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51.
This paper deals with an economic order quantity (EOQ) model for non-instantaneous deteriorating items with price and advertisement dependent demand pattern under the effect of inflation and time value of money over a finite planning horizon. In this model, shortages are allowed and partially backlogged. The backlogging rate is dependent on the waiting time for the next replenishment. This paper aids the retailer in minimising the total inventory cost by finding the optimal interval and the optimal order quantity. An algorithm is designed to find the optimum solution of the proposed model. Numerical examples are given to demonstrate the results. Also, the effect of changes in the different parameters on the optimal total cost is graphically presented and the implications are discussed in detail. 相似文献
52.
园林是时空的艺术;造园处处涉及虚实。实是指物境的建造,而虚则可指情弹与意境的开拓。化实为虚,虚实相生,由触景生情到情景交融,这正是中国园林艺术的魅力之所在。该文就中国园林的虚实之美进行了论述。 相似文献
53.
When an elastomeric material is deformed and subjected to temperatures above some characteristic value Tcr (near 100 °C for natural rubber), macromolecular chains and crosslinks undergo scission, recoiling and re-crosslinking. The process depends on time and temperature and continues until the temperature decreases below Tcr. Compared to the virgin material, the new material system has modified properties (reduced stiffness) and permanent set on removal of the applied load.A constitutive theory that accounts for these changes in macromolecular structure is used to simulate an experiment involving the inflation of an initially flat circular membrane. The membrane is initially at a temperature T < Tcr. A prescribed volume of fluid inflates the membrane to a surface of revolution. The temperature of the fluid and membrane is increased above Tcr for some period of time. Attention is restricted to the case when scission is independent of the deformation of the membrane. It is shown that the time dependence of the pressure in the inflating fluid must satisfy a specific relation involving a time dependent property measured during scission under uniaxial extension. This result provides a useful experimental means for determining when scission is independent of deformation in biaxial deformations.The temperature is returned to its original value and the pressure is gradually removed. It is shown that compressive stresses may develop as the pressure is reduced. If the membrane is removed from its support, it will have developed a permanently curved shape. Results of a numerical simulation are presented that compares the initial inflated shape to the permanently curved shape. 相似文献
54.
86 children ranging in age from 5 to 14 were asked "How old do you think Peter Pan was?", after seeing the Walt Disney cartoon film, Peter Pan. For the entire group, the Pearson r for their ages and the guessed age for Peter Pan was .51. "Sharing imaginatively in Peter's adventures, the child presumably feels close to Peter and therefore perceives Peter as resembling himself." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
This study examined 3- to 5-year-olds' (N = 128; 54% girls) ability to discriminate emotional fantasy and reality. Children viewed images depicting fantastic or real events that elicited several emotions, reported whether each event could occur, and rated their emotional reaction to the image. Children were also administered the Play Behavior Questionnaire and Pretend Action Tasks to assess play behaviors. Findings revealed age-related improvements in performance and biases in judgment based on the emotion depicted. Children reported that happy fantastic events could occur significantly more often than frightening and angry fantastic events and that happy real events could occur significantly more often than frightening and angry real events. Children's emotional reactions to the images but not play behaviors were significantly related to their fantasy-reality distinctions. Implications for the relation between emotions and children's fantasy-reality distinctions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
在传媒业发达的当今,动画片成为儿童认识世界的一个主要渠道,有选择地收看动画片是家庭教育的一部分。学龄前后是创造力这种复合能力培养的最佳时期。本文以一部经典作品为例,帮助家长从优化多元性格、培养观察力和想象力、保持好奇心、自主寻找答案等角度出发,甄选有益身心的动画片,让儿童在快乐中开启创造潜能。 相似文献
57.
在建筑院校建筑教育深刻变革的今天,苏州科技大学也进行着较为深入的教学改革和研究。本文提出了建筑设计基础教学中空间观培养的重要性,并以空间认知、空间想象和空间创造能力的培养为切入点,探讨了教学体系中相对应的调整和革新。 相似文献
58.
某矿开采9~#煤作为下保护层瓦斯治理研究 总被引:2,自引:2,他引:0
结合某矿生产实际,运用理论计算和数值模拟得出9#煤层上覆岩层的冒落带高度为12~18 m,裂隙带高度30~48 m,即3#煤层位于9#煤层产生的裂隙带的中上部,且处于9#煤层产生的卸压区范围内,3#煤层膨胀率在卸压范围内绝大部分超过3‰,并且3#煤卸压范围中部存在先膨胀后压缩的过程。最后利用膨胀率和工程类比对卸压效果进行了预测,综合分析认为保护层开采能有效卸压和增加煤体透气性,为3#煤层高效开采提供有利环境,从而论证了9#煤可以作为3#煤的保护层。 相似文献
59.
针对基于自发脑电信号的脑机接口研究,设计了一种科学的且易实现的运动想象实验范例,利用运动想象脑电作为BCI的控制信号.该实验方案能有效地获得可识别的、具有特征性的自发脑电,满足脑机接口实验要求,为BCI的研究提供了一种更加自然、更加实用的控制方式. 相似文献
60.
现场测量粘性细颗粒泥沙临界起动条件方法众多,便携式泥沙起动测量装置以其轻便快捷的优点越来越受到关注。利用成熟的商业流体计算软件FLUENT分别建立二维、三维数值模型,从模型维度、湍流模型、膨胀层网格3个方面对便携式泥沙起动测量装置的模拟效率与精度进行研究。结果表明,二维简化模型与三维模型的计算结果吻合较好,但二维模型的计算效率比三维模型高的多;RNGκ-ε、Realizableκ-ε湍流模型模拟所得底部床面产生的水流剪切力基本相同;膨胀层网格可在提高数值模型计算结果精度的同时减少模型总网格数量,提高模型计算效率。该结果可为泥沙起动装置设计和数值模拟研究提供参考。 相似文献