A sequential model for cracking down on street markets for illicit drugs

This paper develops a sequential decision-making model for assisting law enforcement officials in allocating resources during a crackdown operation on illicit drug markets. The sequential crackdown model (SCM) considers a probabilistic framework, where the probability of incarceration of a dealer and the probability of dealing are modeled as a function of the size of a drug market, crackdown enforcement level, drug dealer's financial hardship, and other market characteristics.The model was developed and tested in consultation with enforcement officials from Philadelphia, PA and Camden, NJ. We present a detailed, step-by-step implementation scheme for updating parameters on each day of the crackdown. Parameter estimation along with examples of model usage is provided. Through these examples, we illustrate how the SCM could be helpful in understanding the response of illicit drug markets to various enforcement strategies. We further show conditions under which an alternating crackdown policy (referred to as a crackdown-backoff) or a consistent use of maximum possible enforcement would be optimal strategies for managing a drug crackdown operation. Within the context of the model and parameter estimates, we show that a much quicker and less costly collapse could be implemented if the available enforcement resources are increased. Finally, the model provides possible conditions under which a crackdown operation would be unsuccessful in eliminating a drug market.     

一种产品生产规划模型

在对供应链中运输、库存、产品生产计划分析的 基础上,提出了一种解决厂家产品生产规划的混合整数规划 模型。     

长期筹资科学化的初步探索--构建最佳资本结构模型

助计算机用定量方法快速有效的解决长期筹资决策问题是知识经济时代对企业的必然要求。最佳资本结构模型用计算机运筹学的方法来决策不同筹资方式的最优筹资额，以帮助企业实现长期筹资目标同时也是财务管理最终目标——企业价值最大化。     

A note on the determination of A-optimal type block designs under fixed and mixed effects models

In this paper, we consider the problem of estimating a selected set of contrasts between v treatments using a block design consisting of b blocks of size k. Traditionally, the construction of A-optimal block designs for such situations has been carried out assuming a fixed effects model. In this paper, we show that A-optimal designs constructed under a fixed effects model are robust in the sense that these designs have maximal minimal efficiency when considered among all available designs and under all possible mixed effects models. AMS 1991 subject classifications: Primary 62K05; Secondary 62K10     

两个销售商Bertrand竞争下的供应链需求信息共享

考虑包含一个上游制造商和两个下游销售商的单周期供应链系统。销售商销售不同质的产品且分别拥有关于需求的私有信息。他们之间进行基于价格的Bertrand竞争。建立了三阶段博弈模型，并计算出均衡结果。最后通过模型结果分析需求信息共享前后期望利润的变化，提出了制造商激励销售商其享需求信息的策略。结果表明销售商的需求信息共享在一定条件下是可以很好地实现的。     

数据挖掘在信用风险管理中的应用

本文详细分析了在现代信用风险管理中不同方法对数据质量的要求,并在此基础上提出采用数据挖掘方法改进数据质量、提高计算精度的建议,供我国金融机构信用风险管理之借鉴。     

基于实物期权法对R&D项目价值评估的研究——对布莱克-舒尔斯定价模型的改进

针对R&D项目投资的特点,探讨了采用布莱克一舒尔斯期权定价模型对R&D项目价值评估可能存在的缺陷,并提出一种改进方法,即将决策树和布莱克一舒尔斯定价模型结合运用,因为决策树能够模拟研发项目的阶段性决策过程,考虑到多个离散型不确定性因素的相关性,模拟并计算出对决策路径依赖的现金流,因此能克服纯粹使用布莱克一舒尔斯公式的不足,在考虑多个不确定性因素的影响下,实现对多阶段R&D项目价值的评估,作出正确的投资决策。     

竞争条件下公司投资策略的期权博弈

文章认为在未来不确定的条件下投资主体可以通过推迟投资获取新的信息,减少部分关于投资的不确定性,因此,未来的不确定性隐含着推迟的期权,文章运用博弈理论分析了竞争条件下公司间的投资策略的期权博弈。     

基于企业物流仓储信息系统模型设计的研究

研究了企业物流仓储信息化逻辑流程和仓储物流企业信息模型设计及运转效率。     

两个仓库的变质性物品的库存管理

建立了周期性补充的单一变质性物品（比如粮食、水果等）存贮在两个仓库中的确定性库存模型，对最优解的求解程序进行了讨论，最后举例进行了证明。