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91.
In 1995, Padmanabhan and Vrat presented inventory models for deteriorating items with a constant selling price and stock dependent selling rate . Based on the result, in 2000, Kun-Jen Chung, Peter Chu and Shaw-Ping Lan devoloped the necessary and sufficient conditions of the existence and uniqueness of the optimal solutions of the profit per unit time functions without backlogging and with complete backlogging. Actually, the selling price need not be constant, it may be variable . This paper puts forward an EOQ model when the selling price is variable without backlogging, discusses the existence and uniqueness of optimum solution. The example is provided to illustrate the model. The theoretical evidence is provided for the inventory system to make management decision. 相似文献
92.
For certain types of inventory, the ordering cycle and demand may be random variants, which satisfy certain types distribution. The classical EOQ model usually neglects the fact. Based on the constant demand, under the hypothesis that the ordering cycle is a random variant which satisfies exponent distribution, average demand is a linear increasing function, this paper considers the effects of the time-value of capital and inflation on replenishment strategy of inventory system. Loosening the condition of basic economic order quantity model under deterministic state, the total cost function of the model is provided. The optimum order quantity and cycle are obtained. The application range of EOQ model under the constant demand is widened. The theoretical evidence is provided for the inventory system to make management decision. 相似文献
93.
It is important for enterprises' inventory management to find out the optimal production cycle and the length of shortage time,so that the total cost of inventory system can be reduced and the service level can be raised.Based on the classical EPQ model,this paper develops an EPQ model for deterioration items with different lost sale factor relative to the inventory level during shortage period.The existence of unique optimal solution is discussed by mathematic analysis and a numeric example.The sensitivity analysis shows that the parameter of losing sale has different impact on the costs of inventory system.The factors must be considered for the production inventory system to make management decision. 相似文献
94.
Aiming at the free-riding problem in team incentive, this paper designs a dynamic incentive mechanism based on implicit side contract with dynamic game theory by introducing the reasonable assumption that there is horizontal monitor in team production. The theoretic analysis indicates that the dynamic incentive mechanism, in which a strict group incentive compatibility contract is taken at the first stage and an individual incentive compatibility contract is taken at the second stage, can implement team cooperation uniquely in the general condition of risk aversion and stochastic production by only two stage repeated game. 相似文献
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叙述了有限元技术在疲劳寿命预测中的应用和一般的分析过程;着重介绍了疲劳载荷历程的合成规则和表面节点应力状态的判断方法;归纳评述了常用的多轴疲劳损伤模型;针对结构中普遍存在的焊缝焊点给出了具体的疲劳寿命分析方法;最后给出驱动桥壳疲劳寿命分析实例,计算结果和试验数据基本一致,说明基于有限元法的疲劳寿命预测是切实可行的,可以降低成本,缩短研发周期。 相似文献
99.
为提高天然气发动机的燃烧品质,基于6105型涡轮增压CNG发动机,通过建模分析法,对发动机不同燃烧室形状对缸内气流运动和燃烧特性的影响进行了三维数值模拟研究。研究结果表明,燃烧室形状对挤流的形成和燃烧过程有着重要影响。缩口型燃烧室具有较大的挤流强度和较长的涡流持续期,火焰传播速度快,燃烧性能好,但其火花塞附近的热负荷较大,NOx的含量高。敞口型燃烧室挤流强度较弱,火焰传播速度较慢,燃烧性能最差。直口型燃烧室则介于两者之间,既能保证较快的火焰传播速度和较好的燃烧性能,又降低了其火花塞附近的热负荷和NOx的排放量,是较适合天然气发动机采用的燃烧室。 相似文献
100.