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281.
282.
国防交通铁路工程保障指挥决策专家系统的设计与实现 总被引:4,自引:0,他引:4
国防交通铁路工程保障指挥决策专家系统的一个重要部分就是桥梁,隧道,枢纽,线路的抢修方案的决策,本文讨论这四个决策子系统的知识表示与推理机制,每个决策子系统都由破坏情况报告生成部分和推理部分组成,在所有四个子系统听各个部分,均采用统一的面向对象的知识表示方法,从而提高了系统的可维护性和可扩充性,并为基子规则的推理,基于约束的推理,基于数据库的查询和数值计算等多种问题求解机制提供了一个统一的环境,本文 相似文献
283.
通过对通辽站站场边界噪声测量以及对测量结果的分析,初步了解了铁路客运站站场边界噪声污染规律:垂直断面噪声分布是一条外凸曲线;水平面噪声分布呈驼峰状;在噪声组成上,鸣笛噪声占相当大比重. 相似文献
284.
285.
车辆液力减速制动器设计和试验研究 总被引:5,自引:0,他引:5
研究了液力减速制动器循环圆腔室内油液流动的内特性,建立了用于内特性计算的数学模型;对液力减速器空气鼓风损失进行了研究。在此基础上,设计出采用新的减损结构措施的液力减速制动器样机。并进行了相应的台架试验。结果表明,液力制动力矩的理论设计值与试验值接近;减小液力减速器空转鼓风损失的结构措施具有理想的效果。 相似文献
286.
介绍了防抱制动计算机控制仿真系统的设计,从硬件、软件和电液控制方面对系统的构成及设计作了详细的描述。该计算机控制仿真系统除可对车轮制动过程进行实时测控、采样数据进行分析处理和结果显示外,特别是可方便地改变防抱制动系统的控制方法,以分析比较不同控制方法防抱制动系统的控制效能,为实际ABS的设计提供依据。文中给出了应用实例。 相似文献
287.
轮胎非稳态转向特性非线性仿真模型 总被引:2,自引:1,他引:2
本文以轮与路面之间的滑移速度为出发点,在稳态指数统一模型的基础上,建立了轮胎非稳态转向特性非线性仿真模型。在实验研究中,发现了动态过程回正力臂和附加的回正力矩的滞后特性。仿真和试验结果对比表明,该模型足以反映轮胎非线性转向特性,可用于前轮及汽车操纵动力学仿真方面的研究。 相似文献
288.
W. H. Elmaraghy Faculty of Engineering Science 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1987,16(4):193-211
This paper describes mathematical and computer models for ride quality and dynamics of rail vehicles developed for running on personal computers. The purpose of the computer simulations is for prediction of ride quality in order to study the dynamic stability of the system and the effect of track quality and irregularities on ride quality.
In deriving the equations of motion for dynamic stability, the tangential forces acting on the contact areas between the wheels and rails are of fundamental importance in railway vehicles dynamics and are included in the analysis [1]. These forces are due to the creep phenomenon between the wheel and the rail on which it is rolling. Track irregularities are defined in terms of four components consisting of gauge, cross level, alignment and vertical surface profile [2]. Relation of allowable track irregularities versus speed is given by the FRA Track Safety Standards. Analytical representation of track irregularities should include both PSD (Power Spectral Density) for CWR (Continuous Welded Rail) as well as discrete inputs from track joints.
In this paper, the rail vehicle suspension analysis and dynamics mathematical and computer models are described. The computer models are written in Fortran 77 and designed to run on personal computer. The paper also discusses programming considerations that must be taken into account when programming for microcomputers under DOS (IBM's Disk Operating System) and MS or RM Fortran Compilers. Most of the considerations are however, valid in general with respect to engineering software development and programming for microcomputers.
Computer graphics is a powerful tool for visualization of the resulting solutions such as the display of the characteristic roots for the eigenvalues solution on a root locus plot and representation of acceleration levels versus the “Reduced Comfort Boundary” limits defined by the International Standards Organization” (ISO 2631-1985). In this paper some examples of these resulting outputs are presented and their significance discussed. 相似文献
In deriving the equations of motion for dynamic stability, the tangential forces acting on the contact areas between the wheels and rails are of fundamental importance in railway vehicles dynamics and are included in the analysis [1]. These forces are due to the creep phenomenon between the wheel and the rail on which it is rolling. Track irregularities are defined in terms of four components consisting of gauge, cross level, alignment and vertical surface profile [2]. Relation of allowable track irregularities versus speed is given by the FRA Track Safety Standards. Analytical representation of track irregularities should include both PSD (Power Spectral Density) for CWR (Continuous Welded Rail) as well as discrete inputs from track joints.
In this paper, the rail vehicle suspension analysis and dynamics mathematical and computer models are described. The computer models are written in Fortran 77 and designed to run on personal computer. The paper also discusses programming considerations that must be taken into account when programming for microcomputers under DOS (IBM's Disk Operating System) and MS or RM Fortran Compilers. Most of the considerations are however, valid in general with respect to engineering software development and programming for microcomputers.
Computer graphics is a powerful tool for visualization of the resulting solutions such as the display of the characteristic roots for the eigenvalues solution on a root locus plot and representation of acceleration levels versus the “Reduced Comfort Boundary” limits defined by the International Standards Organization” (ISO 2631-1985). In this paper some examples of these resulting outputs are presented and their significance discussed. 相似文献
289.
通过焊接和拉伸试验及微观组织分析,研究了焊接参数对高强度301L-HT板搭接非熔透激光焊接接头结构、断裂行为和力学性能的影响.结果表明:激光焊缝的硬度为HV215,δ铁素体比电阻点焊少,热影响区硬度更接近于母材;焊缝几何结构对激光参数敏感,熔深变化的规律性更明显,特定部位的熔宽与焊接参数耦合有关;板材厚度相同的焊接接头变形刚度接近,焊缝的几何结构决定最后的变形和断裂行为,焊接内板的弯曲变形角度比外板大,两板的弯曲角度差随熔深增加而减小;焊接板弯曲角度和焊接强度随焊缝尺寸同步升高;焊缝硬度低于母材和热影响区导致拉伸变形集中在很窄的区域,焊接接头的断裂位移都小于2mm. 相似文献
290.