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171.
本文认为,《江泽民创新思想研究》系统地阐述了江泽民的创新观及其内涵、特征和意义,较好地反映出江泽民创新思想的核心内涵和立体思维,全书构思新颖、结构严谨合理,是一部研究党永葆生机源泉的力作。 相似文献
172.
173.
This paper reports on a study using the available oil monitoring information, such as the data obtained using the Spectrometric Oil Analysis Programme (SOAP), to predict the residual life of a set of aircraft engines. The relationship between oil monitoring information and the residual life is established using the concept of the proportional residual, which states that the predicted residual life may be proportional to the wear increment measured by the oil analysis programmes. Assuming such a relationship between wear and the residual life exists, we formulated a recursive prediction model for the item's residual life given measured oil monitoring information to date. A set of censored life data of 30 aircraft engines (right censored due to preventive overhaul) along with the history of their monitored metal concentration information are available to us. The metal concentration information includes many variables, such as Fe, Cu, Al, etc.; not all of them are useful, and some of them may be correlated. The principal component analysis (PCA) has been adopted to reduce the dimension of the original data set and to produce a new set of uncorrelated variables, which we shall use in the prediction model. The procedure associated with estimating model parameters is discussed. The model is fitted to the actual SOAP data from the aircraft engines, and the goodness‐of‐fit test has been carried out. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
174.
做好新形势下院校安全保密工作,是当前军队院校建设的一项重要任务.我们必须着眼军队院校的地位作用和职能任务,认真研究军队院校的特点及规律,不断提高工作的针对性和实效性,确保院校安全和稳定. 相似文献
175.
本文分析了C4ISR系统的建模特点,对当前主流体系结构模型开发方法进行了比较,提出了运用Rational统一过程(RUP)开发DoDAF体系结构视图产品,并分析了其可行性。结合航空兵作战的特点,采用Rational ROSE建模工具开发了的相关视图产品,描述了航空兵作战过程,证明了RUP对体系结构的开发有着良好的支持作用。 相似文献
176.
Single unmanned aerial vehicle (UAV) multitasking plays an important role in multiple UAVs cooperative control, which is as well as the most complicated and hardest part. This paper establishes a three-dimensional topographical map, and an improved adaptive differential evolution (IADE) algorithm is proposed for single UAV multitasking. As an optimized problem, the efficiency of using standard differential evolution to obtain the global optimal solution is very low to avoid this problem. Therefore, the algorithm adopts the mutation factor and crossover factor into dynamic adaptive functions, which makes the crossover factor and variation factor can be adjusted with the number of population iteration and individual fitness value, letting the algorithm exploration and development more reasonable. The experimental results implicate that the IADE algorithm has better performance, higher convergence and efficiency to solve the multitasking problem compared with other algorithms. 相似文献
177.
Reactive Materials (RMs), a new material with structural and energy release characteristics under shock-induced chemical reactions, are promising in extensive applications in national defense and military fields. They can increase the lethality of warheads due to their dual functionality. This paper focuses on the energy release characteristics of RM casings prepared by alloy melting and casting process under explosive loading. Explosion experiments of RM and conventional 2A12 aluminum alloy casings were conducted in free field to capture the explosive fireballs, temperature distribution, peak overpressure of the air shock wave and the fracture morphology of fragments of reactive material (RM) warhead casings by using high-speed camera, infrared thermal imager temperature and peak overpressure testing and scanning electron microscope. Results showed that an increase of both the fireball temperature and air shock wave were observed in all RM casings compared to conventional 2A12 aluminum ally casings. The RM casings can improve the peak overpressure of the air shock wave under explosion loading, though the results are different with different charge ratios. According to the energy release characteristics of the RM, increasing the thickness of RM casings will increase the peak overpressure of the near-field air shock wave, while reducing the thickness will increase the peak overpressure of the far-field air shock wave. 相似文献
178.
Chain damage is a new phenomenon that occurs when a reactive jet impacts and penetrates multi-spaced plates.The reactive jet produces mechanical perforations on the spaced plates by its kinetic energy(KE),and then results in unusual chain rupturing effects and excessive structural damage on the spaced plates by its deflagration reaction.In the present study,the chain damage behavior is initially demonstrated by experiments.The reactive liners,composed of 26 wt%Al and 74 wt%PTFE,are fabricated through a pressing and sintering process.Three reactive liner thicknesses of 0.08 CD,0.10 CD and 0.12 CD(charge diameter)are chosen to carry out the chain damage experiments.The results show a chain rupturing phenomenon caused by reactive jet.The constant reaction delay time and the different penetration velocities of reactive jets from liners with different thicknesses result in the variation of the deflagration position,which consequently determines the number of ruptured plates behind the armor.Then,the finite-element code AUTODYN-3D has been used to simulate the kinetic energy only-induced rupturing effects on plates,based on the mechanism of behind armor debris(BAD).The significant discrepancies between simulations and experiments indicate that one enhanced damage mechanism,the behind armor blast(BAB),has acted on the ruptured plates.Finally,a theoretical model is used to consider the BAB-induced enhancement,and the analysis shows that the rupturing area on aluminum plates depends strongly upon the KE only-induced pre-perforations,the mass of reactive materials,and the thickness of plates. 相似文献
179.
单[6-脱氧(1,10癸二硫醇)巯基]β-环糊精的合成方法研究 总被引:1,自引:0,他引:1
制备合成单[6-脱氧(1,10癸二硫醇)巯基]β-环糊精,结合产物的。^1H NMR,^13C HMR分析,推测了可能的反应机理,初步讨论了其在制备传感器敏感膜材料方面的应用前景。 相似文献
180.
研究分析了描述重气扩散过程的多种现有模型的特点,选择以浅层模型为基础,设计开发了CH2Cl2模拟弹爆炸扩散过程模拟分析的软件系统.通过与试验蛄果对比.表明了计算机模拟分析的有效性,为远距离红外检测系统提供了辅助技术基础. 相似文献