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201.
Unexploded ordnance(UXO) poses a threat to soldiers operating in mission areas, but current UXO detection systems do not necessarily provide the required safety and efficiency to protect soldiers from this hazard. Recent technological advancements in artificial intelligence(AI) and small unmanned aerial systems(sUAS) present an opportunity to explore a novel concept for UXO detection. The new UXO detection system proposed in this study takes advantage of employing an AI-trained multi-spectral(MS... 相似文献
202.
In this study, high velocity impact behaviour of friction stir welded AA7075-T651 25 mm thick plates were investigated using a 7.62 mm × 51 mm lead core and 7.62 mm × 39 mm steel core projectiles. Prior to ballistic trails, mechanical and metallurgical properties of friction stir welded AA 7075-T651 25 mm thick plates were studied. Microstructural and hardness studies revealed that friction stir welds constituted three distinct regions namely Weld Nugget(WN), Thermo-Mechanically Affected Zone(TM... 相似文献
203.
As an innovative propulsion technique, laser augmented chemical propulsion(LACP) seems superior to the traditional ones. However, the corresponding combustion theories have still to be ascertained for LACP. Burning rate of 5-aminotetrazole(5-ATZ) propellant has been studied by testing pressed samples under different combustor pressures and laser powers. Based on micro computed tomography(Micro CT),an advanced thickness-over-time(TOT) method to characterize the regression of the produced nonplana... 相似文献
204.
Wojciech Przyby? Adam Januszko Norbert Radek Marcin Szczepaniak Krzysztof A.Bogdanowicz Ireneusz Plebankiewicz Bogus?awa Szczodrowska Robert Mazurczuk 《防务技术》2023,(4):1-9
The paper explores the possibilities of using carbonyl iron in the form of a powder for the manufacture of radar-absorbing paints-reducing the radar signature of the objects that they cover. The attenuation values in the range of 4-18 GHz for various coating thicknesses, ranging from 0.5 to 2.00 mm with 0.5 mm increment, and for different absorber content-75% and 80%, as well as the use of two different binders in the form of epoxy resins with hardeners, were investigated. For the frequency of 1... 相似文献
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与主动战略防御相似,已经发展了反飞机和巡航导弹的国土防空概念,井称之为主动防空。主动防空最有希望的探测器之一就是天基雷达。作为大范围监视设备,工作在微波频段的天基雷达,对于象集群防御和战场监视这类任务范筹可能是很有用的。 相似文献