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111.
简要介绍了几种汽车轮胎安全技术,分析了目前阻车装备原理、特点及不足,根据国内外情况提出几种新的阻车原理和技术作为下一步研究重点,最后指出,应从影响驾驶的各个因素来研究不同的阻车原理和技术,创造出多种阻车迫停技术、手段来满足实战需求。 相似文献
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新疆高校师范专业少数民族大学生思想政治教育工作探讨 总被引:1,自引:0,他引:1
加强高校师范专业少数民族大学生思想政治教育是国家和民族发展的长远需要。本文对新疆高校师范专业少数民族大学生思想政治教育工作中存在的如思想政治教育方式不当、方法及机制不健全等问题进行了分析,并在此基础上提出了相应的对策,以期促进新疆师范专业少数民族大学生的思想政治教育工作的发展。 相似文献
114.
The quick response (QR) system that can cope with demand volatility by shortening lead time has been well studied in the literature. Much of the existing literature assumes implicitly or explicitly that the manufacturers under QR can always meet the demand because the production capacity is always sufficient. However, when the order comes with a short lead time under QR, availability of the manufacturer's production capacity is not guaranteed. This motivates us to explore QR in supply chains with stochastic production capacity. Specifically, we study QR in a two-echelon supply chain with Bayesian demand information updating. We consider the situation where the manufacturer's production capacity under QR is uncertain. We first explore how stochastic production capacity affects supply chain decisions and QR implementation. We then incorporate the manufacturer's ability to expand capacity into the model. We explore how the manufacturer determines the optimal capacity expansion decision, and the value of such an ability to the supply chain and its agents. Finally, we extend the model to the two-stage two-ordering case and derive the optimal ordering policy by dynamic programming. We compare the single-ordering and two-ordering cases to generate additional managerial insights about how ordering flexibility affects QR when production capacity is stochastic. We also explore the transparent supply chain and find that our main results still hold. 相似文献
115.
We study the competition problem of purchase and multiretrieval of perishable seasonal produce, where wholesalers purchase and stock their products in the first period, and then retrieve and sell them in subsequent periods. We first consider the duopoly case and assume that the prices are exogenous and fluctuate. In each period, after the price realization, the wholesalers retrieve some stock from their warehouses to satisfy their demands. One wholesaler's unsatisfied customers can switch to another and be satisfied by its left retrieved products. Any unsold retrieved stock has no salvage value and any unsatisfied demand is lost. The unretrieved stock is carried to the next period at a perishable rate. The wholesalers compete for the substitute demand by determining their own purchase and retrieval quantities. We show the existence and uniqueness of a pure-strategy Nash equilibrium, and that the Nash equilibrium strategy has the simple “sell-down-to” structure. We also consider the general N-person game and show the existence of the Nash equilibrium, and characterize the structure of the equilibrium strategy for the symmetric case. In addition, we consider the case with endogenous prices, and show that the problem reduces to a repeated newsvendor game with price and inventory competition. We derive the conditions under which a unique Nash equilibrium exists and characterize the equilibrium strategy. Finally, we conduct numerical studies to examine the impacts of the model parameters on the equilibrium outcomes and to generate managerial insights. 相似文献
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针对气动光学数字图像校正在工程应用方面的问题,对高速导弹末制导过程中气动光学效应条件下时间序列失真图像校正算法模型进行梳理,分析了现有校正算法工程应用中存在的问题,提出了更为注重建立先验知识的数字图像校正的工程应用方法.在此基础上以窗口传输效应为例,建立了能满足工程应用适用性和实时性要求的窗口传输效应校正模型,并进行了数学仿真,给出了像偏移校正仿真结果,探索了气动光学数字图像校正工程应用方法. 相似文献
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三、美国军事转型的主要特性(一)顶层设计,追求“跨越一代”的规划效果美国军事转型的最显著特点就是谋求跨越时代的超前性,这种谋求超前性的强烈欲望,一方面来自美国人强烈的时代感和机遇意识,另一方面来自他们居安思危的忧患意识。信息技术群的迅猛发展,深刻改变着社会生活的 相似文献
119.
随着恐怖主义愈演愈烈,"反恐"成为当今世界各国军事安全部门的中心任务.使用分类型可视化工具Parallel Sets分析国际恐怖主义数据库中多属性分类值间的关系,揭示数据库中的隐性信息,并针对Parallel Sets任意排列分类值产生较多交叉的不足,提出带降势的启发式分类值布局算法,自动优化分类值布局顺序,减轻视图中... 相似文献
120.
Li-zhi Xu Cheng-xin Du Chun Cheng Xiao-dong Wang Jiang-bo Wang Zhong-hua Du Guang-fa Gao 《防务技术》2021,17(3):859-873
When a penetrator with enhanced lateral effect (PELE) impacts on a reinforced concrete (RC) target, the target is damaged with a large opening. An understanding of how PELE projectile parameters affect the opening dimension, is essential for effective design of the PELE projectile. In this study, under the condition that the impact velocity and target parameters (strength and thickness) were fixed values, the important influence factors of the PELE (jacket wall thickness B, jacket material strength Y1, filling material strength Y2 and angle of monolithic jacketθ) were determined by a dimensional analysis. Tests and simulations of the PELE penetrating the RC target were conducted to analyze the influence of these factors on opening diameter ((D), an equivalent diameter under relative kinetic energy). Based on the test and simulation results, it is found that the influence of these factors B, Y1 andθon the deformation mode of the jacket shows a similar trend:as values of the three factors decrease, the jacket deforms from small bending deformation to large one, and then to curling deformation. This causes the opening diameter to first increase with the decrease of these three factors, and then decreases. It is well known that the bending resistance of the jacket is related to these factors B, Y1 andθ. Therefore, a plastic limit bending moment (M0) of the jacket was quoted to characterize the influence of these factors on the bending deformation of the jacket and the opening diameter of the target. The influence factor Y2 causes (D) to first increase with the increase of Y2, and then decreases. A formula was developed to predict the opening diameter, whose influence parameters were considered in a dimensionless way. It has been shown that the dimensionless opening diameter (D)/d1 is dependent on two dimensionless parameters Q = (d31fc/M0) and G = (fc/Y2), where d1 and fc are the outer diameter of the projectile and the compressive strength of the target, respectively. 相似文献