The aim of this study was to evaluate employee commitment to achieve the primary objective, which was to evaluate employee commitment towards product and process quality. Employees who are engaged in their work and committed to their organisations give companies crucial competitive advantages – including higher productivity, better quality products and lower employee turnover. A thorough literature study was conducted by using the views of different authors and combining them. The concept of quality was defined by making use of the five quality gurus; Deming, Juran, Feigenbaum, Crosby and Ishikawa. The fourteen principles of quality, developed by Deming, were presented in Table 2.1. These principles had the goal of increased productivity, with less rework, less waste of manpower and material resources, resulting in a reduction of costs, to in turn give the organisation greater market share and ultimately better competitive position, by improving the overall quality of an organisation’s work processes. The concept of employee and organisational commitment was defined, and from this study it is evident that employee commitment towards the company is positive and therefore should have a positive effect on their operating environment. The product process flow for this manufacturing concern were discussed to give an overall view of the production processes used in this organisation. An empirical study was completed using a questionnaire survey to determine employee commitment at a manufacturing concern in Gauteng. The questionnaire used for this study was designed to focus on commitment towards internal quality only, to specifically evaluate employee perspective towards product quality, as well as the commitment towards the organisation. Analysis of the responses showed the questionnaire to be reliable and valid. Respondents indicated that they are committed towards the organisation in general across all constructs, but a lack in management trust was a predominant sentiment. The quantitative analysis showed that after a factor analysis was done on the two sections of the questionnaire, four factors for each section were considered as meaningful. These factors were: Affinity, quality awareness, autonomy and corporate image (employee commitment - section B) and employee commitment, task performance, job satisfaction and contextual performance (company relationship – section C). This indicated strong employee commitment towards the organisation. The qualitative results had four areas that all respondents felt needed some attention, and loaded negative towards the organisation. These were HR (trust in management, competency, communication and company culture), skills development, employee development and BBBEE. Thus, drawing conclusions from quantitative results alone could give a company a false sense of employee commitment towards the company and therefore overlook the importance of the roles that employees play in executing strategic plans. Conclusions regarding the findings of the research study were presented and recommendations for this organisation were made. These recommendations are merely a guideline that correlates directly to the empirical analysis made. The research study was evaluated against the primary and secondary objectives with the conclusion that both were achieved. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

La présente étude traite de l’éco-conception d’une pièce structurale, de type poutre tubulaire, en stratifié bio-composite à base de fibres de lin. A cette pièce à concevoir est associé un cas de charge mécanique combinant flexion et torsion et une tenue face aux produits détergents-décontaminant utilisés en environnement médical. Cette étude a pour objectif de montrer la faisabilité d’employer comme architecture de renfort, une mèche de lin pour la réalisation de la pièce. Ce renfort a la particularité d’être constitué de fibres alignées dont la cohésion est assurée par la présence d’un liant par opposition aux fils constituées de fibres retordues. Tout d’abord, pour établir un cahier des charges de fabrication à partir de ceux déjà en vigueur, le comportement mécanique du bio-composite à l’échelle du pli, puis à celui du stratifié et enfin à l’échelle de la poutre stratifié a été modélisé et des critères de conception et de dimensionnement portant sur la rigidité en flexion et en torsion ont été développés de façon analytique. Associée à cette approche et au choix du renfort, le procédé d’enroulement filamentaire a été retenu pour la mise en oeuvre de la pièce. Afin de montrer la compatibilité de la mèche en entrée et le procédé sélectionné, une étude du comportement en traction de la mèche visant à étudier l’effet des paramètres du procédé sur les propriétés mécaniques de la mèche a été réalisée. Cette deuxième phase a été poursuivie par la réalisation de prototypes, suivant le cahier des charges de fabrication établit, qui ont ensuite été analysés en termes de qualité et de performances mécaniques. La corrélation entre ces résultats et ceux obtenus par l’étape de dimensionnement a permis de valider l’approche. Enfin, dans le but d’intégrer l’interaction avec l’environnement opératoire dans le dimensionnement de la pièce, une étude de la durabilité a été réalisée. Celle-ci permet d’établir des stratégies de dimensionnement pour répondre à l’application. / This study aims at eco-designing a structural part, of a hollow beam type, using a laminated flax fibre based bio-composite. The part needs to satisfy a given bending and torsion load case and show compatibility with the cleaning products used in the medical environment. The objective of the study is to investigate the potential of using a flax tow as the reinforcement input for the manufacturing of the beam. The particularity of the reinforcement is that it consists of an assembly of aligned flax fibres held together by a binder as opposed to spun yarns. First, in order to establish the required manufacturing specifications, the mechanical behaviour of the bio-composite at the ply scale, at the laminated and finally at the laminated beam scale was modelled. From this modelling, design and dimensioning criteria based on bending and torsional stiffness were developed analytically. Combining this approach with the choice of the reinforcement, the wet-filament winding process was chosen to manufacture the part. Thus, the tensile behaviour of the flax tow was studied in relation to the process parameters to demonstrate their compatibility. This second phase was followed by the manufacturing of prototypes according the established specifications which were then analysed in terms of quality and mechanical performance. The correlation between experimental results and the model predictions was used to validate the dimensioning approach. Finally and in order to incorporate the interaction of the part with the environment, a durability study was conducted. The latter allows to put forward different dimensioning strategies to meet the required specification.

No description available.

The vast majority of chemical products, both in number and volume, are produced by batch processes. Recent studies show that only six percent of the batch processes were satisfactorily replaced by continuous processes. This clearly shows the importance and permanence of such processes. These plants have a basic characteristic of intermittent production of a product with non-stationary operation, including steps of loading, processing, cleaning and drainage, what makes the project complex. Its use is recommended, or for technological reasons or to meet the need for a dynamic and uncertain market, as it is the case of products with high added value and small demand. An important aspect of this type of plant is its flexibility in producing multiple products in a unique plant. The batch operations are economically justified when a large number of products are produced using similar production paths. Due to the difficulty of predicting the peak and the extension of demand, such settings are frequently modified plant and equipment is usually small and versatile and can be used by a large number of products. Power must be flexible enough to adapt to market needs and product life cycle is usually short. Brazil ranks third in world ranking in sales of personal care products, perfumes and cosmetics. The industry in this sector, in the two study reaches, each year, more consumers. The currently complex and competitive global market requires that companies seek to optimize processes, reduce costs and achieve economies of scale. In view of this, we have the developed a mathematical model of large, from real data, obtained in a Personal Hygiene Industry, providing a practical application to the work on Design and Production Scheduling of Multipurpose Batch Plants, from Professor João Soletti, which enables to perform planning and design of this type of plants. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A grande maioria dos produtos químicos, certamente em número e provavelmente em valor, se não em volume, é produzida por processos em batelada. Recentes estudos mostram que apenas seis por cento dos processos em batelada foram satisfatoriamente substituídos por processos contínuos. Isto mostra claramente a importância e permanência de tais processos. Estas plantas têm como característica básica a produção intermitente de um determinado produto, com operação não estacionária, incluindo etapas de carga, processamento, drenagem e limpeza, o que dificulta o seu projeto. Sua utilização é recomendada, ou por razões tecnológicas ou para atender a necessidade de um mercado incerto e dinâmico, como é o caso de produtos de alto valor agregado e de pequena demanda. Um importante aspecto desse tipo de planta é a sua flexibilidade na produção de múltiplos produtos em uma única planta. As operações em batelada são economicamente justificadas quando um grande número de produtos é realizado utilizando caminhos de produção similares. Devido à dificuldade da previsão do pico e da extensão da demanda, as configurações desse tipo de planta são frequentemente alteradas e os equipamentos são, geralmente, pequenos e versáteis, podendo ser utilizados por um grande número de produtos. A alimentação deve ser flexível, o suficiente, para se adaptar à necessidade do mercado e o ciclo de vida do produto é, geralmente, curto. O Brasil ocupa o terceiro lugar no ranking mundial em vendas de produtos de higiene pessoal, perfumaria e cosméticos. A indústria desse setor, objeto do estudo, atinge, a cada ano, mais consumidores e a natureza do sistema de produção nesse setor é por processo em batelada. Com a atual complexidade do mercado globalizado e competitivo, é necessário que as empresas busquem otimizar processos, reduzir custos e obter ganhos de escala. Em vista disto, desenvolveu-se um modelo matemático de grande porte, a partir de dados reais, obtidos em uma Indústria de Higiene Pessoal, possibilitando uma aplicação prática à tese sobre Dimensionamento e Programação da Produção de Plantas Multipropósito em Batelada, do Prof. João Soletti, que indica como realizar o planejamento e projeto de unidades fabris.

Ces travaux de thèse s’intéressent aux outils de simulation rapide de la fabrication d’un pneumatique. L'objectif est de prédire le mouvement et la position des éléments constitutifs du pneumatique, lors de leur mise en conformation, en prenant en compte les déformations induites par les actions mécaniques associées. Ces travaux s’appuient sur la mise en place d’un algorithme visant à modéliser le gonflement d’un outillage et la mise en place d’un modèle de déformation d’un système de formes géométriques aux caractéristiques mécaniques différentes. L'algorithme de gonflement de l’outillage se base sur la théorie des membranes inextensibles et son industrialisation est validée pour des dimensions standards de pneumatiques. La méthode Masse-Ressort est retenue pour réaliser la déformation de formes géométriques afin d’obtenir des résultats de déformation en temps réel. Dans ces travaux, cette méthode est adaptée aux matériaux d’un pneumatique à partir de travaux de caractérisations géométrique et mécanique validés par comparaison aux Éléments Finis. En conclusion, la modélisation développée permet une description à chaque étape du procédé de fabrication. / This thesis deals with fast simulation tools used to manufacture of a tire. The goal is to predict the displacement and position of the components of a tire taking into account the deformations induced by the associated mechanical actions. This work is based on the implementation of an algorithm for modeling the inflation of a tool and the development of a deformation model in order to compute the deformation of geometric shapes taking into account different mechanical properties. The algorithm to model the inflation of the tool is based on the theory of inextensible membranes and its industrialization is validated for standard sizes of tires. Mass-Spring method is used to achieve the deformation of geometric shapes in order to compute deformation in real time. In this work, this method is suitable for materials of a tire from geometric and mechanical characterizations validated by comparison with FEM. To conclude, the developed modelization allows a description for each step of the manufacturing process.

Cette thèse s’intéresse à la fabrication de jonctions magnétiques à effet tunnel organiques. Les MTJ organiques remplacent la barrière par une molécule. Il a fallu d’abord vaincre les problèmes liés à la fabrication de ces MTJ. En effet, ce type de jonction est très fragile du point de vue de sa fabrication, car incompatible avec les solvants. Un nouveau procédé de fabrication a été mis au point. Ce procédé fait appel à de petites « billes » nanométriques dispersées à la surface d’un échantillon. Ce procédé a été utilisé avec succès. Nous avons obtenu une réponse magnétique des échantillons. Des mesures XAS et de magnéto-transport ont été menées sur des jonctions MgO. Une approche in operando innovante a été utilisée. Ces mesures ont démontré que la présence d’oxyde de fer aux interfaces limite la TMR. Pour finir, des mesures SR-PES ont été menées dans le but d’étudier la polarisation d’interface de Cu/MnPc dans le système Cu(100)//Co/Cu/MnPc. Ces mesures ont révélé que cette interface est très fortement polarisée en spin. Les structures qui apparaissent dans les spectres ne peuvent être expliquées par une simple atténuation du signal du cobalt due à la couverture de molécules. / This thesis concerns the fabrication of organic magnetics tunnel junctions. Organic MTJs replace the barrier with a molecule. First, we had to overcome the problems of MTJ manufacturing. Indeed, this type of junction is very fragile from the point of view of its manufacturing because they are incompatible with solvents. A new manufacturing process has been developed. This process uses small nanometric "beads" scattered on the surface of a sample. This method has been used successfully and we obtained a magnetic response of the samples. XAS and magneto-transport measurements were conducted on MgO junctions. An innovative in operando approach was used. These measurements revealed that the presence of oxide at the interfaces limits the TMR. Finally, SR-PES measurements were carried out in order to study the Cu/MnPc interface polarization in the Cu (100)//Co/Cu/MnPc system. These measurements revealed that this interface is strongly spin polarized. Structures appearing in the spectra cannot be explained by a simple attenuation of the cobalt signal due to molecule coverage.

O presente trabalho trata da análise experimental de um sistema de monitoramento baseado na técnica de fusão de sensores, aplicado em uma retificadora cilíndrica externa. A fusão é realizada entre os sinais de potência e emissão acústica para obtenção do parâmetro FAP (Fast Abrasive Power) através do método desenvolvido por Valente (2003). Através da simulação de problemas encontrados nos processos de retificação (falha de sobremetal, colisão, desbalanceamento e vibração), foram captados os sinais de potência e emissão acústica e a partir destes gerado o parâmetro FAP, comparando seu desempenho, na detecção dos problemas, com os outros dois sinais. Para a análise foram construídos os gráficos das variações dos sinais em relação ao tempo de execução do processo e os mapas do FAP e acústico. O sistema de monitoramento avaliado tem como característica baixa complexidade de instalação e execução. Os dados experimentais revelam que o FAP apresenta uma velocidade de resposta maior que a potência e levemente amortecida em relação à emissão acústica. O nível do seu sinal é igual ao da potência mantendo-se homogêneo durante o processo, ao contrário da emissão acústica que pode ser influenciada por diversos outros parâmetros, tais como geometria da peça, distância do sensor, montagem do sensor, entre outros, que independem da interação ferramenta-peça. O resultado é uma resposta dinâmica e confiável, associada à energia do sistema. Estas características são interessantes para o monitoramento de processos de retificação (excluindo a dressagem) sendo superiores àquelas apresentadas isoladamente pelos sinais de potência e emissão acústica. / The present study deals with an experimental analysis of a monitoring system based on a sensor fusion strategy applied to a cylindrical grinding machine. It comprises a fusion of the power and acoustic emission signals and has as main goal to obtain the FAP (Fast Abrasive Power) using the method developed by Valente (2003). Initially, the power and acoustic emission signals were captured under operational dysfunction conditions during the grinding process (stock imperfection, collision, unbalancing e vibration). Then, based on these signals, the FAP parameter was generated and its capability in characterizing operational dysfunctions evaluated against the performance of an individual analysis of the power and acoustic emission signals. For this analysis, FAP and acoustic maps plus plots showing the FAP signals vs. working time were implemented. The experimental data revealed that the FAP presents a faster response than the power signal and a slightly dumped response when compared against the acoustic signal. The signal level of the FAP is similar to the power signal and is homogenous during the machining process. On contrary to the FAP, the acoustic emission signal may be affected by parameters that are not related to the tool-workpiece interactions, workpiece geometry and sensor positioning. The dynamic response of FAP is reliable and linked to the energy of the system. Finally, it should be highlightened that the monitoring system based on the FAP parameter presents low complexity in both implementation and execution. Such characteristics are superior to those observed when using either the power or acoustic emission signals and highly valuable in a system designed to monitor grinding processes.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-08T15:39:05Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertacaoMestrado-LubnniaMorais.pdf: 1068810 bytes, checksum: 0fb0e8db76865a85052555adeb36a048 (MD5) / Made available in DSpace on 2016-07-08T15:39:05Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertacaoMestrado-LubnniaMorais.pdf: 1068810 bytes, checksum: 0fb0e8db76865a85052555adeb36a048 (MD5) Previous issue date: 2015-03-13 / A globalização e os avanços tecnológicos têm forçado as empresas a aumentar a produtividade e reduzir custos. Ao mesmo tempo, os clientes estão cada vez mais exigindo melhores produtos considerando atributos tangíveis (ex.: aroma, cor, sabor, textura, entre outros) e intangíveis (ex.: marca, comércio justo e responsabilidade ambiental). O café é um dos produtos agrícolas mais importantes do mercado mundial, considerado a força propulsora do desenvolvimento sócio-econômico para muitas regiões, além de ser produzido em todos os continentes. Vale ser ressaltado que o café é uma das bebidas mais consumidas no mundo, sendo a segunda maior commodity 1 negociada depois do petróleo. Para a economia brasileira, o café é uma atividade tradicional e de grande inserção no mercado internacional. É responsável pela geração de um grande número de empregos em todos os setores da economia, indo desde os setores de máquinas, equipamentos e insumos, passando pela produção no campo e pela indústria, até o setor de serviços, como logística e comércio. Atualmente o Brasil consolida a posição de maior produtor e exportador mundial de café, sendo responsável por 30% do mercado internacional de café. Logo é necessário analisar cada vez mais o processo de produção do café, a fim de aumentar a capacidade de produção do sistema, bem como reduzir simultâneamente os custos, sejam devidos à operação, manutenção, pontualidade na execução das tarefas ou ociosidade do equipamento. Tal análise quando corretamente aplicada, é capaz de evidenciar os principais pontos de gargalo, sobre os quais os gerentes de produção devem manter o foco e otimizá-los a fim de aumentar a vantagem competitiva de empresa. A avaliação do desempenho do processo de manufatura é de grande importância para detectar problemas no processo de produção (ex.: gargalos), bem como elementos para reduzir os custos, uma vez que as falhas geram custos durante o desenvolvimento, durante a produção e em serviço (B., 2008). A análise de desempenho puro de processos de fabricação assume que os processos não falham. Esta hipótese não é verdadeira, pois a maioria dos processos de fabricação podem continuar as suas operações, mesmo na presença de falhas. Logo, a realização da análise combinada de desempenho e disponibilidade, chamada performabilidade, é essencial. Este trabalho apresenta um modelo estocástico para avaliação de performabilidade e planejamento de processo do fabricação de café com o objetivo de reduzir o custo e o tempo do ciclo de produção. Um estudo de caso industrial mostra a utilidade prática dos modelos e metodologia proposta. Além disso, as estimativas obtidas a partir do modelo mostram que a abordagem proposta é de fato uma boa aproximação para as respectivas medidas obtidas a partir do processo real de fabricação do café. / Globalization and advanced manufacturing technologies have forced manufacturing firms to increase productivity while reducing costs. At the same time, customers are increasingly demanding better products considering tangible (e.g., smell, color, taste, texture, etc.) and intangible (e.g., mark, fair treading environmental responsability) attributes. Coffee is one of the most important agricultural products in the world market, considered the driving force of socio-economic development for many regions, besides being produced on every continent. Is worth be emphasized that coffee is one of the most consumed beverages in the world and is the second largest commodity traded after oil. For the Brazilian economy, the coffee is a traditional activity and of large insertion in the international market. It is responsible for generating a large number of jobs in all sectors of the economy, ranging from the sectors of machinery, equipment and supplies, through production in the field and industry to the service sector, such as logistics and trade. Currently, Brazil consolidates a position as the largest producer and exporter of coffee, accounting for 30% of the international coffee market. Therefore we analyze the coffee production process in order to increase the system’s production capacity and reduce costs simultaneously, are due to the operation, maintenance, on-time execution of tasks or idle equipment. Such analysis when properly applied, is able to show the main points of bottleneck, on which production managers must stay focused and optimize them in order to increase the competitive advantage of the company. The evaluation of the performance of the manufacturing process is very important to detect problems in the production process (ex .: bottlenecks), as well as elements to reduce costs, since faults generate costs in development, production and during service (B., 2008). The pure performance analysis of manufacturing processes assumes that the processes do not fail. This hypothesis is not true, since most manufacturing processes can continue to operate even in the presence of faults. Therefore, the performance of the combined analysis of performance and availability, call performability, is essential. This work presents a stochastic model for performability evaluation and planning of coffee manufacturing process aiming to reduce the cost and time of the production cycle. An industrial case study shows the practical usability of the proposed models and techniques. Besides, the estimates obtained from the model show that the proposed approach is indeed a good approximation to the respective measures obtained from the real coffee manufacturing process.

Orientador: Aline Carvalho da Costa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-21T12:53:49Z (GMT). No. of bitstreams: 1 BozaCondorena_EdwinGuido_D.pdf: 5093932 bytes, checksum: 505cbc2b6c875e35004ad875c0f0ac6a (MD5) Previous issue date: 2012 / Resumo: Na presente tese foram abordados problemas no contexto da produção de etanol de primeira e segunda geração. No caso de etanol de segunda geração foi abordado o problema de melhorar a eficiência da hidrolise enzimática, com as seguintes contribuições: (1) otimização da carga enzimática utilizando técnicas de modelagem por redes neurais. (2) substituição de um modelo com limitações na representatividade dos pontos experimentais obtido por desenho experimental pela superfície de resposta de um modelo de redes neurais que permite a exploração da região do ótimo no espaço de fatores e respostas. Os resultados obtidos mostram (1) boa precisão para a localização das coordenadas da região ótima de trabalho. (2) um mapeamento da evolução do processo com localização do ótimo global utilizando algoritmos genéticos e técnicas de computação evolutiva. No caso dos processos de produção de etanol de primeira geração foi estudado o problema do controle com modelo de um processo de fermentação continua com extração de etanol utilizando vácuo quando não se tem modelo fenomenológico disponível com as seguintes contribuições e resultados: (1) foi desenvolvida uma abordagem que integrou redes neurais artificiais, com o controle preditivo com modelo (MPC). (2) foram desenvolvidos modelos empíricos do processo com redes neurais artificiais (3) foi desenvolvida uma abordagem que utiliza o "conhecimento aprendido" pelas redes neurais o qual e armazenado em pesos sinápticos e bias. (4) foram desenvolvidos vários modelos empíricos de redes neurais para o monitoramento das concentrações de etanol que podem ser utilizados para desenvolver software sensores. (5) foram implementadas diferentes estruturas de controle preditivo com diferentes modelos internos de redes neurais para os controladores, com otimiza dor linear e não linear para o caso de estudo. Nos diferentes capítulos em que foram implementadas estruturas de controle integrando as redes neurais com a tecnologia MPC, se mostrou que, a abordagem desenvolvida e eficiente para os projetos dos sistemas de controle com modelo empírico / Abstract: In this thesis were studied problems in the context of ethanol production of first and second generation. In the case of second generation ethanol was studied the problem of improving the enzymatic hydrolysis efficiency, with the following contributions: 1) optimization of enzyme loading by using modeling techniques based on neural networks, 2) substitution of a model with limited representation capacity of the experimental points which was obtained by using experimental design by the response surface model of a neural network that allows the exploration of the space of factors and responses. The results show: 1) good accuracy in locating the coordinates of the optimum working region, 2) the mapping of the evolution of the process with the location of the global optimum by using genetic algorithms and evolutionary computing techniques. In case of the production of first generation ethanol was studied the problem of the control with process model of a fermentation process with continuous extraction of ethanol by using a vacuum system when there is no a phenomenological model available with the following contributions and results: 1) It was developed an approach in which were integrated artificial neural networks with model predictive control (MPC). 2) It were developed empirical process models by using artificial neural networks 3) It was developed an approach that uses the "learned knowledge" by neural networks which is stored in synaptic weights and bias. 4) It were developed several empirical models of neural networks for monitoring concentrations of ethanol that can be used to develop software sensors. 5) It were implemented different predictive control structures with different internal models based on neural networks for controllers with linear and non-linear optimizer to be applied on the case of study. In the different chapters in which were implemented control structures by integrating neural networks with MPC technology, it was showed that the developed approach is efficient to be applied in the designs of control systems with empirical model / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

Orientadores: Guido Costa Souza de Araújo, Mario Lúcio Côrtes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-21T20:47:12Z (GMT). No. of bitstreams: 1 Santana_MarceloFontes_M.pdf: 4262688 bytes, checksum: 3e2635e36cd3272eb4bd09c07b05bf63 (MD5) Previous issue date: 2012 / Resumo: O resumo, poderá ser visualizado no texto completo da tese digital / Abstract The abstract is available with the full electronic document / Mestrado / Ciência da Computação / Mestre em Ciência da Computação