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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.
151

Efeitos do laser de baixa intensidade em780nm sobre a performance muscular aeróbica de ratos em treinamento físico em esteira. / Effects of Low Power Laser in 780ηm on muscler aerobic performance of rats on training treadmill.

Vieira, Wouber Hérickson de Brito 14 December 2004 (has links)
Made available in DSpace on 2016-06-02T20:19:20Z (GMT). No. of bitstreams: 1 DissWHBV.pdf: 1262408 bytes, checksum: 46ed12e3f59bfa6a851e19038a1181ec (MD5) Previous issue date: 2004-12-14 / Universidade Federal de Sao Carlos / The purpose of this study was to evaluate relative the physiological adaptation the activities of enzymes Lactate Dehidrogenase LDH (glycolytic) e Citrate Synthase CS (oxidative) and to the Anaerobic Threshold (AT), to the exercise in treadmill in rats submitted to the photostimulation for low-intensity laser (780 ηm) in the main participant muscles of the march. Fifty-four male Wistar rats had been part of the study. These animals were divided in four groups: Two had remained in rest (1) GRC, being one of them irradied (2) GRL, and other two were submitted to an aerobic treadmill training program during 5 weeks and to a multistage treadmill test of increasing intensity (3) GEC, being one of them irradied (4) GEL. The irradiation for infra-red laser (780 ηm) was made daily in number of four (quadriceps, maximum glúteo, soleus, tibialis anterior) in each back leg of the animals, totalizing 8 applications for animal/day, using (dose, 3,8 J/cm2; power, 15 mW; time, 10 s, continuous) during 5 weeks consecutives. The multistage treadmill tests of increasing intensity were made once a week totalizing 5 evaluation, in order to obtain blood samples for determination of the AT. In the analyses electrophoretics and spectrophotometic of the LDH and CS muscles samples (soleus, TA and cardiac) were removed 48 hours after the last exercise bout. The laser to promote increase in the oxidative metabolism of 2% a 78%, the exercise of 18% a 75%, and action combined of 43% a 92%; Apparent systemic action of the laser was detected in cardiac muscle with increase in the activity of the CS and reduction of the LDH. The group GEC and GEL showed increase in the maximum speed, in the speed corresponding to the AT and a trend reduction of the blood lactate concentration during the training period. However, no significant difference occurred between two groups though the GEL had shown higher values. These data suggest that the aerobic treadmill-training partner to the low-intensity laser can to promote physiological adaptation in the direction of increase oxidative capacity in the animals, represented by increase of the CS, reduction of the LDH and by the higher degree of effort to reach the Anaerobic Threshold. This similarity has a utility therapeutic practical. / O presente estudo avaliou as adaptações fisiológicas relativas as atividades das enzimas Lactato Desidrogenase - LDH (glicolítica) e Citrato Sintase - CS (oxidativa) e ao Limiar de Anaerobiose (LA), ao exercício em esteira em ratos submetidos à fotoestimulação por laser de baixa intensidade (780nm) nos principais músculos participantes da marcha. Fizeram parte do estudo 54 ratos machos, jovens (30 dias), Wistar, que foram divididos em quatro grupos: dois permaneceram em repouso: (1) GRC, sendo um deles irradiado (2) GRL, e dois foram submetidos a um protocolo de treinamento aeróbio em esteira por 5 semanas e a testes de esforços crescentes (3) GEC, sendo um deles irradiado (4) GEL. A irradiação por laser infravermelho foi feita, diariamente, em número de quatro: quadríceps, glúteo máximo, Tibial Anterior (TA) e sóleo, em cada pata traseira, totalizando 8 aplicações por animal/dia, sob os parâmetros: Dose: 3,8 J/cm2, Potência: 15 mW, Tempo: 10 segundos, modo contínuo, durante 5 semanas consecutivas. Os testes de esforço crescente foram realizados, uma vez por semana, totalizando 5 avaliações durante as quais foram obtidas amostras de sangue visando a determinação do LA. Nas análises eletroforéticas e espectrofotométricas da LDH e CS, foram utilizadas frações de músculo TA, sóleo e cardíaco retiradas 48 horas após a última sessão de exercício. O laser provocou aumentos do metabolismo aeróbio de 2% à 78%, o exercício de 18% à 75% e suas ações combinadas de 43% à 92%. Aparente ação sistêmica do laser foi detectada em músculo cardíaco, com aumento da atividade da CS e diminuição da atividade LDH. Os grupos GEC e GEL exibiram aumento na velocidade máxima, LA deslocado para um nível de maior esforço e uma ligeira tendência de redução do lactato sérico no decorrer das avaliações. Entretanto, não houve diferenças estatisticamente significantes entre os grupos, apesar do GEL ter exibido maiores valores. Esses dados sugerem que o treinamento aeróbio em esteira associado ao laser de baixa intensidade possa acarretar adaptações fisiológicas no sentido de aumento na capacidade oxidativa dos animais representada pelo aumento na atividade da CS, diminuição da LDH e maior grau de esforço para a obtenção do LA, fato este, de grande utilidade na prática terapêutica.
152

Determina??o de CD, PB, e TL em ?gua produzida por HR-CS GF AAS ap?s extra??o em ponto nuvem / Determination of Cd, Pb, and Tl produced water by HR-CS GF AAS after extraction point in cloud

Bezerra, Breno Gustavo Porf?rio 03 November 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-26T17:52:57Z No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-28T19:06:56Z (GMT) No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) / Made available in DSpace on 2016-01-28T19:06:56Z (GMT). No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) Previous issue date: 2014-11-03 / A ?gua produzida representa um grande problema associado com a atividade de extra??o de ?leo bruto. O monitoramento dos n?veis de metais nos res?duos ? constante e requer a utiliza??o de t?cnicas anal?ticas sens?veis. No entanto, a determina??o de elementos tra?o muitas vezes pode exigir uma etapa de pr?-concentra??o. O objetivo deste trabalho foi desenvolver um m?todo anal?tico simples e r?pido para a extra??o e pr?-concentra??o baseada no fen?meno de extra??o no ponto nuvem para a determina??o do Cd, Pb e Tl em ?gua produzida amostras por Espectrometria de Absor??o de alta resolu??o com fonte continua e atomiza??o em forno de grafite. Um planejamento Box Behnken foi usado para obter a condi??o ideal de extra??o dos analitos. Os fatores avaliados foram: concentra??o do agente complexante (o,odietilditilfosfato am?nio, DDTP), a concentra??o do ?cido clor?drico e concentra??o do surfactante (Triton X -114). A condi??o ideal de extra??o foi obtida com: 0,6% m v -1 DDTP, HCl 0,3 mol L-1 e 0,2% m v -1 de Triton X - 114 para o Pb; 0,7% m v -1 DDTP, HCl 0,8 mol L-1 e 0,2% m v -1 Triton X-114 para Cd. Para o Tl foi evidenciado que melhor condi??o de extra??o se d? com aus?ncia de DDTP, as condi??es de extra??o foram ent?o HCl 1,0 mol L-1 e 1,0% m v -1 de Triton X - 114. Os limites de detec??o para o m?todo proposto, foram 0,02 ?g L-1 , 0,004 ?g L-1 e 0,06 ?g L-1 para o Pb, Cd e Tl, respectivamente. Os fatores de enriquecimento foram superiores a 10 vezes. O m?todo foi aplicado para a ?gua produzida da bacia Potiguar, e testes de adi??o e recupera??o foram realizados, e valores ficaram entre 81% e 120%. A precis?o foi expressa com desvio padr?o relativo (RSD) foi inferior a 5% / Produced water is a major problem associated with the crude oil extraction activity. The monitoring of the levels of metals in the waste is constant and requires the use of sensitive analytical techniques. However, the determination of trace elements can often require a pre-concentration step. The objective of this study was to develop a simple and rapid analytical method for the extraction and pre-concentration based on extraction phenomenon cloud point for the determination of Cd, Pb and Tl in produced water samples by spectrometry of high resolution Absorption source continues and atomization graphite furnace. The Box Behnken design was used to obtain the optimal condition of extraction of analytes. The factors were evaluated: concentration of complexing agent (o,o-dietilditilfosfato ammonium, DDTP), the concentration of hydrochloric acid and concentration of surfactant (Triton X -114). The optimal condition obtained through extraction was: 0,6% m v-1 DDTP, HCl 0,3 mol L-1 and 0,2% m v-1 of Triton X - 114 for Pb; 0,7% m v-1 DDTP, HCl 0,8 mol L-1 and 0,2% m v-1 Triton X-114 for Cd. For Tl was evidenced that best extraction condition occurs with no DDTP, the extraction conditions were HCl 1,0 mol L-1 e 1,0% m v-1 de Triton X - 114. The limits of detection for the proposed method were 0,005 ?g L-1 , 0,03 ?g L-1 and 0,09 ?g L-1 to Cd, Pb and Tl, Respectively. Enrichment factors Were greater than 10 times. The method was applied to the water produced in the Potiguar basin, and addition and recovery tests were performed, and values were between 81% and 120%. The precision was expressed with relative standard deviation (RSD) is less than 5%
153

Desenvolvimento de métodos analíticos para a determinação de metais traço em vegetais da família Solanaceae por espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos.

Siqueira, Marianna Pozzatti Martins de January 2017 (has links)
Neste trabalho foram desenvolvidos quatro métodos analíticos para a determinação de cádmio, cromo, cobre, níquel e ferro em vegetais da família Solanaceae, cultivados pelos métodos convencional e orgânico de produção, obtidos em feiras e mercados da cidade de Porto Alegre, Brasil. Estes vegetais são muito consumidos devido a grande quantidade de nutrientes, no entanto, podem ser contaminados por elementos potencialmente tóxicos, por meio da exposição a poluição, uso de pesticidas, fertilizantes e água contaminada. As determinações foram conduzidas pela técnica de espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos. Para Cd, Cr e Cu foram desenvolvidos três métodos independentes. No caso da determinação de Ni e Fe foi realizada análise simultânea, empregando linhas analíticas alternativas. Temperaturas de pirólise e atomização foram otimizadas para todos os elementos analisados, visando sinais analíticos com elevada sensibilidade e livres de interferências. Os métodos otimizados foram aplicados em amostras de pimentão, batata, tomate, berinjela, pimenta e physalis. Várias amostras apresentaram concentrações superiores aos limites máximos estabelecidos por legislações específicas. Os métodos propostos envolveram mínimo preparo de amostra, reduzindo riscos de contaminação, tempo analítico e custos, além de demonstrarem-se simples, precisos, rápidos e sensíveis. / In this work, four methods have been developed for the determination of cadmium, chromium, copper, nickel and iron in vegetables of the Solanaceae family, cultivated in conventional and organic farming systems, obtained from local markets and local farms, located in the city of Porto Alegre, Brazil. These vegetables are much appreciate due to the large amount of nutrients present in it. However, vegetables can be contaminated by potentially toxic elements, through the exposure to pollution, use of pesticide, fertilizers and contaminated water. The assays were carried out using a high-resolution continuum source graphite furnace atomic absorption spectrometer and direct solid sample analysis. Cd, Cr and Cu had their methods individually developed. In the case of the determination of Ni and Fe, it was applied simultaneous analysis, employing alternative analytical lines. Pyrolysis and atomization temperatures were optimized for all target elements, aiming for analytical signals with high sensitivity and free from interferences. The optimized methods were applied in samples of bell peppers, potato, tomato, eggplant, pepper and physalis. Several samples presented concentrations above the maximum permitted by specific legislation. The proposed methods were accurate, simple, fast and sensitive; moreover, a minimum sample preparation was necessary, reducing contamination, analytical time and costs.
154

Reoxigenação superficial da água em canais abertos: o efeito da recirculação produzida por bombeamento / Surface reoxygenation of water in open channels: the effect of pumping produced recirculation

Hemerson Donizete Pinheiro 26 August 2011 (has links)
O coeficiente de reaeração constitui-se no principal parâmetro usado em modelos de qualidade na avaliação preventiva do efeito da descarga de resíduos orgânicos sobre a concentração do oxigênio dissolvido (OD) em cursos de água naturais. Na literatura os valores observados para a concentração de saturação de OD em procedimentos experimentais para a determinação das taxas de reaeração superficial são, geralmente, reportados como inferiores aos valores calculados para as condições de temperatura, salinidade e pressão em que os experimentos foram realizados. Esse fato interfere significativamente na determinação do coeficiente de reaeração superficial, K2. Avalia-se neste trabalho a hipótese de que nessas situações a água é exposta a uma fonte de OD, que é a superfície em contato com a atmosfera, mas também a um sumidouro de OD, criado pelo próprio sistema de movimentação do fluido. O modelo matemático amplamente utilizado para estes fins não considera essa última possibilidade. Neste estudo foi comparada a eficácia deste modelo com um que considera a existência sumidouros do OD, o que justifica a baixa estimativa da concentração de saturação deste gás. Observou-se uma forte correlação entre a pressão na linha de sucção do sistema de recirculação e o valor do coeficiente de desoxigenação K*3 , que quantifica a intensidade do sumidouro. / The reaeration coefficient constitutes the main parameter used in models for the quality assessment of the preventive effect of the discharge of organic wastes on the concentration of dissolved oxygen (DO) in natural waterways. In the literature the values observed for the saturation concentration of DO in experimental procedures for determining the surface reaeration rates are generally reported as lower than the values calculated for the conditions of temperature, salinity and pressure at which the experiments were performed. This interferes significantly in the determination of surface reaeration coefficient, K2. In this work the following hypothesis is evaluated: that in these situations the water is exposed to a source of DO, which is the surface in contact with the atmosphere, as well as an DO sink, created by the pumping system. The mathematical model widely used does not consider this possibility. In this study the two kind of models were compared and the reasons for divergence were looked upon. There was a strong correlation between the pressure drop in the suction line of the recirculation system and a pseudo-coefficient of deoxygenation K*3 , which quantifies the sink intensity.
155

Analog and Digital Approaches to UWB Narrowband Interference Cancellation

Omid, Abedi January 2012 (has links)
Ultra wide band (UWB) is an extremely promising wireless technology for researchers and industrials. One of the most interesting is its high data rate and fading robustness due to selective frequency fading. However, beside such advantages, UWB system performance is highly affected by existing narrowband interference (NBI), undesired UWB signals and tone/multi-tone noises. For this reason, research about NBI cancellation is still a challenge to improve the system performance vs. receiver complexity, power consumption, linearity, etc. In this work, the two major receiver sections, i.e., analog (radiofrequency or RF) and digital (digital signal processing or DSP), were considered and new techniques proposed to reduce circuit complexity and power consumption, while improving signal parameters. In the RF section, different multiband UWB low-noise amplifier key design parameters were investigated like circuit configuration, input matching and desired/undesired frequency band filtering, highlighting the most suitable filtering package for efficient UWB NBI cancellation. In the DSP section, due to pulse transmitter signals, different issues like modulation type and level, pulse variety, shape and color noise/tone noise assumptions, were addressed for efficient NBI cancelation. A comparison was performed in terms of bit-error rate, signal-to-interference ratio, signal-to-noise ratio, and channel capacity to highlight the most suitable parameters for efficient DSP design. The optimum number of filters that allows the filter bandwidth to be reduced by following the required low sampling rate and thus improving the system bit error rate was also investigated.
156

Koncepční návrh výkonného kluzáku s pomocným elektrickým pohonem (dle EASA CS-22) / Conceptual design of high performance glider with electric propulsion (in complience with EASA CS-22)

Hlůšek, Josef January 2019 (has links)
This master's thesis is focused on conceptual design of glider with electric propulsion system following the CS-22 regulation. Statistical analysis of the glider with an auxiliary electric engine has been carried out in order to determine basic design parameters for conceptual design. Based on analytical drag polar, the flight performance parameters are calculated, in particular flight range and influence of the solar panels on the flight range. This thesis also includes preliminary design solution of accumulator placement within the wing.
157

Návrh letounu pro vlekání a základní akrobacii / Design of a aircraft for towing and basic acrobtics

Loutocký, Jiří January 2010 (has links)
This master thesis solves conceptual design of aerotow airplane and airplane for basic aerobatics. Airplane is designed by using of specification CS-23. The first part of the thesis solves conceptual design. Especially possible concepts and choice the best one according to requests. Next part deals with flight performance of aerotow airplane in normal flight and also in aerobatics. The third part is engaged in main flight performance in aerotow. 3D system model of whole aircraft and compact disk with mentioned 3D model and electronic version of thesis is also added.
158

Modifikace VOP letounu VUT100 / Modification of Horizontal Tail of VUT100 aircraft

Janhuba, Luboš January 2011 (has links)
The goal of the submitted Diploma Thesis is the Proposal of modifications of the horizontal tail (HT) of the plane VUT 100 by increasing the shoulder of HT and reduce of the HT surface. The Diploma Thesis consists of assessing the benefits of position adjustments, load calculation and the proposal of the basic design.
159

Jednomotorový víceúčelový dopravní letoun v kategorii CS/FAR 23 / Single-engined multipurpose transport aeroplane by the CS/FAR 23 category

Fiala, Luboš January 2013 (has links)
Thesis deals with design of a single-engine aircraft. The purpose of this aircraft design is to carry up nine passengers. The work outlines technical solution of several structural elements. The design starts with aerodynamic calculations, mass analysis and concludes with calculation of flight performance and development cost estimation.
160

Success factors in an introductory programming course in a non-CS major

Alnervik, Tilda, Ma, Gerui January 2020 (has links)
Purpose – The contradiction of the increased demand for IT specialists and the decrease of the enrollment in programming courses at universities worldwide has been discussed over the years. To tackle the problem, researchers and teachers in computing education have investigated various success factors in introductory programming courses, mostly within the context of computer science. This paper focuses on the investigation of success factors for students that are not majoring in computer science (non-CS) in an introductory programming course, to report on the results of student's performance and analysis of the most relevant success factors, also provide suggestions that could be considered for the course design and teaching method.   Method – The methods used to carry out the study are a survey with 36 participants, conducted before the start of an introductory programming course, and qualitative interviews conducted with twelve students after the end of the course. The interviews were then analysed thematically to find common patterns for five success factors between the students with different grades. The success factors that were examined are math background, previous programming experience, comfort level, motivation and attribution to success.   Findings – Math background could not be proved as a success factor in this study due to the lack of a standardized assessment of the students’ math levels. Previous programming experience could be regarded as a success factor but not as dominant as the success factor motivation, which has shown clear patterns in the data. Comfort level could be seen as one of the success factors as well, as most of the data in this study support this conclusion. Lastly, attribution to success as a success factor could not be supported by this study; the qualitative data showed variety which makes it hard to draw a conclusion directly.   Implications – The study suggest increasing the motivation for the non-CS students in introductory programming by combining programming with other subjects in the programme. The lecturer could customize the course for students with different interests so they could select a path and adapt the knowledge to their needs. Bridging courses and various forms of mentoring are also recommended to offer.   Limitations – The time frame of the study limited the amount of data that could be collected. The study was conducted with students from only one university and one non-CS programme, with a small data sample for analysis, which is limiting in the way the results can be generalized.

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