Evaluating parking reservation policy in urban areas: An environmental perspective

This paper investigates a parking reservation mechanism to reduce car cruising to find parking. To consider the benefits for drivers and parking facility providers, we charge drivers for making reservations in addition to parking fees, by introducing a reservation pricing model that makes reservation prices equivalent to the value of saved search time. By modeling the number of vacant spaces as a stochastic variable, and applying binomial pricing methods, parking reservation prices are obtained. Numerical examples based on the data for two parking facilities in Taiwan are given.     

基坑开挖引起旁侧运营隧道三维变形特性研究北大核心

针对基坑开挖对旁侧隧道的影响问题,建立考虑土体小应变刚度特性的三维有限元数值模型,系统研究了软黏土地层基坑-隧道相互作用机理,分析了隧道埋深和隧道与基坑水平间距对隧道三维变形的影响规律。结果表明:新建基坑在运营隧道旁侧施工时,隧道拱顶和基坑侧拱腰的变形最大;当隧道埋深与直径之比从0.5增至2.5时,隧道的最大竖向位移和最大水平位移降幅分别为69%和34%;当隧道与基坑水平间距与直径之比从0.5增至2.5时,隧道的最大竖向位移和最大水平位移降幅分别为46%和21%;基坑施工时应选择合适的避让距离,降低新建基坑施工对运营隧道的不利影响。     

教育部基金管理信息系统的设计与开发

作者介绍了教育部基金管理信息系统的研究与设计方法,阐述了系统的功能和特点,探讨了数据兼容,对时间的处理以及报表打印的关键技术问题.并针对该系统最关键的评审部分提出了进一步的设想,既用基于WEB的知识挖掘的思想,知识挖掘与网络技术相结合来选择各学科领域的专家建立评审专家库     

Timing rules for major transportation investments

The timing decision for major transportation investments – when to build – typically is made without an objective approach for considering the economic value of implementation at different times. This paper uses a model of benefit-cost analysis and derives rules for timing major transportation investments. Three sets of conditions are considered, depending on whether annual benefits of an investment are uncertain and whether the objective is to maximize net present value or simply to achieve positive net present value. The timing rules under each set of conditions are stated in three forms: benefit-cost ratio, annual benefits, and implementation time. The paper compares these timing rules analytically, discusses potential applications, and illustrates them with a numerical example. Consequences of incorrectly using the timing rules are also examined with the example. This revised version was published online in June 2006 with corrections to the Cover Date.     

风景名胜区景观价值评价理论(Ⅲ):应用

以重庆市金佛山风景名胜区为研究区域,应用风景名胜区景观价值评价体系、基于层次分析法和景观综合评价指数法相结合的风景名胜区景观价值评价方法,以自然景观价值、名胜古迹价值、特色建筑价值、民俗风物价值4个准则层为基础,分别选取相应的25个一级指标、77个二级指标,对金佛山景区景观资源进行综合评价.根据层次分析法,结合最大隶属...     

DV-HOP定位算法改进研究

节点定位是无线传感器网络中的关键技术之一．基于无线传感器网络中DV-HOP定位算法分析的基础上,提出了一种改进算法．该算法通过RSSI测距技术测量点到点的距离,并在多跳网络中对累加距离进行广播,最后在节点位置估计过程中引入了加权质心算法进行定位．实验结果表明,改进后算法复杂度低,定位精度有明显的提高．     

利用AM解析法实现不规则波的入反射分离

基于分离规则合成波的解析方法,提出了不规则合成波分离的理论技术,将不规则波浪等价为特定频率规则波进行分离,首先通过数值模拟方法检验,分离叠加30%噪声的模拟合成波浪,分离精度利用相关系数评价达0.97,然后测试无反射造波水槽中的现场合成波浪,经波谱分析,分离精度能够达到工程标准。     

Maneuvers of motorcycles in queues at signalized intersections

The maneuvering models of motorcycles in previous studies often considered motorcycles' traveling in terms of movements in a physical static lane and not in terms of dynamic virtual lane‐based movements. For that reason, these models are not able to imitate motorcyclists' behavior well. This paper proposes a maneuverability model framework for motorcycles in queues at signalized intersections with considering the dynamic motorcycle's lane. The model includes (i) a dynamic motorcycle's lane to identify the current, left, and right lanes of the subject motorcycle, (ii) a threshold distance to determine when a motorcyclist starts to consider maneuvering, (iii) a lane selection model to identify the lane preferred by a motorcyclist, and (iv) a gap acceptance model to describe whether or not the lead and lag gaps are acceptable for maneuvering. The model framework captures the variation across the motorcyclist population and over time observations. The models were applied to Hanoi and Hochiminh city, Vietnam, based on microscopic data collected from video images. All of the parameters were estimated using the maximum likelihood method with the statistical estimation software GAUSS. The results show that 77.88% of the observed maneuvers – either staying in the current lane or turning left or right – could be modeled correctly by the proposed models. Copyright © 2010 John Wiley & Sons, Ltd.     

上海轨道交通网络运营设备维护管理系统设计概述

从上海轨道交通全网络安全运营的实际需求出发,概述了网络化运营情况下设备维护管理系统的功能特点,详细分析和探讨了从城市轨道交通设备维护系统的应用及网络和软件架构的设计特点。