This master thesis consider the proposal for quality improvement of an industrial process. There are recomended proposals and methods for improvement of current situation of processing on the production of provided information here.

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The organisation of maintenance, in the Aseptic Liquid Food (ALF) industry, represents an important management task that enables a company to pursue higher manufacturing effectiveness and improved market share. This research is concerned with the process to design and implement maintenance tasks. These two complementary processes (design and implementation) have been thought and designed to answer the particular needs of food industry regarding product safety and equipment reliability. Numerous maintenance engineering researchers have focused on maintenance engineering and reliability techniques highlighting the contribution of maintenance in achieving world class manufacturing and competitive advantage. Their outcome emphasizes that maintenance is not a “necessary evil” because of costs associated, but it can be considered an “investment” that produces an added value which generates a real company profit. The existing maintenance engineering techniques pursue equipment reliability at minimum cost; but in food industry, food safety represents the most critical issue to address and solve. The research methodology chosen is based on case studies coming from ALF industries. These show that low maintenance effectiveness could have dramatic effects on final consumers and on the company’s image and underline the need of a maintenance design and implementation process that takes into consideration all critical factors relevant to liquid food industry. The analysis of measurable indicators available, represents a tool necessary to show the status of critical performance indicators and reveals the urgency of a research necessary to address and solve the maintenance problems in food industry. The literature review underlines the increasing regulations in place in food industry and that no literature is available to define a maintenance design and implementation process for ALF and in general for food industry. The literature review enabled also the gap existing between theory and real maintenance status, in the ALF, to be identified and the aim of the research was to explore this gap. The analysis of case studies and Key Performance Indicators (KPI’s) available highlights the problem and the literature review provides the knowledge necessary to identify the process to design and implement maintenance procedures for ALF industry. The research findings provide a useful guide to identify the process to design maintenance tasks able to put under control food safety and equipment reliability issues. Company’s restraining forces and cultural inertia, that work against new maintenance procedures, have been analysed and a maintenance implementation process have been designed to avoid losing the benefits produced by the design phase. The analysis of condition monitoring systems shows devices and techniques useful to improve product safety, equipment reliability, and then maintenance effectiveness. This research aimed to fill the gap in the existing literature showing the solution to manage both food safety and production effectiveness issues in food industry. It identifies a maintenance design process able to capture all conceivable critical factors in food industry and to provide the solution to design reliable task lists. Furthermore, the maintenance implementation process shows the way to maximize the maintenance design outcome through the empowerment of equipment operators and close cooperation with maintenance and quality specialists. The new maintenance design and implementation process represents the answer to the research problem and a reliable solution that allows the food industry to improve food safety and production effectiveness.

In this thesis, a real world application of the constant work in process (Conwip) system in an electronics company is realized. The aim of the application is to reduce the work in process (WIP) inventory while maintaining the same throughput level. A model is developed to determine the constant work in process level of the Conwip system for the production lines in this company. The approximated mean value analysis approach is used for the solution. Real system data are collected before and after the Conwip application. Hypothesis tests are used to compare the WIP and the throughput levels of the Conwip system with the existing push control system for a pilot production line. Results of the hypothesis tests show that the Conwip production control system can signinifcantly reduce the WIP while maintaining the same throughput rate.

Fedmis Pty (Ltd) situated in Palaborwa, South Africa produces phosphoric acid using the wet process production process. For this study, two main areas of concern in the wet process phosphoric acid production were investigated. The first area is the formation of sludge in the system due to impurities that reduces the grade of the acid produced, thereby lowering the selling price. The second area is the crystallisation of the gypsum that influences filtration and thereby affects plant productivity. These two aspects were investigated separately as they occur in different steps of the production process at different acid concentrations. A major component of the acid sludge is known as x-compound, ((Fe,Al)3KH)14 (PO4)8.4H2O). The purpose of the investigation of x-compound is to determine what effects different ionic impurities have on its precipitation and to determine if these effects could be used to decrease the amount of sludge formation. Due to the complexity of the system and the wide variety of impurities only the major impurities were considered in this study. These impurities included potassium (K+), sodium (Na+), magnesium (Mg2+), aluminium (Al3+) and iron (Fe3+). For all the experiments investigating the effect of impurities, analytical reagents were used on laboratory scale. For the silica experiments, commercially available samples were used. For the experiments investigating the impurity effects on the precipitation of x-compound it was found that: <ul> <li> Agitation increases x-compound precipitation and can be used commercially to increase the precipitation rate to a point where sludge can be removed before transportation.</li> <li> Adding x-compound seeding crystals or magnesium ions also increases precipitation.</li> <li> Adding gypsum, sodium, hexafluorosilicates or fluorosilic acid reduces the precipitation, with sodium ions producing the lowest yield. This reduction is however not sufficient to be used commercially.</li> </ul> From the Raman study it became clear why x-compound precipitation is such a slow process. E At low acid concentrations, more H2PO4 - ions are present that form a complex with iron and aluminium. E As the acid concentration increases the concentration of H2PO4- ions decrease as the degree of dissociation of phosphoric acid decreases. The ferric- H2PO4- and aluminium- H2PO4- complexes become less stable and ultimately precipitation of the x-compound is favoured above solvation. E Addition of potassium impurities to the solutions had no visible effect on the Raman spectra and is suspected not to form a complex with the acid. From the silica sources investigated namely Dicalite, Serina Kaolin, Foskor silica and Aerosil 200 it can be concluded that none of the sources will be useful for the removal of potassium through formation of potassium hexafluorosilicates. For the determination of the concentration of impurities present in the production of phosphoric acid, the Fedmis monitoring program was initiated. It included the monitoring of Foskor rock analyses on a daily basis, and the monitoring of the 27%, 39% and 54% P2O5 phosphoric acid and precipitate, from these acid solutions on a weekly basis. From the investigation of the effect of these impurities on the solubility of potassium hexafluorosilicates, it was found that magnesium causes K2SiF6 to be the most soluble and fluoride the least. Unfortunately, the impurities did not help to reduce the potassium concentrations in the acid to below the required amount for sludge formation. For the calcium sulphate dihydrate surfactant experiments, the purpose of the investigation was to determine whether higher crystallisation qualities could be obtained to improve plant productivity. The investigation was limited to using surfactants with sulphate or phosphate functionalities and experiments were done on laboratory scale using analytical reagents. Atphos E3205, Atpol E3202 and Atpol E1231 are polyethoxylated alkyl phenol phosphate esters that had no visible effect on the crystal structure of the precipitated gypsum, but differences in the crystal sizes were observed. Smaller crystal structures with relatively equal masses compared to reference experiments are an indication of a growth inhibitor and a nucleation promoter as seen with Atphos E3205 and Atpol E3202. Increased crystal sizes were obtained using Atpol E1231. The use of Calsoline Oil caused a wider crystal size distribution in the precipitated crystals as thin and broad crystals with approximately the same length are found. The crystal mass obtained is also approximately the same as that of the reference experiment. Thus, it can be concluded that the surfactant affects the growth of the crystals and not the nucleation. Arlatone 1489, calcium gluconate monohydrate, Dowfax Hydrotrope and Tamol NN 8906 had no visible effect on the structure or size of the precipitated gypsum crystals. With the use of Nansa SS30, drastic effects were seen on the crystallisation of the calcium sulphate as small hexagonal rods were found. With an increase in surfactant concentration, there is a clear decrease in the mass of crystals obtained as well as crystal size. An increase in the crystal size distribution and a decrease in crystal size reduced the filtration rate dramatically. Experiments carried out for 24 hours exhibited the same trends where there is a decrease in yield with an increase in surfactant concentration. Higher yields were however obtained proving that mass transfer barriers were overcome. The results from these experiments again indicate that the surfactant affects crystal growth and nucleation. With the use of Dowfax 3B2 there is definite reduction in yield with an increase in surfactant concentration reaching a minimum at approximately 70% yield. Due to the presence of large amounts of smaller crystals and the almost constant yield obtained compared to the reference experiment, it can be concluded that this surfactant is a growth and not a nucleation inhibitor. As with Nansa SS30, experiments where Empicol LZ/D was used show a continuous decrease in the yield obtained with an increase in the surfactant concentration. At higher concentration of Empicol LZ/D, it seems as if this surfactant changed from a growth promoter to a growth inhibitor because although broad longer crystals are present, there are now also much smaller crystals formed. The crystal size distribution also broadens considerably. Overall, very high yields were obtained using Empimin KSN70 and the observed crystal size distributions were very narrow. The only difference was that the crystals appeared to be more porous or fibrous compared to the reference experiment. It is recommended that the experiments showing promise as crystal habit modifiers like Nansa SS30 and Empicol LZ/D be investigated in more detail as well as combinations of surfactants. Both the areas of concern in the process were investigated successfully. For the sludge formation problem, it is now clear what effects the precipitation of x-compound as well as what affect the impurities and operating conditions have. For the crystallisation of gypsum using surfactants, it was proven that surfactants could be used to affect crystal growth, shape and distribution and in this way influence filtration. / Dissertation (MSc(Chemical Engineering))--University of Pretoria, 2005. / Chemical Engineering / unrestricted

The present thesis is concerned with production process management in a small innovative and developing Czech company. The introductory part describes a selected product from both a functional point of view and a constructional point of view. The theoretical part of the thesis is followed by a section which analyzes the initial state of production process of the product. The next part comes with ideas for new approaches to production process management, respecting available company resources, which are necessary for their implementing. The final part of the thesis provides a summary of implemented solutions and solutions that the management of the company plans to implement.

A tese tem por objetivo investigar como se forma o juízo sobre os fatos na decisão judicial. Parte-se do pressuposto de que um juízo verdadeiro sobre os fatos é condição necessária, ainda que não suficiente por si só, para a justiça da decisão. A estratégia adotada é estudar o processo de conhecimento ao longo do qual se forma o juízo sobre os fatos. Inicia-se a exposição afirmando-se que são objeto de julgamento, e, portanto, do processo de conhecimento, ações humanas, as quais são sempre singulares, irrepetíveis e praticadas no passado. Sustenta-se que as ações só podem ser apreendidas adequadamente quando se consideram todos os aspectos que a caracterizam, a saber: que a ação tem como causa um agente, que é praticada com base em motivos e com determinada intenção e que é praticada em circunstâncias que, em sua totalidade, só dizem respeito a cada ação particular. Definido o objeto, passa-se ao primeiro aspecto relativo ao sujeito do conhecimento: a análise da repercussão dos dois tipos clássicos de raciocínio decisório judicial sobre a apreensão das ações particulares do caso. Conclui-se que o raciocínio analógico favorece uma apreensão das ações ampliada em relação ao raciocínio subsuntivo. O raciocínio subsuntivo, por sua vez, inibe, mas não é incompatível, com essa apreensão ampla. O trabalho retorna ao objeto de conhecimento, desta feita para analisar o que se oferece ao conhecimento do juiz para obter informações sobre as ações humanas que serão julgadas. Conclui-se que esses elementos ou são evidências, sobre as quais o juiz realiza inferências, ou presunções, que ele aplica. Evidências e presunções contribuem de forma variada para a satisfação de critérios de verdade. A tese se encerra com um retorno ao sujeito do conhecimento judicial: a análise dos dois modos de ajuizar as informações obtidas mediante inferências obtidas das evidências e os resultados das aplicações de presunções. Pelo método de resposta a questões feitas com base na regra de Direito que se supõe aplicável é possível resolver o caso nos termos dessa mesma regra de Direito, mas com um possível déficit de verdade, pois ficam de fora do juízo os aspectos das ações não contemplados pelas questões formuladas. Pelo método narrativo, os fatos são expostos em toda sua amplitude, o que atende mais satisfatoriamente à pretensão de verdade que lhe é inerente. O método narrativo não é incompatível com o método de questões, mas o completa e serve de teste à verdade das respostas. / The thesis aims to investigate how the judges opinion about the facts is built. Its basic assumption is that a true statement of the facts is a necessary condition to the justice of the decision, although insufficient by itself. The strategy adopted is to study the process of knowledge production which ends with the ascertainment of the facts. The study begins by saying that the object of trial, and therefore of the process of knowledge, are human actions, which are always unique, unrepeatable and practiced in the past. It is argued that actions can only be grasped properly when you consider all the aspects that characterize them, namely that the action is caused by an agent, it is practiced on the basis of reasons, with specific intention and that is practiced in circumstances that, in its entirety, only relate to each particular action. Set the object we pass to the first aspect of the subject of knowledge: the analysis of the impact of the two classical types of judicial reasoning on the task of knowing the particular actions of the case. It is concluded that analogical reasoning favours an expanded understanding of actions in relation to subsumption reasoning. Subsumption reasoning, in turn, inhibits, but is not inconsistent with, a broad approach to the facts. The work returns to the object of knowledge, this time to analyze what is offered to the attention of the judge to give him information about human actions that will be judged. We conclude that these elements are either evidence on which the judge makes inferences or presumptions that he applies. Evidence and presumptions contribute in different ways to the satisfaction of criteria of truth. The thesis concludes with a return to the subject of legal knowledge: the analysis of the two ways of ascertaining the information obtained through the inferences made on the basis of evidences and by application of presumptions. By the method of answering questions based on the rule of law that is supposed to apply it is possible to solve the case under that same rule of law, but with a possible deficit of truth, for the court doesnt take into account any information that is not an answer to the questions formulated. By the narrative method, the facts are exposed in all their diversity, which serves more satisfactorily to the claim to truth that must guide the judge. Moreover, the narrative method is not inconsistent with the method of questions, but functions as a complement and to test the truth of the answers.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / With the increase of the customer's demand degree, the search for the quality improvement is consolidated as one of the strategies more proceeded in the different market segments. The Six Sigma initiative is a system of quality management that has been showing efficient and effective in guide organizations in the way of improvement, taking the quality as fundamental reference. Related to the Six Sigma initiative, the problem of ascending research of this dissertation it was summed up: how to control in an objective way the performance Six Sigma in processes of continuous production? In a way, the objective of this dissertation is to develop, in the Six Sigma context, an objective model of performance control in processes of continuous production. The used research procedures were, with base in the objectives, the exploratory research and, with base in the technical procedures, the bibliographical research, the research of case study type and the experimental research. For fund the dissertation, was proceeded with the materialization of a theoretical reference on models of performance control and on the Six Sigma initiative, being identified in the sequence, in three organizations, two peculiarities of the processes of continuous production: the importance of the performance control in processes of continuous production, and the care exercised with the expedition of products doesn't conform. A model of Six Sigma performance control in processes of continuous production was proposed, model that contemplated the use of two performance indicators that were denominated sigma level and loss level. The model was positively evaluated, because the results demonstrated that the model of performance control presents characteristics capable to bring more objectivity in the performance control in processes of continuous production, because when different weights are attributed at the indicators of acting sigma level and loss level, different objective orientations of the model are had. In this way, the proposition and the evaluation of the model of Six Sigma performance control in processes of continuous production offered a larger understanding concerning the thematic proposal; besides showing the importance of models that they allow the control of capable managerial actions they increase the customers' satisfaction: fact that interferes in the profit and survival of the organizations. / Com o aumento do grau de exigência do cliente, a busca pela melhoria da qualidade está se consolidado como uma das estratégias mais seguidas nos diferentes segmentos de mercado. A iniciativa Seis Sigma é um sistema de gestão da qualidade que tem se mostrado eficiente e eficaz em nortear organizações no caminho da melhoria, tomando a qualidade como referência fundamental. Relacionada à iniciativa Seis Sigma concretizou-se o problema de pesquisa ascendente desta dissertação: como controlar de maneira objetiva o desempenho Seis Sigma em processos de produção contínua? De tal modo, o objetivo desta dissertação é desenvolver, no contexto do Seis Sigma, um modelo objetivo de controle do desempenho em processos de produção contínua. Os procedimentos de pesquisa utilizados foram, com base nos objetivos, a pesquisa exploratória e, com base nos procedimentos técnicos, a pesquisa bibliográfica, a pesquisa do tipo estudo de caso e a pesquisa experimental. Para alicerçar a dissertação, procedeu-se com a concretização de um referencial teórico sobre modelos de controle de desempenho e sobre a iniciativa Seis Sigma, sendo identificadas na seqüência, em três organizações, duas peculiaridades dos processos de produção contínua: a importância do controle do desempenho em processos de produção contínua, e o cuidado exercido com a expedição de produtos não conformes. Propôs-se então um modelo de controle do desempenho Seis Sigma em processos de produção contínua, modelo que contemplou a utilização de dois indicadores de desempenho que foram denominados nível sigma e nível de perda. Avaliou-se positivamente o modelo, pois os resultados demonstraram que o modelo de controle do desempenho apresenta características capazes de trazer mais objetividade no controle do desempenho em processos de produção contínua, pois quando diferentes pesos são atribuídos aos indicadores de desempenho nível sigma e nível de perda, têm-se diferentes orientações objetivas do modelo. Deste modo, a proposição e a avaliação do modelo de controle do desempenho Seis Sigma em processos de produção contínua ofereceram um maior entendimento acerca da temática proposta, além de mostrar a importância de modelos que permitam o controle de ações gerenciais capazes de aumentar a satisfação dos clientes: fato que interfere na lucratividade e sobrevivência das organizações.

A tese tem por objetivo investigar como se forma o juízo sobre os fatos na decisão judicial. Parte-se do pressuposto de que um juízo verdadeiro sobre os fatos é condição necessária, ainda que não suficiente por si só, para a justiça da decisão. A estratégia adotada é estudar o processo de conhecimento ao longo do qual se forma o juízo sobre os fatos. Inicia-se a exposição afirmando-se que são objeto de julgamento, e, portanto, do processo de conhecimento, ações humanas, as quais são sempre singulares, irrepetíveis e praticadas no passado. Sustenta-se que as ações só podem ser apreendidas adequadamente quando se consideram todos os aspectos que a caracterizam, a saber: que a ação tem como causa um agente, que é praticada com base em motivos e com determinada intenção e que é praticada em circunstâncias que, em sua totalidade, só dizem respeito a cada ação particular. Definido o objeto, passa-se ao primeiro aspecto relativo ao sujeito do conhecimento: a análise da repercussão dos dois tipos clássicos de raciocínio decisório judicial sobre a apreensão das ações particulares do caso. Conclui-se que o raciocínio analógico favorece uma apreensão das ações ampliada em relação ao raciocínio subsuntivo. O raciocínio subsuntivo, por sua vez, inibe, mas não é incompatível, com essa apreensão ampla. O trabalho retorna ao objeto de conhecimento, desta feita para analisar o que se oferece ao conhecimento do juiz para obter informações sobre as ações humanas que serão julgadas. Conclui-se que esses elementos ou são evidências, sobre as quais o juiz realiza inferências, ou presunções, que ele aplica. Evidências e presunções contribuem de forma variada para a satisfação de critérios de verdade. A tese se encerra com um retorno ao sujeito do conhecimento judicial: a análise dos dois modos de ajuizar as informações obtidas mediante inferências obtidas das evidências e os resultados das aplicações de presunções. Pelo método de resposta a questões feitas com base na regra de Direito que se supõe aplicável é possível resolver o caso nos termos dessa mesma regra de Direito, mas com um possível déficit de verdade, pois ficam de fora do juízo os aspectos das ações não contemplados pelas questões formuladas. Pelo método narrativo, os fatos são expostos em toda sua amplitude, o que atende mais satisfatoriamente à pretensão de verdade que lhe é inerente. O método narrativo não é incompatível com o método de questões, mas o completa e serve de teste à verdade das respostas. / The thesis aims to investigate how the judges opinion about the facts is built. Its basic assumption is that a true statement of the facts is a necessary condition to the justice of the decision, although insufficient by itself. The strategy adopted is to study the process of knowledge production which ends with the ascertainment of the facts. The study begins by saying that the object of trial, and therefore of the process of knowledge, are human actions, which are always unique, unrepeatable and practiced in the past. It is argued that actions can only be grasped properly when you consider all the aspects that characterize them, namely that the action is caused by an agent, it is practiced on the basis of reasons, with specific intention and that is practiced in circumstances that, in its entirety, only relate to each particular action. Set the object we pass to the first aspect of the subject of knowledge: the analysis of the impact of the two classical types of judicial reasoning on the task of knowing the particular actions of the case. It is concluded that analogical reasoning favours an expanded understanding of actions in relation to subsumption reasoning. Subsumption reasoning, in turn, inhibits, but is not inconsistent with, a broad approach to the facts. The work returns to the object of knowledge, this time to analyze what is offered to the attention of the judge to give him information about human actions that will be judged. We conclude that these elements are either evidence on which the judge makes inferences or presumptions that he applies. Evidence and presumptions contribute in different ways to the satisfaction of criteria of truth. The thesis concludes with a return to the subject of legal knowledge: the analysis of the two ways of ascertaining the information obtained through the inferences made on the basis of evidences and by application of presumptions. By the method of answering questions based on the rule of law that is supposed to apply it is possible to solve the case under that same rule of law, but with a possible deficit of truth, for the court doesnt take into account any information that is not an answer to the questions formulated. By the narrative method, the facts are exposed in all their diversity, which serves more satisfactorily to the claim to truth that must guide the judge. Moreover, the narrative method is not inconsistent with the method of questions, but functions as a complement and to test the truth of the answers.

This paper deals with the problem of optimization of a production plan by using genetic algorithms. It contains a brief overview of the principles behind genetic algorithms in scope of evolutionary algorithms and artificial intelligence in general. It also takes a closer look on the challenge of production planning and control and all activities connected to it. This is followed by description of the modification of genetic algorithms that needed to be done in order to implement it into a computer program, which is used to create and optimize the production plan, and is a result to the issue that this paper deals with. Incorporated is detailed escription of principles and functions of the program, that it offers to its users.