基于TOPSIS法的自行车停车场布局应用研究——南京鼓楼地铁站实例分析

现代交通设施布局选址过程中,越来越多的面临着多属性多方案优先级排序、在多备选方案中选取最优方案等问题。本文将多目标决策分析法-TOPSIS法应用到自行车停车场布局选址研究中,采用熵权系数法进行决策指标权重的计算,避免了传统方法中主观性强等弊端;并且针对南京鼓楼地铁站确定合理的自行车停车场选址决策指标,基于TOPSIs法完成鼓楼站自行车停车场选址的理论研究;最后通过对鼓楼地铁站的实地调研,进行了详尽分析,对理论上获得的自行车停车场选址结果进行分析检验,验证了该方法的有效性和实用性。     

基于TOD模式的中小城市公共交通规划

为预防中小城市发展过程中出现严重的交通问题,实现城市交通发展与土地利用之间的和谐互动,借鉴国外成功TOD模式的经验,结合我国中小城市特点,分析了中小城市应用TOD模式的需求性与适用性;提出了包含公交路网规划和公交枢纽规划的公共交通规划模式;设计了TOD模式下中小城市公共交通规划流程,包括交通调查与分析、交通需求预测、规划方案制定与调整、方案分析与评价和方案实施。研究结果表明改进的TOD模式将有效引导我国中小城市土地利用,促进城市可持续发展。     

世博交通决策支持信息服务系统研究

根据世博交通保障策略的要求,为确保世博会交通管理有效运行,对世博交通决策支持信息服务系统进行研究。首先介绍了这一系统的技术框架结构,分别阐述了数据层、技术层、应用层、服务层的主要内容。进而对系统功能进行设计,提出世博交通保障措施查询、世博出行方案查询、世博交通运行状况统计、世博交通服务水平评估和客流预测预报5个方面的功能及其具体内容。最后,探讨了系统开发涉及的关键性技术,并对系统开发和实施提出建议。     

基于支持向量机和模糊评判的故障诊断方法研究

将采集到的数据进行模糊化处理,然后运用支持向量机对计算出的模糊样本进行训练,并对其进行模拟仿真,结果与实际试验结果基本相符.克服了根据单一的频谱变化来判断故障的类型,有效地提高了故障诊断性能.     

一种新的基于自组织映射的流形学习算法

针对自组织映射（Self-Organizing Map,SOM）算法在进行流形学习时容易陷入局部极值和产生“拓扑缺陷”问题的原因,提出了一种新的基于SOM的流形学习算法：TO-SOM（Training Orderly-SOM）．根据流形的局部欧氏性,TO-SOM算法从一个局部线性或近似线性的数据子集出发,按照数据的内在流形结构对其进行有序训练,可以避免局部极值、克服“拓扑缺陷”．根据SOM算法的鲁棒性,TO-SOM算法在成功学习数据内在流形结构的同时,对邻域大小参数和噪声也不像ISOMAP和LLE等现有流形学习算法那样敏感,从而更容易得到实际应用．     

基于转移和频率特征的协议异常检测

协议异常检测是目前入侵检测领域研究的新方向．本文研究状态的转移特性和频率特性,在此基础上建立模型进行协议异常检测．模型的训练和检测使用DARPA 1999年的数据集,实验结果验证了所建立模型的准确性．     

FPGA软件无线电平台实现OFDM关键问题的研究

在软件无线电平台上快速实现原型样机,已成为评价通信新技术的重要方法．本文以基于FPGA的软件无线电平台实现OFDM收发信机为例,分析了浮点数与定点数仿真的基本方法及原型样机的设计流程,针对802．11a突发分组OFDM收发信机中的帧同步、符号定时和信道估计等在FPGA中的实现问题,提出了适合于硬件实现的优化算法,节省了硬件资源．最后,在验证平台上实现了全数字OFDM收发信机．测试结果表明,新方法设计合理,收发信机在中频能稳定的无误帧传输．     

Switching between antenna subset selection and quasi-orthogonal space-time block code in presence of correlation

We address the problem of adaptive modulation and coding scheme (AMCS) for a multi-input multioutput (MIMO) system in presence of time-varying transmitting correlation. Antenna subset selection and quasiorthogonal space-time block code (QOSTBC) have different error performances with different signal-to-noise ratios (SNRs) and in different spatial correlation scenarios. The error performance can be improved by selecting an appropriate transmission scheme to adapt to various channel conditions. The maximum distance criterion is the simplest and very effective algorithm for the antenna subset selection without needs of complex calculation and channel state information at transmitter (CSIT). The minimum error performance criteria and the simplified linear decision strategy are developed for constant transmission rate traffic to select the optimal transmission scheme. It can dramatically decrease algorithm complexity for obtaining error probability according to the known quantities comparing with using instant CSIT. Simulation results show that, remarkable performances including low SNR and weak spatial correlation at the expense of simple calculation and almost no bandwidth loss by adopting AMCS can be achieved. The proposed AMCS improves robustness of slowly varying spatial correlated channels.     

Time-varying performance prediction and system identification of internal combustion engines

Design for life-time performance and proper maintenance measures are usually needed to prolong the mean-time-between-failures of complex equipments such as internal combustion engines. To reach this, it is important to obtain the information of time-varying system performance in design stage and to identify the structural change at each moment. So a multidisciplinary model based method is studied in this paper to unify the time-varying performance(TVP) prediction and system identification(SI) of equipments. The related multidisciplinary model in this paper should be not only precise to give simulation results but also sensitive to the variation of system parameters. So the varying history of system performance along with the structural change can be obtained from the model. Then the value of system parameters can be identified by seeking roots with given detected responding data and relationship between system responding data and system parameters. A case study on a low power gasoline engine shows that the method presented in this paper can provide useful information for the development and maintenance of complex equipments.     

ISOFIX固定装置的技术要求及试验方法对比

随着汽车技术的日益发展,儿童乘员数量也在不断地增多,世界上各个汽车制造厂商也对如何保护儿童安全乘车的问题不断地进行技术创新：为适应这种形势,欧美等国家就儿童约束系统出台了相应的法规和标准,并提出了具体的技术要求和试验方法。文章主要介绍了美国和欧洲儿童约束系统标准中有关ISOFIX固定装置的技术要求和试验方法,并结合我国情况,指出随着国家标准的不断完善和企业研发能力的加强,国内儿童乘员保护技术也将取得重大进步。