基于蒙特卡罗仿真评价车辆装备预防性维修间隔期方法

为解决在理论研究阶段利用试行方法评价车辆装备关键零部件预防性维修间隔期可操作性较低的问题, 提出基于蒙特卡罗仿真评估预防性维修间隔期的方法和流程。选取评价车辆装备关键零部件预防性维修间隔期效果 的指标,阐述车辆装备关键零部件定期更换和定期检测策略,以评价制动器摩擦盘预防性维修间隔期为例进行分析 验证。结果表明,该方法能有效对车辆装备预防性维修间隔期维修效能作出定量评价。     

导弹测试设备电路板备件预测方法

针对导弹测试设备电路板的特性,从备件不可修、寿命服从指数分布、泊松分布经验模型和基于备件保障度的角度出发,提出了对其备件进行预测的4种方法,其中基于备件保障度的预测模型又可分为单不可修寿命服从负指数分布部件和多不可修寿命服从负指数分布部件．     

一种基于可靠度约束的分阶段等周期预防性维修模型研究

为保持装备寿命周期的运行可靠性,针对周期预防性维修模型和顺序预防性维修模型的优缺点,结合装备维护保养实际,提出3阶段等周期预防性维修模型。以可靠度约束条件下的装备寿命周期最小费率为优化目标,建立了周期预防性维修模型、顺序预防性维修模型和3阶段等周期预防性维修模型,从而得到各计算模型装备寿命周期的最优预防性维修次数和维修间隔期。结果表明,在同等条件下,3阶段等周期预防性维修模型既能保持装备寿命周期内较高的可靠性和较低的费率,又能紧密结合维修操作实际,具有良好的应用可行性和推广性。     

改进性维修及间隔期调整与效能评价研究

结合装备大修,对现有装备进行适当的改进性维修,以提升装备性能改善,装备使用与保障要求,改进后需要适当调整维修间隔期并对改进性维修的效能进行评判;在总结了改进性维修的现状以及存在的问题,改进性维修的一般原则,分类方式及步骤方法的基础上,提出了维修间隔期的调整方法,并用改进性维修后装备可用度增长的百分比和改进性维修费用增长百分比的比值大小作为改进性维修的评价,根据评价的结果选择较好的调整方案。     

基于无失效数据的飞行训练导弹弹上设备可靠性分析

根据A型空地导弹飞行训练弹在使用过程中获得的使用数据,假设弹上设备模拟器和导引头的寿命分别服从指数分布和正态分布,采用无失效数据的处理方法分别评估了模拟器和导引头的可靠性水平,为训练弹弹上设备的维修和定寿提供重要依据。     

定时维修间隔期的优化计算方法

分析了现有装甲装备定时维修可能出现维修过剩的问题,阐述了合理确定定时维修间隔期的重要性,对以费用最小为目标的定时维修间隔期模型进行了研究,实现了优化定时维修间隔期的目的。     

导弹武器装备备件数量计算方法研究

基于导弹装备备件储存不合理的现状，探讨了寿命服从指数分布、正志分布和威布尔分布的导弹部件的初始备件需求量，以及可修复件和不可修复件的后续备件数量的计算方法．讨论了备件保障和战备完好性的关系，指出按战备完好性要求配置备件是科学、合理的方法．     

基于可靠性的装备预防性维修支持系统

基于可靠性的装备预防性维修支持系统采用C/S分布式结构,由用户、应用和支撑三层组成,包括事后维修、定时和视情况预防性维修.系统知识库包括可靠性、维修性、经济性、测试性、维修间隔期算法、维修方案及控制等规则库.输入静动态参数后进行预处理,调用推理计算系统,确定维修方式和类型,调用有关的规则,算出合理的维修间隔期.     

多级保障设备寿命期内的可用度模型

针对具有三级维修机构保障的复杂设备,在小修修复如旧、中修大修均可使设备年轻固定时间的假设下,通过对设备使用和修理流程分析,给出了设备寿命期内的使用与修理状态转移图,建立了设备寿命期内的维修间隔期与可用度关系模型,求出了设备在固定的维修间隔期和一定维修转换规则下的平均可用度。案例分析得到了使可用度达到最大时的设备最佳维修间隔期,并通过与大修修复如新进行比较,说明了模型的适用性与灵敏性,可为设备维修决策提供依据。     

任意分布单元可用度计算的微分方程方法

对于故障概率密度和修复概率密度服从指数分布的可修复单元,可用度可以采用拉普拉斯变换得到解析解,但是导弹武器系统中,单元并非总是服从指数分布,采用拉普拉斯变换难以求解.文中通过求解微分方程组,提出了故障概率密度及修复概率密度服从常见分布的可用度计算方法,并且以故障概率密度服从指数分布.修复概率密度服从正态分布为例,分析了制导雷达的故障频率、修复频率及可用度的变化规律.所提方法便于工程应用.     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.