带插值的自适应网格重构算法求解带移动热源的反应扩散方程的理论分析

本文研究一个带插值的网格重构算法求解一类带移动热源的反应扩散方程. 算法包括两步: 第一步是用旧时间网层上的计算解计算新时间层上的空间网格; 第二步是使用有限差分方法在新时间层 空间网格上离散方程, 并且将旧时间层上计算解的插值作为初始值. 对于时间, 我们获得了一阶收敛结果. 对于空间, 我们证明了使用线性插值算法的一阶收敛性和使用二次插值算法的二阶收敛性. 数值例子肯定了本文的理论结果.     

总体随机搜索算法的收敛性及计算效益

本文从理论上揭示相当广泛的一类总体随机搜索算法的计算效益差的问题. 设F(x)在R~n上连续,?是一族n维概率分布;设已有当步点x_k,算法在当步迭代开始时从?中任意取一个分布,自该分布随机产生向量ξ作为当步搜索方向,根据x_k和ξ决定下一点x_(k+1).这样可形成极广的一类算法.又设水平集     

基于有向加权网络的价格传导时滞模型

传统的投入产出价格模型利用矩阵描述并分析价格传导过程.因矩阵表述方式属二维模型,故而无法反映价格随时间变化的动态关系.利用有向加权网络描述各产业部门及部门间的价格传导关系,并将时间维度引入构建了价格传导网络模型,考察价格传导时滞的影响.与现有投入产出价格模型相比,模型具有以下三个优势:一是可计算任意时刻的价格传导波动,而传统投入产出价格模型只是该模型在价格传导时间趋向无穷时的特例;二是模型考虑了各部门不同的价格传导时滞的影响,对价格传导过程描述更加精确;三是该模型不受二维矩阵算法的限制,计算复杂度低,易于仿真模拟.     

一个带固定步长的ODE型算法

提出了一种新的求解无约束优化问题的ODE型方法,其特点是:它在每次迭代时仅求解一个线性方程组系统来获得试探步;若该试探步不被接受,算法就沿着该试探步的方向求得下一个迭代点,其中步长通过固定公式计算得到.这样既避免了传统的ODE型算法中为获得可接受的试探步而重复求解线性方程组系统,又不必执行线搜索,从而减少了计算量.在适当的条件下,还证明了新算法的整体收敛性和局部超线性收敛性.数值试验结果表明:提出的算法是有效的.     

空间随机行走比对问题的动态规划算法

受计算生物学中两个蛋白质结构比对问题的启发,定义了三维空间随机步以及两个随机步同构等的概念.研究了步长为k的随机步非同构意义下的个数.最后提出了两个非同构随机步对齐的优化问题,通过研究随机步的同构,采用动态规划给出了将一个随机步对齐到另一个随机步所需最少的操作步数的算法.     

高校应用数学学报第21卷(2006年)B辑(英文版)第3期目次和提要

面对成比例交易成本的情况下外汇期权的定价李淑锦1,2李胜宏1(1.浙江大学数学系;2.江苏技术师范学院)该文的目的是考察在交易外国货币时有成比例交易成本存在的情况下,如何寻找写在汇率上的欧式看涨期权的通用保守价格的金融问题,并且以最大化投资者的期望效用为基础,提出了一种计算外汇期权的保守买卖价格的方法.期权的价格可以从投资者的基本组合选择问题中确定,不需要去求解包含期权收益于最终的值函数这样一个复杂的优化问题.对于指数效用的情况采用马尔可夫链近似,数值化地给出了这种期权的价格.数值化的结果表明,期权价格的界几乎不依…     

一类线性约束矩阵不等式及其最小二乘问题

本文主要考虑一类线性矩阵不等式及其最小二乘问题,它等价于相应的矩阵不等式最小非负偏差问题.之前相关文献提出了求解该类最小非负偏差问题的迭代方法,但该方法在每步迭代过程中需要精确求解一个约束最小二乘子问题,因此对规模较大的问题,整个迭代过程需要耗费巨大的计算量.为了提高计算效率,本文在现有算法的基础上,提出了一类修正迭代方法.该方法在每步迭代过程中利用有限步的矩阵型LSQR方法求解一个低维矩阵Krylov子空间上的约束最小二乘子问题,降低了整个迭代所需的计算量.进一步运用投影定理以及相关的矩阵分析方法证明了该修正算法的收敛性,最后通过数值例子验证了本文的理论结果以及算法的有效性.     

我国认股权证价格偏误的实证研究——以中化CWB1为例

我国权证市场是一个新兴市场,权证市场价格与理论价格长期存在较大偏离.本文以中化CWB1为例,首先运用修正的Black-Scholes公式计算权证的理论价格,证明权证价格偏误的存在主要不来源于模型设定误差,而是与标的股票价格相关.再运用计量经济学的方法讨论权证价格偏误和标的股票价格的协整关系,并建立误差修正模型以定量地描述二者之间的短期波动关系.最后从理论上分析我国权证市场的发展现状和导致价格偏误的深层次原因.     

基于LSMC模型的煤炭资源价值定价研究

煤炭资源价值定价可以抽象为一种美式期权定价问题.最小二乘蒙特卡洛模拟(LSMC)方法是解决美式期权定价问题的一个有效途径.详尽地分析了Cortazar等人的基于资源价格、利率和便利收益随机变动的三因素定价模型,利用向量Ito定理提出了三因素模型中价格、利率和便利收益变量的递推公式.对LSMC方法原理进行了细致的阐述,总结出实现LSMC方法的完整过程,并在Matlab环境下编制了LSMC算法实现程序,进行算例计算.算例结果表明,LSMC方法用于资源定价是有效可靠的.研究为煤炭资源价值定价提供了一个完整具有可操作性的工具.     

可展曲面上的曲线展平线的一般计算方法

生产实践中,常常遇到可展曲面上的曲线的展平线的计算问题.工人师傅和技术人员针对具体问题创造了许多有效的近似方法.本文在实践的基础上,根据微分几何里等距对应理论给出一个一般的计算方法,并分别就可展曲面的三种类型,即柱面、锥面和切线曲面加以讨论和说明.     

Profit allocation games in supply chains

The paper considers a supply chain where a number of agents are connected in some network relationship. Game theory is a very powerful framework for studying decision making problems, involving a group of agents in a supply chain. Allocation games examine the allocation of value among agents connected by a network. The ongoing actions in the supply chain are a mix of cooperative and non-cooperative behavior of the participants. The paper proposes a two-stage procedure for profit allocation based on combination of non-cooperative and cooperative game approaches. In the first stage, retailers meet customer price-dependent stochastic demand and seek to maximize total profit from the sale. Retailers are trying to align goals with producers on a contract basis and share the total profit with them. In the second stage, the cooperating producers allocate individual profits.     

An integrated queuing and multi-objective bed allocation model with application to a hospital in China

In this paper, a multi-objective decision aiding model is introduced for allocation of beds in a hospital. The model is based on queuing theory and goal programming (GP). Queuing theory is used to obtain some essential characteristics of access to various departments (or specialities) within the hospital. Results from the queuing models are used to construct a multi-objective decision aiding model within a GP framework, taking account of targets and objectives related to customer service and profits from the hospital manager and all department heads. The paper describes an application of the model, dealing with a public hospital in China that had serious problems with loss of potential patients in some departments and a waste of hospital beds in others. The performance of the model and implications for hospital management are presented.     

Constrained equilibrium in a bidding problem

There are a number of situations where firms vie for some constrained total quantity by bidding individual quantities but where the allocation is determined on a ‘pro-rated’ basis. One such example is a licenses-on-demand method of import quota allocation. Bidders are constrained to bid at most the total quantity, and if the sum of all bids exceeds this total, the awards are granted proportional to the fractional amounts that the bidders request. In this note, we identify the (Nash) equilibrium of the model, present some examples, and do a sensitivity analysis of the bids as the total amount available changes. We also look into changes of the bids when a new participant enters the bidding process. In an economic context, such allocation methods are shown to be biased in favor of the least efficient firms.     

最优绩效分配的多目标优化方法

如何体现某种程度的激励并兼顾公平性是绩效分配问题研究的关键之一. 基于考核对象的个体差异性, 对考核对象进行分类处理, 通过引入以体现激励程度的控制参数和所有考核对象的基础工作量为变量的分值转化函数与满意度函数, 建立以所有考核对象的总体满意度的最大化和考核对象的满意度尽可能均衡为目标的多目标优化模型. 进而利用多目标优化模型的epsilon-约束标量化方法证明了弱有效解的存在性. 作为其应用, 研究了某高校教师的最优绩效分配问题.     

Aggregate production planning for process industries under oligopolistic competition

We consider a competitive version of the traditional aggregate production planning model with capacity constraints. In the general case, multiple products are produced by a few competing producers (oligopoly) with limited capacities. Production quantities, prices and consequently profits depend on production and allocation decisions of each producer. In addition, there is competition for the raw material whose supplies are limited, and where prices reflect these limitations. Such situations have recently occurred in several process industry settings including petro-refining, petrochemicals, basic chemicals, cement, fertilizers, pharmaceuticals, rubber, paper, food processing and metals. We use a successive “Bertrand–Cournot” framework to address this problem and to determine optimal production quantities, prices and profits at the producers and at the raw material supplier. Our analysis allows a new way to understand and evaluate the marginal value of additional capacity when there is competition for the market and raw materials.     

Single-machine group scheduling with deteriorating jobs and allotted resource

In this paper, we consider single-machine scheduling problems with deteriorating jobs and resource allocation in a group technology environment. In the proposed model of this paper the actual processing time of a job depend on its starting time and the amount of resource allocated to it, and the actual setup time of a group depend on its starting time and the amount of resource allocated. Deterioration effect and two resource allocation functions are examined for minimizing the weighted sum of makespan and total resource cost. For the linear resource allocation function and the convex resource allocation function, we show that the problem remains polynomially solvable under certain conditions.     

Quadratic model for allocating operational budget in public and nonprofit organizations

We develop a quadratic model for allocating operational budgets in public and nonprofit organizations. The allocations for each organizational unit have lower and upper bounds. The objective function is to minimize the weighted sum of the quadratic deviations of each allocation from its bounds. The optimal allocations are mostly around the midpoint between the bounds. A simple algorithm is presented to derive the solution. The new quadratic model is compared to the familiar linear model for budget allocation, which almost always, provides extreme allocations on the bounds: for some units on the upper bound, while for others, on the lower bound. We perform sensitivity analyses, and resolve special cases of the model with closed form solution. Moreover, we show various properties of the quadratic budget allocation model and prove that its fairness index is higher than that of the linear model. The model, with its variants, was actually used for allocating budgets in various university setups; some examples are presented here.     

基于损耗率和需求不确定情况下的订购批量

库存管理模型在现实生活中有着广泛的运用。然而,在实际生活中,由于种种不确定性原因的影响,使得经典的确定型的EOQ模型的运用越来越不符合现实的需要;本文将需求和损耗率看成模糊数的同时,将物品的销售价格分成两部分来进行处理,即:没有损耗的产品以一种较高价格出售,对于有部分损耗的产品则按较低的价格出售;采用概率论置信区间估计的方法构建模糊变量的波动区间,构建使得总的利润达到最大的模糊库存模型,并利用三角模糊数、符号距离的方法以及最优化理论进行处理,得出满足条件的最优订购批量。最后,给出了模型分析和算例分析;通过分析,我们发现模糊库存模型的优点在于它自生所具有的不确定性;从数据上看,模糊库存模型比经典的库存模型更能反映出实际情况。     

Information resource planning for a health-care system using an AHP-based goal programming method

This paper presents a goal programming (GP) model which aids in allocating a health-care system's information resources pertinent to strategic planning. The model is developed based on the data obtained from a major health-care system in the United States. The overall objective is to design and evaluate a model for effective information resource planning in a health-care system. The proposed model: (1) utilizes a GP approach to reflect the multiple, conflicting goals of the health-care system; (2) employs a GP solution process to reflect multi-dimensional aspects of the resource allocation planning; and (3) allows for some degree of flexibility of decision-making with respect to resource allocation. The goals are decomposed and prioritized with respect to the corresponding criteria using the analytic hierarchy process (AHP). The model result is derived and discussed. This GP model facilitates decision-making planning process and managerial policy in health-care information resources planning and similar planning settings.     

Optimal Co-Operative Advertising Decisions in Direct-Mail Operations

This paper considers optimization of vertical co-operative promotion decisions in a direct mail operation. After presenting our model, we demonstrate that it is likely that a vertical co-operative direct mail promotional effort can result in a situation in which both the direct mailer and the manufacturer increase profits, compared with the situation where the direct mailer makes ‘optimal’ direct mail decisions without regard to any involvement with the manufacturer. We next show that the manufacturer can optimize his own profitability by agreeing to a specific (quantitatively determined) contribution to mail order costs. Finally, we illustrate how the manufacturer and direct mailer can co-operate (move away from their individual optimal decision variables), reaching an integrative, rather than a distributive solution, and jointly set the values of these decision variables, so that the total profit generated by the operation is higher than the sum of the individual profits of the two parties.