From Contracts to E-Contracts: Modeling and Enactment

Contracts are complex to understand, represent and process electronically. Usually, contracts involve various entities such as parties, activities and clauses. An e-contract is a contract modeled, specified, executed and enacted (controlled and monitored) by a software system (such as a workflow system). Workflows are used to automate business processes that govern adherence to the e-contracts. E-contracts can be mapped to inter-related workflows, which have to be specified carefully to satisfy the contract requirements. Most workflow models do not have the capabilities to handle complex inter/intra relationships among entities in e-contracts. An e-contract does not adhere to activity/task oriented workflow processes, thus generating a gap between a conceptual model of e-contract and workflow. In this paper, we describe conceptual modeling of e-contracts and present a business process model for e-contract enactment. The enactment of e-contracts necessitates dynamic generation and initiation of workflows during the e-contract execution, besides the static workflows. ER^EC business process model facilitates an integrated approach to e-contracts enactment. Our methodology is illustrated by means of a case study conducted using Financial Messaging Solution contract for banking transactions.     

Workflow View Based E-Contracts in a Cross-Organizational E-Services Environment

In an e-service environment, workflow involves not only a single organization but also a number of business partners. Therefore, workflow inter-operability in such an environment is an important issue for enacting workflows. In this article, we introduce our approach of using workflow views as a fundamental support for E-service workflow inter-operability and for controlled visibility of (sub-)workflows by external parties. We discuss various aspects of a workflow view, and their semantics with example usage. Furthermore, we develop a contract model based on workflow views and demonstrate how management of e-contracts can be facilitated, with an Internet start-up E-service inter-organization workflow example.     

Article 5 of the Rome convention on the law applicable to contractual obligations of 19 June 1980 and consumer E-contracts: the need for reform

The Rome Convention of 19 June 1980 lays down rules relating to the designation of the law applicable to contractual obligations. In certain contractual relationships involving consumers and professionals, Article 5 of the Convention includes specific rules intended to protect consumers. Adopted at a time where the Internet had not yet entered our living rooms and affected our shopping patterns, the Convention is proving inadequate when it comes to protecting consumers entering into e-contracts. The recent introduction of the Green Paper (COM (2002) 654 final) on the conversion of the Convention into a Community instrument and its modernisation reinforces the debate on the necessary adaptation of Article 5 to the realities of e-commerce. This article focuses on some of the changes Article 5 requires in order to afford consumers a better protection in their dealings with retailers via the Internet.     

Analysing legal status of electronic agents in contracting through interactive websites: comparative study of American,English and EU laws developing Iranian legal system

In the modern world, electronic communications play a significant role in national and international electronic transactions. This issue has forced all legal systems to face up to many emerging legal problems in the context of electronic communications, such as the legal status of electronic agents in contracting electronically. Regarding the legal validity of e-contracts made through interactive websites, the legal status of electronic agents which play an important role in this process is questionable to see whether they are akin to real agents in the physical world or they are only a mere tool of communication. The current article tries to analyse this question by criticising a number of theories and some others based on the technical nature of the Internet, the traditional legal rules and principles and the UNCITRAL regulations on e-commerce and also the statues of American, English and EU laws on e-commerce to develop Iranian legal system.     

无线传感器网络密钥管理方案的研究

安全机制中密钥管理方案的研究一直是无线传感器网络的研究热点。从无线传感器网络的安全分析入手,在分类描述分布式和分簇式密钥管理方案并分析其优缺点的基础上,提出几点设计密钥管理方案的研究设想。     

构件搜索中需求描述关键词提取方法

随着主动服务研究的逐渐深入，各项主动服务的关键功能已开始逐步的实现，最大正向匹配算法可以实现构件搜索中用户需求描述的分解和关键词的提取。     

安全组播中一种有效的密钥更新方案

组密钥管理作为安全组播的核心问题之一,已成为近年来研究的热点。该文在分析了已有组密钥管理方案的基础上,针对一对多的通信方式提出了一种有效的密钥管理方案,该方案在有成员变动时,与以往的密钥管理方案相比,大大降低了计算量及通信量,对时延敏感的多播应用来讲,具有非常重要的实用价值。     

无线传感器网络密钥分配协议研究

密钥分配协议对于无线传感器网络的安全起着基础性作用。由于传感器网络大规模、节点资源非常受限、分布式等特点，传统的基于公钥和可信任的密钥分配中心等方式不能实用。本文系统针对传感器网络特点，提出密钥管理协议的需求与性能指标，系统阐述了几种当前比较典型的密钥预分配协议：基于初始信任、随机密钥预分配以及各种改进方案等，分析比较其优缺点，并提出了进一步研究的方向。     

无线传感器网络密钥分布方案研究

无线传感器网络广泛应用于目标跟踪、环境监测、军事感应和地震活动测试等方面。网络安全是无线传感器网络应用的关键因素。在无线传感器网络安全结构中,节点的密钥分布是其中的重要一环。资源有限的大规模无线传感器网络的部署需要高效的节点密钥分布机制。高效的节点密钥分布方案能加强网络连通性、提高抵抗节点捕获攻击的能力、减小节点能量的消耗以及扩展节点通信范围。本文分析了密钥分布的安全要求,着重从密钥的产生、密钥连接的建立和性能方面描述了当前典型的密钥分布方案,并比较和分析了这些算法的特点和安全性能。最后结合该领域当前研究现状,指出无线传感器网络密钥分布未来可能的研究方向。     

基于量子密钥的VPN密钥管理模型研究

随着信息技术的提升,为维护网络安全,采用基于量子密钥的VPN密钥管理模型,并结合量子密钥保密通信的特点,大大提高网络用户信息的安全性,保障数据通信安全。将从VPN密钥管理模型的结构以及特点出发,强调VPN中密钥管理的重要性,分析基于量子密钥的VPN密钥管理模型,根据当前VPN系统中密钥管理的不足,基于量子密钥的VPN密钥管理模型,对VPN网络的安全性进行分析,研究基于量子密钥的VPN密钥管理模型。     

Creating interactive virtual humans: some assembly required

Discusses some of the key issues that must be addressed in creating virtual humans, or androids. As a first step, we overview the issues and available tools in three key areas of virtual human research: face-to-face conversation, emotions and personality, and human figure animation. Assembling a virtual human is still a daunting task, but the building blocks are getting bigger and better every day.     

组播技术综述

组播通信技术提供了一种点对点或多点对多点的数据传输模型 ,作为下一代 Internet应用的重要技术 ,组播相关技术研究引起了广泛关注 .本文从分布式系统特点出发 ,分析了组播研究的内容和特点 ,描述了组播设计所涉及的技术及难点 ,概括了现有工作和相关进展     

基于内容的视频检索关键技术

基于内容的视频检索一直是计算机科学研究的难点问题，该文提出了它的研究问题、检索策略、检索种类和评价指标，指出了存在的问题及解决的方法。这些策略和方法作为北大方正媒体资产管理系统的核心功能，运用于电视台大型视频数据库的检索，取得了比较好的效果。     

一个前向安全的基于签密的密钥协商协议*

安全有效地传递信息是计算机安全通信研究领域的主要目标。借鉴Zheng和张串绒将签密技术运用到密钥协商协议中的思想,利用基于身份的签密方案,提出一种具有前向安全性的密钥协商协议。该协议在具有基于身份的公钥密码体制特点的同时,又拥有签密技术的优点。与已有的方案相比,该密钥协商协议除了具有机密性、认证性、还具有前向安全性的特点。     

轨道车辆动力学与控制研究进展

作为动力学与控制学科的一个分支,车辆动力学与控制方向的研究近年来一直很受重视。轮轨式轨道车辆在基础研究、技术攻关和产品研发等领域不断取得重要进展,这得益于近20年来我国轨道交通领域的快速发展和国家科技部门的大力支持。本文从我国轮轨式轨道车辆的发展趋势、特点和运营过程中遇到的主要问题等研究角度出发,重点介绍了轨道车辆的载荷分析与减振降噪方法,轨道车辆动力学建模、计算方法和新型结构的动态设计,以及轨道车辆关键旋转部件的状态识别等三个方面的研究成果。这些成果在一定程度上反映了作者们目前所关注的问题和拟解决途径,希望能给轨道车辆动力学与控制领域的其他研究者们提供一些借鉴和参考。     

无线传感器网络基于身份的密钥建立协议综述

无线传感器网络(WSN)的高度自治和资源严重受限等特点,使其安全问题比传统Ad hoc网络面临更大的挑战.密钥管理是WSN安全的一个基本问题,密钥建立作为密钥管理的重要内容,必须兼顾安全性和性能等方面因素.综述了WSN基于身份的密钥建立协议.介绍了基于身份密码体制的基本要素,给出了基于身份的密钥协商协议的安全属性和安全模型,详细分析比较了现有的WSN基于身份的密钥建立协议,指出了它们安全性和性能方面的不足,并对未来的研究方向进行了探讨.     

TETRA系统的鉴权机制及攻击方式研究

数字集群通信系统TETRA的鉴权机制包括基站对移动台的鉴权、移动台对基站的鉴权以及双向鉴权等,描述了鉴权密钥的管理方式,通过分析其鉴权机制存在的威胁论述了对其采取的攻击方式,由于鉴权在安全机制中所处的关键地位,对鉴权机制的研究为进一步实施对TETRA系统的攻击奠定了基础,是进行其他形式对抗的前提之一。     

改进的返回式二进制防碰撞算法

作为物联网应用中的关键技术,射频识别（RFID）技术是近年来的热门研究领域。在大规模的RFID应用中,不可避免地会有标签识别的碰撞问题。以每个时隙传输数据的字节数以及搜索命令的发送次数作为参考指标,对已有算法进行分析比较,在已有算法的基础上提出一种改进的返回式二进制防碰撞算法,减少每个时隙数据的传输量和命令搜索次数,使得新的改进算法性能有较大的提升。     

Current research in multirobot systems

As research progresses in distributed robotic systems, more and more aspects of multirobot systems are being explored. This article describes advances in multirobot systems, and surveys the current state of the art. The focus is principally on research that has been demonstrated in physical robot implementations. I have identified eight primary research topics within multirobot systems—biological inspirations, communication, architectures, localization/mapping/exploration, object transport and manipulation, motion coordination, reconfigurable robots, and learning—and discuss the current state of research in these areas. As I describe each research area, I identify some key open issues in multirobot team research, and conclude by identifying several additional open research issues in distributed mobile robotic systems. This work was presented, in part, at the Seventh International Symposium on Artificial Life and Robotics, Oita, Japan, January 16–18, 2002     

智能卡私钥文件潜在风险分析

在病毒、木马泛滥的情况下,智能卡终端的安全性得不到保障,因此在智能卡私钥文件的生命周期中(如产生、更换、撤销过程)仍然存在安全风险,导致以私钥安全为核心的各类PKI应用出现各种问题。为此,介绍原有智能卡安全体系,对私钥在整个智能卡生命周期中的使用进行研究,并对潜在的风险进行全面分析,提出一种基于生产公钥证书的智能卡私钥保护方案。