To explore whether swimming would increase the concentration of BE、NPY,and change the pain tolerance threshold...
Bo XU1,2,Feng YU2,Chenghui SONG3,Liu JI1,2 1 Key Laboratory of Adolescent Health Assessment and Exercise Intervention,Ministry of Education,Shanghai,China, 200241 2 College of Physical Education and Health,East China Normal University,Shanghai,China,200241 3 Department of Psychology,University of Wisconsin,P.O.Box 413,Milwaukee,WI 53201,USA
为了实现物流服务供应链中的集成服务提供商(Integrated Service Provider,ISP)和客户企业间的双赢互惠目标,本文采用Stackelberg博弈和最优化理论研究了商业信用和数量折扣组合合同下的物流服务供应链的协调策略。首先,构建单一商业信用下ISP和客户企业的决策模型,分析表明商业信用能够提高客户企业和系统的存货决策量,通过调整合同参数可以改善两者的利润,但是单一的商业信用不能实现物流服务供应链的完美协调。在此基础上,构建和分析了商业信用下ISP与客户企业的数量折扣模型,结果表明数量折扣率在一定范围内取值,商业信用和数量折扣组合合同可以激励客户企业进一步提高存货量,实现供应链系统的协调。最后通过数值算例证明所得结论的正确性。
Almost all experimental and theoretical studies on regenerative cryocoolers at temperatures below 20 K mention the use of 4He as working fluid.A preliminary qualitative evaluation indicates that because of the superfluid phase transition,a working fluid of 3 He would overcome the cooling temperature limitation set by 4He.Starting with a comparison of the thermophysical properties of 3He and 4He,cryogenic regenerator simulations applied to the third/last stage of a pulse tube refrigerator,with 3He and 4He separately,were implemented to quantitatively analyze performance differences of the regenerator with respect to regenerator loss, cooling power and COP.Results conclude that 3He could significantly improve the performance of a regenerative cryocooler.
