy resin system using thermoplastic toughners poly(ether sulfone) (PES) and a poly(methyl methacrylate)-b- poly(butyl acrylate)-b-poly(methyl methacrylate) (MAM) block copolymer (BCP).
106

Estudo da distribuição da pressão plantar e do equilibrio corporal em corredores de longa distancia / Study of plantar pressure distribution and body balance in long distance runners

Schmidt, Ademir 17 October 2006 (has links)
Orientador: Antonia Dalla Pria Bankoff / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica / Made available in DSpace on 2018-08-08T02:53:42Z (GMT). No. of bitstreams: 1 Schmidt_Ademir_D.pdf: 56451276 bytes, checksum: 5b096a2973998a3ce6ed8b83c8ddc707 (MD5) Previous issue date: 2006 / Resumo: As corridas de longa distância, sejam de caráter competitivo ou de promoção da saúde, geram cargas compressivas consideráveis no sistema locomotor. Essas cargas, se não adequadamente distribuídas, predispõem os praticantes a lesões crônicas e agudas. Nesse sentido, o objetivo desta pesquisa foi estudar a distribuição da pressão plantar e do equilíbrio corporal em corredores de longa distância. Participaram do estudo 17 corredores de longa distância do sexo masculino com idade X = 28,5 :t 9,5 anos, peso X = 63,6 :t 6,9 Kg e altura X = 173,5 :t 7,0 cm. A seleção dos sujeitos foi feita segundo critérios de acessibilidade. Para o estudo da distribuição da pressão plantar e do equiHbrio corporal, foi utilizado um baropodômetro eletrônico para realizar uma análise estática, dinâmica (andando e correndo) e uma análise estabilométrica. Os três testes foram realizados com os corredores inicialmente descalços e posteriormente utilizando seu tênis de corrida. Além da análise baropodométrica, os sujeitos responderam um questionário contendo 23 perguntas sobre sua rotina de treino, índice de lesões sofridas, distância percorrida semanalmente, dentre outras. Na análise estatística utilizou-se o teste paramétrico t-Student para grupos independentes. Os resultados da análise baropodométrica estática dos corredores demonstraram distribuição assimétrica da carga entre os membros inferiores, com maior carga direcionada para a parte anterior do pé direito. A distribuição da pressão plantar revelou maior carga na parte anterior do pé esquerdo nos testes dinâmicos com os corredores descalços, enquanto que nos testes com o calçado esportivo não foram detectadas diferenças significantes. Foi constatado que os corredores avaliados realizam o contato pé-solo predominantemente com a parte anterior do pé. O uso do calçado esportivo não apresentou nenhuma interferência específica nos testes realizados. A oscilação do centro de pressão foi maior nos testes monopodálicos. O estudo do equilíbrio corporal demonstrou significativa dependência do sistema visual e tendência de maior oscilação do centro de pressão no eixo X / Abstract: Long distance running as a competitive way or even to promote health produces considerable compressive load on the locomotor system. If this load is not properly distributed, it makes practitioners prone to chronic and acute injuries. Therefore, the purpose of this research was to study the plantar pressure distribution and body balance in long distance runners. In total 17 male long distance runners were considered for this study with age X = 28.5 :t 9.5, weight X = 63.6 :t 6.9 kg and height X = 173.5 :t 7.0 cm. The selection of individuaIs was done by following accessibility criteria. To perform the study ofthe plantar pressure distribution and body balance an electronic baropodometer was used. The baropodometric tests comprised a static, a dynamic (walking and running) and a stabilometric analysis. All tests were performed initially barefoot and afterwards with the runners wearing their running shoes. The individuaIs also responded to a 23 question survey about their practice routine, injury incidence, distance performed during the week and so forth. A parametric t-Student test for independent groups was used for the statistic analysis. The results of the static baropodometric analysis showed asymmetric pressure distribution between the lower extremities, with greater pressure directed to the right forefoot. The plantar pressure distribution reveled grater load directed to the left forefoot in the dynamic tests performed with the sport running shoes, meanwhile no significant differences were detected in the barefoot tests. The results also demonstrated that the runners evaluated in this study were predominantly forefoot strikers. The running shoes did not show any specific influence on the tests results. Oscillation of the center of pressure was greater in the unilateral tests. The body balance study revealed significant visual system dependence and a tendency of greater oscillations ofthe center ofpressure on the X-axis / Doutorado / Ciencia do Desporto / Doutor em Educação Física
107

Understanding interfaces in thin-film solar cells using photo electron spectroscopy. : Effect of post-deposition treatment on composition of the solar cell absorber.

Hansson, Henrik January 2019 (has links)
The increasing demand of renewable energy is the big driving force for the research and development of more efficient solar energy conversion solutions. Solar cells, which use the photovoltaic effect to convert the photon energy to electrical current, are an important solar energy conversion technique. One solar cell technology is thin-film solar cells. Thin-film solar cells use an absorption layer with a direct band gap. A direct band gap has the advantage that the photons will penetrate less deep until a photoexcitation occur compared to semiconductors with an indirect band gap (e.g. silicon). For this reason the thin-film solar cells can be made very thin.CIGS is a common thin-film solar cell absorber material containing copper (Cu), indium (In), gallium (Ga) and selenium (Se). One objective of this work has been to determine element concentrations of CIGS absorption layers from sample measurements. The GGI ratio determines the band gap, which is an important factor for optimising the efficiency of the solar cell.1 The copper vacancy is the main acceptor dopant in CIGS. The Cu concentration has shown to be important for the efficiency and for other properties of the absorber [2].The measuring technique used in this work has been photoelectron spectroscopy (PES). PES produces a spectrum showing distinct peaks corresponding to electron binding energy levels for specific element subshells. Measurements with different photon energies have been performed on samples with and without post deposition treatment (PDT). A great deal of the effort has been to calculate relative element concentrations based on the PES peak intensities. Two important parameters when performing the calculations are the photoionization cross section (including the angular dependence of the cross section) and the inelastic mean free path of the photoelectrons.The results show that the GGI and the corresponding band gap will be almost the same with and without PDT except for close to the surface where PDT lowers the GGI.The calculations showed that the copper concentration is lowest at the surface. Moreover, PDT with RbF results in lower copper concentration closer to the junction.The results show a discrepancy of the GGI and CGI ratios when using the angular dependent cross sections in [10] and [11] compared to using the cross sections in [6] and [7]. / Det ökande behovet av förnybar energi gör att forskning och utveckling av solenergilösningar är av största vikt. Solceller, vilka utnyttjar den fotovoltaiska effekten, är den vanligaste tekniken för omvandling av solenergi till elektricitet. Tunnfilmssolceller är en typ av solceller vars absorbent har ett direkt bandgap, till skillnad från kisel som har ett indirekt bandgap. Fördelen med ett direkt bandgap är att det ljusabsorberande materialet kan göras mycket tunt.En vanlig tunnfilmssolcell är CIGS. Det är en komposit bestående av koppar (Cu), indium (In), gallium (Ga) och selen (Se). Ett syfte med detta självständiga arbete har varit att beräkna koncentrationerna av de ingående ämnena i halvledarskiktet av CIGS. GGI-kvoten bestämmer bandgapet, vilket är en viktig faktor för solcellens verkningsgrad. Kopparvakansen är den huvudsakliga halvledaracceptorn i CIGS. Kopparkoncentrationen har visat sig vara viktig för bl.a. solcellens verkningsgrad [2].Mättekniken som används i detta arbete kallas fotoelektronspektroskopi (PES). PES-mätningar ger ett spektrum där spektrallinjerna representerar olika nivåer av elektroners bindningsenergi för olika grundämnen. Mätningar med olika fotonenergier, på prover med och utan ytbehandling (PDT), har utförts. En stor del av arbetet har varit att beräkna relativa koncentrationer av de olika grundämnena från spektrallinjerna i spektrumet. Viktiga parametrar som man behöver ta hänsyn till i uträkningarna är sannolikheten för en fotoemissionsprocess hos fotonerna, vinkelberoendet och den fria medelväglängden hos fotoelektronerna.Resultaten visar att GGI-kvot och bandgap blir nästan detsamma med eller utan PDT, förutom närmast ytan där PDT minskar GGI-kvoten.Resultaten visar också att kopparkoncentrationen är lägst på ytan och att PDT med RbF minskar kopparkoncentrationen närmast ytan.Resultaten visar att det blir skillnader mellan GGI- och CGI-kvoterna beroende på om beräkningarna baserats på vinkelberoende träffytor enligt [10] och [11] eller baserats på träffytor enligt [6] och [7].
108

Pes ve veřejném prostoru / Dog in a public space. Negotiating "more than human" public space

Baños Pittnerová, Daniela January 2015 (has links)
The thesis deals with the presence of a dog in the city, specifically in the public space and the research itself is aimed at negotiating "more than human" public space. The presence of animals in the human world causes conflicts about the "right" place of this animal, whether is place conceptual or physical. The work takes the form of a case study, where I chose for research borough of Prague 2 and on particular cases of negotiation, I watched how each party tries to affect a form of public space. Through qualitative analysis I uncover the key points of negotiation by which I learn how the different parties understand the presence of a dog in a public space, on what basis is constantly negotiates form of residence and movement of the dog in this specific area. I have used several techniques of qualitative research, especially analysis of available documents, semi-structured interviews and participant observation. Data was analyzed using open coding. In the end the thesis answers to research questions, formulate recommendations and open debate.
109

Referenční význam slov při komunikaci člověka a psa / Reference meaning of words in human-dog communication

Stemmerová, Lucia January 2018 (has links)
In recent twenty years dogs have become model subjects of comparing studies. These experiments show us that specific cognitive skills have developed during their domestication as an adaptation to anthropomorphic environment. For example dogs can follow human gaze and understand gestures. An important topic of today researches are linguistic skills of dogs. Knowledge from this area would help to discover more from evolution processes which formed human language. Last studies have proven dogs can distinguish a new object by a fast mapping. But when distinguishing two new objects, dogs had problems. That is why I decided to verify if dogs are able to remember two new words and match them with correct objects during one session. For this experiment I worked on a new methodical procedure and used three border collies dogs. The results showed that after some training dogs were able to correctly distinguish two new words in case the experimentalist stood in front of them and they used multisenzorial perception. In case they had only one communication source (visual or acoustic), they made more mistakes. The results show that functional reactions of dogs to human vocalization are getting better if they can use visual and acoustic source in one time during an interspecies communication. Key words: dog,...
110

Dobrovolník - předvychovatel v České republice a Spojených státech amerických / A Volunteer - Puppy Raiser in the Czech Republich and the United States of America

Luksa, Linda January 2020 (has links)
This master thesis introduces a form of volunteering which is not well known to the public, so-called puppy raising of guide dogs for the visually impaired. This phenomenon is introduced on the background of a comparison of two civil society service organizations, one based in the Czech Republic and the other in the United States of America. These organizations both come from a different type of civil society but have many similarities as well. At the end of this thesis, the results found through qualitative research are presented, where these data were gained through interviews, documents, but also by participatory observation directly in the respective organizations.

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