N+1式高频电力开关电源设计

探讨了N＋1式高频电力开关电源的组成和工作原理。开关电源由监控模块和整流模块组成,重点研究了均流技术和开关电源的抗干扰措施,论述了整流模块数量N＋1的选择。实际运行证明,N＋1式高频电力开关电源工作可靠,达到了预期效果。     

耐压液舱区域耐压船体强度的研究

本文把带纵骨实肋板式耐压液舱和对应的耐压船体看成一弹性整体,求解了耐压液舱区耐压船体的应力响应,并通过塑性极限分析,求得了其极限承载能力。理论分析与有限元计算及实验结果相比较,吻合较好。     

变结构控制及其在综合火力/飞行控制系统中应用初探

首先介绍了综合火力/飞行控制系统和变结构控制的基本原理及其特点,然后对如何应用变结构控制理论进行火飞控制器设计进行了探讨。     

电子装备模拟印制板电路故障自动诊断系统研究

为提高电子装备模拟印制板电路故障诊断的速度,本文使用直流故障字典法原理,运用区域性故障定位方法,改进器件模型和电路描述程序,设计了模拟印制板电路故障自动诊断系统。     

简化的块变步长自适应算法

本文提出了一项特别适用于进行实时信号处理、可作为评估自适应算法性能的新指标——收敛时间。然后依据此指标,提出了一种简化的块变步长(SBVS)自适应算法,并导出了它的频域实现。计算机模拟结果表明,该算法在性能上优于BLMS 算法。     

Prolog 编译器中暂时变量分配方法研究

文中研究对prolog 编译器的暂时变量的分配,介绍了回溯分配法,着重介绍了一种高效的无回溯分配法的实现原理及其优点。     

雷达综合灵敏度测试方法研究

本文提出雷达接收微弱信号能力的新拟指标——雷达综合灵敏度。给出其在不解体状态下的测试方法,并对测试误差进行了分析。     

A melt-cast Duan-Zhang-Kim mesoscopic reaction rate model and experiment for shock initiation of melt-cast explosives

A melt-cast Duan-Zhang-Kim (DZK) mesoscopic reaction rate model is developed for the shock initiation of melt-cast explosives based on the pore collapse hot-spot ignition mechanism. A series of shock initiation experiments was performed for the Comp B melt-cast explosive to estimate effects of the loading pressure and the particle size of granular explosive component, and the mesoscopic model is validated against the experimental data. Further numerical simulations indicate that the initial density and formula proportion greatly affect the hot-spot ignition of melt-cast explosives.     

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.     

Partial penetration of annular grooved projectiles impacting ductile metal targets

Changing and optimizing the projectile nose shape is an important way to achieve specific ballistic performance. One special ballistic performance is the embedding effect, which can achieve a delayed high-explosive reaction on the target surface. This embedding effect includes a rebound phase that is significantly different from the traditional penetration process. To better study embedment behavior, this study proposed a novel nose shape called an annular grooved projectile and defined its interaction process with the ductile metal plate as partial penetration. Specifically, we conducted a series of low-velocity-ballistic tests in which these steel projectiles were used to strike 16-mm-thick target plates made with 2024-O aluminum alloy. We observed the dynamic evolution characteristics of this aluminum alloy near the impact craters and analyzed these characteristics by corresponding cross-sectional views and numerical simulations. The results indicated that the penetration resistance had a brief decrease that was influenced by its groove structure, but then it increased significantly-that is, the fluctuation of penetration resistance was affected by the irregular nose shape. Moreover, we visualized the distribution of the material in the groove and its inflow process through the rheology lines in microscopic tests and the highlighted mesh lines in simulations. The combination of these phenomena revealed the embed-ment mechanism of the annular grooved projectile and optimized the design of the groove shape to achieve a more firm embedment performance. The embedment was achieved primarily by the target material filled in the groove structure. Therefore, preventing the shear failure that occurred on the filling material was key to achieving this embedding effect.