Uplink Power Saving Potential of Cellular System with Fixed Relays

This paper presented a scheme of relayed cellular mobile telecommunication network, which only employs fixed digital relays and not more than two-hop relay routes. Power saving potential of the network is deeply studied under the assumption of not occupying additional frequency bands （i. e. relays share the same frequency bands as used by the base stations）. Theoretical analysis and simulation results have both shown that, with the same radio coverage requirement, the necessary effective transmission powers in such a relayed network have greatly decreased compared to conventional cellular network.     

一种汽车追尾事故的模糊综合评价

为克服基于大量统计资料的汽车追尾事故评价方法存在的多种因素随机性,提出了一种追尾事故的模糊综合评价方法。以人、车、路为影响追尾事故的主要因素,建立了追尾事故的多级模糊评价模型。在案例分析中以天气指标的变化为算例,证实评价结果会随条件的变化而发生相应的改变,从而说明多级模糊评价模型的可靠性。     

基于元胞自动机的城市道路偶发性拥堵交通行为模拟

以元胞自动机模型为基础,在传统的车辆换道规则上,引入驾驶人行为因素,根据不同区域交通流特点和驾驶行为特点,给出了不同的车辆换道规则,建立了一种适用于城市道路偶发性拥堵交通流行为分析的元胞自动机改进模型。并利用该模型,模拟分析了偶发性拥堵发生时不同车流密度的车辆排队和平均车速情况。     

一种基于信息融合的跟随驾驶行为协同仿真模型

基于信息融合技术模拟驾驶人信息感知、分析决策和车辆控制的全过程,建立跟随驾驶协同仿真模型.模型以动态交通信息为输入,设计单个神经元仿真驾驶人对感知信息的筛选,采用模糊径向基高斯神经网络提取驾驶行为特征向量,应用模糊积分法模拟驾驶人对信息的分析和决策过程,输出为车辆控制状态.离线检验结果表明,该模型能较好地描述跟随车状态变化,具有较高的精度.     

Interference and Spectral Cellular Network with Efficiency Analysis in Two-hop Fixed Relays in FDD Mode

This paper presented ascheme of two-hop cellular network with fixed relay nodes （FRN）. Based on this scheme, co-channel interference and signal interference ratio（SIR） received by base station（BS） and FRN were analyzed. Both the theoretical analysis and simulation results show that the SIR can be improved significantly when relays are employed in the network. The higher spectral efficiency can be obtained due to the improved two-hop link quality through the use of adaptive modulation and coding （AMC）. The antenna height of FRN and the cell radius of BS and that of FRN influence SIR received by BS and FRN and the system spectral efficiency greatly. The proper antenna height of FRN and cell radius of BS and that of FRN were also given to get the highest spectral efficiency.     

控制动作响应延迟下的汽车追尾风险评估

以驾驶人认知响应不及时引发的追尾事故为研究对象,研究驾驶人车辆控制动作响应延迟对追尾事故的影响.定义了汽车驾驶人不响应概率函数,利用反应时间序列进行了求解,绘制了响应时间曲线.采用ANFIS理论,以前后车速差、后车车速、车间距及驾驶人不响应概率为输入,以汽车追尾概率为输出,建立追尾风险评估模型来预测汽车追尾可能性大小.实例分析表明,利用该模型预测汽车追尾风险大小是可行的.     

船舶电机全生命周期数据管理及故障预警研究

为确保船舶安全可靠航运,建立了一种大型船舶电机全生命周期数据管理及故障预警系统.该系统通过输入船舶电机生产制造工艺流程数据和接收设备运行维护数据,可以实现对船舶电机设计制造、运行状态监测、维修服务等全过程进行数据管理,从而有效实现船舶电机运行状态监测、故障及其前兆诊断分析、远程辅助现场维修等功能.     

基于自适应BP神经网络的城市道路偶发性拥堵判别

在分析交通拥堵时空分布特征的基础上,将交通流状态划分为正常状态、常发性拥堵和偶发性拥堵3种;以BP神经网络为基本工具,引入粒子群算法确定网络结构,通过加栽学习动量项加快网络收敛速度,实现偶发性拥堵的准确、快速识别。研究表明,自适应BP神经网络比传统网络在偶发性拥堵判别方面具有更高的正确率,能实现快速判别。     

Interference and Spectral Efficiency Analysis in Two-hop Cellular Network with Fixed Relays in FDD Mode

IntroductionRelaying is well known for its potential of ex-tending the high data rate coverage of a single basestation and reducing infrastructure deploymentcosts. Moreover, it is efficient in solving the cov-erage problem behind the obstacles and eliminatingblack spots, which even can not be solved by intro-ducing smart antenna technology[1,2]. Some dumbrelays (analog repeaters) have been adopted[1]in2 G and 3 G systems. But in such scenarios, thesignals received are forwarded without any si…