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Performance Analysis of a Novel Triple-Permanent-Magnet-Excited Magnetic Gear and Its Design Method

IEEE TRANSACTIONS ON MAGNETICS 2016年第7期52卷 8001304-1-8001304-4页

作者： Chen, Yiduan Fu, W. N. Li, Wei Hong Kong Polytech Univ Dept Elect Engn Hong Kong Hong Kong Peoples R China Tongji Univ Dept Elect Engn Shanghai Peoples R China

This paper proposes a novel triple-permanent-magnet-excited (TPME) magnetic gear (MG) with an extra stationary layer of permanent magnets (PMs) sandwiched between adjacent ferromagnetic segments to produce an additional torque and in which a simplified consequent-pole Halback array-type PM arrangement is employed to improve the magnetic field characteristic. The novel TPME-MG has a higher torque transmission density when compared with its conventional counterpart. Its design method using the numerical finite-element method and the optimization algorithm is presented. The novel TPME-MG with optimal PM arrangement can significantly achieve higher torque density and torque per PM volume. The results of finite-element computation show that the proposed TPME-MG with optimal PM arrangement has over 74% higher torque density (torque per unit overall volume) and more than 37% higher torque per PM volume compared with a conventional surface-mounted MG, and can reach 51% higher torque density and 34% higher torque per PM volume compared with an original design of TPME-MG, which validates the effectiveness of the design method for the PM arrangement in the novel TPME-MG.

关键词： Design method finite-element method (FEM) magnetic field magnetic gear (MG) optimization algorithm

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On the Computation and Accuracy of Trajectory State Transition Matrices

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第11期39卷 2485-2499页

作者： Pellegrini, Etienne Russell, Ryan P. Univ Texas Austin Dept Aerosp Engn & Engn Mech 210 E 24th St Austin TX 78712 USA

State transition matrices provide sensitivities or partial derivatives between states at different times along a trajectory and are used for a number of applications such as feedback controls, stability analysis, estimation, targeting, parameter optimization, and optimal control. The need for accurate state transition matrices is especially important for problems and applications that have highly sensitive and highly nonlinear dynamics. In this paper, examples are considered in the context of multiple-revolution and multiple-body space trajectories. Three techniques to compute both the first- and second-order state transition matrices are compared: 1)augmenting the state with the classic variational equations, 2)complex and bicomplex-step derivative approximation, and 3)multipoint stencils for traditional finite differences. Each of the methods are compared for accuracy and speed across a variety of problems and numerical integration techniques. The subtle differences between variable- and fixed-step integration for partial computation are revealed, common pitfalls are observed, and recommendations are made to enhance the quality of state transition matrices. A main result is the demonstration of small but potentially significant errors in the partials when they are computed with variational equations and a variable-step integrator.

关键词： Trajectory optimization Predictor Corrector Method Nonlinear Dynamics Feedback Control Finite Difference Approximation FORTRAN optimization algorithm Sensitivity Analysis Computing Black Box

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Investigating the optical XNOR gate using plasmonic nano-rods

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PHOTONICS AND NANOSTRUCTURES-FUNDAMENTALS AND APPLICATIONS 2016年 19卷 24-30页

作者： Akhlaghi, Majid Kaboli, Milad Islamic Azad Univ Omidiyeh Branch Young Researchers & Elite Club Omidiyeh Iran Islamic Azad Univ Omidiyeh Branch Dept Elect & Elect Omidiyeh Iran

In this paper, a coherent perfect absorption (CPA)-type XNOR gate based on plasmonic nano particle is proposed. It consists of two plasmonic nano rod arrays on top of two parallel arms with quartz substrate. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nano-particles waveguide. Since the CPA efficiency depends strongly on the number of plasmonic nano-rod and the nano rod location, an efficient binary optimization method based the Particle Swarm optimization (PSO) algorithm is used to design an optimized array of the plasmonic nano-rod in order to achieve the maximum absorption coefficient in the 'off' state and the minimum absorption coefficient in the 'on' state. In Binary PSO (BPSO), a group of birds consists a matrix with binary entries, control the presence ('1') or the absence ('0') of nano rod in the array. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Plasmonic nano particles optimization algorithm Optical gate

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Studying lowest energy structures of carbon clusters by bond-order empirical potentials

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THEORETICAL CHEMISTRY ACCOUNTS 2016年第1期136卷 1-13页

作者： Lai, S. K. Setiyawati, Icuk Yen, T. W. Tang, Y. H. Natl Cent Univ Dept Phys Complex Liquids Lab Chungli 320 Taiwan Natl Cent Univ Dept Phys Computat Mat Grp Chungli 320 Taiwan Natl Cent Univ Dept Phys Nanoscale Transport Grp Chungli 320 Taiwan

A very recently developed optimization algorithm for carbon clusters (C (n) s) (Yen and Lai J Chem Phys 142:084313, 2015) is combined separately with different empirical bond-order potentials which were proposed also for carbon materials, and they are applied to calculate the lowest energy structures of C (n) s studying their structural changes at different size n. Based on predicted structures, we evaluate the practicality of four analytic bond-order empirical potentials, namely the Tersoff, Tersoff-Erhart-Albe, first-generation Brenner and second-generation Brenner (SGB) potentials. Generally, we found that the cluster C (n) (n = 3-60) obtained by the SGB potential undergoes a series of dramatic structural transitions, i.e., from a linear -> a single ring -> a multi-ring/quasi-two-dimensional bowl-like -> three-dimensional fullerene-like shape;such variability of structural forms was not seen in the other three potentials. On closer examination of the C (n) s calculated using this potential and further comparing them with those obtained by the semiempirical density functional tight-binding theory calculations, we found that these C (n) are more realistic than similar works reported in the literature. In this respect, due to its potential applications in the study of chemically complex systems of different atoms especially chemical reactions (Che et al. Theor Chem Acc 102:346, 1999), the SGB potential can, moreover, be used to investigate larger size C (n) , and calculated structural results by this potential are naturally input configurations for higher-level density functional theory calculations. Another most remarkable finding in the present work is the C (n) results calculated by Tersoff-Erhart-Albe empirical potential. It predicts a two-dimensional development of graphene structure, exhibiting always a zigzag edge in the optimized clusters. This empirical potential can thus be applied to study graphene-related materials such as that shown in a recent paper (Y

关键词： Carbon cluster optimization algorithm Topological transition Fullerene

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PI controller design using artificial bee colony algorithm for MPPT of photovoltaic system supplied DC motor-pump load

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COMPLEXITY 2016年第6期21卷 99-111页

作者： Oshaba, A. S. Ali, E. S. Abd Elazim, S. M. Power Elect & Energy Convers Elect Res Inst NRC Bldg Giza 12311 Egypt Jazan Univ Fac Engn Dept Elect Jazan Saudi Arabia Zagazig Univ Fac Engn Elect Power & Machine Dept Zagazig Egypt

Maximum Power Point Tracking (MPPT) is used in Photovoltaic (PV) systems to maximize its output power. A new MPPT system has been suggested for PV-DC motor pump system by designing two PI controllers. The first one is used to reach MPPT by monitoring the voltage and current of the PV array and adjusting the duty cycle of the DC/DC converter. The second PI controller is designed for speed control of DC series motor by setting the voltage fed to the DC series motor through another DC/DC converter. The suggested design problem of MPPT and speed controller is formulated as an optimization task which is solved by Artificial Bee Colony (ABC) to search for optimal parameters of PI controllers. Simulation results have shown the validity of the developed technique in delivering MPPT to DC series motor pump system under atmospheric conditions and tracking the reference speed of motor. Moreover, the performance of the ABC algorithm is compared with Genetic algorithm for various disturbances to prove its robustness. (c) 2015 Wiley Periodicals, Inc. Complexity 21: 99-111, 2016

关键词： photovoltaic system optimization algorithm maximum power point tracking PI controller DC series motor pump system

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Spatial distribution estimation of malaria in northern China and its scenarios in 2020, 2030, 2040 and 2050

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MALARIA JOURNAL 2016年第1期15卷 1-16页

作者： Song, Yongze Ge, Yong Wang, Jinfeng Ren, Zhoupeng Liao, Yilan Peng, Junhuan China Univ Geosci Sch Land Sci & Technol Beijing Peoples R China Chinese Acad Sci State Key Lab Resources & Environm Informat Syst Inst Geog Sci & Nat Resources Res Beijing Peoples R China Chinese Ctr Dis Control & Prevent Key Lab Surveillance & Early Warning Infect Dis Beijing Peoples R China Univ Chinese Acad Sci Beijing Peoples R China

Background: Malaria is one of the most severe parasitic diseases in the world. Spatial distribution estimation of malaria and its future scenarios are important issues for malaria control and elimination. Furthermore, sophisticated nonlinear relationships for prediction between malaria incidence and potential variables have not been well constructed in previous research. This study aims to estimate these nonlinear relationships and predict future malaria scenarios in northern China. Methods: Nonlinear relationships between malaria incidence and predictor variables were constructed using a genetic programming (GP) method, to predict the spatial distributions of malaria under climate change scenarios. For this, the examples of monthly average malaria incidence were used in each county of northern China from 2004 to 2010. Among the five variables at county level, precipitation rate and temperature are used for projections, while elevation, water density index, and gross domestic product are held at their present-day values. Results: Average malaria incidence was 0.107 % per annum in northern China, with incidence characteristics in significant spatial clustering. A GP-based model fit the relationships with average relative error (ARE) = 8.127 % for training data (R-2 = 0.825) and 17.102 % for test data (R-2 = 0.532). The fitness of GP results are significantly improved compared with those by generalized additive models (GAM) and linear regressions. With the future precipitation rate and temperature conditions in Special Report on Emission Scenarios (SRES) family B1, A1B and A2 scenarios, spatial distributions and changes in malaria incidences in 2020, 2030, 2040 and 2050 were predicted and mapped. Conclusions: The GP method increases the precision of predicting the spatial distribution of malaria incidence. With the assumption of varied precipitation rate and temperature, and other variables controlled, the relationships between incidence and the varied variables appea

关键词： Malaria Genetic programming Remote-sensing data Future distribution prediction Climate change scenarios optimization algorithm

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Immuno-hybrid algorithm: a novel hybrid approach for GRN reconstruction

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3 BIOTECH 2016年第2期6卷 1-10页

作者： Jereesh, A. S. Govindan, V. K. Cochin Univ Sci & Technol Dept Comp Sci Cochin Kerala India Indian Inst Informat Technol Pala Dept Comp Sci & Engn Kottayam Kerala India

Bio-inspired algorithms are widely used to optimize the model parameters of GRN. In this paper, focus is given to develop improvised versions of bio-inspired algorithm for the specific problem of reconstruction of gene regulatory network. The approach is applied to the data set that was developed by the DNA microarray technology through biological experiments in the lab. This paper introduced a novel hybrid method, which combines the clonal selection algorithm and BFGS Quasi-Newton algorithm. The proposed approach implemented for real world E. coli data set and identified most of the relations. The results are also compared with the existing methods and proven to be efficient.

关键词： Clonal selection algorithm Immuno-hybrid algorithm optimization algorithm Gene regulatory network DNA microarray BFGS Quasi-Newton

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Development of a Computational Approach/Model to Explore NMDA Receptors Functions

Development of a Computational Approach/Model to Explore NMD...

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作者： A. Florence Keller Jean-Marie C. Bouteiller Theodore W. Berger

Modern laboratory techniques allow studying NMDA receptors (NMDAR) either anatomically with specific antibodies coupled to sophisticated confocal microscopy, or physiologically by live imaging or electrophysiological techniques. However, NMDARs are not fixed in time and space and changes in their composition and/or distribution on the post-synaptic membrane may significantly impact the synaptic strength and overall function. The computational modeling approach therefore constitutes a complementary tool for investigating the properties of biological systems based on the knowledge provided by the lab experiments. Here, we describe a general computational method aiming at developing kinetic Markov-chain based models of NMDARs subtypes capable of reproducing various experimental results. These models are then used to make predictions on additional (non-obvious) properties and on their role in synaptic function under various physiological and pharmacological conditions. For the purpose of this book chapter, we will focus on the method used to develop a NMDAR model that includes pharmacological site of action of different compounds. Notably, this elementary model can subsequently be included in a neuron model (not described in detail here) to explore the impact of their differential distribution on synaptic functions. less

关键词： Confocal Microscopy Live Cell Imaging Data Mining Data analysis Programming Language Python Pharmacology Computational model Ordinary differential equation kinetic models NMDA receptors model Synaptic function optimization algorithm

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Adapting and Optimizing the Systemic Model of Banking Originated Losses (SYMBOL) Tool to the Multi-core Architecture

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COMPUTATIONAL ECONOMICS 2016年第2期48卷 253-280页

作者： Muresano, Ronal Pagano, Andrea Commiss European Communities IPSC JRC Financial & Econ Anal Unit Via E Fermi 2749 I-21027 Ispra Italy

Currently, multi-core system is a predominant architecture in the computational word. This gives new possibilities to speedup statistical and numerical simulations, but it also introduce many challenges we need to deal with. In order to improve the performance metrics, we need to consider different key points as: core communications, data locality, dependencies, memory size, etc. This paper describes a series of optimization steps done on the SYMBOL model meant to enhance its performance and scalability. SYMBOL is a micro-funded statistical tool which analyses the consequences of bank failures, taking into account the available safety nets, such as deposit guarantee schemes or resolution funds. However, this tool, in its original version, has some computational weakness, because its execution time grows considerably, when we request to run with large input data (e.g. large banking systems) or if we wish to scale up the value of the stopping criterium, i.e. the number of default scenarios to be considered. Our intention is to develop a tool (extendable to other model having similar characteristics) where a set of serial (e.g. deleting redundancies, loop enrolling, etc.) and parallel strategies (e.g. OpenMP, and GPU programming) come together to obtain shorter execution time and scalability. The tool uses automatic configuration to make the best use of available resources on the basis of the characteristics of the input datasets. Experimental results, done varying the size of the input dataset and the stopping criterium, show a considerable improvement one can obtain by using the new tool, with execution time reduction up to 96 % of with respect to the original serial version.

关键词： optimization algorithm Parallel techniques OpenMP GPU SYMBOL

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Social and Location Analysis for Similarity Assessment: Multiparameter Social Search Based on Social Preferences and User Movements

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INTERNATIONAL JOURNAL OF INTERDISCIPLINARY TELECOMMUNICATIONS AND NETWORKING 2016年第4期8卷 22-33页

作者： Asmaryan, Albert Levanov, Alexey Borovik, Irina Bauman Moscow State Tech Univ Moscow Russia

This article introduces the method to assess similarity based on Facebook Graph API and users' movements. All movements of users are collected and analyzed. This paper presents a two-step multiparameter algorithm that generates recommendations based on users' social activity and movements. A flexible mechanism for the calculations of time that one spends on a variety of social activities to more accurately identify the relationships between users is presented. To reduce the load on the application the algorithms of data analysis and transfer optimization are proposed. The ultimate result of the study is to build a platform based on the "client-server" model and includes a mobile app on the iOS platform and server, which would be set up on the "LAMP" platform. The given result can be used and applied in various spheres of our lives to identify different relationships between people.

关键词： Assessment Model Location Multiparamter Analysis optimization algorithm Similarity algorithm Social Graph Social Networks

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