The broad sense overlap concept and types of tree crown overlap were defined in the paper through analping function between the factors of tree crown overlap. The formulas of overlap area and overlap rate were derive...The broad sense overlap concept and types of tree crown overlap were defined in the paper through analping function between the factors of tree crown overlap. The formulas of overlap area and overlap rate were derived from definite integral form. At the same time, many formulas were acquired while the projective figures of tree crown were circle. Application ways of these formulae were illustrated with a concrete caculation process.展开更多
Based on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information, the concept model and concept system of coral islets and reef are proposed.Then ...Based on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information, the concept model and concept system of coral islets and reef are proposed.Then twin-tree remote sensing information model for different kinds of reef is constructed by using abstracted islets and reef's primitive, and the structure recognition system for coral islets and reef type is developed.展开更多
We applied the decision tree algorithm to learn association rules between webpage’s category(pornographic or normal) and the critical features.Based on these rules, we proposed an efficient method of filtering pornog...We applied the decision tree algorithm to learn association rules between webpage’s category(pornographic or normal) and the critical features.Based on these rules, we proposed an efficient method of filtering pornographic webpages with the following major advantages: 1) a weighted window-based technique was proposed to estimate for the condition of concept drift for the keywords found recently in pornographic webpages; 2) checking only contexts of webpages without scanning pictures; 3) an incremental learning mechanism was designed to incrementally update the pornographic keyword database.展开更多
提出一种基于广义后缀树的概念生成算法(generalized suffix tree based concept generation algorithm,GSTCG),将背景中所有对象的属性序列及其后缀建立为一棵广义后缀树,并根据广义后缀树产生候选概念;其次,合并具有相同对象集合的候...提出一种基于广义后缀树的概念生成算法(generalized suffix tree based concept generation algorithm,GSTCG),将背景中所有对象的属性序列及其后缀建立为一棵广义后缀树,并根据广义后缀树产生候选概念;其次,合并具有相同对象集合的候选概念,再根据规则对候选概念进行扩展;最后,删除冗余的候选概念后得到全部形式概念。在两类不同参数人工数据集上的实验结果表明,GSTCG算法与NextClosure算法在所有背景上得到的概念数量一致,且前者具有更优的时间性能。展开更多
随着网络与信息技术的快速发展,导致网络上产生了大量的电子文本,而文本间的相似度计算是文本处理的一种重要手段。对于大规模的文本集,通常采用向量空间模型(vector space model,VSM)进行文本表示,但是该方法面临着文本向量维度较高及...随着网络与信息技术的快速发展,导致网络上产生了大量的电子文本,而文本间的相似度计算是文本处理的一种重要手段。对于大规模的文本集,通常采用向量空间模型(vector space model,VSM)进行文本表示,但是该方法面临着文本向量维度较高及文本语义相似度难以度量的问题。提出一种改进的文本相似度计算方法,从大量的特征空间中选择出具有代表性的元数据特征向量元素,以降低向量空间的维度;构建领域概念树并设计基于领域概念树的文本相似度算法,对领域概念中广泛存在的同义词进行处理,以提高文本之间语义相似度度量的性能。实验结果表明:通过降维和概念相似度计算可提高文本相似度计算的性能。展开更多
文摘The broad sense overlap concept and types of tree crown overlap were defined in the paper through analping function between the factors of tree crown overlap. The formulas of overlap area and overlap rate were derived from definite integral form. At the same time, many formulas were acquired while the projective figures of tree crown were circle. Application ways of these formulae were illustrated with a concrete caculation process.
文摘Based on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information, the concept model and concept system of coral islets and reef are proposed.Then twin-tree remote sensing information model for different kinds of reef is constructed by using abstracted islets and reef's primitive, and the structure recognition system for coral islets and reef type is developed.
基金supported by MOST under Grant No.MOST 103-2410-H-004-112
文摘We applied the decision tree algorithm to learn association rules between webpage’s category(pornographic or normal) and the critical features.Based on these rules, we proposed an efficient method of filtering pornographic webpages with the following major advantages: 1) a weighted window-based technique was proposed to estimate for the condition of concept drift for the keywords found recently in pornographic webpages; 2) checking only contexts of webpages without scanning pictures; 3) an incremental learning mechanism was designed to incrementally update the pornographic keyword database.
文摘提出一种基于广义后缀树的概念生成算法(generalized suffix tree based concept generation algorithm,GSTCG),将背景中所有对象的属性序列及其后缀建立为一棵广义后缀树,并根据广义后缀树产生候选概念;其次,合并具有相同对象集合的候选概念,再根据规则对候选概念进行扩展;最后,删除冗余的候选概念后得到全部形式概念。在两类不同参数人工数据集上的实验结果表明,GSTCG算法与NextClosure算法在所有背景上得到的概念数量一致,且前者具有更优的时间性能。
文摘随着网络与信息技术的快速发展,导致网络上产生了大量的电子文本,而文本间的相似度计算是文本处理的一种重要手段。对于大规模的文本集,通常采用向量空间模型(vector space model,VSM)进行文本表示,但是该方法面临着文本向量维度较高及文本语义相似度难以度量的问题。提出一种改进的文本相似度计算方法,从大量的特征空间中选择出具有代表性的元数据特征向量元素,以降低向量空间的维度;构建领域概念树并设计基于领域概念树的文本相似度算法,对领域概念中广泛存在的同义词进行处理,以提高文本之间语义相似度度量的性能。实验结果表明:通过降维和概念相似度计算可提高文本相似度计算的性能。
