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Measurement uncertainty budget of an interferometric flow velocity sensorBermuske, Mike, Büttner, Lars, Czarske, Jürgen 06 September 2019 (has links)
Flow rate measurements are a common topic for process monitoring in chemical engineering and food industry. To achieve the requested low uncertainties of 0:1% for flow rate measurements, a precise measurement of the shear layers of such flows is necessary. The Laser Doppler Velocimeter (LDV) is an established method for measuring local flow velocities. For exact estimation of the flow rate, the flow profile in the shear layer is of importance. For standard LDV the axial resolution and therefore the number of measurement points in the shear layer is defined by the length of the measurement volume. A decrease of this length is accompanied by a larger fringe distance variation along the measurement axis which results in a rise of the measurement uncertainty for the flow velocity (uncertainty relation between spatial resolution and velocity uncertainty). As a unique advantage, the laser Doppler profile sensor (LDV-PS) overcomes this problem by using two fan-like fringe systems to obtain the position of the measured particles along the measurement axis and therefore achieve a high spatial resolution while it still offers a low velocity uncertainty. With this technique, the flow rate can be estimated with one order of magnitude lower uncertainty, down to 0:05% statistical uncertainty.1 And flow profiles especially in film flows can be measured more accurately. The problem for this technique is, in contrast to laboratory setups where the system is quite stable, that for industrial applications the sensor needs a reliable and robust traceability to the SI units, meter and second. Small deviations in the calibration can, because of the highly position depending calibration function, cause large systematic errors in the measurement result. Therefore, a simple, stable and accurate tool is needed, that can easily be used in industrial surroundings to check or recalibrate the sensor. In this work, different calibration methods are presented and their in uences to the measurement uncertainty budget of the sensor is discussed. Finally, generated measurement results for the film flow of an impinging jet cleaning experiment are presented.
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LDPC DropConnectChen, Xi January 2023 (has links)
Machine learning is a popular topic that has become a scientific research tool in many fields. Overfitting is a common challenge in machine learning, where the model fits the training data too well and performs poorly on new data. Stochastic regularization is one method used to prevent overfitting, by artificially constraining the model to be simpler. In this thesis, we investigate the use of tools from information and coding theory as regularization methods in machine learning. The motivation for this project comes from recent results that successfully related generalization capability of learning algorithms to the information stored in the model parameters. This has led us to explore the use of stochastic regularization techniques like Dropout and DropConnect, which add sparsity to the networks and can help control and limit the information that the parameters store on the training data. Specifically, we explore the use of parity-check matrices from coding theory as masks in the DropConnect method. Parity-check matrices describe linear relations that codewords must satisfy, and have been shown to perform well as measurement matrices in compressed sensing. We build a new family of neural networks that apply Low-Density Parity-Check (LDPC) matrices as DropConnect masks, so-called Low-Density Parity-Check DropConnect (LDPC DropConnect). We evaluate the performance of this neural network with popular datasets in classification and track the generalization capability with statistics of the LDPC matrices. Our experiments show that adopting LDPC matrices does not significantly improve the generalization performance, but it helps provide a more robust evidence lower bound in the Bayesian approach. Our work may provide insights for further research on applying machine learning in compressed sensing, distributed computation, and other related areas. / Maskininlärning är ett populärt ämne som har blivit ett vetenskapligt forskningsverktyg inom många områden. Overfitting är en vanlig utmaning inom maskininlärning, där modellen anpassar sig till träningsdatan för bra och presterar dåligt på nya data. Stokastisk regularisering är en metod som används för att förhindra överanpassning, genom att artificiellt begränsa modellen till att vara enklare. I detta examensarbete undersöker vi användningen av verktyg från informations och kodningsteorin som regulariseringsmetoder inom maskininlärning. Motivationen för detta projekt kommer från nya resultat som framgångsrikt relaterade generaliseringsförmågan hos inlärningsalgoritmer till informationen som lagras i modellparametrarna. Detta har lett oss till att utforska användningen av stokastiska regulariseringstekniker som Dropout och DropConnect, som leder till glesa nätverken och kan hjälpa till att kontrollera och begränsa informationen som parametrarna lagrar am träningsdatan. Specifikt utforskar vi användningen av paritetskontrollmatriser från kodningsteori som masker i DropConnect-metoden. Paritetskontrollmatriser beskriver linjära relationer som kodord måste uppfylla, och har visat sig fungera bra som mätmatriser vid komprimerad avkänning. Vi bygger en ny familj av neurala nätverk som tillämpar low-density parity-check (LDPC)-matriser som DropConnect-masker, så kallade LDPC DropConnect. Vi utvärderar prestandan för detta neurala nätverk med populära datauppsättningar i klassificering och spårar generaliseringsförmågan med statistik över LDPC-matriserna. Våra experiment visar att antagandet av LDPC-matriser inte signifikant förbättrar generaliseringsprestandan, men det hjälper till att ge en mer robust bevis nedre gräns i den Bayesianska metoden. Vårt arbete kan ge insikter för ytterligare forskning om tillämpning av maskininlärning i komprimerad avkänning, distribuerad beräkning och andra relaterade områden.
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Quantitative NMR-Spektroskopie als Referenzverfahren in der analytischen ChemieMalz, Frank 10 July 2003 (has links)
Die Globalisierung von Handel und Wirtschaft macht es nötig, nationale Analysenergebnisse international gegenseitig anzuerkennen. Dabei kann die Richtigkeit der Analysenwerte durch Ruckführung auf Einheitsnormale mittels Primärmethoden, Zertifizierte Referenzmaterialien (ZRM) und Referenzverfahren gewährleistet werden. Die quantitative hochauflösende 1H-SP-NMR bietet sich aufgrund ihrer ausgezeichneten Selektivität und ihrem Potenzial als relative Primärmethode geradezu als Referenzverfahren an. Für vier wichtige Anwendungsbereiche (Bestimmung von Stoffmengenverhältnissen und -anteilen in mol/mol bzw. mol/mol %, der Reinheitsbestimmung über die Hauptkomponentenanalyse in g/g % und der Gehaltsbestimmung in mg/g) wurden anhand idealer Modellsysteme in Lösung (5-Komponenten: Ethyl-4-toluolsulfonat, [2,2]-Paracyclophan, Durol, Cyclododekan, Oktamethylcyclotetrasiloxan; Maleinsäure; 3-Trimethyl-2,2,3,3-tetradeuteropropionsäure-Natriumsalz (TSP)) die Messgleichungen und vollständigen Unsicherheitsbudgets aufgestellt sowie Arbeitsanweisungen zur quantitativen Aufnahme und Auswertung von 1H-NMR-Messungen erarbeitet. Dazu war für die Reinheits- und Gehaltsbestimmung ein System interner NMR-Standards aufzubauen (ZRM Benzoesäure, Maleinsäure, TSP-Lösung, Durol), das den Forderungen nach metrologischer Rückführung genügte. Zur Minimierung der Messunsicherheit wurden systematisch die Einflüsse gerätespezifischer Parameter und der Auswertung umfangreich untersucht und quantifiziert. Mittels mitorganisierter nationaler und internationaler CCQM-Ringversuche konnten allgemeingültige (unabhängig von der Gerätekonfiguration) Aussagen über die Messunsicherheit der Methoden bzw. Verfahren getroffen werden. Für realitätsbezogene Fragestellungen der Reinheitsbestimmung möglicher Referenzmaterialien für den pharmazeutischen Bereich (Spiraeosid, Thymol, Loganin) sowie von Xylol-Isomeren-Gemischen und der Gehaltsbestimmung 0,1%-iger wässriger Ethanollösungen mussten teilweise die quantitative 1H-entkoppelte 13C-NMR validiert und der quantitative Einsatz der 1H-Wasserunterdrückung (Presaturation) erstmalig entwickelt werden. Um die Güte der quantitativen NMR-Verfahren als Referenzverfahren bewertet zu können, wurde durch Beteiligung an internationalen Ringversuchen auf höchstem metrologischen Niveau (CCQM) deren Messunsicherheiten mit denen anderer analytischer Verfahren verglichen. Es konnten somit vier Referenzverfahren durch Dokumentation der Prüfbereiche, Messunsicherheiten und Einsatzgebiete der quantitativen hochauflösenden 1H- und 13C-NMR formuliert werden. / The globalisation of trade and economics makes requires mutual international recognition of analytical measurement results. The trueness of analytical results can be secured by establishing traceability to measurement standards for SI units using primary methods, certified reference materials (CRM) and reference methods. The quantitative high resolution 1H-SP-NMR offers itself as reference method due to its excellent selectivity and its potential as relative primary method. For four important areas of application (determination of amount-of-substance ratios and fractions in mol/mol and mol/mol %, respectively, purity determination by main component analysis in g/g %, and determination of minor component mass fractions in mg/g) the measuring equations and complete uncertainty budgets were set up, and work instructions for the acquisition and evaluation of quantitative 1H-NMR measurements were compiled, on the basis of ideal model systems in solution (5 components: Ethyl-4-toluenesulfonate, [2,2]-Paracyclophane, Durene, Cyclododecane, Octamethylcyclotetrasiloxane; Maleic acid; 3-Trimethyl-2,2,3,3-tetradeuteropropionic acid sodium salt (TSP)). In addition, a system of internal NMR standards had to be built up (CRM benzoic acid, maleic acid, TSP solution, Durene) for the determination of composition and purity, which meets the demands for metrological traceability. For the minimization of measurement uncertainty, the influences of instrument-specific parameters and data evaluation techniques were extensively examined and quantified. By means of national and jointly organized international CCQM intercomparisons generally applicable statements (independent of the measuring system configuration) about the measurement uncertainty for the different methods could be specified. For addressing real-life problems in purity determination of prospective reference substances for the pharmaceutical field (spiraeoside, thymol, loganin) as well as of xylene isomer mixtures and the analysis of 0,1 % aqueous ethanol solutions, the quantitative 1H-decoupled 13C-NMR had to be validated in part and the quantitative application of the 1H water suppression (presaturation) was developed for the first time. In order to estimate the power of quantitative NMR as a reference method, measurement uncertainties were compared with those of other analytical methods by participation in international intercomparisons on the highest metrological level (CCQM). Thus, four reference methods of the quantitative high resolution 1H- and 13C-NMR could be specified in terms of measuring ranges, measurement uncertainties and application fields.
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Desenvolvimento e validação de metodologia analítica para análise de aços por espectrometria de fluorescência de raios X por dispersão de energia (EDXRF)Krummenauer, Alex January 2017 (has links)
O desenvolvimento e validação de métodos analíticos é um procedimento necessário quando um método não normalizado é utilizado por um laboratório de ensaios. A validação de métodos também é um requisito específico da norma ABNT NBR ISO/IEC 17025, que determina os requisitos gerais para a competência dos laboratórios de ensaio e calibração. O objetivo da validação é demonstrar que o método analítico, nas condições em que é executado, produz resultados com a exatidão requerida. O Laboratório de Corrosão, Proteção e Reciclagem de Materiais (LACOR), da UFRGS, tem o ensaio de determinação de metais por fluorescência de raios X, acreditado pelo CGCRE/INMETRO, conforme ABNT NBR ISO/IEC 17025. O ensaio é feito usando o método de espectrometria de fluorescência de raios X por dispersão de energia (EDXRF). Este método, contudo, não é normalizado e, portanto, o mesmo foi validado, neste trabalho de pesquisa, para atender a este requisito. A validação foi feita com base no documento orientativo DOQ-CGCRE-08 e no guia EURACHEM. Os parâmetros de validação, para o ensaio quantitativo por EDXRF, que foram calculados neste trabalho são: seletividade; limite de detecção (LD) e limite de quantificação (LQ); linearidade e faixa de trabalho; veracidade de medição (tendência, erro normalizado, Z-score e comparação com método de referência) e precisão (repetibilidade, precisão intermediária e reprodutibilidade). Além disso, foi desenvolvida uma metodologia de cálculo de incerteza de medição para o ensaio por EDXRF Os resultados obtidos neste estudo demonstram que o método EDXRF, usado na determinação de metais em aços, é um método não normalizado validado e compatível com os resultados obtidos com os métodos de referência: espectrometria de fluorescência de raios X por dispersão de comprimento de onda (WDXRF), fotométricos e espectrometria de absorção atômica (AAS). Inclusive, o WDXRF é um método de referência usado em muitas normas internacionais, que descrevem métodos de análise de aços por fluorescência de raios X, como ASTM E572 ou ASTM E1085. O estudo desenvolvido nesta dissertação permitiu que o LACOR mantivesse sua acreditação no ensaio de determinação de metais por fluorescência de raios X, na avaliação do CGCRE/INMETRO, no presente ano. Outros frutos deste trabalho foram a confecção das curvas de calibração do espectrômetro NITON XL3t GOLDD+ e a revisão do procedimento de ensaio, onde esses novos conhecimentos sobre a técnica EDXRF foram aplicados. Futuramente, este trabalho pode ser usado por outros pesquisadores para desenvolver estudos em outras matrizes metálicas, como cobre, alumínio, titânio ou níquel, e, também, em outras áreas de aplicação como jóias, reciclagem de materiais metálicos ou, até mesmo, para análise elementar de resíduos retidos em membranas de troca iônica. / The development and validation of analytical methods is a required procedure when a non-standard method is used by a testing laboratory. Method validation is also a specific requirement of the ABNT NBR ISO / IEC 17025, which determines the general requirements for the competence of testing and calibration laboratories. The purpose of validation is to demonstrate that the analytical method, under the conditions in which it is performed, produces results with the required accuracy. The Corrosion, Protection and Recycling Materials Laboratory (LACOR), at UFRGS, has the X-ray fluorescence metal analysis, accredited by CGCRE / INMETRO, according to ABNT NBR ISO / IEC 17025. The test is performed using Energy Dispersive X-Ray Fluorescence spectrometry, EDXRF method. This method, however, is not standardized; therefore, it was validated in this research to meet this requirement. The validation was based on the DOQ-CGCRE-08 document and the EURACHEM guide. The method performance calculated in this study for quantitative testing by EDXRF are: selectivity; limit of detection (LOD) and limit of quantification (LOQ); linearity and working range; trueness (bias, normalized error, Z-score and comparison with reference method) and precision (repeatability, intermediate precision and reproducibility). In addition, a measurement uncertainty calculation methodology was developed for the EDXRF testing The results obtained in this study demonstrate that the EDXRF method, used in the determination in the chemical analysis of steels, is a validated non-standard method and compatible with the results obtained with the reference methods: Wavelength Dispersive X-Ray Fluorescence spectrometry (WDXRF), photometric and atomic absorption spectrometry (AAS). In addition, WDXRF is a reference method used in many international standards, which describes analysis of steels by X-ray fluorescence spectrometry such ASTM E572 or ASTM E1085. The study developed in this dissertation allowed LACOR to maintain its accreditation in the test of metal by X-ray fluorescence analysis, in the CGCRE / INMETRO audit, this year. Other fruits of this work were the preparation of calibration curves of NITON XL3t GOLDD + spectrometer and complete revision of testing procedure, where this new knowledge about the EDXRF technique was applied. In the future, this work can be used by other researchers to develop studies in other base metals such as copper, aluminum, titanium or nickel, and also in other areas of application such as jewelry, recycling of metallic materials or even for analysis elemental residues retained in ion exchange membranes.
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Desenvolvimento e validação de metodologia analítica para análise de aços por espectrometria de fluorescência de raios X por dispersão de energia (EDXRF)Krummenauer, Alex January 2017 (has links)
O desenvolvimento e validação de métodos analíticos é um procedimento necessário quando um método não normalizado é utilizado por um laboratório de ensaios. A validação de métodos também é um requisito específico da norma ABNT NBR ISO/IEC 17025, que determina os requisitos gerais para a competência dos laboratórios de ensaio e calibração. O objetivo da validação é demonstrar que o método analítico, nas condições em que é executado, produz resultados com a exatidão requerida. O Laboratório de Corrosão, Proteção e Reciclagem de Materiais (LACOR), da UFRGS, tem o ensaio de determinação de metais por fluorescência de raios X, acreditado pelo CGCRE/INMETRO, conforme ABNT NBR ISO/IEC 17025. O ensaio é feito usando o método de espectrometria de fluorescência de raios X por dispersão de energia (EDXRF). Este método, contudo, não é normalizado e, portanto, o mesmo foi validado, neste trabalho de pesquisa, para atender a este requisito. A validação foi feita com base no documento orientativo DOQ-CGCRE-08 e no guia EURACHEM. Os parâmetros de validação, para o ensaio quantitativo por EDXRF, que foram calculados neste trabalho são: seletividade; limite de detecção (LD) e limite de quantificação (LQ); linearidade e faixa de trabalho; veracidade de medição (tendência, erro normalizado, Z-score e comparação com método de referência) e precisão (repetibilidade, precisão intermediária e reprodutibilidade). Além disso, foi desenvolvida uma metodologia de cálculo de incerteza de medição para o ensaio por EDXRF Os resultados obtidos neste estudo demonstram que o método EDXRF, usado na determinação de metais em aços, é um método não normalizado validado e compatível com os resultados obtidos com os métodos de referência: espectrometria de fluorescência de raios X por dispersão de comprimento de onda (WDXRF), fotométricos e espectrometria de absorção atômica (AAS). Inclusive, o WDXRF é um método de referência usado em muitas normas internacionais, que descrevem métodos de análise de aços por fluorescência de raios X, como ASTM E572 ou ASTM E1085. O estudo desenvolvido nesta dissertação permitiu que o LACOR mantivesse sua acreditação no ensaio de determinação de metais por fluorescência de raios X, na avaliação do CGCRE/INMETRO, no presente ano. Outros frutos deste trabalho foram a confecção das curvas de calibração do espectrômetro NITON XL3t GOLDD+ e a revisão do procedimento de ensaio, onde esses novos conhecimentos sobre a técnica EDXRF foram aplicados. Futuramente, este trabalho pode ser usado por outros pesquisadores para desenvolver estudos em outras matrizes metálicas, como cobre, alumínio, titânio ou níquel, e, também, em outras áreas de aplicação como jóias, reciclagem de materiais metálicos ou, até mesmo, para análise elementar de resíduos retidos em membranas de troca iônica. / The development and validation of analytical methods is a required procedure when a non-standard method is used by a testing laboratory. Method validation is also a specific requirement of the ABNT NBR ISO / IEC 17025, which determines the general requirements for the competence of testing and calibration laboratories. The purpose of validation is to demonstrate that the analytical method, under the conditions in which it is performed, produces results with the required accuracy. The Corrosion, Protection and Recycling Materials Laboratory (LACOR), at UFRGS, has the X-ray fluorescence metal analysis, accredited by CGCRE / INMETRO, according to ABNT NBR ISO / IEC 17025. The test is performed using Energy Dispersive X-Ray Fluorescence spectrometry, EDXRF method. This method, however, is not standardized; therefore, it was validated in this research to meet this requirement. The validation was based on the DOQ-CGCRE-08 document and the EURACHEM guide. The method performance calculated in this study for quantitative testing by EDXRF are: selectivity; limit of detection (LOD) and limit of quantification (LOQ); linearity and working range; trueness (bias, normalized error, Z-score and comparison with reference method) and precision (repeatability, intermediate precision and reproducibility). In addition, a measurement uncertainty calculation methodology was developed for the EDXRF testing The results obtained in this study demonstrate that the EDXRF method, used in the determination in the chemical analysis of steels, is a validated non-standard method and compatible with the results obtained with the reference methods: Wavelength Dispersive X-Ray Fluorescence spectrometry (WDXRF), photometric and atomic absorption spectrometry (AAS). In addition, WDXRF is a reference method used in many international standards, which describes analysis of steels by X-ray fluorescence spectrometry such ASTM E572 or ASTM E1085. The study developed in this dissertation allowed LACOR to maintain its accreditation in the test of metal by X-ray fluorescence analysis, in the CGCRE / INMETRO audit, this year. Other fruits of this work were the preparation of calibration curves of NITON XL3t GOLDD + spectrometer and complete revision of testing procedure, where this new knowledge about the EDXRF technique was applied. In the future, this work can be used by other researchers to develop studies in other base metals such as copper, aluminum, titanium or nickel, and also in other areas of application such as jewelry, recycling of metallic materials or even for analysis elemental residues retained in ion exchange membranes.
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Desenvolvimento e validação de metodologia analítica para análise de aços por espectrometria de fluorescência de raios X por dispersão de energia (EDXRF)Krummenauer, Alex January 2017 (has links)
O desenvolvimento e validação de métodos analíticos é um procedimento necessário quando um método não normalizado é utilizado por um laboratório de ensaios. A validação de métodos também é um requisito específico da norma ABNT NBR ISO/IEC 17025, que determina os requisitos gerais para a competência dos laboratórios de ensaio e calibração. O objetivo da validação é demonstrar que o método analítico, nas condições em que é executado, produz resultados com a exatidão requerida. O Laboratório de Corrosão, Proteção e Reciclagem de Materiais (LACOR), da UFRGS, tem o ensaio de determinação de metais por fluorescência de raios X, acreditado pelo CGCRE/INMETRO, conforme ABNT NBR ISO/IEC 17025. O ensaio é feito usando o método de espectrometria de fluorescência de raios X por dispersão de energia (EDXRF). Este método, contudo, não é normalizado e, portanto, o mesmo foi validado, neste trabalho de pesquisa, para atender a este requisito. A validação foi feita com base no documento orientativo DOQ-CGCRE-08 e no guia EURACHEM. Os parâmetros de validação, para o ensaio quantitativo por EDXRF, que foram calculados neste trabalho são: seletividade; limite de detecção (LD) e limite de quantificação (LQ); linearidade e faixa de trabalho; veracidade de medição (tendência, erro normalizado, Z-score e comparação com método de referência) e precisão (repetibilidade, precisão intermediária e reprodutibilidade). Além disso, foi desenvolvida uma metodologia de cálculo de incerteza de medição para o ensaio por EDXRF Os resultados obtidos neste estudo demonstram que o método EDXRF, usado na determinação de metais em aços, é um método não normalizado validado e compatível com os resultados obtidos com os métodos de referência: espectrometria de fluorescência de raios X por dispersão de comprimento de onda (WDXRF), fotométricos e espectrometria de absorção atômica (AAS). Inclusive, o WDXRF é um método de referência usado em muitas normas internacionais, que descrevem métodos de análise de aços por fluorescência de raios X, como ASTM E572 ou ASTM E1085. O estudo desenvolvido nesta dissertação permitiu que o LACOR mantivesse sua acreditação no ensaio de determinação de metais por fluorescência de raios X, na avaliação do CGCRE/INMETRO, no presente ano. Outros frutos deste trabalho foram a confecção das curvas de calibração do espectrômetro NITON XL3t GOLDD+ e a revisão do procedimento de ensaio, onde esses novos conhecimentos sobre a técnica EDXRF foram aplicados. Futuramente, este trabalho pode ser usado por outros pesquisadores para desenvolver estudos em outras matrizes metálicas, como cobre, alumínio, titânio ou níquel, e, também, em outras áreas de aplicação como jóias, reciclagem de materiais metálicos ou, até mesmo, para análise elementar de resíduos retidos em membranas de troca iônica. / The development and validation of analytical methods is a required procedure when a non-standard method is used by a testing laboratory. Method validation is also a specific requirement of the ABNT NBR ISO / IEC 17025, which determines the general requirements for the competence of testing and calibration laboratories. The purpose of validation is to demonstrate that the analytical method, under the conditions in which it is performed, produces results with the required accuracy. The Corrosion, Protection and Recycling Materials Laboratory (LACOR), at UFRGS, has the X-ray fluorescence metal analysis, accredited by CGCRE / INMETRO, according to ABNT NBR ISO / IEC 17025. The test is performed using Energy Dispersive X-Ray Fluorescence spectrometry, EDXRF method. This method, however, is not standardized; therefore, it was validated in this research to meet this requirement. The validation was based on the DOQ-CGCRE-08 document and the EURACHEM guide. The method performance calculated in this study for quantitative testing by EDXRF are: selectivity; limit of detection (LOD) and limit of quantification (LOQ); linearity and working range; trueness (bias, normalized error, Z-score and comparison with reference method) and precision (repeatability, intermediate precision and reproducibility). In addition, a measurement uncertainty calculation methodology was developed for the EDXRF testing The results obtained in this study demonstrate that the EDXRF method, used in the determination in the chemical analysis of steels, is a validated non-standard method and compatible with the results obtained with the reference methods: Wavelength Dispersive X-Ray Fluorescence spectrometry (WDXRF), photometric and atomic absorption spectrometry (AAS). In addition, WDXRF is a reference method used in many international standards, which describes analysis of steels by X-ray fluorescence spectrometry such ASTM E572 or ASTM E1085. The study developed in this dissertation allowed LACOR to maintain its accreditation in the test of metal by X-ray fluorescence analysis, in the CGCRE / INMETRO audit, this year. Other fruits of this work were the preparation of calibration curves of NITON XL3t GOLDD + spectrometer and complete revision of testing procedure, where this new knowledge about the EDXRF technique was applied. In the future, this work can be used by other researchers to develop studies in other base metals such as copper, aluminum, titanium or nickel, and also in other areas of application such as jewelry, recycling of metallic materials or even for analysis elemental residues retained in ion exchange membranes.
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Testovací metody pro hodnocení radiačních efektů v přesných analogových a signálově smíšených obvodech pro aplikace v kosmické elektronice / Test Methods for Evaluation of Radiation Effects in High Precision Analog and Mixed-Signal Devices for Space ApplicationsHofman, Jiří January 2019 (has links)
The traditional radiation testing of space electronics has been used for more than fifty years to support the radiation hardness assurance. Its typical goal is to ensure reliable operation of the spacecraft in the harsh environment of space. This PhD research looks into the radiation testing from a different perspective; the goal is to develop radiation testing methods that are focused not only on the reliability of the components but also on a continuous radiation-induced degradation of their performance. Such data are crucial for the understanding of the impact of radiation on the measurement uncertainty of data acquisition systems onboard research space missions.
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Návrh vhodného etalonu délky pro nano-CT měřicí přístroj / Design of a suitable length standard for nanp-CT measuring deviceKožiol, 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.
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Skener elektromagnetických polí a jeho využití při měření elektromagnetické kompatibility / Electromagnetic field scanner and its utilization in EMC measurementChupáč, Michal January 2013 (has links)
Master’s thesis is focused on making the acquaintance of EMC issues and ways of electromagnetic field scanner RS321 utilization for pre-compliance measurements. First part contains analysis of available equipment’s influence on measurement results on the basis of gathered specification. Next part includes an example measurement used as operational manual for scanner and its controlling program. The most important part is correction evaluation for performed EMI measurement of signal generator using its EMC certification protocol and application of gained correction curve on independent EMI measurement of device tested by EMC testing laboratory. Other possibilities of scanner utilization are mentioned in the next chapters. Last part of the thesis contains suitability evaluation of EMC scanner on the basis of findings from performed measurements.
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Kvantifikace nejistot měření magnetických veličin / Measurement of magnetic quantities - estimation of the uncertaintyŠlichta, Pavol January 2016 (has links)
This Master’s thesis contains an overview of determining measurement uncertainties of direct and indirect measurements. It describes a way of creating a magnetic field with the help of Helmholtz coil and a more detailed description of some principles of magnetic field sensors. This thesis also contains a description of the experiments and the factors influencing them. The last part deals with the quantification of uncertainties from measured experiments and with the discussion of the results from these measurements.
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