Mining Sensor Data in Cyber-Physical Systems

A Cyber-Physical System （CPS） integrates physical devices （i.e.,sensors） with cyber （i.e.,informational） components to form a context sensitive system that responds intelligently to dynamic changes in real-world situations.Such a system has wide applications in the scenarios of traffic control,battlefield surveillance,environmental monitoring,and so on.A core element of CPS is the collection and assessment of information from noisy,dynamic,and uncertain physical environments integrated with many types of cyber-space resources.The potential of this integration is unbounded.To achieve this potential the raw data acquired from the physical world must be transformed into useable knowledge in real-time.Therefore,CPS brings a new dimension to knowledge discovery because of the emerging synergism of the physical and the cyber.The various properties of the physical world must be addressed in information management and knowledge discovery.This paper discusses the problems of mining sensor data in CPS：With a large number of wireless sensors deployed in a designated area,the task is real time detection of intruders that enter the area based on noisy sensor data.The framework of IntruMine is introduced to discover intruders from untrustworthy sensor data.IntruMine first analyzes the trustworthiness of sensor data,then detects the intruders＇ locations,and verifies the detections based on a graph model of the relationships between sensors and intruders.     

Ontology-Based Semantic Multi-agent Framework for Micro-grids with Cyber Physical Concept

The distributed hierarchical control based on multi-agent system(MAS) is the main control method of micro-grids.By allowing more flexible interactions between computing components and their physical environments,cyber physical system(CPS) presents a new approach for the distributed hierarchical engineering system,with micro-grids included.The object of this paper is to integrate the CPS concept with MAS technology and propose a new control framework for micro-grids.With the analysis of the operating mode and control method of micro-grids,the cyber physical control concepts of ontologybased semantic agent are discussed.Then an MAS-based architecture of cyber physical micro-grid system and an intelligent electronic device(IED) function structure are proposed.Finally,in order to operate and test the cyber physical micro-grid concept,an integrated simulation model is presented.     

从读者卡功能谈国家数字图书馆服务

从读者卡功能入手,介绍了国家图书馆二期暨国家数字图书馆的服务,包括数字资源门户、网上读书、短信服务、一卡通收费系统、盲人数字图书馆等.     

一种基于最小路径的多播路由优化算法

信息物理融合系统(Cyber-Physical Systems,CPS)底层是传感器、控制器和执行器等异构节点构成的无线自组网络,不同节点之间需要通过通信网络传送给感兴趣目标节点,传统的无线自组织网络一般采用单播或广播技术,但是这些往往实时性不高,通信开销大,不利于在CPS中受限节点间通信.该文针对信息物理融合系统中无线多播路由问题构建网络模型,演化为最小路径问题,数学模型为约束Steiner最小树问题,并针对该NP难问题通过启发式算法求解,再通过贪婪思想构建一种最小路径多播路由算法.最后通过与uCast以及SenCast等经典的多播路由算法仿真比较,得出其算法在实时性以及能耗等方面性能优异.     

Specification and Verification of a Topology-Aware Access Control Model for Cyber-Physical Space

The cyber-physical space is a spatial environment that integrates the cyber and physical worlds to provide an intelligent environment for users to conduct their day-to-day activities. Mobile users and mobile objects are ubiquitous in this space, thereby exerting tremendous pressure on its security model. This model must ensure that both cyber and physical objects are always handled securely in this dynamic environment. In this paper,we propose a systematic solution to be able to specify security policies of the cyber-physical space and ensure that security requirements hold in these policies. We first formulate a topology configuration model to capture the topology characteristics of the cyber and physical worlds. Then, based on this model, a Topology-Aware CyberPhysical Access Control model(TA-CPAC) is proposed, which can ensure the security of the cyber and physical worlds at the same time by adjusting permission assignment dynamically. Then, the topology configuration and TA-CPAC models are formalized by bigraphs and Bigraph Reactive System(BRS), respectively, allowing us to use model checking to rationalize the consequences of the evolution of topological configurations on the satisfaction of security requirements. Finally, a case study on a building automation access control system is conducted to evaluate the effectiveness of the proposed approach.     

基于攻击图的物理信息系统网络安全风险评估

在过去十年中,针对电力系统等典型物理信息系统的网络攻击事件数量有所增加。现有物理信息系统风险评估技术只对OT系统或IT系统一个物理信息系统层的影响进行评估,难以精确反应物理信息系统的真实风险程度。本文提出了一种基于攻击图的物理信息系统定量风险评估方法,首先,基于物理信息系统的实际双系统层架构,构建了物理信息系统风险评估模型;同时综合考虑攻击者的能力、攻击行为的特点和目标网络的特点,给出了分析攻击路径选择概率的方法;然后,分别从OT系统和IT系统两个层面综合分析物理信息系统的影响因子,量化系统的风险值。最后,构建物理信息系统评估模型并进行仿真,验证了所提方法的有效性和准确性。     

A Survey of Language-Based Approaches to Cyber-Physical and Embedded System Development

As computers continue to advance, they are becoming more capable of sensing, interacting, and communicating with the physical and cyber world. Medical devices, electronic braking systems in automotive applications, and industrial control systems are examples of the many Cyber-Physical Systems(CPS) that utilize these computing capabilities. Given the potential consequences of software related failures in such systems, a high degree of safety, security, and reliability is often required. Programming languages are important tools used by programmers to develop CPS. They provide a programmer with the ability to transform designs into machine code. Of equal importance is their ability to detect and avoid programming mistakes. The development of CPS has predominantly been accomplished using the C programming language. Although C is a powerful language, it lacks features present in other languages that facilitate the development of reliable systems. This has prompted research into language-based alternatives for improving program quality through the use of programming languages. This paper presents an overview of the characteristics of embedded and cyber-physical systems and the associated requirements imposed on programming languages. This is followed by a survey of relevant research into languagebased methods for creating safe, reliable, and robust software for CPS.     

面向离散制造的混杂数控自治系统设计

研究离散制造中混杂数控生产线的智能化控制问题.引入智能感知、智能决策与智能执行等智能制造技术,构建生产线数控设备的联网协同机制,实现类似流程制造中自动化生产及无人值守的自治控制.基于信息物理融合系统(cyber physical systems,CPS)设计混杂数控自治系统(autonomous system for hybrid NC,ASHNC),提出具体架构与分层模型.采用WPF技术开发原型系统,并且在多个知名企业所构建的数控生产线中得到应用.实际效果验证了系统的可行性.     

电力信息物理系统易损性分析方法

针对电力信息物理系统（CPS）体系复杂、网络耦合、易损性分析困难这一现状,以近年来国内外电力系统毁伤相关研究成果为基础,构建了电力CPS的毁伤树模型.根据电力CPS节点重要性与故障级联毁伤特性,提出了一种基于节点重要性的电力CPS易损性分析方法,构建了易损性评估模型,并结合实例进行了分析说明.结果表明,该模型可用于电力信息物理系统的生存力研究,为目标抗毁伤结构设计提升提供支撑.      

智能变电站安全脆弱性评估方法

基于IEC61850的智能变电站严重依赖于信息和通信技术,信息安全成为不得不面对的新问题。从智能变电站信息安全脆弱性和传统信息安全评估手段的局限性2个方面对智能变电站的安全现状进行分析,提出了可覆盖智能变电站信息系统和控制系统的安全脆弱性评估方法。该方法分别采用已知漏洞扫描技术、未知漏洞挖掘技术以及静态评估方法,分别对智能变电站的各层设备和日常管理进行安全评估工作。通过对智能变电站实验环境的现场实际测试,发现了存在于信息系统、自动化设备中的系统漏洞,验证了该方法评估智能变电站信息安全脆弱性的有效性。应用该方法可以实现对智能变电站信息和控制系统潜在安全漏洞的多方位管控,提升智能变电站的整体安全。     

重要数据信息的网络安全控制与防范

针对网络数据信息面临的威胁,从物理安全、访问控制、加密技术等几个方面,对重要数据信息的网络安全策略进行了深入分析,并对网络数据信息的安全与防范技术进行了展望.     

浅谈网络英语构词特点

网络飞速发展的今天,网络语言应运而生,英语在网络语言中依旧是使用最广泛的语言之一。掌握网络英语词语的语用特点和构词方法,了解和熟悉最现代的英语语言,有助于提高英语交际能力。     

网络财务的发展及其面临的问题

随着倩息技术快速发展。全球信息处理网络化成为历史发展的必然趋势,互联网推动着企业的财务管理进入一个新的发展阶段——网络财务．在定义网络财务内涵的基础上,讨论了网络财务的功能特点,分析了网络财务发展中面临的问题,提出了网络财务的实施策略．     

企业实施网络营销的竞争优势与运用策略

结合国内外网络发展现状,阐述了网络营销特有的营销特征和竞争优势,从培育网上市场、网络营销运用和网络营销管理三方面探讨我国企业实网络营销的必要性,提出企业实施网络营销的运用策略。     

校园网络文化建设对西藏大学生带来的利弊及对策

校园网络文化是高等学校在培养人才、传承人类文化、创造时代文化的过程中,基于计算机与通信技术这种物质基础创造的一切财富和精神的总和。西藏高校校园网络已初具规模,除了校园网站,还建有各类教学和管理等网上应用服务,功能齐全而丰富,因此加快高校网络文化的建设已是迫在眉睫的问题。校园网络文化建设是提高西藏高校精神文明建设的科技含量,保证网络文化的先进性本质、抵制和消除网络不良文化影响的重要手段。网络文化不仅有它的正面影响,同时存在着负面影响。文章主要论述了网络文化对西藏大学生带来的利弊并提出相应的对策,有利于在校园开展网络文化建设。     

从电影的兴衰看视觉文化走向

在抽象语言世界里，人的感觉日益萎缩。电影第一次把人类的眼睛还给人类，并借助梦幻之路使人重返想象界。电影的衰落原因复杂，电视对它的，中击是其一。电视变成了生活本身，进一步消除了影像与现实之间的界限。随着网络的发展，虚幻的现实变成虚拟的现实。     

谈谈高等师范院校的计算机文化建设

信息时代的到来，给计算机文化增添了新的内涵，师范院校是普及计算机文化的主战场，师范院校计算机文化建设的重点是计算机应用环境的营造。     

WinXP下实现基于Snort的入侵检测系统

随着网络攻击行为的日益猖獗,入侵检测技术成为网络安全研究的热点问题。简要介绍了入侵检测技术和Snort,联合使用Snort,Apache,ACID,MySQL等在WinXP环境下搭建了一个小型入侵检测系统。     

物理实验测量误差的合成

凡测量都存在误差.在物理实验中主要分为系统误差、随机误差、粗大误差.由于误差分类.就存在着进行合成的问题.又由于在国际、国内引用了不确定度一词取代误差,不确定度就用来评测测量的质量,这样也就存在了不确定度的合成问题.     

Formalization of the Abstract Architecture of MAS Based on FIPA Specification

The FIPA specification of MAS (multi-agent system)is accepted by most of the applications of MAS in the world, and has been used in many projects. This paper draws an abstract architecture from the FIPA based MAS, and gives fon-rmlization about it.