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Multiple enhancements of rate oscillations by non-Gaussian noise in NO reduction with CO on Pt(100)

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Science china Chemistry 2010年第1期53卷 226-230页

作者： GONG YuBing,XIE YanHang & HAO YingHang school of Physics and electronic engineering,ludong university,yantai 264025,china school of Physics and electronic engineering Ludong University Yantai China

The effect of the non-Gaussian colored noise(NGN) on the dynamics of nonlinear systems has attracted increasing *** work numerically studied the effect of a particular kind of the NGN,mainly in terms of its departure from Gaussian noise,on the rate oscillations(RO) in the catalytic reduction of NO with CO on Pt(100) *** was found that power spectrum density changes non-monotonically and the signal-to-noise ratio shows several peaks with increasing departure,demonstrating the presence of"departure-induced multiple resonance".Since the departure of the NGN determines the probability distribution and hence denotes the type of the noise,the phenomenon of"departure-induced multiple resonance"not only gives multiple enhancements of the RO by virtue of the departure of the NGN,but also implies that,besides Gaussian noise,various other types of noise may enhance the RO in the surface catalytic reaction systems.

关键词： non-Gaussian colored noise catalytic reduction of NO with CO on Pt(100) reaction rate oscillation coherence resonance

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2 1. school of Physics and electronic engineering, yantai Normal university, yantai 264025, china 2. Department of Physics, shandong Normal university, Jinan 250014, china school of Physics and electronic engineering Yantai Normal University Yantai China Department of Physics Shandong Normal University Jinan China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

Medical image segmentation using improved FCM

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Science china(Information Sciences) 2012年第5期55卷 1052-1061页

作者： ZHANG XiaoFeng 1,2,ZHANG CaiMing 1,3,4,TANG WenJing 1,2 & WEI ZhenWen 1 1 school of Computer Science and Technology,shandong university,Jinan 250101,china 2.school of Information and electrical engineering,ludong university,yantai 264025,china 3 school of Computer Science and Technology,shandong university of Finance and Economics,Jinan 250014,china 4 shandong Province Key Lab of Digital Media Technology,Jinan 250014,china school of Computer Science and Technology Shandong University Jinan China school of Information and electrical engineering Ludong University Yantai China school of Computer Science and Technology Shandong University of Finance and Economics Jinan China shandong Province Key Lab of Digital Media Technology Jinan China

Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more *** C-means,as an effective tool to deal with PVE,however,is faced with great challenges in *** at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two *** first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM *** with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying *** on medical images show that HisFCM can achieve good segmentation results in less than 0.1 second,and can satisfy real-time requirements of medical image processing.

关键词： FCM histogram image segmentation medical image processing

Relaxed delay-dependent exponential stability condition for a class of neural networks with polytopic uncertainties and distributed delays

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控制理论与应用（英文版） 2011年第2期9卷 302-306页

作者： Jianwei XIA 1,2,Hongbin ZHANG 3 1.school of Automation,Southeast university,Nanjing Jiangsu 210096,china 2.school of Mathematics Science,Liaocheng university,Liaocheng shandong 252000,china 3.school of electronic engineering,university of electronic Science and Technology,Chengdu Sichuan 610054,china school of Automation Southeast University Nanjing Jiangsu China school of Mathematics Science Liaocheng University Liaocheng Shandong China school of electronic engineering University of Electronic Science and Technology Chengdu Sichuan China

The global robust exponential stability of a class of neural networks with polytopic uncertainties and distributed delays is investigated in this ***-dependent Lypaunov-Krasovskii functionals and free-weighting matrices are employed to obtain sufficient condition that guarantee the robust global exponential stability of the equilibrium point of the considered neural *** derived sufficient condition is proposed in terms of a set of relaxed linear matrix inequalities (LMIs),which can be checked easily by recently developed algorithms solving LMIs.A numerical example is given to demonstrate the effectiveness of the proposed criteria.

关键词： Neural networks Polytopic uncertainties Distributed delays Delay-dependent Global robust exponential stability

The Design of Lens Imaging System byMeans of Fractional Fourier Transform

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Chinese Journal of Lasers 2002年第2期11卷 27-32页

作者： CHEN Jiannong XU Qiang (Department of Physics, yantai Teachers’ university, yantai 264025, china)D.R.Selviah(Department of electronic and electrical engineering, university College London, Torrington Place, London WC1E 7JE, UK) Department of Physics Yantai Teachers' University Yantai 264025 Department of electronic and electrical engineering University College London Torrington Place 英国 London WC1E 7JE

The relation between the 2nd fractional Fourier transform and the imaging process of an optical system is discussed. By changing the coordinate scales of the input plane in respect to the magnification of the optical imaging system, the fractional Fourier transform can be a powerful tool in designing specific imaging system. The Gaussian imaging formula of single lens is obtained by using the tool. Finally the procedures are generalized for designing a double-lens imaging system through an example.

关键词： lens imaging system fractional Fourier transform Gaussian imaging formula

Notifiable infectious disease surveillance with data collected by search engine

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Journal of Zhejiang university-Science C(Computers and electronics) 2010年第4期11卷 241-248页

作者： Xi-chuan ZHOU1,Hai-bin SHEN2 (1Department of Information Science and electronic engineering,Zhejiang university,Hangzhou 310027,china) (2school of electrical engineering,Zhejiang university,Hangzhou 310027,china) Department of Information Science and electronic engineering Zhejiang University Hangzhou China school of electrical engineering Zhejiang University Hangzhou China

Notifiable infectious diseases are a major public health concern in china,causing about five million illnesses and twelve thousand deaths every *** detection of disease activity,when followed by a rapid response,can reduce both social and medical impact of the *** aim to improve early detection by monitoring health-seeking behavior and disease-related news over the ***,we counted unique search queries submitted to the Baidu search engine in 2008 that contained disease-related search *** we counted the news articles aggregated by Baidu's robot programs that contained disease-related *** found that the search frequency data and the news count data both have distinct temporal association with disease *** adopted a linear model and used searches and news with 1–200-day lead time as explanatory variables to predict the number of infections and deaths attributable to four notifiable infectious diseases,i.e.,scarlet fever,dysentery,AIDS,and *** the search frequency data and news count data,our approach can quantitatively estimate up-to-date epidemic trends 10–40 days ahead of the release of Chinese Centers for Disease Control and Prevention(Chinese CDC)*** approach may provide an additional tool for notifiable infectious disease surveillance.

关键词： Notifiable infectious diseases Disease surveillance Search engine

Rate-oriented perceptual image coding using contrast-based quantization

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Chinese Optics Letters 2010年第4期8卷 381-383页

作者：余卫宇田菁 school of electronic and Information engineering South China University of Technology school of electrical and electronic engineering Nanyang Technological University

A new image coding approach is proposed by controlling the quantization step via minimizing the perceptual distortions（in terms of image＇s contrast measurement）.The proposed method is a rate-oriented contrast-based approach,which is in contrast to the conventional quality-oriented contrast-based image *** algorithm achieves a higher perceptual quality performance against several methods developed previously.

关键词： Visual communication

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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Science in china(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2, ZHANG LianMei3 & WANG Pu4 1 school of Computer and electronic engineering, Hunan university of Commerce, Changsha 410205, china 2.school of Information engineering, Xiangtan university, Xiangtan 411000, china 3 electrical engineering College, Wuhan university, Wuhan 430072, china 4 school of Commerce, Central South university, Changsha 410083, china school of Computer and electronic engineering Hunan University of Commerce Changsha China school of Information engineering Xiangtan University Xiangtan China electrical engineering College Wuhan University Wuhan China school of Commerce Central South University Changsha China

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. Experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

TiC/Fe cermet coating by plasma cladding using asphalt as a carbonaceous precursor

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Progress in Natural Science:Materials International 2008年第4期18卷 447-454页

作者： Junbo Liu school of Mechanical and electronic engineering, Weifang university, Weifang 261061, china school of Mechanical and electronic engineering Weifang University Weifang 261061 China

A new Ti-Fe-C compound powder for plasma cladding was prepared by heating a mixture powder of ferrotitanium and asphalt pyro-lyzed as a carbonaceous precursor. The carbon by the pyrolysis of the asphalt acts as a reactive constituent as well as a binder in the compound powder. The TiC/Fe cermet coatings were prepared by plasma cladding with the compound powder. Results show that the Ti-Fe-C compound powder has a very tight structure, which can avoid the problem of the reactive constituent particles being sep- arated during cladding. The TiC/Fe cermet coating presents a typical morphology of plasma cladding coatings with two different lam- inated layers:one is the composite layer in which the round fine TiC particles (2O3. The coating shows high hardness and excellent wear resistance. The surface hardness of the coating is 68 ± 5(HR30N). In the same fretting conditions, the wear area of Ni60 coating is about 11 times as much as the TiC/Fe cermet coating.

关键词： Plasma cladding TiC/Fe cermet coating Precursor Microstructure Wear resistance