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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.
41

Nejistoty interferometrických měření / Uncertainties in interferometric measurements

Kočí, Radek January 2014 (has links)
This diploma thesis deals with uncertainties of interferometric measurements and methods for their evaluation. In the theoretical part of the thesis, are described interferometers and interferometric measurement techniques. Furthermore, there is presented process of determining the measurement uncertainty using methods GUM and Monte Carlo. In the practical part of the thesis, there are these two methods are used for qualification of measurement uncertainty calculated for the specific interferometer.
42

ANALÝZA ZPŮSOBILOSTI VÝROBNÍHO STROJE PŘI VÝROBĚ AUTOBUSŮ / ANALYZIS OF THE PROCESSING MACHINE CAPABILITY IN BUS PRODUCTION

Gregor, Jaroslav January 2008 (has links)
The diploma thesis deals with an analysis of the processing machine capability in bus production. The goal is to evaluate the capability of the CNC laser processing machine in conditions of Iveco Czech Republic, Ltd., Vysoke Myto. In the theoretical part, the thesis studies measurements and capability of the processing machine; the practical part describes the present state of production and suggests a solution of the assigned task.
43

Výpočet emisní hodnoty při měření akustického tlaku a výkonu / Calculation of emission value in measurement of acoustic pressure and capacity

Málek, Michal January 2008 (has links)
The conceptions in acoustics. The description of the methods measurement of the noise mechanical equipment. The express the uncertainty of measurement. The analyse and determination basic emission values of acoustic pressure and power. The summary of results and programming of the calculation basic emission values acoustic pressure and power for fine implementation measurement.
44

Analýza kontroly klopného momentu axiálního táhla řízení / Analysis verification monostable moment longitudinal steering linkage

Novotný, Petr January 2010 (has links)
Work smoothing - out evaluation accuracy of measurement monostable moment steering linkage by the help of special machine. Evaluates individual characteristics accuracy, especially uncertainty metering.
45

[en] SOLID SUBSTRATE ROOM-TEMPERATURE PHOSPHORIMETRY FOR THE IRINOTECAN HYDROCHLORIDE DETERMINATION, ACTIVE PRINCIPLE OF INJECTABLE ANTI-CANCER DRUGS, AND TRACES OF CONTAMINANTS IN PHARMACEUTICAL FORMULATIONS CAMPTOTHECIN ANTI-CANCER / [pt] FOSFORIMETRIA NA TEMPERATURA AMBIENTE EM SUBSTRATO SÓLIDO PARA DETERMINAÇÃO DO CLORIDRATO DE IRINOTECANA, E TRAÇOS DO CONTAMINANTE CAMPTOTECINA EM FORMULAÇÕES FARMACÊUTICAS ANTICÂNCER

PRISCILA MARIANA DA SILVA MAIA 16 May 2019 (has links)
[pt] Os derivados da camptotecina (CPT), irinotecana (CPT-11) e topotecana (TPT) são usados para o tratamento do câncer, sendo a CPT um potencial contaminante em medicamentos anticâncer a base de CPT-11 ou TPT. Neste trabalho, a fosforimetria na temperatura ambiente em substrato sólido (SSRTP) foi proposta como técnica analítica para a determinação do princípio ativo do anticâncer injetável a base de CPT-11 e de traços do contaminante CPT em formulações farmacêuticas anticâncer. As características fosforescentes dos dois analitos foram estudadas de modo univariado em função de diversos parâmetros experimentais, como o tipo e a quantidade de sal de átomo pesado indutor de fosforescência, influência do valor do pH do tampão usado na solução do analito e quantidade de surfactante modificador de superfície da celulose. Uma vez definidos os fatores relevantes, o planejamento fatorial do tipo composto central foi realizado para a determinação de traços do contaminante (CPT) com o intuito de estudar os efeitos principais e as possíveis interações entre os fatores de resposta visando à escolha da melhor condição experimental. As melhores condições foram obtidas usando substratos de celulose contendo 332 microgramas de TlNO3 (indutor da fosforescência) em solução carreadora contendo tampão Britton-Robinson (pH 10,5). Para a CPT-11 a otimização foi realizada apenas pela abordagem univariada, com as seguintes condições escolhidas: 662 microgramas de Pb(NO3)2 em substratos de celulose contendo 577 microgramas de SDS. A CPT pôde ser determinada seletivamente em matrizes contendo 40 vezes mais TPT, em concentração, usando a determinação no ponto isodiferencial (367 nm) da derivada de segunda ordem do espectro de excitação. Para matrizes contendo CPT-11, esse desempenho foi mais limitado, pois a CPT só foi determinada seletivamente em misturas contendo até 5 vezes mais CPT-11. Para cada uma das condições selecionadas foram realizados estudos para obtenção dos parâmetros de desempenho. Em ambos os casos, a resposta analítica teve comportamento linear (homocedático) em função da massa de CPT ou de CPT-11 presentes no substrato de celulose. Os limites de detecção e de quantificação absolutos ficaram na ordem do ng. Um estudo detalhado da estimativa da incerteza de medição também foi realizado e a incerteza combinada associada à medição de fosforescência da CPT foi de até 16 por cento. O método foi aplicado na quantificação de CPT-11 em soluções injetáveis com 97,5 mais ou menos 5,5 por cento de recuperação e na determinação de CPT em medicamentos a base de TPT (101,5 mais ou menos 3,5 por cento de recuperação medindo em 367 nm do espectro de excitação após derivação de segunda ordem) e nas matrizes urina (102,5 mais ou menos 3,5 por cento de recuperação) e saliva (102,5 mais ou menos 4,5 por cento de recuperação), ambas fortificadas com CPT e usando-se detecção em 570 nm do espectro de emissão de varredura normal. Testes comparativos entre a SSRTP e a HPLC-DF foram realizados e os resultados foram satisfatórios para um nível de 95 por cento de confiança. Uma comparação entre diferentes substratos foi também realizada para avaliar requisitos práticos, variabilidade de sinal do analito e do branco, o que indicou vantagens do substrato de nylon sobre o de celulose. / [en] Irinotecan (CPT-11) and topotecan (TPT) are employed for cancer treatment and camptothecin (CPT) is a potential contaminant in anti-cancer drugs based on CPT-11 or TPT. In this work, solid substrate room-temperature phosphorimetry (SSRTP) was proposed as analytical technique for the quantification of CPT-11 in anti-cancer drugs and for the determination of traces of CPT in CPT-11 and TPT based anti-cancer pharmaceutical formulations. The phosphorescence characteristics of the analytes have been studied and experimental conditions (type and amount of the heavy atom salts used to induce phosphorescence, influence of the pH of the analyte carrier solution and the amount of surface modifier) were optimized in an univariate way. For the method aiming the determination of CPT, a further optimization using a central composite design was made in order to identify the main effects and possible interactions among factors. The best conditions had been achieved using cellulose substrate containing 332 micrograms of TlNO3 (phosphorescence inducer) and analyte carrier solution containing Britton-Robinson buffer (pH 10.5). For the CPT-11, best conditions were achieved in cellulose substrates containing 577 micrograms of SDS and 662 micrograms of Pb(NO3)2 The selective determination of CPT could be performed in samples containing a higher amount of TPT (40 times) if the signal measurement is made at the isodifferential wavelength (367 nm) of the second derivative excitation spectra. For samples containing CPT-11, selective determination of CPT could be made in samples containing CPT-11/CPT molar proportion no higher than 5. Parameters of merit have been obtained for both methods. Analytical responses presented linear behavior in the in working range from the limit of quantification up to at least 348.0 ng of CPT or 440.2 ng of CPT-11 (deposited in the center of the substrate). Absolute limits of detection and quantification were 26.8 and 42.3 ng for CPT and 79.6 and 99.9 ng for CPT-11. A detailed metrological study was performed for the measurement of CPT and the combined uncertainty associated to the phosphorescence measurement was 16 percent. The method was applied for the quantification of CPT-11 in injectable solutions with recovery of 97.5 more or less 5.5 percent. For CPT, recovery in TPT based pharmaceutical formulation, previously fortified with the analyte, was 101.5 more or less 3.5 percent (measurement made at 367 nm of the second derivative excitation spectra). In analyte fortified urine and saliva, recoveries were respectively 102.5 more or less 3.5 percent and 102.5 more or less 4.5 percent (using non-derived spectra and detention at 570 nm of the emission band). Comparative tests between the SSRTP and HPLC-DF have been made and the results agreed (at a 95 percent confidence level). A comparison using different substrates (nylon and cellulose) was also performed in order to evaluate practical aspects, analyte signal intensity and the variability of the analyte and blank signals. The result indicated advantages in using nylon substrates for the phosphorimetric determination of CPT.
46

Métodos espectrofotométrico, RP-UPLC e microbiológico para determinação de linezolida em formas farmacêuticas / Spectrophotometric, RP-UPLC and microbiological methods for determination of linezolida in pharmaceutical preparations

Saviano, Alessandro Morais 23 October 2015 (has links)
A linezolida é um antibiótico oxazolidinona efetivo contra bactérias patogênicas gram-positivas, incluindo Staphylococcus aureus resistente a meticilina (MRSA), Staphylococcus aureus resistente a glicopeptídeos (GISA) e enterococci resistente a vancomicina (VRE). As oxazolidinonas inibem a translação bacteriana na fase de iniciação da síntese de proteínas, enquanto que a síntese de RNA e DNA não são afetadas. Diversos métodos por cromatografia líquida de alta-eficiência (HPLC) têm sido relatados para a determinação da concentração de linezolida em plasma humano, soro e urina. Entretanto, um número pequeno de métodos estão disponíveis para a determinação de linezolida em formulações farmacêuticas. O objetivo deste trabalho foi desenvolver e validar métodos espectrofotométrico, de cromatografia líquida de ultraeficiência em fase reversa (RP-UPLC), doseamento microbiológico em placas e doseamento microbiológico rápido em microplacas com leitura cinética para a determinação de linezolida em soluções injetáveis e comprimidos. Adicionalmente, foram identificadas e quantificadas as principais fontes de incerteza relacionadas aos métodos. O desenvolvimento dos métodos utilizou uma abordagem racional, empregando-se planejamento de experimentos (análise fatorial e metodologia de superfície resposta) para otimização das condições analíticas. As fontes de incertezas foram identificadas empregando-se diagrama de Ishikawa e quantificadas conforme procedimento da Eurachem/Citac. Os métodos desenvolvidos apresentaram especificidade/seletividade, linearidade, precisão, exatidão e robustez adequadas, conforme os critérios estabelecidos pelo ICH e ANVISA. A análise estatística demonstrou equivalência entre os resultados providos por cada um dos métodos, sendo intercambiáveis entre si. Portanto, os métodos podem ser empregados no controle de qualidade de rotina na indústria farmacêutica. / Linezolid is an oxazolidinone antibiotic effective against gram-positive pathogenic bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), glycopeptide-intermediate Staphylococcus aureus (GISA) and vancomycin-resistant enterococci (VRE). Oxazolidinones inhibit bacterial translation at the initiation phase of protein synthesis, while RNA and DNA synthesis are not affected. Several high performance liquid chromatographic (HPLC) methods have been reported to determine the concentration of linezolid in human plasma, serum and urine. However, a few number of methods are available to determine the concentration of linezolid in pharmaceutical dosage forms. The aim of the present work was to develop and validate a spectrophotometric method, a reverse-phase ultra-high performance liquid chromatographic method, microbiological assay and microbiological rapid assay in microplates using kinetic reading for the determination of linezolid in injections and tablets dosage forms. In addition, the most important sources of uncertainty were identified and quantified for each method. A rational approach was used in the development of these methods, using design of experiments (factorial design and response surface methodology) for optimization of analytical conditions. The sources of uncertainties were identified using Ishikawa diagram and quantified as described in Eurachem/Citac procedure. The developed methods were specific/selective, linear, precise, accurate and robust, as required by ICH and ANVISA guidelines. Statistical analysis showed equivalence among the results provided by each method, being interchangeable. Thus, the methods may be employed in routine quality control analysis by pharmaceutical industry.
47

Procena merne nesigurnosti pri merenju ravnosti na koordinatnoj mernoj mašini primenom Monte Karlo simulacije / Estimation of Measurement Uncertainty in Measuring Flatness on aCoordinate Measuring Machine by Means of Monte Carlo Simulation

Štrbac Branko 26 May 2017 (has links)
<p>Koordinatne merne mašine (KMM) su dominantni merni instrumenti u<br />dimenzionalnoj metrologiji. NJihovom upotrebom se može izmeriti<br />bilo koja makro tolerancija označena na tehničkoj dokumentaciji.<br />Tolerancija ravnosti je često prisutna u cilju izvršenja zahtevanih<br />funkcionalnih zahteva radnog predmeta. Istraživanja sprovedena u<br />ovom radu se bave problemom procene greške ravnosti merene na KMM<br />zasnovane na metodi minimalne zone i procene merne nesigurnosti za<br />ovaj merni zadakat. Aksenat je stavljen na primeni Monte Karlo<br />metode kao simulacionog alata za procenu merne nesigurnosti.<br />Razvijena je nova metodologija za procenu greške ravnosti kao i<br />simulacioni model za procenu merne nesigurnosti za ovaj merni<br />zadatak.</p> / <p>Coordinate measuring machines (CMMs) are dominant measuring<br />instruments in dimensional metrology. These machines can measure any<br />macro-tolerance indicated in the technical documentation. Flatness tolerance<br />is often present with the aim of completing the needed functional<br />requirements of a workpiece. The investigation conducted in this paper<br />considers the problem of assessing the flatness error measured on a CMM<br />based on the minimum zone method and on the method of evaluating<br />measurement uncertainty for this measuring task. The emphasis is on the<br />use of Monte Carlo method as a simulation tool for evaluating measurement<br />uncertainty. A new methodology for assessing the flatness error has been<br />developed, as well as a simulation model for evaluating measurement<br />uncertainty for this measuring task.</p>
48

Posouzení metody stanovení průtoku jímáním kapaliny do odměrné nebo vážicí nádoby / Method analysis for flow measurement by collecting fluid into the volumetric or weighing vessel

Valdová, Klára January 2016 (has links)
This diploma thesis is concerned with assessment of two methods of gauging the flow rate used in the sphere of official measurements on profiles with an unrestricted water level. This is the method of collecting liquid into a volumetric vessel and the method of collecting liquid into a weighing vessel (pouch). The main purpose of this work was to specify uncertainties determined using method A and B for these two methods of gauging flow rate within the terms of addressing the Metrology Development Plan of the Czech Office for Standards, Metrology and Testing, because these uncertainties were previously determined using older methodology and using less accurate flow rate benchmarks. The entire work is based on extensive experimental measurement of the flow rate, using the assessed methods, executed at the Laboratory of Water Management Research in Brno. The method of collecting liquids into a volumetric vessel was assessed using four various vessel volumes - 9 l, 15 l, 30 l and 50 l. Relative uncertainties determined using method A and B in relation to flow rate are determined for each vessel in the experimental section of this work. Within the scope of this thesis, these uncertainties were also determined for the method of collection of liquid into weighing vessel (pouch), which was assessed for flow rates of from 0,5 l/s to 10,0 l/s.
49

Uncertainty in the first principle model based condition monitoring of HVAC systems

Buswell, Richard A. January 2001 (has links)
Model based techniques for automated condition monitoring of HVAC systems have been under development for some years. Results from the application of these methods to systems installed in real buildings have highlighted robustness and sensitivity issues. The generation of false alarms has been identified as a principal factor affecting the potential usefulness of condition monitoring in HVAC applications. The robustness issue is a direct result of the uncertain measurements and the lack of experimental control that axe characteristic of HVAC systems. This thesis investigates the uncertainties associated with implementing a condition monitoring scheme based on simple first principles models in HVAC subsystems installed in real buildings. The uncertainties present in typical HVAC control system measurements are evaluated. A sensor validation methodology is developed and applied to a cooling coil subsystem installed in a real building. The uncertainty in steady-state analysis based on transient data is investigated. The uncertainties in the simplifications and assumptions associated with the derivation of simple first principles based models of heat-exchangers are established. A subsystem model is developed and calibrated to the test system. The relationship between the uncertainties in the calibration data and the parameter estimates are investigated. The uncertainties from all sources are evaluated and used to generate a robust indication of the subsystem condition. The sensitivity and robustness of the scheme is analysed based on faults implemented in the test system during summer, winter and spring conditions.
50

Confiabilidade Metrológica: o caso da análise de DQO em um laboratório acadêmico. / Metrological Reliability: the case of the analysis of COD in an academic laboratory.

Érica Andrade Carvalho Mendez 11 April 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Desde 2004, o CONAMA (Conselho Nacional de Meio Ambiente), através de sua Resolução n 344, vem exigindo que as análises físicas, químicas e biológicas em matrizes ambientais sejam realizadas em laboratórios ambientais que possuam sua competência técnica reconhecida formalmente através da acreditação concedida pelo Inmetro. Assim, algumas Unidades Federativas vem adotando o mesmo critério para cadastramento de laboratórios em seus bancos de dados. Com isso, houve um crescimento no número de acreditações: em 2002 haviam 12 laboratórios acreditados e em 2012 foram concedidas 198 acreditações a laboratórios ambientais. A adoção da ABNT NBR ISO/IEC 17025 como padrão de trabalho, além de atender as legislações vigentes, possui as seguintes vantagens: satisfação do cliente, credibilidade e melhoria contínua do laboratório, melhoria da capacitação profissional e a conquista de um mercado mais amplo. Buscando adequar-se a essa realidade, apesar de todas as dificuldades inerentes ao processo de implementação dos requisitos da ABNT NBR ISO/IEC 17025 em laboratórios universitários e de pesquisa, o Laboratório de Engenharia Sanitária (LES/DESMA) priorizou a adequação da determinação da demanda química de oxigênio (DQO) aos requisitos técnicos da ABNT NBR ISO/IEC 17025:2005, por ser um parâmetro indicador global de matéria orgânica em águas residuárias e superficiais e ser amplamente utilizado no monitoramento de estações de tratamento de efluentes líquidos e pelo fato deste poder ser determinado por duas técnicas analíticas distintas: espectrofotometria e colorimetria. Em razão deste cenário, o objetivo deste trabalho foi avaliar o desempenho dos métodos 5220 B e 5220 D descritos pelo Standard Methods, através dos parâmetros de validação de métodos analíticos. Ambos os métodos mostraram-se adequados ao uso a que se destinam e o limite de quantificação determinado apresentou-se compatível com o praticado com os laboratórios acreditados. As incertezas foram calculadas de forma a quantificar a qualidade do resultado. / Since 2004, CONAMA - National Council for the Environment - through its Resolution No. 344, has demanded that the physical, chemical and biological environmental matrices are performed in environmental laboratories that have formally acknowledged their technical competence through accreditation granted by Inmetro. Since then, some Federal Units has adopted the same criteria for laboratories registration in their databases. With that, there was an increase in the number of accreditations: in 2002 there were 12 accredited laboratories and in 2012 were granted accreditation to 198 environmental laboratories. The adoption of ABNT NBR ISO / IEC 17025 as the standard of work, in addition to attend the existing laws, has the following advantages: customer satisfaction, continuous improvement and credibility of the lab, professional skills improvement and the gain of a broader market. Seeking to adapt to this reality, despite of all the difficulties inherent in the process of implementing the requirements of ABNT NBR ISO / IEC 17025 in university and research laboratories, the Laboratory of Sanitary Engineering - LES / DESMA - prioritized to determine the suitability of Chemical Oxygen Demand - COD to the technical requirements of ABNT NRB ISO / IEC 17025:2005, as a global indicator parameter of organic matter in wastewater and surface and be widely used in monitoring liquid effluent treatment stations and because this it can be determined by two different analytical techniques: colorimetry and spectrophotometry. Given this scenario, the objective of this study was to evaluate the performance of the methods 5220 B and 5220 D described by Standard Methods, using validation parameters of analytical methods. Both methods proved to be suitable for the intended use and the limit of quantification determined appeared to be compatible with the practiced with accredited laboratories. The uncertainties were calculated to quantify the quality of the result.

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