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42nd Conference of the Industrial Electronics Society, IECON 2016

作者： Perez-Basante, Angel Ceballos, Salvador Konstantinou, Georgios Pou, Josep Andreu, Jon De Alegría, Íñigo Martinez Bilbao Spain Tecnalia Research and Innovation Derio Spain University of New South Wales Sydney Australia Nanyang Technological University Singapore Singapore

ISBN: (纸本)9781509034741

Selective harmonic elimination (SHE) - pulse with modulation (PWM), when applied to multilevel converters (MCs), can be optimized in case a half-wave (HW) symmetry is implemented. This kind of symmetry is able to provide a wide variety of solutions. This paper proposes a novel method, based on optimization algorithms, which provides a universal formulation of the SHE-PWM problem with HW symmetry, in such a way that different equation systems are not required to find a solution when different switching patterns are considered. In this way, the proposed technique is able to search simultaneously both the switching patterns and their associated firing angles that solve the SHE-PWM problem, without using predefined waveforms. Therefore, the search process is significantly simplified and the flexibility to find solutions with different waveforms, throughout the reference modulation index, ma, range, is increased. Different sets of solutions provided by this method have been presented and simulation results, obtained from a five-level modular multilevel converter (MMC), have proved the validity of the new proposed technique. © 2016 IEEE.

关键词： Half-wave (HW) symmetry Multilevel converters (MCs) optimization algorithm Selective harmonic elimination (SHE)

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Optimizing Last Mile Delivery using Public Transport with Multi-Agent based Control

Optimizing Last Mile Delivery using Public Transport with Mu...

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作者： Rajeshwari, Chatterjee LAPPEENRANTA UNIVERSITY OF TECHNOLOGY

学位级别：硕士

The majority of research work carried out in the field of Operations-Research uses methods and algorithms to optimize the pick-up and delivery problem. Most studies aim to solve the vehicle routing problem, to accommodate optimum delivery orders, vehicles etc. This paper focuses on green logistics approach, where existing Public Transport infrastructure capability of a city is used for the delivery of small and medium sized packaged goods thus, helping improve the situation of urban congestion and greenhouse gas emissions reduction. It carried out a study to investigate the feasibility of the proposed multi-agent based simulation model, for efficiency of cost, time and energy consumption. Multimodal Dijkstra Shortest Path algorithm and Nested Monte Carlo Search have been employed for a two-phase algorithmic approach used for generation of time based cost matrix. The quality of the tour is dependent on the efficiency of the search algorithm implemented for plan generation and route planning. The results reveal a definite advantage of using Public Transportation over existing delivery approaches in terms of energy efficiency.

关键词： multi-agents travelling salesman Monte-Carlo search optimization algorithm operations research

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Research on the route optimization for fresh air processing of air handling unit in spacecraft launching site

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APPLIED THERMAL ENGINEERING 2015年 86卷 292-300页

作者： Yang, Yongli Jiang, Pengcheng Cong, Hua Feng, Fuzhou Zhang, Hongxing Acad Armored Forces Engn Dept Mech Engn Beijing 100072 Peoples R China Taiyuan Satellite Launch Ctr Taiyuan 036304 Peoples R China

The existing control methods for Air handling units (AHUs) in spacecraft launching site (SLS) are comparatively dated, the air processing routes are usually arbitrarily determined in line with experience, which fails to cope with the coupling and function redundancy of air condition system and the diversity of outdoor environment, therefore resulting in tremendous energy waste. This paper proposes a new route optimization strategy for fresh air processing-Firstly analyzing the possibly processing routes for fresh air based on psychrometric chart, then proposing an optimization algorithm AFSA-GA to optimize the possibly processing routes, eventually obtaining the best route that requires the least energy consumption. By adopting the strategy proposed to optimize air processing route for High-Temperature and High-Humidity working conditions, it can be proved that the proposed strategy can decrease considerable amount of energy consumption, and the proposed optimization algorithm AFSA-GA has the advantages of faster convergence speed and avoiding premature. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： AHU Fresh air processing Psychrometric chart Route optimization optimization algorithm

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New optimization Strategy for Design of Active Twist Rotor

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AIAA JOURNAL 2015年第2期53卷 436-448页

作者： Kumar, Devesh Cesnik, Carlos E. S. Univ Michigan Dept Aerosp Engn Ann Arbor MI 48105 USA

This paper presents the development of a mixed-variable optimization framework for the aeroelastic analysis and design of active twist rotors. Proper tailoring of the blade properties can lead to the maximization of the active twist and the control authority for vibration reduction under operating conditions. Thus, using mathematical optimization, the cross-sectional layout is designed using continuous and discrete design variables for an active composite rotor blade to maximize the dynamic active twist while satisfying a series of constraints on blade cross-section parameters, stiffness, and strength. The optimization framework developed includes the Intelligent Cross-Section Generator as the cross-section and mesh generator, University of Michigan/Variational Asymptotic Beam Sectional analysis code for active cross-sectional analysis, and Rotorcraft Comprehensive Analysis Software for aeroelastic analysis of the active twist rotor blade. The optimization problem is solved using a surrogate-based approach in combination with the Efficient Global optimization algorithm. In this paper, the results with mixed design variables are obtained with three different techniques and are compared with the results obtained using continuous design variables.

关键词： Rotor Blades Aeroelastic Stability Twisted Rotor Blade Rotorcrafts Mathematical optimization optimization algorithm Finite Element Analysis Aerodynamic Characteristics Surrogate Model Genetic algorithm

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A Novel Multiband Frequency Reconfigurable PIFA Antenna

A Novel Multiband Frequency Reconfigurable PIFA Antenna

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International Conference on Advanced Technologies for Communications (ATC)

作者： Pham Trung Minh To Thi Thao Nguyen Trong Duc Vu Van Yem Hanoi Univ Sci & Technol Sch Elect & Telecommun Hanoi Vietnam Vietnam Maritime Univ Fac Informat Technol Haiphong Vietnam Posts & Telecommun Inst Technol Fac Fundamental Sci Ho Chi Minh City Vietnam

ISBN: (纸本)9781509027118

In this paper, we design and implement a novel six-band frequency reconfigurable Planar Inverted-F Antenna (PIFA) for GSM1800, WCDMA, m-WiMAX and WLAN applications. The antenna consists of three radiator patches whose optimal parameters are iteratively selected on different configurations using Genetic algorithm (GA). PIN-diodes are used in appropriate locations to accurately control the operating frequency bands. Simulation results show that depending on ON/OFF states of the PIN-diodes, the antenna can operate in six applicable frequency bands i.e., 1.8 GHz, 2.1 GHz, 2.4 GHz, 3.5 GHz, 3.7 GHz and 5.8 GHz with corresponding peak gains of 3.34 dBi, 2.8 dBi, 5.16 dBi, 3.95 dBi, 5.05 dBi and 6.98 dBi, respectively. The efficiency of the six frequency bands is spread from 64% to 96%. The overall size of the radiated parts is 42.5x20 mm(2) which makes it easy and possible to be integrated into small wireless handsets. Measurements have also been carried out on a fabricated prototype in order to validate the correctness our design.

关键词： PIFA frequency reconfigurable antenna PIN diode optimization algorithm

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A Brief Overview on Parameter optimization of Support Vector Machine

A Brief Overview on Parameter Optimization of Support Vector...

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3rd International Conference on Smart Materials and Nanotechnology in Engineering(SMNE 2016)

作者： Qi Cao Lei Yu Mingsheng Cheng Department of Training Logistical Engineering University College of Computer and Information Science Chongqing Normal University Logistics College Naval University of Engineering

Support vector machine(SVM) has been successfully applied in classification and regression *** it is very sensitive to the selection of *** fundamental principles of SVM are analyzed *** main optimization methods and achievements for SVM parameters are *** the popular fitness functions used for the parameter optimization of SVM are *** objective of this paper is to provide readers a brief overview of the recent advances for parameter optimization of SVM and enable them to develop and implement new optimization strategies for SVM-related research at their disposal.

关键词： Support vector machine Parameter selection optimization algorithm Fitness function

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Combining Shaping and Flow Control for Aerodynamic optimization

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AIAA JOURNAL 2015年第4期53卷 888-901页

作者： Zhang, M. He, L. Univ Oxford Dept Engn Sci Parks Rd Oxford OX1 3PJ England Univ Oxford Dept Engn Sci Computat Aerothermal Engn Oxford OX1 3PJ England

Shape optimization and flow control have been extensively studied in the past to improve the performance of wings and blades. However, they are commonly applied as two separate disciplines, with their interactions being rarely studied. The present work aims to examine and identify the potential to explore the interactions between the two disciplines and is chiefly concerned about two related issues: 1) how much more performance improvement can be obtained by combining the shape optimization with the flow control optimization, and 2) the effects of the sequencing of the disciplines when the optimizations are combined. To address these issues, five optimization approaches have been studied, representing the shaping only, the flow control optimization only, and three different sequencings of the disciplines in the combined optimizations. All the optimization approaches are applied consistently by using the same optimization system developed in this research. The system uses the Kriging surrogate method as the optimization algorithm, and it incorporates a standard computational fluid dynamics solver for which the validity and numerical sensitivities have been assessed. The developed methodology is applied to two optimization cases of practical interest: a compressor blade and a circulation controlled airfoil. The results of both cases show that, when shaping and flow control optimizations are combined, the performance enhancement is considerably higher than when the two disciplines are applied separately. Furthermore, in the combined optimizations for the airfoil, it is observed that the concurrent optimization leads to the highest performance, whereas the sequential optimizations tend to be stuck at less optimal solutions.

关键词： Circulation Controlled Airfoil Shape optimization Control optimization Design of Compressor CFD optimization algorithm Flow Conditions Aerodynamic Efficiency Freestream Mach Number Reynolds Averaged Navier Stokes

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Edge-Preserving PET Image Reconstruction Using Trust optimization Transfer

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IEEE TRANSACTIONS ON MEDICAL IMAGING 2015年第4期34卷 930-939页

作者： Wang, Guobao Qi, Jinyi Univ Calif Davis Dept Biomed Engn Davis CA 95616 USA

Iterative image reconstruction for positron emission tomography can improve image quality by using spatial regularization. The most commonly used quadratic penalty often oversmoothes sharp edges and fine features in reconstructed images, while nonquadratic penalties can preserve edges and achieve higher contrast recovery. Existing optimization algorithms such as the expectation maximization (EM) and preconditioned conjugate gradient (PCG) algorithms work well for the quadratic penalty, but are less efficient for high-curvature or nonsmooth edge-preserving regularizations. This paper proposes a new algorithm to accelerate edge-preserving image reconstruction by using two strategies: trust surrogate and optimization transfer descent. Trust surrogate approximates the original penalty by a smoother function at each iteration, but guarantees the algorithm to descend monotonically;optimization transfer descent accelerates a conventional optimization transfer algorithm by using conjugate gradient and line search. Results of computer simulations and real 3-D data show that the proposed algorithm converges much faster than the conventional EM and PCG for smooth edge-preserving regularization and can also be more efficient than the current state-of-art algorithms for the nonsmooth l(1) regularization.

关键词： Edge-preserving regularization image reconstruction optimization algorithm optimization transfer positron emission tomography (PET)

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Automatic image annotation using feature selection based on improving quantum particle swarm optimization

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SIGNAL PROCESSING 2015年 109卷 172-181页

作者： Jin, Cong Jin, Shu-Wei Cent China Normal Univ Sch Comp Sci Wuhan 430079 Peoples R China Ecole Normale Super Dept Phys F-75231 Paris 5 France

Automatic image annotation (AIA) is a task of assigning one or more semantic concepts to a given image and a promising way to achieve more effective image retrieval and analysis. It is a typical classification problem. Due to the semantic gap between low-level visual features and high-level image semantic, the performances of many existing image annotation algorithms are not satisfactory. This paper presents a novel AIA scheme based on improved quantum particle swarm optimization (IQPSO) algorithm for visual features selection (VFS) and an ensemble stratagem based on boosting technique to improve performance of image annotation approach. To maintain the population diversity, the measure method of population diversity and improvement operation are proposed. To achieve better performance of ALA scheme, the measure of population diversity is as a control condition of VFS process. The classification result of an ensemble classifier is as the final annotation result rather than individual classifier. The experimental results confirm that the proposed AIA scheme is very effectiveness. When using proposed AIA scheme over three image datasets respectively, the annotation results are satisfactory. (C) 2014 Elsevier B.V. All rights reserved.

关键词： Automatic image annotation Visual feature selection optimization algorithm Improvement operation Ensemble stratagem

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Binary optimization of metallic nano-tube-based absorption coefficient

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JOURNAL OF COMPUTATIONAL ELECTRONICS 2015年第2期14卷 486-491页

作者： Akhlaghi, Majid Shahmirzaee, Hosein Enjavi, Mohammad Hosain Islamic Azad Univ Omidieh Branch Young Researchers & Elite Club Omidieh Iran Univ Malek Ashtar Air Ocean Res Ctr Shiraz Iran Shiraz Univ Technol Shiraz Iran

A new efficient binary optimization method being established on teaching-learning-based optimization (TLBO) algorithm was used to design an array of plasmonic nano-tubes to increase maximum absorption coefficient spectrum. Binary TLBO (BTLBO), a bunch of learners including a matrix with binary entries responsible for controlling nano-tubes in the array, shows the presence with symbol of ('1') and the absence with ('0'). Simulation results indicate that non-periodic structure having more appropriate response in terms of the absorption coefficient strongly depends on the position of plasmonic nano-particles and non-periodic structures. This efficient approach is used in optical applications such as solar cell and plasmonic nano-antenna.

关键词： Word Optical engineering Plasmonic nanoparticles optimization algorithm

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