耦合杀伤区射击次数与舰艇间距分析

研究了舰艇编队协同防空中满足一阶耦合杀伤区对来袭目标射击次数要求的编队舰舰间距配置问题。依据耦合杀伤区的概念,运用几何三角关系和解析法分析了一阶和二阶耦合杀伤区的纵深计算方法。并对给定杀伤区纵深的单舰和协同舰射击次数进行了研究,给出了射击次数模型及受目标投弹圈影响的耦合杀伤区纵深约束条件。对不同入射舷角的目标、不同速度的导弹类目标和不同高度、速度的飞机类目标3种情况下的射击次数与间距关系进行了仿真,得到了一些有益的结论,对编队近程防空队形的间距配置具有指导意义。     

异类传感器信息融合的分布式滤波算法

基于联邦滤波算法,对雷达/红外双模导引头数据融合算法进行了研究,给出了基于雷达/红外双模导引头跟踪系统的结构及算法模型.针对典型工作状况参数,对匀速、匀加速、机动等目标运动状态进行了蒙特卡罗追踪仿真.仿真结果表明:基于联邦滤波的分布式融合跟踪算法,对各种目标运动状态下的位置、速度跟踪精度和抗干扰能力都相对于雷达单模跟踪的较好.     

进气口位置和进气体积流量对油罐油气惰化置换效率的影响

采用机械通风方式对油罐油气进行处理,具有安全性差、通风时间长和效率低下的缺点;利用燃惰气对油罐油气进行处理,可较好地克服上述缺点。在前期研究的基础上,设计模拟实验台架,以燃惰气为介质,实验研究进气口位置和进气体积流量对燃惰气惰化置换油罐油气的影响。     

Interval uncertain optimization for damping fluctuation of asegmented electromagnetic buffer under intensive impact load

Aiming at the problems of demagnetization effect of electromagnetic buffer (EMB) caused by high ve-locity under intensive impact load and the difficulty and error of machining composite thin-walled long tube, a segmented EMB is proposed. The inner tube and air-gap are divided into initial segments and the traversing segments. Through theoretical analysis, impact test and simulation, it can be found that the RRF curve has two peaks. Firstly, in order to reduce the resultant resistance force (RRF) peaks, the sensitivity analysis based on optimal Latin hypercube design (OLHD) and polynomial regression was performed. The results show that the smallest contribution ratio to the dynamic response is the seventh and ninth segments of the inner tube, which are less than 1％. Then, fully considering the uncertain factors, important parameters are selected for uncertain optimization after sensitivity analysis. The in-terval order and interval probability degree methods are used to establish interval uncertain optimiza-tion model of the RRF considering robustness. The model was solved using an interval nested optimization method based on radial basis function (RBF) neural network. Finally, the Pareto front is obtained and numerical simulation is performed to verify the optimal value. It indicates that the two kinds of RRF peak is obviously reduced, and the optimization object and strategy are effective.     

The effect of al particle size on thermal decomposition,mechanical strength and sensitivity of Al/ZrH2/PTFE composite

To study the thermal decomposition of Al/ZrH2/PTFE with different Al particle size as well as mechanical strength and impact sensitivity under medium and low strain rates, molding-vacuum sintering was adopted to prepare four groups of power materials and cylindrical specimens with different Al particle size. The active decomposition temperature of ZrH2 was obtained by TG-DSC, and the quasi-static me-chanics/reaction characteristics as well as the impact sensitivity of the specimen were studied respec-tively by quasi-static compression and drop-hammer test. The results show that the yield strength of the material decreased with the increase of the Al particle size, while the compressive strength, failure strain and toughness increased first and then decreased, which reached the maximum values of 116.61 MPa, 191％, and 119.9 MJ/m respectively when the Al particle size is 12—14μm because of particle size grading. The specimens with the highest strength and toughness formed circumferential open cracks and reacted partly when pressed. Those with developmental cracks formed inside did not react. It is considered that fracture of specimens first triggered initial reaction between Al and PTFE to release an amount of heat. Then ZrH2 was activated and decomposed, and participated in subsequent reaction to generate ZrC. The impact sensitivity of the specimens decreased with the increase of Al particle size.     

Pressure relief of underground ammunition storage under missile accidental ignition

Safety of underground ammunition storage is an important issue, especially during the accidental ignition of missiles. This work investigates the pressure and temperature distribution of the multi-layer underground ammunition storage with a pressure relief duct during the accidental ignition process of the missile. A large-scale experiment was carried out using a multi-layered restricted space with a pressure relief duct to simulate the underground ammunition store and a solid rocket motor to simulate the accidental ignition of the missile. The results show that when the motor gas mass flow increased by 5.6 times, the maximum pressure of the ammunition storage increased by 5.87 times. At a certain motor flow rate, when the pressure relief exhaust area at the end of the relief duct was reduced by 1/2, the maximum pressure on the first layer did not change. But the rate of pressure relief was reduced and the time delayed for the pressure of ammunition store to drop to zero. In this experiment, when the motor ignition position was located in to the third layer ammunition chamber, the maximum pressure was reduced by 32.9％ and also reduced the rate of change of pressure. In addition, for the experimental conditions, the theoretical analysis of the pressure relief of the ammunition storage is given by a simplified model. Based on the findings, some suggestions to the safety protection design of ammunition store are proposed.     

军事领域细粒度识别技术与应用

战争的信息化程度不断加深对军事侦察提出了更高要求。军事目标识别作为军事侦察的主要任务之一,需要能够处理细粒度军事目标,为人员提供更加详细的目标信息。但传统的粗粒度目标识别方法无法得到目标的细粒度信息。因此,如何识别细粒度目标成为目前军事侦察亟需解决的问题。针对该问题,本文结合军事领域的实际需求,对细粒度识别技术的发展现状进行了分析,提出了军事领域细粒度识别技术应用流程的数据集构建、模型设计和终端部署三个阶段,同时,从无人机侦察、遥感侦察和单兵侦察三个方向分析了细粒度识别的应用前景。经过分析,军事领域细粒度识别技术已经具备实际运用条件,具备良好的应用价值。     

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.     

Blast resistance evaluation of urban utility tunnel reinforced with BFRP bars

To improve corrosion-resistance of shallow-buried concrete urban utility tunnels(UUTs),basalt fiber reinforced polymer(BFRP)bars are applied to reinforce UUTs.As the UUT must have excellent survival capability under accidental explosions,a shallow-buried BFRP bars reinforced UUT(BBRU)was designed and constructed.Repetitive blast experiments were carried out on this BBRU.Dynamic responses,damage evolutions and failure styles of the BBRU under repetitive explosions were revealed.The tunnel roof is the most vulnerable component and longitudinal cracks develop along the tunnel.When the scaled distance is larger than 1.10 m/kg1/3,no cracks are observed in the experiments.When the BBRU is severely damaged,there are five cracks forming and developing along the roof.The roof is simplified as a clamped-supported one-way slab,proved by the observation that the maximum strain of the transverse bar is much larger than that of the longitudinal bar.Dynamic responses of the roof slab are predicted by dynamic Euler beam theory,which can consistently predict the roof displacement under large-scaled-distance explosion.Compared with the UUT reinforced with steel bars,the BBRU has advantages in blast resistance with smaller deflections and more evenly-distributed cracks when the scaled distance is smaller than 1.260 m/kg1/3 and the steel bars enter plastic state.Longer elastic defamation of the BFRP bars endows the UUT more excellent blast resistance under small-scaled-distance explosions.     

A novel launch dynamics measurement system for multiple launch rocket system and comparative analysis with numerical simulations

In this paper,a novel launch dynamics measurement system based on the photoelectric sensor pair is built.The actual muzzle time(i.e.a time duration that originates from the initial movement to the rocket's departure from the muzzle)and the muzzle velocity are measured.Compared with the classical methods,the actual muzzle time is obtained by eliminating the ignition delay.The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems.The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods,which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.