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A computer simulation of nucleation and growth of thin films

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science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3 1. Key Laboratory of Opto-electronic technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong {2., Lanzhou 730070, china 2. school of Physical science and technology, Lanzhou {2., Lanzhou 730000, china 3. school of Chemistry and Chemistry Engineering, Lanzhou {2., Lanzhou 730000, china 1. Key Laboratory of Opto-electronic technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University 730070 Lanzhou China 2. school of Physical science and technology Lanzhou University 730000 Lanzhou China 3. school of Chemistry and Chemistry Engineering Lanzhou University 730000 Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Accountability Analysis of electronic Commerce Protocols by Finite Automaton Model

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Wuhan university Journal of Natural sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2., Zhang Huan-guo 1 1. school of computer, Wuhan {2., Wuhan 430072. Hubei, china 2. Institute of Network technology, Guizhou {2. of technology, Guiyang 550003, Guizhou, china Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Guizhou university of technology Institute of Network Technology Guiyang Guizhou China (GRID:grid.443382.a) (ISNI:***) Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: supported by the National Natural science Foundation of china (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952.), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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science china(Information sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2.& LONG KePing2.1 Research center for Optical Internet and Mobile Information Networks(COIMIN),university of {2. science and technology of china,chengdu 6.1731,china 2.school of computer and Communications Engineering,university of science and technology Beijing,Beijing 100083,china 1. Research center for Optical Internet and Mobile Information Networks (COIMIN) University of Electronic Science and Technology of China Chengdu 611731 China2. School of Computer and Communications Engineering University of Science and Technology Beijing Beijing 100083 China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(sFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed sFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

A new approach based on PsO algorithm to find good computational encoding sequences

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Progress in Natural science:Materials International 2007年第6期17卷 712-716页

作者： Cui Guangzhao1, Niu Yunyun1, Wang Yanfeng1, Zhang Xuncai2.and Pan Linqiang2.1. school of Electrical and electronic Engineering, Zhengzhou {2. of Light Industry, Zhengzhou 450002. china 2. Research Institute of Biomolecular computer, Huazhong {2. of science and technology, Wuhan 430074, china) [a]school of Electrical and electronic Engineering Zhengzhou University of Light Industry Zhengzhou China [b]Research Institute of Biomolecular computer Huazhong University of Scienc and Technology Wuhan China

Computational encoding DNA sequence design is one of the most important steps in molecular computation. A lot of research work has been done to design reliable sequence library. A revised method based on the support system developed by Tanaka et al. is proposed here with different criteria to construct fitness function. Then we adapt particle swarm optimization (PsO) algorithm to our encoding problem. By using the new algorithm, a set of sequences with good quality is generated. The result also shows that our PsO-based approach could rapidly converge at the minimum level for an output of the simulation model. The celerity of the algorithm fits our requirements.

关键词： DNA computing computational encoding DNA sequences PsO algorithm fitness function

Fast parallel algorithms for discrete Gabor expansion and transform based on multirate filtering

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science china(Information sciences) 2012年第2期55卷 293-300页

作者： TAO Liang1 & GU JuanJuan2.1school of computer science and {2.,Anhui university,Hefei 2.0039,china 2.epartment of electronic Information and Electrical Engineering,Hefei university,Hefei 2.002.,china 1. school of computer science and {2. Anhui University Hefei 230039 China2. Department of Electronic Information and Electrical Engineering Hefei University Hefei 230022 China

The Gabor transform has long been recognized as a very useful tool for the joint time and frequency analysis in signal *** real time applications,however,were limited due to the high computational complexity of the Gabor transform *** this paper,some novel and fast parallel algorithms for the finite discrete Gabor expansion and transform are presented based on multirate *** analysis filter bank is designed for the finite discrete Gabor transform(DGT)and a synthesis filter bank is designed for the finite discrete Gabor expansion(DGE).Each of the parallel channels in the two filter banks has a unified structure and can apply the FFT and the IFFT to reduce its computational *** computational complexity of each parallel channel does not change as the oversampling rate *** fact,it is very low and depends only on the length of the input discrete signal and the number of the Gabor frequency sampling *** computational complexity of the proposed parallel algorithms is analyzed and compared with that of the major existing parallel algorithms for the finite DGT and *** results indicate that the proposed parallel algorithms for the finite DGT and DGE based on multirate filtering are very attractive for real time signal processing.

关键词： discrete Gabor expansion discrete Gabor transform critical sampling and oversampling multirate filtering analysis and synthesis filter banks

Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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science china(Technological sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2. CHANG Aimin3, YANG Bangchao2.& ZHANG Yikang4 1. The school of Information science Engineering, Ningbo university, Ningbo 3152.1, {2. 2. The school of Microelectronics and solid-state electronics, university of electronic science and Tech-nology of {2., chengdu 610054, {2. 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of sciences, Urumqi 83002., {2. 4. Hongtak (chengdu) electronic Co., Ltd, chengdu 610041, {2. Correspondence should be addressed to Jian Jiawen 1. The school of Information science Engineering Ningbo University 315211 Ningbo China 2. The school of Microelectronics and solid-state electronics University of Electronic Science and Technology of China 610054 Chengdu China 3. The Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences 830022 Urumqi China 4. Hongtak (chengdu) electronic Co. Ltd 610041 Chengdu China

spark-plasma sintering (sPs) process was used to sinter ZrO2.(8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (1450°C 4 h)(Cs). By the X-ray diffraction (XRD) patterns, the microstructure of the sPs pellet and Cs pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the sPs pellet is 154 nm and D111 of the Cs pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of sPs pellet is different from that of Cs pellet. The activation energy for the sPs ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol?1, which is in good agreement with Cs pellet (96 kJ mol?1), indicating that the conduction mechanism in sPs ceramics is similar to that in Cs ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.

study on An Absolute Non-Collision Hash and Jumping Table IP Classification Algorithms

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Wuhan university Journal of Natural sciences 2004年第5期9卷 835-838页

作者： sHANG Feng-jun 1,2.,PAN Ying-jun 1 1. Key Laboratory of Opto-electronic technology and system of Ministry of Education/College of Opto-electronic Engineering,Chongqing university, Chongqing 400044,china 2. College of computer science and technology, Chongqing university of Posts and Telecommunications, Chongqing 400065,china Chongqing university Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic Engineering Chongqing China (GRID:grid.190737.b) (ISNI:***) Chongqing university of Posts and Telecommunications College of Computer Science and Technology Chongqing China (GRID:grid.411587.e) (ISNI:***) Chongqing university Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic Engineering Chongqing China (GRID:grid.190737.b) (ISNI:***)

In order to classify packet, we propose a novel IP classification based the non-collision hash and jumping table trie-tree (NHJTTT) algorithm, which is based on noncollision hash Trie-tree and Lakshman and stiliadis proposing a 2.dimensional classification algorithm (Ls algorithm). The core of algorithm consists of two parts: structure the non-collision hash function, which is constructed mainly based on destination/source port and protocol type field so that the hash function can avoid space explosion problem; introduce jumping table Trie-tree based Ls algorithm in order to reduce time complexity. The test results show that the classification rate of NHJTTT algorithm is up to 1 million packets per second and the maximum memory consumed is 9 MB for 10 000 rules. Key words IP classification - lookup algorithm - trie-tree - non-collision hash - jumping table CLC number TN 393.06 Foundation item: supported by the Chongqing of Posts and Telecommunications Younger Teacher Fundation (A2.03-03).Biography: sHANG Feng-jun (1972.), male, Ph.D. candidate, lecture, research direction: the smart instrument and network.

关键词： IP classification lookup algorithm trie-tree non-collision hash jumping table

Electrochemical Characterization of surface-modified LiMn_2._4 Cathode Materials for Li-ion Batteries

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Journal of Wuhan university of technology(Materials science) 2006年第4期21卷 56-59页

作者：禹筱元 College of science South China Agricultural University Guangzhou 510642ChinaSchool of Physics & Engineering Sun Yat-sen University Guangzhou 510275China

To improve the performance, the surface of 12.n2.4 was coated with very fine MgO , Al2.3 and ZnO by solgel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction （ XRD ）, X-ray photoelectron spectroscopy （ XPs ） and scanning electron microscopy （sEM）. The charge and discharge performance of uncoated and surfnce modified 12.n2.4 spinel at 2.℃ and 55 ℃ were tested, using a voltage window of 3.0-4.35 V and a current deasity of 0. 1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated UMn2.O4, bat the cycle ability of 12.12.n2.4 coated by metal-oxide has remarkably been improved. The EIs measuremeuts of uncoated and Al2.3 -coated 12.n2.4 were carried out by a model 2.3 A potentiostatl galvanistat controUed by a computer using M2.0 software, and using a freqnency response analyzer （ Zsimpwin ） combined with a potentiostate （ PAR 2.3）. Coaseqnently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn , which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of 12.n2.4 cathode material for lithium batteries.

关键词： lithium-ion batteries surface modification metal-oxide coating: 12.n2.4 cathode

A self-calibration algorithm for cross array in the presence of mutual coupling

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science china(Information sciences) 2011年第4期54卷 836-848页

作者： HU XiaoQin 1,2.CHEN Hui 2.WANG YongLiang 2.& CHEN JianWen 2.1 College of electronic science and Engineering,National university of Defense {2.,Changsha 410073,china 2.Key Lab of Wuhan Radar Academy,Wuhan 430019,china 1. College of electronic science and Engineering National University of Defense Technology Changsha 410073 China2. Key Lab of Wuhan Radar Academy Wuhan 430019 China

In this paper,a novel blind mutual coupling self-calibration algorithm especially tailored to cross array is *** method compensates for the mutual coupling not only between sensors in each subarray but also between two *** the property of coupling matrix,the proposed method requires neither the calibration sources in known locations nor the multidimensional nonlinear *** method can jointly estimate the DOAs of the incoming signals and the unknown mutual coupling coefficients,and has high estimation precision and low computational *** analysis and computer simulations show the effectiveness of the proposed algorithm.

关键词： cross array mutual coupling self-calibration DOA estimation