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391.
Sheng Kong Dong-jie Liao Yu-meng Jia Chong-wei An Chun-yan Li Bao-yun Ye Bi-dong Wu Jing-yu Wang Hao Guo Zhi-wei Hong 《防务技术》2022,18(1):140-147
A new type of explosive ink formulation that can be quickly cured was prepared with unsaturated polyester as binder,styrene as active monomer,2,4,6-trimethylbenzoyl-diphenylphosphine oxide as photoinitiator,and hexanitrohexaazaisowurtzitane (CL-20) as the main explosive.Then the explosive ink direct writing technology was used to charge the micro-sized energetic devices,the curing mechanism of the explosive ink was discussed,and the microstructure,safety performance and explosive transfer performance of the explosive ink molded samples were tested and analyzed.Results indicate that the composite material has a fast curing molding speed,its hardness can reach 2H within 8 min.The crystal form of CL-20 in the molded sample is still ε type.The CL-20 based W-curing explosive ink formulation has good compatibility,its apparent activation energy is increased by about 3.5 kJ/mol.The composite presents a significant reduction in impact sensitivity and its characteristic drop height can reach 39.8 cm,which is about 3 times higher than the raw material.When the line width of charge is 1.0 mm,the critical thickness of the explosion can reach 0.015 mm,and the explosion velocity is 7129 m/s when the charge density is 1.612 g/cm3. 相似文献
392.
《装甲兵工程学院学报》1995,(3)
对威布尔过程应用中的若干问题作了进一步探讨:如威布尔过程与威布尔分布;具有切断的故障数据处理;威布尔过程的拟合优度检验;可修系统可靠性评估参数;多个同型系统参数一致性检验等. 相似文献
393.
Most modern processes involve multiple quality characteristics that are all measured on attribute levels, and their overall quality is determined by these characteristics simultaneously. The characteristic factors usually correlate with each other, making multivariate categorical control techniques a must. We study Phase I analysis of multivariate categorical processes (MCPs) to identify the presence of change‐points in the reference dataset. A directional change‐point detection method based on log‐linear models is proposed. The method exploits directional shift information and integrates MCPs into the unified framework of multivariate binomial and multivariate multinomial distributions. A diagnostic scheme for identifying the change‐point location and the shift direction is also suggested. Numerical simulations are conducted to demonstrate the detection effectiveness and the diagnostic accuracy.© 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
394.
针对在异构网络环境下无线网络的特点使TCP性能下降的问题,借鉴TCP Veno算法原理,提出基于网络状况评估的拥塞控制的性能增强代理改进工作机制,动态评估当前网络的状况,调整预应答发送窗口的阈值,提高性能增强代理在较大差异网络下的传输控制效能.基于NS-2的网络仿真测试对算法进行了验证,结果显示改进后的工作机制在丢包率较大的异构网络中性能有明显提升. 相似文献
395.
提出了一种计算涡轮增压柴油机高原性能的方法.这种方法不涉及复杂的数值模拟计算,可以在较宽广的环境压力和环境温度范围预测涡轮增压柴油机的性能,具有较高的计算精度.对两台车用涡轮增压柴油机进行了实例计算,并与试验结果进行了对比.分析了海拔高度变化和温度变化引起的涡轮增压器和发动机性能的变化趋势. 相似文献
396.
A new piece of equipment has been purchased in a lot of size m. Some of the items can be used in destructive testing before the item is put into use. Testing uncovers faults which can be removed from the remaining pieces of equipment in the lot. If t < m pieces of equipment are tested, then those that remain, m1 = m − t, have reduced fault incidence and are more reliable than initially, but m1 may be too small to be useful, or than is desirable. In this paper models are studied to address this question: given the lot size m, how to optimize by choice of t the effectiveness of the pieces of equipment remaining after the test. The models used are simplistic and illustrative; they can be straightforwardly improved. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 623–637, 1997 相似文献
397.
398.
超音速环形引射器空气引射启动特性试验 总被引:3,自引:1,他引:3
建立了超音速环形引射系统,对环形引射器空气引射启动特性进行了试验研究.试验结果表明:管道马赫数越大,则系统启动压强越高,同时盲腔真空度越高;混合室收缩比越小,系统启动压强越低;若管道马赫数较大,而第二喉部长径比和亚音速扩压段面积比过小,引射器启动过程可能不稳定,甚至无法启动;混合室收缩比、环型引射器扩压管道参数对盲腔压强无影响. 相似文献
399.
负载平衡是并行处理中的一个重要概念。参与一个程序执行的各处理机所承担的工作量是否均衡直接影响该程序的并行性能。本文对面向MPP系统程序循环级并行化中负载平衡的优化进行了探讨,提出了优化策略及其实施算法。 相似文献
400.
并行离散事件仿真(Parallel Discrete Event Simulation,PDES)模型的正确性和可信度对PDES应用的发展起着决定性作用.然而,现有的并行离散事件仿真开发环境都没有提供仿真模型检验功能.并行模型检验(Parallel Model Checking,PMC)方法以其完备性、高效性已经在工业... 相似文献