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81.
82.
计算机网络安全隐患与应急响应技术 总被引:1,自引:0,他引:1
随着计算机技术的发展,计算机网络的应用领域和应用人群急剧增加,网络安全问题也日益严重。因此,论述计算机网络安全,现代计算机网络受到的攻击手段及保障计算机网络安全的应急技术等,以提高计算机网络安全性。 相似文献
83.
阐述了贵州省疾病控制和预防中心目前阶段的工作成绩和存在的问题。在此基础上,设计了基于传染病学时空传播模型的突发公共卫生事件的应急响应服务系统。系统通过以事件驱动的服务动态整合机制,联合调度分布式的多种信息资源,进行多部门协同办案,为公共安全应急管理体系的建设提供了良好的技术支撑。 相似文献
84.
为了把移动雷达实时数据传输到北京市气象局,通过对比多种无线通信方式以及卫星通信的优缺点等方法建立了一套卫星通信系统。结果表明:本系统在应急、网络速率、安全等方面都能满足移动雷达系统对数据通信的要求。这套系统的设计将对应急系统的建立具有一定的指导意义。 相似文献
85.
The popularity of distance education has grown rapidly over the last decade in Taiwan’s higher education, yet many fundamental teaching–learning issues are still in debate. While teacher–student interaction is a key success factor in distance education, little work has been done on the teachers. The intent of this research was to clarify teacher’s perceptions on key distance education issues and to develop a discernible typology of different groups of teachers based on their perceptions. Because there may be a gulf between teachers and the technology used in distance education, the target of this study was teachers in information related departments in Taiwan’s colleges, who were more familiar with current technology. Factor analysis and cluster analysis were used to derive the typology. Five higher-level issue constructs emerged from the factor analysis: learning effect, customization, administrative challenges, geographic and resource integration, and instructional design challenges. Four groups of teachers, namely the skeptics, the optimists, the mild-promising group, and the outlier, were identified using cluster analysis of teachers’ perceptions on these five higher-level issue constructs. The profiles of the four groups of teachers were summarized and implications were discussed, which should provide useful insights to the policy makers of higher education on distance education decisions. 相似文献
86.
A study investigating the accuracy of interpersonal perception in Internet Bulletin Board Systems (BBS) and the variables that affect the accuracy were conducted in two phases: in the phase one, 58 participants were selected from the BBS which was built on the Internet in advance. During the phase two, participants were requested to complete the Myers–Briggs Type Indicator (MBTI) to assess their personalities, and to choose another member in the BBS as their “target”. The assessment packets were then administered to the participants in the following order: the demographic and Internet use survey, the MBTI used by the judge to assess their target’s personality, and the relationship survey between judge and target. The results showed that 76.7% participants made the correct judgment on two to three out of four dimensions of the personality type. The correlation analysis indicated that the variables affected the accuracy were from four aspects: judge, target, relationship and similarity. The binary logistic regression analysis showed that the target’s personality, the judge’s education level, the similarity between them, the stereotypes and projection played important roles on the accuracy. Possibilities for future research on this issue are also briefly discussed. 相似文献
87.
Theodore Pachidis John Lygouras Kostas Tarchanidis 《Journal of Intelligent and Robotic Systems》2008,51(4):385-420
In this paper, first HumanPT architecture for low cost robotic applications is presented. HumanPT architecture differs than
other architectures because it is implemented on existing robotic systems (robot robotic controller) and exploits the minimum
communication facilities for real-time control that these systems provide. It is based on well-known communication methods
like serial communication (USB, RS232, IEEE-1394) and windows sockets (server–client model) and permits an important number
of different type of components like actuators, sensors and particularly vision systems to be connected in a robotic system.
The operating system (OS) used is Microsoft Windows, the most widely spread OS. The proposed architecture exploits features
of this OS that is not a real-time one, to ensure – in case that the robotic system provide such a facility – control and
real time communication with the robotic system controller and to integrate by means of sensors and actuators an important
number of robotic tasks and procedures. As implementation of this architecture, HumanPT robotic application and experimental results concerning its performance and its implementation in real tasks are provided.
HumanPT robotic application, developed in Visual C++, is an integrated, but simultaneously an open-source software that can be adapted
in different types of robotic systems. An important number of robotic tasks or procedures including sensors and particularly
vision systems can be generated and executed. Small enterprises by means of the proposed architecture and the open source
software can be automated at low cost enhancing in this way their production. 相似文献
88.
89.
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
90.
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