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2018 International Symposium on Power Electronics, Electrical Drives, Automation and Motion, SPEEDAM 2018

作者： Dos Santos Coelho, Leandro Klein, Carlos Eduardo Mariani, Viviana Cocco Do Nascimento, Carlos Augusto Richter Askarzadeh, Alireza PUCPR Industrial and Systems Eng. Graduate Program PPGEPS Federal University of Parana UFPR Department of Electrical Engineering DEE/PPGEE Pontifical Catholic University of Parana Curitiba PR Brazil PUCPR Mechanical Engineering Graduate Program PPGEM Curitiba Pontifical Catholic University of Parana PR Brazil Department of Energy Management and Optimization Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology Kerman Iran

ISBN: (纸本)9781538649411

Metaheuristic algorithms have provided efficient tools to designers by which it became possible to determine the optimum solutions of optimization problems encountered in several fields such as engineering, finance and computation. Generally metaheuristics are based on metaphors that are taken from nature or some other processes. Recently, an optimization metaheuristic paradigm based on the social behavior of the crows, called crow search algorithm (CSA), has been proposed. The idea of CSA is motivated from the storing process of the excess food in hiding places then restoring it in the necessary time. The CSA has many favorable characteristics, such as ease of implementation, the need to adjust only a few parameters, a favorable balance between search diversification and intensification, and fast convergence and high sensitivity. However, to enhance the performance of the standard CSA approach, this paper proposes to tune the control parameters using population diversity information and normal (Gaussian) probability distribution function. Loney's solenoid benchmark and circular antenna array design problems are used to evaluate the effectiveness of the conventional CSA and the proposed variant. Simulation results and comparisons with the CSA demonstrated that the performance of the proposed MCSA approach is promising in electromagnetics optimization. © 2018 IEEE.

关键词： Optimization

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Modelling and reducing fuel flow pulsation of a fuel-metering system during pump mode switching in a turbofan engine

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IOP Conference Series: Earth and Environmental Science 2019年第5期240卷

作者： S Masuda F Shimizu M Fuchiwaki K Tanaka Control Systems Engineering Department Research & Engineering Division Aero Engines Space & Defense Business Area IHI Corporation 229 Tonogaya Mizuho-machi Nishitama-gun Tokyo 190-1297 Japan Department of Computer Science and Systems Engineering Doctoral Program Graduate School of Computer Science and Systems Engineering Kyushu Institute of Technology 680-4 kawazu Iizuka-shi Fukuoka 820-8502 Japan Department of Mechanical Information Science and Technology School of Computer Science and Systems Engineering Kyushu Institute of Technology 680-4 kawazu Iizuka-shi Fukuoka 820-8502 Japan

In this research, the transient characteristics of a new type fuel metering system for aircraft turbofan engines using two types of pumps, a gear pump and a centrifugal pump, were studied by modelling and simulation. This new fuel metering system is capable of hydraulically unloading the operating state of each pump by the pump mode switching mechanism within the permissible range of the pump rotation speed and the fuel flow rate and it is possible to reduce the fuel temperature rise due to the pressure loss in the circuit in the operation region of the entire fuel system. In addition to this, by using a small centrifugal pump that can realize high discharge flow rate, it is possible to reduce weight compared to the conventional fuel system. However, when the pump mode is switched, unexpected fluctuation in the fuel flow rate can occur when a large change in the inlet pressure of the system occurs, the pressure control unit cannot follow the change, and the transient phenomenon cannot be suppressed. At this time, the pressure waveform generated at the time of changing the pump mode includes a high frequency component such that the pressure control unit, which plays a role of keeping the metering valve differential pressure constant, cannot follow up. Therefore, in this paper, we focused on the frequency of the pressure change waveform when the pump mode was changed and studied the model of the fuel system inlet pressure in the gear pump mode. Based on that model, we propose a method to reduce the frequency characteristics of the pressure change occurring at the time of pump mode change.

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Analyses of protein cores reveal fundamental differences between solution and crystal structures

arXiv

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arXiv 2019年

作者： Mei, Zhe Treado, John D. Grigas, Alex T. Levine, Zachary A. Regan, Lynne O'Hern, Corey S. Integrated Graduate Program in Physical & Engineering Biology Yale University New HavenCT06520 United States Department of Chemistry Yale University New HavenCT06520 United States Department of Mechanical Engineering & Materials Science Yale University New HavenCT06520 United States Graduate Program in Computational Biology & Bioinformatics Yale University New HavenCT06520 United States Department of Pathology Yale University New HavenCT06520 United States Department of Molecular Biophysics and Biochemistry Yale University New HavenCT06520 United States Institute of Quantitative Biology Biochemistry and Biotechnology Center for Synthetic and Systems Biology School of Biological Sciences University of Edinburgh Department of Physics Yale University New HavenCT06520 United States Department of Applied Physics Yale University New HavenCT06520 United States

There have been several studies suggesting that protein structures solved by NMR spectroscopy and x-ray crystallography show significant differences. To understand the origin of these differences, we assembled a database of high-quality protein structures solved by both methods. We also find significant differences between NMR and crystal structures|in the root-mean-square deviations of the Cα atomic positions, identities of core amino acids, backbone and sidechain dihedral angles, and packing fraction of core residues. In contrast to prior studies, we identify the physical basis for these differences by modelling protein cores as jammed packings of amino-acid-shaped particles. We find that we can tune the jammed packing fraction by varying the degree of thermalization used to generate the packings. For an athermal protocol, we find that the average jammed packing fraction is identical to that observed in the cores of protein structures solved by x-ray crystallography. In contrast, highly thermalized packing-generation protocols yield jammed packing fractions that are even higher than those observed in NMR structures. These results indicate that thermalized systems can pack more densely than athermal systems, which suggests a physical basis for the structural differences between protein structures solved by NMR and x-ray crystallography. Copyright © 2019, The Authors. All rights reserved.

关键词： X ray crystallography

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An innovative method to determine optimum insulation thickness based on non-uniform adaptive moving grid

arXiv

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arXiv 2019年

作者： Gasparin, Suelen Berger, Julien Dutykh, Denys Mendes, Nathan LAMA UMR 5127 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Thermal Systems Laboratory Mechanical Engineering Graduate Program Pontifical Catholic University of Paraná Rua Imaculada Conceição 1155 Curitiba - ParanáCEP: 80215-901 Brazil LOCIE UMR 5271 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LAMA Chambéry73000 France

It is well known that thermal insulation is a leading strategy for reducing energy consumption associated to heating or cooling processes in buildings. Nevertheless, building insulation can generate high expenditures so that the selection of an optimum insulation thickness requires a detailed energy simulation as well as an economic analysis. In this way, the present study proposes an innovative non-uniform adaptive method to determine the optimal insulation thickness of external walls. First, the method is compared with a reference solution to properly understand the features of the method, which can provide high accuracy with less spatial nodes. Then, the adaptive method is used to simulate the transient heat conduction through the building envelope of buildings located in Brazil, where there is a large potential of energy reduction. Simulations have been efficiently carried out for different wall and roof configurations, showing that the innovative method efficiently provides a gain of 25% on the computer run time. Copyright © 2019, The Authors. All rights reserved.

关键词： Thermal insulation

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An adaptive simulation of nonlinear heat and moisture transfer as a boundary value problem

arXiv

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arXiv 2019年

作者： Gasparin, Suelen Berger, Julien Dutykh, Denys Mendes, Nathan LAMA UMR 5127 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Thermal Systems Laboratory Mechanical Engineering Graduate Program Pontifical Catholic University of Paraná Rua Imaculada Conceição 1155 Curitiba – ParanáCEP: 80215-901 Brazil LOCIE UMR 5271 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LAMA Chambéry73000 France

This work presents an alternative view on the numerical simulation of diffusion processes applied to the heat and moisture transfer through porous building materials. Traditionally, by using the finite-difference approach, the discretization follows the Method Of Lines (MOL), when the problem is first discretized in space to obtain a large system of coupled Ordinary Differential Equations (ODEs). Thus, this paper proposes to change this viewpoint. First, we discretize in time to obtain a small system of coupled ODEs, which means instead of having a Cauchy (Initial Value) Problem (IVP), we have a Boundary Value Problem (BVP). Fortunately, BVPs can be solved efficiently today using adaptive collocation methods of high order. To demonstrate the benefits of this new approach, three case studies are presented, in which one of them is compared with experimental data. The first one considers nonlinear heat and moisture transfer through one material layer while the second one considers two material layers. Results show how the nonlinearities and the interface between materials are easily treated, by reasonably using a fourth-order adaptive method. Finally, the last case study compares numerical results with experimental measurements, showing a good agreement. Copyright © 2019, The Authors. All rights reserved.

关键词： Ordinary differential equations

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Energy efficiency effect on the public street lighting by using LED light replacement and kwh-meter installation at DKI Jakarta Province, Indonesia

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Journal of Physics: Conference Series 2018年第1期1022卷

作者： Panggih Sudarmono Deendarlianto Adhika Widyaparaga Master Program of Systems Engineering Faculty of Engineering Universitas Gadjah Mada Department of Mechanical and Industrial Engineering Faculty of Engineering Universitas Gadjah Mada

Public street lighting consumes large energy for the public interest, but many street lights still do not use energy-saving technologies. In 2014, Provincial Government of DKI Jakarta operated 179,305 units of street lights. Of the number of installed armature, 92 % of them or 166,441 units are HPS (High-Pressure Sodium) armatures which are inefficient. In 2016, the Provincial Government of DKI Jakarta cut down the energy used for street lighting, by implementing the programs of kWh-meter installation in every street lighting panel and use energy-saving lamps equipped with the smart system. The Provincial Government of DKI Jakarta is registered with 6,399 customer IDs in PLN (State Owned Electric Company), and gradually carried out the kWh Meter installation and changes to the contract. The program to use energy-saving lights done by replacing the HPS armature that is not energy efficient to LED armature which is known to be energy efficient. Until the end of 2016, the number of armatures that has been replaced was 89,417 units. The research results on 25 samples of PLN customer IDs and the replacement of 2,162 units armature, showed that the energy efficiency through kWh meter installation and armature replacement reduce the power consumption from 330,414 kWh to 71,278 kWh or by 78.43%. Generally, there was a decrease in the value of electricity bill compared to the before the replacement. The program of kWh-meter installations and replacement of the armature has a payback period of 2.66 years.

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Automated 3D bone modelling based on geometric features from images 24

Automated 3D bone modelling based on geometric features from...

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24th International Conference on Production Research, ICPR 2017

作者： Rudek, M. Gumiel, Y.B. Canciglieri, O. Carvalho, D.R. Trajanovic, M. Industrial and Systems Engineering Post-Graduate Program PUCPR Imaculada Conceicao Street 1155 zip code CuritibaParana80215-901 Brazil Graduate Program on Health Technology in Pontifical Catholic University of Parana PUCPR Imaculada Conceicao Street 1155 zip code CuritibaParana80215-901 Brazil Faculty of Mechanical Engineering University of Nis Aleksandra Medvedeva 14 Niš18000 Serbia

ISBN: (纸本)9781605955070

Currently the computational modelling tools, expert algorithms for image segmentation and three-dimensional printing devices have improved the process of manufacture of customized pieces in the context of automation of prosthesis modelling. Among several strategies to obtain the correct shape of a missing bone part, we explore a modelling method based on geometric features defined by Bezier cubic curves. The data is obtained from sets of slices of tomographic scans as a reference. From the images, we know about data from the edges in the image but we do not have any information about a missing area in a specific bone region. Thus, the objective is to search patterns for features whose values are known from similar tomographic image which matches to fill a hole in a bone. Due the free form of a bone there are a lot of parameters to be evaluated. Thus, a Data Mining approach is applied for classification and to discover the best features as shape descriptors. In this way, the prosthesis manufacture can be automated in all stages among image scanning and printing. © 2017 DEStech Publications. All rights reserved.

关键词： Image enhancement

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Diversity-Guided Generalized Extremal Optimization for Transformer Design Problem

Diversity-Guided Generalized Extremal Optimization for Trans...

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IEEE Symposium Series on Computational Intelligence

作者： Leandro dos S. Coelho Viviana C. Mariani Rafael B. Grebogi Emerson H. de Vasconcelos Segundo Mauricio V. Ferreira da Luz Jean V. Leite Roberto Z. Freire Industrial and Systems Engineering Graduate Program Electrical Engineering Federal University of Parana - UFPR Curitiba Brazil Mechanical Engineering Graduate Program Electrical Engineering Federal University of Parana - UFPR Curitiba Brazil Mechanical Engineering Graduate Program Federal Institute of Santa Catarina - IFSC Lages Brazil Mechanical Engineering Graduate Program Pontifical Catholic University of Parana - PUCPR Curitiba Brazil GRUCAD-EEL-CTC Federal University of Santa Catarina - UFSC Florianópolis Brazil Federal University of Santa Catarina - UFSC Florianópolis Brazil Industrial and Systems Engineering Graduate Program Pontifical Catholic University of Parana - PUCPR Curitiba Brazil

Market competitiveness and pressure for rational use of resources led manufacturers to look for optimized electromagnetic devices. The large number of variables involving the design of this technology, as well as the compromise between performance and efficiency, have provide the opportunity to adopt optimization techniques in their design stage. Recently, a wide variety of both traditional and nontraditional mathematical algorithms have been introduced to solve challenging and practical optimization problems related to electromagnetic equipment. Evolutionary metaheuristics are general-purpose optimization algorithms inspired by natural self-organized systems and by biological evolution. An optimization method, called Extremal Optimization (EO), which is based on a simplified model of natural selection, was developed to show the emergence of self-organized criticality based on Bak-Sneppen model in ecosystems. Recently, a generalized version of EO method, called Generalized Extremal Optimization (GEO), was proposed. This technique can be applied to a broad class of design optimization problems. In order to enhance and to improve the search performance and efficiency of GEO, a novel Diversity-guided GEO (DGEO) metaheuristic algorithm, with focus in global continuous optimization, is proposed and investigated in this paper considering the design stage of an electromagnetic device. The analysis was carried for a single-phase transformer and revealed that DGEO provided considerable better performance in convergence speed and solution quality than standard GEO.

关键词： Metaheuristic optimization Transformer design Generalized extremal optimization Power-grid Power conversion

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Using Leaves as a Model for Teaching Watershed Concepts in Natural Resources Science and engineering programs

Natural Sciences Education

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Natural Sciences Education 2017年第1期46卷 1-9页

作者： Anandhi, Aavudai Yang, Yang Hubenthal, Michael Dep. of Special Education Counseling and Student Affairs College of Education Kansas State Univ. Manhattan 66506 KS United States Biological Systems Engineering Florida Agricultural and Mechanical Univ. Tallahassee 32307 FL United States Education and Outreach Program Incorporated Research Institutions for Seismology (IRIS) Washington 20005 DC United States

Core Ideas: Watershed is an important concept in science and engineering of natural resources. Introducing watershed concept using a leaf that students see every day is novel. Using leaf analogy, watershed concept can be taught universally. This article examines the effects of using leaves, something most students see every day and have some familiarity with, as an analogy for the concept of watersheds in an undergraduate water resources engineering course. The ultimate goal of the leaf/watershed analogy and associated instruction is to increase students’ understanding of hydrology principles, which in turn may facilitate better watershed management through increased public awareness, increased adoption of appropriate best management practices, and improved policy decisions. The assessment was performed with junior and senior undergraduate students enrolled in a Water Resource engineering course. The assessment results showed that overall, students benefitted from the leaf analogy as a tool for learning watersheds. However, this effect varied depending on students’ learning style preferences. Copyright © 2017 by the American Society of Agronomy

关键词： watersheds foliage engineering calculating program college student Analogy Water Resources engineering Public awareness Students Water Resources Familiarity

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A new model for simulating heat, air and moisture transport in porous building materials

arXiv

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arXiv 2019年

作者： Berger, Julien Dutykh, Denys Mendes, Nathan Rysbaiuly, Bolatbek Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LOCIE Chambéry73000 France LOCIE UMR 5271 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LAMA Chambéry73000 France LAMA UMR 5127 CNRS Université Savoie Mont Blanc Campus Scientifique Le Bourget-du-Lac CedexF-73376 France Thermal Systems Laboratory Mechanical Engineering Graduate Program Pontifical Catholic University of Paraná Rua Imaculada Conceição 1155 Curitiba - ParanáCEP: 80215-901 Brazil International Information Technology University Manas Str. 34/1 Almaty Kazakhstan

This work presents a detailed mathematical model combined with an innovative efficient numerical model to predict heat, air and moisture transfer through porous building materials. The model considers the transient effects of air transport and its impact on the heat and moisture transfer. The achievement of the mathematical model is detailed in the continuity of Luikov's work. A system composed of two advection-diffusion differential equations plus one exclusively diffusion equation is derived. The main issue to take into account the transient air transfer arises in the very small characteristic time of the transfer, implying very fine discretisation. To circumvent these difficulties, the numerical model is based on the Du Fort-Frankel explicit and unconditionally stable scheme for the exclusively diffusion equation. It is combined with a two-step Runge-Kutta scheme in time with the Scharfetter-Gummel numerical scheme in space for the coupled advection-diffusion equations. At the end, the numerical model enables to relax the stability condition, and, therefore, to save important computational efforts. A validation case is considered to evaluate the efficiency of the model for a nonlinear problem. Results highlight a very accurate solution computed about 16 times faster than standard approaches. After this numerical validation, the reliability of the mathematical model is evaluated by comparing the numerical predictions to experimental observations. The latter is measured within a multi-layered wall submitted to a sudden increase of vapor pressure on the inner side and driven climate boundary conditions on the outer side. A very satisfactory agreement is noted between the numerical predictions and experimental observations indicating an overall good reliability of the proposed model. Copyright © 2019, The Authors. All rights reserved.

关键词： Numerical models

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