交通事件判别是高速公路事件管理系统的重要组成部分,提高事件判别算法性能可以显著改善事件管理系统的运行效果.文中阐述了国内外交通事件自动判别方法的研究现状,分析了以往基于固定式检测器的事件判别算法之不足,如检测速度较慢、低...交通事件判别是高速公路事件管理系统的重要组成部分,提高事件判别算法性能可以显著改善事件管理系统的运行效果.文中阐述了国内外交通事件自动判别方法的研究现状,分析了以往基于固定式检测器的事件判别算法之不足,如检测速度较慢、低流量情况下检测效果较差、可移植性不强等.根据交通事件会显著影响车辆运行速度这一特点,提出了一种基于浮动车数据的交通事件自动判别算法.仿真结果表明,算法具有较高的事件判别率(92.5%)、较低的误判率(1.2%)和较短的事件判别时间(1.6 m in).展开更多
Using a successive method, PAMAM dendrimer-encapsulated bimetallic PdPt nanoparticles have been successfully prepared with core-shell structures (Pd@Pt DENs). Evidenced by UV-vis spectra, high resolution trans- miss...Using a successive method, PAMAM dendrimer-encapsulated bimetallic PdPt nanoparticles have been successfully prepared with core-shell structures (Pd@Pt DENs). Evidenced by UV-vis spectra, high resolution trans- mission electron microscopy, and X-ray energy dispersive spectroscopy (EDS), the obtained Pd@Pt DENs are monodispersed and located inside the cavity of dendrimers, and they show a different structure from monometallic Pt or Pd and alloy PdPt DENs. The core-shell structure of Pd@Pt DENs is further confirmed by infrared measure- ments with carbon monoxide (IR-CO) probe. In order to prepare Pd@Pt DENs, a required Pd/Pt ratio of 1 : 2 is de- termined for the Pt shell to cover the Pd core completely. Finally, a mechanism for the formation of Pd@Pt DENs is proposed.展开更多
文摘交通事件判别是高速公路事件管理系统的重要组成部分,提高事件判别算法性能可以显著改善事件管理系统的运行效果.文中阐述了国内外交通事件自动判别方法的研究现状,分析了以往基于固定式检测器的事件判别算法之不足,如检测速度较慢、低流量情况下检测效果较差、可移植性不强等.根据交通事件会显著影响车辆运行速度这一特点,提出了一种基于浮动车数据的交通事件自动判别算法.仿真结果表明,算法具有较高的事件判别率(92.5%)、较低的误判率(1.2%)和较短的事件判别时间(1.6 m in).
文摘Using a successive method, PAMAM dendrimer-encapsulated bimetallic PdPt nanoparticles have been successfully prepared with core-shell structures (Pd@Pt DENs). Evidenced by UV-vis spectra, high resolution trans- mission electron microscopy, and X-ray energy dispersive spectroscopy (EDS), the obtained Pd@Pt DENs are monodispersed and located inside the cavity of dendrimers, and they show a different structure from monometallic Pt or Pd and alloy PdPt DENs. The core-shell structure of Pd@Pt DENs is further confirmed by infrared measure- ments with carbon monoxide (IR-CO) probe. In order to prepare Pd@Pt DENs, a required Pd/Pt ratio of 1 : 2 is de- termined for the Pt shell to cover the Pd core completely. Finally, a mechanism for the formation of Pd@Pt DENs is proposed.