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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.
1

New waviness measurement system using RGB LED lights

Biba, Panagiota January 2015 (has links)
Due to the rapid technological developments in the car industry and the high quality demands of customers, manufacturers and researchers focus on the reduction of surface roughness making use of various surface topography measurement systems. This master thesis focuses on development of a waviness measurement system (WMS) at Volvo Cars where light from different heights and angles illuminates the surface of an extended object in order to acquire images with different intensities due to shadowing effect and reflection. With this, surface irregularities and imperfections can be detected both in polished and unpolished surfaces for improving the car panels in the manufacturing process.  The initial WMS idea was to illuminate the surface at different heights from the four corners of a dark room using 20 flash lights and a camera positioned exactly on the top of the surface in the middle of the room. The first light goes on and the image is acquired. This procedure continues for all flash lights in 19s.The acquired images were evaluated by Matlab application. With the new WMS system flash lights are replaced by 32 RGB COB LED lights using the DMX512 protocol to communicate with them. The system runs in 9s which is half the time of the old WMS system. New LabView and Matlab codes were adjusted to the new parameters and devices. In the end, measurements were taken with different surfaces, exposure times and color lights. Details of the new devices and software are analyzed in this thesis.
2

Large Signal RF Measurement Systems and Implementation of a Tuned Receiver System

Azhar, Ahsan January 2008 (has links)
<p><p>This report shows a survey of sate of the art different large signal RF measurement systems. Such measurement systems are discussed in detail with respect to their architecture, method of measurement, calibration, accuracy, dynamic range and bandwidth. Finally, a RF measurement system for large signal was designed and implemented. This measurement system was based on a tuned receiver. Harmonic distortion type measurements were taken by this system and time domain waveforms were reconstructed using external software.</p></p>
3

Large Signal RF Measurement Systems and Implementation of a Tuned Receiver System

Azhar, Ahsan January 2008 (has links)
This report shows a survey of sate of the art different large signal RF measurement systems. Such measurement systems are discussed in detail with respect to their architecture, method of measurement, calibration, accuracy, dynamic range and bandwidth. Finally, a RF measurement system for large signal was designed and implemented. This measurement system was based on a tuned receiver. Harmonic distortion type measurements were taken by this system and time domain waveforms were reconstructed using external software.
4

Mätsystemanalys för kontrollmätning av stiftshåldiameter på en borrkrona

Gallego, Julio January 2016 (has links)
Detta examensarbete har utförts på Sandvik Mining and Construction Tools AB (SMC) och hade som uppdrag att införa arbete med statistisk processtyrning (SPS) vid en produktionscell. Innan implementering av SPS tekniker krävs det en säkerställning av mätsystemets tillförlitlighet. Målet med arbetet är att genom en mätsystemanalys (MSA) utvärdera den befintliga mätmetodens duglighet och erbjuda berörd personal vid SMC en ny mätmetodsmodell om den befintliga mätmetoden fallerar. Metoden som användes för att utföra MSA var en fallstudie. Analysen genomfördes med hjälp av olika förbättringsarbetssätt inom Sex sigmas metodik som till exempel DMAIC-förbättringscykel och fiskbensdiagram. Underlagen för studien baserades på kvantitativa- och kvalitativa data. Insamling av kvantitativa data utfördes med hjälp av strukturerade observationer medan kvalitativa data samlades in med hjälp av en nulägesanalys, individuella intervjuer, benchmarking och litteraturstudie. Arbetet består av 3 analyser utförda på två olika mätsystem. Resultatet pekade på att de befintliga mätsystemen inte var tillförlitliga nog för att kunna användas i produktionen hos SMC. Mätsystem 1 (mätmaskinen) exkluderades från vidare analyser på grund av tidsbrist för att kunna genomföra förbättringar på det. Mätsystem 2 gick igenom en förbättringsfas där flera grundorsaker till variationer i processen analyserades och förbättrades. Dessvärre blev mätsystemet fortfarande odugligt för att användning i produktionen. Med hjälp av matematiska och statistiska beräkningar fastställdes det att mätmaskinen är det lämpligaste mätsystem att använda inom produktionen hos SMC. Det kan betyda att mätsystemets acceptans är beroende av mätinstrumentet. / This essay has been carried out at Sandvik Mining and Construction Tools AB (SMC). The purpose of study was to introduce the statistical process control methodology (SPC) at the actual production cell. Before the implementation of SPC-techniques, it is required an analysis to ensure the measurement systems reliability. The objective of the work is that through a measurement system analysis (MSA) evaluate the existing measurement method capability and provide the relevant personnel at SMC with a new measurement model if the existing measurements methods fails.   The method used to perform the MSA was a case study. The analysis was performed using various improvement works within Six-Sigma methods such as DMAIC improvement cycle and fishbone diagram. The study was based on quantitative and qualitative data. Collection of quantitative data was performed using structured observations while qualitative data was assembled by means of a situation analysis, individual interviews, benchmarking and a literature review. The work consists of three studies performed on two different measurement systems.   The results indicated that the existing measurement systems were not reliable enough to be used in the SMC production. Measuring system 1 (measuring machine) were excluded from further analysis because of insufficient time to carry out improvements on it. Measuring system 2 went through a development phase where several causes of variations in the process were analyzed and improved. Unfortunately, the measurement system was still unfit for use in production.   With the help of mathematical and statistics calculations, it was determined that the measuring machine is the most appropriate measurement system to use in the SMC production process. This could mean that the measurement system acceptance is dependent on the measuring instrument
5

Universal Experimental Measurement System «Sun-Walker» : Automotive measurement system for the evaluation of the solar irradiation distribution for the tests of the solar concentrated systems.

Gaynullin, Bakhram January 2010 (has links)
This Thesis project is a part of the research conducted in Solar industry. ABSOLICON Solar Concentrator AB has invented and started production of the prospective solar concentrated system Absolicon X10. The aims of this Thesis project are designing, assembling, calibrating and putting in operation the automatic measurement system intended to evaluate distribution of density of solar radiation in the focal line of the concentrated parabolic reflectors and to measure radiation from the artificial source of light being a calibration-testing tool.On the basis of the requirements of the company’s administration and needs of designing the concentrated reflectors the operation conditions for the Sun-Walker were formulated. As the first step, the complex design of the whole system was made and division on the parts was specified. After the preliminary conducted simulation of the functions and operation conditions of the all parts were formulated.As the next steps, the detailed design of all the parts was made. Most components were ordered from respective companies. Some of the mechanical components were made in the workshop of the company. All parts of the Sun-Walker were assembled and tested. The software part, which controls the Sun-Walker work and conducts measurements of solar irradiation, was created on the LabVIEW basis. To tune and test the software part, the special simulator was designed and assembled.When all parts were assembled in the complete system, the Sun-Walker was tested, calibrated and tuned.
6

The Post-Weld-Shift Measurement of Butterfly-Type Laser Module Packaging by Capacitance Displacememt System

Hu, Feng-ruei 24 July 2007 (has links)
A novel technique by employing a capacitance displacement measurement system to measure the post-weld-shift (PWS) caused by laser welding in the butterfly-type laser diode module packaging process is proposed. Reduction of the PWS is an important issue in developing low-cost and high-performance semiconductor laser module. Prior to the reduction and compensation of the PWS, a measurement system of PWS must be constructed. In comparison to the high-magnification camera with image capturing system (HMCICS) limited in resolution of 0.07£gm due to its pixels, a measurement system with a higher resolution of 0.0254£gm is used. During the measurement procedure, the PWS of the ferrule probed by the sensors is converted into the fiber misalignment shifts. The coupling efficiency can be improved over 70% after compensation. The result indicates that the PWS can be qualitatively measured and quantitatively computed.
7

Measurement system for laboratory use : For studies in electrical science

Lindström, Jonas January 2015 (has links)
The purpose of this project is to create a measurement system aimed for a laboratory environment at Uppsala University. The measurement system will be used by students for laboratories of electrical science. It will include a measurement station and an application that will be used by the students.  A specification of 16 channels of measuring data, 8 current and 8 voltage, was given by the client. Beside this specification there were 8 others to fulfil. The measurement station is connected to a compactRIO which will enable the possibility to graphically and numerically represent the results through an application created in Labview. The application will include time and phasor representations of both current and voltage. It will also include two power vectors for 6 channels each. The result of this project is a fully working measurement system which generates a good overview of measurements made on an electrical power system. All given specifications was fulfilled except one, which was not possible to achieve with the chosen methodology.
8

Automatizovaný měřicí testovací systém / Automation Measurement System

Zálešák, Marek January 2010 (has links)
The follow text describes National Instruments Company's program LabVIEW and bus GPIB. The main part of the text solves the motion and description of software, which was created by help of LabWIEV program for Automation Measurement System. In conclusion of this work are the demonstration and results of control measurements, which were generated by this measuring system.
9

Measurement System Analysis : For Battery Production Using DMAIC at Northvolt AB

Nguyen, Phuc, Sahlberg, Adam January 2020 (has links)
As battery manufacturing is enclosed with multiple quality and safety requirements, the batteryindustry needs adequate Measurement Systems (MS) to provide high product quality and ensure a safe working environment. The study purpose was to improve the performance of an MS for battery production by utilizing MSA and Six Sigma methodology, and to make appropriate recommendations for improvement and future control. The study included 28 measurement instruments which were evaluated by the utilization of a framework consisting of five different errors identified in the literature, namely bias, linearity, stability, reproducibility and repeatability. This framework is considered as the theoretical contribution of this study. The improvement methodology DMAIC (Define-Measure-Analyze-Improve-Control) was used to perform the case study. The results indicate an overall improved MS and generated improvement suggestions of three recurrent scenarios that arose in the analysis. Moreover, a company adopted control plan with an intention to serve as a basis for future work within MSA is presented and concerns the practical contribution of this work. The results provide helpful support as well as establish a foundation of how to maintain a well-performing MS for Northvolt. By implementing the suggested recommendations, the potential saving was estimated to 395 000 SEK annually. / En mätsystemanalys genomfördes hos batteritillverkaren Northvolt. Då batteriproduktionomgärdas av flera kvalitets- och säkerhetskrav behöver batteriindustrin tillförlitliga mätsystem för att generera hög produktkvalitet samt upprätthålla en säkerhet för användare. Studien syftade till att förbättra prestandan hos ett mätsystem inom batteriproduktion genom användandet av mätsystemanalys och Sex Sigma-metodik, samt att ge lämpliga rekommendationer för förbättringar och framtida kontroll. Studien inkluderade 28 mätinstrument som utvärderades genom användningen av ett ramverk bestående av fem olika mätsystemfel identifierade i litteraturen, nämligen bias, linearity, stability, reproducibility och repeatability. Detta ramverk betraktas som det teoretiska bidraget från denna studie. Förbättringmetodiken DMAIC (Define-Measure-Analyze-Improve-Control) användes för att utföra fallstudien. Resultaten visar på ett övergripande förbättrat mätsystem och genererade förbättringsförslag på tre återkommande scenarier som uppstod i analysen. Dessutom presenteras en företagsanpassad kontrollplan med avsikt att utgöra en grund för framtida arbete inom mätsystemanalys och ses det praktiska bidraget från denna studie. Resultaten förblir ett användbartstöd samt skapar en grund för hur Northvolt upprätthåller ett högpresterande mätsystem. Genom att säkerställa prestandan av mätsystemet uppskattades den potentiella besparingen till 395 000 SEK årligen.
10

Pesquisa-ação sobre as formas de promover um aumento na participação dos funcionários no desenvolvimento e uso do sistema de medição de desempenho de uma empresa de bens de capital

Leal, João Batista Sobreira 26 February 2009 (has links)
Made available in DSpace on 2016-06-02T19:51:39Z (GMT). No. of bitstreams: 1 2527.pdf: 2598997 bytes, checksum: 9f4e8a6113e894b9bf182eeaee49c181 (MD5) Previous issue date: 2009-02-26 / The purpose of this essay is to investigate ways to promote an increase at the participation of employees in the development and use of the performance measurement system in an industrial goods manufacturer. Along with economical globalization, several performance measurement models begin to appear and companies in general are brought to invest in the search for the model that better fits each one s purpose. The effort is focused in the development, implementation and use of performance measurement systems. Among a number of proposed models, the one that gained more recognition worldwide was BSC. This fact itself does not guarantee the full use of the performance measurement system. Employee s participation and commitment has been an issue that deserves attention from researchers because it is an unquestionable fact that its involvement increases the performance of the individual and improves the motivation of the group. For this research it was chosen the action-research method, due to the fact of it to allow researchers to play an active role in the very reality of observed facts. The research had the support of large bibliographic studies to identify and evaluate influent factors to development and evolution of SMD. During action-research work, questionnaires were applied, interviews were conducted and thoughts were made about the adopted actions and results achieved. As a final result of field research, a better understanding of process change, skill development in the use of SMD, system management and involvement of stakeholders were achieved. Recommendations resultant of this research included managers, quality management staff and executives of the company, the development of employees, the improvement of SMD use, ownership and continuous improvement of the business. / O objetivo precípuo desta dissertação é buscar formas para aumentar a participação dos funcionários no desenvolvimento e uso do sistema de medição de desempenho em uma empresa de bens de capital. Juntamente com a globalização da economia, a partir dos anos oitenta, começaram a surgir diversos modelos e propostas de sistemas de medição de desempenho, os quais têm levado as empresas a investir na busca do modelo que melhor sirva ao propósito de cada qual. O esforço se concentra no campo do desenvolvimento, implementação e uso de sistema de medição de desempenho. Dentre os vários modelos propostos o que mais se destacou em todo o mundo foi o BSC. Este fato, per se, não garante a plenitude de utilização do sistema de medição de desempenho. O envolvimento e a participação dos funcionários é assunto que tem merecido a atenção dos pesquisadores porque é fato incontestável que seu envolvimento aumenta o desempenho do indivíduo e auxilia a motivação do grupo. Para esta pesquisa optou-se pela pesquisa-ação pelo fato de ela permitir, ao pesquisador, desempenhar um papel ativo na própria realidade dos fatos observados. O desenvolvimento desta investigação foi alicerçado em ampla revisão bibliográfica para identificar e avaliar fatores que influenciam o desenvolvimento e evolução do SMD. Para levar a bom termo o desenvolvimento da pesquisa-ação, no decorrer do trabalho foram aplicados questionários, conduzidas entrevistas e feitas reflexões sobre as ações tomadas e os resultados obtidos. Como resultado final da pesquisa de campo, foi obtido um melhor entendimento do processo de mudança, do desenvolvimento de habilidade no uso do SMD, de gestão do sistema e envolvimento dos stakeholders. As sugestões resultantes deste trabalho de pesquisa abrangeu os gerentes, o pessoal da gestão da qualidade e a alta direção da empresa, o desenvolvimento dos funcionários, a melhorias da gestão do SMD, propriedade (ownership) e melhoria contínua do desempenho do negócio.

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