参激白噪声作用下蔡电路的脉冲控制

考察了参激白噪声和脉冲信号联合作用下蔡电路的渐近P阶矩稳定性问题,得到该随机脉冲系统的比较系统,从而可由该确定性比较系统的稳定性得到原随机脉冲系统的渐近P阶矩稳定性.并从理论上得到能使该随机脉冲系统渐近P阶矩稳定的参数取值范围,即在稳定区域内取值的参数组合能够用脉冲方法对该随机蔡电路实现混沌控制.最后用数值仿真验证了理论结果的正确性.     

Designs,Codes and Crypts—A Puzzle Altogether

In this paper we present an algebraic specificationof a puzzle commercially available on the toy market which isclosely related to the area of designs, codes and cryptography.The purpose of this article is to show the different ways ofapproaching the problem of solving this puzzle. An algebraicapproach for finding a solution is given. The seemingly unknowncombinatorial type of this puzzle and the lack of a general theoreticalbackground have stimulated the set-up of this paper to be presentedin this volume.     

On rings whose prime ideals are completely prime

We investigate in this paper rings whose proper ideals are 2-primal. We concentrate on the connections between this condition and related concepts to this condition, and several kinds of π-regularities of rings which satisfy this condition. Moreover, we add counterexamples to the situations that occur naturally in the process of this note.     

冷贮备冗余系统可靠度预计的递归算法

基于贮备科系统的特点,运用折方法得出一种用计算机求冷贮备冗余系统可靠度的方法,并将该计算方法用于两个计算实例。     

A primal–dual algorithm for minimizing a sum of Euclidean norms

We study the problem of minimizing a sum of Euclidean norms. This nonsmooth optimization problem arises in many different kinds of modern scientific applications. In this paper we first transform this problem and its dual problem into a system of strongly semismooth equations, and give some uniqueness theorems for this problem. We then present a primal–dual algorithm for this problem by solving this system of strongly semismooth equations. Preliminary numerical results are reported, which show that this primal–dual algorithm is very promising.     

The Automorphism Group and the Convex Subgraphs of the Quadratic Forms Graph in Characteristic 2

We determine the automorphism group and the convex subgraphs of the quadratic forms graph Quad(n,q),q even.A. Munemasa: A part of this research was completed during this author's visit at the Institute for System Analysis, Moscow, as a Heizaemon Honda fellow of the Japan Association for Mathematical SciencesD.V. Pasechnik: A part of this research was completed when this author held a position at the Institute for System Analysis, MoscowS.V. Shpectorov: A part of this research was completed during this author's visit at the University of Technology, Eindhoven     

Confluent Form of the Multistep ɛ‐Algorithm,and the Relevant Integrable System

In this paper, the confluent form of the multistep ? ‐algorithm is proposed. The molecule solution of this system is derived by using determinantal identities. A new continuous prediction algorithm based on this confluent form is constructed. It also shows that this algorithm is a special case of the extended Lotka–Volterra system.     

Finding GM-estimators with global optimization techniques

In this note we address the problem of finding the GM-estimator for the location parameter of a univariate random variable. When this problem is non-convex but d.c. one can use a standard covering method, which, in the one-dimensional case has a simple form. In this paper we exploit the structure of the problem in order to obtain d.c. decompositions with certain optimality properties in the application of the algorithm. Numerical results show that this general-purpose algorithm outperforms previous ad-hoc methods for this problem.     

An implicit finite difference scheme for the nonlinear size-structured population model

In this paper we consider the "fully nonlinear" size structured population model. We develop an implicit finite difference scheme to approximate the solution of this nonlinear partial differential equation. The convergence of this approximation to a unique bounded variation solution of this model is obtained. Numerical results to an example problem are presented.     

一类一维的辐射流体力学方程组激波的存在性

该文主要讨论一维空间中一类辐射流体力学方程组的激波. 由Rankine-Hugoniot条件及熵条件得此问题可表述为关于辐射流体力学方程组带自由边界的初边值问题. 首先通过变量代换, 将其自由边界转换为固定边界, 然后研究关于此非线性方程组的一个初边值问题解的存在唯一性. 为此先构造了此问题的一个近似解, 然后分别通过Picard迭代与Newton迭代对此非线性问题构造近似解序列. 通过一系列估计与紧性理论得到此近似解序列的收敛性, 其极限即为原辐射热力学方程组的一个激波.     

The vanishing-off subgroup

In this paper, we define the vanishing-off subgroup of a nonabelian group. We study the structure of the quotient of this subgroup and a central series obtained from this subgroup.     

The Lattice of Fully Invariant Subgroups of a Cotorsion Group

In this monograph, we discuss some problems of the theory of Abelian groups. In particular, the lattice of fully invariant subgroups of a cotorsion group is studied in detail. The currently available results related to this topic are presented. The purpose of this monograph is to acquaint undergraduates, senior students, and doctoral candidates with the state of the art in this field.     

The nearest point problem in a polyhedral set and its extensions

In this paper we investigate the relationship between the nearest point problem in a polyhedral cone and the nearest point problem in a polyhedral set, and use this relationship to devise an effective method for solving the latter using an existing algorithm for the former. We then show that this approach can be employed to minimize any strictly convex quadratic function over a polyhedral set. Through a computational experiment we evaluate the effectiveness of this approach and show that for a collection of randomly generated instances this approach is more effective than other existing methods for solving these problems.     

Global BV solution for a non-local coupled system modeling the dynamics of dislocation densities

In this paper, we study a non-local coupled system arising in the modeling of the dynamics of dislocation densities in crystals. For this system, the global existence and uniqueness are available only for continuous viscosity solutions. In the present paper, we investigate the global time existence of this system by considering BV initial data. Based on a fundamental uniform BV estimate and the finite speed of propagation property of this system, we show, in a particular setting, the global existence of discontinuous viscosity solutions of this problem.     

Logic for abstract hoop twist-structures

In this paper, we introduce and study a logic that corresponds to abstract hoop twist-structures and present some results on this logic. We prove the local deductive theorem for this logic and show that this logic is algebraizable with respect to the quasi-variety of abstract hoop twist-structures.     

经济适用房开发过程中政府与开发商的博弈

本文通过对开发商开发经济适用房还是商品房的博弈分析,解释了目前开发经济适用房过程中出现的不合理的现象.找出了问题的根本原因——制度设计,并分析了原因,以期从原因出发设计新的制度.     

A Note On Kalmanson Matrices ∗

In this note we derive an additive characterization of Kalmanson matrices by investigating the cone of this matrix class. With the help of this characterization, a simple proof for a result obtained by Kalmanson (1975) on the symmetric travelling salesman problem is presented. Moreover, this characterization can also be used to generate distance matrices for which the optimal solution is known in advance     

Measuring the strength of trade unions and identifying the privileged groups: A two-dimensional approach and its implementation

Trade unions were important actors in the advanced capitalist countries until the late 1970s, but since the 1980s, union membership is declining. Whether this decline has been homogenous is crucial. Because unions may still have power and non-homogenous decline implies that some groups benefit from this power disproportionately. However, we don’t have instruments to scrutinize this dynamic properly. To fill the gap, this study develops a model that identifies privileged groups within trade unions by informing us about the relative strength of a group within trade unions, the ability of this group to use the union power, and the extent to which union members belonging to the group would advance the interests of the entire group by using this power.     

非齐次Toda晶格的对称,精确解和可积性

研究非齐次Toda晶格，即一类非齐次非线性微分差分方程的对称与可积性。给出了这一类方程的Lie点对称，条件对称和精确解。给出这类方程与Toda晶格之间的可逆点变换，从而表明这一类方程是可积的。     

Global attractability and permanence for a new stage-structured delay impulsive ecosystem

In this paper, a new stage-structured delay ecosystem with impulsive effect is formulated and some dynamical properties of this system is investigated.By using comparison theorem and the stroboscopic technique, we prove the existence of the predator-extinction periodic solution of this system and obtain some sufficient conditions to guarantee the global attractivity of the prey-extinction periodic solution. In the final, we also obtain the permanence of this system. It should be pointed out that the new mathematical method used in this paper can also be applied to investigate such other ecosystems corresponding to both impulsive and delay differential equations.