铁路客运段信息化综合管理系统

根据我国铁路客运段的现状,集成基于GSM-R的无线移动售/补票子系统、车长办公子系统、餐车管理子系统、列车GPS定位与自动语音播报子系统、列车移动视频监控子系统五大车载系统,构建客运段信息化综合管理系统。在客运段建立集成平台,统一数据接口,规范客运业务,提供WEB查询服务,并对其中的两个关键子系统给出实现方案。铁路客运段信息化综合管理系统已在武汉铁路局下属客运段实际运行,取得了良好效果。     

科技引领生态景观大道建设 创新打造未来城市名片

介绍了天津市滨海新区天津大道"绿色、生态、景观、环保、节能、和谐"的设计主题。从该工程的规划、设计,路基处理,路面材料,边沟设置,景观设计等方面阐述了工程的创新思想,并介绍了该工程绿色生态型城市快速路集成技术、城市快速路生态化设计技术集成、天津滨海新区城市快速路软土地基处理等科研课题的内容。     

考虑流凌效应的大跨径梁桥最大悬臂施工状态作用响应分析

内蒙古包树黄河特大桥工程在黄河凌汛期恰好处于最大悬臂施工阶段,为保证其安全度汛,对此种不利工况进行作用响应分析及安全性验算.采用计算土弹簧刚度来模拟桩-土摩阻效应,并采用Maxwell模型以模拟墩顶新型粘滞阻尼器的墩梁位移效应,建立了该桥最大悬臂施工阶段数值仿真模型.在流凌期间实测流冰荷载、洪水荷载及风载等作用组合下,计算分析了该桥最大悬臂阶段桥墩和主梁的线形变化和受力特性.结果表明,流冰荷载单独作用对该桥最大悬臂阶段桥墩和主梁线形和内力影响有限,同时在各荷载工况下桥墩及主梁线形和内力均满足桥梁监控要求.     

沥青混合料高温性能指标的全温域试验

针对中面层常用混合料级配,提出使用硬质沥青,SBS改性沥青,高强改性沥青,添加水泥等中面层混合料设计方案,选取抗压模量、抗剪强度和动稳定度作为高温性能评价指标,结合沥青路面温度场,研究混合料在全温域范围内的高温性质.研究结果表明,不同混合料在全温域范围内,力学性质递变规律存在差异,各项高温性能参数存在一定相关性.     

基于网格技术的长江干线碰撞风险评价方法研究

长江作为我国第一也是世界最为繁忙的河流,它的可持续发展和航运安全一直受到社会各界的广泛关注.近年来,随着我国中西部地区的迅猛发展,一方面长江船舶的流量和货物吞吐量与日俱增,另一方面船舶碰撞、搁浅、翻沉、油污、火灾等水上交通事故仍屡次发生,并造成了严重的后果.有鉴于此,结合专家学者们的相关研究成果,在研究船舶交通流、航道状态以及环境影响的基础上,建立了一个基于网格技术的碰撞风险评价模型,并以此对长江干线的碰撞风险进行了评价分析.     

风力发电设备安装船的整船强度数值计算研究

在风力发电设备安装船的典型装载工况下,应用三维势流理论进行波浪诱导载荷长期预报,以主要载荷控制参数为依据进行设计波的选取,应用DNV的SESTRA模块将设计波载荷施加于船体进行船体结构直接计算分析。计算结果表明：船体结构设计均满足要求。     

基于EMTDC/PSCAD的熔断器仿真模型

熔断器作为一种重要的电路开关设备得到广泛应用.运用EMTDC/PSCAD仿真软件,分别基于Cassie电弧模型和Mayr电弧模型搭建了熔断器仿真模块.仿真计算的结果表明,该模块能够准确地模拟熔断器的几种典型工作状态,为后面的仿真研究提供了保证.     

A selection scheme for optimum number of cooperative secondary users in spectrum sensing

An optimization scheme for choosing the optimum number of secondary users in cooperative spectrum sensing based on the cyclostationary feature detection with Neyman-Pearson criterion is proposed in this paper. The optimal soft combination test statistic for the cooperative spectrum sensing based on cyclostationary feature detection is derived according to the generalized likelihood ratio test and its corresponding detection performance is deduced. A target function, considering two important parameters as the resource use efficiency and the number of samples employed by each cooperative secondary user in the system design, is constructed to obtain the optimum number of cooperative secondary users. It can be found that the selection scheme is to make a tradeoff between the system complexity of the cognitive radio network and the global sensing performance of the cooperative spectrum sensing.     

Reputation-based collaborative spectrum sensing scheme in cognitive radio networks

Collaborative spectrum sensing is proposed to improve the detection performance in cognitive radio (CR) networks. However, most of the current collaborative sensing schemes are vulnerable to the interference of the malicious secondary users (SUs). In this paper we propose a reputation-based collaborative spectrum sensing scheme to improve the security of cooperative sensing by mitigating the impacts of misbehaviors. The fusion center calculates the reputation rating of each SU according to their history reports to weight their sensing results in the proposed scheme. We analyze and evaluate the performance of the proposed scheme and its advantages over previous schemes in expansibility and integrity. Simulation results show that the proposed scheme can minimize the harmful influence from malicious SUs.