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81.
根据未来高技术战争和信息技术的发展趋势,提出了建设"E体化"军事物流的宏观战略构想,论述了"E体化"军事物流的理论内涵和现实意义,明确提出了"E体化"军事物流的战略目标以及目标实现的关键基础体系.  相似文献   
82.
EDITOR'S NOTE     
The Nonproliferation Review (NPR) recently interviewed Ambassador Sergio de Queiroz Duarte of Brazil, who presided over the 2005 Seventh Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Ambassador Duarte discussed his views on the outcome of the conference and the future of the treaty. He provided NPR with valuable insights into the outcome of the conference and also shared his thoughts on some of the most pressing issues confronting the NPT today, including the Middle East, nuclear terrorism, elimination of the threat of highly enriched uranium in the civilian nuclear sector, proposals to limit access to the nuclear fuel cycle, nuclear disarmament, and negative security assurances. Blaming the failed conference on a general lack of political commitment among states parties and their unwillingness to negotiate common solutions, Ambassador Duarte stressed that “the conference should face squarely its own failure without my attempting to disguise or sugarcoat the deep differences of view, which must be resolved with courage and determination by the states parties if they want the treaty to remain effective.”?He emphasized that if states fail to act on their overriding interest in upholding the NPT, especially if states parties continue to ignore or disregard their nonproliferation and nuclear disarmament obligations, some states might come to believe that their security interests are no longer served by the treaty. The future prospects of the NPT would then “look dire indeed.”  相似文献   
83.
为研究掺砂率对高庙子膨润土一砂混合型缓冲/回填材料液塑限的影响,利用液塑限联合测定仪进行了试验研究,并运用最小二乘法对混合物液塑限试验数据进行了分析。试验结果表明膨润土一砂混合物的可塑性、液塑限值和塑性指数均随掺砂率的增大而降低。对试验结果进行分析,得到了考虑掺砂率影响的混合物液塑限经验公式。混合物的液塑限并不是随掺砂率增大成比例降低,而是液限的实测值小于理论值,塑限的实测值大于理论值。得到的不同掺砂率的膨润土一砂混合型缓冲/回填材料液塑限试验数据可为高放废物深地质处置库建设提供科学依据。  相似文献   
84.
聚合物材料具有的易燃性或可燃性使其在实际应用中具有潜在的火灾危险性,正确分析评价聚合物材料的火灾危险性,对材料的安全使用和火灾预防与控制具有重要的作用。在综述文献的基础上,根据火灾危害的特征,对聚合物材料的引燃、热释放和火焰传播等热危险性进行了分析和总结,并提出了相应的预防对策。  相似文献   
85.
《防务技术》2020,16(5):1073-1087
Because of the uncertainty and subjectivity of decision makers in the complex decision-making environment, the evaluation information of alternatives given by decision makers is often fuzzy and uncertain. As a generalization of intuitionistic fuzzy set (IFSs) and Pythagoras fuzzy set (PFSs), q-rung orthopair fuzzy set (q-ROFS) is more suitable for expressing fuzzy and uncertain information. But, in actual multiple attribute decision making (MADM) problems, the weights of DMs and attributes are always completely unknown or partly known, to date, the maximizing deviation method is a good tool to deal with such issues. Thus, combine the q-ROFS and conventional maximizing deviation method, we will study the maximizing deviation method under q-ROFSs and q-RIVOFSs in this paper. Firstly, we briefly introduce the basic concept of q-rung orthopair fuzzy sets (q-ROFSs) and q-rung interval-valued orthopair fuzzy sets (q-RIVOFSs). Then, combine the maximizing deviation method with q-rung orthopair fuzzy information, we establish two new decision making models. On this basis, the proposed models are applied to MADM problems with q-rung orthopair fuzzy information. Compared with existing methods, the effectiveness and superiority of the new model are analyzed. This method can effectively solve the MADM problem whose decision information is represented by q-rung orthopair fuzzy numbers (q-ROFNs) and whose attributes are incomplete.  相似文献   
86.
建立了横观各向同性压电材料中的共线非等长多裂纹模型。将裂纹模拟为连续分布的广义位错,推导了单点广义位错的格林函数,并基于此得到了共线非等长多裂纹的奇异积分方程组,最后由数值计算给出了裂纹尖端的能量释放率。对奇异积分方程组的退化分析和对称条件下的数值结果的讨论,验证了本文结果的正确性。研究表明:当共线裂纹间距小于裂纹长度时,裂纹尖端场存在显著的干涉效应;裂纹越长,干涉效应越显著;电载荷系数越大,能量释放率也越大;相对于外侧尖端而言,共线裂纹内侧尖端对电载荷系数更为敏感。  相似文献   
87.
建立了压电界面电极的力学模型,利用有限傅里叶变换方法将相应的力电耦合问题描述为奇异积分方程,并得到了界面应力及其强度因子的解析解。讨论了结构几何参数对应力强度因子的影响。基于强度设计的观点得到两方面的结论:一是界面中心电极优于偏置电极;二是界面长度的最优值为中心电极长度的2倍。  相似文献   
88.
《防务技术》2020,16(4):893-899
Based on the elastic theory of cylindrical shells and the theory of composite laminates, a prediction model for the residual prestress of the simplified round composite barrel for railgun is established. Only the fibre pretension is considered in this model. A three dimensional numerical simulation for the residual prestress in the railgun barrel is carried out, by combining the temperature differential method with the element birth and death technology. The results obtained by the two methods are compared. It reveals that the distribution trends of residual prestress are consistent. And the difference for residual prestress in the filament wound composite housing of barrel is relatively small. The same finite element method is used to analysis the residual prestress in the non-simplified composite barrels for railgun, which are under different control modes of winding tension. The results mean that the residual prestress in barrel will increase while the taper coefficient for winding is decreasing. Therefore, the sealing performance in bore is improved, but the strength of the filament wound composite housing drops. In addition, the axial and circumferential residual prestress in the filament wound composite housing with constant torque winding are close to the ones in iso-stress design for barrel.  相似文献   
89.
B4C/Al复合板中应力波行为分析(Ⅰ)   总被引:1,自引:1,他引:0  
依据7.62mm穿甲燃烧弹与B4C,Al板的物理和力学特性,提出弹、板的力学模型;在此基础上,给出弹板碰撞后B4C/Al复合板的弹性动力学方程,建立应力波的传播模型,讨论了应力波传播时复合板的力学行为,最后确定了复合板承受的初始冲击应力。理论分析表明:一维应变条件的B4C和Al板的弹性极限高于一维应力条件下的值;弹、板间的作用力服从指数衰减规律;B4C板的初始应力高于430MPa时,应力波的作用使Al板在卸载过程中发生反向屈服。  相似文献   
90.
The claim that reactor-grade plutonium cannot or will not be used to produce nuclear weapons has been used to justify non-nuclear-weapon states’ large stockpiles of plutonium that has been separated from highly radioactive spent fuel. However, by using reduced-mass plutonium cores, it is possible to manufacture reliable nuclear weapons with reactor-grade plutonium. These weapons can have the same design, size, weight, and predetonation probability as weapons using weapon-grade plutonium and would require no special cooling. The increased radiation from reactor-grade plutonium could be easily managed by shielding and operational procedures. Weapons using plutonium routinely produced by pressurized-water reactors could have a lethal area between 40 percent and 75 percent that of weapons using weapon-grade plutonium. In the past, both Sweden and Pakistan considered using reactor-grade plutonium to produce nuclear weapons, and India may be using reactor-grade plutonium in its arsenal today. Despite claims to the contrary, the United States used what was truly reactor-grade plutonium in a successful nuclear test in 1962. The capability of reactor-grade plutonium to produce highly destructive nuclear weapons leads to the conclusion that the separation of plutonium, plutonium stockpiling, and the use of plutonium-based fuels must be phased out and banned.  相似文献   
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