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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.
101

Zavedení nových systémů jakosti ve firmě / Introduction of a new Systems of Quality in the Company

Černochová, Veronika January 2014 (has links)
In my graduation these I have been dealing with introducing of a new system of quality in the firm. My these has been divided into two parts. In the first instance I have described academic conception and tools of quality management. In the second part I have been dealing with analyzing the present state in the firm and remedy proposals for improve present situation. At the end of second part I have brought forward economic evaluation.
102

The application of Quality Function Deployment to the design and manufacture of engine main bearings

Foster, John D. 02 February 2010 (has links)
<p>Quality Function Deployment is an extremely useful tool which can be applied within the Systems Engineering Process, to optimize product design and the design process. The use of cross functional teams to analyze customer needs; translate them into design attributes; and subsequently deploy them through every facet of product design, development, and production, can significantly enhance the effectiveness and efficiency of the entire process. Unfortunately the few examples of Quality Function Deployment application, in the academic literature, are generally simplistic and lack any significant depth.</p> <p> The objective of this report is to investigate the application of Quality Function Deployment to a relatively complex product design requirement in an actual manufacturing environment. Specifically, the design and production of engine main bearings at the Federal Mogul plant in Blacksburg, Virginia, are considered.</p> <p> The report examines the use of Quality Function Deployment, as a general design tool; the functional requirements and design constraints of engine main bearings; and the application of one variation of Quality Function Deployment to the evaluation of proposed changes to a bearing's design configuration and the bearing production process.</p> <p> The report concludes with recommendations concerning the implementation of Quality Function Deployment at Federal Mogul, the conduct of Quality Function Deployment instruction at Virginia Tech and a possible avenue for future research.</p> / Master of Science
103

Produktutvecklingsprocess för framtag av en svetsrobotfixtur

Viggesjöö, Daniel January 2022 (has links)
Projektets mål var att ta fram en digital fixtur för en artikel som går från manuell svetsning till robotsvetsning. Produkten skulle analyseras och simuleras för att säkerställa att den även fungerade i praktiken. Målet med rapporten var att ta fram en färdig CAD-fil på en fixtur och bevisa via FEM-analyser och svetsrobotsimulering att den även fungerade i praktiken. Projektet skulle även bidra med en alternativ arbetsmetod för fixturframtagning till Jonsson &amp; Paulsson Industri AB. Produkten skulle också vara ergonomisk utformad. En femstegs-produktutvecklingsprocess användes för att ta fram produkten. Förstudie – Planering – Genomförande – Resultat – Avslut. Genomförandedelen i produktutvecklingsprocessen innehöll två steg, ett konceptgenereringssteg och ett elimineringssteg. Metoder i konceptgenereringssteget innefattar kravspecifikation, funktionsanalys, morfologisk matris, relativ beslutsmatris, FMEA-analys, QFD och prototypbyggnation. Elimineringssteget genomfördes med hjälp av FEM-analyser och svetsrobotsimulationer. Resultatet blev en färdig CAD-fil på svetsrobotfixturen som genomgick och uppfyllde kraven i både kravspecifikationen och utvärderingsmetoderna. Produkten utformades på ett ergonomiskt sätt. Slutsatsen är att produkten fungerar enligt de digitala utvärderingsprocesserna den har genomgått. Mål och syfte är uppfyllt. Detta medför att all den nytta som kommer via automation också uppfylls. / <p>2022-07-01</p>
104

An operations management perspective of knowledge management: towards a knowledge management assessment and improvement tool.

Kapofu, Desmond January 2009 (has links)
This thesis describes the development of a Knowledge Management (KM) Assessment tool for the Operational level of the organisation. Its main focus is to help organisations to identify the KM activities and mechanisms that they could improve in order to improve their operational efficiency. Current KM literature is lacking in guiding organisations in what they need to do in order to implement and formalise KM in their operations with a view to improving operational efficiency. Therefore the aim of this thesis is to fill this gap in the literature and also to influence the manner in which KM is practiced. The research project has three distinct stages: the model development, modification and testing stages. The model development stage synthesises KM literature and a pilot study in order to develop a conceptual model of the KM assessment tool. The second stage of the research project describes the application of the tool in three organisations and details the modifications that were made as a result. Finally, the third stage tests the final version of the KM Assessment tool using four case organisations. The KM Assessment tool presented in this thesis is not a prescriptive KM solution; it emphasises the need to approach KM from a process and task specific perspective. Put another way, KM improvements should be implemented to reflect the processes and task charactaristics of each individual organisation. However, the thesis presents a method of evaluation of such that is unform across organisational types
105

A multi-attribute approach to conceptual system design decisions based on Quality Function Deployment (QFD) and the Analytic Hierarchy Process (AHP)

Powers, Tipmuny C. 07 November 2008 (has links)
This research integrates a multi-attribute decision-support tool, the Analytic Hierarchy Process (AHP), with a customer-focused design methodology, Quality Function Deployment (QFD). The result is a hybrid methodology more complete than either of the two alone, involving synthesis, analysis, and evaluation activities necessary for completing conceptual system design. An indicator was developed for the overall performance of an organization's product and its competitors’ products using the information in a QFD matrix. In addition, a methodology was developed to determine if essential customer requirements and design-dependent parameters (DDPs) have been adequately identified in the QFD matrix. A mathematical relationship was developed which relates technical and competitive assessments in the QFD matrix and helps test for inconsistencies. Finally, an indicator was developed to assess a new product concept for viability in the marketplace and to be used for accomplishing trade-off analyses. Examples are presented throughout this document to further illustrate the concepts. This research is unique in its application. It adds to the body of knowledge for decision-making in the conceptual design phase of the systems engineering process. / Master of Science
106

OMPP para projeto conceitual de aeronaves, baseado em heurísticas evolucionárias e de tomadas de decisões / OMPP for conceptual design of aircraft based on evolutionary heuristics and decision making

Abdalla, Alvaro Martins 30 October 2009 (has links)
Este trabalho consiste no desenvolvimento de uma metodologia de otimização multidisciplinar de projeto conceitual de aeronaves. O conceito de aeronave otimizada tem como base o estudo evolutivo de características das categorias imediatas àquela que se propõe. Como estudo de caso, foi otimizada uma aeronave de treinamento militar que faça a correta transição entre as fases de treinamento básico e avançado. Para o estabelecimento dos parâmetros conceituais esse trabalho integra técnicas de entropia estatística, desdobramento da função de qualidade (QFD), aritmética fuzzy e algoritmo genético (GA) à aplicação de otimização multidisciplinar ponderada de projeto (OMPP) como metodologia de projeto conceitual de aeronaves. Essa metodologia reduz o tempo e o custo de projeto quando comparada com as técnicas tradicionais existentes. / This work is concerned with the development of a methodology for multidisciplinary optimization of the aircraft conceptual design. The aircraft conceptual design optimization was based on the evolutionary simulation of the aircraft characteristics outlined by a QFD/Fuzzy arithmetic approach where the candidates in the Pareto front are selected within categories close to the target proposed. As a test case a military trainer aircraft was designed target to perform the proper transition from basic to advanced training. The methodology for conceptual aircraft design optimization implemented in this work consisted on the integration of techniques such statistical entropy, quality function deployment (QFD), arithmetic fuzzy and genetic algorithm (GA) to the weighted multidisciplinary design optimization (WMDO). This methodology proved to be objective and well balanced when compared with traditional design techniques.
107

Projeto conceitual e análise de desempenho do sistema de admissão de ar em uma aeronave não convencional de combate / Conceptual design and performance analysis of the air intake system in a non-conventional fighter aircraft

Bravo Mosquera, Pedro David 22 May 2017 (has links)
A concepção de aeronaves não convencionais a fim de alcançar um determinado desempenho ou melhoria operacional é sem dúvida um dos objetivos mais importantes da engenheira aeronáutica. Tais melhorias envolvem: redução de arrasto, redução da seção transversal, redução de ruído, redução da distância de decolagem e pouso, aumento da eficiência aerodinâmica, aumento da carga útil, entre outros. Por tanto, métodos de otimização multidisciplinar se tornaram em ferramentas muito úteis para aprimorar o projeto conceitual destas aeronaves. Neste contexto, este trabalho teve como objetivo o desenvolvimento do projeto conceitual de uma aeronave não convencional de combate e a análise de desempenho aerodinâmico do seu sistema de admissão de ar (Intake), tendo como principal característica, estar localizado na parte superior da fuselagem da aeronave (Dorsal Intake). O delineamento conceitual foi desenvolvido através da implementação de metodologias de otimização multidisciplinar de projeto (MDO) na fase de projeto paramétrico, integrando conceitos como: entropia estatística, desdobramento da função qualidade (QFD) e análise de restrições. Além disso, foram usados métodos analíticos e teóricos, ferramentas de desenho assistido por computador (CAD) e simulações da dinâmica dos fluidos computacionais (CFD) para otimizar e obter a configuração final da aeronave. Posteriormente, 5 configurações de asa delta foram selecionadas para avaliar as mudanças de desempenho do dorsal intake sob a influência aerodinâmica das superfícies principais da aeronave (Asa e Fuselagem), em regimes de voo subsônico (Mach = 0.4), transônico (Mach = 0.9) e supersônico (Mach = 1.7; 2) a diversos ângulos de ataque (De &#945; = 10º a &#945; = 30º ). Os resultados encontrados neste trabalho foram avaliados em separado, subsequentemente foram integrados, a fim de obter a nova concepção de aeronave não convencional de combate; a aplicação de MDO permitiu estimar as variáveis de projeto ideais para o desenvolvimento do projeto da aeronave, em relação a sua missão. Em contrapartida, os resultados da integração intake-estrutura mostram que apropriadas características de desempenho e compatibilidade foram mantidas durante as fases de voo subsônicas, para as 5 configurações de asa. No entanto, para velocidades transônicas, a configuração canard apresentou um acréscimo nos níveis de recuperação de pressão total, devido ao fluxo de alta energia na parte superior da fuselagem, o qual é produzido pelo vórtice do canard a moderados ângulos de ataque. Finalmente, para velocidades supersônicas, a asa com dispositivos LEX (Leading Edge Extensions) obteve os melhores níveis de recuperação de pressão total, pois a implementação destes dispositivos apresentou uma montagem mais vantajosa com sua fuselagem para gerar o cone de Mach, aumentando os níveis de recuperação de pressão total e reduzindo a distorção na face do motor. No entanto, para velocidades maiores a Mach = 2, sem importar a configuração de asa, a expansão do escoamento sobre a fuselagem e as asas da aeronave produziu um aumento no número Mach local na entrada do intake, o que reduziu os níveis de desempenho e compatibilidade do mesmo. Em consequência, a posição do intake na parte superior da fuselagem representa uma opção de configuração viável para aeronaves que requerem apenas capacidades de ângulo de ataque razoáveis, tais como aeronaves de caça ar-terra, sendo a asa com dispositivos LEX a geometria que representa melhores qualidades de desempenho na maioria dos 3 regimes de voo avaliados. / The conception of non-conventional aircraft with the aim of achieving a certain performance or operational improvement is undoubtedly, one of the most important objectives of the aeronautical engineering. These improvements involve: drag reduction, cross section reduction, noise reduction, shortening of take-off and landing distance, increase of aerodynamic efficiency, payload increase, among others. Therefore, optimization multidisciplinary methods became in very important tools to upgrade the conceptual design phase of these aircraft. In this context, this work had as aim the development of the conceptual design of a nonconventional fighter aircraft and the aerodynamic performance analysis of its air intake, having as main characteristic to be located at the top of the fuselage (Dorsal Intake). The conceptual design was developed through the implementation of multidisciplinary design optimization (MDO) methods in the parametric design phase, integrating concepts of: statistical entropy, quality function deployment (QFD) and constraint analysis. Besides that, it was used analytical and theoretical methods, computer-aided design (CAD) tools and computational fluid dynamics (CFD) simulations to optimize and obtain the final aircraft configuration. Subsequently, 5 delta wing configurations were selected to evaluate the dorsal intake performance changes under the aerodynamic influence of the main aircraft surfaces (Wings and Fuselage) in subsonic (Mach = 0.4), transonic (Mach = 0.9) and supersonic (Mach = 1.7; 2) flight regimes, at various angles of attack (From &#945; = 10º to &#945; = 30º ). The results found in this work were evaluated separately, later these were integrated, in order to get the new conception of non-conventional fighter aircraft; the MDO application allowed to estimate the ideal design variables for developing the aircraft design, regarding to its mission. On the other hand, the results of the intake-structure integration shown that appropriate performance and compatibility characteristics were maintained during the subsonic flight stages for the 5 wing configurations. However, for transonic velocities, the canard configuration presented an increase in the total pressure recovery levels, due to the high energy flux on the fuselage, which is produced by the canard vortex at moderate angles of attack. Finally, for supersonic velocities, the wing with LEX (Leading Edge Extensions) devices got the best levels of total pressure recovery, because the implementation of these devices presented a more advantageous assembly with its fuselage to generate the Mach cone, increasing the total pressure recovery levels and reducing the distortion at the engine face. However, for velocities higher than Mach = 2, regardless the wing configuration, the flow expansion on the fuselage and the wings produced an increase in the local Mach number in the intake entrance, which reduced the performance and compatibility levels of it. As a consequence, the top mounted intake position represents an option of viable configuration to aircraft that require only reasonable angles of attack capabilities, such as air-to-ground fighter aircraft, being the wing with LEX devices the geometry that represents better performance qualities in the majority of the 3 evaluated flight regimes.
108

OMPP para projeto conceitual de aeronaves, baseado em heurísticas evolucionárias e de tomadas de decisões / OMPP for conceptual design of aircraft based on evolutionary heuristics and decision making

Alvaro Martins Abdalla 30 October 2009 (has links)
Este trabalho consiste no desenvolvimento de uma metodologia de otimização multidisciplinar de projeto conceitual de aeronaves. O conceito de aeronave otimizada tem como base o estudo evolutivo de características das categorias imediatas àquela que se propõe. Como estudo de caso, foi otimizada uma aeronave de treinamento militar que faça a correta transição entre as fases de treinamento básico e avançado. Para o estabelecimento dos parâmetros conceituais esse trabalho integra técnicas de entropia estatística, desdobramento da função de qualidade (QFD), aritmética fuzzy e algoritmo genético (GA) à aplicação de otimização multidisciplinar ponderada de projeto (OMPP) como metodologia de projeto conceitual de aeronaves. Essa metodologia reduz o tempo e o custo de projeto quando comparada com as técnicas tradicionais existentes. / This work is concerned with the development of a methodology for multidisciplinary optimization of the aircraft conceptual design. The aircraft conceptual design optimization was based on the evolutionary simulation of the aircraft characteristics outlined by a QFD/Fuzzy arithmetic approach where the candidates in the Pareto front are selected within categories close to the target proposed. As a test case a military trainer aircraft was designed target to perform the proper transition from basic to advanced training. The methodology for conceptual aircraft design optimization implemented in this work consisted on the integration of techniques such statistical entropy, quality function deployment (QFD), arithmetic fuzzy and genetic algorithm (GA) to the weighted multidisciplinary design optimization (WMDO). This methodology proved to be objective and well balanced when compared with traditional design techniques.
109

Projeto conceitual e análise de desempenho do sistema de admissão de ar em uma aeronave não convencional de combate / Conceptual design and performance analysis of the air intake system in a non-conventional fighter aircraft

Pedro David Bravo Mosquera 22 May 2017 (has links)
A concepção de aeronaves não convencionais a fim de alcançar um determinado desempenho ou melhoria operacional é sem dúvida um dos objetivos mais importantes da engenheira aeronáutica. Tais melhorias envolvem: redução de arrasto, redução da seção transversal, redução de ruído, redução da distância de decolagem e pouso, aumento da eficiência aerodinâmica, aumento da carga útil, entre outros. Por tanto, métodos de otimização multidisciplinar se tornaram em ferramentas muito úteis para aprimorar o projeto conceitual destas aeronaves. Neste contexto, este trabalho teve como objetivo o desenvolvimento do projeto conceitual de uma aeronave não convencional de combate e a análise de desempenho aerodinâmico do seu sistema de admissão de ar (Intake), tendo como principal característica, estar localizado na parte superior da fuselagem da aeronave (Dorsal Intake). O delineamento conceitual foi desenvolvido através da implementação de metodologias de otimização multidisciplinar de projeto (MDO) na fase de projeto paramétrico, integrando conceitos como: entropia estatística, desdobramento da função qualidade (QFD) e análise de restrições. Além disso, foram usados métodos analíticos e teóricos, ferramentas de desenho assistido por computador (CAD) e simulações da dinâmica dos fluidos computacionais (CFD) para otimizar e obter a configuração final da aeronave. Posteriormente, 5 configurações de asa delta foram selecionadas para avaliar as mudanças de desempenho do dorsal intake sob a influência aerodinâmica das superfícies principais da aeronave (Asa e Fuselagem), em regimes de voo subsônico (Mach = 0.4), transônico (Mach = 0.9) e supersônico (Mach = 1.7; 2) a diversos ângulos de ataque (De &#945; = 10º a &#945; = 30º ). Os resultados encontrados neste trabalho foram avaliados em separado, subsequentemente foram integrados, a fim de obter a nova concepção de aeronave não convencional de combate; a aplicação de MDO permitiu estimar as variáveis de projeto ideais para o desenvolvimento do projeto da aeronave, em relação a sua missão. Em contrapartida, os resultados da integração intake-estrutura mostram que apropriadas características de desempenho e compatibilidade foram mantidas durante as fases de voo subsônicas, para as 5 configurações de asa. No entanto, para velocidades transônicas, a configuração canard apresentou um acréscimo nos níveis de recuperação de pressão total, devido ao fluxo de alta energia na parte superior da fuselagem, o qual é produzido pelo vórtice do canard a moderados ângulos de ataque. Finalmente, para velocidades supersônicas, a asa com dispositivos LEX (Leading Edge Extensions) obteve os melhores níveis de recuperação de pressão total, pois a implementação destes dispositivos apresentou uma montagem mais vantajosa com sua fuselagem para gerar o cone de Mach, aumentando os níveis de recuperação de pressão total e reduzindo a distorção na face do motor. No entanto, para velocidades maiores a Mach = 2, sem importar a configuração de asa, a expansão do escoamento sobre a fuselagem e as asas da aeronave produziu um aumento no número Mach local na entrada do intake, o que reduziu os níveis de desempenho e compatibilidade do mesmo. Em consequência, a posição do intake na parte superior da fuselagem representa uma opção de configuração viável para aeronaves que requerem apenas capacidades de ângulo de ataque razoáveis, tais como aeronaves de caça ar-terra, sendo a asa com dispositivos LEX a geometria que representa melhores qualidades de desempenho na maioria dos 3 regimes de voo avaliados. / The conception of non-conventional aircraft with the aim of achieving a certain performance or operational improvement is undoubtedly, one of the most important objectives of the aeronautical engineering. These improvements involve: drag reduction, cross section reduction, noise reduction, shortening of take-off and landing distance, increase of aerodynamic efficiency, payload increase, among others. Therefore, optimization multidisciplinary methods became in very important tools to upgrade the conceptual design phase of these aircraft. In this context, this work had as aim the development of the conceptual design of a nonconventional fighter aircraft and the aerodynamic performance analysis of its air intake, having as main characteristic to be located at the top of the fuselage (Dorsal Intake). The conceptual design was developed through the implementation of multidisciplinary design optimization (MDO) methods in the parametric design phase, integrating concepts of: statistical entropy, quality function deployment (QFD) and constraint analysis. Besides that, it was used analytical and theoretical methods, computer-aided design (CAD) tools and computational fluid dynamics (CFD) simulations to optimize and obtain the final aircraft configuration. Subsequently, 5 delta wing configurations were selected to evaluate the dorsal intake performance changes under the aerodynamic influence of the main aircraft surfaces (Wings and Fuselage) in subsonic (Mach = 0.4), transonic (Mach = 0.9) and supersonic (Mach = 1.7; 2) flight regimes, at various angles of attack (From &#945; = 10º to &#945; = 30º ). The results found in this work were evaluated separately, later these were integrated, in order to get the new conception of non-conventional fighter aircraft; the MDO application allowed to estimate the ideal design variables for developing the aircraft design, regarding to its mission. On the other hand, the results of the intake-structure integration shown that appropriate performance and compatibility characteristics were maintained during the subsonic flight stages for the 5 wing configurations. However, for transonic velocities, the canard configuration presented an increase in the total pressure recovery levels, due to the high energy flux on the fuselage, which is produced by the canard vortex at moderate angles of attack. Finally, for supersonic velocities, the wing with LEX (Leading Edge Extensions) devices got the best levels of total pressure recovery, because the implementation of these devices presented a more advantageous assembly with its fuselage to generate the Mach cone, increasing the total pressure recovery levels and reducing the distortion at the engine face. However, for velocities higher than Mach = 2, regardless the wing configuration, the flow expansion on the fuselage and the wings produced an increase in the local Mach number in the intake entrance, which reduced the performance and compatibility levels of it. As a consequence, the top mounted intake position represents an option of viable configuration to aircraft that require only reasonable angles of attack capabilities, such as air-to-ground fighter aircraft, being the wing with LEX devices the geometry that represents better performance qualities in the majority of the 3 evaluated flight regimes.
110

För ett effektivt operatörsunderhåll / For efficient operator maintenance

El Khabiry, Mohamed January 2021 (has links)
Detta examensarbete är utfört på Astrazeneca Södertälje inom Meto-försteg som är en del av fabriken API, med syftet att effektivisera underhållsarbetet. En kartläggning av det förebyggande underhållet genomfördes, i syfte att identifiera underhållsarbete som utförs dubbelt av både operatörer inom API och underhållsleverantören Caverion. Examensarbetet presenterar en redogörelse för begrepp inom underhåll, TPM (Total Productive Maintenance) och beslutsmodellen QFD (Quality Function Deployment) vilka utgör den teoretiska utgångspunkten för resultat och analys. Examensarbetet bygger på insamlade observationer och intervjumaterial från personal verksamma inom drift och underhåll. Studiens resultat visar att det genomförs överlappningar i underhållsarbetet, exempelvis inom veckotillsyn och förebyggande underhåll (FU) inom fabriksdelen Meto- försteg. Både operatörer och Caverion genomför underhållsåtgärder som innefattar visuell kontroll av oljenivåer, läckage, missljud, vibrationer för ett antal maskiner. En tydligare fördelning av underhållsåtgärder mellan operatörer och Caverion kommer bidra till effektiviseringen av underhållsarbetet. / This thesis was carried out at Astrazeneca Södertälje within Meto-pre stage, which is part of the factory API, intending to streamline the maintenance work. Apreventive maintenance survey was carried out, to identify maintenance work that was performed twice by both API operators and the maintenance provider Caverion. The thesis presents an account of concepts in maintenance, TPM (Total Productive Maintenance), and the decision model QFD (Quality Function Deployment) which constitute the theoretical starting point for results and analysis. The thesis is based on collected observations and interview materials from staff active in operations and maintenance. The results of the study show that there are overlaps in maintenance work, for example in weekly supervision/inspections and preventive maintenance (FU) within the factory part Meto-pre stage. Both operators and Caverion carry out maintenance operations that include a visual control of oil levels, leakage, noise, vibrations for several machines. A clearer distribution of maintenance measures between operators and Caverion will contribute to the streamlining of maintenance work.

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