Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient ...Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient and the relation theorem of heredity-variation. The attribute dependence of f-variation coefficient and the relation of heredity-variation are important characteristics of S-rough sets. From such discussion, this paper puts forward the heredity mining off-knowledge and the algorithm of heredity mining, also gives its relative application.展开更多
In the era of big data,the conflict between data mining and data privacy protection is increasing day by day.Traditional information security focuses on protecting the security of attribute values without semantic ass...In the era of big data,the conflict between data mining and data privacy protection is increasing day by day.Traditional information security focuses on protecting the security of attribute values without semantic association.The data privacy of big data is mainly reflected in the effective use of data without exposing the user’s sensitive information.Considering the semantic association,reasonable security access for privacy protect is required.Semi-structured and self-descriptive XML(eXtensible Markup Language)has become a common form of data organization for database management in big data environments.Based on the semantic integration nature of XML data,this paper proposes a data access control model for individual users.Through the semantic dependency between data and the integration process from bottom to top,the global visual range of inverted XML structure is realized.Experimental results show that the model effectively protects the privacy and has high access efficiency.展开更多
In this paper we deal with Twitter and the presence of the keyword “Macedonia” in tweets over a period of time. We searched for the same term in three different languages, i.e. “Μακεδονíα”, “Macedoni...In this paper we deal with Twitter and the presence of the keyword “Macedonia” in tweets over a period of time. We searched for the same term in three different languages, i.e. “Μακεδονíα”, “Macedonia” and “Македонска - Македониjа”, since we are primarily interested in views from Greece and FYROM without excluding views from other regions. We use methods from Social Network Analysis (SNA) in order to create networks of users, calculate some main network metrics, measure user importance and investigate the presence of possible fragmentations—communities among them. We furthermore proceed to a form of content analysis, using pairs of words within tweets, in order to obtain main ideas, trends and public views that circulated over the network.展开更多
Sequential point trees provide the state-of-the-art technique for rendering point models, by re-arranging hierarchical points sequentially according to geometric errors running on GPU for fast rendering. This paper pr...Sequential point trees provide the state-of-the-art technique for rendering point models, by re-arranging hierarchical points sequentially according to geometric errors running on GPU for fast rendering. This paper presents a view dependent method to augment sequential point trees by embedding the hierarchical tree structures in the sequential list of hierarchical points. By the method, two kinds of indices are constructed to facilitate the points rendering in an order mostly from near to far and from coarse to fine. As a result, invisible points can be culled view-dependently in high efficiency for hardware acceleration, and at the same time, the advantage of sequential point trees could be still fully taken. Therefore, the new method can run much faster than the conventional sequential point trees, and the acceleration can be highly promoted particularly when the objects possess complex occlusion relationship and viewed closely because invisible points would be in a high percentage of the points at finer levels.展开更多
本文论述了基于视点的连续 L o D算法在动态虚拟地形场景绘制中的应用。我们通过分析规则格网数字高程模型的规律性 ,推导了 3个与视点相关的判据来动态简化地形 :1图像空间误差 ;2视锥台相交性 ;3节点方向性。实验结果证明 ,该算法在...本文论述了基于视点的连续 L o D算法在动态虚拟地形场景绘制中的应用。我们通过分析规则格网数字高程模型的规律性 ,推导了 3个与视点相关的判据来动态简化地形 :1图像空间误差 ;2视锥台相交性 ;3节点方向性。实验结果证明 ,该算法在基本保持视觉效果不变的情况下 ,极大地提高了虚拟地形场景的绘制速度。展开更多
基金This project was supported by the National Natural Science Foundation of China (60364001), the Shandong ProvincialNatural Science Foundation of China (Y2004A04) and Fujian Provincial Education Foundation of China(JA04268).
文摘Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient and the relation theorem of heredity-variation. The attribute dependence of f-variation coefficient and the relation of heredity-variation are important characteristics of S-rough sets. From such discussion, this paper puts forward the heredity mining off-knowledge and the algorithm of heredity mining, also gives its relative application.
基金This work was supported by Funding of Jiangsu Innovation Program for Graduate Education KYLX_0285,the National Natural Science Foundation of China(No.61602241)the Natural Science Foundation of Jiangsu Province(No.BK20150758)the pre-study fund of PLA University of Science and Technology.
文摘In the era of big data,the conflict between data mining and data privacy protection is increasing day by day.Traditional information security focuses on protecting the security of attribute values without semantic association.The data privacy of big data is mainly reflected in the effective use of data without exposing the user’s sensitive information.Considering the semantic association,reasonable security access for privacy protect is required.Semi-structured and self-descriptive XML(eXtensible Markup Language)has become a common form of data organization for database management in big data environments.Based on the semantic integration nature of XML data,this paper proposes a data access control model for individual users.Through the semantic dependency between data and the integration process from bottom to top,the global visual range of inverted XML structure is realized.Experimental results show that the model effectively protects the privacy and has high access efficiency.
文摘In this paper we deal with Twitter and the presence of the keyword “Macedonia” in tweets over a period of time. We searched for the same term in three different languages, i.e. “Μακεδονíα”, “Macedonia” and “Македонска - Македониjа”, since we are primarily interested in views from Greece and FYROM without excluding views from other regions. We use methods from Social Network Analysis (SNA) in order to create networks of users, calculate some main network metrics, measure user importance and investigate the presence of possible fragmentations—communities among them. We furthermore proceed to a form of content analysis, using pairs of words within tweets, in order to obtain main ideas, trends and public views that circulated over the network.
基金A preliminary version of this paper appeared in Proc. Pacific Graphics 2005, Macao. The work is supported by the National Basic Research 973 Program of China （Grant No. 2002CB312102）, the National Natural Science Foundation of China （Grant Nos. 60373051, 60473105） and the Research Grant of the University of Macao.
文摘Sequential point trees provide the state-of-the-art technique for rendering point models, by re-arranging hierarchical points sequentially according to geometric errors running on GPU for fast rendering. This paper presents a view dependent method to augment sequential point trees by embedding the hierarchical tree structures in the sequential list of hierarchical points. By the method, two kinds of indices are constructed to facilitate the points rendering in an order mostly from near to far and from coarse to fine. As a result, invisible points can be culled view-dependently in high efficiency for hardware acceleration, and at the same time, the advantage of sequential point trees could be still fully taken. Therefore, the new method can run much faster than the conventional sequential point trees, and the acceleration can be highly promoted particularly when the objects possess complex occlusion relationship and viewed closely because invisible points would be in a high percentage of the points at finer levels.
