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341.
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
342.
QF炮膛擦拭剂的研制 总被引:1,自引:0,他引:1
介绍了QF炮膛擦拭剂的研制原理、配方、制备工艺、性能及应用情况。实验室理化性能测定和实际使用结果表明,该剂具有清洁能力强、防锈性好、使用方便等特点,对火炮射击结束后残留在炮膛内的火药残渣和尼龙残渣具有良好的去除作用,是一种应用前景广泛的武器装备维护保养新材料。 相似文献
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We study unreliable serial production lines with known failure probabilities for each operation. Such a production line consists of a series of stations, existing machines, and optional quality control stations (QCSs). Our aim is to decide on the allocation of the QCSs within the assembly line, so as to maximize the expected profit of the system. In such a problem, the designer has to determine the QCS configuration and the production rate simultaneously. The profit maximization problem is approximated assuming exponentially distributed processing times, Poisson arrival process of jobs into the system, and the existing of holding costs. The novel feature of our model is the incorporation of holding costs that significantly complicated the problem. Our approximation approach uses a branch and bound strategy that employs our fast dynamic programming algorithm for minimizing the expected operational costs for a given production rate as a subroutine. Extensive numerical experiments are conducted to demonstrate the efficiency of the branch and bound procedure for solving large scale instances of the problem and for obtaining some qualitative insights.
相似文献
344.
现代文本分类技术研究 总被引:1,自引:0,他引:1
周文霞 《中国人民武装警察部队学院学报》2007,23(12):93-96
分析了当前的文本分类技术,总结了文本分类需要解决的问题;在详细比较了各种不同的分类算法以及文本模型以后,为进一步开展优化以及提高文本分类技术的研究工作提供了一些参考和建议。 相似文献
345.
There are n boxes with box i having a quota value Balls arrive sequentially, with each ball having a binary vector attached to it, with the interpretation being that if Xi = 1 then that ball is eligible to be put in box i. A ball's vector is revealed when it arrives and the ball can be put in any alive box for which it is eligible, where a box is said to be alive if it has not yet met its quota. Assuming that the components of a vector are independent, we are interested in the policy that minimizes, either stochastically or in expectation, the number of balls that need arrive until all boxes have met their quotas. © 2014 Wiley Periodicals, Inc. 62:23–31, 2015 相似文献
346.
为了克服传统线性预测(Linear Prediction,LP)算法在构建虚拟阵过程中存在预测误差容易累积的弊端,提出了一种能够更充分利用实阵信息量的改进LP算法来构建虚拟阵。采用实际基阵方法、传统LP虚拟阵方法和改进LP虚拟阵方法分别对假定基阵的波束性能进行计算机仿真及对湖试数据进行处理成像,研究结果表明,与传统LP方法相比,改进的LP方法能够有效地抑制波束旁瓣,进一步提高了基阵的角度分辨力和阵增益,将其运用于特定试验背景下的实际湖底目标声探测,方向分辨精度可提高75%。 相似文献
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末端防御武器平台炮控系统性能的好坏直接影响首发命中率和射击反应时间等重要战技指标,在设计试验阶段,对其炮控性能进行检测是必不可少的环节。采用基于三棱锥模型的炮控性能检测方法,建立了三棱锥计算模型并进行Matlab仿真分析以及检测精度分析,从而验证了其工作原理及可行性,满足武器平台炮控性能检测的要求。 相似文献
350.
五电平有源中点钳位(five-level active-neutral-point-clamped, 5L-ANPC)变频器拓扑结构简单,可直接通过公共直流母线供电,易于实现能量回馈,非常适合用于5~10 kV直流供电的船舶推进变频调速领域。简要介绍了5L-ANPC的主电路拓扑和工作原理,针对5L-ANPC拓扑杂散参数较大的四种换流回路,在兼顾可靠性及适装性前提下,设计了纯电容吸收电路。在上述基础上,分析了设置吸收电路后的5L-ANPC拓扑采用传统电压过零切换策略时存在的内开关管过压问题,并提出一种考虑吸收电路的切换策略,实现了输出电压过零器件安全切换,且避免了电压异常跳变。通过仿真和实验验证了所提考虑吸收电路的输出电压过零切换策略的有效性、正确性。 相似文献