海军要地防空阵地优化配置分析

在要地防卫作战中,阵地优化配置对如何减少火力损失和最大程度发挥武器效能起到关键作用。文章较为全面的阐述了阵地优化配置的重要意义,分析了阵地优化配置的基本要求,以及进行优化配置时需要考虑的影响因素,并提出了选取优化配置方案的整体思想,为今后在优化模型选取方面做进一步研究提供了思路。在实际作战中,进行阵地优化配置时,还应根据作战条件,做适当改进。     

虚拟雷达信号环境构建方法研究

简要分析了虚拟雷达信号环境构建的方法,结合雷达信号环境基本要素完成对辐射源模型的构建,最后结合仿真技术定量研究了构建战场大区域、雷达信号辐射源的电磁环境仿真实现,试验结果表明,该方法切实可行,具有实际意义。     

光学扫描仪在整车逆向开发过程中的应用

基于ATOS、Tritop原理、优点,结合逆向开发方式在汽车开发中的主要流程,描述了ATOS、Tritop的具体应用。     

沉降及位移监测对软土路基填筑速度的指导

结合实际工程,详细介绍了软土路基监测程序和观测点的设置原则。指出软土路基的沉降和侧向位移的监测不仅可以确定路基的预压时间和路面铺筑时机,还可以指导路基的填筑速度,并评价软土地基的处理方法。     

流溪河大桥分段切割拆除吊点选取的分析

广清高速公路扩建工程流溪河大桥主桥预应力混凝土箱梁采用分段切割的方法进行拆除,并利用架桥机将拆除后的箱梁吊运至陆上进行破碎处理.运用有限元结构分析软件ANSYS对不同吊点方式下箱梁应力应变进行分析,从而选取合理的吊点方式,以确保桥梁拆除过程中的安全.     

Theoretical Formula for Calculating Negative Skin Friction of Pile in Layered Soil and Its Application

Based on Zeevaert's method, a theoretical formula was developed to calculate the negative skin friction of pile in layered soil. For practical purpose,a cut-and-try method was proposed to determine neutral point. Case studies indicate that the total calculated negative skin friction was in agreement with the measured one, which verifies the feasibility and practicability of theoretical formula. Furthermore, the methods for calculating efficiency factor of drag load and settlement were also given.     

浅谈冬季公路雪阻的防治

简要介绍了冬季公路预防风雪流常用的几类设施的适应性及设置要求。对雪阻的治理应综合考虑各种因素 ,因地制宜     

The impacts of strait and canal blockages on the transportation costs of the Chinese fleet in the shipping network

ABSTRACT

Straits and canals have always served as key nodes in shipping networks. The blockage of a strait or canal will lead to ship deviations and increased transportation costs. To measure this impact on the Chinese fleet, our study develops a mathematical model that is based on a programming formulation. Each strait or canal is assumed to be blocked in turn, and the increased transportation costs for the Chinese fleet in different scenarios are calculated and compared using the proposed programming formulation in order to measure the impact of the blocked strait or canal on the Chinese fleet. Larger increases in transportation costs have greater impacts on the fleet. The results show that a blockage of the Strait of Hormuz would have the greatest impact of all straits and canals; it would cause the Chinese fleet to lose a portion of its import and export market, and such a blockage cannot be addressed through ship deviations. Based upon increased transportation costs, the four straits or canals that would have the greatest impact if blocked are the Mandeb Strait, the Suez Canal, the Sunda Strait and the English Channel.     

信号交叉口混合交通流协调优化方法研究

简述了我国信号交叉口混合交通流特征和国内外研究现状,针对我国典型4相位(双向左转)信号控制交叉口,运用包括迟起、早断的信号控制方法,给出了行人和非机动车相应的绿灯间隔时间计算公式和信号相位配时方法,并结合南京市太平北路-珠江路交叉口的实测数据进行了计算,计算结果表明,通过设置行人、非机动车专用信号,能够有效避开混合交通流在交叉口的冲突,提高了交叉口的交通安全性及其通行能力,应用前景较为广泛。同时,还为城市区域信号控制技术和城市智能交通系统(ITS)的研究与开发提供了理论依据。     

大跨度桥梁结构有限元抗震分析的多点输入法

本文考虑地震动场的空间相关性 ,对大跨度桥梁结构在多点输入地震作用模式下的抗震分析方法进行了研究。该法由响应量幅值的平方直接求得特定频率点 ,该响应量的功率谱值 ,进而可求得其均方值等统计特性 ,与传统的均匀输入法相比 ,增加的工作量不多但更符合工程实际