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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.
261

Development of an Instrumented Mannequin for Training of Caregivers in Safe Patient Handling and Movement

Westhoff, Oneida Dugarte 16 March 2004 (has links)
A common problem associated with patient handling is the risk of bodily injury due to acute or cumulative trauma. The objective of this research was to develop an integrated solution, using commercially available components, to help health care providers handle patients in a safe manner. The objective was achieved by retrofitting a mannequin with flex sensors, electrogoniometers, pressure sensors, and photocells. The sensors were capable of quantifying angular displacement, skin pressure distribution and undignified exposure. All of these variables were monitored by a computer-based data acquisition system. The design of this integrated system was implemented using National Instruments LabView software, which possessed the capability to provide both spasm simulation process control and a history of the acquired sensor data. A virtual instrument, (VI), was developed using LabView as the interface between the user or instructor and the instrumented mannequin. The VI had the capability of displaying the history of the acquired data. With access to the data's history the trainer is able to analyze the sensor information and verify the procedural accuracy of the actions performed on the simulated patient by the student. The system technologies employed can help the instructor improve the training of health care workers. Additionally, providing the trainer with useful information about the student's skill building during interaction with a patient enhances evaluation of the student's performance. Once the data is collected, the instrumented mannequin is capable of identifying problems such as excessive force or pressure when health care providers are interacting with patients. This provides the healthcare community with useful information to improve and provide a safer and more comfortable environment for the patient. The instrumented mannequin will be a valuable tool in evaluating and assessing the merits of clinical procedures. It may also be used in biomechanical studies involving patient handling by caregivers.
262

Etudes liées à la vitrification sans fracture de solutions cryoprotectrices

Odagescu, Valentina Maria 07 July 2005 (has links) (PDF)
La cryopréservation par vitrification est une technique qui devrait permettre de rallonger considérablement les durées de conservation des greffons en abaissant leur température de stockage jusqu'à – 196°C. Elle nécessite l'utilisation de solutions cryoprotectrices (contenant des antigels biocompatibles) pour empêcher la cristallisation de glace dans les tissus, ainsi que des vitesses de variation de la température relativement rapides. La calorimétrie différentielle à balayage permet de déterminer les vitesses requises pour la vitrification des solutions cryoprotectrices. L'exemple de l'éthylène glycol est présenté, complétant les informations connues sur ce cryoprotecteur dans la plage des concentrations concernant la vitrification. Au niveau de la procédure de vitrification, la méthode du recuit a permis d'éviter l'apparition de fractures dans des volumes importants de solution cryoprotectrice. Le cas particulier de la solution VM3 (21st Century Medicine) est détaillé. Il permet de montrer que la stabilité de l'état amorphe ainsi que la quantité de glace cristallisée au réchauffement sont influencées par la température et la durée du recuit. Une analyse sur l'influence du type et de la forme du container porte-échantillon par rapport à la qualité du verre fabriqué a été commencée en parallèle, mais les limites du dispositif cryogénique utilisé nous ont poussé à développer un nouveau cryostat automatisé, permettant de faire des études systématiques dans des conditions reproductibles. Ce cryostat, entièrement conçu et construit au CRTBT, représente le prototype de ce que nous souhaitons proposer à des médecins pour les aider dans leur étude clinique de la cryopreservation des systèmes biologiques. Sa précision de mesure et sa facilité d'utilisation nous a pour le moment permis de mettre en évidence différents événements ayant lieu pendant la vitrification et le réchauffement de nos échantillons.
263

Integration and data acquisition of an optical spectroscopy and optical transmission properties of bulk GaNP material

Lai, Chun-chen 09 September 2007 (has links)
Our major work is to use LabVIEW as the platform to develop the instrument control programs for measuring the optical and electrical properties of semiconductor materials. To measure the optical properties of semiconductor materials, we developed an optical spectroscopy control program. The program can be modified to make it suitable for many kinds of optical spectroscopy systems. Here we use it to measure the transmission spectrum of GaNP bulk material. To measure the electrical properties of semiconductor materials, we developed a program to record the I-V characteristic curve of the device under test. We can use it to check the ohmic property of contact form between metal electrode and semiconductor material. Finally, we developed a program to record the photoconductivity build-up and decay transient curve.
264

Design And Digital Implementation Of Thyristor Controlled Reactor Control

Genc, Murat 01 December 2007 (has links) (PDF)
In this research work, the control system of 16 MVAr, 13.8 kV TCR will be designed and digitally implemented. A Real-Time Control System (NI CompactRIOTM Reconfigurable I/O) and a Digital Platform (NI LabVIEWTM Gcode) are used in the digital implementation of TCR control system. The digital control system is composed of reactive power calculation, firing angle determination and triggering pulse generation blocks. The performance of control system will be tested in the field. The simulation results will also be compared with test data.
265

Instrumentação virtual aplicada ao ensino experimental de engenharia elétrica. / Virtual instrumentation applied to electrical engineering education.

Vinícius José Santos Lopes 20 September 2007 (has links)
A proposta deste trabalho é apresentar algumas potenciais aplicações do software LabVIEW da National Instruments, associado a um hardware de aquisição de dados, aplicado em experiências ligadas à área de sistemas de energia elétrica como ferramenta de apoio ao ensino presencial. Esta dissertação mostra o desenvolvimento de uma experiência em um laboratório de sistemas de energia elétrica que utilizam sensores Hall de tensão e corrente, uma placa A/ D e o software LabVIEW para monitorar variáveis elétricas, calcular e analisar potência, energia e fator de potência de um minissistema de energia em baixa tensão, que contém geradores síncronos trifásicos de 2kVA-220 V, um modelo de uma linha de transmissão com reatores e capacitores, e uma caixa de resistência para representar uma carga passiva. Uma placa A/ D permite saídas digitais, que por sua vez podem controlar contatores que ligam ou desligam elementos do circuito em análise. Um programa foi desenvolvido para servir como ferramenta de apoio no processo ensino-aprendizagem. Este programa possibilita monitorar e atuar na montagem experimental, disponibilizando três instrumentos virtuais básicos para o desenvolvimento da experiência. Estes três instrumentos são: uma primeira tela que mostra o diagrama dos fasores de todos os sinais de tensão e corrente simultaneamente; uma segunda tela, que mostra a forma de onda dos sinais de tensão e corrente no minissistema com as suas respectivas defasagens; e a terceira e última tela que fornece um sincronoscópio virtual possibilitando analisar os ajustes de tensão e freqüência necessários na operação de paralelismo do minissistema com a concessionária de energia. Este programa possibilita o acesso à montagem experimental do minissistema de energia pelo computador instalado na bancada do laboratório, permitindo também aos alunos, o monitoramento e controle do experimento a partir de seus próprios computadores, visualizando e reforçando no laboratório, os conceitos vistos na teoria. / The proposal of this work is to present some potential applications of the software LabVIEW, from National Instruments, associated with data acquisition hardware, applied to experiments in the Electric Energy Systems area as a tool to support the presential education. This dissertation shows the developing of an experience in a electric energy system laboratory, which use Hall Effect sensors, A/D data acquisition board, connected to a PC, and the software LabVIEW (National Instruments) in order to monitor electrical parameters, calculate and analyze power, energy and power factor in a low-voltage power system, which contains synchronous three-phase generators of 2 kVA-220V, with a transmission line model provided with reactors and capacitors, and a resistance box representing a passive load. The A/D board allows controlling digital outputs that can control counters that switch on or off the circuit elements in the analysis. A program was developed in order to act a tool to support the process teaching-learning. This program allows to monitor and to act in the experimental assembly providing three basic virtual tools for the experiment development. These three tools are: one screen that simultaneously shows the phasor diagram with current and voltage; a second screen that shows voltage and current waveform of the mini-system with its respective imbalances; and the third and last screen, that provides a virtual synchronoscope which makes possible the analysis of the necessary adjustments of voltage and frequency in the operation of parallelism between the mini-system and the energy power supplier. This program allows the access to the experimental assembly of the energy mini-system through a computer installed in a bench of the laboratory. As a result, the students can also monitor and control the experiments through their own computers, allowing them to visualize and to reinforce in the laboratory, the concepts taught in theory.
266

Control of a high temperature DLTS setup

Marklund, Daniel January 2017 (has links)
This thesis deals with a DLTS-setup and how this can be controlled. The controlling program is constructed in LABVIEW, where a previous built program measuring transients at varying pulses been handled and tried to be implemented for this setup. Parts of the program was implemented successfully, other part needs more work. The heater in the setup has further been connected directly to the sample. This one has been tested to see that the setup can handle the heat and that the difference between the temperature at the sample and the setup did not differ too much. The result showed that the difference was not so big. Finally, DLTS tests was performed at samples of silicon carbide as well as on diamond, where transients could be measured up to 723 °C on the silicon carbide sample, while the tests of diamond only gave noise.
267

Design and Validation of an Automated Multiunit Composting System.

Pickens, Mark Everett 12 1900 (has links)
This thesis covers the design of an automated multiunit composting system (AMUCS) that was constructed to meet the experimental apparatus requirements of the ASTM D5338 standard. The design of the AMUCS is discussed in full detail and validated with two experiments. The first experiment was used to validate the operation of the AMUCS with a 15 day experiment. During this experiment visual observations were made to visually observe degradation. Thermal properties and stability tests were performed to quantify the effects of degradation on the polymer samples, and the carbon metabolized from the degradation of samples was measured. The second experiment used the AMUCS to determine the effect of synthetic clay nanofiller on the aerobic biodegradability behavior of poly (3-hydroxybutyrate-co-3-hydroxyvalerate).
268

Automação e controle para fabricação de preformas VAD para fibras opticas de alta uniformidade geometrica / Automation and control for VAD preforms fabrication for optical fibers with high geometrical uniformity

Ono, Eduardo 27 July 2004 (has links)
Orientador : Carlos Kenichi Suzuki / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-04T01:44:29Z (GMT). No. of bitstreams: 1 Ono_Eduardo_M.pdf: 3494337 bytes, checksum: 6a111a737f2e9b27797fca1dc7c3fe90 (MD5) Previous issue date: 2004 / Resumo: Um novo processo VAD ("Vapor-phase Axial Deposition"), em desenvolvimento no Laboratório Ciclo Integrado do Quartzo - LIQC, FEM, UNICAMP, introduz uma série de inovações tecnológicas e maior viabilidade econômica sobre os atuais processos de fabricação de fibra óptica. Para a produção de uma fibra de alta qualidade, a uniformidade geométrica da preforma porosa, gerada na etapa de deposição do processo, possui grande relevância na uniformidade das características da fibra final, tais como a atenuação e a dispersão. Para o controle da geometria da preforma em deposição, desenvolveu-se um sistema em LabVIEW, para a plataforma PC, para atuar continuamente e em tempo real na etapa de deposição de modo a manter o diâmetro da preforma constante. Em sua essência, o sistema de controle realimentado, baseado no controlador PID, atua na velocidade do mecanismo de posicionamento da preforma em função do valor do diâmetro na região inferior da preforma. Esse diâmetro é obtido pelo processamento da imagem adquirida por uma câmera de vídeo CCD da região da preforma em deposição. Embora tenha sido desenvolvido para a escala laboratorial, o sistema mostrou bom desempenho e estabilidade, podendo ser empregado na produção industrial em grande escala de preformas para fibra óptica. Nesse sistema, variações dimensionais no diâmetro da preforma da ordem de 0,3 mm são corrigidos, obtendo-se uma precisão cinco vezes maior quando comparado a sistemas convencionais, favorecendo uma menor incidência de rejeitos de produção de preformas e, conseqüentemente, menor custo de produção / Abstract: An advanced V AD (Vapor-phase Axial Deposition) technique has been developed at Laboratory of Integrated Quartz Cycle - LIQC - FEM - UNICAMP. It introduces a series of technological innovations with a greater economical viability over actual optical fiber manufacturing processes. For a high quality optical fiber production, several steps and process parameters must be carefully set. The geometrical uniformity of the preform during the deposition stage is one of the most important parameter for the final uniformity, which determines the characteristics of the final fiber in terms of attenuation and dispersion. To control the preform geometry during the deposition, a computer system based on Lab VIEW platform was developed, to act continuously and in real time on the deposition stage, in order to maintain constant the preform diameter. In its essence, the feedback system, based on PID controller, acts on the speed of the preform positioning mechanism, according to the value of the diameter detected in. the deposition region. This diameter is obtained through the image processing grabbed from a CCD video camera. Although, it was developed in a laboratorial scale, the system showed a good performance and stability, which can be applied on an industrial mass production scale for fiber optics. In this system, dimensional variations in the order of 0.3 mm on the preform diameter can be corrected, that corresponds to a precision about 5 times better than that achieved by conventional industrial systems, with a benefit of a lower incidence of production rejects and, therefore, a lower production cost / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
269

Návrh uživatelsky přizpůsobitelného automatizovaného systému vizuální kontroly kvality pro montážní linky / Design of customizable automated visual quality control system for assembly lines

Martini, Silvano January 2017 (has links)
The diploma thesis deals with the problematics of machine vision. The research is devoted to description of the machine vision system hardware and software components. In practical part is described design and realization of the software, which allows several tasks of machine vision to be performed at the same time.
270

Systém chránění s využitím výstupu z elektronického senzorického systému měření proudu a napětí / The Protection System Working on Output of Electronic Sensor System Measuring Current and Voltage

Bajánek, Tomáš January 2017 (has links)
At present, there is a widespread use of alternative measurement technologies in electrical networks that include current and voltage sensors. Their use is closely related to the use of IEC 61850-9-2 for data transfer of measured values within the substation for the purpose of protection and measurement. The use of sensors and communication standard IEC 61850 together with high-speed Ethernet will simplify the concept of the arrangement of protection terminals in substations and enable the development of a new protection system based on central protection. The dissertation is focused on protection algorithms, which use the SV according to IEC 61850-9-2, and their implementation into the central protection model. Thesis describes development in the field of protection of substations and the currently available solutions using IEC 61850-9-2 and the principle of central protection. Thesis explains algorithms for selected protection functions - overcurrent protection, negative sequence overcurrent protection, logic busbar protection and differential protection. Further, thesis deals with the programming of protection function algorithms in LabView development environment in the form of a central protection model. The model processes data from a process bus according to IEC 61850-9-2 and sends a GOOSE message over Ethernet in the event of a failure. To verify the correct function of the programmed protection algorithms, a testing procedure was developed using OMICRON 256plus, the current sensor and the merging unit. The results of the testing of the central protection model and the proposed algorithms were compared with the results of testing the currently used protections. At the end, the thesis deals with the assessment of the benefits of central protection for protecting substations and the possibility of further utilization of the central protection model. The thesis highlights a new way of protecting the electrification system using digital data from MU transferred via the process bus described in IEC 61850-9-2.

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