Understanding and Modeling the Social Preferences for Riders in Rideshare Matching

Transportation - Ridesharing is the sharing of trip segments from one place to another among multiple travelers, obviating others’ needs to drive themselves. By having more than one occupant...     

Comparison between North-South Aid and South-South Cooperation: Based on the analysis of the new development finance institutions

According to the different players, development cooperation is often divided into North-South Aid and South-South Cooperation, both of which have a history of several decades. Since the beginning of the 21st century, the rise of a number of emerging economies has brought South-South Cooperation into a new stage, which can be seen from the establishment of some new development finance institutions led by developing countries. BRICS Bank, Asia Infrastructure Investment Bank (AIIB) and Silk Road Fund are three important new development finance institutions. Compared with the traditional development finance institutions like World Bank and International Monetary Fund (IMF), they have their own concepts of development cooperation, which are different from the traditional ones. First, the new finance institutions pay more attention to the equality between partners, not imposing conditions and respecting the ownership of development partners. Second, the new development finance institutions value the market philosophy, which means that they emphasize the importance of field investigation and implement development cooperation in accordance with the actual needs of the partners and the comparative advantages of the providers. Finally, the new development finance institutions focus their resources on problem-solving and avoid doctrines-imposing. They believe that it is easier for the developing countries to achieve development through a gradual and bottom-up model. Although there are differences between the traditional and new development finance institutions, the latter is not parallel to or substitute of the former. They can cooperate with each other and provide better public goods for international cooperation through inclusive competition.     

纽约市地下物流可行性研究及对世界其他主要城市的启示

在纽约州能源与发展局的资助下。纽约市最近完成了基于风力舱体管道（以下简称PCP）技术的地下物流技术与经济的可行性研究。主要内容包括6个方面：（1）地下隧道中的原料运送;（2）固体废物运往城外处理和再利用：（3）在纽约和华盛顿特区之间传递邮件和包裹;（4）用板条箱、普通的箱子或袋子运送货物;（5）在海港与内陆的处理或检查站之间运输集装箱：（6）解决位于纽约亨特地区大型食品市场的卡车进出问题。研究发现上述6方面的应用在技术上是可行的,前5个应用在经济上是可行的。以上提到的这些应用在将来不仅可以为纽约带来经济上的繁荣。降低货物运输的成本,还可以降低由于卡车运输带来的大多数问题,如交通堵塞、交通事故、噪声、空气污染和汽车炸弹。文章首先介绍了纽约城市管道货物运输的概况,然后讨论了它对其他城市的启示。城市地下物流的主要问题包括：建设问题、安全性及环境影响等。该文给致力于在城市区域内通过地下管道与地下道路来运送货物的交通规划者提供必要信息。     

Analysis of Responses of Pile Groups Due to Tunnelling during Excavation and Operation Periods Considering Rheological Behavior of Soft Soils北大核心CSCD

The additional pile responses due to the rheological behavior of the soil in the construction and operation periods of tunnelling are disadvantageous to the safety of the pile. However, among the current studies concerning with the rheological behavior of soft soil, the pile responses induced by the long-term settlement of 3D soil are seldom investigated. This paper mainly utilizes the finite difference software FLAC to discuss the pile response during excavation and operation periods considering rheological behavior of soft soil based on twostage analysis method. At the first stage, the displacement controlled method (DCM) is applied to simulate the short-time movement of soil during excavation period, the simulation results such as the shape of trough, pile responses such as pile deflection, settlement, axial force and bending moment are compared with the results of existing studies, and the numerical model is verified to be acceptable. At the second stage, the rheological behavior of soft soil is considered to estimate the long-term settlement of soil, the additional pile response is analyzed based on the CVISC model. Then, the influences of the four rheological mechanical parameters on the long-term soil settlement and pile responses are discussed and a fitting equation is proposed to estimate the long-term settlement of soil during the operation period. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

电力系统网络拓扑方案研究

电力监控系统对网络的实时性要求很高,在网络设计阶段较难开展与拟建网络规模可比的实验来判断网络应用到电力监控系统中的实时性能。电力系统监控网络较复杂,相比建立有效的解析模型对它进行数学分析,网络仿真法更适合大型系统的性能预测,本文采用网络仿真法对电力系统网络从网络时延、可靠性、流量特性进行分析比较,为今后组建电力系统监控网络提供依据。     

基于滑动轴承振动模型的轴频电流建模与仿真

针对舰船轴频电场信号源的发生机理和应用研究的问题,建立了一种轴频电流的等效电路模型。模型基于滑动轴承的涡动现象,采用短轴承理论对轴承运动微分方程进行了求解,获得了轴径轨迹,然后结合电接触理论,建立了滑动轴承电接触电阻模型,对轴频电流的变化趋势进行了仿真,并将仿真结果与实船轴频电流进行了对比,结果表明,所建模型直观简便,轴频电流与实测结果的基波和二次谐波吻合较好。     

基于新型内装材料的公路隧道行车安全研究

驾驶员的眼动特性能很好地表现视觉信息处理过程,可通过驾驶员在高速公路隧道内行驶过程中的眼动特性变化规律来分析公路隧道侧壁采用不同内装材料条件下照明环境所带来的行车安全性和舒适性。文章运用Smart Eye Pro 5.7型非侵入式眼动仪系统,以高速公路隧道驾驶员行驶过程中的眼动特性为评价指标,基于云南宝腾高速公路鹿山隧道工程实例,对三种内装材料下的注视持续时间、注视区域、瞳孔变化及变化速率进行了实车试验,得出了驾驶员在上述3种工况下的眼动特性变化规律。试验结果表明,在同种条件下使用蓄能自发光内装涂料的公路隧道内驾驶员的注视特征明显优于使用其它材料的工况,瞳孔直径变化最小、变化率最平稳,即蓄能自发光涂料能显著提高驾驶员行车进入隧道过程中的安全性和舒适性指标。     

基于差异性区域预测的行人与骑车人联合检测

本文中针对自动驾驶车辆在环境感知过程中易将行人与骑车人混淆的问题,提出一种有效区分行人与骑车人的联合检测方法,并基于快速区域卷积神经网络Faster R-CNN进行改进.首先,通过增加一个子网络提取图像形状特征通道,将其与主干网络生成的特征图进行聚合,额外的形状语义通道用以辅助检测器区分行人与骑车人的特征;接着,通过构...     

区间闭塞技术改造

在原有设备的基础上,通过技术改造,用最经济的办法,将区间原有的半自动闭塞改为自动闭塞,提高了列车的通过能力,提高了运输效率。     

高档客车ABS及ASR制动系统

讲述带有ABS及ASR的高档客车制动系统的结构和工作原理,并举出实例作为介绍。