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《防务技术》2022,18(12):2160-2169
Most finite element models of small arms focus on an idealized barrel, typically one with a perfectly straight bore centerline. Using five different experimentally measured bore centerlines, this investigation analyzes the effect centerline nonlinearity has on projectile exit conditions. This includes the effect of rotating a centerline through several orientations. Modeled using Abaqus/Explicit, this dynamic analysis simulates a single firing cycle for each centerline. Projectile jump is calculated for each model as a measure of the effects of warped centerlines. The warped centerlines have a small effect on barrel dynamics. 相似文献
73.
总结论述了美国和英法国家的飞机电磁弹系统工程化应用研制的发展状况,综述了电磁弹射用直线电机的方案选型设计、仿真技术、性能优化和控制方法等方面的关键技术和研究现状,针对电磁弹射技术的发展前景和应用给出了相关建议,为国内电磁弹射相关技术的发展提供了借鉴。 相似文献
74.
为研究不同初始荷载作用下侧贴碳纤维布及侧贴预应力碳纤维布加固钢筋混凝土连续梁的加固效果,采用有限元分析软件ABAQUS对其进行数值模拟,并将有限元分析结果与试验结果对比。有限元分析表明:钢筋混凝土连续梁的加固效果受初始荷载的影响,初始荷载越小,加固效果越好;对纵向侧贴碳纤维布施加预应力,能够大幅提高钢筋混凝土连续梁的抗弯承载力,与未加固梁相比其抗弯承载力提高了65%以上;有限元计算结果与试验结果的荷载-挠度曲线吻合较好,两者的抗弯承载力相差不超过10%。所得结果可以为类似加固设计和试验提供参考。 相似文献
75.
Nuclear weapon states historically have attached great secrecy to their nuclear weapon and fissile material production programs and stockpiles, despite warnings that this would fuel fears, handicap informed debate and decision making, and drive arms races. As evidenced by the “Action Plan on Nuclear Disarmament” agreed upon at the 2010 Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Review Conference, however, the international community now sees greater transparency about nuclear weapon and fissile material stocks as necessary for enabling and monitoring progress toward nuclear disarmament. To support this effort, the International Panel on Fissile Materials has proposed a step-by-step program for weapon states to declare their inventories, production histories, and disposition of nuclear warheads and fissile materials, and to set up joint projects to develop methods for verifying these declarations. This openness initiative is described here, and could be adopted at the 2015 NPT Review Conference, laying a basis for negotiating verifiable deep reductions in nuclear arsenals and their eventual elimination. 相似文献
76.
Many countries received Soviet-origin highly enriched uranium (HEU) for civilian nuclear research purposes. Because of inadequate nuclear security at a number of the research sites, U.S. policy has sought to remove or otherwise safely dispose of their HEU stocks as quickly as possible. Although the pace of HEU disposition has accelerated significantly in recent years, several sites have posed formidable technical, economic, and political challenges. This article identifies the major obstacles to HEU removal at two key installations—Kharkiv in Ukraine, and Sosny in Belarus—and recommends a strategy for overcoming these impediments. Key components for a successful disposition strategy include: treating these cases with the urgency they deserve, expanding potential compensation packages, explicitly addressing the institutional and political issues involved, engaging high-level political leaders, working with third parties, and promoting these efforts as part of a nondiscriminatory initiative to phase out HEU in the civilian nuclear sector globally. 相似文献
77.
Egle Murauskaite 《The Nonproliferation Review》2013,20(3-4):321-339
ABSTRACTThis article explores the paradox of trust in the largest nuclear smuggling operation involving highly enriched uranium (HEU) discussed in open source literature. In the first effort to understand the type, extent, and role of trust in nuclear smuggling enterprises, it draws from literature on trust development in legitimate businesses as well as criminal enterprises. Observed behavioral patterns in this case challenge traditional notions of the internal dynamics of temporary groups engaged in nuclear smuggling and operational realities of such activities. The article seeks to explain why individuals agree (and continue) to operate in this high-risk environment, unbound by close personal ties, without any effort to verify the background, motives, or qualifications of the fellow conspirators. It offers ways to advance current nonproliferation efforts in non-state actor interdiction by exploiting the environment of shallow trust in temporary groups. 相似文献
78.
ABSTRACTThe 1993 Highly Enriched Uranium (HEU) Purchase Agreement between the United States and Russian Federation is often described as one of the world's most successful nuclear nonproliferation programs. In 2013, the two states achieved the agreement's major goals of downblending 500 metric tons of Russian weapon-origin HEU to low enriched uranium (LEU) and delivering all resultant LEU to the United States. At one time, the LEU delivered under the agreement generated nearly 10 percent of all electricity in the United States. The agreement achieved its nonproliferation goals through a unique government/industry partnership. Commercial executive agents contracted for the annual sale and delivery of downblended LEU, while the US and Russian governments exercised reciprocal transparency monitoring measures to demonstrate that all LEU delivered under the agreement was derived from Russian weapons-origin HEU, and that the same LEU was used for exclusively peaceful purposes in the United States. The commercial development, negotiations, and implementation of the agreement have been well documented. This article describes the scope of US transparency monitoring activities in Russian HEU processing facilities, as well as Russian monitoring in the United States. In addition, it discusses the results of twenty years of reciprocal transparency monitoring and data analysis, and outlines lessons learned that are potentially applicable to future transparency monitoring and verification regimes and similar cooperative efforts. 相似文献
79.
80.
本文采用二维电磁场有限元法及磁路的简化计算法对15cm×15cm磁悬挂天平系统(MSBS)的阻力线圈间距、磁场的分布情况进行了分析计算,并与测试结果进行了分析比较,给出了15cm×15cm磁悬挂天平系统(MSBS)的结构方案。 相似文献