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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

[pt] AVALIAÇÃO DE ANALISADOR HEMATOLÓGICO BASEADO EM MEDIÇÕES ÓPTICAS DIRETAS USANDO LED AZUL PARA CONTAGEM DIFERENCIAL DE LEUCÓCITOS / [en] EVALUATION OF HEMATOLOGY ANALYZER BASED ON DIRECT OPTICAL MEASUREMENTS USING BLUE LED FOR DIFFERENTIAL LEUKOCYTE COUNTING

VICENTE MONTEIRO LORENZON 14 January 2020 (has links)
[pt] Os analisadores hematológicos são sistemas de medição que permitem identificar elementos sanguíneos, incluindo a contagem diferencial dos cinco tipos de leucócitos encontrados no sangue periférico: neutrófilos, linfócitos, monócitos, eosinófilos e basófilos. Devido à inexistência de materiais de referência certificados ou métodos de referência para a análise diferencial de leucócitos, tem sido habitual avaliar o desempenho de novos analisadores comparando-os com sistemas tradicionalmente disponíveis e bem consolidados. Em 2015, foi lançada uma nova tecnologia portátil e de baixo custo, o modelo DxH500 (Beckman Coulter), baseada na perda axial de luz usando LED azul como emissor, combinada à medição de impedância. O presente trabalho compara o desempenho do DxH500 com um modelo bastante utilizado desde seu lançamento em 2001 para exames laboratoriais em larga escala, o modelo LH750 (Beckman Coulter), baseado na combinação dos princípios de impedância, condutividade e dispersão de luz (VCS). No estudo foram examinadas 310 amostras pareadas. A análise comparativa entre os resultados fornecidos por cada dispositivo indicou uma boa correlação para a caracterização de neutrófilos, linfócitos, monócitos e eosinófilos. Apesar da reduzida correlação observada para a contagem de basófilos, esse resultado não apresenta relevância clínica já que os valores obtidos para as amostras avaliadas foram muito reduzidos, inferiores aos limites de referência. Embora a análise comparativa realizada tenha apontado para um desempenho equivalente utilizando-se tecnologias com princípios diversos, a adequada avaliação dos dispositivos de análise hematológica requer o desenvolvimento de materiais de referência certificados, uma demanda fundamental para a garantia da confiabilidade na quantificação diferencial de leucócitos. / [en] Hematology analyzers are measurement systems that allow the identification of blood elements, including differential counting of the five types of leukocytes found in peripheral blood: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Because of the lack of certified reference materials or reference methods for differential leukocyte analysis, it has been customary to evaluate the performance of new analyzers by comparing them with traditionally available and well-established systems. In 2015, a new low-cost, portable technology was introduced, the Beckman Coulter DxH500 model, based on the axial loss of light using blue LED as a combined transmitter for impedance measurement. The present work compares the performance of the DxH500 with a widely used model since its launch in 2001 for large-scale laboratory tests, the Beckman Coulter model LH750, based on the combination of impedance, conductivity and scatter (VCS). In the study, we examined 310 paired samples. The comparative analysis between differential leukocyte evaluation results provided by each device indicated a good correlation for the characterization of neutrophils, lymphocytes, monocytes, and eosinophils. Despite the low correlation observed for basophil counts, this result is not clinically relevant since the values obtained for the evaluated samples were very low, lower than the reference limits. Although the comparative analysis carried out pointed to an equivalent performance using technologies with different principles, the adequate evaluation of hematological analysis devices requires the development of certified reference materials, fundamental demand for the reliability of the differential quantification of leukocytes.
32

Metodika zabezpečování optimální přesnosti měření v souladu s metrologickou konfirmací / The Optimal Accuracy of Measurement Assurance in Accordance with Metrological Confirmation

Frank, Petr January 2009 (has links)
This thesis deals with the evaluation of accuracy of measurement and achieving the required accuracy level. This includes global analysis of the uncertainty evaluation, the calibration interval design and the creation of confirmation system. Basis of this work is in identification of all possible problems, which may occur during evaluation of accuracy and achieving the required accuracy level. The analysis is followed by suggested solutions for identified problems. It means namely the selection of probability distribution in case of uncertainty type A, evaluation of degrees of freedom in case of uncertainty type B, nonlinear correlation of input values, evaluation of coverage factor, the choice of method for calibration interval design and the procedure for meeting all metrological confirmation requirements. The last part of the thesis is practical measurement and result evaluation in the field of surge protection devices. This chapter demonstrates conclusions from the syntactical part.
33

Návrh vhodného etalonu délky pro nano-CT měřicí přístroj / Design of a suitable length standard for nanp-CT measuring device

Kožiol, Martin January 2020 (has links)
The diploma thesis deals with the design of three length standards, which will serve to ensure metrological traceability between Rigaku nano3DX, SIOS NMM-1, Zeiss UPMC Carat 850 and other devices located at ÚVSSR BUT and CEITEC Brno. The first part of the thesis focuses on the theoretical acquaintance with concepts closely related to the issue of ensuring metrological traceability. In addition, this section deals with computed tomography and the description of individual devices. The second part of the thesis is devoted to design, production process and testing of individual standards. The last part describes the ensuring the calibration of the smallest standard, the so-called Nano standard and the calculation of the uncertainty of measuring its calibrated length. At the end of the thesis, the outputs of these activities are evaluated.
34

Electronics Authenticity Testing Using Comprehensive Two-Dimensional Gas Chromatography

Joseph C Cacciatore (8082794) 05 December 2019
<p>Technology has become increasingly more prevalent in all aspects of society since the age of the computer. The United States Military has successfully integrated the powerful processing capabilities of computers to increase the proficiency and lethality of its Soldiers, Sailors, Marines, and Airmen. However, this increased lethality comes at risk due to the inherent vulnerabilities of computer systems to spyware, malware, and counterfeit components. Inspired by the ability of canines to seek out and find electronic devices, this research sought methods to characterize components by their “scent” using precise analytical tools. Using these tools, this thesis sought to develop and utilize non-invasive methods to show proof-of-concept for electronic device classification by volatile compounds unique to different types of components. The findings of this research proved that electronic components that vary by age, origin, type, or manufacturer emit different volatile compounds available for detection using modern two-dimensional gas chromatography and solid-phase microextraction technologies. If developed further, the methods used in this research have the potential for application in the United States Department of Defense to ensure that all electronic components installed in their systems are authentic, come from a trusted source, and can be relied upon in even the most stressful operating conditions.</p>
35

Автоматизация контроля и сортировки бомбинированных подшипниковых роликов по биению сферического торца : магистерская диссертация / Automation of control and sorting of bombed bearing rollers according to the beating of a spherical end

Чирков, Д. А., Chirkov, D. A. January 2019 (has links)
Цель работы – разработка, исследование точности и конструирование измерительной станции для контроля биения сферического торца ролика радиального двухрядного сферического подшипника качения на базе существующего автомата (А-2292-М) для контроля гранности бочкообразных роликов. В ходе работы была предложена метрологическая схема, необходимая для контроля сферического торца ролика, исследована её точность, разработана конструкция измерительной станции. Показана реализация измерительной системы в конструкции автомата для контроля гранности с двумя вариантами источников вращения ролика в процессе измерения. Проведен расчет экономической эффективности от повышения качества роликов и увеличения межремонтных периодов. В основу измерительного узла положено использование индуктивного (автогенераторного) датчика и элемента посредника совместно с метрологической схемой, представленной в работе. / The aim of the work is to develop, study the accuracy and design of a measuring station for monitoring the runout of a spherical roller end of a radial two-row spherical rolling bearing based on an existing machine (A-2292-M) to control the granularity of barrel rollers. In the course of the work, a metrological scheme was proposed, which was necessary to control the spherical end of the roller, its accuracy was investigated, and the design of the measuring station was developed. The implementation of the measuring system in the design of the automatic machine for control of granularity with two options for sources of rotation of the roller in the measurement process is shown. The calculation of economic efficiency from improving the quality of rollers and increasing the period between repairs is carried out. The basis of the measuring node is the use of an inductive (auto-oscillating) sensor and an intermediary element in conjunction with the metrological scheme presented in the work.

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