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111.
Each vulnerability scanner (VS) represents, identifies and classifies vulnerabilities in its own way, thus making the different scanners difficult to study and compare. Despite numerous efforts by researchers and organisations to solve the disparity in vulnerability names used in the different VSs, vulnerability categories have still not been standardised. This paper highlights the importance of having a standard vulnerability category set. It also outlines an approach towards achieving this goal by generating a standard set of vulnerability categories. A data-clustering algorithm that employs artificial intelligence is used for this purpose. The significance of this research results from having an intelligent technique that aids in the generation of standardised vulnerability categories in a relatively fast way. In addition, the technique is generic in the sense that it allows one to accommodate any VS currently known on the market to create such vulnerability categories. Another benefit is that the approach followed in this paper allows one to also compare various VSs currently available on the market. A prototype is presented to verify the concept.  相似文献   
112.
Recent researches have demonstrated the importance of concept map and its versatile applications especially in e-Learning. For example, while designing adaptive learning materials, designers need to refer to the concept map of a subject domain. Moreover, concept maps can show the whole picture and core knowledge about a subject domain. Research from literature also suggests that graphical representation of domain knowledge can reduce the problems of information overload and learning disorientation for learners. However, construction of concept maps typically relied upon domain experts in the past; it is a time consuming and high cost task. Concept maps creation for emerging new domains such as e-Learning is even more challenging due to its ongoing development nature. The aim of this paper is to construct e-Learning domain concept maps from academic articles. We adopt some relevant journal articles and conference papers in e-Learning domain as data sources, and apply text-mining techniques to automatically construct concept maps for e-Learning domain. The constructed concept maps can provide a useful reference for researchers, who are new to the e-Leaning field, to study related issues, for teachers to design adaptive learning materials, and for learners to understand the whole picture of e-Learning domain knowledge.  相似文献   
113.
Detailed Real-Time Urban 3D Reconstruction from Video   总被引:2,自引:0,他引:2  
The paper presents a system for automatic, geo-registered, real-time 3D reconstruction from video of urban scenes. The system collects video streams, as well as GPS and inertia measurements in order to place the reconstructed models in geo-registered coordinates. It is designed using current state of the art real-time modules for all processing steps. It employs commodity graphics hardware and standard CPU’s to achieve real-time performance. We present the main considerations in designing the system and the steps of the processing pipeline. Our system extends existing algorithms to meet the robustness and variability necessary to operate out of the lab. To account for the large dynamic range of outdoor videos the processing pipeline estimates global camera gain changes in the feature tracking stage and efficiently compensates for these in stereo estimation without impacting the real-time performance. The required accuracy for many applications is achieved with a two-step stereo reconstruction process exploiting the redundancy across frames. We show results on real video sequences comprising hundreds of thousands of frames.  相似文献   
114.
This paper presents an innovative neural network-based quality prediction system for a plastic injection molding process. A self-organizing map plus a back-propagation neural network (SOM-BPNN) model is proposed for creating a dynamic quality predictor. Three SOM-based dynamic extraction parameters with six manufacturing process parameters and one level of product quality were dedicated to training and testing the proposed system. In addition, Taguchi’s parameter design method was also applied to enhance the neural network performance. For comparison, an additional back-propagation neural network (BPNN) model was constructed for which six process parameters were used for training and testing. The training and testing data for the two models respectively consisted of 120 and 40 samples. Experimental results showed that such a SOM-BPNN-based model can accurately predict the product quality (weight) and can likely be used for various practical applications.  相似文献   
115.
一种新的非线性分形压缩算法   总被引:1,自引:1,他引:0       下载免费PDF全文
郑莹  李光耀  孙燮华 《计算机工程》2008,34(11):21-22,2
提出一种基于Julia-CK集和Logistic映射的非线性分形压缩算法。用Carotid-Kundalini函数生成Julia-CK集,并用Logistic映射生成伪随机数填充量化表。将量化后的Julia-CK集分割成4 4的小图像块,再变换成圆盘。圆盘经过旋转后重新变换为正方形,对Julia-CK集进行适当的分类。编码时在同类中寻找匹配的图像块,扩充了原有的仿射变换,得到一个丰富且可通用的压缩字典,有效地打破图像和数据字典之间的一一对应关系。实验表明,相比于Barnsley提出的经典分形压缩方法,新算法使压缩比提高约36%,重建图像的峰值信噪比提高约27%,具有良好的压缩比,获得了高质量的解码图像。  相似文献   
116.
虚拟三维场景与二维电子地图交互系统研究   总被引:1,自引:0,他引:1       下载免费PDF全文
提出并建立了一个虚拟三维场景与二维电子地图交互系统。介绍了系统的组成和各部分实现的功能。对虚拟场景的数据组织、场景数据读入、观察者位置的确定及交互功能的实现等给出解决方案,给出了实现的代码及画面。该系统利用二维电子地图简洁性、宏观性的特点,通过与虚拟三维场景间的互响应减少观察者在虚拟三维场景中漫游所产生的迷失感,在实际应用中取得了较好的效果。  相似文献   
117.
游戏编程是当今程序设计的一个热点,开发过程会遇到各种各样的问题。通过限制构造函数和拷贝函数,设计一个单体全局管理类,可以避免不合适的调用。采用分块技术加栽地图,可以在时空性能上优化游戏。阐述了D3D的空间坐标变换。分析了万向节死锁问题发生的原因,并提出了解决办法。  相似文献   
118.
随着多媒体技术及其相关技术的发展,多媒体制作得到了广泛的重视,应用范围越来越广。现今网络技术的飞速发展及其广泛的应用,Authorware针对网络用户提供了一系列多媒体信息编辑、传输、网上发布的解决方案,为CAI教学在网上实现提供了良好的条件。  相似文献   
119.
改进自组织映射神经网络方法是将常规自组织映射神经网络方法结合确定性水平,对网络的输入矢量进行预处理。通过实验比较了这种改进的自组织映射神经网络识别方法与常规的自组织映射神经网络识别方法的识别效果,在识别性能上有了很大的提高。  相似文献   
120.
基于复合混沌动力系统的图像加密算法设计   总被引:1,自引:0,他引:1       下载免费PDF全文
本文通过对部分数字化混沌图像加密算法的分析研究,设计了一个基于复合离散混沌动力系统的对称图像加密算法。该对称图像加密算法充分利用混沌变化的特性,以Logistic映射和Chebyshev映射生成的混沌序列为初始序列,结合对图像的切割、拉伸、折叠变换,充分打乱图像像素间的相关性,使得针对这两个混沌映射的现有分析方法不再有效,并且可以实现较高的加密速度。实验结果证明了算法的有效性和计算速度。  相似文献   
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