自由电子激光互作用机制的研究

本文从电子的自发辐射能谱公式出发,发现电子的自发辐射频率与以往导出的自由电子激光受激辐射频率是一致的。由此得到:自发辐射频率的线谱化,使某频率的入射电磁波对电子自发辐射某一相应模式进行选择性互作用,从而实现受激辐射。并且,自然地得到了自由电子激光的高次模式。     

高层体系结构(HLA)的开发与构建

从ＤＩＳ的局限性及不足出发,简要说明了构建和开发ＨＬＡ的可行性和必要性;重点论述了ＨＬＡ的结构、规则、接口规范、对象模型模板（ＯＭＴ）及ＳＯＭ 和ＦＯＭ 的构建步骤     

21世纪无人机关键技术

无人机因其独特而优异的战术性能,在近几次现代局部战争中得到了越来越广泛的应用,执行的任务也越来越多。从未来无人机的军事需求及其战术性能入手,结合技术发展趋势和发展可行性,对未来无人机发展需要的一些关键技术进行了分析研究,这些关键技术对提高未来无人机的战术性能具有重要作用。     

海战场信息系统和武器系统综合仿真技术研究

本文分析了海战场信息系统仿真的特点,介绍了可以应用于海战场信息系统和武器系统综合仿真的高层体系结构(HLA)技术,描述了澳大利亚国防科学与技术组织(DSTO)基于HLA技术的虚拟舰艇概念和潜在的应用,以及虚拟舰艇结构和层次化联邦共同体概念的设计方法。     

Theoretical design of new bridge-ring insensitive high energy compounds by selected normal Diels-Alder reactions between NH2-substituted oxazoles and NO2/NF2/NHNO2-substituted ethylenes/acetylenes

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.     

Robust cubature Kalman filter method for the nonlinear alignment of SINS

Nonlinear initial alignment is a significant research topic for strapdown inertial navigation system(SINS).Cubature Kalman filter(CKF)is a popular tool for nonlinear initial alignment.Standard CKF assumes that the statics of the observation noise are pre-given before the filtering process.Therefore,any unpredicted outliers in observation noise will decrease the stability of the filter.In view of this problem,improved CKF method with robustness is proposed.Multiple fading factors are introduced to rescale the obser-vation noise covariance.Then the update stage of the filter can be autonomously tuned,and if there are outliers exist in the observations,the update should be less weighted.Under the Gaussian assumption of KF,the Mahalanobis distance of the innovation vector is supposed to be Chi-square distributed.Therefore a judging index based on Chi-square test is designed to detect the noise outliers,determining whether the fading tune are required.The proposed method is applied in the nonlinear alignment of SINS,and vehicle experiment proves the effective of the proposed method.     

Dynamic necking of a near α titanium alloy at high strain rates:Experiments and modelling

The tensile behaviour of near α Ti3Al2.5 V alloy, conceived for applications in aerospace and automotive engineering, is characterized from quasi-static to high strain rates. The material is found to present noticeable strain rate sensitivity. The dynamic true strain rate in the necking cross-section reaches values up to ten times higher than the nominal strain rate. It is also observed that beyond necking the dynamic true stress-strain curves present limited rate dependence. The experimental results at different strain rates are used to determine a suitable constitutive model for finite element simulations of the dynamic tensile tests. The model predicts the experimentally macroscopic force-time response, true stress-strain response and effective strain rate evolution with good agreement.     

Supercritical carbon dioxide as a new working medium for pneumatic launch: A theoretical study

Compared with the conventionally gaseous or liquid working media, the specific internal energy of supercritical carbon dioxide (SCD) is higher at the same temperature and pressure, and the critical temperature of carbon dioxide is close to room temperature, making SCD a potential new working medium for pneumatic launch. To analyze the feasibility of this conception, an analytical model of a pneumatic catapult is established on basis of the conservations of mass and energy. The model consists of a high-pressure chamber and a low-pressure chamber connected by multiple valves, and there is a movable piston in the low-pressure chamber that can push an aircraft to accelerate. The effects of the launch readiness state of SCD in the high-pressure chamber, the initial volume of the low-pressure chamber and the valve control on the movement of the aircraft are analyzed. It is found that there is a restrictive relation between the temperature and pressure of the launch readiness state of SCD, i.e., there is a maximum allowable launch readiness pressure when the launch readiness temperature is fixed. If this restrictive relation is not satisfied, the working medium in the low-pressure chamber will drop to its triple point within a few milliseconds, leading to a launch failure. Owing to this restrictive relation, there is an optimal launch readiness state of SCD with the highest working capacity for any allowable launch readiness temperature. The pressure of the low-pressure chamber will decrease significantly as the initial volume increases, leading to a decreased acceleration of the aircraft. The ac-celeration can be controlled below a critical value by a designed sequential blasting technique of multiple valves. The calculated results show that a 500 kg aircraft can be accelerated from 0 to 58 m/s in 0.9 s with 36 kg of carbon dioxide. This research provides a new technique for the controllable cold launch of an aircraft.     

基于HLA的信息化陆战场多传感器仿真系统研究

多传感器是实现未来信息化陆战场“网络中心战”概念的一组必要的装备系统。着眼于为信息化陆战场信息采集与信息融合等方面项目先期概念技术演示提供仿真平台,提出了多传感器系统模型,重点研究了基于HLA的信息化陆战场多传感器仿真系统的总体框架及其设计,为该仿真系统的建立和仿真实施提供了技术支持。