检索结果-南通市图书馆

Deterministic secure quantum communication without unitary operation based on high-dimensional entanglement swapping

在线全文

学校读者我要写书评

暂无评论

Science china(Information sciences) 2012年第2期55卷 360-367页

作者： LIU ZhiHao1,CHEN HanWu1,LIU WenJie2,XU Juan1 & LI ZhiQiang3 1school of Computer Science and Engineering,Southeast university,Nanjing 211189,china 2school of Computer and Software,Nanjing university of Information Science & Technology,Nanjing 210044,china 3College of Information Engineering,yangzhou university,yangzhou 225009,china 1. school of Computer Science and Engineering Southeast University Nanjing 211189 China2. School of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China3. College of Information Engineering Yangzhou University Yangzhou 225009 China

By analysis of the basic properties of entanglement swapping of high-dimensional Bell states,a universal and general deterministic secure quantum communication(DSQC)protocol is proposed,in which unitary operation is not *** making use of the results of high-dimensional Bell measurement,the sender and the receiver can encode and decode the message respectively by performing the modular addition and *** mutually complementary bases are constructed;and according to the property of mutual complement,a method for checking security of the high-dimensional quantum channel is put *** common attack strategies are analyzed,and the corresponding error rates are *** the upper bound of the threshold of error rate is deduced.

关键词： deterministic secure quantum communication high-dimensional Bell state entanglement swap-ping high-dimensional Bell measurement

ELECTROCHEMICAL COPOLYMERIZATION OF ANILINE AND AZURE B

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2001年第5期19卷 483-492页

作者： Dan Shan Shao-lin Mu Bing-wei Mao Yong-fang Li Department of Chemistry school of Science, yangzhou university yangzhou 225002, china State Key Laboratory of Physical Chemistry of Solid Surface, Xiamen university Xiamen 361005 china Center for Molecular Science. Institute of Chemistry Chinese Academy of sciences, Beijing 100080 china yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China Xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

The electrochemical copolymerization of aniline and N,N,N'-trimethylthionin (azure B) in aqueous solutions has been carried out using the potential sweep method. The optimum conditions for the coelectrodeposition are that the pH value and the temperature of the electrolytic solution are controlled at 5.57 and 30 degreesC, respectively, and the scan potential range is set between -0.25 and 1.10 V (versus SCE). The copolymerization rate of aniline and azure B is about 3 times larger than that of aniline in the absence of azure B. The copolymerization of aniline and azure B was verified from the results of visible spectra during electrolysis, FTIR spectra and the atomic force microscopy (AFM) images of the polymers. The in situ visible spectrum for the electrolysis of the solution containing aniline and azure B is different from that of the respective aniline and azure B. The FTIR spectrum of the copolymer is not a superposition of that of polyaniline and poly(azure B). The AFM image of the copolymer is different from those of polyaniline and poly(azure B) and is not a mixture of individual polymers. The conductivity of the copolymer synthesized at pH 5.57 is four orders of magnitude higher than that of polyaniline synthesized under the same conditions, but in the absence of azure B. The electrochemical properties of the copolymer are mainly attributed to polyaniline, but the copolymer has a better electrochemical reversibility and a much faster charge transfer than those of polyaniline.

关键词： aniline azure B electrochemical copolymerization characterization of copolymer electrochemical property

黄河流域环境治理绩效的空间关联网络及影响因素分析

在线全文

学校读者我要写书评

暂无评论

环境科学研究 2024年第7期37卷 1546-1560页

作者：段洋洲王奕淇甄雯青长安大学经济与管理学院陕西西安710064

黄河流域作为我国重要的生态安全屏障,探索其环境治理绩效的空间关联网络特征及影响因素,有利于推进黄河流域生态保护和高质量发展。本文基于2006−2021年黄河流域60个地级及以上城市的面板数据,在构建超效率SBM模型(Slacks-Based Measur... 详细信息

黄河流域作为我国重要的生态安全屏障,探索其环境治理绩效的空间关联网络特征及影响因素,有利于推进黄河流域生态保护和高质量发展。本文基于2006−2021年黄河流域60个地级及以上城市的面板数据,在构建超效率SBM模型(Slacks-Based Measurement,SBM)测度黄河流域环境治理绩效的基础上,利用修正的引力模型和社会网络分析法探讨了环境治理绩效的空间关联网络特征及其影响因素。结果表明:①2006−2021年黄河流域环境治理绩效呈波动式上升趋势,且流域上游、中游和下游的环境治理绩效平均值都小于1,环境治理绩效整体偏低。②黄河流域各城市间环境治理绩效的网络密度较低,网络结构相对稳定,关联效率较高,不存在等级森严的网络结构,且济南市、青岛市等城市在网络中处于核心位置,巴彦淖尔市、白银市等城市处于边缘位置。③郑州市、淄博市等中下游城市对板块内外均产生溢出效应,临汾市、西宁市等中上游城市是关联网络的“发动机”,青岛市、济南市等区域核心城市成为关联网络中的受益方,西安市、兰州市等位于黄河“几”字弯都市圈的城市担任了桥梁作用。④地理空间邻近、经济发展差异及产业结构差异对黄河流域环境治理绩效空间关联网络产生正向影响,环境规制差异、科技创新差异、对外开放差异及政府调控差异的影响效果呈现阶段性变化的特征。研究显示,黄河流域环境治理绩效存在显著的空间关联和溢出效应,但空间关联程度较低,需不断提升空间关联网络的紧密程度,推动黄河流域区域间环境的协同治理与平衡发展。

关键词：环境治理绩效空间关联网络影响因素社会网络分析黄河流域

A priori error analysis of a discontinuous Galerkin approximation for a kind of compressible miscible displacement problems

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第10期53卷 2679-2696页

作者： YANG JiMing1,& CHEN YanPing2 1College of Science,Hunan Institute of Engineering,Xiangtan 411104,china 2school of mathematical sciences,South china Normal university,Guangzhou 510631,china 1. College of Science Hunan Institute of Engineering Xiangtan 411104 China2. School of Mathematical Sciences South China Normal University Guangzhou 510631 China

A kind of compressible miscible displacement problems which include molecular diffusion and dispersion in porous media are investigated.A symmetric interior penalty discontinuous Galerkin (SIPG) method is applied to the coupled system of flow and *** the induction hypotheses instead of the cut-off operator and the interpolation projection properties,a priori hp error estimates are *** error bounds in L2(H1) norm for concentration and in L∞(L2) norm for velocity are optimal in h and suboptimal in p with a loss of power 1/2.

关键词： a priori error discontinuous Galerkin compressible miscible displacement coupled system

Sieve M-estimation for semiparametric varying-coefficient partially linear regression model

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第8期53卷 1995-2010页

作者： HU Tao 1,2 & CUI HengJian 1,2 1 school of mathematical sciences,Beijing Normal university,Laboratory of Mathematics and Complex Systems,Ministry of Education,Beijing 100875,china 2 school of mathematical sciences,Capital Normal university,Beijing 100048,china 1. school of mathematical sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China2. School of Mathematical Sciences Capital Normal University Beijing 100048 China

This article considers a semiparametric varying-coefficient partially linear regression *** semiparametric varying-coefficient partially linear regression model which is a generalization of the partially linear regression model and varying-coefficient regression model that allows one to explore the possibly nonlinear effect of a certain covariate on the response variable.A sieve M-estimation method is proposed and the asymptotic properties of the proposed estimators are *** main object is to estimate the nonparametric component and the unknown parameters *** is easier to compute and the required computation burden is much less than the existing two-stage estimation ***,the sieve M-estimation is robust in the presence of outliers if we choose appropriate ρ(·).Under some mild conditions,the estimators are shown to be strongly consistent;the convergence rate of the estimator for the unknown nonparametric component is obtained and the estimator for the unknown parameter is shown to be asymptotically normally *** experiments are carried out to investigate the performance of the proposed method.

关键词： partly linear model varying-coefficient robustness optimal convergence rate asymptotic normality

RADIAL BASIS FUNCTION INTERPOLATION IN SOBOLEV SPACES AND ITS APPLICATIONS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2007年第2期25卷 201-210页

作者： Manping Zhang (school of mathematical sciences,Fudan university,Shanghai 200433,china Institute of Computational Mathematics,Chinese Academy of sciences,Beijing 100080,china school of mathematical sciences Fudan University Shanghai 200433 China Institute of Computational Mathematics Chinese Academy of Sciences Beijing 100080 China

In this paper we study the method of interpolation by radial basis functions and give some error estimates in Sobolev space H^k（Ω）（k 〉 1）. With a special kind of radial basis function, we construct a basis in H^k（Ω） and derive a meshless method for solving elliptic partial differential equations. We also propose a method for computing the global data density.

关键词： Sobolev space Radial basis function Global data density Meshless method

SHORT FATIGUE CRACK PARAMETER BASED ON THE TOTAL CRACK AREA

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 235-240页

作者： Z.X. Wu and X. C. Wu Engineering College, yangzhou university, yangzhou 225009, china Eng. Coll. Yangzhou Univ. Yangzhou 225009 China

The progressive fatigue damage of a material is closely related to the whole population of cracks on its surface. In order to understand which parameter is a more useful indicator of fatigue damage, rotatory bending fatigue tests were carried out using smooth specimens of medium-carbon steel. The behavior of short crack propagation during fatigue was examined and a new parameter total crack area was suggested. The aim of this paper is to extend the research on fatigue damage in the already studied steel and to study how these damage parameters are correlated with the process of fatigue damage in order to evaluate the effectiveness of damage detection methods.

关键词： Bending strength Crack initiation Crack propagation Fatigue testing Parameter estimation

A new scheme of digital communication using chaotic signals in MIMO channels

在线全文

学校读者我要写书评

暂无评论

Science china(Information sciences) 2012年第10期55卷 2183-2193页

作者： MA HuanFei 1 & KAN HaiBin 2 1 school of mathematical sciences,Soochow university,Suzhou 215006,china 2 school of Computer Science,Fudan university,Shanghai 200433,china 1. school of mathematical sciences Soochow University Suzhou 215006 China 2. school of Computer Science Fudan University Shanghai 200433 China

This paper proposes a new digital communication scheme,which uses chaotic signals based on the adaptive synchronization and parameter identification technique of chaotic systems reported *** to the multi signal character,this scheme combines the chaotic signal transmission with the MIMO channel technique in a wireless environment,which is different from the traditional chaotic communication *** a practical perspective,an outline of modulation,channel model,demodulation and non-coherent detection is ***,system performance is evaluated by simulations,and improvements on this scheme are also discussed.

关键词： chaotic modulation chaotic digital communication mapping parameters MIMO channel

A quantitative program for Hadwiger's covering conjecture

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第9期53卷 2551-2560页

作者： ZONG Chuanming school of mathematical sciences,Peking university,Beijing 100871,china 1. school of mathematical sciences Peking University Beijing 100871 China

In 1957,Hadwiger made a conjecture that every n-dimensional convex body can be covered by 2n translates of its *** to now,this conjecture is still open for all n *** 1933,Borsuk made a conjecture that every n-dimensional bounded set can be divided into n + 1 subsets of smaller *** to now,this conjecture is open for 4 n *** this article we encode the two conjectures into continuous functions defined on the spaces of convex bodies,propose a four-step program to attack them,and obtain some partial results.

关键词： convex body Hadwiger’s conjecture Banach-Mazur metric β-net Borsuk’s conjecture