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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

Měřič krevního tlaku / Blood pressure monitor

Kučera, Michal January 2020 (has links)
This thesis deals with the design and realization of a prototype of non-invasive blood pressure monitor based on the principle of Korotkoff sound detection. The design compares this method of measuring blood pressure with other methods. This design of an automated measuring system, which is controlled by a microprocessor, utilizes the scanning of Korotkoff sounds with an electret microphone placed in the cuff. The microphone signal is then amplified, filtered and adjusted for evaluation. The prototype uses processor-controlled inflation by the compressor and deflation of the cuff by a valve that is open without applied voltage.
32

VYUŽITÍ ELEKTRONICKÝCH MEŘÍCÍCH SYSTÉMŮ PŘI SLEDOVÁNÍ STAVEBNÍCH KONSRUKCÍ / THE USE OF ELETRONIC MEASURING SYSTEMS FOR MONITORING STRUCTURES

Kovács, Pavel Unknown Date (has links)
This thesis deals with the use of the electronic measuring systems for monitoring structures. The first part of this work is focused on mapping the available measuring systems for monitoring deformations and strains, from the point of their measurement accuracy, the real advantages and disadvantages, including examples of monitoring of constructions. In the second part were selected measuring systems for monitoring strains and deflection interest structure. Subsequently, the measuring system with online recording into the tested roof structure was installed and the loading test was performed. Obtained data were compared with other two independent measurements. In the last part of the thesis, the measured values of each independent measurements were compared together, and with the values calculated from the mathematical model. The achieved results show that the installed monitoring system is capable to reliably measure deformation of the structure in real time and thus to warn the building administrator against the potential danger in advance.
33

[en] AUTOMATED SYSTEM FOR MAPPING FERROMAGNETIC FOREIGN BODIES USING GMI MAGNETOMETER / [pt] SISTEMA AUTOMATIZADO PARA MAPEAMENTO DE CORPOS ESTRANHOS FERROMAGNÉTICOS UTILIZANDO MAGNETÔMETRO GMI

BRYAN RODRIGUES CUPELLO DE OLIVEIRA 01 February 2021 (has links)
[pt] A informação sobre o posicionamento de objetos estranhos no interior do corpo humano é essencial para a sua eficiente remoção cirúrgica. Entretanto, os métodos convencionalmente utilizados não fornecem informação suficiente sobre a localização do objeto metálico para garantia de sucesso cirúrgico. No presente trabalho foi desenvolvido um sistema automatizado para mapear a densidade de fluxo magnético estático produzido por corpos ferromagnéticos posicionados em variados graus de liberdade 3D, utilizando um sensor de baixo custo, baseado no fenômeno da magnetoimpedância gigante (GMI - Giant Magnetoimpedance), que detecta somente campos magnéticos variantes no tempo. Assim, as medições automatizadas foram realizadas com a amostra em movimento a uma velocidade constante. Por meio de modelagens computacionais do campo magnético gerado foi possível reproduzir o comportamento da densidade de fluxo magnético gerado por uma fonte de campo magnético como a agulha retilínea utilizada nas medições in vitro. O software considerou as características do sensor GMI utilizado e a condição de medição com a fonte magnética em movimento. Os resultados da simulação foram validados por meio de comparações com os resultados experimentais, possibilitando a solução do problema direto com a caracterização da configuração espacial da densidade de fluxo magnético para variados posicionamentos da fonte magnética em relação ao sensor magnético GMI. Com a validação dos resultados simulados, os mesmos podem ser empregados no desenvolvimento de procedimento para solução do problema inverso de imageamentos clínicos utilizando o sensor GMI de baixo custo, limitado a medições magnéticas variantes no tempo, realizados para detecção e posicionamento de corpos estranhos que geram campos magnéticos estáticos. / [en] Information about the positioning of foreign objects inside the human body is essential for its efficient surgical removal. However, the methods conventionally used do not provide sufficient information on the location of the metallic object to guarantee surgical success. In the present work, an automated system was developed to map the static magnetic flux density produced by ferromagnetic bodies positioned in varying degrees of 3D freedom, using a low-cost sensor based on the giant magnetoimpedance phenomenon (GMI - Giant Magnetoimpedance), which detects only time-varying magnetic fields. Thus, automated measurements were performed with the sample moving at a constant speed. Through computational modeling of the generated magnetic field, it was possible to reproduce the behavior of the magnetic flux density generated by a magnetic field source, such as the straight needle used in in vitro measurements. The software considered the GMI sensor s characteristics and the measurement condition with the magnetic source in motion. The simulation results were validated through comparisons with the experimental results, enabling the solution of the direct problem with the characterization of the spatial configuration of the magnetic flux density for various magnetic source positions in relation to the GMI magnetic sensor. With the validation of the simulated results, they can be used in the development of a procedure to solve the inverse problem of clinical imaging using the low-cost GMI sensor, limited to time-varying magnetic measurements, performed for the detection and positioning of foreign bodies that generate static magnetic fields.
34

On the Impact of Bariatric Surgery on Glucose Homeostasis

Abrahamsson, Niclas January 2016 (has links)
Obesity has grown to epidemic proportions, and in lack of efficient life-style and medical treatments, the bariatric surgeries are performed in rising numbers. The most common surgery is the Gastric Bypass (GBP) surgery, with the Biliopancreatic diversion with duodenal switch (DS) as an option for the most extreme cases with a BMI>50 kg/m2. In paper I 20 GBP-patients were examined during the first post-operative year regarding the natriuretic peptide, NT-ProBNP, which is secreted from the cardiac ventricles. Levels of NT-ProBNP quickly increased during the first post-surgery week, and later established itself on a higher level than pre-surgery. In paper II we report of 5 patient-cases after GBP-surgery with severe problems with postprandial hypoglycaemia that were successfully treated with GLP-1-analogs. The effect of treatment could be observed both symptomatically and in some cases using continuous glucose measuring systems (CGMS). In paper III three groups of subjects; 15 post-GBP patients, 15 post-DS, and 15 obese controls were examined for three days using CGMS during everyday life. The post-GBP group had high glucose variability as measured by MAGE and CONGA, whereas the post-DS group had low variability. Both post-operative groups exhibited significant time in hypoglycaemia, about 40 and 80 minutes per day <3.3mmol/l and 20 and 40 minutes < 2.8mmol/l, respectively, longer time for DS-group. Remarkably, only about 20% of these hypoglycaemic episodes were accompanied with symptoms. In Paper IV the hypoglycaemia counter regulatory system was investigated; 12 patients were examined before and after GBP-surgery with a stepped hypoglycaemic hyperinsulinemic clamp. The results show a downregulation of symptoms, counter regulatory hormones (glucagon, cortisol, epinephrine, norepinephrine, growth hormone), incretin hormones (GLP-1 and GIP), and sympathetic nervous response. In conclusion patients post bariatric surgery exhibit a downregulated counter regulatory response to hypoglycaemia, accompanied by frequent asymptomatic hypoglycaemic episodes in everyday life. Patients suffering from severe hypoglycaemic episodes can often be treated successfully with GLP-1-analogues.
35

Konstrukční návrh lineární osy pro těžký obráběcí stroj / Design of linear axis for heavy machine tool

Kubálek, Petr January 2020 (has links)
This diploma thesis deals with the design of the linear axis of a heavy machine tool. It describes the basic specifications of these machines, their manufacturers, the parts of which the axis consists and the design itself. The design includes several design variants, calculation of the movement mechanism, drive and linear guide. Follows the selection of the most suitable variant and the drawing documentation of the resulting linear axis.
36

[pt] IMPACTOS E BENEFÍCIOS DO SISTEMA DE MEDIÇÃO CENTRALIZADA: ESTUDO DE CASO NUMA CONCESSIONÁRIA BRASILEIRA DE ELETRICIDADE / [en] IMPACTS AND BENEFITS OF THE CENTRALIZED MEASUREMENT SYSTEM: CASE STUDY OF A BRAZILIAN ELECTRICITY UTILITY

08 November 2021 (has links)
[pt] A presente dissertação de mestrado tem por objetivo discutir as bases conceituais e definir os critérios para instalação de um sistema de medição centralizada de energia elétrica na Baixada Fluminense, área de concessão da concessionária de energia do Rio de Janeiro (Light). O estudo estima o consumo de energia e o faturamento médio que resulta da instalação proposta em substituição ao sistema de medição tradicionalmente instalado. A localidade do estudo foi definida tendo em vista o elevado índice de perdas e a vulnerabilidade da rede elétrica exposta à comunidade. Dentre os preceitos metodológicos o trabalho inclui uma revisão bibliográfica da literatura sobre sistemas de medição de energia elétrica e estudo do perfil socioeconômico da região selecionada. O impacto da mudança tecnológica proposta no consumo foi avaliado estatisticamente com base no teste não paramétrico de Wilcoxon. Com base em dados reais de alguns municípios da região, o trabalho inclui também uma análise do comportamento do consumo antes e depois de a alternativa tecnológica ser implementada. / [en] The objective of this research is to discuss the conceptual basis and define the criteria for the installation of a Centralized measurement system in the Baixada Fluminense, concession area of the electricity utility of Rio de Janeiro (Light). The study estimates the energy consumption and the average revenue that results from the implementation of the proposed facility to replace the traditional measurement system in place. The sub area of concession selected was defined based on the following two characteristics: area associated with high rate of electricity losses and vulnerability of the power grid exposed to the community. The methodology used to develop the work included a literature review on systems of electricity metering and a study of the socioeconomic profile of the selected region. The impact of the proposed technological change on the energy consumption was statistically evaluated based on the nonparametric Wilcoxon test. Based on real data from municipalities located in the region, an analysis of energy consumption behavior was carried out before and after the technology alternative was implemented.
37

Systém pro optické měření / Optical measurement system

Opravil, Jan January 2012 (has links)
This diploma thesis deals with the creation and testing of optical measurement system. There are basic parts of computer vision. Some ways of image preprocessing and templates matching are discussed. Everything is directed to a particular practical task. Selected methods for templates matching are the Correlation Method, the Classical and Hybrid Hausdorff Distance, Radial and Circular Sampling Space. These methods are programmed in C++ and they are compared with function for searching templates from specific library.
38

Provozní parametry FV panelů pracujících v hybridních energetických systémech – porovnání / Operating parameters of the PV modules operating in hybrid energy systems - comparison

Jílek, Milan January 2015 (has links)
The master’s thesis deals with the principle of the photoelectric effect, the composition of the photovoltaic cell and different types of solar panels. Here is described the principle of converting wind energy into electricity. This master’s thesis describes reasons for using of the hybrid system. The next section describes the measurement system which is used to measure real operating statuses. The last section is an analysis of measured values and there are listed factors influencing the design of hybrid power system.
39

Návrh metodiky pro volbu základních komponent lineárních os obráběcího stroje / Design methodology for the selection of basic components of linear machine tool axes

Král, Stanislav January 2012 (has links)
The aim of the thesis is based on specified parameters positioning units, which include stroke (1m, 2m, 4m), load (5kg, 50kg, 500kg), you place the position accuracy (0.04 mm) and dynamic (maximum attainable speed 1.5 m / s), proposals to build a ball screw, linear motor, a toothed belt and toothed comb. For selected variants of positioning units to design a 3D model of positioning units. The proposed variations to compare and define their advantages / disadvantages, techno-economic comparison, the limit values of individual designs, etc. The work includes a search drive in positioning units, design units with toothed belt, a toothed comb, ball screw linear actuator, a calculated message of individual proposals then 3D design options for the ball screw and linear motor including drawings and assembly drawings.
40

Modelová studie účinků ultrazvuku na vývoj plodu / Model Study of Ultrasound Effects on Fetal Development

Jaroš, Josef January 2009 (has links)
The progress in ultrasound techniques goes hand in hand with increasing of diagnostic machine acoustic outputs. Ultrasound biological effects can adversely influence the development of human fetus. Recent studies of thermal effect on biological tissues are usually based on simulation of simple ultrasound transducers. The aim of this work is to build a flexible model of diagnostic system to simulate temperature increase during fetal development. Different types of ultrasound probes were used for generation of acoustic field with simulated piezoelectric element properties. Optimized linear and phased arrays were modeled with dynamic beam steering and focus. Computer simulations were concentrated on extreme conditions in obstetric ultrasonography and 3D tissue model was compared with real ultrasound probes measurements. To detect temperature increase, the bone tissue phantom was used. Results point out potential risks for fetus with diagnostic ultrasound probes. Based on the results of this work, practical recommendations increasing safety of obstetric examinations were drawn.

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