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771.
以保证潜艇隐蔽性为前提,如何增强潜艇的战场态势感知能力是提升潜艇作战效能的关键。因此,以分析潜艇战场态势感知能力现状为基础,构建一种以无人平台作为战场单元,支持潜艇战场态势感知的连通性网络模型,并对其组成、功能及工作过程进行了详细设计;对战场单元的任务载荷和任务规划进行了详细阐述;最后从作战角度出发,展开连通性网络的作战应用研究。 相似文献
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An effective hybrid optimization method is proposed by integrating an adaptive Kriging (A-Kriging) into an improved partial swarm optimization algorithm (IPSO) to give a so-called A-Kriging-IPSO for maxi-mizing the buckling load of laminated composite plates (LCPs) under uniaxial and biaxial compressions. In this method, a novel iterative adaptive Kriging model, which is structured using two training sample sets as active and adaptive points, is utilized to directly predict the buckling load of the LCPs and to improve the efficiency of the optimization process. The active points are selected from the initial data set while the adaptive points are generated using the radial random-based convex samples. The cell-based smoothed discrete shear gap method (CS-DSG3) is employed to analyze the buckling behavior of the LCPs to provide the response of adaptive and input data sets. The buckling load of the LCPs is maximized by utilizing the IPSO algorithm. To demonstrate the efficiency and accuracy of the proposed methodology, the LCPs with different layers (2, 3, 4, and 10 layers), boundary conditions, aspect ratios and load patterns (biaxial and uniaxial loads) are investigated. The results obtained by proposed method are in good agreement with the literature results, but with less computational burden. By applying adaptive radial Kriging model, the accurate optimal results-based predictions of the buckling load are obtained for the studied LCPs. 相似文献
774.
Presented herein is an experimental study on the combustion of B4C/KNO3 binary pyrotechnic system.Combustion products were tested using X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometer(EDS).According to the results of tests and CEA calculation,the combustion reaction equation was established.The flames and burning rates were recorded by a high speed camera and a spectrophotometer.The effect of B4C particle size on the thermal sensitivity of B4C/KNO3 was investigated by differential scanning calorimetry(DSC)techniques.In addition,a reliable method for calculating the flame temperature was proposed.Based on the results of experiments,the combustion reaction mechanism was briefly analyzed.The burning rate,flame temperature and thermal sensitivity of B4C/KNC3 increase with the decrease of B4C particle size.The mass ratio of B4C/KNO3 has a great effect on combustion properties.Oxidizer-rich compositions have low flame temperatures,low burning rates,and provide green light emission.The combustion reactions of fuel-rich compositions are vigorous,and the B4C/KNO3 with mass ratio of 25:75 has the highest burning rate and the highest flame temperature. 相似文献
775.
In this work, NH2-substituted oxazoles and NO2/NF2/NHNO2-substituted ethylenes/acetylenes were designed and used as dienes and dienophiles, respectively, in order to develop new bridge-ring insensitive high energy compounds through the Diels-Alder reaction between them. The reaction type, reaction feasibility and performance of reaction products were investigated in detail theoretically. The results showed that dienes most possibly react with dienophiles through the HOMO-diene controlled normal Diels-Alder reaction at relatively low energy barrier. Tetranitroethylene could react with the designed dienes much more easily than other dienophiles, and was employed to further design 29 new bridge-ring energetic compounds. Due to high heat of formation, density and oxygen balance, all designed bridge-ring energetic compounds have outstanding detonation performance, 16 of them have higher energy than HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocine) and 2 others even possess comparative energy with the representative of high energy compounds CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane). The predicted average h50 value of these bridge-ring energetic compounds is 83 cm, showing their low impact sensitivity. The NH2 groups could obviously impel the proceeding of Diels-Alder reactions, but would slightly decrease the energy and sensitivity performance. In all, the new designed bridge-ring compounds have both high energy and low sensitivity, and may be produced through Diels-Alder reactions at relatively low energy barrier. This paper may be helpful for the theoretical design and experiment synthesis of new advanced insensitive high energy compounds. 相似文献
776.
This paper presents a comprehensive review of the research studies on direct energy system effect on aircraft composite structures to develop a good understanding of state-of-the-art research and devel-opment in this area. The review begins with the application of composite materials in the aircraft structures and highlights their particular areas of application and limitations. An overview of directed energy system is given. Some of the commonly used systems in this category are discussed and the working principles of laser energy systems are described. The experimental and numerical studies re-ported regarding the aircraft composite structures subject to the effect of directed energy systems, especially the laser systems are reviewed in detail. In particularly, the general effects of laser systems and the relevant damage mechanisms against the composite structures are reported. The review draws attention to the recent research and findings in this field and is expected to guide engineers/researchers in future theoretical, numerical, and experimental studies. 相似文献
777.
为降低视频烟雾检测中的虚警率和提升检测效率,提出YdUaVa颜色模型,该模型可以表征烟雾的空间域分布特性和时间域变化特性。利用该颜色模型快速筛选出疑似烟雾图像块,降低虚警率和提升运算效率。提出改进的MobileNetV3网络结构,用于提取图像深度特征并对疑似烟雾图像块进行分类识别,检测视频中是否存在烟雾。视频烟雾检测仿真结果表明:该方法准确率和检测帧率高,虚警率低。 相似文献
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