Maua Institute of Technology

Maua, Brazil

Maua Institute of Technology

Maua, Brazil
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Vitor F.,Kansas State University | Santos V.A.,DDV Credit Advisory | Chwif L.,Maua Institute of Technology
Proceedings - Winter Simulation Conference | Year: 2017

This paper highlights some of the primary concerns about simulation recently raised by academics and practitioners. These concerns influenced the creation of a successful simulation project that improves the check-in at Congonhas Airport in São Paulo, Brazil. Use of simulation was essential in Congonhas because, although significant growth in the number of passengers has occurred over the last decades, Congonhas has limited capacity for expansion due to its location. Two major airlines, which represent 88% of the market share of Congonhas, were considered in this study. Output results demonstrated that a majority of future customers will experience excessive wait times to check in. Therefore, improvement scenarios were proposed in order to meet comfort levels required by international organizations. © 2016 IEEE.


Romano R.A.,University of Sao Paulo | Romano R.A.,Maua Institute of Technology | Garcia C.,University of Sao Paulo
Journal of Process Control | Year: 2011

Among several process variability sources, valve friction and inadequate controller tuning are supposed to be two of the most prevalent. Friction quantification methods can be applied to the development of model-based compensators or to diagnose valves that need repair, whereas accurate process models can be used in controller retuning. This paper extends existing methods that jointly estimate the friction and process parameters, so that a nonlinear structure is adopted to represent the process model. The developed estimation algorithm is tested with three different data sources: a simulated first order plus dead time process, a hybrid setup (composed of a real valve and a simulated pH neutralization process) and from three industrial datasets corresponding to real control loops. The results demonstrate that the friction is accurately quantified, as well as "good" process models are estimated in several situations. Furthermore, when a nonlinear process model is considered, the proposed extension presents significant advantages: (i) greater accuracy for friction quantification and (ii) reasonable estimates of the nonlinear steady-state characteristics of the process. © 2010 Elsevier Ltd. All rights reserved.


Alves V.A.O.,Maua Institute of Technology | Juliani Correa De Godoy R.,University of Sao Paulo | Garcia C.,University of Sao Paulo
Proceedings of the IEEE International Conference on Control Applications | Year: 2012

In some system identification methods, high order ARX models are adopted as true descriptions of the process to be identified. Afterwards, such high order model is used as a basis for a model order reduction procedure. The optimization strategy for the search of the best high order (in the fit index sense) for SISO ARX models, presented in a related paper [1], is extended to the MIMO case. The analyzed system is the Wood & Berry binary distillation column [2]. In this study, the search for the best dead times associated with the high order ARX model is also addressed. The results obtained by the optimization strategy are compared with those derived by exhaustive search. © 2012 IEEE.


Malvezzi F.,Maua Institute of Technology | Coelho T.A.H.,University of Sao Paulo
Mechanisms and Machine Science | Year: 2015

This work deals with the singularity and workspace analyses of a threedegree- of-freedom mechanism for rear independent suspensions, capable to adjust simultaneously the camber, rear steering and roll angles. This mechanism is able to improve handling performance when compared to the vehicle with a passive suspension mechanism. The inverse kinematic model was developed for the velocity kinematic analysis. The Jacobian matrices are applied to investigate the mechanism singularity configuration. Finally, the reachable workspace is obtained using the discretization method. The obtained results have shown there is not singular configuration inside the specified workspace. The available workspace can attend the camber and rear steering angles stroke. Moreover, this workspace can be obtained by using standard joints and actuators. © Springer International Publishing Switzerland 2015.


Coelho T.A.H.,University of Sao Paulo | Malvezzi F.,Maua Institute of Technology
Mechanisms and Machine Science | Year: 2015

The paper presents an asymmetric three-degree-of-freedom parallel mechanism purposely conceived as a robotic device for tool positioning applications. The kinematic structure of the mechanism contains one central passive limb that constrains the end-effector motion to two translations and one rotation. This work deals with important issues related to the parallel mechanism, such as the position kinematics analysis and the singular configurations prediction. © Springer International Publishing Switzerland 2015.


Barbosa M.S.,University of Sao Paulo | Todorov S.D.,University of Sao Paulo | Jurkiewicz C.H.,Maua Institute of Technology | Franco B.D.G.M.,University of Sao Paulo
Food Control | Year: 2015

Bacteriocins of lactic acid bacteria (LAB) have been extensively studied due to their possible applications in food preservation. However, components of the food matrix may interfere or inhibit bacteriocin production, and entrapment of the bio-protective strains may protect them of the adverse conditions in the food environment. In this study, a bacteriocinogenic LAB (Lactobacillus curvatus MBSa2) isolated from salami was entrapped in calcium alginate and tested for functionality in MRS broth and in salami experimentally contaminated with Listeria monocytogenes AL602/08 (a meat isolate), during 30 days simulating manufacture process conditions, including fermentation and maturation steps. The entrapment process did not affect bacteriocin production by Lb. curvatus MBSa2 in MRS broth and in salami. Both, free and entrapped Lb. curvatus MBSa2 caused reduction in a similar manner in the counts of L.monocytogenes AL602/08 in salami during manufacture process. © 2014 Elsevier Ltd.


Triboli E.P.D.R.,Maua Institute of Technology | Gut J.A.W.,University of Sao Paulo
International Journal of Food Engineering | Year: 2016

The objective of this study was to determine suitable conditions for yoghurt spray drying in a pilot-scale equipment with a rotary atomizer using drying auxiliary agents to reduce wall deposition in the drying chamber. First, the effects of the main process variables (disk rotation speed: 25,000-30,000 rpm; inlet air temperature: 160-180 °C; feed flow rate: 5.2-8.7 kg/h) were studied with a 23 central composite experimental design. Following, six different drying agents (maltodextrins 5 dextrose equivalent [DE] and 10 DE, EmCap®, acacia gum, skimmed milk and fumed silica) were tested to identify the most promising additive to improve process yield. Excellent results on wall deposition, product recovery, product color and particle size distribution span were achieved with fumed silica Aerosil® at 3 %, 26,000-rpm atomizer speed, 160 °C inlet air temperature and 8.7 kg/h yoghurt feed flow rate. The action of the fumed silica on particle agglomerates produced a free-flowing powder with good homogeneity. © 2016 by De Gruyter.


Albanez R.,Maua Institute of Technology | Nitz M.,Maua Institute of Technology | Taranto O.P.,University of Campinas
Advanced Powder Technology | Year: 2013

The objective of this work was to study the coating process of diclofenac sodium pellets, with the commercial aqueous coating suspension for enteric release-Acryl-Eze® MP, in a fluid bed coater with a Wurster insert. Coating experiments were performed following a 22 factorial design to determine the influence of process variables on coating performance, measured by the two response variables: efficiency (η%) and agglomeration index (magg%). Both response variables were found to be affected by inlet temperature and suspension flow rate with a 95% confidence level. This work also studied the release of diclofenac sodium coated and uncoated pellets in HCl 0.1 N and pH 6.8 phosphate buffer media. Results showed that the release of diclofenac sodium during the buffer stage was affected by the prior exposure to the HCl 0.1 N medium and a polymer weight gain above 9.7% (2.7 mg/cm 2), was needed to modify the release in such a way that it remained below 10% for the first 120 min in HCl 0.1 N and above 75% in pH 6.8 for the next 45 min. Neither the drug content nor the release profiles were significantly affected by storage at 40 °C and 75% relative humidity. © 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.


Cutri R.,Maua Institute of Technology
Proceedings of the 2010 IEEE International Symposium on Sustainable Systems and Technology, ISSST 2010 | Year: 2010

The global crisis had caused the decline of many financial institutions and had caused many problems in Brazil and abroad, which raises the question: how to increase profits at a time of crisis? In a decreasing consumption situation corporations must reducing energy costs to improve operating profit. Energy management is an important tool to solve this problem. In Brazil information about energy management became more present in university and business world. This paper presents impressions gained when presentation of the subject of energy management to companies of different sectors and discusses the presentation of this subject in the corporate environment.


Da Silva C.A.M.,University of Campinas | Butzge Jr. J.,University of Campinas | Nitz M.,Maua Institute of Technology | Taranto O.P.,University of Campinas
Advanced Powder Technology | Year: 2014

This review presents a compilation of works of the main techniques for monitoring and control fluidization regimes, particle size and moisture content during coating and granulation processes in the fluidized bed. The development of monitoring and control systems for coating and granulation of particles is highly desirable, not only to allow the operation in a stable bubbling fluidization regime, which intensifies heat and mass transfer, but also to ensure strict quality specifications for products, such as, uniform particle size distribution, low moisture content and good flowability. This paper focuses on the discussion of methods used and results obtained in studies on monitoring and control of granulation and coating process in the fluidized bed reported in the literature in the last decades. Pressure fluctuation signal analysis is widely discussed as a tool of regime monitoring. To monitor particle size, techniques such as, Near Infrared spectroscopy (NIR), Focused Beam Reflectance Measurements (FBRMs), among others are presented in detail. As for moisture content tracking, the methods are reviewed like acoustic signals, capacitance, microwave resonance and spectroscopy. It is evident that although these processes are highly complex, the techniques presented here have evolved mainly due to the efforts of several research groups, showing great potential for applications in industry, emphasizing the importance of this research field. © 2013 The Society of Powder Technology Japan. Published by Elsevier B.V.

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