Made available in DSpace on 2015-10-06T13:02:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-06-25. Added 1 bitstream(s) on 2015-10-06T13:19:10Z : No. of bitstreams: 1 000849578.pdf: 926368 bytes, checksum: 028ef304931a5b9ae50cc9661f071f47 (MD5) / Eletroerosão é um processo não convencional de usinagem que se baseia na remoção de material por sucessivas descargas elétricas. Durante a descarga, as temperaturas podem atingir 12.000°C, seguidas de um rápido resfriamento, criando uma zona termicamente afetada na superfície da peça. Essa zona possui propriedades diferentes com relação ao material base como: dureza superior, composição microestrutural e ainda podem existir microtrincas que afetarão o desempenho da peça usinada. Este trabalho estudou a influência do tamanho de grão da peça usinada na integridade superficial resultante. Para os ensaios utilizou-se um aço baixo carbono comercialmente conhecido como COS AR 60 com tamanhos de grãos ferríticos distintos. Avaliou-se a integridade superficial a partir de um perfil de microdureza e imagens da microestrutura resultante. Também foi avaliada a formação de microtrincas, bem como suas espessuras. Verificou-se que a condição de desbaste resulta em camadas brancas de maiores espessuras e ainda que os materiais com grãos ultrafinos usinados sob mesma condição que aqueles com grãos convencionais apresentam camadas brancas menores. A microdureza é maior na camada branca quando comparada com as outras camadas. Os materiais com grãos ultrafinos apresentam uma transição de microdureza mais suave quando comparada a dos grãos convencionais, podendo... / Electrical Discharge Machining (EDM) is a non-conventional machining process which is based on material removal by successive electrical discharges. During each discharge temperatures can reach 12,000 °C, followed by rapid cooling, creating a heat-affected zone on the workpiece surface. This zone has different properties with respect to the base material (bulk) such as higher hardness, microstructural composition and may still exist microcracks that will affect the performance of the machined part. This research determined the influence of workpiece grain size on the machined surface integrity. Low carbon steel named commercially as COS AR 60 with different ferritic grain sizes was applied to machining tests. Surface integrity of the machined subsurface (white layer, heat- affected zone and bulk) was evaluated by considering microhardness gradient, microstructure composition and microcracks formation. The results show that the roughing condition increases the white layer but it is smaller for ultrafine-grained material. The hardness is highest in white layer when compared to other layers. The materials with ultrafine grains present a softer microhardness transition as compared with the conventional grains, which may improve the performance of the part in service from the standpoint of crack propagation

Made available in DSpace on 2016-01-13T13:27:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-23. Added 1 bitstream(s) on 2016-01-13T13:33:05Z : No. of bitstreams: 1 000846365.pdf: 1820557 bytes, checksum: 0eeb09d66410b8f2dc302cd63e42175d (MD5) / O Business Process Management (BPM) é considerado por alguns autores um dos temas mais atuais na era da informação, pois, de um lado, ele aborda a interação de pessoas e organizações e, de outro, softwares de reconhecimento de processos. O BPM une gestão de negócio e tecnologia da informação promovendo a interação e melhoria dos processos de negócio das organizações ao utilizar métodos, técnicas e ferramentas de modelagem, publicação, controle e análise de processos operacionais envolvendo pessoas e sistemas diversos. Neste trabalho é apresentada uma revisão bibliográfica sobre processos, processos de negócio, gestão de processos de negócio, gestão de processos de negócio em organizações públicas, estruturação e modelagem de processo, maturidade em processos de negócios e principais linguagens e ferramentas para modelagem de processos de negócio. O objetivo deste trabalho foi verificar como o BPM pode auxiliar na melhoria dos processos de uma Universidade Pública do Estado de São Paulo, além de identificar potenciais limitantes a entraves ao uso do BPM neste contexto. Para isso, foi realizada a comparação de algumas linguagens de modelagem de processos e de alguns softwares de modelagem de processos de modo a identificar as melhores ferramentas para o desenvolvimento deste trabalho. Após, procedeu-se com a aplicação do ciclo de gerenciamento de BPM, passando pelas etapas de planejamento, modelagem e otimização e implantação dos processos. Além dos benefícios da aplicação do BPM, como redução de tempo e custos de execução dos processos, o aumento do conhecimento, sobre o processo, a redução de burocracia para sua execução e automação dos processos através do desenvolvimento de um software de gerenciamento dos processos, foram encontradas limitações para sua implantação, como a estrutura organizacional de uma Universidade Pública, o número e a complexidade dos processos, o... / The business Process Management (BPM) is one of the current issues in the information age, because on the one hand, it addresses the interaction of people and organizations and on the other, recognition software processes. BPM unites business management of organizations to use methods, techniques and modeling tools, publication, control and analysis of business processes involving people and different systems. This work presents a literature review of processes, business processes, management of business processes, management of business processes, management of business processes in public organizations, structuring and process modeling, business process maturity and the major languages and tools for modeling business processes in order to see how BPM can help improve the processes of a Public University of São Paulo State, in addition to identifying and limiting potential barriers to the use of BPM in this context. For this, the comparision of some languages of process modeling and some modeling software processes to identify the best tools for the development modeling and some modeling software processes to identify the best tools for the develpment of this work was performed. After, we proceeded with the implementation of the BPM lifecycle management, through the stages of planning, modeling and optimization and implementation of processes. Besides the benefits of application of BPM, such as reduced time and processes running costs, increased knowledge about the process, bureaucracy reduction for its implementation and automation of processes through the development of a management software processes were found limitations for its implementation, such as the organizational structure of a public university, the number and complexity of cases, the level of maturity in which the proceedings are, cultural issues and resource constraints for acquisition of suitable tools for deploying BPM

Made available in DSpace on 2014-11-10T11:09:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-24Bitstream added on 2014-11-10T11:58:02Z : No. of bitstreams: 1 000792618.pdf: 5045868 bytes, checksum: 0fae4b357928f426a16db7cd767b57fd (MD5) / Neste estudo foi avaliada a influência dos parâmetros físicos (rigidez do cutelo, comprimento do corpo de prova, geometria do cutelo) sobre a magnitude das interferências presentes nas curvas força vs tempo e força vs deslocamento, também foi estudado o efeito de diversos filtros sobre o sinal coletado. Foram empregados cutelos instrumentados (atuando como células de carga) de diferente rigidez e também um cutelo com geometria distinta em relação aos demais. Foram realizados ensaios com corpos de prova de comprimento iguais a 55m (em conformidade com a ASTM E-23), 70 mm e 85 mm. Os dados foram tratados com filtros digitais: passa-baixa, passa-alta, passa-faixa e média móvel, os espectros dos sinais filtrados foram comparados aos dos sinais originais. Os resultados indicaram que a rigidez do cutelo possui relação inversa com a magnitude das interferências, por outro lado o comprimento do corpo de prova possui relação direta com o aumento no nível de interferências, o cutelo com geometria diferenciada também exerceu influência sobre a curva força vs deslocamento. A média móvel mostrou-se promissor no tratamento dos dados, desde que seja utilizado um número reduzido de pontos, de modo a não eliminar componentes fundamentais do sinal de interesse. Para os casos analisados o espectro do sinal encontra-se entre 100 Hz e 50 kHz, no entanto a faixa entre 10 kHz e 50 kHz há predomínio das componentes responsáveis pelas interferências. / In this work, was the influence of physical parameters evaluated (stiffness of the striker, length of the specimen, the geometry of the striker) on the magnitude of the interference present in the curves load vs. time and load vs. displacement, the effect of various filters on the signal obtained was also studied. In this study, instrumented strikers (like load cells) of different stiffness and were used a striker which has a different geometry than the others was also tested. Furthermore, the tests were conducted with specimens with length equal to 55 mm (according with ASTM E-23), 70 mm and 85 mm. The data were processed by these digital filters: low pass, high pass, band pass and moving average. The spectrums of the filtered signals were compared with the original ones. The results showed that the stiffness of the striker has an inverse relation with the magnitude of the interference. On the other hand, the length of the specimen has a direct relation with the increased level of interference, the striker with different geometry also exerted influence on the load vs displacement curve. The moving average filter has been a good way out in the treatment of data, but is necessary to use a limited number of points in order not to eliminate essential components of the signal which contains information about the deformation and fracture process. For the materials used in this work, the signal spectrum is between 100 Hz and 50 kHz, but the range between 10 kHz and 50 kHz is predominantly responsible for the interference components.

A partir dos estudos realizados por Shingo (1996), Ohno (1997), e Womack e Jones (1998), este estudo buscou identificar quais os elementos que interferem no desempenho da manufatura enxuta da empresa Ognibene, nas unidades do Brasil e da Itália, na visão dos funcionários e dos gestores. A partir deste objetivo, buscou-se relacionar os elementos da manufatura enxuta, seu grau de importância, o grau de entendimento dos gestores e funcionários quanto aos cinco princípios fundamentais da produção enxuta, e realizar proposições para complementar sua atual aplicação. A metodologia da pesquisa aplicada para o alcance dos objetivos foi a pesquisa quantitativa descritiva, com caráter exploratório, operacionalizada através de um estudo de caso. Os resultados obtidos evidenciam a identificação dos elementos da manufatura enxuta aplicados na empresa Ognibene, e as conclusões demonstram que os objetivos deste estudo foram atingidos, contribuindo para uma melhor compreensão da manufatura enxuta e dos ganhos que podem ser o btidos com sua aplicação. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-08-06T18:29:07Z No. of bitstreams: 1 Dissertacao Evandro Lazzarotto.pdf: 2542061 bytes, checksum: 819a59c2c337199f36eb17e6b16cbf4c (MD5) / Made available in DSpace on 2015-08-06T18:29:07Z (GMT). No. of bitstreams: 1 Dissertacao Evandro Lazzarotto.pdf: 2542061 bytes, checksum: 819a59c2c337199f36eb17e6b16cbf4c (MD5) / From the studies performed by Shingo (1996), Ohno (1997), and Womack & Jones (1998), this essay aimed to identify the factors that influence the performance of the lean manufacturing at Ognibene Company, in the view of its employees and management staff, in the Brazilian and Italian locations. Based on this target, this study tried to relate the elements of lean manufacturing, its importance level, the understanding level of managers and employees about the five principles of lean manufacturing, and make proposals to complement its current application. To achieve the objectives, this research applied the descriptive quantitative methodology, with exploratory character, operationalized through a case study. The obtained results show the identification of the lean manufacturing elements applied at Ognibene Company, and the conclusion demonstrates that the objectives of this essay were achieved, contributing for a better comprehension of the lean manufacturing and the gains that can be acquired with its application.

Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2018. / Industrial processes tend to have very complex mathematical models that in most instances result in very model specific optimal estimation and designs of control strategies. Such models have many composition components, energy compartments and energy inventories that result in many process variables that are intertwined and too complex to separate from one another. Most of the derived mathematical process models, based on the application of first principles, are nonlinear and incorporate unknown parameters and unmeasurable states. This fact results in difficulties in design and implementation of controllers for a majority of industrial processes. There is a need for the existing parameter and state estimation methods to be further developed and for new methods to be developed in order to simplify the process of parameters or states calculation and be applicable for real-time implementation of various controllers for nonlinear systems. The thesis describes the research work done on developing new parameter and state estimation methods and algorithms for bilinear and nonlinear processes. Continuous countercurrent ion exchange (CCIX) process for desalination of water is considered as a case study of a process that can be modelled as a bilinear system with affine parameters or as purely nonlinear system. Many models of industrial processes can be presented in such a way. The ion exchange process model is developed based on the mass balance principle as a state space bilinear model according to the state and control variables. The developed model is restructured according to its parameters in order to formulate two types of parameter estimation problem – with process models linear and nonlinear according to the parameters. The two models developed are a bilinear model with affine and a nonlinear according to the parameters model. Four different methods are proposed for the first case: gradient-based optimization method that uses the process output measurements, optimization gradient based method that uses the full state vector measurements, direct solution using the state vector measurements, and Lagrange’s optimization technique. Two methods are proposed for the second case: direct solution of the model equation using MATLAB software and Lagrange’s optimisation techniques. / National Research Foundation (NRF)

Orientador: Ruis Camargo Tokimatsu / Banca: Adyles Arato Junior / Banca: Maria Cristina Adami Gatti / Resumo: Neste estudo foi avaliada a influência dos parâmetros físicos (rigidez do cutelo, comprimento do corpo de prova, geometria do cutelo) sobre a magnitude das interferências presentes nas curvas força vs tempo e força vs deslocamento, também foi estudado o efeito de diversos filtros sobre o sinal coletado. Foram empregados cutelos instrumentados (atuando como células de carga) de diferente rigidez e também um cutelo com geometria distinta em relação aos demais. Foram realizados ensaios com corpos de prova de comprimento iguais a 55m (em conformidade com a ASTM E-23), 70 mm e 85 mm. Os dados foram tratados com filtros digitais: passa-baixa, passa-alta, passa-faixa e média móvel, os espectros dos sinais filtrados foram comparados aos dos sinais originais. Os resultados indicaram que a rigidez do cutelo possui relação inversa com a magnitude das interferências, por outro lado o comprimento do corpo de prova possui relação direta com o aumento no nível de interferências, o cutelo com geometria diferenciada também exerceu influência sobre a curva força vs deslocamento. A média móvel mostrou-se promissor no tratamento dos dados, desde que seja utilizado um número reduzido de pontos, de modo a não eliminar componentes fundamentais do sinal de interesse. Para os casos analisados o espectro do sinal encontra-se entre 100 Hz e 50 kHz, no entanto a faixa entre 10 kHz e 50 kHz há predomínio das componentes responsáveis pelas interferências. / Abstract: In this work, was the influence of physical parameters evaluated (stiffness of the striker, length of the specimen, the geometry of the striker) on the magnitude of the interference present in the curves load vs. time and load vs. displacement, the effect of various filters on the signal obtained was also studied. In this study, instrumented strikers (like load cells) of different stiffness and were used a striker which has a different geometry than the others was also tested. Furthermore, the tests were conducted with specimens with length equal to 55 mm (according with ASTM E-23), 70 mm and 85 mm. The data were processed by these digital filters: low pass, high pass, band pass and moving average. The spectrums of the filtered signals were compared with the original ones. The results showed that the stiffness of the striker has an inverse relation with the magnitude of the interference. On the other hand, the length of the specimen has a direct relation with the increased level of interference, the striker with different geometry also exerted influence on the load vs displacement curve. The moving average filter has been a good way out in the treatment of data, but is necessary to use a limited number of points in order not to eliminate essential components of the signal which contains information about the deformation and fracture process. For the materials used in this work, the signal spectrum is between 100 Hz and 50 kHz, but the range between 10 kHz and 50 kHz is predominantly responsible for the interference components. / Mestre

A partir dos estudos realizados por Shingo (1996), Ohno (1997), e Womack e Jones (1998), este estudo buscou identificar quais os elementos que interferem no desempenho da manufatura enxuta da empresa Ognibene, nas unidades do Brasil e da Itália, na visão dos funcionários e dos gestores. A partir deste objetivo, buscou-se relacionar os elementos da manufatura enxuta, seu grau de importância, o grau de entendimento dos gestores e funcionários quanto aos cinco princípios fundamentais da produção enxuta, e realizar proposições para complementar sua atual aplicação. A metodologia da pesquisa aplicada para o alcance dos objetivos foi a pesquisa quantitativa descritiva, com caráter exploratório, operacionalizada através de um estudo de caso. Os resultados obtidos evidenciam a identificação dos elementos da manufatura enxuta aplicados na empresa Ognibene, e as conclusões demonstram que os objetivos deste estudo foram atingidos, contribuindo para uma melhor compreensão da manufatura enxuta e dos ganhos que podem ser o btidos com sua aplicação. / From the studies performed by Shingo (1996), Ohno (1997), and Womack & Jones (1998), this essay aimed to identify the factors that influence the performance of the lean manufacturing at Ognibene Company, in the view of its employees and management staff, in the Brazilian and Italian locations. Based on this target, this study tried to relate the elements of lean manufacturing, its importance level, the understanding level of managers and employees about the five principles of lean manufacturing, and make proposals to complement its current application. To achieve the objectives, this research applied the descriptive quantitative methodology, with exploratory character, operationalized through a case study. The obtained results show the identification of the lean manufacturing elements applied at Ognibene Company, and the conclusion demonstrates that the objectives of this essay were achieved, contributing for a better comprehension of the lean manufacturing and the gains that can be acquired with its application.

Neste trabalho, é apresentada uma metodologia para fabricação de transistores de filmes finos orgânicos sobre substratos flexíveis e resultados de simples testes de flexão desses substratos. Foram fabricados transistores de Poli(3-hexiltiofeno) (P3HT) com diversas arquiteturas não se preocupando somente com a relação W/L dessas, mas também com a facilidade de caracterizar os dispositivos em superfícies curvas. Os transistores foram fabricados sobre diversos substratos como silício, vidro e PET, para que fosse possível uma comparação de eficiência entre eles. A mobilidade do P3HT se manteve próximo de 10-2 cm2/Vs enquanto que a corrente de ION apresentou um aumento significativo, Os transistores sobre PET se mostraram resistentes à flexão, suportando raios de curvaturas de até 0,8 cm sem afetar sua resposta. Porém foi identificado que a compressão ou a tração resultam em efeitos diferentes nos transistores, principalmente sobre os eletrodos de ouro. / Presented herein is a fabrication procedure for organic thin film transistors over flexible substrates. It is also shown the results of the bending tests on these devices. Transistors of poly(3-hexyl thiophene) (P3HT), with different architectures were fabricated, aiming not only the W/L relation but also, the capability contacting bent electrodes for testes on curved surfaces. The transistors were fabricated over rigid and flexible substrates like silicon, glass and PET, allowing the efficiency comparison between them. The P3HT mobility was kept stable, around 10-2 cm2/Vs, while the ION current presented a significant change on different substrates. The transistors over PET showed to be resistance to bending, being able to bend to a curve radius of 0.8 cm without losing its transistor characteristics. Although, it was identified that the direction of bending, compression and traction, result on different effects over the transistors, especially over the golden electrodes.

M.Tech. (Operations Management) / The research is about the application of lean manufacturing tool known as manufacturing kaizen in order to improve a work process at . The company is based in Kempton Park, South Africa, used as a case study to evaluate the benefit of manufacturing kaizen at a specific industrial concern. The research demonstrated how manufacturing kaizen when used appropriately can help APSAP PTY LTD to eliminate waste, have better inventory control, short process cycle times, and better overall financial and operational procedures. The goal was to reduce the identified waste using manufacturing kaizen tool. Waste reduction eventually reduced the cycle time of the work process. The primary objective of the thesis was to study and analyze the cylinder preparation process in APSAP PTY LTD. The process activities were captured, then analyzed using the process map. The secondary objective was to identify waste in the process. Major businesses in South Africa have been trying to adopt new business initiatives in order to stay competitive. One way to increase this is to apply proper manufacturing strategy and use of lean manufacturing or continuous improvement tools to achieve business objective which is to stay competitive and to increase profit. The research addresses the application of a lean manufacturing tool called manufacturing kaizen. Manufacturing kaizen refers to a technique used for improving a work process by the eliminating waste within that process in the organization. It is one of the improvement tools that focus on cost reduction by eliminating non-value added activities. Kaizen achieves the elimination of waste by empowering people with tools and a process to uncover improvement opportunities and make change. Participants are key aspect in implementing the manufacturing kaizen event, since they are the people directly involved. Identifying the key people that will be used in the manufacturing kaizen event is very crucial for the success of the event. Any changes or improvements of the process will have direct impact to the people. It is important that people who are directly affected by change become part of the process and feel empowered. Kaizen understands waste to be any activity that is not value adding from the perspective of the customer. The research unpacks manufacturing Kaizen and looks into its qualitative nature and its application within a working environment and how it influence productivity. It also investigates how this tool can be applied in a process or chemical industry and the benefits it can provide to an organization. The initial step in the approach was to outline data collected and examining techniques used to collect the data. The researcher carried out direct observation as he was physically present, and personally monitored what was taking place. The results show that labor productivity can be improved over time after the introduction of manufacturing kaizen. It concludes that with the introduction of manufacturing kaizen, transformation at workplace can be established leading to productivity improvement within an organization. The research has shown that with the proper use of manufacturing kaizen , waste reduction can be achieved.

Electrical Discharge Machining (EDM) is a non-contact manufacturing process in which material is removed from a metal workpiece by high frequency electrical pulses produced between an electrode and the workpiece. EDM machines are usually stand-alone devices, and are quite expensive. The objective of this research was to integrate an EDM machine and an existing reconfigurable CNC machine tool, using a modular approach, to enable conventional milling and EDM to be conducted in a co-ordinated fashion on the same machine tool.