检索结果-南通市图书馆

Notifiable infectious disease surveillance with data collected by search engine

在线全文

学校读者我要写书评

暂无评论

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,{2.,China) (2.chool of Electrical Engineering,zhejiang university,{2.,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 2.08 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 1–2.0-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

The Cauchy Integral Operator on Weighted Hardy Space

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2010年第4期31卷 461-472页

作者： Jianmiao RUAN Jiecheng CHEN Department of mathematics Zhejiang University Hangzhou 310027 China Department of mathematics Zhejiang Education Institute Hangzhou 310012 China

The authors show that the Cauchy integral operator is bounded from Hωp(R1) to hωp(R1) (the weighted local Hardy space). To prove the results, a kind of generalized atoms is introduced and a variant of weighted "Tb t... 详细信息

关键词： Cauchy integral Calder6n-Zygmund operator Weighted Hardy space Weighted local Hardy space

On Holomorphic Automorphisms of a Class of Non-homogeneous Rigid Hypersurfaces in C^(N+1)

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2010年第2期31卷 201-210页

作者： Qingyan WU Department of mathematics,Linyi Normal {2.,Linyi 2.6005,Shandong,China Department of mathematics,zhejiang university,hangzhou 31002.,China Department of mathematics Linyi Normal University Linyi 276005 Shandong China Department of mathematics Zhejiang University Hangzhou 310027 China

The author determines the real-analytic infinitesimal CR automorphisms of a class of non-homogeneous rigid hypersurfaces in CN+1 near the origin,and the connected component containing the identity transformation of al... 详细信息

关键词： Real-analytic infinitesimal CR automorphisms Rigid hypersurfaces Holomorphic automorphisms

Rotationally symmetric translating soliton of H^k-flow

在线全文

学校读者我要写书评

暂无评论

Science China mathematics 2010年第4期53卷 1011-1016页

作者： SHENG WeiMin & WU Chao Department of mathematics,{2.,hangzhou 31002.,China 1. Department of mathematics Zhejiang University Hangzhou 310027 China

This paper mainly considers the translating soliton of H k-flow for k > *** give the asymptotic expression of the entire rotationally symmetric translating soliton,and obtain non-convex 'Wing-like' solution as well as... 详细信息

关键词： H k-flow translating soliton 'Wing-like' solution

Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅱ:Results and Discussion

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2012年第1期25卷 81-87页

作者： CHEN Wenhua1,2.MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2.1 Institute of Mechanical Design,zhejiang university,hangzhou 31002.,China 2.Institute of Mechanical Design and Manufacturing,{2. Sci-Tech university,hangzhou 310018,China 3 State Testing Laboratory of hangzhou Bearing Test & Research Center,hangzhou 31002.,China 1. Institute of Mechanical Design Zhejiang University Hangzhou 310027 China 2. Institute of Mechanical Design and Manufacturing Zhejiang Sci-Tech University Hangzhou 310018 China 3. State Testing Laboratory of hangzhou Bearing Test & Research Center Hangzhou 310022 China

Ball bearings are widely employed mechanical components characterized by high precision and quality,and usually play important roles in various rotary machines and *** advanced applications require a deep understanding of their various kinematic and tribological characteristics that are essential to predict the fatigue endurance,relieve the vibration and minimize the power dissipation of ball bearings in particular *** angular contact ball bearing under a specified operating condition is simulated with the quasi-static/creepage analytical model proposed in the preceding *** results demonstrate that the ball bearing is a statically determinate *** the balls spin on both inner and outer races means the ball is controlled by neither the inner nor the outer *** friction between the ball and raceway renders the inner and outer contact angles *** larger the coefficient of friction is,the larger the angle *** tangential traction perpendicular to the rolling direction due to the spin induces a gyro-like rotation of the ball with respect to the raceway even if no inertial effects are *** tangential elastic compliance of contacting surfaces gives rise to locked areas within the contact patch and transforms the sliding lines from circles into *** differential slip due to the close conformity of the ball and raceway makes the sliding and traction distributions asymmetric,which will influence the location of the spinning center of the ball with respect to the *** quasi-static/creepage model can be used to reveal the operating behaviors of ball bearings running under steady conditions and to optimize the design of ball bearings for specific applications.

关键词： ball bearing quasi-static creepage differential slip tangential elastic compliance

同方期刊数据库

Some results on numerical divided difference formulas

在线全文

学校读者我要写书评

暂无评论

Science China mathematics 2005年第11期48卷 1441-1450页

作者： Wang Xinghua,Wang Heyu & Ming-Jun Lai Department of mathematics, {2., hangzhou 31002., China Computing Center, {2., hangzhou 310012. China Department of mathematics, university of Georgia, Athens, GA 30602.7403, USA 1. Department of mathematics Zhejiang University 310028 Hangzhou China 2. Computing Center Zhejiang University 310012 Hangzhou China 3. Department of mathematics University of Georgia 30602-7403 Athens GA USA

The remainder estimates of numerical divided difference formula are given for the functions of lower and higher smoothness, respectively. Then several divided difference formulas with super-convergence are derived wit... 详细信息

关键词： numerical divided difference remainder estimate functions of lower smoothness sufficiently smooth functions super convergence.

Geometric construction of energy-minimizing Bézier curves

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第7期54卷 1395-1406页

作者： XU Gang 1,4,5,WANG GuoZhao 2.& CHEN WenYu 2.3 1 Institute of Graphics and Image,hangzhou Dianzi university,hangzhou 310018,China 2.Department of mathematics,zhejiang university,hangzhou 31002.,China 3 School of Computer Engineering,Nanyang Technological university,639798,Singapore 4 Galaad,INRIA Sophia-Antipolis,2.04 Route des Lucioles,06902.France 5 State Key Lab of CAD & CG,zhejiang university,hangzhou 31002.,China Institute of Graphics and Image Hangzhou Dianzi University Hangzhou China Galaad INRIA Sophia-Antipolis Sophia Antipolis France State Key Lab of CAD & CG Zhejiang University Hangzhou China Department of mathematics Zhejiang University Hangzhou China School of Computer Engineering Nanyang Technological University Singapore Singapore

Modeling energy-minimizing curves have many applications and are a basic problem of Geometric *** this paper,we propose the method for geometric design of energy-minimizing B′ezier ***,the necessary and sufficient condition on the control points for B′ezier curves to have minimal internal energy is *** on this condition,we propose the geometric constructions of three kinds of B′ezier curves with minimal internal energy including stretch energy,strain energy and jerk *** some control points,the other control points can be determined as the linear combination of the given control *** compare the three kinds of energy-minimizing B′ezier curves via curvature combs and curvature plots,and present the collinear properties of quartic energy-minimizing B′ezier *** also compare the proposed method with previous methods on efficiency and ***,several applications of the curve generation technique,such as curve interpolation with geometric constraints and modeling of circle-like curves are discussed.

关键词： curve design minimal energy geometric construction interpolation with constraints circle-like curves

K-Functional, Weighted Moduli of Smoothness, and Best Weighted Polynomial Approximation on a Simplex

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 1999年第3期15卷 395-403,405-406页

作者： Song Li Department of mathematics, {2., hangzhou 31002., P. R. China Department of mathematics Zhejiang University Hangzhou P. R. China

An inverse theorem for the best weighted polynomial approximation of a function in Lwαp（S） is established. We also investigate Besov spaces generated by Freud weight and their connection with algebraic polynomial approximation in Lp（R）wλ, where wα is a Jacobi-type weight on S, 0λ is a Freud weight. For Ditzian-Totik K-functionals on LP（S）, 1≤P≤∞, we obtain a new equivalence expression.

关键词： Weighted moduli of smoothness K-functional Best weighted polynomial approximation Simplex

TENSOR PRODUCTS OF JACOBSON RADICALS IN NEST ALGEBRAS

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2003年第3期24卷 323-330页

作者： DONG ZHE Departinent of mathematics, zhejiang university, {2., China. Institute of mathematics, Fudan university, Shanghai 2.0433, China. zhejiang Univ Dept Math Hangzhou 310027 Peoples R China Fudan Univ Inst Math Shanghai 200433 Peoples R China

This paper studies the tensor product RN RM of Jacobson radicals in nest algebras, and obtains that RN RM = {T∈B(H1 H2. : T(N M)(?)N_ M_, N∈N,M∈M}; and based on the characterization of rank-one operators in RN RM,i... 详细信息

关键词： Jacobson radical Tensor product Nest algebra