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1.
This article presents a summary of the analyses and set of recommendations given by a committee of transit specialists gathered by the Minister of Transport of Chile aiming at improving Transantiago, the new transit system recently inaugurated for Santiago. This summary focuses on those recommendations directed towards improving the efficiency, service quality and sustainability of mass public transportation systems in major cities in the developing world and that could be implemented in a short term (within two years). Three broad dimensions of public transit are considered: competition and regulation; investment, financing, fares and subsidies; and the operation and use of infrastructure, design, inspection and control. Although the study grew out of the needs and characteristics of a city such as Santiago (Chile), and of the virtues and deficiencies of Transantiago, much of the analyses and recommendations could be adopted and implemented in the major cities of developed countries in Europe, North America and Asia.  相似文献   

2.
In a regulated bus system operated by private companies, pecuniary incentives can be of primary importance to ensure the quality of the operation and the level of service, especially when there are only a few companies and basically no competition among them. The case of Transantiago, in the capital city of Chile, provides a good example of this. The very ambitious Transantiago project, implemented in 2007 in Santiago, integrated the bus and the subway systems, changing the route structure of the bus services, introducing a common and integrated fare system and electronic payment device, and tendering the operation of approximately 4,600 buses (which by the launch of the system in February 2007 had increased to 5600) to 10 private companies replacing some 4000 small operators which owned 8000 buses. In the beginning, the system faced huge difficulties. Operators' revenue formula basically consisted of a fixed payment, which changed slightly with the actual patronage. This quickly turned out to be a problem, and as technological support became available (several months after the launch), compliance measures were implemented, directly affecting the operators' revenue. The first measure considered the seat/standing places per hour of the buses in operation, for each company, and compared it to the theoretical figure. As a result, buses operating during peak hours increased from 4600 to 5600 in just two months. Subsequent indexes included service frequency and regularity, as well as effective bus-km, aggregated by company first and later by service. This paper shows how the successive implementation of these performance indexes had an impact on the operation of Transantiago in the first years, discusses the difficulties faced to implement them and highlights the importance of technological support to make possible the application of adequate compliance measures.  相似文献   

3.
转子支承系统的刚度对其临界转速的影响   总被引:2,自引:0,他引:2  
影响转子临界转速的因素很多,支承系统的刚度是其中的一个。本文采用有限元法,通过在Ansys软件中建立某微型燃气轮机支承系统的三维有限元模型,分析其静刚度和动刚度值。然后以其透平转子为例,考察支承系统的刚度值对其临界转速的影响。计算结果表明,与仅考虑轴承的刚度相比,同时考虑支承系统刚度的情况下,透平转子的临界转速下降了约40%。  相似文献   

4.
CAN总线在机舱自动化中的应用   总被引:2,自引:2,他引:0  
徐腊梅  何伟 《船海工程》2006,35(3):102-104
概述了现场总线及其在船舶方面的应用,重点介绍了基于CAN总线技术的机舱自动化系统的结构和CAN模块的开发,实践证明,该系统具有广阔的应用前景。  相似文献   

5.
柴油机双脉冲调速器的仿真研究   总被引:10,自引:0,他引:10  
船舶电站频率的稳定性主要取决于柴油机调速系统的转速响应特性,为了提高柴油机调速系统的动态精度。本文采用了双脉冲调速器,建立了柴油机双脉调速系统的数学模型,并对其进行了计算机仿真研究。计算机仿真实验结果表明,双脉冲调速器能够有效地提高调速系统精度和抑制负荷扰动的能力。  相似文献   

6.
介绍了一种基于对角回归神经网络(DRNN)的直接多步自适应预报器的设计方法。由于其有特殊记忆能力组成单元和特殊的组织结构形式,这种预报器可以在线通过对一个动态系统的输入输出样本的学习,自动建立这个动态系统的模型,而无需事先了解该系统的参数。因此,该预报器可以根据系统过去的输入输出样本和当前可以测量到的系统输入,来获得系统未来的输出值。本文首先介绍了这种预报器模型的结构和输出输入的映射关系,然后给出了一个用于系统预测分析的预测器的具体设计过程并给出一些仿真实验结果,介绍了这种预报模型在船舶机舱智能监控系统中的具体应用。  相似文献   

7.
建立基于虚拟仪器开发平台的柴油机振动监测系统,结合功能强大的数据库,通过分析监测结果,有效地对柴油机运行状态及工作性能进行动态监测,并对它的运行状况做出评估、诊断故障和预测趋势,实测表明,该系统对柴油机故障诊断是可靠的、有效的。  相似文献   

8.
The transportation fare system influences the mobility of a region and the life quality of its inhabitants. This study aims to evaluate a region's optimal fare system by using the analytic hierarchy process, based on a survey among transportation experts, divided into three categories: operators, professors/consultants and government officials. The results are presented divided by category and overall, and the performance of the most important relative criteria to establish a fare system is determined. The most important criterion according to all the selected experts was the fare price, with 21.5%. The fare system determined as the best was distance/zone (31.1%) and the worst was a flat fare system (7.2%). In addition, we show the influence of the fare price criterion in each fare system through sensitivity charts and highlight its importance for all three groups of experts to evaluate the fare system.  相似文献   

9.
面向现代海战的需要,世界各国海军都在加大力度,开发研制各型隐身舰船.射频综合系统是实现舰船隐身的必经之路,其中电磁兼容技术是关键技术.描述了舰船射频综合系统的典型布置和结构方式,针对其结构特点,对其电磁兼容特点和干扰形式进行了理论分析,提出了舰船射频综合系统可能出现的电磁兼容问题和相应解决办法,论述了初步的电磁兼容设计和布置方法,为舰船射频综合系统布置的电磁兼容设计与分析提供理论基础.  相似文献   

10.
为了对冷凝器的真空与凝水过冷度进行有效的控制,根据船用冷凝器的结构与工作原理,建立了冷凝器的简化集总参数模型,并设计了冷凝器的真空与凝水过冷度控制系统.运用Matlab/Simulink软件实现了冷凝器的控制系统仿真,并对降负荷工况进行了计算.结果表明,冷凝器的真空与凝水过冷度控制系统能及时地调节循环水的流量,以保证冷凝器的真空维持不变.同时,通过热力除氧来提高凝水温度,可以有效地将凝水过冷度控制在规定的范围内.这对于冷凝器的真空与凝水过冷度控制系统的设计具有一定的指导意义.  相似文献   

11.
装卸工艺设计的合理与否将直接影响系统的作业效率及系统功能的有效发挥.通过对散粮装卸工艺系统及设备的简要介绍,分析设备选型的特点,找出散粮工艺设计的简单规律.  相似文献   

12.
船用柴油发电机组及其调速系统的动、静态仿真   总被引:2,自引:1,他引:1  
根据船用柴油机及其调遣系统运行特性,设计了一套数字—物理混合仿真装置,该装置能较好地模拟船用柴油机及其调速系统动、静态特性,为船舶电站的设计、研制和运行提供了有效的试验手段。  相似文献   

13.
Solid oxide fuel cell (SOFC) has been identified as an effective and clean alternative choice for marine power system. This paper emphasizes on the dynamic modeling of SOFC power system and its performance based upon marine operating circumstance. A SOFC power system model has been provided considering thermodynamic and electrochemical reaction mechanism. Subcomponents of lithium ion battery, power conditioning unit, stack structure and controller are integrated in the model. The dynamic response of the system is identified according to the inertia of its subcomponent and controller. Validation of the whole system simulation at steady state and transit period are presented, concerning the effects of thermo inertia, control strategy and seagoing environment. The simulation results show reasonable accuracy compare with lab test. The models can be used to predict performance of a SOFC power system and identify the system response when part of the component parameter is adjusted.  相似文献   

14.
叶银忠 《船舶工程》2001,(2):52-55,30
该文提出了高度自动化工程系统中的一种针对人员误操作的安全警戒系统方案,鉴于系统方案的关键是实现操作模式及工况状态的自动鉴别,进而提出了基于大量人工知识和经验规则的模糊逻辑的实现方法,经轮 机模拟器系统的仿真实验,表明其可行性和有效性。  相似文献   

15.
刘辉  金涛 《舰船科学技术》2007,29(5):92-95,98
作战舰艇生命力是衡量舰艇作战能力的重要因素,其评估是对复杂系统的研究过程.元胞自动机是一种"自下而上"的动态模拟建摸框架,具有自组织性和模拟复杂系统时空演化过程的能力.从元胞自动机的概念、构成和原理入手,分析和总结了元胞自动机的基本特征,将元胞自动机应用到对作战舰艇的生命力进行评估,很好地解决了作战舰艇生命力的评估问题.  相似文献   

16.
The primary aim of the design of a shipboard electric power system has traditionally been survivability and continuity of the electrical power supply. Survivability relates to the ability of the power system, when damaged by a threat, to support the ship's ability to continue its missions. Power continuity relates to the ability of the power system to reliably provide power to ship systems under normal operations. This paper proposes new metrics for survivability and continuity of service that enable a better definition of power system requirements linked to the operational needs of the ship. For survivability, the threats for which a ship is designed are its design threats, and the required residual capability following damage from a design threat is the design threat outcome. Quality of service serves as a metric of the continuity of the electrical power supply under normal operation. Quality of service is measured in terms of a mean time between service interruption. A service interruption is defined as any interruption in the supply or deviations outside normal bounds of power quality that prevent a load from performing its assigned function.  相似文献   

17.
李天山  卞根发 《机电设备》2007,24(10):30-33
针对船舶柴油机转速传感器性能指标测试必要性和传统测试仪的局限性,引入实用而高效的分布式智能监控系统,发挥集中管理、分散控制优势.AT89C52应用系统作为后位机,完成具体测控任务;工控机作为管理级,对系统作全面监控和管理.实践证明:该系统具有技术先进、功能可靠、实用、安全等特点、从而进一步提高了船舶柴油机工作效率.  相似文献   

18.
飞剪运动控制系统速度与位置参数整定   总被引:1,自引:0,他引:1  
在飞剪运动控制系统中,准确控制剪刃速度和位置特别重要.文中主要阐述了飞剪的工作原理和参数整定,然后简单介绍了该控制系统构成和功能实现,并在其技术改造中加以应用,取得了良好的控制效果.  相似文献   

19.
滑动变压器在非接触电能传输系统中的研究   总被引:1,自引:0,他引:1  
滑动变压器是自动化码头非接触感应电能传输系统的核心部件,可以实现高速货物运输小车的安全供电。根据滑动变压器气隙较长、漏磁较大的结构特点,建立滑动变压器基于耦合电感理论的状态空间数学模型,以及基于通用软件MATLAB/SIMULINK的仿真模型。该模型参数简明,使用方便。对各种补偿拓扑和谐振频率进行对比分析,验证了模型的有效性,同时为系统补偿方案和工作频率的选择了提供可靠依据。  相似文献   

20.
选择上海浦东新区政府“十一五”建设计划中的综合交通信息管理系统作为研究对象,以体系框架作为研究重点,结合子平台和业务系统进行实例设计。首先对国内外、上海市浦西及浦东的交通管理体制、交通信息管理系统的建设现状进行了分析和总结;其次,研究了上海浦东新区政府、公众、智能交通系统(Intelligent Transport System,简称ITS,以下同)以及世博会等对综合交通信息的需求;在此基础上,以功能的实现为中心,构建了本信息系统的逻辑框架,并详细设计了自上而下、结构清晰、职责明确的物理框架;最后选择体系框架第2层次的环保局子平台和第3层次(含基础设施)的外环线浦东段监控系统进行实例设计,并阐明本体系框架的可行性和实用价值。  相似文献   

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