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Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1.2, TANG Jun 2 , ZHANG AiHua 3 & JIA Ya 2 1.department of Physics, Lanzhou {1. of Technology, Lanzhou 730050, china 2 department of Physics, Central china Normal {1., Wuhan 430079, china 3 College of Electrical and information engineering, Lanzhou {1. of Technology, Lanzhou 730050, china 1. department of Physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

A relationship between the nonexistence of generalized bent functions and class groups

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Science china Mathematics 2010年第1期53卷 213-222页

作者： LIU FengMei 1.& YUE Qin 21.department of {1. Research,College of {1. engineering,{1. engineering university,Zhengzhou 450002,china 2 department of Mathematics,Nanjing university of Aeronautics and Astronautics,Nanjing 21.01.,china 1. department of {1. Research College of Information Engineering Information Engineering University Zhengzhou 450002 China2. Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new result on the nonexistence of generalized bent functions is presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the parameters in our results.

关键词： generalized bent function integral basis class group genus theory

Seamlet carving for shape-aware image resizing

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Science china({1. Sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1.2,SHENG Bin 1.MA LiZhuang 1.SHEN Yang 1.& CHEN ZhiHua 3 1.department of Computer Science and {1.,Shanghai Jiao Tong university,Shanghai 200240,china 2 Academy of information Technology,Luoyang Normal university,Luoyang 471.22,china 3 department of Computer Science and {1.,East china university of Science and Technology,Shanghai 200237,china 1. department of Computer Science and {1. Shanghai Jiao Tong University Shanghai 200240 China2. Academy of Information Technology Luoyang Normal University Luoyang 471022 China3. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1. the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1. 2, ZHANG Yin-ling1. 2, WANG Fei 1.,2, ZHANG Zhen-hui 3, GUO Yu-xiang1. 2 1. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic {1., Jiaozuo 454003, china 2. School of Surveying and land information engineering, Henan Polytechnic {1., Jiaozuo 454003, china 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 266041. china Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

Conditions on converting coherence into entanglement

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Chinese Physics B 2017年第8期26卷 46-49页

作者：杨连武夏云杰 Shandong Provincial Key Laboratory of Laser Polarization and information Technology Department of PhysicsQufu Normal University department of Physics and {1. engineering Jining University

The present studies show that any nonzero amount of coherence of a system can be converted into entanglement between the system and an incoherent ancillary system via incoherent operations. According to this conclusion, we study the process of converting coherence into entanglement via a unitary operation where the initial ancillary system is of different quantum state. We find that some other conditions should be satisfied in converting coherence into entanglement. We also study the conditions of coherence consumption of converting coherence into entanglement.

关键词： coherence entanglement conditions

Truncation error calculation based on Richardson extrapolation for variable-step collaborative simulation

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Science china({1. Sciences) 2011年第6期54卷 1238-1250页

作者： ZHANG HeMing 1., LIANG SiLu 2 , SONG ShiJi 1.& WANG HongWei 3 1.department of Automation, TNList, Tsinghua {1., Beijing 1.0084, china 2 Computer and information Management Center, Tsinghua {1. Beijing 1.0084, china 3 engineering Design Centre, engineering department, Cambridge {1., Cambridge CB2 1.Z, UK 1. department of Automation TNList Tsinghua University Beijing 100084 China2. Computer and Information Management Center Tsinghua University Beijing 100084 China3. Engineering Design Centre Engineering Department Cambridge University Cambridge CB2 1PZ UK

Collaborative simulation is an effective approach to performing simulation analysis for complex systems by integrating models developed for different engineering disciplines. Collaborative simulation issues include the modeling of coupled multidisciplinary systems, and the simulation running time integration of these models that are solved parallelly. Estimation of the local truncation error of coupling models is the key to solve multidisciplinary collaborative simulation problem, which is actually used to restrict the simulation step. This paper presents a variable-step method based on Richardson extrapolation for calculating the local truncation error to solve collaborative simulation problem of multidisciplinary coupling models. Formulas for estimating the local truncation error are derived through theoretical analysis by using integration methods and interpolation technologies, respectively. The simulation experiments are illustrated to validate the accuracy and efficiency of proposed collaborative simulation algorithm in comparison with the usual combinative algorithm.

关键词： multidisciplinary systems collaborative simulation variable-step algorithm error estimation

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural Science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1.*, WANG Yingwei2, FENG Zhijing1.and CHENG Kai3(1. State Key Laboratory of Tribiology, Tsinghua university, Beijing 1.0084,{1. 2. department of Material Sciences, Changchun university of Science and Technology, Changchun 1.0021.{1. 3. Faculty of information and engineering Systems, City Campus, Leeds LS1.3HE, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China department of Material Sciences Changchun University of Science and Technology Changchun 130021 China Faculty of information and {1. Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 1..98 nm reaches 1.22 nm root mean square (RMS) after 20 min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china({1. Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2 & FENG GuangZeng3 1department of Electronic and information engineering, Zhejiang Institute of Media and Communications, Hangzhou 310018, china 2department of information engineering, Jiangsu City Vocation College, Nanjing 210036, china 3College of Communication and information engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, china 1. department of Electronic and {1. engineering Zhejiang Institute of Media and Communications Hangzhou 310018 China2. Department of Information Engineering Jiangsu City Vocation College Nanjing 210036 China3. College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding

Improved performance of GaN-based light-emitting diodes by using short-period superlattice structures

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Progress in Natural Science:Materials International 2010年第1期20卷 70-75页

作者： Yi-jung LIU~1.Chien-chang HUANG~1.Tai-you CHEN~1.Chi-shiang HSU~1.Shiou-ying CHENG~2, Kun-wei LIN~3,Jian-kai LIOU~1.Wen-chau LIU~1.1.Institute of Microelectronics,department of Electrical {1.,National Cheng-Kung university, Tainan 701.1.Taiwan,china 2.department of Electronic {1.,Nation Ilan university,I-Lan 26041.Taiwan,china 3.department and Graduate Institute of Computer Science and information {1., Chaoyang university of Technology,Taichung 41.49,Taiwan,china [a] Institute of Microelectronics Department of Electrical Engineering National Cheng-Kung University Tainan 70101 Taiwan China [b] department of Electronic {1. Nation Ilan University I-Lan 26041 Taiwan China [c] department and Graduate Institute of Computer Science and {1. engineering Chaoyang University of Technology Taichung 41349 Taiwan China

An InGaN/GaN multiple-quantum-well（MQW）light-emitting diode（LED）with a ten-period i（undoped）-InGaN/p（Mg doped）-GaN（2.5 nm/5.0 nm）superlattice（SL）structure,was *** SL structure that can be regarded as a confinement layer of holes to enhance the hole injection efficiency is inserted between MQW and p-GaN *** studied LED device exhibits better current spreading performance and an improved quality,compared with a conventional one without SL *** to the reduced contact resistance as well as more uniformity of carriers injection,the operation voltage at 20 mA is decreased from 3.32 to 3.1. V.A remarkably reduced reverse-biased leakage current(1.-7-1.-9A)and higher endurance of the reverse current pulse are *** measured output power and external quantum efficiency（EQE）of the studied LED are 1..6 mW and 24.8%,respectively. In addition,significant enhancement of 25.4%in output power as well as increment of 5%in EQE for the studied devices is observed, as the studied devices show superior current spreading ability and reduction in dislocations offered by the SL structure.

关键词： GaN superlattice(SL) current spreading hole confinement electrostatic discharge(ESD)