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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

Giant magnetoimpedance effect of multilayered structure(F/SiO_2)_3/Ag/(SiO_2/F)_3 films deposited in a longitudinal magnetic field

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Science China(Technological Sciences) 2010年第3期53卷 287-292页

作者： CHEN WeiPing1,2,SHAO XianYi1,2,FENG ShangShen1,2,XIAO ShuQin3 & LIU YiHua3 1 school of Physics and electronics Engineering,Zhejiang Taizhou University,Taizhou 318000,China 2 Institute of Function Materials for Electronic information,Zhejiang Taizhou University,Taizhou 318000,China 3 school of Physics,Shandong University,Jinan 25.100,China 1. school of Physics and electronics Engineering Zhejiang Taizhou University Taizhou 318000 China2. Institute of Function Materials for Electronic Information Zhejiang Taizhou University Taizhou 318000 China3. School of Physics Shandong University Jinan 250100 China

The soft magnetic properties and giant magnetoimpedance(GMI) effect of the multilayered structure(F/SiO2)3/Ag/(SiO2/F)3(F≡Fe71.5.u1Cr2.5.4Si12B9) films,which were prepared by radio frequency sputtering without and with a longitudinal magnetic field of about 72 kA/m,are *** results show that the GMI effect almost cannot be detected in the samples deposited without field,whereas,a longitudinal magnetic field applied during deposition process obviously optimizes the soft magnetic properties of the films,and noticeable GMI effect is *** maximum values of the longitudinal and transverse GMI ratios are 45. and 44% at the frequency of 6.81 MHz,*** addition,the dependence of magnetoimpedance ratio,magnetoresistance ratio,magnetoreactance ratio and effective permeability ratio on the frequency has been *** found that the GMI spectrum curves in the longitudinal and transverse cases almost overlap for the field-deposited *** GMI effect is mainly a giant magnetoinductive effect at low *** f >9 MHz,magnetoreactance ratio changes to a negative,i.e.,the property of reactance changes from inductive to capacitive.

关键词： Fe-based soft magnetic alloy as-deposited multilayered films giant magnetoimpedance effect effective permeability magnetic anisotropy

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Nonparametric Model Learning Adaptive Control Method of DC Motor

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Nonparametric Model Learning Adaptive Control Method of DC M...

Enhanced Fisheye State Routing Using Cross-layer Optimization

2009中国控制与决策会议

作者： Cao Rongmin~1,Hou Zhongsheng~2,Bai Lianping~1 1.school of Automation,Beijing information Science & Technology University,Beijing 100192,China 2.school of electronics and information Engineering,Beijing Jiaotong University,Beijing 100044,China

＜正＞Nonparametric model learning adaptive control method（NMLAC） presented in this paper is based on new concepts called pseudo-partial-derivatives（PPD） for a class of nonlinear *** structural information,no mathematical model,no training process and no external testing signals are *** unmodelled dynamics do not *** this paper,nonparametric model learning adaptive control（NMLAC） approach of a class of SISO nonlinear discrete-time systems based on linearization of tight format is applied to DC motor rotate speed *** design of controller is model-free,based directly on pseudo-partial-derivatives（PPD） derived on-line from the input and output information of the motor motion model using novel parameter estimation *** experiment examples are provided for real nonlinear systems,which are known to be difficult to model,and control to demonstrate the correctness,effectiveness and advantages of the approaches proposed.

关键词： computer simulation DC motor NMLAC nonlinear systems and stability

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Enhanced Fisheye State Routing Using Cross-layer Optimizatio...

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

2009中国控制与决策会议

作者： Lianggui Liu~1,Zhixin Chen~2 1.school of Informatics & electronics,Zhejiang Sci-Tech University,Hangzhou 310018,China 2.school of information,Central University of Finance and Economics,Beijing 100081,China

＜正＞An enhanced fisheye state routing using cross-layer optimization was ***-FSR synthetically considers the state of MAC and network layer synthetically,adopts cross-layer technology to balance network traffic while supporting QoS better and achieving better network *** CO-FSR,the node that has worse traffic load state will not be selected to forward data packets even though it is on the shortest（that is,the number of hops is the smallest） path between source-destination *** results shows that CO-FSR can decrease average end-to-end delay and increase throughput especially when the network has more offered ***-FSR inherits the merit of FSR such as simple,efficient and scalable etc while taking into account cross-layer *** CO-FSR proves to be a more efficient solution to the routing problem in large mobile ad hoc networks.

关键词： Cross-layer Fisheye State Routing ad hoc networks

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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 315.11, China 2. The school of Microelectronics and Solid-state electronics, University of Electronic Science and Tech-nology of China, Chengdu 61005., China 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830022, China 4. Hongtak (Chengdu) Electronic Co., Ltd, Chengdu 610041, China 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 (135.°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (145.°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 15. 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.

On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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Science in China(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2, 3 , FU Yuli 4 & XIE Shengli 4 1. Department of Control Science & Control Engineering, Huazhong University of Science & Technology, Wuhan 430074, China 2. school of Automation, Wuhan University of Science & Technology, Wuhan 430070, China 3. school of information, Central South University of Economy, Politics and Law, Wuhan 430064, China 4. school of electronics & information Engineering, South China University of Technology, Guangzhou 5.0640, China Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) 1. Department of Control Science & Control Engineering Huazhong University of Science & Technology 430074 Wuhan China 2. school of Automation Wuhan University of Science & Technology 430070 Wuhan China 3. school of information Central South University of Economy Politics and Law 430064 Wuhan China 4. school of electronics & information Engineering South China University of Technology 510640 Guangzhou China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

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转辙机动作杆中光纤应力传感器的研究

铁道学报 2004年第6期26卷 120-122页

作者：孙强周虚北京交通大学电子信息工程学院北京100044 北京邮电大学电信工程学院北京100876

研究了非对称刻蚀光纤应力传感器的基本原理,将其应用在转辙机中,为转辙机动作杆应力的检测提供了一种新的测试方法。

关键词：光纤传感器转辙机动作杆应力

A conjecture on k-factor-critical and 3-γ-critical graphs

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Science China Mathematics 2010年第5期53卷 348-354页

作者： WANG Tao1&YU QingLin2 1Institute of Applied Mathematics,College of Mathematics and information Science,Henan University,Kaifeng 475.01,China 2Department of Mathematics and Statistics,Thompson Rivers University,Kamloops,BC V2C5.3,Canada 1. Institute of Applied Mathematics College of Mathematics and Information Science Henan University Kaifeng 475001 China2. Department of Mathematics and Statistics Thompson Rivers University Kamloops BC V2C5N3 Canada

For a graph G =(V,E),a subset VS is a dominating set if every vertex in V is either in S or is adjacent to a vertex in *** domination number γ(G) of G is the minimum order of a dominating set in G.A graph G is said to be domination vertex critical,if γ(G-v) 2 and k≡|V|(mod 2).If G is 3-γ-edge-critical and claw-free,then G is *** this paper we present a proof to this conjecture,and we also discuss the properties such as connectivity and bicriticality in 3-γ-vertex-critical claw-free graph.

关键词： domination critical graph factor critical bicritical

Calculation of triaxial superdeformation in ^(174)Hf

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 553-557页

作者： YU ShaoYing1,2,4, LI XiaoWei2, SHEN CaiWan1,5.& CHEN YongShou3,4 1 school of Science, Huzhou Teachers College, Huzhou 313000, China 2 College of Mathematics, Physics and information Engineering, Zhejiang Normal University, Jinhua 321000, China 3 China Institute of Atomic Energy, Beijing 102413, China 4 Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China 5.Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, China 1. school of Science Huzhou Teachers College Huzhou 313000 China 2. College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321000 China 4. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China 5. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China 3. China Institute of Atomic Energy Beijing 102413 China

A two-dimensional Total Routhian Surface (TRS) calculation with the fixed hexa- decapole deformation ε4 = 0.03 was carried out for several configurations of 174Hf. Results indicate that the shell corrections have an important contribution to the formation of triaxial superdeformation in 174Hf and some possible configuration assignments are made to the 4 TSD bands experimentally found in 174Hf.

关键词： Total Routhian Surface (TRS), triaxial superdeformation, configuration