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The Superconvergence of Mixed Finiteelement Methods for Nonlinear Hyperbolicequations

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 155-158页

作者： Yanping CHeN and Yunqing HUANG(Department of Mathematics. Nanjing University, Nanjing 210008, China)(Institute of comp. & Appl. Math., Xiangtan University, Xiangtan 411105. China)e-mail: huangyq@*** Department of Mathematics Nanjing University Nanjing 210008 China Institute of comp. and Appl. Math. Xiangtan University Xiangtan 411105 China

Improved L2-error estimates are computed for mixed finite element methods for second order nonlinear hyperbolic equations. Superconvergence results, L∞intime and discrete L2 in space, are derived for both the solutio... 详细信息

关键词： nonlinear hrperbolic equation mixed finite element methods superconvergence

移动代理环境下实现微支付系统—扩展MilliCent协议

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计算机工程与应用 2004年第26期40卷 145-148页

作者：于宝东金连甫陈平浙江大学计算机系软件所杭州310027

在整个电子商务活动中,网上支付是其中很重要的一环。对于大额交易来说,关心的主要是安全性。但是,对于交易额不高的交易来说,速度和成本就成了首要考虑的因素。MilliCent协议是一个优秀的微支付协议。但是,它不能够提供一种可使用的“... 详细信息

在整个电子商务活动中,网上支付是其中很重要的一环。对于大额交易来说,关心的主要是安全性。但是,对于交易额不高的交易来说,速度和成本就成了首要考虑的因素。MilliCent协议是一个优秀的微支付协议。但是,它不能够提供一种可使用的“硬通货”,需要首先进行兑换工作,为应用增加了麻烦。这篇文章对Millicent进行了改进,引入了“硬通货”的概念,增强了它的方便性和实用性。

关键词：移动代理微支付系统单向哈希函数

Cyclokinetic models and simulations for high-frequency turbulence in fusion plasmas

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Frontiers of physics 2016年第5期11卷 23-56页

作者： Zhao Deng R. e. Waltz Xiaogang Wang Department of Physics Harbin Institute of Technology Harbin 150001 China

Cyrokinetics is widely applied in plasma physics. However, this framework is limited to weak turbulence levels and low drift-wave frequencies because high-frequency gyro-motion is reduced by the gyro-phase averaging. In order to test where gyrokinetics breaks down, Waltz and Zhao developed a new theory, called cyclokinetics [R. e. Waltz and Zhao Deng, Phys. Plasmas 20, 012507 （2013）]. Cyclokinetics dynamically follows the high-frequency ion gyro-motion which is nonlineaxly coupled to the low-frequency drift-waves interrupting and suppressing gyro-averaging. Cyclokinetics is valid in the high-frequency （ion cyclotron frequency） regime or for high turbulence levels. The ratio of the cyclokinetic perturbed distribution function over equilibrium distribution function δf/F can approach 1. This work presents, for the first time, a numerical simulation of nonlinear cyclokinetic theory for ions, and describes the first attempt to completely solve the ion gyro-phase motion in a nonlinear turbulence system. Simulations are performed [Zhao Deng and R. e. Waltz, Phys. Plasmas 22（5）, 056101 （2015）] in a local flux-tube geometry with the parallel motion and variation suppressed by using a newly developed code named rCYCLO, which is executed in parallel by using an implicit time-advanced eulerian （or continuum） scheme [Zhao Deng and R. e. Waltz, comp. Phys. Comm. 195, 23 （2015）]. A novel numerical treatment of the magnetic moment velocity space derivative operator guarantee saccurate conservation of incremental entropy. By comparing the more fundamental cyclokinetic simulations with the corresponding gyrokinetic simulations, the gyrokinetics breakdown condition is quantitatively tested. Gyrokinetic transport and turbulence level recover those of cyclokinetics at high relative ion cyclotron frequencies and low turbulence levels, as required. Cyclokinetic transport and turbulence level are found to be lower than those of gyrokinetics at high turbulence levels and low-Ω＊ values wit

关键词： turbulence cyclokinetics gyrokinetics drift waves ion cyclotron modes

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鼓励性微分对策中鼓励性策略的存在与构造

厦门大学学报(自然科学版) 1988年第4期 391-397页

作者：曾晓军厦门大学计算机与系统科学系

应用凸分析方法研究鼓励性微分对策问题,给出完全信息和闭环信息下鼓励性策略的存在条件并构造出策略的表达式。

关键词：鼓励性微分对策鼓励性策略闭环策略

Research on Multi-Agent Based Framework of Reconfigurable Shop Floor Control System

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厦门大学学报（自然科学版） 2002年第S1期41卷 178-179页

作者： GAO e, WANG Zhi-sen (CIMS Institute, Hefei University of Technology, Hefei 230009, China)

Manufacturing systems are in a dynamically changing e nvironment with uncertainty. Management of complexity, changes and disturbances is one of the key issues of production. The traditional hierarchical control of CIM systems limits the agility and the flexibility of the shop floor control sys tems and makes the reconfiguration and maintenance of shop floor control systems need high cost and much time. So new architectures are required to meet these c hallenges for the shop floor control systems. Recent fundamental research in distributed artificial intelligence and related applied research in intelligent manufacturing systems have shown that the Multi -Agent based system is one of the most promising methods. In a multi-agent man ufacturing system, the agents react to the information acquired from environment and communicate with other agents to co-operate to solve the global problem. I n this paper, a framework of reconfigurable shop floor control system based on m ulti-agent is presented. The concept of dynamic and logical manufacturing cell is proposed to organize manufacturing resources to achieve the ability of re configuration in dynamic shop floor environment. The framework is composed of three levels. First, the level of shop floor comp rises order agent, resource management agent, product management agent and t ask agent. Second, the level of dynamical cells consists of production agents an d control agents. Finally, the resource agents, such as AGV agents and machine a gents, belong to the equipment level. The control architecture in the framework is different from hierarchical control. It is hybrids of hierarchical and hetera rchical control architecture. The Contract Net protocol and its bidding mechanism are suitable and efficient t o implement the dynamic and logical manufacturing cells. Based on the Contract N et Model, dynamic negotiation during the process of forming the dynamic and logi cal manufacturing cells is analyzed in the paper. In this pape

关键词： agent Multi-Agent System (MAS) dynamic and log ical manufacturing cell

骨形态发生蛋白-2对软骨寡聚基质蛋白在软骨细胞内表达的影响

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北京大学学报（医学版） 2003年第3期35卷 317-320页

作者：田华 Carrie FANG Paul e.DICeSARe 北京大学第三医院骨科北京100083 美国纽约大学关节病医院

目的 :定量研究骨形态发生蛋白 (BMP 2 )对软骨寡聚基质蛋白 (comp)基因在人软骨细胞及ATDC5 5细胞内表达的影响。方法 :原代培养成人及胚胎的关节软骨细胞 ,经BMP 2刺激后 ,利用real timeRT PCR定量分析comp基因的表达情况 ;采用静息... 详细信息

目的 :定量研究骨形态发生蛋白 (BMP 2 )对软骨寡聚基质蛋白 (comp)基因在人软骨细胞及ATDC5 5细胞内表达的影响。方法 :原代培养成人及胚胎的关节软骨细胞 ,经BMP 2刺激后 ,利用real timeRT PCR定量分析comp基因的表达情况 ;采用静息期不表达comp基因的鼠源性成软骨细胞株ATDC5 5作为研究对象 ,给以BMP 2刺激 ,通过RT PCR检测comp表达的变化 ;将comp基因的全长启动子克隆到报告基因Luciferase的上游并转染入ATDC5 5细胞 ,分别给以 5 0 0 μg·L-1的BMP 2和 /或 10 μg·L-1的Noggin刺激 ,测定其对Luciferase活性的影响。结果 :BMP 2使成人软骨细胞内的comp基因表达提高近 3倍 ,而对胚胎软骨细胞的作用较弱 ,提高了1.5倍 ;comp基因在胚胎软骨细胞内的基础表达量约是在成人软骨细胞内的 2倍 ;经BMP 2刺激后ATDC5 5细胞株明显表达comp基因 ,并且BMP 2的这种效应能够被其拮抗剂Noggin所抑制 ;BMP 2明显促进了Luciferase的活性 ,约提高了 5倍 ,且Noggin特异性的抑制了BMP 2的这种作用。结论 :BMP 2能够明显促进comp基因在人关节软骨细胞及鼠源性成软骨细胞株ATDC5 5内的表达。

关键词：骨形态发生蛋白-2 软骨寡聚基质蛋白软骨细胞基因表达

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相协样本半参数回归模型估计的强相合性

数学研究 2004年第4期37卷 431-437页

作者：李军杨善朝江苏工业学院信息科学系广西师范大学数学与计算机科学学院江苏常州213016 广西桂林541004

考虑半参数回归模型Y（ j）（xin,tin） =tinβ +g（xin） +e（ j）（xin） ,1 j m,1 i n.利用最小二乘法和权函数估计方法 ,定义β,g的估计量βm ,n和 gm ,n（x） ,在负相依样本及较弱的条件下证明了这些估计的强相合性 ,得到了与独... 详细信息

考虑半参数回归模型Y（ j）（xin,tin） =tinβ +g（xin） +e（ j）（xin） ,1 j m,1 i n.利用最小二乘法和权函数估计方法 ,定义β,g的估计量βm ,n和 gm ,n（x） ,在负相依样本及较弱的条件下证明了这些估计的强相合性 ,得到了与独立情形一致的结论 .

关键词： NA相协样本半参数回归模型强相合性

WIDe　SeNSe　STABILITY　OF　compLeX　SYSTeMS　OF　DIFFeReNTIAL　eQUATIONS　OF　ARBITRARY　DIMeNSION

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Chinese Annals of Mathematics,Series B 1994年第2期15卷 193-204页

作者： ZIAD ZAHReDDINe(Department of Matehematics and computer Secience, Faculty of Science, U. A. e. University, Al-Ain,P. O. Box 17551, Uited Arab emirates) UNITeD ARAB eMIRATeS UNIV AL AIN FAC SCIDEPT MATH & COMP SCIAL AINU ARAB EMIRATES

It is shown how the extended Routh array (eRA), which naturally extends the Routh array to the complex case, can handle the appearance of vanishing leading array elements, and how after minor modifications it can be used to test the stability in the wide sense of systems of differential equations with complex coefficients and of arbitrary dimension. The recent result advanced for the asymptotic or strict sense stability of such systems falls out as a special case.

关键词： Stability Wide sence stability Routh array extended Routh array.

SOMe ReSULTS ON THe COeFFICIeNTS OF INTeGRATeD eXPANSIONS OF ULTRASPHeRICAL POLYNOMIALS AND THeIR INTeGRALS

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Analysis in Theory and Applications 2001年第3期17卷 69-84页

作者： e.H.Doha S.I.eL-Soubhy Department of Mathematics Faculty of Science Cairo UniversityGiza-Egypt Department of Mathematics Girl's College of EducationJeddahSaudi Arabia

The formula of expressing the coefficients of an expansion of ultraspherical polynomials that has been integrated an arbitrary number of times in terms of the coefficients of the original expansion is stated in a more compact form and proved in a simpler way than the formula of Phillips and Karageorghis (1990). A new formula is proved for the q times integration of ultraspherical polynomials, of which the Chebyshev polynomials of the first and second kinds and Legendre polynomials are important special cases. An application of these formulae for solving ordinary differential equations with varying coefficients is discussed.

关键词： differential equations Partial Differential equations Spectral Methods Chebyshev polynomials Legendre polynomials Numerical Analysis Boundary Value Problems Spectral Approximation Parabolic equations Applied Mathematics Accurate Solution Fluid Dynamics Heat Transfer new formula Methods for