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对圆柱薄壳在四种不同运动模式激光源辐照下的温度场分布进行了分析研究。运用傅立叶级数展开法推导了在不同运动模式激光源作用下圆柱薄壳温度场的解析表达式,并对该解析表达式进行了编程计算,其计算结果与有限元解吻合良好。详细分析了旋转角速度与平动速度对圆柱壳温升分布的影响,发现在往复运动加热模式下光斑区域的温升变化最为剧烈。计算结果为导弹的抗激光辐射提供了理论依据。 相似文献
195.
Joanna R.Hall Olivia Matthews Timothy N.Volonakis Eric Liggins Karl P.Lymer Roland Baddeley Innes C.Cuthill Nicholas E.Scott-Samuel 《防务技术》2021,17(6):1833-1839
The human visual system is still an important factor in military warfare; military personnel receive training on effective search strategies, and camouflage that can effectively conceal objects and personnel is a key component of a successful integrated survivability strategy. Previous methods of camouflage assessment have, amongst others, used psychophysics to generate distinctiveness metrics. However, the population from which the human observers are drawn is often not well defined, or necessarily appropriate. In this experiment we designed a new platform for testing multiple patterns based on a camouflaged object detection task, and investigate whether trained military observers perform better than civilians. We use a two-alternative forced choice paradigm, with participants searching images of woodland for a replica military helmet displaying Olive Green, Multi Terrain Pattern, US Marine Pattern or, as a conspicuous control, UN Peacekeeper Blue. Our data show that there is no difference in detection performance between the two observer groups but that there are clear differences in the effectiveness of the different helmet colour patterns in a temperate woodland environment. We conclude that when tasks involve very short stimulus presentation times, task-specific training has little effect on the success of target detection and thus this paradigm is particularly suitable for robust estimates of camouflage efficacy. 相似文献
196.
Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED. 相似文献
197.
In order to examine the possibility to improve its camouflage properties standard cotton fabric with camouflage print was impregnated with poly(vinyl butyral), PVB and fullerene-like nanoparticles of tungsten disulfide, PVB/IF-WS2. FTIR analysis excluded any possible chemical interaction of IF-WS2 with PVB and the fabric. The camouflage behavior of the impregnated fabric has been examined firstly in the VIS part of the spectrum. Diffuse reflection, specular gloss and color coordinates were measured for three different shades (black, brown and dark green). Thermal imaging was applied to examine the camouflage abilities of this impregnation in IR part of the spectrum. The obtained results show that PVB/IF-WS2 impregnation system induced enhacement of the materials camouflage properties, i.e. that IF-WS2 have a positive effect on spectrophotometric characteristics of the fabric. 相似文献
199.
孙启华,1976年入伍.辽宁省彰武县人武部原部长。曾任雷锋生前所在团团长.现任铁岭军分区参谋长。2003年被评为“全军学雷锋先进个人”、沈阳军区学雷锋标兵。获“学雷锋金质荣誉章”,荣立二等功,并被辽宁省委、省政府评为学雷锋标兵,2004年,辽宁省军区党委作出向孙启华学习的决定。[编者按] 相似文献
200.
2005年11月15日至19日,法国海军“葡月”号轻型护卫舰(F734),在法国海军太平洋海区司令兼法国驻法属波利尼西亚部队司令帕德里克吉奥姆少将的率领下,对南海舰队进行了友好访问。来访当日,南海舰队在驻穗某军港码头举行了隆重的欢迎仪式。在驻广州某基地司令员余少英大校的陪同下,吉奥姆将军检阅了仪仗队,与前来迎接的舰队、基地及广州市有关单位领导握手,互致问候,并在码头接受了新闻媒体的采访。仪式结束后,吉奥姆将军一行拜会了南 相似文献