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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.
31

Eficácia dos integradores químicos x indicadores biológicos no monitoramento dos ciclos de esterilização a vapor: revisão sistemática da literatura / Efficacy of chemical integrators x biological indicators in the monitoring of steam sterilization cycles: systematic review of literature

Maria Antonieta Velosco Martinho 24 April 2007 (has links)
Este estudo trata-se de uma revisão sistemática cujo objetivo foi levantar as evidências na literatura científica da eficácia dos integradores químicos no monitoramento dos ciclos de esterilização a vapor. As estratégias de busca foram realizadas nas bases de dados MEDLINE, LILACS, CINAHL, DEDALUS, OVID, Cochrane e Google Acadêmico, através de combinações dos termos esterilização (sterilization), integrador químico (chemical integrator), indicador químico (chemical indicator), indicador biológico (biological indicator), monitoramento (monitoring) e reagente (reagent). Foi realizado ainda busca em árvore das referências dos artigos selecionados. Os estudos foram selecionados sem restrições quanta a data de publicação e a língua, com critérios de inclusão de estudos básicos experimentais comparativos quanto ao desempenho dos indicadores químicos frente a cinética de morte microbiana ou resultados obtidos por meio de indicadores biológicos em ciclos de esterilização a vapor e exclusão de estudos realizados com métodos de esterilização que não a vapor e estudos que evidenciam utilização de indicadores químicos classes 1, 2, 3 e 4. No total foram selecionados 7 estudos, sendo que o mais antigo data 1975 e o mais recente 2006, 6 destes estudos compararam indicadores químicos à indicadores biológicos e 1 estudo comparou indicadores químicos frente a curva da cinética de morte microbiana dos Bacillus stearothermophilus. Em relação à origem dos estudos 1 é europeu e 6 americanos, sendo 1 destes brasileiro. Para análise e avaliação dos estudos utilizou-se a seguinte categorização: escopo, tipo de estudo, unidades amostrais, amostra, esterilizador utilizado, procedimentos, análise dos dados, limitações, resultados, conclusões e comentários. Observou-se uma tendência de utilização de temperaturas de 132º e 121ºC para a realização dos experimentos. O tamanho amostral variou de 1 a 47 indicadores por ciclo e o número de ciclos reproduzidos de 1 a 12. Não houve uma tendência em relação aos esterilizadores utilizados e tempos de exposição adotados. 4 estudos utilizaram integradores químicos nos experimentos, sendo que 2 destes utilizaram indicadores não classificados, concomitantemente. Analisando os resultados dos estudos conclui-se que nenhum integradores classe 5 nem indicadores biológicos apresenta respostas 100% sensíveis ou 100% específicas quanto ao desempenho esperado e que Integradores químicos classe 5 e indicadores biológicos apresentam variações de sensibilidade e resistência muito próximos uns dos outros, não cabendo neste momento classificá-los numa escala de efetivos a não efetivos. Os resultados obtidos dos integradores classe 6 mostram 100% de viragem dentro do tempo estimado, sugerindo que estes integradores são efetivos para o monitoramento dos ciclos a vapor / This study is a systematic review, with the objective of collecting evidences in the scientific literature, on the efficacy of the chemical integrators in the monitoring of the steam sterilization cycles. The search strategies were carried out in the MEDLINE, LILACS, CINAHL, DEDALUS, OVID, Cochrane and Academic Google data bases, through the combination of the terms sterilization (esterilização), chemical integrator (integrador químico), chemical indicator (indicador químico), biological indicator (indicador biológico), monitoring (monitoramento), and reagent (reagente). A search in the references tree of the selected articles was also carried out. The studies were selected without restrictions concerning publication date and language, with inclusion criteria of basic experimental comparative studies as for the performance of chemical indicators concerning the kinetics of the microbial death or the results obtained by means of biological indicators in steam sterilization cycles and, the exclusion of studies carried out with non–steam sterilization methods and studies that show the use of chemical indicators classes 1, 2, 3 and 4. A total of 7 studies were selected, the oldest from 1975 and the most recent from 2006; 6 of these studies compared chemical indicators to biological indicators and 1 study compared chemical indicators facing the microbial death kinetics curve of the stearothermophilus Bacillus. In relation to the origin of the studies, 1 is European and 6 are American, 1 of them being Brazilian. For the analyses and assessment of the studies, the following categorization was used: purpose, kind of study, sample units, sample, sterilizer used, procedures, data analyses, limitations, results, conclusions and comments. It was observed a trend of utilization of temperatures between 132º and 121º Celsius for the carrying out of the experiments was observed. The sample size varied from 1 to 47 indicators per cycle and the number of cycles reproduced from 1 to 12. There was no trend concerning the sterilizers used and the exposure time periods adopted. Four studies used chemical integrators in the experiments, and 2 of them used non-classified indicators, concurrently. By analyzing the results of the studies, we came to the conclusion that neither class 5 integrators nor biological indicators present 100% sensitive or 100% specific answers, as for the expected performance, and the class 5 chemical integrators and the biological indicators present variations of sensibility and resistance very close to each other, thus, at the moment they should not be classified in a effective to non-effective scale. The results obtained from integrators class 6 show a 100% turning inside the estimated time, suggesting that these integrators are effective for the monitoring of the steam cycles
32

Multi-agent System Distributed Sensor Fusion Algorithms

Bhattacharya, Shaondip January 2017 (has links)
The concept of consensus filters for sensor fusion is not an entirely new proposition but one with an internally implemented Bayesian fusion is. This work documents a novel state update algorithm for sensor fusion which works using the principle of Bayesian fusion of data with variance implemented on a single integrator consensus algorithm. Comparative demonstrations of how consensus over a pinning network is reached are presented along with a weighted Bayesian Luenberger type observer and a ’Consensus on estimates’ algorithm. This type of a filter is something that is novel and has not been encountered in previous literature related to this topic to the best of our knowledge. In this work, we also extend the proof for a distributed Luenberger type observer design to include the case where the network being considered is a strongly connected digraph.
33

ACID: arquitetura de controle para integração de dispositivos / ACID: control architecture for device integration

Dalton Matsuo Tavares 03 December 2010 (has links)
O objetivo desta tese é adaptar um modelo de integração industrial baseado no protocolo de comunicação XML Interface for Robots and Peripherals (XIRP), de modo que este pudesse ser aplicado à realidade de pequenas e médias empresas brasileiras (PMEs). Para que isto fosse possível, é necessário estudar os ambientes industriais existentes e a complexidade envolvida na tarefa de integração de dispositivos para os mesmos. Observa-se que estes ambientes são orientados a fabricante com relação às soluções criadas em termos de equipamentos e softwares. Este é o exemplo de grandes empresas como ABB, KUKA, Reis Robotics etc. O fabricante detém a solução de integração e os dispositivos, e estes só podem ser integrados em plataformas deste fabricante. O protocolo de comunicação industrial, no caso o protocolo XIRP, possibilita a comunicação entre dispositivos e sistemas controladores de maneira padronizada, permitindo que dispositivos de um fabricante se comuniquem com sistemas de outros fabricantes. Este protocolo é baseado na linguagem eXtensible Markup Language (XML) e fornece a especificação dos arquivos de esquema XML (XML schema), os quais permitem a criação de uma descrição de dispositivos e a composição de mensagens a serem trocadas entre eles. Para tanto, foi necessário criar a partir do padrão, toda a infra-estrutura de comunicação e sistema de integração de dispositivos. Vale observar que o padrão XIRP foi criado levando em consideração dispositivos microprocessados. Como este padrão ainda está em desenvolvimento, e em caso de uma eventual adaptação a ele, seria impraticável modificar inteiramente um ambiente de produção por meio de substituição de equipamentos. Desta forma, este projeto de pesquisa apresenta uma infra-estrutura que consista em um sistema integrador para a adaptação gradativa a este protocolo de comunicação. O sistema integrador proposto permite a incorporação de dispositivos XIRP ou não-XIRP. Considerando que um dispositivo já troque mensagens compatíveis com o XIRP, a sua integração e operação em um ambiente de produção seria mais simples. Todavia, mesmo neste caso, o dispositivo ainda precisaria de suporte para trabalhar em uníssono com as demais entidades pertencentes ao ambiente. Esta sinergia é incluída na especificação do ambiente integrador, porém, não faz parte dos resultados pretendidos para a presente pesquisa. Desta forma, a hipótese prevista trata os mecanismos necessários para a incorporação de dispositivos não-XIRP em um ambiente de produção compatível com o padrão XIRP, desde o processo de indexação/identificação do dispositivo à geração automática da aplicação de controle e integração em baixo nível, de modo a permitir a operação do mesmo. / The goal of this research is to adapt an industrial integration model based on the XML Interface for Robots and Peripherals (XIRP) communication protocol, such that it could be applied to the reality of Brazilian small and medium enterprises (SMEs). In order to enable this, it is necessary to study the existing industrial environments and the complexity involved in the device integration task. We observed these environments are manufacture centered considering the solutions created in terms of equipments and softwares. This is the example set by manufacturers like ABB, KUKA, Reis Robotics etc. The manufacturer detains the integration solution and the devices, and these can only be integrated in platforms of the same manufacturer. The industrial communication protocol, in this case XIRP, enables the communication among devices and controller systems in a standardized way, allowing devices from one manufacturer to communicate with systems from another. This protocol is based on the eXtensible Markup Language (XML) and supplies the specification of the XML schema files, which allows the crea- tion of a device description and the composition of messages to be exchanged among devices. Therefore a communication infrastructure and device integra- tion system was built from the standard. Note that the XIRP standard was created considering processor based devices. As this standard is still in development, and in case of an eventual adaptation to it, it would be impracticable to change an entire production environment by means of equipment exchange. Therefore, this research project presents an infrastructure that consists in an integrator system to gradually adapt to this communication protocol. The proposed integrator system allows the incorporation of XIRP or non-XIRP devices. Considering a device already exchanges messages by means of XIRP compliant messages, its integration and operation would be simpler in a production environment. However, even in this case, the device would still need support to operate in unison with other entities pertaining to the environment. This synergy is included in the specification of the integrator environment, although, it is not part of the intended results for this research. Therefore, the foreseen hypothesis deals with the necessary mechanisms to incorporate non-XIRP devices in a production environment compliant with the XIRP standard, from the device indexing/identification to the automatic generation of the control application and its low level integration, in order to allow its operation.
34

Fluxmetr s grafickým zobrazením B-H křivky / Fluxmeter with graphical display of B-H curve

Ježek, Jaroslav January 2010 (has links)
This work deals with simple fluxmeter which is able, together with other device, to show hysteresis loop. Hysteresis loop is a graphic expression of dependence of magnetic induction on intensity of magnetic field. Oscilloscope is used to display the hysteresis loop. This device is fully sufficient for the display. The measured objects are solenoids from various kinds of materials with the same shape. The main aim of this work is the design, realization and description of the fluxmeter. The fluxmeter consists of several partial blocks. The first one, on which this work is focused, is signal generator which is able to generace different kinds of signal. The generated signal comes on primary winding of solenoid where a magnetic field on a given intensity rises. An amplifier is used to obtain the sufficient intensity. Next thing this work is focused on is the design of the integrator which is necessary for the correct function of the fluxmeter. As suggested, there is shown the block diagram of linking of individual parts. There are described the measured results at the end of this work.
35

Impact of non-idealities and integrator leakage on the performance of IR-UWB receiver front end

Navineni, Tharakaramu January 2012 (has links)
UWB has the huge potential to impact the present communication systems due to its enormous available bandwidth, range/data rate trade-off, and potential for very low cost operation. According to FCC, Ultra Wideband (UWB) radio signal defined as a signal that occupies a bandwidth of 500 MHz or fractional bandwidth larger than 20% with strict limits on its power spectral density to -41.3dBm/MHz in the range 3.1GHz to 10.6GHz. Decades of research in the area of wide-band systems have lead us to new possibilities in the design of low power, low complexity radios, comparing with existing narrowband radio systems. In particular, impulse radio based ultra wideband (IR-UWB) is a promising solution for short-range radio communications such as low power radio-frequency identification (RFID), wireless sensor network's and wireless personal area network (WPAN) etc. Since a simple circuit, architecture adopted in the IR-UWB system, the non-idealities of receiver front end may lead to degrade the overall performance. Therefore, it is important to study these effects in order to create robust and efficient UWB system. However, majorities of recent studies are formed on the channel analysis, rather than the receiver system. The main objectives of this thesis work are, (a) System level modeling of non-coherent IR-UWB receiver, (b) Performance analysis of IR-UWB receiver with the help of bit error rate (BER) estimation, (c) A study on the impact of receiver front end non-idealities over BER, (d) Analysis of charge leakage in integrator and its effect on overall performance of UWB receiver. In this work, IR-UWB non-coherent energy detector receiver operating in the frequency band of 3GHz-5GHz based on the on-off keying (OOK) modulation was simulated in Matlab/Simulink. The effect of receiver front end non idealities and integrator charge leakages were discussed in detail with respect to overall performance of the receiver. The results show that non idealities and leakage degrade the performance as expected. In order to achieve a specific BER of 10-2 with the integrator leakage of 25%, the SNR should be increased by 2.1 dB compared to the SNR with no leakage at a data rate of 200Mbps. Finally, integrator design and its specifications were discussed.
36

Leistungsbasierte Steuerung der Dienstleistungsnetzwerke von Service-Integratoren in der Logistik

Klarmann, Axel 10 July 2017 (has links)
Die vorliegende Arbeit setzt sich mit den Steuerungsanforderungen in einem Wertschöpfungsnetzwerk eines Service-Integrators auseinander. Hierzu wird zunächst das Geschäftsmodell des Service-Integrators abgegrenzt und eine Einordnung in eine Typologie von Netzwerkunternehmen vorgenommen. Anschließend erfolgt eine Untersuchung der Steuerungsbedarfe aus organisationstheoretischer Sicht und ein Abgleich mit entsprechenden Instrumenten von bestehenden Arbeiten aus dem Bereich der Steuerung von Unternehmensnetzwerken. Es wird dabei gezeigt, dass die Konzepte Vertrauen und Reputation nicht inkludiert sind, woraufhin ein leistungsbasiertes Verständnis von Reputation, auf Basis von Vertragsverletzungen, aufgebaut wird, nachdem ein entsprechendes Verständnis von Vertrauen und Reputation aus betriebswirtschaftlicher Literatur abgeleitet wurde. Dieses Instrument wird, im Rahmen eines auf Basis von SCOR entwickelten Kennzahlenmodells, als Instrument zur Steuerung von Netzwerken von Service Integratoren aufgebaut. Abschließend erfolgt eine prototypische Umsetzung und damit die Evaluierung der Machbarkeit und Gültigkeit unter den getroffenen Annahmen, dieses Instruments im Rahmen eines Instruments für einen logistischen Service-Integrator. Im Zuge der Arbeit wird gezeigt, dass die Steuerung des Netzwerks eines Service-Integrators besondere Anforderungen an eine Netzwerksteuerung stellt, welche durch ein erweitertes, leistungsbasiertes Instrument, auf Basis der Verhaltenshistorie erfüllt werden können.
37

Comparison and Analysis of Attitude Control Systems of a Satellite Using Reaction Wheel Actuators

Kök, Ibrahim January 2012 (has links)
In this thesis, analysis and comparison of different attitude control systems of a satelliteusing different reaction wheel configurations were investigated. Three different reactionwheel configurations (e.g. tetrahedron configuration, pyramid configuration, standardorthogonal 3-wheel configuration) and three control algorithms (Linear Quadratic Regulator,Sliding Mode, Integrator Backstepping) were analyzed and compared in terms of settlingtimes, power consumptions and actuator failure robustness. / <p>Validerat; 20121205 (global_studentproject_submitter)</p>
38

Control of Quadcopter UAV by Nonlinear Feedback

Ye, Haoquan 04 June 2018 (has links)
No description available.
39

An Audio Processing System as an Example of Modern Circuit Board Design

Asar, Sita Madhu January 2016 (has links)
No description available.
40

Projeto de um manipulador robótico cilíndrico de cinco eixos atuado por motores de passo

Silveira, Iago Camargo January 2018 (has links)
Este trabalho contempla o projeto de um manipulador robótico cilindro atuado por motores de passo com cinco juntas de atuação. As etapas do projeto do robô, que tratam este estudo, foram divididas em: projeto mecânico; modelagem matemática; projeto do controlador; e simulações. O projeto mecânico apresenta uma proposta de configuração e dimensionamento mecânicos que supre a demanda exigida para a operação analisada. O modelo matemático apresenta as características elétricas e mecânicas do atuador e as características mecânicas do robô. O projeto de um controlador linear é realizado por meio da alocação dos polos do sistema em malha fechada através da realimentação dos estados de posição e de velocidade angulares do rotor unidos a um integrador do erro de posição angular. Para o primeiro grau de liberdade, por conta da variação do momento de inércia de massa associado a essa junta, um controlador com ganhos parametrizados foi projetado, no qual os ganhos são calculados baseado no modelo matemático relativo ao momento de inércia de massa associado a essa junta. Por meio de simulações computacionais, avaliou-se o projeto dos controladores no movimento ponto a ponto dos cinco eixos de atuação e a variação do momento de inércia de massa sobre a primeira junta. Os resultados dessas simulações mostraram que os controladores propostos cumprem com a dinâmica desejada nos cinco graus de liberdade do robô. / This work contemplates the design of a robotic manipulator, which is operated by a stepper motor with five actuation joints. The robot design steps were divided into: mechanical design; mathematical modeling; controller design; and simulations. The mechanical design presents a proposal of mechanical configuration and sizing that supplies the required demand for the analyzed operation. The mathematical model presents the electrical and mechanical characteristics of the actuator and the mechanical characteristics of the robot. The design of a linear controller is accomplished by allocating the poles of the closed loop system by states feedback of the position and angular speed of the rotor attached to an angular position error integrator. For the first degree of freedom, due to the variation of mass moment of inertia associated with this joint, a controller with parameterized gains was projected, in which the gains are calculated based on the mathematical model related to the mass moment of inertia associated to this joint. By means of computational simulations, we evaluated the design of the controllers in the point-to-point movement of the five actuation joints and the variation of the mass moment of inertia on the first joint. The results of these simulations showed that the proposed controllers comply with the desired dynamics in the robot’s five degrees of freedom.

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