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彭泽伟 《数字社区&智能家居》2009,5(3):1573-1574,1577
以2005年颁布的国标草案《信息安全风险评估指南》为主要指导,并参考NISTSP800—30的管理控制思想、评估方法以及威胁发生可能性的计算方法,给出了一个具有可操作性的信息安全风险评估量化模型。 相似文献
96.
基于属性识别理论的网络威胁评估方法 总被引:1,自引:0,他引:1
针对网络威胁评估问题,提出一种基于属性识别理论的网络威胁评估方法。通过提取一段时间内网络攻击事件的指标,采用熵值确定权重并建立模型,对攻击事件进行评估、分级,进而量化出该段时间内网络的威胁程度。实例分析结果表明,该方法简单、实用,能够有效进行网络威胁的评估。 相似文献
97.
基于攻击路径图的威胁评估方法 总被引:1,自引:0,他引:1
为解决复杂系统安全威胁评估问题,研究并建立了基于攻击路径图的系统安全威胁模型。该模型首先提出了漏洞利用可能性及利用结果的评估标准,进而在分析漏洞之间利用关系的基础上生成目标系统的攻击路径图,并以图论、概率论等理论作为基本方法对将复杂攻击路径分解为以串、并联形式为基本构成单元的简单路径,从而降低了安全威胁评估问题的规模和难度,实现了对漏洞威胁以及攻击路径威胁的量化评估。 相似文献
98.
Maze problems represent a simplified virtual model of the real environment and can be used for developing core algorithms
of many real-world application related to the problem of navigation. Learning Classifier Systems (LCS) are the most widely
used class of algorithms for reinforcement learning in mazes. However, LCSs best achievements in maze problems are still mostly
bounded to non-aliasing environments, while LCS complexity seems to obstruct a proper analysis of the reasons for failure.
Moreover, there is a lack of knowledge of what makes a maze problem hard to solve by a learning agent. To overcome this restriction
we try to improve our understanding of the nature and structure of maze environments. In this paper we describe a new LCS
agent that has a simpler and more transparent performance mechanism. We use the structure of a predictive LCS model, strip
out the evolutionary mechanism, simplify the reinforcement learning procedure and equip the agent with the ability to Associative
Perception, adopted from psychology. We then assess the new LCS with Associative Perception on an extensive set of mazes and
analyse the results to discover which features of the environments play the most significant role in the learning process.
We identify a particularly hard feature for learning in mazes, aliasing clones, which arise when groups of aliasing cells
occur in similar patterns in different parts of the maze. We discuss the impact of aliasing clones and other types of aliasing
on learning algorithms. 相似文献
99.
Many networked human-machine interface systems have a distributed structure for certain purposes such as more computational
power, tele-presence, collaboration, and portability. However, network delays are inevitable in the distributed structure,
and often make sensory information delivered behind time to the user. In the literature, the effect of network delays on the
quality of information presentation has been considered with respect to task performances in most cases. In this paper, we
pay attention to a more stringent criterion, namely whether perceptual artifacts caused by network delays are perceptible by the user. We examined minimum perceptible
visual and/or haptic rendering delays by measuring their discrimination thresholds between normal and delayed virtual environments
with and without a task, and report the results in this paper. We also provide a simple guideline for determining whether
active delay compensation algorithms are required in a networked human-machine interface system by comparing representative
network delays to the measured discrimination thresholds.
Recommended by Guest Editor Phill Kyu Rhee. This work was supported in parts by a grant R01-2006-000-10808-0 and a NRL grant
R0A-2008-000-20087-0 both from KOSEF and by a ITRC support program C1090-0804-0002 from IITA, all funded by the Korea government.
In Lee is a Ph.D student in Computer Science and Engineering at POSTECH, of Korea. He received the B.S. degree in Information and
Communication Engineering from Sungkyunkwan University in 2006. His research interests include haptics, virtual reality, and
human-computer interaction.
Seungmoon Choi is an Assistant Professor in Computer Science and engineering at POSTECH, Korea. He received the B.S. and M.S. degrees in
Control and Instrumentation Engineering from Seoul National University in 1995 and 1997, respectively, and the Ph.D. degree
in Electrical and Computer Engineering from Purdue University in 2003. His research areas include haptics, virtual reality,
data perceptualization, and applied perception. 相似文献
100.
科技进步带来丰盛的商品,我们的生活方式、消费需求发生极大转变,社会进入感性消费时代,本文论述了消费心理变化的主观和客观因素,探索感性消费需求心理变化趋势,呼吁企业和设计师关注消费需求的变化,探索感性消费需求下的个性化设计艺术。 相似文献