基于流行病模型的车路协同预警信息交互方法

针对车辆移动速度快、行驶路径受道路约束、网络拓扑结构易改变的特点,提出了一种基于流行病模型的车路协同安全预警信息交互方法,并采用马尔可夫链对传播延迟进行了理论分析.实验采用NS2网络仿真平台,构建了2 000 m长、20 m宽的双向车道测试场景,移动节点间采用802.11协议,实验测得的延迟结果与理论分析基本一致.      

Latent heat flux and air temperature anomalies along an active fault zone associated with recent Iran earthquakes

Pre-earthquake physical and chemical interactions in the earth’s ground may cause anomalies in latent heat flux, air and surface temperature. Earthquakes occur when the energy accumulated in rocks releases. Sometimes, the movements of the ground cause ruptures in the earth’s surface and sometimes the two sides of an existing fault shift towards each other. In a structurally complex and inhomogeneous collision region such as the Iranian Plateau, seismicity is not the result of activity of a single fault but is due to energy discharge in fault zones hundreds of kilometers wide.     

一种基于时延约束的最优路径求解算法

作为QoS路由和流量工程的关键技术之一,基于时延约束的最优路径问题一直没有得到有效的解决.针对现有的算法很难得到最优解和计算复杂度过大等问题,提出了一种基于时延约束的最优路径求解(DCOP)算法,该算法通过减少算法的搜索空间来有效地降低算法的计算复杂度,可得到最优的无环解.算法采用自适应参数设计,提高了对网络规模和复杂业务变化的适应性.仿真表明该算法比同类算法计算复杂性降低了近一个数量级,且算法具有自适应能力,设计简单,易于工程实现.      

基于DES的单跑道地面等待模型研究

提出了一种新的基于离散事件系统(DES)的单跑道地面等待数学模型.针对 影响机场跑道降落服务时间的不同条件,提出了确定性模型和随机性模型,分别给出了2 个模型的计算方法,比较了算法计算量.并详细研究了跑道降落服务时间参数以及空中等待 和地面等待费用比参数的特性.仿真结果表明算法是行之有效的.该算法已成功应用于空军 某部流量评估系统中.      

空中交通服务电报智能处理系统

空中交通服务电报采用固定的信息编组方式组织报文.由于传输差错及人为因素引起了报文的非标准化,计算机自动处理困难.本文提出了基于模式识别、神经网络技术的报文处理算法,并进行了仿真实验,结果表明该算法具有较高的报文正确识别率,以及维护简单、扩充方便灵活的优点.      

Geomagnetic effects on mid-latitude railways: A statistical study of anomalies in the operation of signaling and train control equipment on the East-Siberian Railway

Intense geomagnetically induced currents (GIC) can hamper rail traffic by disturbing signaling and train control systems. GIC threats have been a concern for technological systems at high-latitude locations due to geomagnetic disturbances driven by substorm expansion electrojet or convection electrojet intensifications. However, other geomagnetic storm processes such as storm sudden commencement (SSC) and geomagnetic pulsations can also cause GIC concerns for technological systems. We present in this paper the first evidence based on statistical data for links between geomagnetic disturbances and faulty operations (anomalies) in the functioning of railway automatics and telemetry. We analyze anomalies of automatic signaling and train control equipment which occurred in 2004 on the East-Siberian Railway (corrected geomagnetic latitude _m = 46–51°N and longitude λ_m = 168–187°E). Our results reveal a seasonal effect in the number of anomalies per train similar to the one observed in geomagnetic activity (Kp, Ap, Dst indices). We also found an increase by a factor of 3 in the total duration of daily anomalies during intense geomagnetic storms (local geomagnetic index specific to Siberian Observatory A_max > 30), with a significant correlation between the daily sum of durations of anomalies with geomagnetic activity. Special attention was paid to failures not related to recognized technical malfunctions. We found that the probability of these failures occurring in geomagnetically disturbed periods was 5–7 times higher than the average anomaly occurrence.     

Cosmic radiation exposure of aircraft occupants on simulated high-latitude flights during solar proton events from 1 January 1986 through 1 January 2008

From 1 January 1986 through 1 January 2008, GOES satellites recorded 170 solar proton events. For 169 of these events, we estimated effective and equivalent dose rates and doses of galactic cosmic radiation (GCR) and solar cosmic radiation (SCR), received by aircraft occupants on simulated high-latitude flights. Dose rate and dose estimates that follow are for altitudes 30, 40, 50, and 60 kft, in that order.     

基于传递闭包法的航班分类模型及在航班排序中的应用

提出了一种基于传递闭包法的进/离场航班分类方法.首先对模糊集合理论和传递闭包算法作了简要的介绍,然后在考虑4种不同因素的条件下建立了航班分类模型,并给出了各类航班单位时间延误成本的计算公式.最后以终端区航班排序模型为例,对该方法进行了仿真,并与传统航班延误成本分类方法进行了比较.仿真结果表明,该方法有助于减少航班延误损失,优化进/离场航班队列,提高空中交通管理效率.     

基于本体的陆空通信风险识别与分析方法

陆空通信是实施空中交 通管制的重要手段,也是民航空管运行中造成不安全事件的重要因素之一。提出针对陆空通信 危险识别与分析的系统参量和引导词,应用BPMN和HAZOP模型识别与分析陆空通信危险偏差 。建立陆空通信风险识别与分析本体模型。构建概念之间的TBox描述逻辑关系和推理,案例 推理证明了方法的有效性。该方法能够实现规范化、术语化风险描述和归类,避免通过自然 语言进行风险识别与分析的缺点,为更有效地进行风险项分析提供科学分类和统计依据。