"大型(兆瓦级)风力机的空气动力学问题"专刊前言

近年来,风能作为无污染、可再生的自然能源引起了人们的高度重视。风力机是捕获风能的动力装置。大型（兆瓦级）风力机的建造和运行涉及到一系列复杂的空气动力学理论和应用问题:如叶片翼型升力特性、叶片气动弹性和气动噪声、风力机风洞模拟实验以及叶片气动优化设计等,成为近期国内外力学、工程界研究的前沿和热点之一。本刊特邀请中国科学院力学研究所胡文瑞院士、南京航空航天大学王同光教授和上海交通大学李晔教授担任客座编委,策划组织了题为"大型（兆瓦级）风力机的空气动力学问题"专刊,集中报道国内外针对上述问题的最新研究成果和进展趋势。     

分销仓储配送中心定货决策模拟系统研究

本对于分销仓储本着中心在客户需求量和再订货提前期都是随机性的情况，利用Arena模拟软件，通过对再订货点模型进行了模拟，求出可使系统成本较少的订购批量及再订货点存货水平的组合，从而确定最佳订货策略，解决现实中这种“双随机性”的复杂订货决策问题。     

第五届现代数学和力学(MMM-V)学术会议纪要

中国力学学会理性力学和力学中数学方法专业委员会的第五届现代数学和力学(MMM-V)学术会议于1993年4月15日至4月17日在中国矿业大学(徐州)举行.会议由陈至达教授担任主席.出席这次会议的专家、学者及来宾共计120人左右.我国老一辈应用数学和力学科学家钱伟长教授及其夫人孔祥英女士也出席了这一次会议,使与会代表受到了很大的鼓舞.会议开幕式由中国科学院学部委员北京大学教授郭仲衡主持,会议执行主席中国矿业大学教授陈至达致开幕词,中国矿业大学党委书记兼校长郭育光教授讲了话,对钱老及与会学者来校出席会议表示热烈欢迎,并预祝大会取得圆满成功.本次会议地区组织委员会秘书长中国矿业大学教授李安昌宣读了这次会议的论文集代前言“祝贺应用数学和力学科学家钱伟     

“随机振动及工程应用”专刊征稿公告

正《应用数学和力学》期刊由中国近代力学、应用数学的奠基人之一钱伟长先生于1980年创建并亲自担任首届主编。自2013年钟万勰院士出任新一届主编以来,更大力强调本刊反映国内自主创新成果和所刊论文对我国建设事业,特别是对重大工程项目的推动和促进作用。为此本刊拟于2016年年末或2017年年初出版一期"随机振动及工程应用"专刊。     

随机变量的变分原理及有限元法

本文将材料的随机性,结构几何形状的随机性,力的边界条件和位移边界条件的随机性,直接引入泛函变分表达式中,应用小参数摄动法,提出了统一的随机变量的变分原理及有限元法.从算例表明,应用此方法处理随机变量的力学问题,具有程序实施简便,计算效率高等优点.     

“大型(兆瓦级)风力机的空气动力学问题”专刊预告

近年来,风能作为无污染、可再生的自然能源引起了人们的高度重视。风力机是捕获风能的动力装置。大型(兆瓦级)风力机的建造和运行涉及到一系列复杂的空气动力学理论和应用问题:如叶片翼型升力特性、叶片气动弹性和气动噪声、风力机风洞模拟实验以及叶片气动优化设计等,成为近期国内外力学、工程界研究的前沿和热点之一。     

沉痛悼念我刊编委刘高联院士

我刊编委、中国科学院院士、著名工程热物理学家和力学家、上海大学及上海市应用数学和力学研究所刘高联教授因病医治无效，于2008年3月8日10时50分在上海逝世，享年76岁。     

“苏步青奖”、“苏步青应用数学奖”新闻发布会举行

国际工业与应用数学联合会(ICIAM)“苏步青奖”和中国工业与应用数学学会(CSIAM)“苏步青应用数学奖”新闻发布会，年前于教育部新闻发布厅举行。中国工业与应用数学学会副理事长阵叔平教授主持了会议。中国科学院院士、国际工业与应用数学联合会执行委员、中国工业与应用数学学会理事长李大潜教授首先介绍了苏步青先生生平以及“苏步青奖”及“苏步青应用数学奖”的有关情况；     

陀螺系统随机振动分析的辛本征展开方法

探讨了受随机载荷作用下陀螺阻尼系统随机动力响应问题.虚拟激励法作为随机振动分析的一种高效、精确方法已经广泛应用于结构抗震、抗风等工程领域.在以单类物理变量描述的Lagrange(拉格朗日)体系框架下,振型分解方法已被有效应用于上述随机振动问题的模型自由度缩减.然而,对于陀螺系统的随机振动问题,由于陀螺效应的存在,基于Rayleigh商本征值的振型分解方法受到很大限制.对此,首先给出了陀螺系统辛本征值问题的一般形式.然后对于受平稳随机载荷激励的陀螺系统(无阻尼或有阻尼)引入虚拟激励法,基于辛本征空间展开推导了系统随机振动响应功率谱的求解列式;对于仅考虑陀螺效应的保守系统(无阻尼),该求解列式可以表述为一个显式表达式.在数值算例中,应用该文提出的方法分析了平稳随机载荷作用下一类阻尼陀螺系统的随机振动响应问题,通过与其它方法进行对比,验证了该方法的精确性和有效性.     

纪念钱伟长先生诞辰100周年北大核心CSCD

钱伟长（1912年10月9日-2010年7月30日） 今年10月9日,是本刊创办人钱伟长教授诞辰100周年。钱伟长教授是我国最杰出的、也是国际知名的力学和应用数学家之一。他在上世纪40年代关于弹性板壳内禀理论的工作,不仅统一了当时众说纷纭的各种板壳理论,同时也开创了理性力学的新领域。在40到50年代关于奇异摄动理论和弹性圆薄板大挠度问题的研究、60年代关于广义变分原理的研究,都是领一代风气之先的开创性工作。他不仅在应用数学和力学的各个方面作出了重要贡献,对中国力学事业发展所起的作用也是不可替代的,他是中国的第一个力学专业、第一个力学研究机构的创办人,是促进中国非线性力学发展的带头人,他被公认为中国当代力学的四位奠基人之一。     

Optimal estimation of nonlinear state nonlinear observation systems

The concept of this work is that research on nonlinear modeling and estimation in a stochastic framework brings with it the study of the orthogonality structure of the probability densities involved. The connection is made by means of a probabilistic quantity, called the theta function, which under fairly broad integrability conditions defines the class of factorable random processes. These processes play a central role in the derivation of a recursive estimation scheme which is mathematically optimal and computationally attractive. The theory of factorable processes is simpler and its relevance to estimation practice is more direct than that of other sophisticated nonlinear approaches, such as martingales and Lie algebras.The author is indebted to Prof. D. R. Smith, University of California, San Diego, for helpful suggestions.     

Dynamics of Team Member Replacements from Complex Systems Theory

Simulations based on the NK model are carried out to address team member replacements that follow tweaking (i.e., gradual changes) of the strategy of the team leader. For simple teams in which the team members do not interact, team member replacements occur independently. However, for teams in which team members interact with other team members, team member replacements occur as cascades. In these cascades, the replacement of one team member triggers the replacement of another, which triggers the replacement of yet another, and so on. These cascades of team member replacements are largest for teams with intermediate complexity, in which each member interacts with between and of the other team members. The cascades are roughly independent of team size, and so smaller teams are more volatile in that the cascades affect a larger fraction of the team.Daniel J. Lacks is the C. Benson Branch Professor of Chemical Engineering at CaseWestern Reserve University. Prof. Lacks received his B.S. in chemical engineering from Cornell University in 1987, and his Ph.D. in chemistry from Harvard University in 1992. Following a postdoctoral fellowship at MIT from 1993–1994, Prof. Lacks was on the faculty of the chemical engineering department at Tulane University from 1994–2003. Prof. Lacks joined the faculty at Case in 2003. His research interests involve the simulation of nonequilibrium processes, ranging from physical processes such as fluid flow and fracture in glasses, to nonphysical processes such as biological evolution and chemical process optimization.     

The multidimensional plateau problem in Riemannian varieties

This paper is the author's abstract of his dissertation for the degree of Doctor of Physico-Mathematical Sciences. The dissertation was defended on September 29, 1972 at a session of the Council of the Mechanico-Mathematical Faculty of M. V. Lomonosov Moscow University. The official opponents were Prof. V. M. Alekseev, Doctor of Phys.-Mat. Sci.; Prof. D. V. Anosov, Doctor of Phys.-Mat. Sci.; and Prof. M. M. Postnikov, Doctor of Phys.-Mat. Sci.Translated from Matematicheskie Zametki, Vol. 13, No. 1, pp. 159–167, January, 1973.     

Numerical experiments with ABS algorithms for linear systems on a parallel machine

Numerical results are obtained on sequential and parallel versions of ABS algorithms for linear systems for both full matrices andq-band matrices. The results using the sequential algorithm on full matrices indicate the superiority of a particular implementation of the symmetric algorithm. The condensed form of the algorithm is well suited for implementation in a parallel environment, and results obtained on the IBM 4381 system favor a synchronous implementation over the asynchronous one. Results are obtained from sequential implementations of theLU, Cholesky, and symmetric algorithms of the ABS class forq-band matrices able to reduce memory storage. A simple parallelization of do-loops for calculating components gives interesting performances.This work has been developed in the framework of a collaboration between IBM-ECSEC, Rome, Italy, and the Department of Mathematics of the University of Bergamo, Bergamo, Italy.The author is grateful to Prof. J. Abaffy (University of Economics, Budapest), Prof. L. Dixon (Hatfield Polytechnic), and Prof. E. Spedicato (Department of Mathematics, University of Bergamo) for useful suggestions.     

Stochastic Navier-Stokes Equations

The purpose of this article is to survey some results related to the theory of stochastic Navier-Stokes equations (SNSE). The interest of SNSE arises from modelling turbulence. We begin to show how SNSE can be introduced intuitively from the random motion of particles. We then review briefly the deterministic theory and present the main core of existence theory for NSE. We also discuss uniqueness issues. We end up by showing how the splitting-up method provides a useful constructive approach to existence, and by presenting some extensions, like weakening assumptions or considering the special case of small initial data.These lectures have been delivered in the Frontiers Lectures program of Texas A&M University. The author thanks Prof. Goong Chen for his invitation.     

海洋立管涡激损伤分析的虚拟激励法概述

立管是连接海底钻井和海上平台的重要系统.涡激振动是造成立管疲劳损伤的主要因素.受海流的随机作用,立管涡激振动表现出不确定性,对这种随机振动进行快速有效地分析,对于立管的工程设计具有非常重要的意义.考虑随机激励作用,要比确定性激励困难得多,虚拟激励法对于克服这种困难具有很好的效果.近年来,应用虚拟激励法分析立管的涡激损伤问题,取得一些成果,该文对此作一概略的叙述.     

Resonance theorems and functional series

Self-referred dissertation in competition for the academic doctor's degree in physico-mathematical sciences (printed with elisions). The dissertation was defended on May 7, 1971 at the teaching council of the mechanics-mathematics faculty of the Moscow State University. The official opponents were: Dr. Physico-Mathematical Sciences, Prof. N. P. Kuptsov, Dr. Physico-Mathematical Sciences, Prof. A. M. Olevskii, and Corresponding Member of the Academy of Sciences of the Armenian SSR, Dr. Physico-Mathematical Sciences, Prof. A. A. Talalyan.Translated from Matematicheskie Zametki, Vol. 10, No. 5, pp. 583–595, November, 1971.The author extends hearty thanks to Prof. P. L. Ul'yanov for purposeful scientific conferences on the results of the dissertation.     

车辆随机振动功率谱分析的虚拟激励法概述

车辆受到路面或轨道不平度激励会产生随机振动,对这类随机振动进行快速有效的分析对于提高车辆性能具有非常重要的意义．而这类随机振动的分析,历来都只能将车辆模拟为自由度很低的弹簧质量体系,其计算精度难于保证．特别在需要计算疲劳应力集中的情况,需要使用网格很密的有限元模型,计算困难就更为突出．此外,在考虑多个车轮受到路面随机激励时,就更难应用效率相对较高的频域分析来计算车辆的随机振动;而只能借助于一条或几条路面不平度样本,让车轮在上面移动,借助数值积分工具而粗略地得到随机响应的统计特性．效率很低而且精度不高．虚拟激励法对于克服上述困难具有很好的效果;目前已在我国的汽车、火车、磁浮列车等领域获得日益广泛的应用．该文对此作一概略的叙述．     

虚拟激励法在国内外工程界的应用回顾与展望

《随机振动的虚拟激励法》自1985年正式发表以来,逐渐得到许多工程领域的认可和采用,解决了很多重要而困难的工程问题.该方法不但被国内某些工程规范所推荐,而且被3种国际工程手册成章刊载,在国际上亦占有了一席之地.该文是笔者参考了数百篇国内外论文,依据其中一部分在11个工程领域对虚拟激励法的应用和一些学者的评论所撰写的综述.借以让更多工程技术人员和研究者对虚拟激励法有较为全面的了解,以结合各自工程领域更有效地开展对随机振动理论和方法研究成果的应用和发展.     

Optimal monotone hysteretic Markov policies in anM/M/1 queueing model with switching costs and finite time horizon

In anM/M/1 queueing model, a decision maker can choosem pairs of arrival- and service rates. He can change his action at any time epoch, a switch of action costs an amount depending on the size of the switch. Besides that there are continuously incurring costs. Over a finite time horizon, there exists an optimal monotone hysteretic Markov policy. This is shown essentially by the technique of time discretization.The work producing this article was done during a half year stay at the University of Leiden, The Netherlands, with Prof. Arie Hordijk. A technical report (a more detailled version of this article) was written there [6]. The opportunity for this stay was given by the University of Bonn, Germany, where the author, at that time, worked as scientific assistant of Prof. M. Schäl.