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91.
直接序列扩频通信抗干扰性能分析 总被引:10,自引:0,他引:10
简述了直接序列扩频通信基本原理,讨论了直接序列扩频通信的特点,对直接序列扩频通信系统的抗干扰能力进行研究,最后提出了几种用于提高该通信系统抗干扰能力的具体方法。 相似文献
92.
抗日战争时期,中国远征军应邀入缅,在滇缅战场上英勇作战,配合盟军沉重抗击了日本侵略军,形成了有利的战略态势,为反法西斯战争的最后胜利奠定了坚实的基础,并作出了巨大的贡献。 相似文献
93.
基于遗传算法的观察所优化配置 总被引:1,自引:1,他引:0
文章研究了三维地形中的观察所优化配置问题,结合观察所实际情况,给出了利用遗传算法进行观察所优化的计算方法,并编制了计算机应用程序.计算机模拟实验表明,文中采用的算法能综合考虑多种因素,所得结果合理、准确,并且具有较高的效率. 相似文献
94.
金成 《武警工程学院学报》2011,(5):85-88
“慎战”是孙子军事思想中层次最高的战争决策思想,其理论主要包括不战思想、重战思想、善战思想和善后思想。在以和平与发展为主题的时代,孙子的“慎战”思想启示我们:要牢固树立“兵者,国之大事”的观念,加强部队现代化建设步伐,制定正确决策,“先为不可胜”;要以“非危不战”为原则,遏制犯罪,维护稳定,努力创造和平稳定的社会环境;要依据“胜于无形”,认真处理国内民族及其他矛盾,保持和谐稳定的社会环境。 相似文献
95.
This article considers batch scheduling with centralized and decentralized decisions. The context of our study is concurrent open shop scheduling where the jobs are to be processed on a set of independent dedicated machines, which process designated operations of the jobs in batches. The batching policy across the machines can be centralized or decentralized. We study such scheduling problems with the objectives of minimizing the maximum lateness, weighted number of tardy jobs, and total weighted completion time, when the job sequence is determined in advance. We present polynomial time dynamic programming algorithms for some cases of these problems and pseudo‐polynomial time algorithms for some problems that are NP‐hard in the ordinary sense. © 2010 Wiley Periodicals, Inc. Naval Research Logistics 58: 17–27, 2011 相似文献
96.
程建国 《军队政工理论研究》2011,12(3):3-5
深入贯彻主题主线重大战略思想,努力推动院校全面转型、特色发展,要以深入学习实践科学发展观为根本;要把提高教育质量作为核心;要把加强学科专业建设和教学模式创新作为主攻方向;要把加强人才队伍建设作为关键;要把加强思想作风建设作为重要保证. 相似文献
97.
98.
In order to understand the mechanism of conoidal fracture damage caused by a high-speed fragment-simulating projectile in titanium alloy layer of a composite armor plate composed of titanium- and aluminum-alloy layers, the ballistic interaction process was successfully simulated based on the Tuler-Butcher and GISSMO coupling failure model. The simulated conoidal fracture morphology was in good agreement with the three-dimensional industrial-computed-tomography image. Further, three main damage zones (zones I, II, and III) were identified besides the crater area, which are located respectively near the crater area, at the back of the target plate, and directly below the crater area. Under the high-speed-impact conditions, in zone II, cracks began to form at the end of the period of crack formation in zone I, but crack formation in zone III started before the end of crack formation in zone II. Further, the damage mechanism differed for different stress states. The microcracks in zone I were formed both by void connection and shear deformation. In the formation of zone I, the stress triaxiality ranged from-2.0 to-1.0, and the shear failure mechanism played a dominant role. The microcracks in zone II showed the combined features of shear deformation and void connection, and during the for-mation process, the stress triaxiality was between 0 and 0.5 with a mixed failure mode. Further, the microcracks in zone III showed obvious characteristics of void connection caused by local melting. During the zone III formation, the triaxiality was 1.0-1.9, and the ductile fracture mechanism was dominant, which also reflects the phenomenon of spallation. 相似文献
99.
Due to its high strength, high density, high hardness and good penetration capabilities, Depleted ura-nium alloys have already shined in armor-piercing projectiles. There should also be a lot of room for improvement in the application of fragment killing elements. Therefore, regarding the performance of the depleted uranium alloy to penetrate the target plate, further investigation is needed to analyze its advantages and disadvantages compared to tungsten alloy. To study the difference in penetration per-formance between depleted uranium alloy and tungsten alloy fragments,firstly, a theoretical analysis of the adiabatic shear sensitivity of DU and tungsten alloys was given from the perspective of material constitutive model. Then, taking the cylindrical fragment penetration target as the research object, the penetration process and velocity characteristics of the steel target plates penetrated by DU alloy frag-ment and tungsten alloy fragment were compared and analyzed, by using finite element software ANSYS/LS-DYNA and Lagrange algorithm. Lastly, the influence of different postures when impacting target and different fragment shapes on the penetration results is carried out in the research. The results show that in the penetration process of the DU and tungsten alloy fragments, the self-sharpening properties of the DU alloy can make the fragment head sharper and the penetrating ability enhance. Under the same conditions, the penetration capability of cylindrical fragment impacting target in vertical posture is better than that in horizontal posture, and the penetration capability of the spherical fragment is slightly better than that of cylindrical fragment. 相似文献
100.