制度因素对我国国际储备的惯性影响

本文在缓冲储备理论中引入了习惯形成因素,在BS模型的基础上构造了一个既包括国际收支波动性和机会成本同时又考虑了习惯形成因素的动态调整模型。利用1996-2009年间中国国际储备的月度数据进行了实证分析,结果表明:(1)一国国际储备是国际收支不确定性和机会成本的函数,它们三者之间存在长期均衡关系,也就是说BS理论预期模型在经过适当的修正后对中国外汇储备规模的实证研究是适用的。(2)习惯形成参数越大,以往的制度因素形成的惯性对后期储备积累的影响就越大,国际收支不确定性以及机会成本对储备的影响也越小,并且这个惯性一旦形成,很难立刻改变。(3)正是由于考虑了习惯形成因素,外汇储备规模关于国际收支不确定性的弹性以及机会成本的弹性更接近于BS模型的理论预期值。     

团队成员交换、社会因素策略与新员工社会化

团队工作方式在组织中日益普遍,团队成员成为影响新员工社会化的重要因素。探讨团队成员交换对新员工社会化结果的影响及其作用机制,尤其是社会因素策略这一组织社会化策略在其中的中介作用,选取201个入职时间在一年半以内的销售人员为调查样本,运用结构方程模型路径分析方法对研究模型进行检验。研究结果表明,团队成员交换对新员工社会化结果产生显著影响;新员工感知的社会因素策略在团队成员交换与任务掌握、角色清晰、工作满意度之间起部分中介作用,在团队成员交换与离职倾向之间起完全中介作用。这表明高质量的团队成员交换关系可以促进新员工感知更多来自组织的正向社会支持以及组织内部人的角色模范作用,最终帮助他们成功社会化。     

考虑噪声因子的参数和公差经济性设计策略

基于并行工程思想的参数和公差经济性设计,以成本为优化目标来确定最优的设计参数和公差范围.就并行参数和公差设计通过双响应曲面均值和方差模型实现其稳健性,本文提出了包含噪声因子的响应曲面建模策略,应用这一模型将参数和公差同时优化.该参数和公差经济性设计优化模型以质量损失和制造成本之和为目标函数,以过程方差置信域为约束.实例结果表明,在双响应曲面方法中,对均值设置偏倚量比其刚性约束具有较大的成本优势,在不降低稳健性的前提下引入偏倚可以降低成本.面向噪声因子的设计策略其成本低于基于双响应的有偏倚的设计,说明考虑噪声因子的设计是最有效的.     

Foodborne Exposure to Pesticides and Methylmercury in the United Arab Emirates

As part of a comprehensive environmental health strategic planning project initiated by the government of Abu Dhabi, we assessed potential dietary exposure in the United Arab Emirates (UAE) to methylmercury (in seafood) and pesticides (in fruits and vegetables) above international guideline levels. We present results for the UAE population by age, gender, and body mass index. Our results show very low daily risks of exposure to pesticides in fruits and vegetables at levels exceeding WHO guidelines even under the conservative assumption that no pesticides are removed during washing and food preparation. Thus, exposure to pesticides on fruits and vegetables does not appear to be a major public health concern in the UAE. The chances of exposure to methylmercury in seafood are much higher; our model estimates a mean 1 in 5 daily risk of exceeding the FAO/WHO provisional tolerable weekly intake. However, great caution should be used in interpreting these results, as we analyzed only the risks and not the substantial benefits of fish consumption. In fact, previous studies have demonstrated that exposure to the n‐3 polyunsaturated fatty acids in fish can increase IQ in developing children, and it can substantially decrease the risk in adults of coronary heart disease and stroke. Further research is warranted to compare the risk of Me‐Hg exposure from fish to the nutritional benefits of fish consumption in the UAE and to determine appropriate methods to communicate risk and benefit information to the UAE population.     

Pricing Decisions During Inter‐Generational Product Transition

How should companies price products during an inter‐generational transition? High uncertainty in a new product introduction often leads to extreme cases of demand and supply mismatches. Pricing is an effective tool to either prevent or alleviate these problems. We study the optimal pricing decisions in the context of a product transition in which a new‐generation product replaces an old one. We formulate the dynamic pricing problem and derive the optimal prices for both the old and new products. Our analysis sheds light on the pattern of the optimal prices for the two products during the transition and on how product replacement, along with several other dynamics including substitution, external competition, scarcity, and inventory, affect the optimal prices. We also determine the optimal initial inventory for each product and discuss a heuristic method.     

Inventory Policy with Parametric Demand: Operational Statistics,Linear Correction,and Regression

In this paper, we consider data‐driven approaches to the problem of inventory control. We first consider the approach of operational statistics and review related results which enable us to maximize a priori expected profit uniformly over all parameter values, when the demand distribution is known up to the location and scale parameters. For the case of the unknown shape parameter, we first suggest a heuristic approach based on operational statistics to obtain improved ordering policies and illustrate the same for the case of a Pareto demand distribution. In more general cases where the heuristic is not applicable, we suggest linear correction and support vector regression approaches to better estimate ordering policies, and illustrate these using a Gamma demand distribution. In certain cases, our proposed approaches are found to yield significant improvements.     

数字货币时代的商业模式讨论--基于双案例的比较研究

本文运用对比案例分析法,选取Steemit论坛和知乎论坛作为分析对象,探究了使用数字货币与否对同一行业组织的商业模式及其创新有什么影响。本文以商业模式画布为蓝本,通过对比数字货币背景下商业模式在价值主张、价值创造、价值传递、价值网络和价值实现五个方面的差异,探究数字货币时代下商业模式的创新影响,以及商业模式不同价值元素间新的构成秩序。本研究分析了选取案例商业模式中的不同对应元素,并给出了以下三个针对数字货币和商业模式的新命题:第一,数字货币在价值创造过程中联结利益主体;第二,数字货币起到了模糊价值网络边界的作用,从而促进构成新的治理模式;第三,使用数字货币可以在价值实现过程中完成利润重新分配。最后,文章认为数字货币情景下商业模式中不同价值元素的交互关系,呈现出以客户关系为核心的共同价值创造和共同价值实现的新秩序。     

基于Agent的情感劝说的决策过程及模型研究

Agent具有情感后进行的劝说决策会更加理性,而现有研究还不够全面深入。针对此问题,首先结合形式逻辑理论,定义了基于Agent的情感劝说及其决策过程,并将基于Agent的情感劝说的决策过程划分为评价情感劝说行为、更新情感劝说状态、调整情感劝说目标、产生情感劝说行为四个阶段;其次针对这四个阶段,结合OCC情感模型和PAD心情模型,运用多属性效用理论,引入情感淡化因子和情感评价因子,定义了Agent情感触发函数,建立了八种Agent基本情感与劝说目标的映射关系,将Agent的情感劝说行为分为奖励型、申辩型、威胁型和反辩型四类,分别构建了相应的决策模型,从而构成了更加完整和合理的基于Agent的情感劝说的决策过程模型;最后通过算例证明了模型的合理性和有效性。     

供需不确定条件下基于CVaR的零售商库存鲁棒优化模型

在经典报童模型下考虑供应和需求不确定性,研究了具有风险厌恶的零售商库存优化问题。采用条件风险值(CVaR)对库存绩效进行度量,构建了基于CVaR的零售商库存运作模型;在此基础上,考虑上游供应商供货能力和下游市场需求不确定性,并采用一系列未知概率的离散情景进行描述,给出了供需不确定条件下基于CVaR的零售商库存鲁棒优化模型。进一步,采用区间不确定集对未知情景概率进行建模,给出了基于最大最小准则的鲁棒对应模型。针对同时考虑供需不确定性导致的模型非凸性,采用标准对偶理论将其转化为易于求解的数学规划问题。最后,通过数值计算分析了不同风险厌恶程度和不确定性程度对零售商库存决策以及库存绩效的影响。结果表明,供需不确定性的存在虽然会导致零售商库存绩效损失,但损失值较小。特别地,依据文中模型得到的鲁棒库存策略在多数情况下能够保证零售商获得更优的库存绩效。此外,不确定性和风险厌恶程度的增加虽然会影响零售商库存决策和运作绩效,但在同等风险厌恶态度下,随着不确定性程度的增加,基于文中方法得到的鲁棒库存策略仍能确保零售商获得理想的库存绩效,表明文中所建模型在应对供需不确定性方面具有良好的鲁棒性。