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1.
The automated fare collection(AFC) system,also known as the transit smart card(SC) system,has gained more and more popularity among transit agencies worldwide.Compared with the conventional manual fare collection system,an AFC system has its inherent advantages in low labor cost and high efficiency for fare collection and transaction data archival.Although it is possible to collect highly valuable data from transit SC transactions,substantial efforts and methodologies are needed for extracting such data because most AFC systems are not initially designed for data collection.This is true especially for the Beijing AFC system,where a passenger’s boarding stop(origin) on a flat-rate bus is not recorded on the check-in scan.To extract passengers’ origin data from recorded SC transaction information,a Markov chain based Bayesian decision tree algorithm is developed in this study.Using the time invariance property of the Markov chain,the algorithm is further optimized and simplified to have a linear computational complexity.This algorithm is verified with transit vehicles equipped with global positioning system(GPS) data loggers.Our verification results demonstrated that the proposed algorithm is effective in extracting transit passengers’ origin information from SC transactions with a relatively high accuracy.Such transit origin data are highly valuable for transit system planning and route optimization. 相似文献
2.
The automated fare collection (AFC) system,also known as the transit smart card (SC) system,has gained more and more popularity among transit agencies worldwide.Compared with the conventional manual fa... 相似文献
3.
城市轨道交通自动售检票车站管理系统在轨道交通运营中直接面向乘客,并在线路自动售检票系统中承担着承上启下的关键作用。从车站管理系统的功能需求出发,结合自动售检票系统具有分层系统的结构特征,对车站管理系统的构架模式和参考模型进行研究和设计,提出关于XML规范接口协议简约与重构的技术思路,描述异构平台数据收发的处理流程,并给出基于WPF技术编程实现设备运营监控界面示例。 相似文献
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3种不锈钢多辊冷轧机的使用比较 总被引:2,自引:0,他引:2
根据使用经验,从机械设备维护、厚度控制和板形控制三个方面对三种不同类型的不锈钢多辊冷轧机进行了比较,指出设计和使用上的不足之处,并给出了一些改进建议。 相似文献
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提出利用层次分析法解决开天窗中部槽天窗选型问题。给出了开天窗中部槽天窗的结构型式及其优缺点,选取"本安性、实用性、可靠性、便利度、工艺性"作为选用开天窗型式的准则,根据层次分析法建立层次结构模型,该模型通过了层次单排序和层次总排序的一致性检验,并得出了科学合理的结论。 相似文献
8.
A wideband fractional-N frequency synthesizer is implemented in a 65 nm CMOS process.It employs a wideband LC voltage-controlled oscillator(VCO) with optimized VCO gain(KVCO/and a sub-band step to improve automatic frequency calibration(AFC) efficiency at negligible expense of phase noise performance.An agile AFC is realized by direct mapping based on the division ratio,and optional redundant counting and comparing calibration is introduced accommodating PVT variations,which samples the reference clock using the prescaled VCO output as a discriminating clock.A charge pump with switched charging current is adopted to compensate for the loop bandwidth variation.Measurement results show this directly-mapped AFC locates the target sub-band in 100 ns and only needs 1.2 s for redundant calibration.The frequency synthesizer spans a frequency range from 0.62 to 1.52 GHz,with phase noise of-86 dBc/Hz at 10 kHz offset and-122 dBc/Hz at 1 MHz offset while consuming 9.76 mA from a 1.2 V supply. 相似文献
9.
The paper presents two types of a passive safety containment for a near future BWR. They are named Mark S and Mark X containment. One of their common merits is very low peak pressure at severe accidents without venting the containment atmosphere to the environment. The PCV pressure can be moderated within the design pressure. Another merit is the capability to submerge the PCV and the RPV above the core level. The third merit is robustness against external events such as a large commercial airplane crash. Both the containments have a passive cooling core catcher that has radial cooling channels. The Mark S containment is made of reinforced concrete and applicable to a large power BWR up to 1830 MWe. The Mark X containment has the steel secondary containment and can be cooled by natural circulation of outside air. It can accommodate a medium power BWR up to 1380 MWe. In both cases the plants have active and passive safety systems constituting in-depth hybrid safety (IDHS). The IDHS provides not only hardware diversity between active and passive safety systems but also more importantly diversity of the ultimate heat sinks between the atmosphere and the sea water. Although the plant concept discussed in the paper uses well-established technology, plant performance including economy is innovatively and evolutionally improved. Nothing is new in the hardware but everything is new in the performance. 相似文献
10.
Aeroelastic performances of smart composite plates under aerodynamic loads are investigated in hygro-thermal environment. The active fiber composite (AFC) which is more effective and adaptive than conventional monolithic piezoelectric material is used in the present analysis to control the undesirable response due to hygrothermal effect. In the presence of hygrothermal load the composite structure becomes weak. But the structure can regain its stiffness in hygro-thermal environment when the AFC layer is activated with the help of applied voltage. The AFC is also effective to enhance the flutter boundary of present aeroelastic structure in hygro-thermal environment. 相似文献