新建银川至西安铁路庆阳至西安段建设方案研究

为了确定银西线庆阳至西安段合理的建设方案,重点研究客货共线方案、客运专线方案和先接西平、部分缓建3个方案。综合考虑项目功能定位、通道走向、地形条件,结合路网运量,建设时序、路网分工、投资规模等多方面因素进行综合分析比较研究,研究结论为:银西线庆阳至西安段应按照客货共线方案一次建成。     

平流层通信在交通运输行业中的应用

平流层通信是指利用位于平流层的高空平台电台代替卫星作为基站的通信。文章基于平流层通信的特点及发展现状,介绍了平流层通信在交通运输行业中的用途,阐述了平流层通信存在的平台搭载、频谱分配、可靠性方面的问题,并提出了相应的解决措施及建议。     

Adaptive sliding control of active suspension systems with uncertain hydraulic actuator dynamics

An adaptive sliding controller is proposed in this article to control the active suspension systems of a quarter-car model with hydraulic actuator. The highly nonlinear actuator dynamics is assumed to have some time-varying uncertainties with unknown bounds. Owing to its time-variant nature, traditional adaptive designs are not feasible. As the variation bounds are not given, the conventional robust controllers cannot be applied either. In this article, we use the function approximation technique to represent the uncertainties with finite combinations of some basis functions, and the Lyapunov method is employed to find update laws for the coefficients of the approximating series. The actuator force can track the desired force generated from the skyhook dynamics with ultimately bounded performance. If a sufficient number of basis functions are used and the approximation error can be ignored, asymptotic convergence performance can be proved. If the bound of the approximation error is available, asymptotic convergence of the output error still can be obtained with some modifications of the proposed control law. Simulation results show that the controller proposed can give significant improvement of ride comfort when compared with the performance of its passive counterpart.     

Logit模型在广深铁路客流分担率估算中的应用

客流分担率估算的常用方法有分担率曲线法和函数模型法,通过比选决定采用函数模型法中的Logit模型。从旅客和社会需求的角度,对传统的Logit模型特征函数求解进行改进;以安全性、快捷性、票价水平、舒适度、开行间隔、方便性、服务水平和环境友好性等8个参数确定运输产品的效用值,代替传统的Logit模型求解特征函数值。在市场调查和参考专家建议的基础上,确定8个参数的效用值,利用改进的Logit模型,计算出在广深间旅客运输市场中铁路的需求分担率为46.7%,公路为53.3%。依据1999—2003年广深间实际客流量的变化情况,计算出铁路对总客运需求的满足率为18.8%,城际铁路对城际旅客运输需求的满足率为72.7%。可见,广深铁路还远远不能满足社会的客运需求。因此,铁路四线建设应该加速,运营组织模式应该改进。     

青藏铁路线路视频监控系统简介

本文介绍青藏铁路格拉段线路视频监控系统的设计方案，重点介绍了线路视频监控系统的功能及其组成。     

探讨TDCS的发展

本文简单回顾了TDCS的发展历程，提出了今后其他信息化系统建设可供参考的建议，探讨了TDCS功能的进一步扩展。     

论统计工作在高校人事管理中的作用

本文首先阐述了统计工作在高校人事管理中的意义,然后剖析了当前高校人事管理工作中统计作用降低的原因,并从提高认识、提高工作人员素质、完善人事统计指标和加强人事统计信息化建设等方面,提出了相关对策和建议。     

Lateral Vehicle Behaviour: Comparison of Subjective/Objective Assessment Using the Choquet Integral

This paper presents an original method for the aggregation of transverse behaviour indicators obtained first from a subjective assessment then from an objective one of different vehicles tested under normal working conditions. The Choquet integral is used with respect to fuzzy measures. The main advantage of this method is to take account of the existing interactions between the indicators: redundancy, complementarity, inde-pendence. When this tool is used for subjective and objective evaluations, the computation methods of the objective indicators can be validated. Moreover, the influence of the human factor in the judgment of vehicle behaviour is easier to understand.     

铂热电阻Pt100桥式温度变送器电路的传递函数

用铂热电阻Pt100测量介质温度,是温度采集和自动控制系统中普遍采用的方式。由于铂热电阻温度传感器在实际应用中存在电阻与温度间的非线性关系,为进一步提高温度测量的准确性,提出一种利用计算机非线性修正技术实现Pt100桥式温度变送器电路传递函数的方法。     

数字电路监督系统功能及维护

结合数字电路监督系统的特点,浅议系统的功能和维护,对提高系统运行的稳定性,解决系统运行中存在的问题,提高维修人员的维护水平有一定的借鉴意义。