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The time and the space waveform of electric and magnetic magnitudes of AC machines are a non-sinusoidal including the case of powered by the grid. The reasons of the deformation are in the actual design layout of electrical machines, at various asymmetry generated in the production or as a result of failures in electric, magnetic and mechanical parts of the machine. The rotating electric machine may...
Topological optimization tool using genetic algorithm as optimization algorithm are known as very expensive in computation time. In this paper, we study an approach to improve performance of topological optimization tool by introducing a dynamic variation of the population size of children during the process of optimization. This method allows to improve performance of each generation by adapting...
Light trapping in solar cells allows for increased efficiency and reduced materials cost. It is well known that a 4n2 factor of enhancement in absorption can be achieved by randomly texturing the surface of the solar cell, where n is the refractive index of the material. However, this limit only holds when the thickness of the solar cell is much greater than the wavelength of light. In the subwavelength...
In terms of future development of stress grading systems for large rotating machines it is required to calculate the electric surface field strength distribution as well as the temperature profile along the stress grading surface with sufficient accuracy. Due to high nonlinear material characteristics the design and optimization of such systems are a very time consuming process. In order to accelerate...
We address the problem of recovering shape, albedo, and illumination from a single grayscale image of an object, using shading as our primary cue. Because this problem is fundamentally underconstrained, we construct statistical models of albedo and shape, and define an optimization problem that searches for the most likely explanation of a single image. We present two priors on albedo which encourage...
The most outstanding feature of emergency distribution is time urgency. Decision maker should use less time to complete the distribution scheme which should guarantee the materials reach the emergency site with less time. At this time it is especially important to choose the optimal path in the decision-making process. This article builds up mathematical model which is based on the emergency logistics...
Due to highly nonlinear material characteristics in combination with electrical-thermal coupled partial differential equations and the complex geometry the design of stress grading systems for large rotating machines is a difficult and time consuming process. In order to accelerate this process, a finite element model is developed. The model takes the nonlinear electrical and thermal coupled material...
Transportation is, on average, responsible for 27% of US greenhouse gas emissions. Consequently, improvements in vehicle design improving fuel economy, and therefore reducing emissions, are an important step towards meeting emission reduction goals. The primary ways to improve vehicle fuel economy include the use of advanced powertrains, improved rolling resistance and aerodynamics, and vehicle lightweighting...
Recently, material decomposition using multi energy photon counting x-ray detector (PCXD) have been one of the very active areas of researches. Even with a few success, decomposition of three materials, including malignant tissue, has been still considered a difficult problem and systematic studies are still required. In this paper, we propose a statistical framework for decomposition of three material...
This paper is focused on the development of an effective method to optimization inversion on constitutive model parameters of bird material in the numerical simulation of bird impact on an aircraft windshield. The experiments of bird impact on a plate under the velocity of 170m/s were performed and the displacements as well as the strains of the plate were measured. The Murnaghan Equation of State...
Abstract-The paper analyzes reactive power optimization problem in distribution system with garbage power plant. Two mathematical models which involve garbage incineration and city rubbish fuel cell are presented based on garbage heating value. A new model for reactive power optimization is proposed where garbage quantity is used as a additional control variable and garbage biggest processing capability...
According to the Multi-Agent technology modeling theory, combined with the actual situation of the cement materials open-pit mine, using adaptive neural-fuzzy inference system (Anfis) and classic modeling method respectively establishes the blasting system agent model, the transportation production system and the broken system agent model. Through the production task distribution coordinate the operation...
This paper proposes a topology optimization method to optimize the distribution of material within an electrical machine using a genetic algorithm (GA) and considering the types of materials used. The rotor structure in a permanent magnet synchronous motor with concentrated windings is used to demonstrate the proposed method; a rectangular current and sinusoidal current excitation scheme are considered...
Injection molding is a nonlinear, multivariable process which involves several critical parameter settings for quality product. Determining optimal parameter settings is the challenging task due to the influence of environonmental conditions on the resin flow within the injection molding machine. This paper deals with various optimization techniques (differential evolution, DE, genetic algorithm,...
Wire Electric Discharge Machining (WEDM) is one of the important non-traditional machining processes for machining of intricate profiles in conductive and difficult to machine materials. The machining performance of this process largely depends on various process parameters, such as applied voltage, ignition pulse current, pulse-off time, pulse duration, serve controlled reference mean voltage, servo-speed...
Mechanical engineers always expect to design a structure which could work properly in its whole lifetime. But there exist many random factors, such as dimension, material property and applied forces. Hence structures based on determinate design could fail with high probability. Reliability-based Topology Optimization (RBTO) is a computer-automated design method which combines reliability analysis...
An economic and practical measure is put forward to realize energy saving and consumption lowering for alumina evaporation process in this paper. Firstly, based on the energy analysis, investigate the system, unit or equipment which has high energy consumption and saving potential in the alumina evaporation process, secondly, by optimizing the process energy, upgrade the equipment, improve existed...
This paper presents the performance analysis of two different multiobjective optimization schemes for a permanent magnet transverse flux motor (TFM) drive, in which soft magnetic composite (SMC) material is employed as the motor core. Firstly, deterministic multiobjective optimization method is introduced for developing the SMC TFM motor drive while taking into account the unique properties of SMC...
This paper attempts to highlight shortcomings in the concept of sustainability and ways to make the concept more workable by presenting the development of an Environmental Management Information System (EMIS) as a combination of discrete event simulation and ecological material flow analysis for production processes. The motivation behind the focus on simulation techniques on one hand and on production...
Parallel efficiency is always a fundamental research field in high performance computing. This paper focuses on parallel computing at high performance computing cluster with CASTEP program, discusses multi-core parallel efficiency in CASTEP, and analyses the influence of the main calculation parameters upon total CPU time and memory usage in case study, such as CPU cores(CPUs), cutoff energy, k-point,...
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