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71.
基于抗战初期华北敌后晋察冀军区的成立、边区的开辟及抗战形势的需要,中共中央作出筹建晋察冀边区政府的决策,这一决策始于聂荣臻1937年11月8日的建议;筹建边区政府的组织称谓,不是称"晋察冀边区军政民代表大会筹备处",而是称"晋察冀边区临时政府筹备处";晋察冀边区军政民代表大会的召开,不是1938年1月11日至15日,而是1938年1月10日至15日;与会代表人数,不是146人,也不是148人,而是各县代表145人,筹备委员4人,共149人;边区政府成立时的辖区范围,不是军区成立时的36个县,也不可能建立晋东北、冀西、冀中3个政治主任公署,而是从平汉路西扩展到了冀中平原,达40余个县;边区军政民代表大会选举产生了边区行政委员会,并制定了正确的施政方针和政策,这"两大建树"创造了高举抗日与民主的大旗与运用合法性策略开展工作完美结合的经验。 相似文献
72.
This article is concerned with a general multi‐class multi‐server priority queueing system with customer priority upgrades. The queueing system has various applications in inventory control, call centers operations, and health care management. Through a novel design of Lyapunov functions, and using matrix‐analytic methods, sufficient conditions for the queueing system to be stable or instable are obtained. Bounds on the queue length process are obtained by a sample path method, with the help of an auxiliary queueing system. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
73.
军事装备大数据是实现军事现代化、智能化的基础,其中,数据共享对实现装备可视化管理、整合装备供应链、优化指挥控制系统等具有至关重要的作用。军事装备数据涉及核心机密,数据的安全共享问题是导致这些技术发展迟缓的关键因素之一。区块链是一种具有去中心化、不可篡改、稳定可靠等特性的分布式链式账本技术,利用区块链技术和云计算可以保障装备数据安全,在军事领域有着广阔的发展前景。本文面向装备数据安全共享业务开展研究,探讨利用基于属性加密技术和智能合约技术解决不同主体间的信任问题,并提出了基于区块链的装备数据安全共享方案,以打破传统装备系统中的“信息孤岛”现象。 相似文献
74.
Hong-bin Xie Hui-ya Yang Jian Yu Ming-yu Gao Jian-dong Shou You-tong Fang Jia-bin Liu Hong-tao Wang 《防务技术》2021,17(2):429-439
Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and obscurity.It is found that the rail should withstand huge mechanical and thermal shocks during the launching operation.The forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,etc.The service life of the rail has become a bottleneck restricting the development of elec-tromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail materials.This paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and properties.We begin from a short background of the requirement of the rail material.Then a detailed investigation of rail materials is described,and the performances of those materials are introduced.Finally,further development prospect of rail material is discussed. 相似文献
75.
Shu-jie Liu Bi-dong Wu Jia-ni Xie Zhi-min Li Chong-wei An Jing-yu Wang Xiao-dong Li 《防务技术》2021,17(5):1775-1781
Insensitive energetic materials are promising in the defense weapons field. However, energetic materials still suffer from great challenges and the concern about their safety limits their utilization. In this work, insensitive energetic explosive 3,3′-diamino-4,4′-azoxyfurazan/hexahydro-1,3,5-trinitro-1,3,5-triazine (DAAF/RDX) microspheres were fabricated by self-assembly method. Rod-like DAAF/RDX was prepared by mechanical ball milling for comparison. DAAF/RDX composites with different mass ratios (90:10, 80:20, and 70:30) were obtained. The morphologies and structures of as-obtained DAAF/RDX composites were characterized by scanning electron microscopy (SEM), powder x-ray diffraction (PXRD) and fourier transform infrared spectroscopy (FT-IR). The results showed that DAAF/RDX microspheres exhibited regular shaped microspheres with sizes from 0.5 to 1.2 μm. There was no crystal transition during the modification process. The thermal properties of as-obtained materials were then evaluated by differential scanning calorimetry (DSC) and materials studio software. DAAF/RDX microspheres showed an advanced decomposition peak temperature compared with rod-like DAAF/RDX. The binding energy and peak temperature values at zero βi (TP0) of DAAF/RDX (90:10) increased by 36.77 kJ/mol, 1.6 °C, and 58.11 kJ/mol, 12.3 °C compared to DAAF/RDX (80:20) and DAAF/RDX (70:30), indicating the better thermal stability of DAAF/RDX (90:10). The characteristic drop height (H50) of DAAF/RDX (higher than 100 cm) composites was higher than that of raw RDX (25 cm), suggesting significant improvements in mechanical safety. The preparation of DAAF/RDX microspheres is promising for the desensitization of RDX and useful for the formation of other materials and future wide applications. 相似文献
76.
We study joint preventive maintenance (PM) and production policies for an unreliable production‐inventory system in which maintenance/repair times are non‐negligible and stochastic. A joint policy decides (a) whether or not to perform PM and (b) if PM is not performed, then how much to produce. We consider a discrete‐time system, formulating the problem as a Markov decision process (MDP) model. The focus of the work is on the structural properties of optimal joint policies, given the system state comprised of the system's age and the inventory level. Although our analysis indicates that the structure of optimal joint policies is very complex in general, we are able to characterize several properties regarding PM and production, including optimal production/maintenance actions under backlogging and high inventory levels, and conditions under which the PM portion of the joint policy has a control‐limit structure. In further special cases, such as when PM set‐up costs are negligible compared to PM times, we are able to establish some additional structural properties. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
77.
电子战仿真数字系统模型及设计方法 总被引:3,自引:0,他引:3
阐述了在EW 系统建模、仿真和评估中采用电子战数字系统模型(EWDSM)的意义。结合电子战系统仿真评估的特点,讨论了EWDSM 在设计时采用的方法,如面向对象的分析方法的类层次和类结构,以及基于HLA/RTI的分布仿真协议的分布式计算环境的仿真系统设计。 相似文献
78.
本文在讨论单兵系统战场信息分类与信息库系统结构的基础上,提出了单兵战场信息库系统的功能与设计原则。然后,对单兵战场信息库系统中的信息处理流程进行了分析。 相似文献
79.
首先简要分析了单兵数字化系统中人机界面的设计原则,并根据单兵系统及其所处环境的特点,讨论了多种界面类型在该系统中的利弊、作用及实现的可能性。最后讨论了界面中各种信息的分组以及界面的展现(屏幕)设计 相似文献
80.
在诸如液体火箭发动机等复杂动力学系统的故障诊断中,监控参数组的优选问题一直受到工程技术人员的高度重视。本文提出了综合样本矢量方向离散度概念,以此作为故障特征参数的优选准则;然后利用经过改进的遗传算法,对某液体火箭发动机常见故障的诊断进行了特征参数组的优选。在改进的遗传算法中,采用了非常简洁而高效的染色体编码,针对特征优选的组合优化类问题专门设计了一种特殊的基因迁移算子,并引进了父本个体适应值的动态调整技术与共享函数。数值实验结果表明,该算法具有理想的效果。 相似文献