Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares ...Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares （STLS） problem.The solution of the STLS problem for passive location can be obtained using the inverse iteration method.It also expatiates that both the STLS algorithm and the CTLS algorithm have the same location mean squares error under certain condition.Finally, the article presents a kind of location and tracking algorithm for moving target by combining STLS location algorithm with Kalman filter （KF）.The efficiency and superiority of the proposed algorithms can be confirmed by computer simulation results.展开更多
网页具有丰富的内容和复杂多变的结构,现有的网页信息提取技术解决了单记录型简单页面的信息提取问题,但是对于多记录型复杂页面的信息提取效果往往不佳。文中提出了一种全新的基于可视块的复杂网页信息自动化提取算法(Visual Block Bas...网页具有丰富的内容和复杂多变的结构,现有的网页信息提取技术解决了单记录型简单页面的信息提取问题,但是对于多记录型复杂页面的信息提取效果往往不佳。文中提出了一种全新的基于可视块的复杂网页信息自动化提取算法(Visual Block Based Information Extraction,VBIE),通过启发式规则构建可视块与可视块树,然后通过区域聚焦、噪声过滤及可视块筛选,实现了对复杂网页中数据记录的提取。该方法摒弃了以往算法对网页结构的特定假设,无需对HTML文档进行任何人工标记,保留了网页的原始结构,且能够在单页面上实现无监督的信息提取。实验结果表明,VBIE的网页信息提取精确度最高可达100%,在主流搜索引擎的结果页面和社区论坛的帖子页面上的F1均值分别为98.5%和96.1%。相比目前方法中在复杂网页上提取效果较好的CMDR方法,VBIE的F1值提高了近16.3%,证明了该方法能够有效解决复杂网页的信息提取问题。展开更多
More web pages are widely applying AJAX （Asynchronous JavaScript XML） due to the rich interactivity and incremental communication. By observing, it is found that the AJAX contents, which could not be seen by traditi...More web pages are widely applying AJAX （Asynchronous JavaScript XML） due to the rich interactivity and incremental communication. By observing, it is found that the AJAX contents, which could not be seen by traditional crawler, are well-structured and belong to one specific domain generally. Extracting the structured data from AJAX contents and annotating its semantic are very significant for further applications. In this paper, a structured AJAX data extraction method for agricultural domain based on agricultural ontology was proposed. Firstly, Crawljax, an open AJAX crawling tool, was overridden to explore and retrieve the AJAX contents; secondly, the retrieved contents were partitioned into items and then classified by combining with agricultural ontology. HTML tags and punctuations were used to segment the retrieved contents into entity items. Finally, the entity items were clustered and the semantic annotation was assigned to clustering results according to agricultural ontology. By experimental evaluation, the proposed approach was proved effectively in resource exploring, entity extraction, and semantic annotation.展开更多
对于结构性代码变换,基于Token的同源性检测技术缺乏抽象提取手段,难以识别和定位结构化信息。为此,针对代码同源性检测结构化匹配进行了研究,在LCS(longest common sequence)算法中融入了跳变信息保留、结构边界划分、窗口搜索、计数...对于结构性代码变换,基于Token的同源性检测技术缺乏抽象提取手段,难以识别和定位结构化信息。为此,针对代码同源性检测结构化匹配进行了研究,在LCS(longest common sequence)算法中融入了跳变信息保留、结构边界划分、窗口搜索、计数重置、有效序列界定等逻辑,用于Token摘要的结构化信息匹配,提出了一种结构化匹配同源性代码检测技术,并通过实际工程代码样本进行多种场景的实验测试。实验表明,该方法能够高效识别代码结构化信息,对于代码同源性检测是有效的。展开更多
文摘Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares （STLS） problem.The solution of the STLS problem for passive location can be obtained using the inverse iteration method.It also expatiates that both the STLS algorithm and the CTLS algorithm have the same location mean squares error under certain condition.Finally, the article presents a kind of location and tracking algorithm for moving target by combining STLS location algorithm with Kalman filter （KF）.The efficiency and superiority of the proposed algorithms can be confirmed by computer simulation results.
文摘网页具有丰富的内容和复杂多变的结构,现有的网页信息提取技术解决了单记录型简单页面的信息提取问题,但是对于多记录型复杂页面的信息提取效果往往不佳。文中提出了一种全新的基于可视块的复杂网页信息自动化提取算法(Visual Block Based Information Extraction,VBIE),通过启发式规则构建可视块与可视块树,然后通过区域聚焦、噪声过滤及可视块筛选,实现了对复杂网页中数据记录的提取。该方法摒弃了以往算法对网页结构的特定假设,无需对HTML文档进行任何人工标记,保留了网页的原始结构,且能够在单页面上实现无监督的信息提取。实验结果表明,VBIE的网页信息提取精确度最高可达100%,在主流搜索引擎的结果页面和社区论坛的帖子页面上的F1均值分别为98.5%和96.1%。相比目前方法中在复杂网页上提取效果较好的CMDR方法,VBIE的F1值提高了近16.3%,证明了该方法能够有效解决复杂网页的信息提取问题。
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciencesthe National High-Tech R&D Program of China(2008BAK49B05)
文摘More web pages are widely applying AJAX （Asynchronous JavaScript XML） due to the rich interactivity and incremental communication. By observing, it is found that the AJAX contents, which could not be seen by traditional crawler, are well-structured and belong to one specific domain generally. Extracting the structured data from AJAX contents and annotating its semantic are very significant for further applications. In this paper, a structured AJAX data extraction method for agricultural domain based on agricultural ontology was proposed. Firstly, Crawljax, an open AJAX crawling tool, was overridden to explore and retrieve the AJAX contents; secondly, the retrieved contents were partitioned into items and then classified by combining with agricultural ontology. HTML tags and punctuations were used to segment the retrieved contents into entity items. Finally, the entity items were clustered and the semantic annotation was assigned to clustering results according to agricultural ontology. By experimental evaluation, the proposed approach was proved effectively in resource exploring, entity extraction, and semantic annotation.
文摘对于结构性代码变换,基于Token的同源性检测技术缺乏抽象提取手段,难以识别和定位结构化信息。为此,针对代码同源性检测结构化匹配进行了研究,在LCS(longest common sequence)算法中融入了跳变信息保留、结构边界划分、窗口搜索、计数重置、有效序列界定等逻辑,用于Token摘要的结构化信息匹配,提出了一种结构化匹配同源性代码检测技术,并通过实际工程代码样本进行多种场景的实验测试。实验表明,该方法能够高效识别代码结构化信息,对于代码同源性检测是有效的。
