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201.
如果美国能够控制亚丁湾和马六甲海峡,那么它将会在印度洋上的这场“宏大的博弈”中取得不可撼动的地位。美方想以控制上述所有战略要地向中方发出一个强烈的信息:如果认为美国在亚洲的影响力已大幅下降,那将是大错特错。 相似文献
202.
Recent progress in developing ballistic and anti-impact materials:Nanotechnology and main approaches
With increasing international and civilian conflicts, developing advanced body armor has become an emerging field in academia and industry. Nanotechnology, by means of, incorporating nanomaterials, is considered a highly effective technique to achieve this goal. It has been widely studied in defense applications owing to high strength-to-weight ratios and excellent energy absorption capability of nanomaterials. Hence, this review encompasses the latest application of nanotechnology involving nan... 相似文献
203.
The shielding and corrosion properties of the Alloy 709 advanced austenitic stainless steel have been investigated as a candidate canister material in spent fuel dry casks. The results revealed that the experimental and computational data of the linear and mass attenuation coefficients of the alloy are in good agreement, in which the attenuation coefficient values decreased with increasing photon energy.Alloy 709 was shown to exhibit the highest linear attenuation coefficient against gamma rays ... 相似文献
204.
Natural vibration of cantilever porous twisted plate with variable thickness in different directions
In this paper, the blade is assumed to be a rotating variable thickness cantilever twisted plate structure,and the natural vibrations of variable thickness cantilever twisted plate made of metal porous material are studied. It is assumed that the thickness of the plate changes along spanwise direction and chordwise direction, respectively, and it changes in both directions. The classical thin shell theory, the first and second fundamental forms of surface and von Karman geometric relationship ar... 相似文献
205.
This paper investigates the effects of the physical properties on the microstructure and weldability of explosive welding by joining two metals with a significant contrast in thermophysical properties:stainless steel and copper. Sound welds between stainless steel and copper were obtained, and the interfacial morphology was wavy, regardless of the position of the materials. The weldability of dissimilar pairs was found to be more dependent on the relationship between the physical properties of t... 相似文献
206.
Hongxu Wang Dakshitha Weerasinghe Paul J.Hazell Damith Mohotti Evgeny V.Morozov Juan P.Escobedo-Diaz 《防务技术》2023,(4):37-53
This study elaborates on the effects of matrix rigidity on the high-velocity impact behaviour of UHMWPE textile composites using experimental and numerical methods. Textile composite samples were manufactured of a plain-weave fabric(comprising Spectra? 1000 fibres) and four different matrix materials.High-velocity impact tests were conducted by launching a spherical steel projectile to strike on the prepared samples via a gas gun. The experimental results showed that the textile composites gradu... 相似文献
207.
The conventional case of patch repair involves bonding a patch over single damage/hole in the laminate.This work investigates the effect of interaction of two holes on the tensile behavior patch repaired carbon epoxy woven laminates. The specimens of [0°/45°/45°/0°] laminates were repaired with adhesively bonded two-ply [45°]2external patches. Three different cases of drilled specimens were produced with different hole arrangements viz. specimens with single central hole(SH), with two holes alig... 相似文献
208.
对海战场综合态势进行态势评估和威胁分析是信息融合系统的最高层级,态势评估结果将对指挥员的指挥决策起到非常重要的作用。根据海军作战理论分析了海战场态势的表示方法,并基于模板方法设计了一种战场当前态势与模板数据库中态势进行匹配的算法。该算法特别适用于高层推理如态势或威胁评估。 相似文献
210.
目前,美国实用的潜艇用电气和电子系统设计实际上是彼此独立的。这样的实践限制了利用过去几十年所获得的技术进步的优点。为了使潜艇平台的能力最大化,必须综合传统的、具有类似处理和通信要求的各个系统。本文研究和分析一种可能的称之为FIFT C~3I系统的实现,该系统综合支援潜艇任务的所有主要的电气和电子系统。这样的系统必须有容错能力,以致于使综合系统的可靠性、可用性和安全性等于或优于要替换的现有系统。这种方法的优点很多且可用现有技术和部件实现。 相似文献