Consistency-driven data quality management of networked sensor systems

With more and more real deployments of wireless sensor network applications, we envision that their success is nonetheless determined by whether the sensor networks can provide a high quality stream of data over a long period. In this paper, we propose a consistency-driven data quality management framework called Orchis that integrates the quality of data into an energy efficient sensor system design. Orchis consists of four components, data consistency models, adaptive data sampling and process protocols, consistency-driven cross-layer protocols and flexible APIs to manage the data quality, to support the goals of high data quality and energy efficiency. We first formally define a consistency model, which not only includes temporal consistency and numerical consistency, but also considers the application-specific requirements of data and data dynamics in the sensing field. Next, we propose an adaptive lazy energy efficient data collection protocol, which adapts the data sampling rate to the data dynamics in the sensing field and keeps lazy when the data consistency is maintained. Finally, we conduct a comprehensive evaluation to the proposed protocol based on both a TOSSIM-based simulation and a real prototype implementation using MICA2 motes. The results from both simulation and prototype show that our protocol reduces the number of delivered messages, improves the quality of collected data, and in turn extends the lifetime of the whole network. Our analysis also implies that a tradeoff should be carefully set between data consistency requirements and energy saving based on the specific requirements of different applications.     

基于DSP2812的静止无功补偿控制器

针对电力系统中无功补偿装置发展的现状,介绍了一种基于DSP2812的静止无功补偿装置控制器的设计.该控制器充分利用了DSP2812内部资源丰富的特点,即响应速度快、动态性能好,系统结构简单、可靠性高、成本低.试验结果表明,该控制器具有优异的性能,可用于低压系统的动态无功补偿.     

下一代跨校区数字化校园网实现策略与研究

我国高等教育的快速发展促使大校合并、校区扩建,VPN技术建设校园网使教学资源得到充分优化利用的一种虚拟教育环境。随中国互联网客户逐年增多,IPv4地址问题日趋严重,互联网向IPv6过渡已是大势所趋。本文从VPN和IPV6升级技术、实施方案等方面讨论下一代跨校区数字化校园网实现策略与研究。     

Types of structural assurance and their relationships with trusting intentions in business-to-consumer e-commerce

This study examines the effects of different types of structural assurance mechanisms on trusting intention in business-to-consumer electronic commerce. Inconsistent results from prior research on structural assurance motivated the current study to further explore the nature of structural assurance. Based on the Institution-based Trust Theory, this paper proposes that different types of structural assurance mechanisms, specifically: seals of approval, vendor-specific guarantees, protections from credit card companies and transaction protections, may have their unique effects on trusting intentions. The results indicate that customer perceptions about seals of approval and vendor-specific guarantees can significantly influence trusting intentions while perceptions about protections from credit card companies, legal systems and technology infrastructures do not.     

基于GIS的高速公路沿线设施管理信息查询系统的设计与实现

将GIS技术引入到高速公路沿线设施管理信息系统,实现沿线设备设施的可视化管理.并就如何在SuperMap平台下实现系统的查询功能进行了探讨.介绍了量子图形数据库,进行关键字段关联的方法实现图形与属性的互查,以及目标对象综合信息查询方法.利用SuperMap Objects 的相关接口函数开发了高速公路沿线设施管理信息查询系统,使用户准确定位并查询感兴趣目标的空间信息、属性信息和综合信息,从而在宏观上把握高速公路上的设备设施,辅助相关人员进行管理和决策.     

基于微腔光学晶体生物传感器的研究进展

多孔硅（PS）与多孔硅微腔晶体（PSM）作为新型功能材料,其独特的光学特性、微电子相容性、滤过性、纳米微孔生长可控性及大的比表面积为生物信号传感提供了一个较为理想的平台,已制备成多种生物传感器应用于血液,细菌,病毒,DNA等的快速检测中。在分析了PS与PSM的结构和性能的基础上,重点介绍了PS与PSM生物传感器的研究现状,并提出开发微型芯片、集成器件和市场化产品将是PS与PSM生物传感器的发展趋势。     

基于web服务的动态工作流引擎设计

工作流引擎作为基于web服务工作流管理系统的重要核心部件,其结构的合理化对整个系统有着至关重要的影响.采用动静态定义链接的方法来对传统工作流模型进行改进,以实现动态工作流模型.在此基础上,设计出一种基于此工作流模型的动态工作流引擎,并详细剖析了引擎设计中的动态服务代理机制.与同类研究相比,该引擎具有更好的跨平台性以及适应性.     

用VB标签控件实现动态效果

在VB程序设计里．标签通常是作为在窗口里显示文字信息的。用活标签的常用属性。并合理使用计时器控件。就能够呈现出动态的文字效果。为窗口界面增添活力。     

基于IP网络门禁控制系统通信模块的设计与开发

对基于IP网络的门禁控制系统整体设计方案及原理进行了简要的分析,提出了在系统框架上将B／S模式和C／S模式相结合的设计思想,同时通过引入通信模块,在管理软件和控制器之间架起了专用的TCP通道,给出了一种实现TCP／IP通信的新方法,并加入门禁控制器主动通信方式,测试证明该通信平台运行稳定,能够提高门禁控制系统的工作效率。     

基于DSP的柑橘分级系统硬件设计

文章介绍了基于DSP的柑橘分级系统的硬件方案所使用的技术.成像系统将采集的图像信息通过视频编码、解码后输入DSP进行预处理,并提取特征值,与标称值进行比较,从而确定每个柑橘的质量级别,实现分级.