基于云计算的数据安全风险及防御策略研究

云计算因其存储容量大和计算能力强等优点深得人心,然而云技术却为数据安全带来新的威胁。由于云平台与用户间存在大量数据交互,故在整个数据生命周期中存在的一系列安全风险。本文针对这些数据安全风险从国家监管、专业人员的技术研发、云供应商的可信服务和云相关人员的防范意识这四个方面来展开研究,提出了相应的数据安全保护模型和防御策略,能够较好的解决云计算数据安全风险问题。     

云计算下基于信任的防御系统模型

由于云计算的动态性和开放性,云环境中频频出现恶意攻击行为,为了保障云计算的安全,结合可信云的思想,提出一个云计算下基于信任的防御系统模型。该模型通过实时监控获取用户的行为证据并加以规范;提出一种新的基于模糊层次分析法（FAHP）的用户行为信任评估方法,逐步确定各行为证据的权重,实现行为信任的科学量化评估;利用多种检测引擎对可疑文件进行全面检测和综合决策,为云中用户提供最大限度的安全防御。实验结果表明,该系统模型能有效消除不良用户的恶意攻击行为、降低病毒等给用户带来的损失,达到云端和客户端双向防御的目的。     

基于Web行为轨迹的应用层DDoS攻击防御模型

为了有效防御应用层分布式拒绝服务攻击（DDoS）,定义了一种搭建在Web应用服务器上的基于Web行为轨迹的防御模型。把用户的访问行为抽象为Web行为轨迹,根据攻击请求的生成方式与用户访问Web页面的行为特征,定义了四种异常因素,分别为访问依赖异常、行为速率异常、轨迹重复异常、轨迹偏离异常。采用行为轨迹化简算法简化行为轨迹的计算,然后计算用户正常访问网站时和攻击访问时产生的异常因素的偏离值,来检测针对Web网站的分布式拒绝服务攻击,在检测出某用户产生攻击请求时,防御模型禁止该用户访问来防御DDoS。实验采用真实数据当作训练集,在模拟不同种类攻击请求下,防御模型短时间识别出攻击并且采取防御机制抵制。实验结果表明,Web行为轨迹的防御模型能够有效防御针对Web网站的分布式拒绝服务攻击。     

基于大数据的网络安全防御技术及模型

本文在对目前网络安全防御技术不足进行分析的基础上,提出基于大数据的网络安全防御技术并构建了相应的防御模型,该研究将促进网络安全防御技术在大数据环境下的发展,为大数据在网络安全领域的应用提供思路,为同类其他研究提供参考和借鉴。     

对计算机软件安全问题的分析及其防御策略

计算机软件安全是指保护计算机软件系统自身安全以及保证软件系统正常运行,也是保护信息系统数据安全的一个重要方面。计算机软件安全涉及的领域面临着严重的威胁。为此,提出了计算机软件安全问题的防御策略,要求用户树立安全意识,加以防范,重视解决计算机软件的安全问题。     

山石网科构建以AI为核心的云安全防护体系

基于对人工智能多年的积累和实践,5月31日,山石网科在长沙的“未来已至-AI定义的云计算数据中心安全技术发展峰会”上,正式推出了“AI定义的云计算数据中心安全防护体系”.体系包括：高性能的云计算数据安全防护平台X10800;基于AI三大威胁检测能力：垃圾邮件防御服务,僵尸网络C2防御服务,IP信誉库服务;高性能2U云数据中心入侵防御系统;智能感知、随需而变的云计算安全解决方案;以及为用户数据安全能力赋能的云数据库审计与防护解决方案.     

基于双向防御的网络大数据无损加密算法仿真

针对传统方法未对加密过程进行约束,导致加密后的网络大数据易受到入侵.提出基于双向防御的网络大数据无损加密算法.将隐私数据源变成数值并按照所处方位排序,同时把排序完毕的方位数据划分成桶,优化其分布均匀性,增大每个桶中点的数目但低于设定阈值,使用保护序加密算法把桶中的数据实行加密,并保证加密后数值的大小顺序和原始一致,把数据隐私加密过程约束成加密函数的运算,在此基础上,建立大数据动态安全SAT双向防御模型,规范用户数据,判断网络外来数据的安全性,实现网络大数据的无损加密.实验结果表明,所提方法能够有效避免网络大数据隐私的泄露,网络大数据检索效率、加密效率较高,并且具有显著的防入侵性能,且加密后数据安全可靠性较高.     

基于大数据分析的网络安全防御技术研究

目前,网络安全防御技术功能单一,防御能力低,为此提出了研究基于大数据分析的网络安全防御技术。通过建立感知数据源,确定要采集的数据源,采集防御链条下的终端、边界、服务和应用等各类安全数据,并收集威胁网络安全的数据,形成网络访问行为数据摘要。在此基础上,引入数据检测技术,保障传输的安全性,达到维护网络安全的目的,同时,利用大数据的分析结果,根据攻击者的行为数据进行监测并提前报警,完成基于大数据分析的网络安全防御技术设计。     

综合防御体系在教学管理信息系统中的构建

在为应用系统构建安全体系时,人们往往将注意力放在网络安全和数据安全方面,而软件系统管理、物理安全等问题却容易被忽视.本文以教学管理信息系统为例,阐述如何从网络安全、物理安全、软件系统管理、数据安全等多个方面构建应用系统的综合防御体系.     

基于数据特征融合的多层次网络空间安全防御系统

文章提出基于数据特征融合的多层次网络空间安全防御系统。将搭载智能化流量模型和基于用户行为单向防御技术的H3C AFC作为系统的异常流量清洗硬件装置,通过旁路部署和在线部署实现对网络空间多层次的安全防护。在软件设计阶段,融合网络空间的流量规模、吞吐量以及流量变化幅度特征,当实时流量数据与融合特征之间的差值超出网络允许上限时,将其作为H3C AFC的清洗目标,以此实现对网络空间安全的多层次防御。测试结果表明,网络空间安全态势值在设计系统的保护下,受攻击影响后的下降幅度仅为0.12。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.