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181.
The paper proposes a multi-class control scheme for freeway traffic networks. This control scheme combines two control strategies, i.e. ramp metering and route guidance, in order to reduce the total time spent and the total emissions in a balanced way. In particular, the ramp metering and route guidance controllers are feedback predictive controllers, i.e. they compute the control actions not only on the basis of the measured system state, but also on the basis of the prediction of the system evolution, in terms of traffic conditions and traffic emissions. Another important feature of the controllers is that they have a multi-class nature: different classes of vehicles are considered and specific control actions are computed for each class. Since the controllers are based on a set of parameters that need to be tuned, the overall control framework also includes a module to properly determine the gains of the controllers. The simulation analysis reported in the paper shows the effectiveness of the proposed control framework and, in particular, the possibility of implementing control policies that are specific for each vehicle type. 相似文献
182.
Yajing ZHENG Xingchen ZHANG Bin XU Linli WANG 《Journal of Transportation Systems Engineering and Information Technology》2011,11(4):16-21
The railway network carrying reliability refers to the carrying capacity meeting the OD demand which consciously changed with random and irresistible factors under prescribed conditions and stated time. Based on reviewing the domestic and international achievement of carrying capacity reliability research and analyzing the characteristics of railway transportation, the paper presents the definition of the carrying capacity reliability of railway network. Then, a model for railway network capacity calculation is developed and the approach for reliability determination is proposed. In the final section, a numerical experiment is conducted with different levels of OD demand. The result shows that the fluctuation of OD demand directly affects the carrying capacity of railway networks, and the effective control of fluctuation plays a positive role for a good performance of railway networks. 相似文献
183.
多层反馈混沌神经网络及其在交叉口优化控制中的应用 总被引:1,自引:0,他引:1
研究城市交叉口交通控制信号优化配时问题。以Hopfield网络和混沌模型为基础,开发了多层反馈混沌神经网络,将其应用于城市交通控制信号配时优化,并开发了应用于优化计算的能量函数和车辆平均延误计算式;探讨了城市交通系统的混沌特性,并开发混沌定量判别算法。以广东某交叉路口为对象进行了仿真,结果表明:与传统的配时方法相比,采用所开发的多层反馈混沌神经网络进行优化配时,交叉路口车辆的平均延误可以平均减少25.1%,可以大大提高路口的通行效率。该网络也可以应用于其他对象的优化。 相似文献
184.
基于神经网络的部分预应力混凝土梁荷载-裂缝模型研究 总被引:3,自引:0,他引:3
混凝土结构裂缝形成和发展的过程十分复杂,具有一定的随机性,难于用常规的方法进行建模。应用神经网络较强的函数映射能力和联想、记忆功能,对部分预应力混凝土梁的荷载-裂缝关系进行建模,通过试验数据进行验证,效果良好,证明应用神经网络来对部分预应力混凝土梁的荷载-裂缝关系进行建模是可行的。 相似文献
185.
研究了求解优化问题全局解的随机神经网络方法,将Gauss模型拓展为广义Gauss模型,使之能求解一般优化问题的全局解。进而引入全局性较好的模拟退火算法的思想,提出了广义Gauss模型的模拟退火算法。通过算例比较了几种计算智能算法的全局性。广义Gauss模型的模拟退火运行全局性最好,但它付出了时间的代价;广义Gauss模型兼顾了计算效率和全局性;广义Hopfield网络的全局性最不理想。 相似文献
186.
IntroductionThe interaction between wireless and wired net-works is becoming important with the growth ofdeployment of wireless networks. Gopal andRaychaudhuri[1]investigated the TCP simultaneous-send problem in infrastructure mode 802.11 wirelesslocal ar… 相似文献
187.
就专网中的星形数据网推导出数学排队模型,并进行计算机仿真,得到相应的网络性能参数,对星形数据网的运行具有指导性意义。 相似文献
188.
189.
本文提出了适应于DWY系列远动系统远动网络五层协议的概念,着重
分析了第三层POLLING通讯方式及其程序实现,并对其实时性进行了
计算,给出了最大响应时间。 相似文献
190.
Zhong-Ren Peng Ruihong Huang 《Transportation Research Part C: Emerging Technologies》2000,8(1-6):409-425
This article presents a Web-based transit information system design that uses Internet Geographic Information Systems (GIS) technologies to integrate Web serving, GIS processing, network analysis and database management. A path finding algorithm for transit network is proposed to handle the special characteristics of transit networks, e.g., time-dependent services, common bus lines on the same street, and non-symmetric routing with respect to an origin/destination pair. The algorithm takes into account the overall level of services and service schedule on a route to determine the shortest path and transfer points. A framework is created to categorize the development of transit information systems on the basis of content and functionality, from simple static schedule display to more sophisticated real time transit information systems. A unique feature of the reported Web-based transit information system is the Internet-GIS based system with an interactive map interface. This enables the user to interact with information on transit routes, schedules, and trip itinerary planning. Some map rendering, querying, and network analysis functions are also provided. 相似文献