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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.
11

Kalibrace tlakoměrů / Calibration of pressure gauges

Schwarz, Jakub January 2014 (has links)
This diploma thesis is dealing with pressure measurement. It describes instruments dedicated to purpose - pressure gauges. Basic of correct pressure measurement is knowledge of behaviour of used pressure gauge. This knowledge is acquired by calibration. With calibration is associated also analysis of errors and uncertainty of measurement and creation of calibration list. Calibration takes place on model workspace pressure measuring in laboratory.
12

Uma metodologia para redu??o de incertezas em sistema de medi??o de vaz?o de ?leo e g?s

Ara?jo, Jo?o de Deus Freire de 20 March 2009 (has links)
Made available in DSpace on 2014-12-17T14:55:41Z (GMT). No. of bitstreams: 1 AraujoJDF_DISSERT.pdf: 2882504 bytes, checksum: 96c2fbb3f2a5321e6d6c3d365cb77eff (MD5) Previous issue date: 2009-03-20 / The objective of this research is to discuss about the need for implementation of new alternatives for the implementation on the metrological control: on the findings of initial and subsequent measurements, the control procedures of measurement uncertainty applied in assessing the loss or remains found in handling operations of bulk liquids, when used turbine meters used in measuring the tax on the business of Petrobras, due to the current environment of legal metrology and scientific, both domestic and international. We aim, with these alternatives: standardizing the minimization of random and systematic errors, the estimate of the remaining errors, as well as the management control of metrological calibration procedures, control of measurement uncertainty, and contribute to the change in the form of performance of legal metrology and scientific disseminating new information to change management of metrological control, objectively focused on aspects of supervision in implementing these activities in the control of the uncertainties of measurement used in our processes in the fiscal measurement system Petrobras. Results are presented, information and comments on the influence of measurement uncertainty in the current results of the fiscal and transfer of custody. This will emphasize the need, among other things, improvement and expansion of metrological control monitored by setting a better meet demand, calibration equipment and measuring instruments for Petrobras. Finally, we intend to establish the need for improving the method of evaluation of the data meter applied to the current management control of measurement uncertainty by proposing a methodology for addressing the problem, as well as highlighting the expected results. / O objetivo deste trabalho de pesquisa ? abordar a necessidade de implementa??o de novas alternativas para a execu??o da gest?o no controle metrol?gico: quanto ?s verifica??es das medi??es iniciais e posteriores; nos procedimentos de controle da incerteza de medi??o; aplicada na avalia??o das perdas ou sobras constatadas nas opera??es de movimenta??o de gran?is l?quidos; quando utilizamos medidores tipo turbina na medi??o fiscal utilizada nos neg?cios da Petrobras, em virtude ao atual cen?rio da metrologia legal e cient?fica; no contexto nacional e internacional. Almeja-se, com estas alternativas: padronizarmos a minimiza??o dos erros aleat?rios e sistem?ticos; a estimativa dos erros remanescentes; assim como, a gest?o no controle metrol?gico dos procedimentos de calibra??o; controle das incertezas de medi??es; e contribuirmos para a mudan?a na forma de atua??o da metrologia legal e cient?fica, divulgando novas informa??es para a gest?o de mudan?as do controle metrol?gico, voltadas objetivamente para os aspectos de supervis?o na execu??o destas atividades no controle das incertezas de medi??o utilizadas em nossos processos de medi??o fiscal no sistema Petrobras. S?o apresentados resultados, informa??es e coment?rios sobre a influ?ncia da incerteza de medi??o nos resultados atuais das medi??es fiscais e transfer?ncias de cust?dia. Isto enfatizar? a necessidade, dentre outras coisas, de melhoria e na amplia??o do controle metrol?gico monitorado, definindo um melhor atendimento ? demanda de calibra??es dos equipamentos e instrumentos de medi??es da Petrobras. Finalmente, pretende-se concluir pela necessidade do aprimoramento do m?todo de avalia??o dos dados do medidor aplicado na gest?o atual do controle de incertezas de medi??es, propondo metodologia para a abordagem do problema, assim como, destacando os resultados esperados.
13

建構一個供應鏈資訊分享機制:不確定構念之發展及虛擬整合之應用 / Forming an Information Sharing Mechanism in Supply Chains: A Development of Uncertainty Constructs and Application to Virtual Integration

戴逸民, Tai, Yi-Ming Unknown Date (has links)
供應鏈的運作過程包含一系列的價值創造活動,這些活動乃是由許多不同的組織所負責執行,且每個活動之間存在相互影響的關係。在這一牽涉跨組織合作的價值網絡中,所遭遇的困難主要是來自跨組織互動過程中所隱藏的不確定問題,而這些問題的產生主要導因於供應鏈夥伴間的活動缺乏調和。針對供應鏈分散管控結構所衍生出的問題,近年來以資訊科技為基礎的跨組織系統 (inter-organizational system, IOS)提供了有效的解決方案。此IOS的形成,主要是認為透過IOS的應用,供應鏈組織可藉由跨組織資訊分享的力量來改善夥伴間的協調以及資源整合。而此意謂IOS的效益產生端賴系統內建的資訊分享機制能相容於供應鏈結構特徵,並能有效協助組織來因應所面臨的不確定問題。是以,建立一個相容於環境的資訊分享機制是配置IOS解決方案過程的重要關鍵,且對於供應鏈不確定的診斷在資訊分享機制規劃過程有其重要性存在。 對於供應鏈不確定問題的診斷是一極為複雜且具挑戰的任務,其須要透過一結構化的框架來協助分析夥伴間錯綜複雜的互動行為過程所隱藏的不確定因素。因此,本研究乃採用結構化的方法來製作一符合統計效度的不確定因素衡量量表,並以此量表為工具透過個案研究的方法來探索收斂組裝型供應鏈,這一特定型態供應鏈所面臨的不確定問題。在了解供應鏈所面臨的不確定問題之後,本研究試圖針對此供應鏈型態提出一資訊分享機制規劃的參考架構,藉此架構引領供應鏈運作環境中的資訊科技規劃,並依此提升供應鏈整合。 在針對個案探討之後,本研究發現缺乏妥善規劃資訊分享機制是導致個案公司目前仍難以有效因應所面臨的不確定問題之主要原因。所施行的資訊分享實務與供應鏈環境間的不相容使得其目前仍難以有效因應需求的變異以及物料供給的管控。此外,本研究發現資訊分享模式會受到所面臨的不確定問題之屬性以及嚴重性程度的影響。在收斂組裝型供應鏈的案例中,受到供應鏈結構特徵的影響,資訊分享應著重於物料供給方面的議題。因為在該型態供應鏈運作環境中,供應端的夥伴結合相對於需求端而言較為複雜,且與領導廠商間的關係又非似需求端夥伴間來的密切。是以,在收斂組裝型供應鏈中,有必要投注較多的心力於建制與供應夥伴間的資訊分享。 / Supply chain management is a complicated task because of uncertainties involved. The uncertainty that occurs in the processes of inter-organizational coordination is due to a lack of harmony in supply chain participant activities. Recent developments in Inter-organizational Systems (IOS) have contributed to the provision of IT-based solutions for harmonizing supply chain participant activities. Applying IOS to the supply chain often attempts to improve the efficiency of coordination and resource integration among participants via inter-organizational information sharing. This intention implies that the effectiveness of IOS depends on whether information sharing mechanism built into the system can fit for supply chain characteristics and can help the supply chain cope with uncertainties that disrupt the integration of the supply chain. Hence, establishing an environment-suited information sharing mechanism is critical in deploying IOS solutions, and diagnosing supply chain uncertainties is important in planning information sharing mechanism. Diagnosing supply chain uncertainties is a complex and challenging task, it needs a structural framework to support in analyzing the intricacy of interactions among supply chain members, resulting in the construction of an instrument to assist in the understanding of uncertainty-related behaviors of supply chain participants. Therefore, this study takes a structural approach to produce a validated uncertainty scale, and applies a case study approach with this instrument to investigate the uncertainty problems in a specific supply chain type, convergent assembly supply chain. After understanding the uncertainty problems, this study proposed a reference model to assist this supply chain type in planning an information sharing mechanism, leading to a well-suited IT framework to improve supply chain integration. Falling short of a sounding information sharing mechanism is central to the problems in convergent assembly supply chain based upon the findings of case studies. The incompatibility between supply chain environment and existing information sharing practices has led to the problems in demand variation and material supply. Based on the characteristics of supply chain environment, planning inter-organizational coordination and information sharing simultaneously can effectively resolve the supply chain problems. Moreover, the research results suggested that the pattern of information sharing is influenced by the scale and severity of the uncertainty embedded in supply chain. In the case of convergent assembly supply chain, information sharing is focused on issues related to material supply owing to the structural characteristics of supply chain. The combination of participants in supply side is more complex and is not familiar with the leading company as demand side’s participants. Therefore, it needs to pay more attention for establishing information sharing among supply side’s participants.
14

Návrh interní metodiky pro měření výrobků a dílů na přístroji CMM UPMC Zeiss na pracovišti ČMI Brno / Proposal of internal methodology for measurement of products and parts on CMM UPMC Zeiss at CMI Brno

Hájková, Alena January 2020 (has links)
This diploma thesis deals with the proposal of internal methodology for measurement of products and parts on CMM UPMC Zeiss at CMI Brno. The first part of this work analyzes the current state of knowledge in the field of accurate measurement on coordinate measuring machines (CMM), which includes the definition of basic metrological concepts, methodology for determining and expressing uncertainties of measurement and a general description of CMM. The diploma thesis also contains a detailed description of the UPMC 850 CARAT S-ACC device from the company Zeiss and summarizes the requirements for the testing laboratory in accordance with the standard ČSN EN 17 025: 2018. The next part of the work is focused on defining and determining the measurement uncertainties for this CMM and on developing a testing procedure for measurements on this machine. The final part of this thesis summarizes the achieved results and recommendations for practice.
15

Stanovení nejistoty měření optického měřicí stroje pomocí laserinterferometru / Determination of measurement uncertainty of the optical measuring machine using a laser interferometer

Fulová, Silvia January 2021 (has links)
This final thesis is dealing with stating uncertainty of optical measuring device Micro-Vu Sol 311, which is located at Faculty of mechanical engineering in Brno. Overview of coordinate measuring machines (CMM for short) and analyzed present status of optical CMM is in summation. This part also includes basic metrology concepts and methodology of determination of uncertainty of measuring instrument. Content of following parts of thesis is detailed description of Micro-Vu SOL 311 machine and etalons that were used in determination of enhanced uncertainty of measurement such as gage blocks, laser interferometer and glass scale. Last part of this thesis includes summary of achieved results and recommendations for practice.
16

Analýza nejistot nepřímých měření / Uncertainties Analyze of Indirect Measurement

Fišr, Petr January 2010 (has links)
This diploma thesis is engaged with problems of expressing measurement uncertainty especially for indirect measurements. This issue is shown here on a few simple examples. Part of this work is a calculation module for the determination of measurement uncertainties, applied to the role of the laboratory 'measurement of the flow orifice.
17

Hydraulický modelový výzkum měrných clon určených pro stanovení průtoku vody v kruhových profilech s volnou hladinou / The hydraulic modelling research of specific shutter intended for determination of water flow in circular profiles with free surface

Heřmanová, Lenka January 2012 (has links)
The main outcome of this Thesis is a set of Q / h characteristic that was obtained extensive hydraulic model research measuring plate designed for the determination of water flow in circular profiles. The final Q / h characteristic are functions of angle and vertical cut remoteness of the top slot from the bottom of the measurement aperture. Part of the output is an overview of the expected values of uncertainties of measurement in practical use in a specific aperture in sewers and evaluation of impacts involved in determining the overall uncertainty of the flow. The performed hydraulic modeling research is therefore possible to determine Q / h and characteristics for circular sections of larger diameter and to determine their uncertainties when using specific plate. For the design and shape measuring plate of the profile with larger average output is part of a supplement for quick design of specific screens.
18

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.
19

Prilog savremenom etaloniranju strujnih mernih transformatora / The Recent Contribution to Calibration of Current Transformers Language of

Naumović Vuković Dragana 29 August 2018 (has links)
<p>U ovoj doktorskoj disertaciji prikazana je koncepcija, realizacija i potvrda nove metode<br />jednovremenog etaloniranja strujnih mernih transformatora sa dve različite merne<br />aparature. Pregledom stručne literature ne postoji podatak da je ova metoda ranije<br />primenjivana. U disertaciji su prikazane različite merne metode za ispitivanje i<br />etaloniranje mernih transformatora koje imaju primenu u savremenoj praksi i koje<br />podrazumevaju i različite merne mogućnosti. Takođe je i ekperimentalno potvrđeno<br />jednovremeno ispitivanje i etaloniranje strujnih mernih transformatora sa nekoliko<br />mernih aparatura koje su zasnovane na različitim metodama. Sprovedna istraživanja i<br />eksperimentalni rezultati pokazuju i potvrđuju niz prednosti ovakvog načina<br />etaloniranja. Detaljna analiza komponenti merne nesigurnosti pokazala je da se<br />primenom ove metode postiže poboljšanje merne nesigurnost etaloniranja za skoro red<br />veličine u odnosu na klasično pojedinačno etaloniranje sa dve različite merne<br />aparature. Analiza uticajnih veličina na mernu nesigurnost pokazuje da se po ovoj novoj<br />metodi etaloniranja eliminiše niz komponenti od kojih su najznačajnije: uticaj<br />nejednakosti referentnih struja i ispitnog opterećenja. Istraživanja su takođe pokazala<br />da jednovremena metoda osim što doprinosi podizanju tačnosti etaloniranja strujnih<br />transformatora, ima primenu i u etaloniranju mernih aparatura za ispitivanje tačnosti<br />mernih transformatora i interkonparaciji strujnih etalon transformatora. Kroz<br />konkretne primere realizovane u praksi, razmotreni su i prikazani načini etaloniranja<br />mernih aparatura za ispitivanje tačnosti ovom novom metodom. Interkomparacijom dva<br />merna sistema visoke klase tačnosti Nacionalnog merološkog instituta Kanade<br />(National Research Council Canada), od kojih je jedna razvijena u Elektrotehničkom<br />Institutu &quot;Nikola Tesla&quot;, pokazana je i prednost primene jednovremene metode u oblasti<br />primarne metrologije strujnih mernih transformatora.</p> / <p>The dissertation presents the concept, its realisation and verification of the new method<br />of simultaneous comparison of the current transformers by two different measuring<br />apparatus. It is shown by searching the literature, that this method has not been used<br />before. In this dissertation different measuring methods for testing and calibration of<br />current transformers, with their different measuring capabilities are presented. Most of<br />them have been used in recent practice. Furthermore, the experimental verification of<br />new simultaneous calibration method is presented. For this reason some measuring<br />apparatus based on different measuring methods were used. Conducted research and<br />experimental results confirmed a number of advantages of this calibration method.<br />Detailed analysis of the components of the uncertainty of measurements shown that<br />using simultaneous method uncertainty of measurements have been improved<br />comparing to method with two individual calibration by different apparatus. In that case<br />some of the measuring uncertainty components can be neglected. The most significant<br />is component caused by variation of referent current and component caused by variation<br />of burden. The research has also showed that simultaneous method can be used for<br />calibration of measuring apparatus for current transformer accuracy testing and their<br />inter-comparisons. The ways of calibration of apparatus for current transformer accuracy<br />testing are considered and presented, through concrete examples realized in practice.<br />A high-accuracy comparison of two NRC (National Research Council Canada)<br />calibration systems were carried out by new simultaneous method. One measuring<br />system is developed at Electrical Engineering institute Nicola Tesla, Belgrade.<br />Accordingly the advantage of simultaneous method applied at the primary metrology of<br />current transformer is verified.</p>
20

Stanovení přesnosti měření v nanometrologii / Determination Accuracy of Measurement in Nanometrology

Šrámek, Jan January 2019 (has links)
The presented doctoral thesis deals with measurements of extremely small sizes in nanometrology using a touch probe, which constitutes a part of a three-coordinate measuring system. It addresses a newly developed method of exact measurements in nanometrology by touch probes. The aim of this work was to expand the measurement options of this device and design a methodology proposal for the measurement of small parts, including the determination of accuracy of measurement of this device when used in nanometrology. The work includes the new methodology for the calculation of uncertainty of measurement, which constitutes a keystone in determining the accuracy of measurement of a accuracy three coordinate measuring system (hereinafter only nano-CMM). The first part of the doctoral thesis analyzes the present situation in the area of evaluation of accuracy of measurement in very accurate length measurements. It defines and describes individual methods implemented in the determination of accuracy of measurement on the instrument nano-CMM. A great emphasis is placed on the methodology of the measurement uncertainty, which draws from the author’s experience as a metrologist working in the laboratories of the Department of Primary nanometrology and technical length, Czech Metrology Institute Brno (hereinafter only CMI Brno). The second part of the doctoral thesis focuses on the determination of accuracy of length measurement in nanometrology, using a large set of measurements that were carried out under the reproducibility and repeatability conditions. There is also described and tested a model procedure utilizing the Monte Carlo method to simulate the measuring system nano-CMM in order to extent the newly created methodology of the measurement of uncertainty using a touch probe on the instrument nano-CMM. A substantial part of this doctoral thesis provides a detailed evaluation of results obtained from experiments that were executed under the repeatability and reproducibility conditions, especially for the purposes of the determination of the uncertainty of measurement. In this doctoral thesis, the uncertainty of measurement is chosen to quantify the accuracy of measurement of the instrument nano-CMM. The final part of this thesis summarizes the knowledge obtained during the scientific research and provides its evaluation. For the methodology used to determine the accuracy of measurement in nanometrology, it also outlines the future development in the area of scientific research, including the practical use in metrological traceability and extremely accurate measurements for customers. Furthermore, it deals with the possible use of other scanning systems compatible with the instrument nano-CMM.

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