Aerial multi-spectral AI-based detection system for unexploded ordnance

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...     

High-Velocity Projectile Impact Behaviour of Friction Stir Welded AA7075 Thick Plates

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...     

Burning rate analysis of laser controlled 5-aminotetrazole propellant

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...     

Microwave absorption properties of carbonyl iron-based paint coatings for military applications

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...     

使用低分辨率雷达和神经网络进行舰船目标识别

本文研究使用低分辩率下靶区雷达包络线、预处理和神经网络工具进行舰船目标分类的方法。文中使用改进的傅里叶离散梅林变换来提取对雷达姿态角变化不太敏感的某些特征。使用Kohonen的学习矢量量化(LVQ)自组织映射对这些特征矢量进行分类。文中也研究了使用反向传播算法进行训练的前馈网络在目标分类中的应用,并将这一分类系统用于模拟和真实两种数据。对于目标姿态角误差不超过30度的真实数据,分类的正确率高达90％。     

寻求新生的墨西哥海军

墨西哥位于北美洲南部,濒临太平洋和墨西哥湾,领土面积约190万平方公里,海岸线长达9300公里。墨西哥本应成为该地区重要的军事强国,但是它依赖美国抵御外来侵略,自己的武装部队仅充当维护内部安全的角色。无论从人员上还是从可用舰船数量上来讲,墨西哥海军一直与此不相称。墨西哥海军实质上只是一支海岸警备队,军事潜力非常有限。舰队虽然也拥有少数新式舰艇,但多数舰艇均是在20世纪40年代末期甚至更早服役的。整个舰队就像是20世纪海军技术博物馆。     

未来的作战指挥：信息技术、作战条件和编制体制的融合

先进的信息技术可大大增加各级部队所能运用的知识量,提高部队运用知识的能力。信息技术加上适宜的作战条令和编制体制,能极大地提高部队的战斗力。美国陆军应该迅速学会使用这些新工具,然后推广到全军。     

夺取海底控制权

上世纪30年代,德国在进行代号为“流星”的一次海洋考察中,首次使用回声探测器来探测海洋的深度。在此之前人们使用的深海探测装置是一种一颗炮弹与钢丝线相连接的,常用于浅水探测的装置。在浅水探测中,当炮弹与地底相碰撞时,操作员往往可以看见钢丝线突然变松。然而,在深海,钢丝     

小时候父亲这样教我

当我还坐在婴儿椅上的时候,父亲有一天带回家一堆小瓷片,就是那种装修浴室用的各种颜色的玩艺儿。我父亲把它叠垒起来,弄成像多米诺骨牌似的,然后我推动一边,它们就全倒了。过一会儿,我又帮着把小瓷片重新堆起来。 这次父亲让我变出些复杂点儿的花样：两白一蓝,两白一蓝 ......我母亲忍不住说：“唉,你让小家伙随便玩不就是了？他爱在哪儿加个蓝,就让他加好了。” 可我父亲回答道,“这不行,我正教他什么是序列,并告诉他这是多么有趣呢！这是数学的第一步。”我家有一套《大英百科全书》,父亲常让我坐在他的膝上,给我读里边的…