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61.
介绍仿真机和仿真软件的发展,分析了银河仿真机系统性能,探讨了仿真机的未来发展特征。 相似文献
62.
办有特色期刊 走精品化道路——学报建设发展20年巡礼 总被引:2,自引:0,他引:2
对学报创刊 20年初创调整、改革进取和锻造品牌特色三个阶段进行了回顾;论述了学报在学院教学科研及部队建设中的地位和作用;总结分析了 20年的办刊经验,并从中得到了一些启示。 相似文献
63.
We consider a make‐to‐order production–distribution system with one supplier and one or more customers. A set of orders with due dates needs to be processed by the supplier and delivered to the customers upon completion. The supplier can process one order at a time without preemption. Each customer is at a distinct location and only orders from the same customer can be batched together for delivery. Each delivery shipment has a capacity limit and incurs a distribution cost. The problem is to find a joint schedule of order processing at the supplier and order delivery from the supplier to the customers that optimizes an objective function involving the maximum delivery tardiness and the total distribution cost. We first study the solvability of various cases of the problem by either providing an efficient algorithm or proving the intractability of the problem. We then develop a fast heuristic for the general problem. We show that the heuristic is asymptotically optimal as the number of orders goes to infinity. We also evaluate the performance of the heuristic computationally by using lower bounds obtained by a column generation approach. Our results indicate that the heuristic is capable of generating near optimal solutions quickly. Finally, we study the value of production–distribution integration by comparing our integrated approach with two sequential approaches where scheduling decisions for order processing are made first, followed by order delivery decisions, with no or only partial integration of the two decisions. We show that in many cases, the integrated approach performs significantly better than the sequential approaches. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005 相似文献
64.
本文在CADKEY绘图软件包的支持下,开发了加筋圆柱结构CAD系统—Hcadx.此系统通过菜单引导用户的操作,可用经验公式或解析法作轴压稳定分析,用罚函数法优化参数,可以在不退出Hcadx的情况下启动CADKEY,自动绘制设计草图。此草图经过适当地编辑、修改、便可成为工程中能接受的工作图纸。 相似文献
65.
Jian-hao Dou Xin Jia Zheng-xiang Huang Xiao-hui Gu Ying-min Zheng Bin Ma Qiang-qiang Xiao 《防务技术》2021,17(3):846-858
The use of a shaped liner driven by electromagnetic force is a new means of forming jets. To study the mechanism of jet formation driven by electromagnetic force, we considered the current skin effect and the characteristics of electromagnetic loading and established a coupling model of"Electric—Magnetic—Force"and the theoretical model of jet formation under electromagnetic force. The jet formation and penetration of conical and trumpet liners have been calculated. Then, a numerical simulation of liner collapse under electromagnetic force, jet generation, and the stretching motion were performed using an ANSYS multiphysics processor. The calculated jet velocity, jet shape, and depth of penetration were consistent with the experimental results, with a relative error of less than 10%. In addition, we calculated the jet formation of different curvature trumpet liners driven by the same loading condition and ob-tained the influence rule of the curvature of the liner on jet formation. Results show that the theoretical model and the ANSYS multiphysics numerical method can effectively calculate the jet formation of liners driven by electromagnetic force, and in a certain range, the greater the curvature of the liner is, the greater the jet velocity is. 相似文献
66.
Bin Ma Zheng-xiang Huang Zhong-wei Guan Xin Jia Xu-dong Zu Qiang-qiang Xiao 《防务技术》2021,17(5):1722-1730
The influence of a magnetic field on the stability of a shaped charge jet is experimentally investigated at standoffs of 490, 650 and 800 mm. The experimental results without and with the magnetic field are compared in terms of the shaped charge jet form, stability and penetration ability. A theoretical model based on one-dimension fluid dynamics is then developed to assess the depth of penetration of the shaped charge at those three standoffs and magnetic conditions. The results show that the penetration capability can be enhanced in more than 70% by the magnetic field. The theoretical calculations are compared with the experimental results with reasonably good correlation. In addition, the parameters introduced in the theory are discussed together with the experiments at three standoffs studied. 相似文献
67.
This paper sets up a monetary endogenous growth model, and uses it to explain the ambiguous linkage between the military burden and the inflation rate observed in existing empirical studies. It is found that an expansion in the military burden has an ambiguous effect on the inflation rate depending upon the relative extent of two conflicting forces. More specifically, if the increase in the marginal benefit from holding money exceeds (falls short of) the increase in the marginal product of private capital, the inflation rate will rise (fall) in response. Moreover, it is found that an increase in the military burden will stimulate the balanced growth rate, confirming Benoit’s famous empirical findings. 相似文献
68.
69.
在UMT-3摩擦磨损试验机上,将Si3N4、CCr15分别与巴氏合金进行了摩擦磨损试验,并利用扫描电镜和X射线能谱仪观察巴氏合金的磨损表面,探讨其磨损机理,为Si3N4-巴氏合金新型陶瓷轴承的实际应用提供理论依据.结果表明:载荷相同时,Si3N4-巴氏合金的平均摩擦因数和磨损率比CCr15-巴氏合金低;随着载荷的增加,Si3N4-巴氏合金的摩擦因数先升后降,波动幅度明显小于CCr15-巴氏合金;载荷为10N时,Si3N4-巴氏合金摩擦因数达到最大值0.13,在15N时达到最小值0.04;摩擦副整体磨损率较低,巴氏合金的磨损率随载荷增大而增大,平均为10-6 mm3/(N-m).在Si3N4-巴氏合金摩擦表面同时存在陶瓷氧化物润滑膜和金属磨屑,共同起到了润滑减摩的作用.Si3N4-巴氏合金作为陶瓷轴承的配合材料,具有比传统轴承更好的摩擦磨损性能,具有广阔的应用前景. 相似文献
70.