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高速铁路接触网风致振动与风偏的动态计算方法 总被引:2,自引:1,他引:1
《铁道标准设计通讯》2016,(6):121-126
利用ANSYS软件建立接触网弹链、简链风致响应有限元模型,从导线弛度、张力及弹性角度,验证有限元模型的准确性;采用谐波合成法(WAWS)模拟针对接触网结构特点的脉动风场;计算系统在风荷载作用下的动态响应,利用空气动力学理论计算接触网平均位移,采用时程分析方法计算接触网动态位移,并将二者叠加得到接触网风致响应总位移。通过开展接触网气动弹性风洞试验,结果表明:提出的基于有限元的风致振动与风偏的动态计算方法与风洞试验结果基本吻合;该方法计算结果准确,具有较好的工程应用价值。 相似文献
33.
厢式载货汽车模型风洞试验技术的研究 总被引:1,自引:0,他引:1
风洞试验是进行汽车空气动力学研究的重要手段,介绍了试验数据系统,论述了用小型航空风洞进行厢式载货汽车模型试验时雷诺数,堵塞比,模拟地板等重要技术问题,给出厢式载货汽车改善气动阻力特性的试验结果。 相似文献
34.
摩托车国Ⅲ工况排放测试和耐久性测试中,摩托车要在底盘测功机上跟踪规定的曲线行驶,风机模拟道路行驶中的自然风冷却车辆,速度满足风速等于车速。由于从风机出口断面到摩托车发动机有一定距离,随着距离的增加,出口风速、风量会发生衰减和扩散,这样,到达发动机的风速必然小于车速,致使冷却效果下降,模拟效果不佳,长时间运行还会对发动机、催化转化器产生损害,影响排放结果。 相似文献
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Surface current data from drifting buoys and remotely sensed wind data recorded over the continental shelf in the northeastern Gulf of Mexico during the passage of tropical storm Josephine in October 1996 are examined. Drifter data show the existence of a strong surface jet (velocities reaching 1 m s−1) that moves up the west Florida shelf and westward along the Louisiana–Texas shelf, and lasts for nearly 1 week. The coastal jet occurs during an intense synoptic scale wind event where wind speeds reach 15 m s−1. A simple force balance and statistical analysis are performed to assess the role of strong wind forcing. The primary balance shows an Ekman-type current. The role of local acceleration is greatest when winds are directed along bathymetry. A simple two-dimensional strongly forced shelf response model developed from the linear steady-state momentum equations also indicates larger along-shore currents due to both Ekman-type forcing by cross-shore winds and a cross-shore pressure gradient arising from conservation of mass. Model parameters fit empirically are within 15% of theoretical values. The simple model explains 30% and 46% of the variance in the observed along-shore and cross-shore surface currents, respectively. 相似文献
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轿车外流场的二维数值模拟 总被引:3,自引:1,他引:3
本文采用计算流体动力不方法数值求解N-S方程,模拟了轿车外流场,计算结果与风洞试验结果基本一致。 相似文献
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Masaru Tsujimoto Takashi Uehiro Hiroshi Esaki Takeshi Kinoshita Ken Takagi Susumu Tanaka Hiroshi Yamaguchi Hideo Okamura Masuho Satou Yoshimasa Minami 《Journal of Marine Science and Technology》2009,14(1):89-103
To acquire the wind energy of the oceans, a sailing wind farm has been proposed. The wind farm considered is composed of a
semisubmersible floating structure, 11 windmills, four sails, six thrusters, and storage for hydrogen. To maximize the acquired
energy, an effective algorithm to search for optimum routes was developed. The algorithm is based on the fact that beam winds
yield a maximum of acquired energy. This feature reduces the computation time, and, consequently, efficient route optimization
becomes possible in a reasonable time. After setting an operational area for the wind farm, navigation simulations for a 1-year
period were carried out. A numerical weather forecast was used as well as the responses of the floating structure, such as
the speed of the structure, the output power of the windmills, and the time of course changes. In the simulation, the wind
farm evades rough seas to avoid structural damage, and an optimum route is searched for. The capacity factor of the system
was used to evaluate the efficiency of the optimized routes. From the simulations, the maximum capacity factor achieved was
42.6%. The dependency of the capacity factor on the initial position of the wind farm was also examined. It was shown that
offshore from Sanriku in northeastern Japan is an area suited to the operation of the wind farm. The effect of the initial
position on consecutive periods of operation is discussed. 相似文献