ON THE NONEXISTENCE OF PERIODIC SOLUTIONS FOR LIENARD-TYPE EQUATIONS

1.IntroductionConsiderthefollowinggeneralizedLi6nardtypeequationwhereshallowing[1],thisequationwillbecalledasaLi6nard-typeequationofordern.Whenn=1,theequation(1.1)canbewrittenasthefollowingformClearly)whenfi(x)=j(x),f200=0,theequation(1.3)isreducedtothewellknownLi6nardequationx j(x)x g(x)=0.(1.4)Recently,theequation(1.3)hasalreadybeenstudiedwithparticularemphasisontheex-istenceanduniquenessofperiodicsolutionsbyseveralauthors.Forexample,needmanandKuangll],GuidorizzilZ],ZhouJinI3],andJiangJ…     

NON-CLASSICAL GENERALIZED SOLUTIONS FOR SOME HYPERBOLIC SYSTEMS

1.IntroductionThemostspecialfeatureofconservationlawsofhyperbolicsystemsisthattheirsolutionsalwayshavediscolltinuities.ThiskindofdiscontinuityrepresentstheshoCkwavephenomena.Sopeopleintroducetheideaofgeneralizedsolutionwhichsatisfiesequationsinthesenseofdistribution.Underthisdefinition,alotofachievementshavebeenobtainedsince1950'sinthisfield.However,inrecelltyears,manyauthors(see[l--6])discoveredthatthereisnoexistenceanduniqllenessofsolutionstoRiemannproblemsforsomeconservationlaws.Bynumeric…     

ON THE EXISTENCE OF MEROMORPHIC SOLUTIONS OF ALGEBRAIC DIFFERENTIAL EQUATIONS

ＯＮＴＨＥＥＸＩＳＴＥＮＣＥＯＦＭＥＲＯＭＯＲＰＨＩＣＳＯＬＵＴＩＯＮＳＯＦＡＬＧＥＢＲＡＩＣＤＩＦＦＥＲＥＮＴＩＡＬＥＱＵＡＴＩＯＮＳ￥ＹＵＡＮＷｅｎｊｕｎ（ＤｅｐａｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＸｉｎｊｉａｎｇＮｏｏｒｍａｌＵｎｉｖｅｒｓ...     

SOME DISCUSSION ON THE CONDITIONS OF COMPLETE CONVERGENCE FOR SUMS OF B-VALUED RANDOM ELEMENTS

1. Introduction and Main ResultsSince the definition on complete convergence of real random variables was introduced by Hsuand Robbins[1], there have been extensive literature on the complete convergence of i.i.d. realvalued random variables, see Baum and Katz ([2]), Bat and Su ([3]). In 1989, Yul4] extendedsome results in Bat and Su ([3]) to real valued independent but not necessarily identicallydistributed case. The main purpose of this paper is to extend the results of Yu[4] to B-value…     

A STACKELBERG DIFFERENTIAL GAMES SOLUTION TO A PROBLEM OF OPTIMAL INTERTEMPORAL INVESTMENT AND TAX RATE DESIGN

Using the Stackelberg differential games(SDG) theory, we quantitatively study a problem of optimal intertemporal investment and tax rate design. Under some appropriate assumptions, the open-loop Stackelberg equilibrium solutions are obtained. Equilibrium solutions show that: 1. The optimal strategies derived from differential game and unilateral optimal control approaches are different; 2. It is not always the best strategy for the government to use a constant tax rate over the whole time period; 3. The admissible size of tax rate adjustment may have great effect on the government's optimal strategy; 4. SDG approach has no significant effect on the firm's optimal investment strategy.     

UPPER AND LOWER SOLUTIONS METHODS FOR EXISTENCE OF PERIODIC SOLUTIONS OF DUFFING EQUATION

1.IntroductionandNotationsInthispapertwestudytheexistenceofsolutionstothefollowingperiodicboundaryvalueproblemforthesecondorderDuffingequationwheresisarealparameter,g:[0,TIxR~RisaCarath6odoryfunctionandkER\{0}.Werecall(forexample,see[1])thatg:[0,TIxR~RiscalledaCarath6odoryfunctionifg(.,x)ismeasurableforallxERandg(t,.)iscontinuousfora.e.tE[0,TI.Theexistenceproblemfor(1.1)--(1.2)byusingtheupperandlowersolutionsmethodhasbeenstudiedbyFabryetal.in[2]foramoregeneralcasewhereacontinuousdampin…     

具有结盟限制的合作对策的加权Shapley值

现实生活中,联盟的形成通常是有约束的,而且可行联盟的结构是无规律的,此类问题可以用具有结盟限制的合作对策模型来描述.本文研究了结盟有限制而且局中人具有权重的合作对策的收益分配方案,并基于收益分配方案进行了联盟稳定性分析.因为联盟红利可以描述为联盟形成获得的额外收益,因此本文将联盟红利以局中人权重为比例进行分配,定义了加权Shapley值.然后,用两种公理体系,即分支有效性与比例公平性,有效性与加权平衡贡献性,刻画了该加权Shapley值,并讨论了各公理之间的关系.同时,基于加权Shapley值对联盟稳定性进行了分析并建立了数学模型,得到了一些有趣结论,并发现加权Shapley值满足非本质联盟可去性、无关支撑性和关联性.最后,以指派对策为例,表明具有结盟限制的合作对策模型的实用性以及其加权Shapley值的有效性.     

EXISTENCE OF NONTRIVIAL SOLUTIONS FOR CRITICAL SEMILINEAR BIHARMONIC EQUATIONS

ＥＸＩＳＴＥＮＣＥＯＦＮＯＮＴＲＩＶＩＡＬＳＯＬＵＴＩＯＮＳＦＯＲＣＲＩＴＩＣＡＬＳＥＭＩＬＩＮＥＡＲＢＩＨＡＲＭＯＮＩＣＥＱＵＡＴＩＯＮＳ￥ＧＵＹｏｎｇｇｅｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＳｙｓｔｅｍｓＳｃｉｅｎｃｅ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅ...     

部分高铁氧体H面波导Y结环行器的电磁场理论分析

本文对部分高铁氧体H面波导Y结环行器进行了严格的三维场理论分析,经数值计算,得到了许多有用的设计数据、曲线和结论,在理论分析的基础上还进行了实验,实验结果证明了理论分析的正确性。     

c个修理工同步多重休假的k/n(G)表决可修系统

本文首次将"多个修理工同步多重休假"规则引入到c个修理工的k/n(G)表决可修系统中,在假设部件的工作寿命、故障后的修理时间和修理工的休假时间 分别服从参数λ(>0)、μ(>0)和θ(>0)的负指数分布下,利用拟生灭过程 和矩阵几何解方法,讨论了在稳态下系统处于各状态的概率分布,以及一些刻画系统性能的可靠性指标 和排队指标,如系统的稳态可用度、稳态故障频度和故障部件的等待修理时间等,并且讨论了四种特殊情况: 1) c=1,θ→+∞; 2) c=1,k=1,θ→+∞; 3) c=1,k=n,θ→+∞; 4) c=1,k=n-1,θ→+∞.最后给出了在c=2,n=6,k=3,λ=1/10,μ=1/5,θ=1/2的数值计算例子.     

ON A CLASS OF ANISOTROPIC DIFFUSION EQUATIONS

ＯＮＡＣＬＡＳＳＯＦＡＮＩＳＯＴＲＯＰＩＣＤＩＦＦＵＳＩＯＮＥＱＵＡＴＩＯＮＳＯＮＡＣＬＡＳＳＯＦＡＮＩＳＯＴＲＯＰＩＣＤＩＦＦＵＳＩＯＮＥＱＵＡＴＩＯＮＳ￥ＧＡＯＨａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＦｕｄａｎＵｎｉｖｅｒｓｉｔ...     

电力竞价博弈中的信息结构

分析在电力竞价博弈中, 参与者一方如何主动利用需求信息来提高自己的长期利润, 比较不同信息结构如何影响博弈的均衡结果. 假定厂商2 根据前期边际利润及当期需求信息来调整当期的发电量, 厂商1 则利用厂商2 在策略方面的这一信息来优化自己的策略, 以使得长期利润达到最大. 研究表明, 与以往厂商2 单纯利用前期边际利润的旧的信息结构相比, 厂商2 在新的信息结构下的利润将增加, 而厂商1 的利润将减小; 静态古诺模型与单步动态博弈下的利润仍将高于新的信息结构下厂商2的利润, 但低于厂商1 的利润. 同时, 还对不同信息结构下均衡解的其它主要特点进行了分析, 并指出了数值仿真中应当注意的问题.     

Variable Structure Control of Distributed Parameter Systems and Application to the System of Heat Process

ＶａｒｉａｂｌｅＳｔｒｕｃｔｕｒｅＣｏｎｔｒｏｌｏｆＤｉｓｔｒｉｂｕｔｅｄＰａｒａｍｅｔｅｒＳｙｓｔｅｍｓａｎｄＡｐｐｌｉｃａｔｉｏｎｔｏｔｈｅＳｙｓｔｅｍｏｆＨｅａｔＰｒｏｃｅｓｓＺＨＡＯＷｅｎｒｏｎｇＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ...     

PARAMETER-UNIFORM FINITE DIFFERENCE SCHEME FOR A SYSTEM OF COUPLED SINGULARLY PERTURBED CONVECTION-DIFFUSION EQUATIONS

A coupled system of singularly perturbed convection-diffusion equations is considered. The leading term of each equation is multiplied by a small positive parameter, but these parameters may have different magnitudes. The solutions to the system have boundary layers that overlap and interact. The structure of these layers is analyzed, and this leads to the construction of a piecewise-uniform mesh that is a variant of the usual Shishkin mesh. On this mesh an upwind difference scheme is proved to be almost first-order accurate, uniformly in both small parameters. We present the results of numerical experiments to confirm our theoretical results.     

THE RANKINGS OF CONTROL SYSTEMS AND APPLICATIONS

The notion of ranking was initiated into control theory by Glad a few yearsago. In this paper we mainly discuss one kind of rankings and study its invarianceproperties. This kind of rankings is closely related to the structure algorithm. The relationsbetween invariants of this kind of rankings and the invariants given by other studies, e.g.the invertibility indices of a system and so on, are examined. As applications of rankings,we deal with some well-known problems in "ranking technique". In this paper we mainlyintroduce a new method rather than solve new problems.     

基于递阶优化算法的一类两层规划问题的解法

提出一种基于分解协调的两级递阶结构优化算法来求解两层规划问题。通过设计解耦变量,两层规划问题被分解成若干相互独立的易于在结构的第一级求解的子问题。而结构的第二级是调整解耦变量使各子问题的解得以改善。算法以一种迭代的方式使第一级求得的子问题的解不断协调,最终达到两层规划的解。算例表明该算法是可行且有效的     

STABILITY OF STEADY－STATE SOLUTIONS OF THE COMPETITION MODEL IN THE CHEMOSTAT

ＳＴＡＢＩＬＩＴＹＯＦＳＴＥＡＤＹ－ＳＴＡＴＥＳＯＬＵＴＩＯＮＳＯＦＴＨＥＣＯＭＰＥＴＩＴＩＯＮＭＯＤＥＬＩＮＴＨＥＣＨＥＭＯＳＴＡＴ￥ＷＵＪｉａｎｈｕａ（Ｘｉ＇ａｎＩｎｓｔｉｔｕｔｅｏｆＨｉｇｈｗａｙ，Ｘｉ，ａｎ７１００６４，Ｃｈｉｎａ）ＬＩＹａｎ...     

基于多重休假的min(N,V)-策略M/G/1排队系统的队长分布

运用全概率分解技术和拉普拉斯变换工具，研究了基于服务员多重休假的min（N，V）-策略M/G/1排队系统，其中N是预设的休假终止的门限值.讨论了从任意初始状态出发队长的瞬态分布，获得了队长瞬态分布的拉普拉斯变换的递推表达式和稳态队长分布的递推表达式，同时求出了附加队长分布的显示表达式.进一步讨论了当休假时间V分别服从负指数分布和定长分布P{V=T}=1，以及当N=1，N→∞，P{V=0}=1与P{V=∞}=1时的特殊情形.最后，通过数值实例阐述了获得便于计算的稳态队长分布的表达式在系统容量设计中的重要价值.     

养老基金管理的常方差弹性模型及Legendre 变换2对偶解法

文章主要为待遇预定制养老基金的管理建立常方差弹性(CEV)模型,给出了相应的非线性Hamilton-Jacobi-Bellman偏微方程,应用Legendre变换将其转化为线性偏微方程,建立对偶问题.通过对偶问题的求解,从而求得原问题的精确解析解,确定风险资产和无风险资产的投资比例,以及养老金缴费水平,最终实现养老基金管理的最优资产配置和最低缴费水平.     

OPTIMAL CONTROL OF A CLASS OF DISTRIBUTED PARAMETER DELAY SYSTEMS

1.IntroductionManyphysicalsystems,suchajsthemodynamics,electrodynamics,populationbiology,aregovernedbydifferentialequations,integrodifferentialequationsormoregenerallyfunctionaldifferentialevolutionequationsonBanachspace.Associatedoptimalcontrolprobl...