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Ecodesign utilizando QFD, métodos Taguchi e DFEPrates, Gláucia Aparecida January 1998 (has links)
Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. / Made available in DSpace on 2012-10-17T06:16:53Z (GMT). No. of bitstreams: 0
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Influência do defeito tipo cunha no comportamento mecânico de juntas de liga de alumínio 2198 soldadas por fricção por ponto (FSpW) / Influence of hook defect on mechanical behavior of AA2198 friction spot weldsBarros, Pablo Aronne Funchal de 01 February 2015 (has links)
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Previous issue date: 2015-02-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / One of the main considerations in selecting materials to manufacture
aircraft structures is related to weight saving [1]. In this context, the promising
aluminum-lithium alloys have been receiving special attention in aerospace
applications due to its attractive combination of low density, high specific
strength and corrosion resistance [2-5]. Due to difficulties joining these alloys by
conventional welding processes associated to their high thermal conductivity
and low melting temperature, solid-state joining technologies emerge as great
possibilities to simultaneously solve problems of solidification defects and
increasing weight. The feasibility of Friction Spot Welding (FSpW) in joining
sheets of lightweight material (e.g. aluminum alloys) places this technology as a
potential replacement to the spot-like joint processes, as resistance spot
welding (RSW) and laser spot welding (LSW), for application in automotive and
aerospace industries [6-8]. In this work, the influence of hook defect on the lap
shear strength (LSS) of AA2198-T8 friction spot welds was studied. The effects
of process parameters was evaluated in terms of LSS and related to the
microstructural configurations. The values of hook length measurements and
the LSS were used as response in optimization process developed using the
statistical tool of DoE technique with Taguchi Method. Finally it was possible to
compare the hook behavior with lap shear strength results. The higher influence
on the weld performance was exerted by plunge depth whereas rotational
speed was found to be a less significant parameter. Through the minimization of
the hook defect, a beneficial response on the weld performance was observed,
which was associated to the absence of a potential site for crack nucleation. In
spite of inherent discontinuities, promising results were found for aluminum
joints for aerospace applications. / Uma das principais considerações na seleção de materiais para a
fabricação de estruturas de aeronaves está relacionada à redução de peso [1].
Neste contexto, ligas de alumínio-lítio têm se destacado em aplicações
aeroespaciais devido à sua atraente combinação de propriedades como baixa
densidade, alta resistência específica e resistência à corrosão [2-5]. Devido às
dificuldades para união destas ligas por processos convencionais de soldagem
associadas às altas condutividades térmicas e baixas temperaturas de fusão,
tecnologias de soldagem no estado sólido emergem com grande potencial para
simultaneamente reduzir os defeitos de solidificação e aumento de peso. A
viabilidade da Soldagem por Fricção por Ponto (do inglês – Friction Spot
Welding – FSpW) para unir chapas de materiais leves posiciona esta tecnologia
como potencial substituta para os processos de união por ponto, como
soldagem por resistência (RSW) e soldagem a laser (LSW), para aplicação nas
indústrias automotiva e aeroespacial [6-8]. O presente trabalho visou estudar a
influência do defeito de cunha na resistência ao cisalhamento (RC) das juntas
da liga de alumínio 2198-T8 fabricadas por FSpW. O efeito dos parâmetros de
processo foi avaliado em relação à RC e relacionado com as configurações
microestruturais. Os valores de comprimento de cunha e RC foram utilizados
como resposta no processo de otimização desenvolvido utilizando-se a
ferramenta estatística de planejamento de experimentos com o Método de
Taguchi. Por fim, foi possível comparar o comportamento da cunha com os
resultados de RC. A maior influência sobre o desempenho de solda foi exercida
pela profundidade de penetração enquanto a velocidade de rotação foi um
parâmetro menos significativo. Com a minimização da cunha obteve-se uma
resposta benéfica no desempenho de solda, o que foi associado à ausência de
uma região potencial para a nucleação de trincas. Apesar de descontinuidades
inerentes, resultados promissores foram encontrados para juntas de alumínio
para aplicações aeroespaciais.
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Novas estratégias para a otimização em problemas com múltiplas respostas: um estudo no tratamento de efluentes fenólicos / New strategies for optimizing multiple responses: a study in the treatment of phenolic wastewaterFreitas, Ana Paula Barbosa Rodrigues de [UNESP] 05 July 2016 (has links)
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Previous issue date: 2016-07-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi a aplicação de técnicas de otimização envolvendo múltiplas respostas em problemas da área ambiental, mais especificamente no tratamento de efluentes fenólicos. O efluente é oriundo da Brasquip Ambiental, que é uma empresa de engenharia e prestação de serviços. A otimização foi realizada pelos métodos GRG, Desirability, Simulação Monte Carlo Estocástica. Neste trabalho o efluente foi degradado por meio de processos alternativos; os Processos Oxidativos Avançados. No estudo desenvolvido, as variáveis respostas utilizadas foram: % remoção de Carbono Orgânico Total, Demanda Química de Oxigênio e Fenóis Totais. A função Compromisse Programming foi aplicada como um método de aglutinação, sendo também, comparada com os resultados obtidos pelos métodos Desirabilty. As variáveis de decisão, ou variáveis entrada, obtidas na Simulação Monte Carlo Estocástico, nos métodos Desirability e GRG foram validados experimentalmente. Logo, as remoções obtidas para o Arranjo Ortogonal de Taguchi e do Método de Superfície de Resposta (MSR) foram significativas para as variáveis respostas obtidas, mas a remoção de fenóis totais foi a mais significativa. No estudo estocástico, os valores experimentais obtidos do Taguchi e do MSR também apresentaram-se relevantes para a mineralização do efluente fenólico. Os resultados obtidos experimentalmente da Simulação Monte Carlo Estocástica apresentaram próximos dos obtidos pelo software, sendo que o algoritmo utilizado foi o Optquest. A função CP apresentou valores relevantes para a degradação do efluente, sendo que para este trabalho a Simulação Monte Carlo Estocástica e GRG foram mais significativos se comparado com método Desirability. / The objective of this work was the application of multiple optimization techniques involving responses from environmental problems, specifically in the treatment of phenolic wastewater. The effluent comes from the Environmental Brasquip, which is an engineering company and services. The optimization was performed by the methods GRG, Desirability, Monte Carlo Simulation Stochastic. In this work the effluent was degraded by alternative processes; the Advanced Oxidation Processes. In the study, the variables used responses were:% removal of Total Organic Carbon, Chemical Oxygen Demand and Total Phenols. The Compromisse Programming function has been applied as an agglutination method, also being compared with the results obtained by Desirabilty methods. The decision variables, or variables input obtained in Monte Carlo simulation Stochastic in Desirability methods and GRG were validated experimentally. So removals obtained for Orthogonal Arrangement Taguchi and Response Surface Method (RSM) were significant to the variable responses obtained, but the removal of total phenols was the most significant. In stochastic study, the experimental values and the Taguchi MSR also showed themselves relevant for the mineralization of the phenolic effluent. The experimental results of Monte Carlo Simulation of Stochastic presented near obtained by software, whereas the algorithm used was OptQuest. The CP function showed significant values for degradation of effluent, and for this work to Monte Carlo Simulation Stochastic and GRG were more significant compared with Desirability method.
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Novas estratégias para a otimização em problemas com múltiplas respostas : um estudo no tratamento de efluentes fenólicos /Freitas, Ana Paula Barbosa Rodrigues de. January 2016 (has links)
Orientador: Messias Borges Silva / Coorientador: Aneirson Francisco da Silva / Coorientadora: Marcela Aparecida Guerreiro Machado / Banca: Fernando Augusto Silva Marins / Banca: Antonio Fernando Branco Costa / Banca: Fabrício Maciel Gomes / Banca: Lívia Melo Carneiro / Resumo: O objetivo deste trabalho foi a aplicação de técnicas de otimização envolvendo múltiplas respostas em problemas da área ambiental, mais especificamente no tratamento de efluentes fenólicos. O efluente é oriundo da Brasquip Ambiental, que é uma empresa de engenharia e prestação de serviços. A otimização foi realizada pelos métodos GRG, Desirability, Simulação Monte Carlo Estocástica. Neste trabalho o efluente foi degradado por meio de processos alternativos; os Processos Oxidativos Avançados. No estudo desenvolvido, as variáveis respostas utilizadas foram: % remoção de Carbono Orgânico Total, Demanda Química de Oxigênio e Fenóis Totais. A função Compromisse Programming foi aplicada como um método de aglutinação, sendo também, comparada com os resultados obtidos pelos métodos Desirabilty. As variáveis de decisão, ou variáveis entrada, obtidas na Simulação Monte Carlo Estocástico, nos métodos Desirability e GRG foram validados experimentalmente. Logo, as remoções obtidas para o Arranjo Ortogonal de Taguchi e do Método de Superfície de Resposta (MSR) foram significativas para as variáveis respostas obtidas, mas a remoção de fenóis totais foi a mais significativa. No estudo estocástico, os valores experimentais obtidos do Taguchi e do MSR também apresentaram-se relevantes para a mineralização do efluente fenólico. Os resultados obtidos experimentalmente da Simulação Monte Carlo Estocástica apresentaram próximos dos obtidos pelo software, sendo que o algoritmo utilizado foi o Optqu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this work was the application of multiple optimization techniques involving responses from environmental problems, specifically in the treatment of phenolic wastewater. The effluent comes from the Environmental Brasquip, which is an engineering company and services. The optimization was performed by the methods GRG, Desirability, Monte Carlo Simulation Stochastic. In this work the effluent was degraded by alternative processes; the Advanced Oxidation Processes. In the study, the variables used responses were:% removal of Total Organic Carbon, Chemical Oxygen Demand and Total Phenols. The Compromisse Programming function has been applied as an agglutination method, also being compared with the results obtained by Desirabilty methods. The decision variables, or variables input obtained in Monte Carlo simulation Stochastic in Desirability methods and GRG were validated experimentally. So removals obtained for Orthogonal Arrangement Taguchi and Response Surface Method (RSM) were significant to the variable responses obtained, but the removal of total phenols was the most significant. In stochastic study, the experimental values and the Taguchi MSR also showed themselves relevant for the mineralization of the phenolic effluent. The experimental results of Monte Carlo Simulation of Stochastic presented near obtained by software, whereas the algorithm used was OptQuest. The CP function showed significant values for degradation of effluent, and for this work to Monte... (Complete abstract click electronic access below) / Doutor
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Investigating different types of variability in food production systemNoorwali, Ammar January 2016 (has links)
A high level of competition in the food industry, specifically in the Middle East and the UK has forced companies to improve their processes by reducing lead time, waste, and costs and increasing production efficiency. The main challenge to the achievement of the process improvement objectives is the high level of process variability. Therefore, this research investigates the different types of variability in food production system and proposes a methodology to reduce the effect variability in food production system. The variability can be caused by several factors, for instance, in biscuit production lines variability can be induced due to short breakdown and long breakdown, variable processing times, variable temperature, etc. The proposed approach addresses process time variability issues associated with both make-to-stock (MTS) and make-to-order (MTO) manufacturing environments using an iterated approach. The proposed methodology integrates process mapping, (which is a lean tool for identifying value added and non-value added activities), discrete event simulation (to mirror the real production line), Taguchi orthogonal arrays (to generate different scenarios in order to investigate the effect of variability on the simulation model), correlation analysis (to identify the highest variability factors), and the rule based system (to improve food production system performance based on identified key performance indicators (KPIs)). The research uses a biscuit production line as a case study to validate the proposed methodology. The application of the proposed approach determines that the highest effected KPI is %working. The results showed that after implementation of the rule-based system, key performance improved in high variable areas. Results analysis based on before scenario shows that %working performance indicator is highly effected by variable temperature, speed, and breakdown factors for high variable areas such as baking, cooling, aligning, and packing. Based on identified factors and high variable areas, rules are developed by applying standardisation setting (SOP, WI, PP) in high variable areas and the results shows %working improved in baking by 4.78%, in cooling by 16.06%, in aligning by 0.35%, in packing machine1 by 2.5%, in packing machine2 by 2.37%, in packaging1 by 3.35%, and in packaging2 by 3.16%. The integrated method allow quick response , control the environment without production interruption, reduce number of experiments , and reducing variability in high variable areas, which narrowed the improvement in the required areas and increased its effectiveness.
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Application of bioprocess-supercritical fluid extraction techniques in the production and recovery of some selected bioproductsTaiwo, Abiola Ezekiel January 2020 (has links)
Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2020 / The use of bioproducts in different commercial sectors such as medicine, agriculture, cosmetics, food, and chemical industries motivates the need for easy production and recovery techniques of bioproducts at laboratory and pilot scale. This study aims at the production and recovery of some selected bioproducts using supercritical fluid extraction techniques. Three products are chosen as case studies: these are ethanol, acetoin, and vanillin, since the ease of separation is influenced by the concentration of the product in the broth, these compounds were selected based on their concentration in the fermentation broth, according to literature sources. A standard method was developed in a spectrophotometer for quantifying the targeted product in the broth, while the product recovery studies was carried out using a supercritical fluid extraction pilot plant. Saccharomyces and Bacillus species were chosen for the bioproduction of the selected bioproducts. Experimental design and statistical analysis of results were carried out using response surface methodology (RSM) and artificial neural network (ANN). Studies on each of the selected bioproducts are as justified in the paragraphs below.
Bioethanol production has recently become an increasing trend in research, with a focus on increasing its economic viability. Hence, the need to develop a low-cost fermentation medium with minimum redundant nutritional supplements, thereby minimizing the costs associated with nutritional supplements whereby inoculum preparation becomes necessary for ethanol production. Corn steep liquor (CSL) in glucose fermentation by Saccharomyces Type 1 (ST1) strain and Anchor Instant Yeast (AIY), which are low-cost media, are used as replacements for yeast extract (YE). The fermentation process parameters were optimized using artificial neural networks (ANN) and the response surface methodology (RSM). The study shows that for CSL, a maximum average ethanol concentration of 41.92 and 45.16 g/L representing 82% and 88% of the theoretical yield were obtained after 36 h of fermentation in a shake flask for ST1 and AIY respectively. For YE, ethanol concentration equivalent to 86% and 88% of theoretical yield were obtained with ST1 and AIY respectively after 48 h. Although, ANN predicted the responses of ethanol yield better than RSM, optimum conditions for ethanol production were better predicted by RSM.
The consumers’ preference for ‘naturally’ produced aromas drives the development of bioproduction of acetoin from glucose with a view to optimize its production. The results revealed that by using a cheap nitrogen source, corn steep liquor, the yield of acetoin was similar to those of yeast and beef extracts. Furthermore, it was shown that by using Box-Behnken design, the optimum parameters such as glucose concentration, corn steep liquor, and inoculum size to maximize the concentration of acetoin produced were 78.40 g/L, 15.00% w/v and 2.70% v/v respectively. The validated concentration of acetoin produced in a triplicate analysis, 10.7 g/L, was 0.06% less than the predicted value.
Increasing awareness of consumers of healthy, eco-friendly flavors and fragrances motivates the bioproduction of vanillin. The interactive effects of three variables on vanillin yield were evaluated by response surface methodology (RSM) with Box-Behnken design (BBD) model. The results showed the optimum conditions for the biotransformation of ferulic acid into vanillin can be achieved with maximum overall desirability (D) of 1.0 and a significant (p<0.05) quadratic model with regression coefficient (R2) of 0.995. Corn steep liquor, initial ferulic acid concentration and pH significantly influence the concentration of vanillin in the broth. The results in triplicate experiments confirmed vanillin yield of 386 mg/L after validation, which was in agreement with the prediction of the model. The maximum vanillin yield of 384.40 mg/L was predicted when corn steep liquor, ferulic acid concentration and pH were 7.72 g/L, 2.33 g/L, and 9.34 respectively.
Fermentation system in a bioreactor has been proven to be an efficient system for the study of controlled fermentation variables when compared to a shake flask study. The influence of agitation, aeration, time and pH were analysed by Taguchi orthogonal array design for the upscale of acetoin in a bioreactor. The optimized parameters in 1.3L of fermentation vessel were as follows: 300 rpm agitation, 1.5 slpm aeration; 2 days’ fermentation time and 6.5 pH value. Agitation with above 70% was the most contributing factor and other variables were less than 30% in the percentage analysis of variance of each fermentation variables in the batch study of acetoin. A fourfold gain in acetoin titre (42.30 g/L) was obtained with the same substrate concentration in a lab-scale bioreactor on scaling up when compared with the shake flask batch study. The validated acetoin concentration of 41.72 g/L was obtained after a triplicate experiment to confirm the possibility of reproducing acetoin using the optimized conditions.
Many separation techniques have been proven to recover value-added products from fermentation broth with a preference for several methods above other and new techniques that are emerging. Supercritical fluids separation using CO2 is one such technique. The feasibility of acetoin concentration and recovery was studied in supercritical CO2 pilot plant with pressure ranges of 100 to 300 bar, CO2 feed rate of 5 to 15 kg/h, at a process temperature of 37 and 80 °C in simulated and fermentation broth, respectively. The validated conditions for the fractionation of acetoin by supercritical fluid extraction (SFE) were determined as follows: extraction pressure, 300 bar; CO2 feed rate, 15 kg/h; extraction temperature 37 °C; and fractionation time of 30 minutes. At these operating conditions, the percentage recovery of acetoin with respect to the feed solution at the raffinate for the simulated and actual ermentation broth was 77.8% (0.20 g/L) and 77% (0.15 g/L) respectively. A two-fold extract increase was obtained after 30 minutes of fractionation.
The study provides the technical feasibility and the base case data which are critical to the development and design of processes for production and recovery of acetoin. The lesson gleaned from this study may be extended to develop processes for the production and recovery of other bioproducts (ethanol and vanillin).
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Méthode d'évaluation d'assemblages industriels en aluminium liés par adhésifs structurauxLeduc, Bruno 20 April 2018 (has links)
Ce mémoire entame le développement d’une méthode d’évaluation d’assemblages en aluminium liée par adhésifs structuraux dans un contexte d’ingénierie du secteur industriel. Les travaux ont pour but de fournir à l’entreprise Services Précicad inc. des outils de conception applicables sur le véhicule électrique Kargo. Plus spécifiquement, des séries d’essais expérimentaux sont réalisées sur des échantillons ASTM au moyen de plans d’expériences employant la méthode Taguchi pour étudier l’incidence des conditions de préparation manufacturière sur la résistance mécanique et pour faire un dépistage de produits commerciaux. La famille des méthacrylates est alors privilégiée pour répondre aux besoins de flexibilité d’utilisation et de préparation de surface. Ensuite, différents modèles de calculs analytiques sont étudiés et une analyse paramétrique est réalisée sur le joint en cisaillement à simple recouvrement (SLS). Le modèle du joint sandwich simplifié de Bigwood et Crocombe est choisi comme outil de calculs de prédimensionnement de joints génériques, cependant une bonne connaissance des conditions limites est nécessaire. L’approche de simulation par la méthode des éléments finis en mécanique des milieux continus est alors recommandée. D’importantes difficultés de convergence des résultats des contraintes sont identifiées avec cette théorie, entre autres par la présence de singularités numériques aux interfaces du volume de l’adhésif. Des techniques de modélisation simplifiées, utilisant les outils du logiciel NX Nastran, sont ensuite testées et l’outil Surface-Gluing est alors proposé pour permettre la simulation de joints qui reflètent les caractéristiques de modélisation « industrielles » de Précicad. Finalement, une méthode de mesure des propriétés élastiques in situ pour adhésifs flexibles, compensée au moyen d’analyses par éléments finis, est développée afin de pouvoir réaliser une caractérisation avec un extensomètre conventionnel, tout en préservant la précision souhaitée. Ainsi, il a été possible d’isoler les modules de cisaillement et de tension de l’adhésif H8000. / This thesis initiates the development of a structural assessment method for aluminium adhesively bonded joints, intended for the industrial engineering businesses sector. The present work is devoted to the company Services Précicad inc, who needs design tools that can be used for its Kargo electric vehicle assemblies. In particular, the Taguchi design of experiment method is used to study the effects of joint conditioning on the static strength of different ASTM samples configurations. Commercially available products are screened out during the process. Thus, methacrylates is found to be the best adhesive chemical category for Précicad design and manufacturing needs. Subsequently, a review of different analytical models is carried and the Bigwood & Crocombe sandwich model is selected to perform a parametric analysis on the Single Lap Shear joint (SLS). The simplified version of the sandwich model was found to be the best suited for pre-sizing generic forms of adhesive joints, although a good knowledge of the boundary conditions is mandatory to make a realistic assessment. Consequently, the standard continuum mechanics finite element method is recommended for most joints analysis. However, major convergence difficulties can be found when using this theory, partly due to the presence of numerical singularities in the adhesive domain. Several simplefied modelling techniques using NX Nastran are tested on the SLS joint and the Surface-Gluing tool is proposed for evaluating complex “industrial” meshes such as the ones used by Precicad. Finally, a method for measuring in situ elastic properties of flexible adhesives with finite element analysis compensation is developed for achieving a complete characterization with a conventional clip gauge. Thus, it has been possible to measure the shear and tensile modulus of the H8000 adhesive.
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A Method for Simulation Optimization with Applications in Robust Process Design and Locating Supply Chain OperationsIttiwattana, Waraporn 11 September 2002 (has links)
No description available.
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Tillståndsövervakning av rullningslager med hjälp av E-näsaKristiansen, Pontus, Postnikov, Roman January 2018 (has links)
I dagsläget finns det ingen standardiserad metod för att mäta en enhets tillstånd medhjälp av dofter. Vid tillståndsövervakning av rullningslager är vibrationsmätning denmest dominanta metoden. I samband med vibrationsmätning används i vissa falltemperaturövervakning för att få en bättre insikt på rullningslagrets tillstånd. I det härarbetet undersöks de om en elektronisk näsa kan avgöra ett rullningslagers tillstånd.Innan några mätningar påbörjas monterades en elektronisk näsa ihop i ett hölje sombestår av ett kretskort, metalloxid-sensorer och en fläkt för att styra dofter med ettkonstant flöde mot sensorerna. Den elektroniska näsan styrs av en Arduino Nanomikrokontroller. Utöver e-näsan sättes en enhet ihop tillhörande två temperaturgivareoch en luftfuktighetsgivare som styrs av en Arduino UNO. Enhetens syfte är att kunnakontrollera de rådande förhållandena vid mätningar och för att leta någon form avkorrelation mot e-näsan vid eventuella utslag. Förstörande prover av kullager utfördesför att se om e-näsan reagerar innan ett lagerhaveri. Testerna gjordes i en öppen samtsluten miljö och tre stycken olika oljor används för att smörja lagret. Detta för att seom e-näsan reagerar olika beroende på vilken olja som används. En undersökningutförs ifall den elektroniska näsan kan separera på de tre oljorna som används ilagertesterna. För att utvärdera mätresultaten används Excel och Minitab, därprincipalkomponentanalyser genomförs på all mätdata. Efter att alla lagerprover harverkställts utfördes en uppföljning av rullningslagrena för att studera deras tillstånd,detta genom ett optiskt mikroskop.Det framgår i rapporten att med hjälp av analysmetoden PCA syns det att denelektroniska näsan kunde skilja på hydraulolja, motorolja och växellådsolja. Utslag iPCA för de olika mätserierna blev inte identiska men det blev tydligaklusterindelningar hos samtliga mätserier. Genomförd studie visade att med delagerhaveri samt temperaturer går det inte att avgöra ett kullagers tillstånd med hjälpav en elektronisk näsa. Eftersom att de specifika gas-sensorerna som användes till enäsaninte gav någon form av utslag vid mätningarna. Den elektroniska näsanreagerade däremot vid totalhaveri av kullager, vilket är för sent i ett förebyggandeunderhållsperspektiv. Detta medförde att den elektroniska näsan inte kan användas förtillståndsövervakning av det specifika kullagret som användes vid denna studie. / At present, there is no standardized method of measuring a device's condition with thehelp of odors. In condition monitoring of rolling bearings, vibration measurement isthe most dominant method. In case of vibration measurement, temperature monitoringis used in some cases to get a better insight into the condition of the bearing. In thiswork, it is investigated whether an electronic nose can determine the condition of arolling bearing.Before any measurements began, an electronic nose is assembled in a housingconsisting of a circuit board, metal oxide sensors and a fan for stearing odors with aconstant flow towards the sensors. The electronic nose is controlled by an ArduinoNano which is a microcontroller. In addition to the e-nose, a unit is connected to twotemperature sensors and a humidity sensor controlled by an Arduino UNO. The unit'spurpose is to monitor the status and to look for any kind of correlation with the e-nosein case of any possible findings. Destructive specimens of ball bearings are performedto see if the e-nose responds prior to a bearing failure. Tests are conducted in an openand closed environment and three different oils are used to lubricate the bearings.This to see if the e-nose acts differently depending on the oil that is used. Aninvestigation is conducted if the electronic nose can separate the three different typesof oils that is used in the destructive bearing tests. To evaluate the measurementresults, Excel and Minitab are used, where principal component analysis is performedon all measurement data. After all bearing tests have been performed, a follow-up ofthe rolling bearings condition is performed, this through an optical microscope.The report shows that using the PCA analysis method, it appears that the electronicnose could distinguish between hydraulic oil, engine oil and gear oil. In the PCA forthe different measurement series the results did not become identical, but clusterdivisions became clear in all measurement series. Completed study showed that withthese bearing failures and temperatures, it is not possible to determine the condition ofthis ball bearer using an electronic nose. Because the specific gas sensors used for thee-nose did not give any kind of impact during the measurements. On the other hand,the electronic nose responded to a total failure of a ball bearing, which is too late in apreventative maintenance perspective. Therefore, the electronic nose cannot be usedfor condition monitoring of the specific ball bearing used in this study.
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應用統計方法找尋配方之研究蔡淑茜, Tsai, Shu-Chien Unknown Date (has links)
本研究嚐試找出果凍的最適配方,利用品質機能展開將顧客需求和技術項目結合,找出顧客所重視的技術項目,再依此規劃實驗收集資料。以田口方法和迴歸分析法對數據分析,以提出最適配方。
利用田口方法和迴歸分析法兩種方法找尋最適配方,發現依照不同品質特性所找出的最適配方結果是不相同的,而同時考慮兩種品質特性整體損失函數所找出的最適配方,才能使整體期望損失估計值最小(小於兩個品質特性各別所找出最適配方期望損失估計值的加總)。
由於產品時常有多個品質特性,建議找最適配方時,能同時考量各品質特性的總損失,唯有如此才能找到真正使損失最低的最適生產組合。 / The research goal is to try to find optimal setting combination of one product. We take advantage of QFD (Quality Function Deployment) method to combine the needs of customers and producing technologies; by this, we can tell which technologies are more important for customers’needs. After knowing which technologies are important, we could order an experiment to collect raw data. Using Taguchi Method and Regression Analysis Method to analyze the raw data, we can extract optimal solutions.
We found that we could get different optimal solution by different character of a product. Therefore, only considering all characters of a product at the same time, we can get the really optimal setting combination; or we just could get sub optimal setting combinations.
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