短保质期变质产品的两次订货策略研究

一类短保质期变质产品,如生鲜蔬菜、水果等,增加其库存展示量能为顾客提供更多的拣选机会,从而刺激顾客增加购买量.对此,在综合分析已有变质库存基本模型的基础上,建立了一个更能准确反映当前存货水平和需求率、变质率的关系的库存模型.考虑到计划期可能不是最优订货周期的整数倍,从一般意义上研究了基于保质期约束和计划期可修正的变质产品最后两次订货策略.结论表明,最优订货周期须超过一个保质期.在计划期的一定变动范围内,订货周期越短越有利于增加利润和增强经营的社会外部性,并在计划期的上界达到最优;超过计划期的合理变动范围,则须将不完整订货周期控制在一个保质期内,且越接近保质期越好,否则随着计划期延长,变质量增加而利润却逐渐降低.     

保鲜投入影响需求的社区生鲜O2O模式选择与协调研究

在由一个生鲜电商和社区零售店组成的生鲜O2O供应链中,生鲜电商可选择批发模式或佣金模式与社区零售店进行合作。本文考虑价格、保鲜投入水平和增值服务水平影响生鲜农产品需求,分别构建批发模式与佣金模式下的供应链博弈模型,分析了不同模式下新鲜度敏感系数对供应链最优决策的影响,探究了生鲜电商的最优合作模式选择问题。针对生鲜电商和零售店可实现合作模式改善的情形,设计了转移支付契约,分析了合作模式改善对定价、服务和保鲜策略的影响。研究表明,当佣金率低于(高于)1/2时,若保鲜效率较低,生鲜电商选择佣金(批发)模式,若保鲜效率较高,生鲜电商选择批发(佣金)模式。当保鲜效率很低且服务效率相对较高时,零售店总是更偏好佣金模式,但其要求的佣金率不宜过高,否则生鲜电商会选择对其次优的批发模式。当保鲜效率和服务效率都较低时,合作模式的改善不仅能实现供应链成员利润改善,还可以使消费者以低价买到优质的生鲜农产品,增加消费者剩余。     

拉动与推动混合供货方式下ATO系统的生产补货策略研究

考虑ATO系统由一个最终产品制造商与两个零部件供应商组成,供应商分别采用拉动式和推动式供货方式向制造商提供零部件,建立了相应的ATO系统生产、补货模型,运用逆向归纳法求得了系统最优解,并进行了理论分析、数值仿真和主要参数灵敏度分析。研究表明：ATO系统中处于主导地位的一方具有先动优势,能获得更多的利润;市场规模的变化对供应商和最终产品制造商利润的影响相同,且影响力与规模大小无关;产品销售价格的变化对企业利润的影响不相同,且销售价格越高影响力越小;生产成本的变化对企业利润的影响不同,对生产成本高的企业影响较大,对生产成本低的企业影响较小。     

面向B2B公共平台的第三方物流服务模式及实施策略

针对B2B电子商务公共平台的物流瓶颈问题,提出了面向B2B公共平台的第三方物流服务模式,分析了其框架结构、组成要素及其特点;并进一步结合业务流程给出了面向B2B公共平台的第三方物流服务实施策略,最后对一个案例进行了分析说明.     

带工期指派的产品服务系统订单随机调度问题研究

针对由一个制造工厂和多个区域服务中心组成的服务型制造企业,研究了考虑生产时间和服务时间均具有随机性且工期可指派的产品服务系统（PSS）订单调度问题。首先以最小化订单提前、误工和工期指派费用的期望总额为目标构建问题的优化模型,然后分析目标函数近似值的最优性条件,据此提出加权最短平均生产时间排序规则,并结合该规则与插入邻域局部搜索设计了启发式算法对问题进行求解,最后通过数值仿真验证算法的可行性和有效性。研究表明,提前费用偏差对PSS订单调度与工期指派决策的影响很小,因此企业管理者无需准确估计库存费用也能制定出比较有效的PSS订单调度策略;而工期指派费用偏差对决策结果的影响非常大,因此企业管理者在决策时必须谨慎估计该项费用。     

考虑订货协调成本与数量折扣的改良品供应链水平协调

在单个供应商与多个销售商构成的二级改良品供应链中,销售商们采用联合补货方式不仅可以分摊订货成本,而且由于订货批量的增加从而更易获得供应商提供的数量折扣合同。建立多个销售商在独立补货与联合补货中的利润水平函数,推导联合补货优于独立补货的充要条件。将销售商之间的联合补货行为转化成多人合作博弈问题,证明博弈具有的基本性质,设计基于博弈核心的利润分配方法。通过数值算例和敏感性分析验证了文中所构建模型的正确性。     

卓越教师培养的有效探索——我国台湾地区“卓越师资培育奖学金计划”述评及启示

当前国际教师教育改革转为以卓越为取向的发展趋势。我国台湾地区的"少子化"问题引发了该区域师资供需失调的矛盾，同时多元化的师资培育模式又导致教师素质不断下降。在此背景下，2006年我国台湾地区推行"卓越师资培育奖学金计划"。该计划旨在提升师资培育过程质量、加强绩效管理、建立完善的奖励与竞争机制，通过实现优胜劣汰来保障实施该计划的各院校取得成效。经过试行与正式实施，该计划的成效整体良好。"卓越师资培育奖学金计划"对新时代卓越教师培养具有一定的借鉴意义，如以奖励与竞争的方式优化卓越师资结构、建立卓越教师培养计划退场机制、改革高校教师教育培养模式，等等。     

LAWYERS IN VENTURE CAPITAL CONTRACTING: THEORY AND EVIDENCE

Real‐world financial contracts are sometimes so complex that it can be difficult to understand their exact payoff consequences. We develop and test a theoretical model of a venture capitalist (VC) negotiating with an entrepreneur who may overweigh or underweigh the payoff consequences of contractual downside protection (DP). A lawyer with expertise in venture capital can inform the entrepreneur about these consequences, but less expert (but otherwise high quality) lawyers cannot. We determine how a VC's decision to include DP is affected by the expected quality of the entrepreneur's project, the entrepreneur's experience, and the VC expertise of his/her legal counsel. We show that the VC's incentive to include unnecessary DP declines in expected project quality. Indeed, for inexperienced entrepreneurs involved with high‐quality projects, VCs prefer that the entrepreneur's counsel has VC expertise. This implies that, when negotiating with inexperienced entrepreneurs, VCs who invest in high‐quality companies should be more likely to negotiate with entrepreneurs who employ lawyers with VC expertise. We document broad empirical support for the model, and provide evidence against competing explanations. (JEL L24, G24, K12, L14, L24)     

POWER APPROXIMATIONS FOR A TWO-ECHELON INVENTORY SYSTEM USING SERVICE LEVELS

We consider a two-echelon inventory system with one warehouse and several stores. The warehouse as well as the stores are controlled by periodic review (s, S) inventory policies. We study the interrelationship between the safety stocks at the warehouse and the stores. Stockouts at the warehouse will result in supply delays to the stores and cause the lead time to be stochastic. The stores may react by increasing their safety stock. However, there is a trade-off between the safety stock at the warehouse and the safety stock at the stores. We use a service level at the warehouse to quantify the effect of warehouse stockouts on the lead time to the stores. The service level at the warehouse is considered a decision variable to find the best compromise between the various safety stocks by minimizing the overall costs. Using power approximations for the (s, S) policies, we provide an iterative procedure for adjusting the lead time distribution to the stores; this can result in substantial savings, but it doesn't guarantee the overall optimality. Numerical studies are provided to test the accuracy of approximations. The effects of the different system parameters on the inventory policy give general guidelines for use of the policies.     

PRESERVATION OF TRADE SECRETS AND MULTINATIONAL WAGE PREMIA

This paper considers the strategic behavior of a multinational firm with superior technology operating in a developing country. Domestic firms do not have access to the superior technology other than by hiring away multinational corporation (MNC) workers. The MNC can retain its workers by paying a wage premia, and we determine how the industry structure and the nature of strategic competition between firms affects the MNC's incentive to pay this premia and thus preserve its informational advantage. We characterize conditions under which MNCs inefficiently divide job tasks in order to raise the cost to domestic firms of acquiring the MNC's trade secrets. ( JEL F23, J31, O33)