新型Koch型缺陷地面结构低通滤波器设计

提出了一种新型Koch型缺陷地面结构（KDGS）,设计了两款基于分形缺陷地 面结构的低通滤波器。仿真结果表明：所设计的两种新型低通滤波器3 dB截止频率分别 为3.10 GHz和3.20 GHz,10 dB阻带带宽分别为8.75 GHz和12.25 GHz ,通带插入损耗均小于0.10 dB。该滤波器设计方法简单,性能好且成本低,在无线通 信中很有应用前景。     

一种基于WiMAX技术的交通噪声监测网

提出了一种基于WiMAX宽带无线接入技术的交通噪声监测网,给出了利用宽带无线 应急通信车构建交通噪声监测网的框架,深入讨论了符合IEEE 802.16标准的交通噪声监测 终端平台的 功能和组成。该噪声监测网可以很好地解决交通噪声的大范围和全天候实 时动态监测等问题,为交通噪声的规范管理和技术决策提供了重要的依据。     

无线传感器网络中检测女巫攻击的节点定位方法

为了有效抵制女巫攻击,在攻击存在的情况下提高无线传感器网络节点的定位精度, 分析、总结了女巫攻击所固有的薄弱环节,提出了基于接收功率验证的检测女巫攻击的节点 安 全定位方法。检测机制分为两步,首先检测节点通过比较接收功率,从所接收的全部信标节 点中选择出距其距离相同的信标节点,列为可疑Sybil节点,然后通过邻居节点间的信息交 互和距离验证,最终检测出攻击节点,利用去除了Sybil节点的信标节点集合实现定位。仿 真实验显示,当存在攻击时,检测成功概率能达到95%以上,定位精度提高了9～11.64 m,表明该方法能有效检测女巫攻击,实现节点安全定位。     

旅游业商业模式的未来——免费

旅游业盈利模式有收费的＂门票盈利＂模式和免费的＂服务盈利＂模式。目前我国旅游开发企业主要采用收费的＂门票盈利＂模式,这种商业模式管理简单且利润相对稳定,但也有诸多弊端,如收入来源过于单一、企业发展空间受限、抑制顾客的消费、不利于旅游开发企业的经营能力建设等。随着旅游对象的扩大及旅游范围限制的缩小,旅游业的竞争会越来越激烈,通过扩展旅游链的利润源,而对链条终端进行免费的模式将是旅游业商业模式的必然选择。据此设计了5种免费模式：免费加收费模式、景点内消费模式、品牌授权模式、旅游地产模式和政府补贴模式。     

Fighting churn with rate plan right-sizing: a customer retention strategy for the wireless telecommunications industry

Prior literature suggests that wireless customers have difficulty in predicting their usage requirements and they often subscribe to rate plans that are not financially optimized. However, the benefits of having wireless customers on optimal rate plans are relatively unknown due to limited research in this area. This paper aims to address this knowledge gap and presents a customer retention strategy for the wireless telecommunications industry. The usage and payment records of 1403 Canadian post-paid wireless customers are examined over a 3.7-year study period. Pearson's χ ² test and hazard function graph are used to reveal how customer churn rate is influenced by rate plan suitability. The statistical analysis demonstrates that customers who are using optimal rate plans have lower churn rate than those with non-optimal ones.     

Accrual Accounting and the Efficiency of the Core Public Sector

This paper evaluates the 'microeconomic' case for the extension of accrual accounting to the core government for the purposes of performance measurement, competitive tendering and asset management. Having found the microeconomic case to be weak, it suggests that it is the potential role of accrual accounting as an indicator of the fiscal stance of the public sector (particularly in respect to intergenerational equity) which provides a convincing rationale for its introduction in core government, and that this has significant methodological implications.     

本地多点分配业务(LMDS)——新兴的宽带固定无线接入技术

本地多点分配业务(Local Multipoint Distribution Services,LMDS)是一种新兴的宽带固定无线接入技术,能为多个固定用户提供点对多点的宽带无线接入和多种宽带交互式数据、话音和视频传输业务,适合在城市的高密度用户地区和业务量大的用户中使用。以美国为主的厂商积极在美国本土和国际市场大规模开展LMDS业务。目前LMDS在我国仍处于试验和试用阶段。     

我国基础设施收费证券化的初探

资产证券化作为一种创新的融资方式,自从20世纪70年代在美国兴起以来,在西方国家已有相关的实践和研究,基础设施收费证券化作为资产证券化的一种,在我国对于扩大建设资金来源,促进基础设施的改善具有重要意义.在我国现有法律制度和环境的限制下,离岸模式可以有效地避免国内法律法规的障碍,可作为我国基础设施收费证券化的交易模式.     

Driving Forces for M-Commerce Success

Abstract

Is m-commerce just an extension or a subset of e-commerce? Will it turn out to be just more hype? In this paper we discuss the realities of m-commerce and the major differences between mobile commerce and Internet-based e-commerce. Based on this understanding, we identify key factors that must be taken into consideration in order to design valuable m-com-merce applications. We emphasize that the success of m-commerce relies on the synergy of three driving forces: technology innovation, evolution of a new value chain, and active customer demand.     

基于DM3730的无线视频监控系统

基于TMS320DM3730处理器和无线网络,设计一款无线视频监控系统。该监控系统以Linux为操作系统,采用MT9P031图像传感器采集视频,利用DSP端的H.264算法进行视频压缩编码,视频数据可通过无线网络传输到客户端浏览器进行实时显示。