论大学英语合班教学环境与学生自主学习模式的建立

如何解决合班课中存在的问题、保证英语课堂教学效果已成为近年来外语教学界关注的热门话题。文章从教师角色的转变、学习协作性的培养、课堂提问的设计和课下自主学习资源的利用等几个方面探索了如何通过培养学生的自主学习能力来提高教学效果。     

Critical success conditions of collaborative methods: a comparative evaluation of transport planning projects

This paper explores critical success conditions of collaborative planning projects in the area of urban transport, evaluating the impact of new collaborative methods, instruments and processes on project performance. Hypothesis building is based on a comparative, empirical research design, rather than on deductive theory construction. Potential critical success conditions are derived from literature. Based on five urban transport planning projects in Gothenburg (Sweden), London (United Kingdom), Milwaukee (United States), Tokyo (Japan) and Mexico City (Mexico), a rough set analysis of the five cases reveals validated success conditions, which can be used for formulating hypotheses for further research or for policy and process improvement. The results suggest that a dedicated management of the multi-actor network, a high diversity of actors, as well as an extensive use of knowledge integration methods in combination with a high network density are critical success conditions of these planning processes. Surprisingly, the extensive use of unilateral methods also showed to be an important success condition. The traditional role of the planner will have to be complemented with the expertise of network and methodology management. The authors conclude that rough set analysis can be a valuable addition to narrative, single-case analysis of collaborative urban transport planning processes.     

工业控制系统信息安全可靠的解决方案AutoNet分布数据库DCS平台+PPC200万能PLC

信息安全可靠是工业控制系统的灵魂,只是功能开得动而没有信息安全可靠设计的工业控制系统像一贴慢性毒药,会造成工业系统的瘫痪。本文介绍了重点设计信息安全可靠的AutoNet分布数据库DCS系统及PPC200万能PLC的能抵御网络攻击及八项信息安全可靠的解决方案,特别适用于舰船、高铁、核电等高可靠要求的控制系统。     

小型无线传感器网络的实现与WLAN互联

目前无线传感器网络由于其覆盖范围较小,数据处理能力有限的特点,使其应用受到一定限制.而通过无线局域网覆盖多个无线传感器网络,就可以实现多个传感器网络的互联,为用户提供更加灵活,范围更大的信息服务.本文在设计并实现了基于SimpliciTI协议的小型无线传感网络的基础上,将其通过无线局域网覆盖,实现无线传感器网络的无线局域网接入与多个传感器网络的互联,并给出硬件和软件设计方案.     

广域网络环境下交通数据管理方法研究

针对交通数据具有的分布、异构、自治、海量、动态和进化特征，提出了广域网络环境下，基于CORBA＋Agent的交通数据管理方法，把交通数据管理分为局部数据管理和系统级数据管理两个层次。局部数据管理解决数据的自治、海量、动态和进化问题，系统级数据管理解决广域网络环境下的分布和异构问题，从而实现交通数据的无缝连接、透明访问、数据集成和综合服务。实际系统的开发说明此方法可以用于实际交通系统的数据管理中。     

一种新型城市快速路网交通诱导系统的研发和应用

介绍了一种新型的基于可变信息标志(VMS)的网络级城市快速路交通诱导系统的设计方法。该系统是一个由“重要决策点图形式VMS”、“次要节点图文混合式VMS”、以及“地面一般道路VMS”三类VMS组成的VMS系统。文章在归纳VMS系统设计流程基础上,重点介绍了VMS的路网布局和功能设计、显示格式和显示技术的确定、VMS设立位置(前置距离)的确定、图形式VMS的面板设计和交通信息发布策略等关键技术,最后给出系统的应用实例,说明该新型交通诱导系统的应用效果。可供交通管理部门规划、设计城市快速路网交通诱导系统参考。     

A Real-Time Parking Prediction System for Smart Cities

A methodological framework for multiple steps ahead parking availability prediction is presented. Two different types of predictions are provided: the probability of a free space to continue being free in subsequent time intervals, and the short-term parking occupancy prediction in selected regions of an urban road network. The available data come from a wide network of on-street parking sensors in the “smart” city of Santander, Spain. The sensor network is segmented in four different regions, and then survival and neural network models are developed for each region separately. Findings show that the Weibull parametric models best describe the probability of a parking space to continue to be free in the forthcoming time intervals. Moreover, simple genetically optimized multilayer perceptrons accurately predict region parking occupancy rates up to 30 minutes in the future by exploiting 1-minute data. Finally, the real time, Web-based, implementation of the proposed parking prediction availability system is presented.     

Infrastructure-cooperative algorithm for effective intersection collision avoidance

To guarantee the road safety by avoiding collisions at the intersections is one of the major tasks of intelligent transportation systems (ITSs), which contributes to the minimal fatalities and property loss in crashes. This paper proposes an effective algorithm for infrastructure-cooperative intersection accident pre-warning system with the aid of vehicular communications. The proposed algorithm realizes accurate and efficient collision avoidances through five steps, i.e., defining variable, reasoning the vehicles evolution state, verifying safe driving behavior, assessing risk, and making decision. The critical factors are theoretically analyzed, and a vehicle state evolution model based on the Dynamic Bayesian Networks (DBNs) is established. The efficient risk assessment method based on identifying the dangerous driving behavior at intersection and different collision avoidance strategies are proposed according to the actual situation. Finally, extensive simulations are carried out to verify the performance of the proposal, and simulation results show that the proposed algorithm can effectively detect risk and accurately migrate the collision.     

轨道交通高架车站钢结构与混凝土结构协同分析

基于成都轨道交通高架车站钢结构雨棚方案比选和结构设计,围绕高架车站站台钢结构雨棚与下部混凝土结构考虑协同作用对比分析。通过对不同高架车站下部混凝土结构和相同上部钢结构,采用有限元软件MIDAS建立整体和独立模型,对结构分别采用反应谱分析、屈曲分析进行对比计算。找出结构整体模型计算在周期模态、最大层间位移、最大层间位移角、柱底反力、屈曲临界荷载等方面与下部混凝土结构独立计算存在的差异。分析结果表明,高架车站独立模型计算的周期均小于整体模型计算;两种模型的层间位移和柱底反力均存在差异,其中单墩柱整体模型计算不能忽视;整体模型比独立模型计算的屈曲临界荷载值大。     

Airline-driven ground delay programs: A benefits assessment

Three decades of research studies in ground delay program (GDP) decision-making, and air traffic flow management in general, have produced several analytical models and decision support tools to design GDPs with minimum delay costs. Most of these models are centralized, i.e., the central authority almost completely decides the GDP design by optimizing certain centralized objectives. In this paper, we assess the benefits of an airline-driven decentralized approach for designing GDPs. The motivation for an airline-driven approach is the ability to incorporate the inherent differences between airlines when prioritizing, and responding to, different GDP designs. Such differences arise from the airlines’ diverse business objectives and operational characteristics. We develop an integrated platform for simulating flight operations during GDPs, an airline recovery module for mimicking the recovery actions of each individual airline under a GDP, and an algorithm for fast solution of the recovery problems to optimality. While some of the individual analytical components of our framework, model and algorithm share certain similarities with those used by previous researchers, to the best of our knowledge, this paper presents the first comprehensive platform for simulating and optimizing airline operations under a GDP and is the most important technological contribution of this paper. Using this framework, we conduct detailed computational experiments based on actual schedule data at three of the busiest airports in the United States. We choose the recently developed Majority Judgment voting and grading method as our airline-driven decentralized approach for GDP design because of the superior theoretical and practical benefits afforded by this approach as shown by multiple recent studies. The results of our evaluation suggest that adopting this airline-driven approach in designing the GDPs consistently and significantly reduces airport-wide delay costs compared to the state-of-the-research centralized approaches. Moreover, the cost reduction benefits of the resultant airline-driven GDP designs are equitably distributed across different airlines.