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PSO-ACSC:a large-scale evolutionary algorithm for image matting

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Frontiers of Computer Science 2020年第6期14卷 31-42页

作者： Yihui LIANG han huang Zhaoquan CAI School of Computer Science University of Electronic Science and Technology of ChinaZhongshan InstituteZhongshan 528400China School of Software Engineering South China University of TechnologyGuangzhou 510006China Research Department Huizhou UniversityHuizhou 516007China

Image matting is an essential image processing technology due to its wide range of ***-based image matting is one of the main branches of image matting research that estimates alpha mattes by selecting the best pixel *** is essentially a large-scale multi-peak optimization problem of pixel *** study shows that particle swarm optimization(PSO)can effectively optimize the pixel ***,it still suffers from premature convergence problem which often occurs in pixel pair optimization that involves a large number of local *** address this problem,this work presents a parameter-free strategy for PSO called adaptive convergence speed controller(ACSC).ACSC monitors and conditionally controls the particles by competitive pixel pair recombination operator(CPPRO)and pixel pair reset operator(PPRO)during the *** performs CPPRO to improve the competitiveness of a particle when the performance of most of the pixel pairs is worse than that of the best-so-far *** is performed to avoid premature convergence when the alpha mattes regarding two selecleu particles ae liglly *** results show that ACSC significantly enhances the performance of PSO for image matting and provides competitive alpha mattes comparing with state-of-the-art evolutionary algorithms.

关键词： evolutionary computing particle swarm optimization large-scale optimization image matting

Recent advances in micro- and nano-machining technologies

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Frontiers of Mechanical Engineering 2017年第1期12卷 18-32页

作者： Shang GAO han huang School of Mechanical and Mining Engineering The University ofQueensland QLD 4072 Australia Key Laboratory for Precision andNon-traditional Machining Technology of Ministry of Education DalianUniversity of Technology Dalian 116024 China School of Mechanical and Mining Engineering The University ofQueensland QLD 4072 Australia

Device miniaturization is an emerging advanced technology in the 21 st century. The miniaturiza- tion of devices in different fields requires production of micro- and nano-scale components. The features of these components range from the sub-micron to a few hundred microns with high tolerance to many engineering materi- als. These fields mainly include optics, electronics, medicine, bio-technology, communications, and avionics. This paper reviewed the recent advances in micro- and nano-machining technologies, including micro-cutting, micro-electrical-discharge machining, laser micro-machin- ing, and focused ion beam machining. The four machining technologies were also compared in terms of machining efficiency, workpiece materials being machined, minimum feature size, maximum aspect ratio, and surface finish.

关键词： micro machining cutting electro dischargemachining (EDM) laser machining focused ion beam(FIB)

Deformation, failure and removal mechanisms of thin film structures in abrasive machining

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Advances in Manufacturing 2017年第1期5卷 1-19页

作者： Cheng-Wei Kang han huang School of Mechanical and Mining Engineering TheUniversity of Queensland Brisbane QLD 4072 Australia

Thin film structures are becoming increasingly more important for industrial applications such as the making of solar panels, microelectronic devices and micro systems. However, the challenges encountered in the machining of thin film structures have been a bottleneck that impedes further wide spread uses of such structures. The development of material removal processes that are capable of producing a damage free surface at high removal rates is critical for cost effective production. Such development relies highly on a comprehensive understanding of the deformation, failure and removal mechanisms of thin film structures involved in mechanical loading. In this paper, the current understanding of the deformation characteristics of thin film systems was reviewed to provide important insights into the interracial failure under mechanical loading, with focuses on the interfacial failure mechanisms and existing problems in the machining of thin film structures. The key characterization techniques were outlined. In particular, the recent progress in the abrasive machining of a thin film multilayer structure was summarized. The potential research directions were also presented in the end of the review.

关键词： Abrasive machining Thin film Bilayer Multilayer Interface Deformation Failure

Laser stealth absorbent of samarium oxysulfide prepared by flux method

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Rare Metals 2011年第6期30卷 616-620页

作者： han Pengde huang Xiaogu ZhanG Qitu College of Materials Science and Engineering Nanjing University of Technology Nanjing 210009 China

A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition, morphology, and reflectivity of the powders were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and ultraviolet-visible spectrophotometer （UVPC）. The results showed that pure phase of Sm202S could be obtained with Na2CO3 as flux above 950~C, and the reflectivity decreased with the calcination temperature increasing. Compared with other samarium compounds, the reflectivity at 1064 nm of Sm2O2S was the lowest. Different fluxes had great impact on the phase composition, particle morphology, and reflectivity of the products. In short, Sm2O2S was suitable as a kind of absorbent against 1064 nm laser.

关键词： laser stealth samarium oxysulfide flux reflectivity

Widening and weakening of the Hadley circulation under global warming

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Science Bulletin 2018年第10期63卷 640-644页

作者： Yongyun Hu han huang Chen Zhou Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University School of Atmospheric Sciences Nanjing University

The Hadley circulation is one of the most important atmospheric *** of the Hadley circulation has drawn extensive studies in the past *** key concern is that widening of the Hadley circulation would cause poleward shift of the subtropical dry *** metrics have been applied to measure the widening of the *** are responsible for the observed widening trends of the Hadley circulation? How anthropogenic and natural forcings caused the widening? How the widening results in regional climatic effects? These are the major questions in studing the widening of the Hadley *** both observations and simulations all show widening of the Hadley circulation in the past few decades,there are no general agreements of changes in the strength of the Hadley *** some reanalysis datasets show strengthening of the Hadley circulation,it was shown that the strengthening trend could be artificial,and simulations show weakening of the Hadley circulation for global greenhouse *** the present paper,we shall briefly review the major progresses of studies in trends in width and strength of the Hadley *** address answers to these questions,clarify inconsistent results,and propose ideas for future studies.

关键词： Hadley circulation Greenhouse gases Ozone depletion ENSO Global warming

Reducing subspaces of multiplication operators on function spaces

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Applied Mathematics(A Journal of Chinese Universities) 2013年第4期28卷 395-404页

作者： GUO Kun-yu huang han-song School of Mathematical Sciences Fudan University Department of Mathematics East China University of Science and Technology

This survey presents the brief history and recent development on commutants and reducing subspaces of multiplication operators on both the Hardy space and the Bergman space, and von Neumann algebras generated by multi... 详细信息

关键词： reducing subspace commutant von Neumann algebra Blaschke product holomorphic covering map

Theoretical analysis of the convergence property of a basic pigeon-inspired optimizer in a continuous search space

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Science China(Information Sciences) 2019年第7期62卷 90-98页

作者： Yushan ZhanG han huang Hongyue WU Zhifeng HAO School of Statistics and Mathematics Guangdong University of Finance and Economics Big Data and Educational Statistics Application Laboratory Guangdong University of Finance and Economics School of Software Engineering South China University of Technology School of Mathematics and Big Data Foshan University

The pigeon-inspired optimization(PIO) algorithm is a newly presented swarm intelligence optimization algorithm inspired by the homing behavior of pigeons. Although PIO has demonstrated effectiveness and superiority in numerous fields, particularly in practical engineering optimization, there have been few results concerning the theoretical foundations of PIO. This paper conducts convergence analysis of basic PIO in a continuous search space in two aspects. First, we analyze the convergence of each pigeon’s expected position using a difference equation and prove that the average position of each pigeon in the swarm will converge to the same value. To further study the stochastic global convergence property of the pigeon swarm, we apply the martingale theory to investigate the basic PIO swarm sequence, and achieve a sufficient condition to guarantee global convergence of the basic PIO. Our theoretical analysis shows that this convergence depends upon the accumulation of the minimum probability with which the pigeon swarm jumps to the global-optimal region at each iteration. The mathematical methods proposed in this study, particularly the martingale technique, also provide a new effective approach for the theoretical analysis of bio-inspired algorithms in continuous optimization.

关键词： pigeon-inspired optimization(PIO) convergence analysis martingale continuous optimization swarm intelligence

Determining node duty cycle using Q-learning and linear regression for WSN

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Frontiers of Computer Science 2021年第1期15卷 17-23页

作者： han Yao huang Kyung Tae KIM Hee Yong YOUN College of Software Sungkyunkwan UniversitySuwon 440-746Korea

Wireless sensor network(WSN)is effective for monitoring the target environment,which consists of a large number of sensor nodes of limited *** efficient medium access control(MAC)protocol is thus imperative to maximize the energy efficiency and performance of *** most existing MAC protocols are based on the scheduling of sleep and active period of the nodes,and do not consider the relationship between the load condition and *** this paper a novel scheme is proposed to properly determine the duty cycle of the WSN nodes according to the load,which employs the Q-leaming technique and function approximation with linear *** allows low-latency energy-efficient scheduling for a wide range of traffic conditions,and effectively overcomes the limitation of Q-learning with the problem of continuous state-action ***3 simulation reveals that the proposed scheme significantly improves the throughput,latency,and energy efficiency compared to the existing fully active scheme and S-MAC.

关键词： wireless sensor network media access control duty-cycle scheduling Q-leaming linear regression

THE RELATIONSHIP BETWEEN PROJECTIVE GEOMETRIC AND RATIONAL QUADRATIC B-SPLINE CURVES

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Applied Mathematics(A Journal of Chinese Universities) 1998年第4期13卷 445-450页

作者： han XI’AN AND huang XILI Department of Basic Theories Institute of Command and Technology

Abstract For two rational quadratic B spline curves with same control vertexes, the cross ratio of four collinear points are represented: which are any one of the vertexes, and the two points that the ray initialing from the vertex intersects with the corresponding segments of the two curves, and the point the ray intersecting with the connecting line between the two neighboring vertexes. Different from rational quadratic Bézier curves, the value is generally related with the location of the ray, and the necessary and sufficient condition of the ratio being independent of the ray's location is showed. Also another cross ratio of the following four collinear points are suggested, i.e. one vertex, the points that the ray from the initial vertex intersects respectively with the curve segment, the line connecting the segments end points, and the line connecting the two neighboring vertexes. This cross ratio is concerned only with the ray's location, but not with the weights of the curve. Furthermore, the cross ratio is projective invariant under the projective transformation between the two segments.

关键词： Computer aided geometric design rational B-spline curve cross ratio weight