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Web信息抽取技术研究进展 被引量:19
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作者 陈少飞 郝亚南 +2 位作者 李天柱 徐林昊 杨文柱 《河北大学学报(自然科学版)》 CAS 2003年第1期106-112,共7页
Web信息抽取技术是当今的一个研究热点。目前出现了基于不同原理的多种信息抽取技术,它们具有不同的性能。本文根据信息抽取的原理,对现有的信息抽取技术进行了分类,结合典型的系统,在语义的附加方式、模式的定义方式、规则的表现形式... Web信息抽取技术是当今的一个研究热点。目前出现了基于不同原理的多种信息抽取技术,它们具有不同的性能。本文根据信息抽取的原理,对现有的信息抽取技术进行了分类,结合典型的系统,在语义的附加方式、模式的定义方式、规则的表现形式、语义项的定位方式、对象的定位方式等几方面进行了分析和比较,在此基础上提出了待研究的问题。 展开更多
关键词 WEB信息抽取技术 研究进展 HTML XML 语义 抽取模式 抽取原理 WEB查询 抽取规则
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Water Resource Management in the Intermountain Izeh Plain,Southwest of Iran 被引量:1
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作者 Kalantari.N Pawar.N.J Keshavarzi.M.R 《Journal of Mountain Science》 SCIE CSCD 2009年第1期25-41,共17页
Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more t... Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more than 5 meters reflecting that the aquifer is under stress condition. As a result, interest is focused on application of artificial recharge as an option for groundwater management to augment water supply in this area. Therefore, in the present investigations, suitable sites for artificial recharge were selected by an integrated surface and sub-surface assessment of the area. On the basis of the data collected from four target points, it was realized that the selected sites for artificial recharge could not meet water demand of the area. In this study attention was also paid to utilization of the existing Miangran Lake water as an alternative to combat water shortage for irrigation. The study further indicated that the available Miangran Lake water could be used for irrigation of the reclaimed agricultural land and enabling to convert 20o0 hectares of rain-fed land into irrigation. The total cost to utilize lake water is US$ 2,756,729 and it was estimated that the project could recoup the investment within 5 years which is quite reasonable in this water scarcity prone area. 展开更多
关键词 Artificial recharge STREAM MiangranLake GROUNDWATER Izeh Plain
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