一般交叉规划与经济均衡模型

本文首先给出了有多个子规划的一般交叉规划模型,然后把它转化为抽象经济模型,并给出其均衡解存在的条件.最后利用一般交叉规划建立了一类非合作型寡头垄断市场的均衡模型.     

一个带产品定价约束的竞争选址双层规划模型及其求解算法

以大型连锁卖场的选址为研究背景,提出了一个在竞争环境下使获利最大的竞争选址定价双层规划模型,其中上层模型做出选址决策,下层模型确定产品的纳什均衡价格.将设施效用引入到模型中,用指数效用函数来刻画顾客的购物行为偏好,首次证明了不合作状态下双方价格均衡解的存在性和唯一性,并给出了求解最优设施点设置方案和价格均衡解的算法思想及数值算例.     

多重嵌套的可计算非线性动态投入产出模型及其平衡增长解

给出多重嵌套的可计算非线性动态投入产出模型,并给出相应的价格、利润率、产出结构、增长率的平衡增长解计算公式.从本文给出的模型可以看出非线性投入产出模型可以有无穷多种不同形式,其中只有1种为众所周知的列昂惕夫线性投入产出模型.本文模型的重要意义在于它是线性投入产出模型与CGE（可计算一般均衡）模型的统一.它既克服了线性投入产出模型资本与劳动不可替代的缺点,又可方便地求解动态CGE的平衡增长解.     

随机广义纳什均衡问题带有条件风险价值约束的确定性模型及其求解方法

主要考虑随机广义纳什均衡问题(SGNEP),由于随机变量的存在,SGNEP通常无解.对此问题,文章首先给出一阶必要性条件并利用NCP函数得到优化模型的目标函数,为降低所得解的"风险",再利用条件风险价值(CVaR)给出约束条件,从而构造出求解SGNEP的一个低风险模型,并将此模型所得解视为SGNEP的解.然而,直接求解该低风险模型可能会遇到两个问题:一是该模型含有非光滑约束,二是目标函数和约束条件包含期望值.考虑到这两个问题,采用光滑化和罚样本均值近似方法提出该模型的近似问题,并进一步给出近似问题最优解的收敛性结果.最后,文章给出数值算例,以验证所提方法的可行性.     

多目标供应链网络平衡模型

针对生产商、零售商和消费群三层决策者问题建立了一个多目标供应链网络均衡模型.给出此模型的均衡条件,并讨论了(弱)均衡解和标量化解之间的关系.最后,给出具体的例子说明此模型.     

一类带有时滞项的种群模型的求解

研究一类带有时滞项的种群模型的求解.首先给出模型在平衡点处的线性化模型,并得到其本征值的显式表达式.然后证明相应的本征向量序列并不构成状态空间的基,但仍得到了模型的解按照本征向量的展开式,且展开式绝对收敛.最后给出解的数值模拟,从理论上和数值上证明解的展开式具有高精度,从而可用其研究解的大时间行为.     

变系数浅水波方程的精确解

均衡作用法给出了一种求非线性发展方程孤波解的有效方法.利用该方法,运用计算机符号计算,求出了变系数的一般浅水波方程的孤子解.     

汽车生产厂家的定价策略博弈模型

讨论了企业在经营管理中的最优化问题,构建了汽车行业在寡头垄断市场中各厂商之间的定价博弈模型.利用统计学中的多元线性回归模型给出两种不同型号汽车的销售量和价格的经验的需求函数关系式,检验了此模型的拟合优度,对其整体显著性的进行了F检验,并对偏回归系数的显著性进行了t检验,探讨了两寡头垄断企业的产品的需求函数为二元线性函数的伯特兰德模型,获得了其纳什均衡解的一般结论,并给出了某两型号汽车的定价博弈的具体均衡结果.     

资源优化配置下的供应链竞争模型研究

本文在供应链竞争的经济背景下,考虑由多条结构异质的供应链构成的竞争模型.供应链在市场需求的推动下以自身利润最大化为决策标准,整合生产工序、分配企业内部资源.本文首先通过市场链的定义分析了供应链间的竞争方式;然后,利用博弈理论以及变分不等式方法,构建了供应链间竞争的均衡模型;进一步,给出了模型解的存在性和唯一性.最后,利用数值算例说明了模型的有效性.     

随机需求下直销多商品流供应链网络均衡模型

建立了随机需求下直销多商品流供应链网络均衡模型,导出了供应链网络达到均衡的条件,它等价于一个有限维变分不等式.通过构建修改拟牛顿法,获得了随机需求下直销多商品流供应链网络均衡模型的解(变分不等式的解),并给出了1个算例,验证了模型的正确性和算法的可行性.     

Algebraic solution to interval equilibrium equations of truss structures

This paper considers a recently proposed interval algebraic model of linear equilibrium equations in mechanics. Based on the algebraic completion of classical interval arithmetic (called Kaucher arithmetic), this model provides much smaller ranges for the unknowns than the model based on classical interval arithmetic and fully conforms to the equilibrium principle. The general form of interval equilibrium equations for truss structures is presented. Two numerical approaches for finding the formal (algebraic) solution to the considered class of interval equilibrium equations are proposed. A methodology for adjusting interval parameters so that the equilibrium equations be completely satisfied is also presented. Numerical examples illustrate the theoretical considerations.     

General financial equilibrium with policy interventions: a variational inequality approach

In this paper a model of general financial equilibrium with policy interventions is introduced, which yields the optimal composition of assets and liabilities in each sector's portfolio, as well as the market prices for each instrument. The policy interventions considered are taxes and price ceilings. The variational inequality formulation of the equilibrium conditions is derived and then utilized to establish existence and uniqueness properties of the solution pattern. An algorithm is proposed for the computation of the problem. Finally, the algorithm is applied to some special utility functions as numerical examples.     

Semi-implicit method for thermodynamically linked equations in phase change problems (SIMTLE)

Thermodynamic coupling of temperature and composition fields in phase-change problems has been a challenge for decades. A compromise has been always desired between numerical efficiency and detailed physical consideration, toward a general scheme. In the present work, a macro–micro numerical method is proposed to link the conservation equations of energy and species with the thermodynamics of the solidification problems. Firstly, the basic structure of the method, simplified with a local equilibrium assumption, is presented. The method is then extended to a multi-phase model, demonstrating a three-phase approach to the solidification of a eutectic binary alloy. Relaxing the limitations imposed by the equilibrium assumption, non-equilibrium and microscale considerations was also included subsequently by a suggested modification to the macroscopic mathematical model. Advantages gained through the general algorithm proposed are concerned with two features of the method; (a) consistency with the energy and species equations. (b) No need of a predefined solidification path; that allows for the usage of raw phase diagram curves and offers simplicity and generality for extension through complex problems (i.e. microscopic, multi-phase or non-equilibrium). A benchmark problem was employed to test the performance of the proposed method in two cases of local equilibrium and Scheil-like solidification. The obtained results were validated in comparison with available semi-analytical solution.     

An algorithm based on a sequence of linear complementarity problems applied to a walrasian equilibrium model: An example

The Walrasian equilibrium problem is cast as a complementarity problem, and its solution is computed by solving a sequence of linear complementarity problems (SLCP). Earlier numerical experiments have demonstrated the computational efficiency of this approach. So far, however, there exist few relevant theoretical results that characterize the performance of this algorithm. In the context of a simple example of a Walrasian equilibrium model, we study the iterates of the SLCP algorithm. We show that a particular LCP of this process may have no, one or more complementary solutions. Other LCPs may have both homogeneous and complementary solutions. These features complicate the proof of convergence for the general case. For this particular example, however, we are able to show that Lemke's algorithm computes a solution to an LCP if one exists,and that the iterative process converges globally.     

中心刚体-外Timoshenko梁系统的建模与分岔特性研究

对于中心刚体固结悬臂梁系统,当不考虑梁剪应力(即Euler-Bernoulli梁)影响时,匀速转动梁的平凡解是稳定的。而对于深梁,有必要考虑剪应力(即Timoshenko梁)的影响,此时其匀速转动平凡解将出现拉伸屈曲。为此采用广义Hamilton变分原理建立了中心刚体固结Timoshenko梁这类刚-柔耦合系统的非线性动力学模型,应用数值方法研究了匀速转动Timoshenko梁非线性系统的分岔特性,以及失稳的临界转速。     

A numerical integrator for a model with a discontinuous sink term: the dynamics of the sexual phase of monogonont rotifera

We present an explicit numerical method especially adapted to approximate the solution of a nonlinear model with a discontinuous sink term: the dynamics of the sexual phase of monogonont rotifera. We show the effectiveness of this numerical technique in the simulation of the dynamics of the solutions. In particular, we show that this method provides a good approximation to the equilibrium solution of the problem. On the other hand, the numerical simulation presented validates the asymptotic behaviour of the numerical solution with regard to the theoretical one.     

Oscillation analysis of θ‐methods for the Nicholson's blowflies model

This paper is concerned with the oscillation of numerical solution for the Nicholson's blowflies model. Using two kinds of θ‐methods, namely, the linear θ‐method and the one‐leg θ‐method, several conditions under which the numerical solution oscillates are derived. Moreover, it is shown that every non‐oscillatory numerical solution tends to equilibrium point of the original continuous‐time model. Finally, numerical experiments are provided to illustrate the analytical results. Copyright © 2015 John Wiley & Sons, Ltd.     

具有非线性传染率和时滞的随机SIQR计算机病毒模型的渐近行为

研究了一类具有非线性发生率和时滞的随机SIQR计算机病毒模型.首先证明了该系统具有唯一的全局正解,然后通过构造适当的Lyapunov函数并利用伊藤公式,分析了该模型的解在无病平衡点附近及地方病平衡点附近的渐近行为,最后通过数值模拟对随机系统解的渐近行为做了进一步的分析并给出了结论.     

A SOLUTION OF A GENERAL EQUILIBRIUM PROBLEM

Under the framework of a real Hilbert space, we introduce a new iterative method for finding a common element of the set of solution of a general equilibrium problem and the set of fixed points of a nonexpansive semigroup. Moreover, a numerical example is presented. This example grantee the main result of the paper.