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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

Geometrical and dimensional Measurement Planning : - a systematic and holistic approach

Lindqvist, Richard January 2011 (has links)
För att försäkra sig om den slutliga kvaliteten på maskinbearbetade komponenter måste tillverkande företag mäta och verifiera de geometriska och dimensionella egenskaperna på komponenter innan dem skickas vidare nedströms till den mer värdeskapande monteringen. Det är idag vanligt att den geometriska och dimensionella mätningen och verifieringen uppstår varje gång då en maskin ställs om, när man startar om eller startar upp en ny produktionslina eller då en produktionsprocess ändras. Produktionsteknisk mätteknik och resultat från utförda mätningar används sedan som indata för statistisk processtyrning och övervakning av produktionsprocesser. Syftet med vår forskning har varit att först ta fram en nulägesbild av mätteknisk beredning inom fordons- och flygindustrin och utifrån den identifiera framtida trender med behovsanalys och gap. Utifrån analysen har vi sedan utforskat och utvecklat en modell och metodik för mätteknisk mät- och styrbarhetsberedning. I denna licentiat avhandling har vi utforskat området geometrisk och dimensionell mät- och styrbarhetsberedning (GMCP - Geometrical and dimensional Measurement and Controllability Planning). Vi presenterar en nulägesanalys av området och vi presenterar en teori med modell och ramverk för GMCP. Vidare har vi utforskat en metodik och verktyg benämnd kvalitetssäkringsmatris (QAM - Quality Assurance Matrix) och som vi lyfter fram i denna avhandling. I slutet av avhandlingen presenteras och diskuteras dem hittills uppnådda resultaten från forskningen och i det sista kapitlet dras slutsatser och den fortsatta forskningen inom ”SIMET-GICP” projektet presenteras. / In order to ensure final product quality on machined components, manufacturing enterprises must measure and inspect the geometrical and dimensional characteristics of components before they go into higher-value assemblies. Commonly, the geometrical and dimensional measurement and inspection occurs every time at machine tool set-up, when a line is restarted or if the production process is changed. Production metrology and results from production measurements is used as input data for statistical process control and monitoring of production processes. The purpose of our research has been to firstly perform a state of the art analysis in the area of measurement planning applied in the automotive and aerospace industry. The output from the state of the art study has then been used to identify future trends and needs including a gap analysis. Then we used the analysis to explore and develop a model and methodology for measurement and controllability planning.   In this licentiate thesis we have explored the area of GMCP (Geometrical and dimensional Measurement and Controllability Planning). As a major result in this thesis a state of the art survey on GMCP is presented. Based on the state of the art study a theory and model framework for GMCP has been explored and a methodology and tool called QAM (Quality Assurance Matrix) is highlighted in this thesis. In the end of the thesis we present and discuss the present research results we have accomplished and in the final chapter we draw conclusions and outline the continued research within the SIMET-GICP project. / QC 20111027 / SIMET 1
2

Metodologia para estimação de estados e alocação de equipamentos de medição em sistemas de distribuição de energia elétrica / Methodology for state estimation and allocation of measurement equipment in electricity distribution system

Duque, Felipe Gomes 12 April 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-07-19T15:32:30Z No. of bitstreams: 1 felipegomesduque.pdf: 3507645 bytes, checksum: d7e6e84ea872f86ac2bd64caa361fce0 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-07-23T15:26:16Z (GMT) No. of bitstreams: 1 felipegomesduque.pdf: 3507645 bytes, checksum: d7e6e84ea872f86ac2bd64caa361fce0 (MD5) / Made available in DSpace on 2018-07-23T15:26:16Z (GMT). No. of bitstreams: 1 felipegomesduque.pdf: 3507645 bytes, checksum: d7e6e84ea872f86ac2bd64caa361fce0 (MD5) Previous issue date: 2018-04-12 / O presente trabalho propõe uma metodologia de planejamento de medição em Sistemas de Distribuição de Energia Elétrica (SDE) e um novo método para estimação de estados destes sistemas. Para tanto, a técnica metaheurística de otimização bio-inspirada denominada Modified Monkey Search (MMS) é proposta para alocação ótima de medidores inteligentes e unidades de medição fasorial. O modelo de otimização é multiobjetivo e visa a maximização da eficácia do processo de estimação de estados com o custo mínimo de investimento em sistemas de medição. O método de Pareto é associado ao algoritmo MMS para o tratamento adequado destes objetivos conflitantes considerando-se custos reais associados aos equipamentos de medição. Adicionalmente, um novo método de estimação de estados baseado na modelagem de um Fluxo de Potência Ótimo (FPO) modificado é proposto, cuja resolução é dada pelo Método de Pontos Interiores (MPI). O algoritmo MMS determina as variáveis discretas associadas aos tipos de equipamentos de medição, bem como aos locais de instalação dos mesmos no SDE. Estudos são realizados para comparar a nova metodologia de estimação de estados proposta com uma metodologia tradicional, bem como para comparar os resultados da metaheurística de otimização aplicada ao problema com outras técnicas desenvolvidas para esta finalidade. Os estudos são conduzidos com sistemas da literatura, além de um sistema real de médio porte de uma concessionária brasileira. / The present work proposes an approach for planning the measurement locations in Electric Distribution Systems (EDS) and a new method for static state estimation. The bio-inspired meta-heuristic optimization technique called Modified Monkey Search (MMS) is proposed for optimal allocation of smart meters and phasor measurement units. The optimization model is multiobjective and aims at maximizing the efficiency of the state estimation process with minimum measurement investment costs. The Pareto’s method is associated with the MMS algorithm for handling the conflicting objectives in a suitable manner by considering real costs related to measurement equipments. In addition, a new method for static state estimation based on the modeling of a modified Optimal Power Flow (OPF) is proposed, whose solution is given by the Interior Point Method (IPM). The MMS algorithm determines the discrete variables related to types and location of measurement equipments in the system. Studies are made to compare the new approach for static state estimation with a traditional method, as well as to compare the results from the meta-heuristic optimization applied to the problem with existing techniques. The studies are performed using systems from the literature, as will as a practical medium size distribution network from a Brazilian utility.

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