考虑时间参数的网络安全态势评估模型研究

针对已有网络安全态势评估由于缺乏考虑数据源时变性而造成的证据源证据不可靠、评估出现误差的问题,引入时变函数来刻画多源证据的时变性,提出时变D-S证据理论,用以提高证据的可靠性。使用改进的时变D-S证据理论方法对多传感器的证据进行融合,得到威胁的发生概率,并在此基础上提出带有时间参数的网络安全态势评估层次化模型;最后利用网络实例数据,对所提出的网络安全态势评估模型进行了验证。实验对比结果表明,该模型对实际网络运行情况的评估更符合实际情况。     

一种融合多源数据的网络安全态势评估模型

网络安全态势评估是目前网络安全领域的研究热点之一。对国内外已有的网络安全态势评估方法进行了分析和比较,提出一种融合多源数据的网络安全态势定量评估模型。同时考虑主机和链路对网络安全态势的影响,将网络安全态势指标归纳为主机安全指标和链路安全指标。采用改进D-S证据理论融合日志记录、告警信息和其他探针数据,得到精简的主机安全事件集合和链路安全事件集合。依据相应的服务信息分别计算主机安全态势和链路安全态势,实现网络安全态势定量评估。通过网络仿真软件构建网络实例,对所提出的网络安全态势评估模型进行了验证,实验结果表明该模型可以准确地对网络安全态势进行定量评估,评估结果能够客观地反映网络安全态势的变化趋势。     

基于贝叶斯攻击图的网络安全量化评估研究

针对攻击图在评估网络安全时节点关系复杂、存在含圈攻击路径、只能反映网络静态风险等问题, 将攻击图与贝叶斯理论结合, 提出贝叶斯攻击图的概念, 简化了攻击图并通过优化算法避免了含圈路径的产生; 通过引入攻击证据与CVSS评分系统, 提出了一种新的面向脆弱点的网络安全量化评估方法, 基于贝叶斯攻击图对网络整体及局部的安全状况进行实时动态评估。通过在实际网络中的实验验证了该方法的可行性及有效性, 与传统评估方法相比, 该方法能够动态地反映网络安全的态势变化情况。     

基于自律计算的网络安全态势感知模型

针对当前网络安全管理的复杂性和态势感知过程缺乏自适应性等问题,提出一个基于自律计算的网络安全态势感知模型。利用自律反馈机制对态势提取进行实时分析;根据提取的态势信息,从攻击和防御两个角度出发,采用层次分析法建立多层次多角度的网络安全态势评估模型;依据过去和当前网络安全态势,采用改进的遗传神经网络方法建立网络安全态势预测模型。仿真实验结果表明,具有自律反馈机制的态势感知模型可以有效增强系统的自适应能力。     

基于信息融合的网络安全态势评估模型

安全态势评估是近年来国内外在网络安全领域的研究热点之一.对已有的安全态势评估方法进行了详细分析和比较,针对网络安全中多数据源的特点,提出基于信息融合的网络安全态势评估模型,引入改进的D-S证据理论将多数据源信息进行融合,利用漏洞信息和服务信息,经过态势要素融合和节点态势融合计算网络安全态势,绘制安全态势曲线图,同时对态势计算结果进行时间序列分析,从而实现网络安全趋势的预测.最后利用网络实例数据,对所提出的网络安全态势评估模型和算法进行了验证,结果表明该模型比已有成果更加有效和准确.     

基于改进决策树的通信网络安全态势感知方法

为应对日益复杂的网络风险与攻击，提出基于改进决策树的通信网络安全态势感知方法。首先，设计通信网络安全态势感知的技术架构，采集并预处理通信网络安全态势感知信号；其次，应用改进决策树算法提取网络安全态势要素，采用D-S证据理论计算通信网络安全态势感知量化结果；最后，进行实验对比分析。实验结果表明，该方法具有精确性与可靠性，能够有效提升通信网络的安全态势感知水平。     

一种基于D-S证据理论的P2P信任模型

基于D-S证据理论的信任模型不能合成证据信息。为此,采用重新分配冲突概率与引入权重系数的策略,提出一种改进的D-S证据合成规则IDSECR,并将其用于P2P网络的信任建模,建立一种基于D-S证据理论的P2P信任模型,解决传统信任模型无法处理冲突程度高而引起的信任度计算不准确问题。仿真实验结果表明,在恶意节点攻击的情况下,该模型具有较高的交易成功率。     

基于D-S证据理论的网络安全态势预测方法研究

为了获取网络在未来一段时间内的安全态势状况,提出了一种基于D-S证据理论的网络安全态势预测方法.构建了基于D-S证据理论的网络安全态势预测模型,用于融合历史和当前网络安全态势对未来网络安全态势的影响,降低其中的不确定性,获得下一时刻网络处于各类安全状态的概率,避免对网络安全态势的绝对预测.通过实验验证了该方法的有效性和准确性,为网络安全态势预测提供了一种新思路.     

基于攻击检测的网络安全风险评估方法

为了实时评估网络安全风险,建立了用于描述主机安全状态的隐马尔可夫模型,以入侵检测系统的报警信息作为模型输入,计算主机处于被攻击状态的概率.针对攻击报警,提出了一种新的攻击成功概率计算方法,然后结合攻击威胁度计算主机节点的风险指数.最后利用主机节点重要性权重与节点风险指数量化计算网络风险.实例分析表明,该方法能够动态绘制网络安全风险态势曲线,有利于指导安全管理员及时调整安全策略.     

网络安全态势感知模型研究

网络安全态势感知是实现网络安全监控的一种新技术,也是目前信息安全的研究热点之一.在理清国内外研究现状的基础上,提出了基于简单加权法和灰色理论的网络安全态势感知模型.模型的建立主要分为当前网络安全态势评估建模和未来网络安全态势预测建模两部分,当前网络安全态势评估模型是依据各种服务受到攻击的威胁程度采用简单加权法建立的,而未来网络安全态势预测模型则是依据过去和当前网络安全态势采用灰色理论建立的.经仿真实验验证,该模型合理可行.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

正~~     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate