Modelagem e otimização por metodologia de superfícies de resposta: um estudo em arames de aço SAE 9254 para molas automobilísticas

Pós-graduação em Engenharia Mecânica - FEG

Estudo de caso de controle estatístico de processo: levantamento estatístico de defeitos em molduras

This graduate work approaches the study of Statistical Process Control - SPC, in a stage production of an industrial frame, aiming to use the tool of statistical process control (SPC) to assess the process capability. Where the process needs improvement as well not meet the specifications. Assessing the needs that the company needs to improve quality management, and the difficulties they present during the implementation of the CEP. The present study is to use the method of case study. The results are presented through study of the level of defects using Pareto diagrams and control chart by - (p) fraction defective, and checking the capacity and stability of the process using control charts and histograms XbarraR. The process demonstrated the need for improvements in process and quality management. At the end of the work are presented suggestions for improving the quality system of the company

Verificação da eficiência da metodologia Seis Sigma na redução da divergência de estoque em uma indústria de condutores de fluídos

This work was developed in order to reduce the discrepancy found between the stock data of an item in the system and the amount found physically in stock in the company presented on this study case. Therefore, this paper makes a study on system of information that can assist in the collection, control and manipulation of data regarding the company's stock. It is very important to do the inventory management, so we can control the level of this sub-product to meet sales orders and production. In the study discussed below, we used the Six Sigma methodology to identify points that had flaws in the process and thus improve their work where the results show grater process control and provide a reliable database to the point where no further problems of lack of components in stock

Estudo de caso de controle estatístico de processo: levantamento da variação de espessura de tábuas de pinus

This graduate work approaches the study of Statistical Process Control - SPC, in a stage production of an industrial frame, aiming to use the tool of statistical process control (SPC) to assess the process capability. Where the process needs improvement as well not meet the specifications. Assessing the needs that the company needs to improve quality management, and the difficulties they present during the implementation of the CEP. The present study is to use the method of case study. The results are presented through study, and checking the capacity and stability of the process using control charts XbarraR. The process demonstrated the need for improvements in process and quality management. At the end of the work are presented suggestions for improving the quality system of the company

Aplicação de princípios do pensamento enxuto no processo de envio e devolução de correspondências em um banco privado

The success obtained by the Toyota Company in implementing the Toyota Production System was a global case of study that generated different new approaches, such as Lean Thinking. This approach was already successfully applied to various sectors, breeding methodologies as Lean Service, Lean Office or Lean IT. In this paper, the main concepts of Lean Thinking were applied in an information flow through an action research, more specifically in the sending and return of mailing process from a bank. The objectives were to create changes that led to the decrease of the mail returning indexes and ultimately to cost reduction and waste elimination. For this purpose the actual situation was mapped, and after data collection and analysis, a future proposed state was generated for the information flow. Alongside, indicators were conceived for managing process control and a set of implemented and proposed improvements were delivered. The applied Lean Thinking concepts were considered efficient for the application, and the proposed objectives were achieved

Study of thermal decomposition of ignition temperature of bagasse, coal and their blends

In Brazil, due to its availability, sugar cane bagasse has a high potential for power generation. The knowledge of ignition behavior, as well as the knowledge of the chemical kinetics, in of fuels combustion process is important features in boilers projects and in the stability of the combustion process control. The aim of this study is to investigate the thermal behavior of sugar cane bagasse, coal and their blends. The methodology proposed by Tognotti et al. (1985) was applied to determine the ignition temperature for all samples. Ignition temperatures were 256oC for neat bagasse and 427oC for neat coal, and 275oC for both blends (50-50% and 25-75%). The ModelFree Kinetics was applied to determine the apparent activation energy (Eα) of the thermal decomposition of sugar cane bagasse. For the two major events of mass loss of bagasse which correspond to the thermal decomposition of organic matter (mainly hemicellulose, cellulose and lignin), average values of Eα were obtained for both combustion and pyrolysis processes. In synthetic air atmosphere, the Eα were 170.8±26.3 kJ⋅mol-1 and 277.8±58.6 kJ⋅mol-1, while in nitrogen atmosphere, the Eα were 185.0 ± 11.4 kJ⋅mol-1 and 82.1±44.4 kJ⋅mol-1. The results obtained can be explained by synergistic effects when both bagasse and coal were blended, changing the fuel reactivity.

Qualidade da semeadura direta de milho com dois mecanismos de pressão no disco sulcador sob duas velocidades

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Implantação do controle estatístico de processo: um estudo de caso em uma empresa do setor alimentício

Pós-graduação em Engenharia de Produção - FEB

Tempos, movimentos e qualidade da operação de colheita mecanizada de soja em função do formato de talhões

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Qualidade da semeadura e do arranquio mecanizado do amendoim

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Aplicação da análise de séries temporais para detecção e prognóstico de danos em estruturas inteligentes

Pós-graduação em Engenharia Mecânica - FEIS

Aplicação mecanizada de N-P-K individualizada na cultura da cana-de-açúcar

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Physicothermal properties of aqueous sodium chloride solutions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Joint X̄ and R charts with variable parameters

Recent studies have shown that the X̄chart with variable parameters (Vp X̄ chart) detects process shifts faster than the traditional X̄ chart. This article extends these studies for processes that are monitored by both, X̄ and R charts. Basically, the X̄ and R values establish if the control should or should not be relaxed. When the X̄ and R values fall in the central region the control is relaxed because one will wait more to take the next sample and/or the next sample will be smaller than usual. When the X̄ or R values fall in the warning region the control is tightened because one will wait less to take the next sample and the next sample will be larger than usual. The action limits are also made variable. This paper proposes to draw the action limits (for both charts) wider than usual, when the control is relaxed and narrower than usual when the control is tightened. The Vp feature improves the joint X̄ and R control chart performance in terms of the speed with which the process mean and/or variance shifts are detected. © 1998 IIE.

Efeito da microestrutura nas propriedades mecânicas de aços automotivos dissimilares soldados à laser

Pós-graduação em Engenharia Mecânica - FEG