Artigos
URI permanente para esta coleçãohttps://repositorio.fei.edu.br/handle/FEI/796
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Artigo de evento 0 Citação(ões) na Scopus The use of simulation as a tool to support decision-making in a piston manufacturing system(2013) Alexandre Augusto Massote; IGNACIO, B. A. F.The business scenario is characterized by a high complexity, which influences various aspects of the organizations, such as the decision-making. In this way, companies can use several techniques to reduce the risks and uncertainties of this process; among them is the computer simulation. Considering that, this article aims to demonstrate the effectiveness of this technique. In order to do so, it will simulate several situations of a piston manufacturing system linked with the expansion of the manufacturing cell. In summary, the method will be used as a support for the manager to decide which is the best option to expand the manufactory cell.Artigo 5 Citação(ões) na Scopus Electronic collaboration in supply chain management: a study of manufacturing companies in Brazil(2016-01-05) Claudia Mattos; LAURINDO, F. J. B.Electronic collaboration emerges as a differentiating element in supply chain management. This new operational method makes it necessary to understand which concepts are related to the collaborative context, which tools are used and what their impact on performance is, so that managers can direct their management chain decisions. The broad aim of this study is to examine the application of collaborative tools in the supply chain, and to check if managers identify performance improvements in the group of companies that apply these tools. The methodology is based on literature review and quantitative method, using the cluster analysis statistical technique. The results indicate that the group of companies with more significant collaborative features has a different perception of performance, when compared to other groups with lower level of collaborative tools implementation.- MRAS-based sensorless control for high-speed induction machine connected to the grid(2013-11-05) Fabio Lima; ROSA, F. C.; FUMAGALLI, M. A.This paper describes a MRAS-based sensorless control of a high-speed squirrel cage induction machine connected to the grid. This paper contributes with the subject when using a high-speed machine supported by active magnetic bearings (AMB) for energy applications. This kind of system is suitable for energy generation from gas sources. To control the grid side as well as the generator side a back-to-back converter with voltage oriented control (VOC) and rotor field oriented control (RFOC), respectively, is used. Simulations are presented for the MRAS observer, and some experimental results are also showed. A test bench was designed and the final experimental results are undergoing. © 2013 IEEE.
- Hybrid Method CONWIP/KANBAN: A case study Método híbrido CONWIP/KANBAN: Um estudo de caso(2011-01-05) SERENO, B.; DA SILVA, D. S. A.; DA SILVA, D. S. A.; Mauro SampaioKANBAN. CONWIP. CONWIP/KANBAN Hybrid Method.Production control systems have been widely discussed in the Production Engineering literature. The KANBAN system is the most known among professionals for the control and processing of materials in the shop floor environment due to its simplicity and competitive significance in the design of the Toyota production system. Analyzing possible disadvantages presented by this system, the CONWIP demonstrates that the KANBAN can be questioned in certain circumstances and upon certain variables of the product, demand, or production. The objective of this research is to Investigate, compare, and point out the advantages and disadvantages of KANBAN, CONWIP, and the CONWIP/KANBAN Hybrid Method. Based on the case study in a company that manufactures electromechanical components for valve monitoring and control, characterized by small lots, high customization, and uncertain demand, these methods were discussed in order to show, through the results, the differential combination of KANBAN and CONWIP in the CONWIP/KANBAN Hybrid method..
- Academic research published in the management & production journal (G&P, 1999-2010): Trends and future research directions A produção acadêmica publicada na revista Gestão & Produção de 1999 a 2010: Tendências e direções para pesquisas futuras(2012-01-05) BORTOLLOSSI, L. N.; Mauro SampaioThis study is a review and evaluation of studies published in a Brazilian journal of management & production (G&P) from 1999 to 2010 in order to investigate the diversity of articles in terms of the purposes of research, data collection approaches, and data analysis techniques. The research articles were classified based on their primary purpose (theory building, application, and concepts), data collection approach (case study, qualitative research, archival research, survey-based research, laboratory research, and field research), data analysis technique (descriptive statistics, various multivariate statistical techniques, and mathematical modeling), and operations topics (strategy, quality, and supply chain management). The numbers of articles published increased substantially between 1999 to 2010. The focus of the articles on the manufacturing industry published in this journal changed considerably, and more recently the gap between the number of manufacturing and service-focused articles on production and operations management (POM) has reduced. While previous articles published in the G&P journal were based on conceptual descriptions, our results indicate that the journal has published articles based on theory and application. Case study is the most widely used method for data collection. Directions for future research in operations management were also discussed.
- High-speed grid connected induction generator supported by magnetic bearings(2012-10-25) Fabio Lima; ROSA, F. C.; FUMAGALLI, M. A.This paper proposes an implementation of a high-speed induction generator supported by magnetic bearings and connected to the grid. An indirect field oriented control (IFOC) is used for high performance of the generator side. On the grid side the voltage oriented control (VOC) is applied to guarantee the high quality of the current injected into the grid. The magnetic bearings improve the system performance because the absence of any kind of friction. The maintenance of the system is also reduced. The high speed and the absence of mechanical coupling between the turbine and the generator also improve the system performance as well as reduce the total length of the system. Simulation results were carried out with the Matlab/Simulink software. An experimental test bench was constructed to prove the system performance and experimental results are in progress. © 2012 IEEE.
- Development of a high-speed turbo-generator supported by active magnetic bearings(2012-10-25) ROSA, F. C.; Fabio Lima; FUMAGALLI, M. A.This paper presents the construction of a mechanical shaft supported by active magnetic bearings (AMB), reproducing a prototype of a turbogenerator. In turbogenerators, the shaft is supported by two radial and one axial magnetic bearings. At the center of the shaft was inserted a rotor of an induction machine, which will operate as motor as well as generator, and at the shaft extremity is coupled a small turbine. The mechanical modeling and assembly are presented in details. After that the control system of the AMB is introduced. Simulations and experimental results are presented to validate the AMB. The high speed AMB supported shaft reduces the length of the system as well as losses and increases the system efficiency. The validation of the high-speed shaft supported by AMB allows the energy generation, in the future, provided by the asynchronous generator mounted upon the shaft. Prime mover like gas will be considered to provide the mechanical power. © 2012 IEEE.
- Speed neuro-fuzzy estimator applied to sensorless induction motor control(2012) Fabio Lima; KAISER, W.; SILVA, I. N.; OLIVEIRA, A. A.This work proposes the development of an Adaptive Neuro-fuzzy Inference System (ANFIS) estimator applied to speed control in a three-phase induction motor sensorless drive. Usually, ANFIS is used to replace the traditional PI controller in induction motor drives. The evaluation of the estimation capability of the ANFIS in a sensorless drive is one of the contributions of this work. The ANFIS speed estimator is validated in a magnetizing flux oriented control scheme, consisting in one more contribution. As an open-loop estimator, it is applied to moderate performance drives and it is not the proposal of this work to solve the low and zero speed estimation problems. Simulations to evaluate the performance of the estimator considering the vector drive system were done from the Matlab/Simulink software. To determine the benefits of the proposed model, a practical system was implemented using a voltage source inverter (VSI) to drive the motor and the vector control including the ANFIS estimator, which is carried out by the Real Time Toolbox from Matlab/Simulink software and a data acquisition card from National Instruments. © 2012 IEEE.
- Technological capability development: The role of Infrastructural Technology A capacitação tecnológica na empresa: a função da Tecnologia Industrial Básica (TIB)(2013-04-2013) GALLINA, R.; FLEURY, A.The mastering of Infrastructural Technologies (IfT) - metrology, standardization, and conformity assessment - is not only a precondition for a firm's competitiveness, since it enables production in accordance with international norms; but it is also a requisite for the effective accumulation of technological capabilities aiming at technological innovations. In the specialized literature, there is a lack of studies that address the role of Infrastructural Technologies in the technology learning process. This article aims to fill that gap by proposing a model to assess and design the dynamic interrelationships between IfT and technological capability development. This model compares the mechanisms required in each one of the stages of IfT maturity to the organizational processes adopted by firms with different levels of technological capability reported in the literature. The data were collected through a survey of a sample of 103 metal-mechanics firms. It can be concluded that there is a strong relationship between the IfT's level of maturity and the firms' level of technological capability. In other words, the development of capability in IfT seems to be a precondition for the firms' technological development and innovation strategy.
- Behavioral Persona for human-robot interaction: A study based on pet robot(2014-06-22) DOS SANTOS, T. F.; DE CASTRO, D. G.; MASIERO, A. A.; Plinio Thomaz Aquino JuniorWith the advancement of technology robots have become more common in every day applications, like Paro and GOSTAI Jazz for health care or Pleo and Genibo for entertainment. Since these robots are designed to constantly interact with people, during the development process it should be considered how people would feel and behave when they interact with those artifacts. However there might be some issues in collecting this type of data or how to efficiently use it in the development of new features. In this study we report a process for creating Personas that will help in the design of subject-focused applications for robots interactions. © 2014 Springer International Publishing.