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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.
551

Avaliação metrológica da incerteza na medição de vazão mássica de gases com tecnologias volumétrica e pressão diferencial

MELO, FLAVIO B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:11Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:02Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
552

Avaliação da influência de diferentes tióis no desempenho de biossensores magnetielásticos para detecção de escherichia coli

Pozza, Márcia Dalla 12 December 2016 (has links)
Os métodos de detecção de patógenos, em geral, requerem dias para identificação de micro-organismos patogênicos, havendo interesse em uma detecção rápida e precisa em tempo real, os biossensores magnetoelásticos são uma alternativa promissora. Os sensores magnetoelásticos são dispositivos de detecção que podem ser acessados remotamente e sua aplicação no método de biossensoriamento possui sensibilidade mássica para espécies biológicas, oferecendo confiabilidade na detecção de patógenos como Escherichia coli. Neste trabalho, tiras amorfas Metglas 2826MB3 foram revestidas com Au pelos processos de deposição de sputtering e eletrodeposição e segmentadas em lâminas de 5 x 1 mm. Foram avaliados os parâmetros de rugosidade média absoluta (Ra), desvio padrão das alturas da superfície (Rq) e simetria do perfil de distribuição (Rsk) com a técnica de microscopia de força atômica aplicada em três superfícies distintas (lisa, rugosa e polida). Buscando melhorar a sensibilidade de detecção do dispositivo, avaliou-se a influência de diferentes tióis no desempenho de biossensores magnetoelásticos. Os compostos utilizados diferem no tamanho da cadeia carbônica e no grupamento terminal que liga-se ao anticorpo. Sobre a superfície polida revestida com Cr/Au pelo processo de sputtering depositou-se os compostos cistamina (CYS), cisteamina (CYSTE) e ácido mercaptopropiônico (MPA), seguido por anticorpos. Os biossensores foram expostos a solução de bactéria E. coli e a variação da frequência de ressonância foi medida com um analisador de rede. Foi possível constatar que a superfície polida revestida com Cr/Au pelo processo de sputtering apresentou menores valores de Ra e Rq e melhor perfil de distribuição (Rsk) em relação às demais superfícies estudadas. Os biossensores com o composto MPA mostraram um aumento na captação de bactérias em relação aos biossensores com os compostos CYS e CYSTE, porém altos valores de desvio padrão foram observados, dificultando a reprodutibilidade e confiabilidade do biossensor. Os biossensores testados com CYSTE apresentaram maior eficiência e menor limite de detecção em relação aos biossensores testados com CYS, apontando um melhoramento na utilização deste composto. Os resultados foram favoráveis para a detecção da bactéria E. coli, evidenciando que o tamanho da cadeia carbônica e o grupamento terminal influenciam na eficácia da imobilização deste patógeno em biossensores magnetoelásticos. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2016-12-23T12:07:42Z No. of bitstreams: 1 Dissertacao Marcia Dalla Pozza.pdf: 1557950 bytes, checksum: dc75080707940367f6a35094de4afcef (MD5) / Made available in DSpace on 2016-12-23T12:07:42Z (GMT). No. of bitstreams: 1 Dissertacao Marcia Dalla Pozza.pdf: 1557950 bytes, checksum: dc75080707940367f6a35094de4afcef (MD5) Previous issue date: 2016-12-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq. / The magneto-elastic sensors are detection devices that can be remotely accessed and applied as biosensors having a mass sensitivity for detection of biological specimens, offering reliability in the detection of pathogens such as Escherichia coli. The pathogen detection methods generally require days to identify the pathogenic micro-organism, so there is interest in a rapid and accurate detection in real time. The magneto elastic biosensors are a promising alternative for this task. In this work, amorphous ribbons of Metglas 2826MB3 were coated with Au by the processes of sputtering and electrodeposition and segmented into 5 x 1 mm strips. We evaluated the roughness parameters arithmetic average height (Ra), root mean square roughness (Rq) and skewness (Rsk) using atomic force microscopy applied on three different surfaces (smooth, rough and polished). Seeking to improve the detection sensitivity of the device, the performance of the biosensors was evaluated in terms of the effects of different thiols on their performance. The compounds used differ in the size of the carbon chain and the terminal grouping which binds to the antibody. On the polished surface coated with Cr/Au by sputtering, we deposited the compounds cystamine (CYS), mercaptopropionic acid (MPA) and cysteamine (CYSTE), followed by antibodies. The biosensors were exposed to the bacteria E. coli in solution and the variation of the resonance frequency was measured with a network analyzer. It was found that the polished surface coated with Cr/Au by sputtering process showed lower values of Ra and Rq and a better distribution profile (Rsk) in relation to other surface studied. Biosensors employing the compound MPA showed an increase in attracting bacteria in relation to biosensors with CYS and CYSTE, but high standard deviations were observed, thus hampering the reproducibility and reliability of the biosensor. Biosensors tested with CYSTE showed higher efficiency and lower detection limit with respect to biosensors tested with CYS, indicating an improvement in the use of this compound. The results were favorable for the detection of E. coli, indicating that the size of carbon chain and the terminal grouping influence the effectiveness of immobilization of the magneto elastic biosensors.
553

Avaliação da influência de diferentes tióis no desempenho de biossensores magnetielásticos para detecção de escherichia coli

Pozza, Márcia Dalla 12 December 2016 (has links)
Os métodos de detecção de patógenos, em geral, requerem dias para identificação de micro-organismos patogênicos, havendo interesse em uma detecção rápida e precisa em tempo real, os biossensores magnetoelásticos são uma alternativa promissora. Os sensores magnetoelásticos são dispositivos de detecção que podem ser acessados remotamente e sua aplicação no método de biossensoriamento possui sensibilidade mássica para espécies biológicas, oferecendo confiabilidade na detecção de patógenos como Escherichia coli. Neste trabalho, tiras amorfas Metglas 2826MB3 foram revestidas com Au pelos processos de deposição de sputtering e eletrodeposição e segmentadas em lâminas de 5 x 1 mm. Foram avaliados os parâmetros de rugosidade média absoluta (Ra), desvio padrão das alturas da superfície (Rq) e simetria do perfil de distribuição (Rsk) com a técnica de microscopia de força atômica aplicada em três superfícies distintas (lisa, rugosa e polida). Buscando melhorar a sensibilidade de detecção do dispositivo, avaliou-se a influência de diferentes tióis no desempenho de biossensores magnetoelásticos. Os compostos utilizados diferem no tamanho da cadeia carbônica e no grupamento terminal que liga-se ao anticorpo. Sobre a superfície polida revestida com Cr/Au pelo processo de sputtering depositou-se os compostos cistamina (CYS), cisteamina (CYSTE) e ácido mercaptopropiônico (MPA), seguido por anticorpos. Os biossensores foram expostos a solução de bactéria E. coli e a variação da frequência de ressonância foi medida com um analisador de rede. Foi possível constatar que a superfície polida revestida com Cr/Au pelo processo de sputtering apresentou menores valores de Ra e Rq e melhor perfil de distribuição (Rsk) em relação às demais superfícies estudadas. Os biossensores com o composto MPA mostraram um aumento na captação de bactérias em relação aos biossensores com os compostos CYS e CYSTE, porém altos valores de desvio padrão foram observados, dificultando a reprodutibilidade e confiabilidade do biossensor. Os biossensores testados com CYSTE apresentaram maior eficiência e menor limite de detecção em relação aos biossensores testados com CYS, apontando um melhoramento na utilização deste composto. Os resultados foram favoráveis para a detecção da bactéria E. coli, evidenciando que o tamanho da cadeia carbônica e o grupamento terminal influenciam na eficácia da imobilização deste patógeno em biossensores magnetoelásticos. / Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq. / The magneto-elastic sensors are detection devices that can be remotely accessed and applied as biosensors having a mass sensitivity for detection of biological specimens, offering reliability in the detection of pathogens such as Escherichia coli. The pathogen detection methods generally require days to identify the pathogenic micro-organism, so there is interest in a rapid and accurate detection in real time. The magneto elastic biosensors are a promising alternative for this task. In this work, amorphous ribbons of Metglas 2826MB3 were coated with Au by the processes of sputtering and electrodeposition and segmented into 5 x 1 mm strips. We evaluated the roughness parameters arithmetic average height (Ra), root mean square roughness (Rq) and skewness (Rsk) using atomic force microscopy applied on three different surfaces (smooth, rough and polished). Seeking to improve the detection sensitivity of the device, the performance of the biosensors was evaluated in terms of the effects of different thiols on their performance. The compounds used differ in the size of the carbon chain and the terminal grouping which binds to the antibody. On the polished surface coated with Cr/Au by sputtering, we deposited the compounds cystamine (CYS), mercaptopropionic acid (MPA) and cysteamine (CYSTE), followed by antibodies. The biosensors were exposed to the bacteria E. coli in solution and the variation of the resonance frequency was measured with a network analyzer. It was found that the polished surface coated with Cr/Au by sputtering process showed lower values of Ra and Rq and a better distribution profile (Rsk) in relation to other surface studied. Biosensors employing the compound MPA showed an increase in attracting bacteria in relation to biosensors with CYS and CYSTE, but high standard deviations were observed, thus hampering the reproducibility and reliability of the biosensor. Biosensors tested with CYSTE showed higher efficiency and lower detection limit with respect to biosensors tested with CYS, indicating an improvement in the use of this compound. The results were favorable for the detection of E. coli, indicating that the size of carbon chain and the terminal grouping influence the effectiveness of immobilization of the magneto elastic biosensors.
554

Avaliação metrológica da incerteza na medição de vazão mássica de gases com tecnologias volumétrica e pressão diferencial

MELO, FLAVIO B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:11Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:02Z (GMT). No. of bitstreams: 0 / A avaliação metrológica da incerteza da medição, apesar de estar normalizada internacionalmente (ISO-GUM, 1995) desde a metade dos anos 90, só agora está se popularizando nas indústrias, nas escolas técnicas e de engenharia. Em algumas áreas, como na metrologia dimensional, está avançada e em outras, como na medição de variáveis de processos industriais tais como vazão, pressão e temperatura, ainda está numa fase intermediara. Um dos principais entraves para essa popularização é a falta de padronização da nomenclatura nas especificações técnicas dos instrumentos de medição, onde se declara a incerteza, por exemplo, de 1% de ?acurácia? sem definir se é percentual da leitura, da faixa calibrada ou da faixa máxima. Ou ainda, sem definir se a probabilidade de abrangência é 68, 95 ou 99,7%. Esse trabalho entra nesse cenário com a pretensão de clarificar e simplificar esses conceitos, começando pelo histórico da evolução do pensamento que transformou a incerteza numa variável quantitativa com sua avaliação efetuada de uma maneira padronizada e internacionalmente aceita. Em seguida é feita uma descrição conceitual sucinta do método ISO-GUM e também é desvendado o intrincado jogo de palavras e fórmulas das declarações de incertezas dos fabricantes de instrumentos de medição. Com o domínio desses conceitos, partimos para efetuar dois exemplos numéricos de avaliação metrológica de incertezas na medição de vazão, usando um conjuntos de fórmulas semelhantes Ás publicadas por renomados fabricantes de instrumentos de medição. No primeiro exemplo usando a medição de vazão por pressão diferencial com placa de orifício e no segundo usando um medidor volumétrico, nos quais são identificadas e quantificadas todas as potenciais fontes de incerteza. A visualização e a analise é feita através de gráficos e planilhas em Excel. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
555

Computer control of an HF chirp radar

Griggs, Desmond Bryan January 1991 (has links)
This thesis describes the interfacing of an IBM compatible microcomputer to a BR Communications chirp sounder. The need for this is twofold: Firstly for control of the sounder including automatic scheduling of operations, and secondly for data capture. A signal processing card inside the computer performs a Fast Fourier Transform on the sampled data from two phase matched receivers. The transformed data is then transferred to the host computer for further processing, display and storage on hard disk or magnetic tape, all in real time. Critical timing functions are provided by another card in the microcomputer, the timing controller. Built by the author, the design and operation of this sub-system is discussed in detail. Additional circuitry is required to perform antenna and filter switching, and a possible design thereof is also presented by the author. The completed system, comprising the chirp sounder, the PC environment, and the signal switching circuitry, has a dual purpose. It can operate as either a meteor radar, using a fixed frequency (currently 27,99 MHz), or as an advanced chirp ionosonde allowing frequency sweeps from 1,6 to 30 MHz. In the latter case fixed frequency doppler soundings are also possible. Examples of data recorded in the various modes are given.
556

Design and control of a teleoperated palpation device for minimally invasive thoracic surgery

Buttafuoco, Angelo 25 February 2013 (has links)
Minimally invasive surgery (MIS) consists in operating through small incisions in which a camera and adapted instruments are inserted. It allows to perform many interventions with reduced trauma for the patient. One of these is the ablation of peripheral pulmonary nodules.<p><p>Nevertheless, the means for detecting nodules during MIS are limited. In fact, because of the lack of direct contact, the surgeon cannot palpate the lung to find invisible lesions, as he would do in classical open surgery. As a result, only clearly visible nodules can be treated by MIS presently.<p><p>This work aims at designing, building and controlling a teleoperated palpation instrument, in order to extend the possibilities of MIS in the thoracic field. Such an instrument is made of a master device, manipulated by an operator, and a slave device which is in contact with the patient and reproduces the task imposed by the master. Adequate control laws between these two parts allow to restore the operator's haptic sensation. The goal is not to build a marketable prototype, but to establish a proof of concept.<p><p>The palpation device has been designed in collaboration with thoracic surgeons on the basis of the study of the medical gesture. The specifications have been deduced through experiments with experiencied surgeons from the Erasmus Hospital and the Charleroi Civil Hospital.<p><p>A pantograph has been built to be used as the master of the palpation tool. The slave is made of a 2 degrees of freedom (dof) clamp, which can be actuated in compression and shear. The compression corresponds to vertical moves of the pantograph, and the shear to horizontal ones. Force sensors have been designed within this project to measure the efforts along these directions, both at the master and the slave side, in order to implement advanced force-feedback control laws and for validation purposes.<p><p>Teleoperation control laws providing a suitable kinesthetic force feedback for lung palpation have been designed and validated through simulations. These simulations have been realized using a realistic model of lung, validated by experienced surgeons. Among the implemented control schemes, the 3-Channel scheme, including a local force control loop at the master side, is the most efficient for lung palpation. Moreover, the increased efficiency of a 2 dof device with respect to a 1 dof tool has been confirmed. Indeed, a characteristic force profile due to the motion in 2 directions appeared in the compression force tracking, making the lesion easier to locate. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
557

The serpent: its characteristics, performance problems, and literature : a lecture recital, together with three recitals of selected works of Stevens, Frescobaldi, Spillman, Wilder, Ritter-George, Russell, and others

Schultz, Russ A. 12 1900 (has links)
The serpent, an extinct musical instrument, was important to the development of contemporary low brass. Its characteristics, performance problems, and literature give insight into its development as well as reasons for its ultimate demise and replacement with technically more advanced instruments.
558

Karakterisering van makroskopiese oppervlakgrofheid met behulp van akoestiese golwe

Blom, C. 29 September 2014 (has links)
M.Ing. (Electrical & Electronic Engineering) / Please refer to full text to view abstract
559

Music for Trombone and Percussion: A Survey and Analysis of Performance Problems of Selected Representative Compositions

Adams, Stan, Adams, Stan January 1981 (has links)
The twentieth century has seen a tremendous growth in the use of the trombone and percussion instruments in chamber music. Stravinsky, in his L'Histoire du Soldat (1917) and Milhaud, in his La Creation du Monde (1927), helped lay the foundation. Two other works, Ionization (1931) by Edgar Varèse and Toccata (1942) by Carlos Chávez are the first of numerous works for percussion ensemble which have since been composed. So many developments of percussion instruments and their music are being made that many consider the twentieth century to be the "Age of Percussion". The trombone family (alto, tenor and bass) has experienced growth in literature and technical advancements but not quite to the degree of the percussion instruments. The development of the trombone choir by Emory Remington at the Eastman School of Music has led to its increased popularity in recent decades. The multiple trombone jazz groups of J. J. Johnson and Kai Winding in the 1950's and Urbie Green in the early 1960's have aided in the development of music written for the trombone. It has only been in the last two decades that music of the genre to be discussed here has been explored. Some of the earliest works that fit this category are Porter D. Henry's Suite for Trombone and Percussion and Vinko Globokar's Vibone for trombone and vibraphone, both of which date from 1963. Since that time, more than 90 works have been composed for one or more trombones and percussion instruments or for small mixed ensembles in which these instruments play a major role. The International Trombone Association and the Percussive Arts Society have done a great deal to advance both the literature and development for the trombone and for percussion. The following document will analyze performance problems involved in a number of representative works from the literature. It will also provide a listing of compositions for trombone and percussion alone or in a chamber music setting of up to five performers.
560

An investigation of solar radio noise in relation to visible phenomena

Poole, Lex Martin Graham January 1961 (has links)
The work of previous writers on the origin and propagation of solar radio noise, and particularly the correlation with visual events is reviewed, and then the construction of the author's 300 Mc/s receiver described. With a view to the author's project, absorption of electromagnetic radiation in the solar corona is quantitatively discussed, and a method for determining the intensity without absorption of a radio burst is evolved. The main project involves briefly the discovery of any possible relationship between the magnitude of a visual flare and the corrected intensity of an associated radio burst as measured at 125 Mc/s. It is concluded that no definite relation exists, but from this consideration an approximate shape of the instantaneous frequency profile of outburst elements is obtained. An extension of the theory to isolated bursts enables us to predict both this bandshape, and the velocity of an exciting agency moving radially through the corona.

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