无线局域网高效地址自动分配协议

在无线局域网(MANET-Mobile Ad Hoc Networks)中IP地址如何无冲突的分配一直是一个重要的论题。本文将使用聚集自动分配和有效地址选择给出一个高效的分配方案。无线局域网是由一系列平等的主机所构成,我们需要一个IP地址自动分配协议来对这些移动的主机进行控制,而在该协议制定中很好的考虑到这一特性。     

移动定位系统在高速公路管理中的应用

移动定位系统的应用对规范通行费用拆分方式、提高拆分透明度和公平性具有重要意义。文章分析了目前广西高速公路管理中存在的问题,同时结合移动定位定义、系统的构成及基本原理,介绍移动定位系统在高速公路管理中的具体应用情况及达到的效果。     

基于Android移动平台的车货匹配设计与实现

移动客户端可以实现车货匹配模式的及时、高效、逼真体验、高度可视化，提供方便快捷的服务。根据车货对接流程，设计基于Android系统的车货对接模式。系统实现货主发布货源、查询货物报价、报价处理、查询交易记录功能，实现车主注册车辆、查询注册车辆、根据车辆查询匹配货源、报价、查询记录等功能。本系统能够让货主在平台上发布信息，对于车主、货主之间物流运输，快速、准时的达成物流运输协议有实际意义。     

Development of origin–destination matrices using mobile phone call data

In this research, we propose a methodology to develop OD matrices using mobile phone Call Detail Records (CDR) and limited traffic counts. CDR, which consist of time stamped tower locations with caller IDs, are analyzed first and trips occurring within certain time windows are used to generate tower-to-tower transient OD matrices for different time periods. These are then associated with corresponding nodes of the traffic network and converted to node-to-node transient OD matrices. The actual OD matrices are derived by scaling up these node-to-node transient OD matrices. An optimization based approach, in conjunction with a microscopic traffic simulation platform, is used to determine the scaling factors that result best matches with the observed traffic counts. The methodology is demonstrated using CDR from 2.87 million users of Dhaka, Bangladesh over a month and traffic counts from 13 key locations over 3 days of that month. The applicability of the methodology is supported by a validation study.     

智能车载导航与电话系统设计

基于S3C2410微处理器、WinCE 6.0嵌入式操作系统、GSM、GPS、GPRS和标准的RS232串口通讯等技术设计了一款嵌入式智能车载导航与电话系统。介绍了系统主要模块的电路设计以及软件系统主要功能的设计流程和实现过程。该系统可以方便实现车载电话、卫星导航、无线上网等基本功能,还可以通过网络与车辆监控中心连接实现在线导航、车辆调度、车辆监控等服务,在未来的车联网和智能交通系统中将有一定的应用前景。该系统平台具有成本低、体积小、便于安装、可靠性强和高稳定性等特点。     

Estimating near-road pollutant dispersion: A model inter-comparison

A model inter-comparison study to assess the abilities of steady-state Gaussian dispersion models to capture near-road pollutant dispersion has been carried out with four models (AERMOD, run with both the area-source and volume-source options to represent roadways, CALINE, versions 3 and 4, ADMS and RLINE). Two field tracer studies are used: the Idaho Falls tracer study and the Caltrans Highway 99 tracer study. Model performance measures are calculated using concentrations (observed and estimated) that are paired in time and space, since many of the health related questions involve outcomes associated with spatially and temporally distributed human activities. All four models showed an ability to estimate the majority of downwind concentrations within a factor of two of the observations. RLINE, AERMOD-V, and ADMS, also have the capability to predict concentrations upwind of the roadway that result from low-speed meandering of the plume. Generally, RLINE, ADMS, and AERMOD (both source types) had overall performance statistics that were broadly similar, while CALINE 3 and 4 both produced a larger degree of scatter in their concentration estimates. The models performed best for near-neutral conditions in both tracer studies, but had mixed results under convective and stable conditions.     

移动式信号设备故障记录分析装置

采用便携采集模块及综合采集设备进行现场采集,并配合数据分析软件,对于铁路现场偶发信号故障及曲线波动异常等不明故障进行监测及分析,可有效提高信号设备故障定位的准确性、方便性及时效性。     

粒子群优化算法在多用户检测中的应用

粒子群优化算法是一类有效的随机全局优化技术。它利用一个粒子群搜索解空间,每个粒子表示一个被优化问题的解,通过粒子间的相互作用发现复杂空间中的最优区域。多用户检测技术是直扩序列码分多址中的一项关键技术。将粒子群优化算法应用于多用户检测中,能有效抑制多址干扰,实现结构简单、鲁棒性强的目的,在加速收敛的同时降低了计算复杂度。仿真结果表明,这种多用户检测器充分利用了粒子群优化算法的优良特性,与传统的码分多址接收机、基于进化算法的多用户检测器和基于遗传算法的多用户检测器比较,在误码率和收敛速度等方面都有显著的改善。     

广东省手机游戏产业发展研究

分析了广东省手机游戏产业的发展概况,基于中国移动互联网与智能手机等高速发展的时代背景下,分析广东省手机游戏总体发展状况,并进一步分析腾讯、银汉、网易等广东省代表性手机游戏企业主要发展状况,在其基础上思考当前手机游戏发展的问题,并对手机游戏的发展提出建议.     

移动实景技术在飞来峡展示系统中的应用研究

文中通过对移动实景技术从路线设计、数据采集、数据质检、数据处理、数据输出等各环节进行详细阐述,对处理过程中的关键技术进行了介绍,分析了基于移动实景技术的飞来峡展示系统实现的各种功能,为其他应用移动实景技术系统建设提供了很好的范例。