移动APP测试技术在车辆运行状态检测应用的可行性分析

文章在分析传统车辆运行状态检测技术的原理和方法的基础上,结合移动客户端内置传感器的种类和功能,探究了基于移动客户端APP测试技术检测车辆运行状态的可行性,并依据GPS/INS组合导航方法设计了GPS重调惯导、位置和速度信息组合模式两种检测方案。针对移动客户端采集数据的特征,通过数据有效性检查、采样频率检查与修正、修补丢失数据和数据滤波4个处理环节来消除原始数据中存在的数据无效点、采样点丢失、噪声干扰等缺陷,提高检测数据的可靠度及精度。研究结果表明:利用移动客户端完全可以实现车辆运行状态的检测,从而大大降低了车辆运行状态检测的成本和时间投入。     

Examining the effect of land-use function complementarity on intra-urban spatial interactions using metro smart card records

Transportation - Spatial interaction is an important phenomenon that reflects the human–land relationship and has long been a core topic in multiple fields, such as urban planning,...     

A new method for wheel–rail contact force continuous measurement using instrumented wheelset

With the aim of improving the continuous measurement of wheel–rail contact force by instrumented wheelset, instead of solving the non-linear equations, we proposed a new method based on state space theory. With this new method, the wheel–rail contact force can be calculated by the recurrence relation and the signals from strain gauge bridges on wheel web. The implementation of continuous instrumented wheelset is quite general and simplified, due to the specific bridging scheme is not necessary. It means that continuous measurement of the contact force could be realised with a simple bridging scheme, even as simple as discrete instrumented scheme. In this work, we first demonstrated and discussed the effectiveness and accuracy of this new method by estimation results with the numerical simulations, and we also applied this new method to two field tests, including one was conducted in a loop test line using a high-speed train and the other one was conducted in an urban line with a light rail vehicle. In a word, this new method is proved to be an effective way to monitor the wheel–rail contact force of rail vehicle track system.     

考虑空气力的车辆三自由度转向模型与状态方程

为了减小空气力的影响,简化车辆多自由度转向动力学方程,考虑了空气力的影响,建立了车辆三自度转向运动的动力学模型.以质心侧偏角、横摆角、横摆角速度、侧倾角、侧倾角速度为状态变量,以前轴转角及侧风作用力为输入,以质心侧偏角、横摆角、横摆角速度、侧倾角为输出,推导了车辆三自度转向运动的动力学模型的状态方程.以前轴主动转角脉冲为输入,对状态方程的可信度进行了验证.与利用线性二自由度转向模型的仿真结果相比,利用三自由度转向模型与其状态方程得到车辆质心侧偏角与横摆角速度的绝对值均较小,在高速情况下,空气力会增强车辆的不足转向特性.采用两种模型得到的车身侧向偏移均大于试验值,但三自由度模型的仿真曲线非常接近试验曲线.可见,三自由度状态方程可信度高.     

苏通大桥承台封底混凝土与钢护筒间握裹力的试验研究与应用

通过对苏通大桥承台封底混凝土与钢护筒间握裹力的试验研究与施工现场监测,提出钢护筒与承台封底混凝土间的握裹力系数。     

转辙机可靠性试验加载装置的研制

通过分析转辙机可靠性试验对加载装置的要求，认为液压式加载比机械式加载更适合转辙机的可靠性试验，对液压加载装置的每个元件都采取为保证其有较高的可靠性，以提高整个液压加载装置的可靠性，试验结果表明液压加载系统达到了预期的目的。     

表面噪声矢量场空间相关特性射线声学建模(英文)

Spatial correlation of sound pressure and particle velocity of the surface noise in horizontally stratified media was demonstrated,with directional noise sources uniformly distributed on the ocean surface.In the evaluation of particle velocity,plane wave approximation was applied to each incident ray.Due to the equivalence of the sound source correlation property and its directivity,solutions for the spatial correlation of the field were transformed into the integration of the coherent function generated by a single directional source.As a typical horizontally stratified media,surface noise in a perfect waveguide was investigated.Correlation coefficients given by normal mode and geometric models show satisfactory agreement.Also,the normalized covariance between sound pressure and the vertical component of particle velocity is proportional to acoustic absorption coefficient,while that of the surface noise in semi-infinitely homogeneous space is zero.     

系泊系统非线性恢复力研究及其应用(英文)

Mooring system plays an important role in station keeping of floating offshore structures.Coupled analysis on mooring-buoy interactions has been increasingly studied in recent years.At present,chains and wire ropes are widely used in offshore engineering practice.On the basis of mooring line statics,an explicit formulation of single mooring chain/wire rope stiffness coefficients and mooring stiffness matrix of the mooring system were derived in this article,taking into account the horizontal restoring force,vertical restoring force and their coupling terms.The nonlinearity of mooring stiffness was analyzed,and the influences of various parameters,such as material,displacement,pre-tension and water depth,were investigated.Finally some application cases of the mooring stiffness in hydrodynamic calculation were presented.Data shows that this kind of stiffness can reckon in linear and nonlinear forces of mooring system.Also,the stiffness can be used in hydrodynamic analysis to get the eigenfrequency of slow drift motions.     

基于模糊层次分析法的指挥员决策能力分析

以自行火炮营为例,提出基于模糊层次分析法的指挥员决策能力量化模型,采用多层次模糊综合评判的方法进行综合评价,最终确定自行火炮营指挥能力的优劣性。     

用于直流快速开关的电磁斥力机构仿真及优化设计

本文对用于直流快速开关的电磁斥力机构进行仿真分析研究,通过优化影响电磁斥力机构设计的主要参数设计了试验样机。通过样机的试验,验证了仿真分析的准确性。