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一种基于维基百科的中文词语相关度学习算法
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作者 黄岚 杜友福 《中文信息学报》 CSCD 北大核心 2016年第3期36-45,共10页
词语相关程度计算是语义计算的基础。维基百科是目前最大、更新最快的在线开放式百科全书,涵盖概念广,概念解释详细,蕴含了大量概念间关联关系,为语义计算提供了丰富的背景知识。然而,中文维基百科中存在严重的数据稀疏问题,降低了中文... 词语相关程度计算是语义计算的基础。维基百科是目前最大、更新最快的在线开放式百科全书,涵盖概念广,概念解释详细,蕴含了大量概念间关联关系,为语义计算提供了丰富的背景知识。然而,中文维基百科中存在严重的数据稀疏问题,降低了中文词语相关度计算方法的有效性。针对这一问题,该文利用机器学习技术,提出一种新的基于多种维基资源的词语相关度学习算法。在三个标准数据集上的实验结果验证了新算法的有效性,在已知最好结果的基础上提升了20%—40%。 展开更多
关键词 词语相关度 维基百科 中文信息处理 回归 链接结构
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石化装置设备腐蚀数据的图形化展示技术研究与应用 被引量:1
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作者 李启锐 龙添昌 +2 位作者 王松钦 魏泽佳 梁伟森 《石油化工设备技术》 CAS 2015年第2期51-55,7-8,共5页
石化装置的设备结构复杂、腐蚀检测数据量大。通过对装置的管道图和工艺流程图进行研究分析,发现其中的管道具有区域性和分类性。根据该特性把装置图分解为具有包含关系的管道区、管道种类和单体图,形成了四级图形化腐蚀数据导航。应用... 石化装置的设备结构复杂、腐蚀检测数据量大。通过对装置的管道图和工艺流程图进行研究分析,发现其中的管道具有区域性和分类性。根据该特性把装置图分解为具有包含关系的管道区、管道种类和单体图,形成了四级图形化腐蚀数据导航。应用数据库技术建立该导航的数据结构。应用计算机软件技术对该导航的功能进行了设计与实现。实际应用表明,该技术可以大大提高腐蚀数据的查询速率,降低误查概率。 展开更多
关键词 腐蚀数据 工艺流程图 分解 图形链接 四级导航
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一种基于超链接结构的向量空间模型改进算法
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作者 原福永 褚蓓蓓 《中文信息学报》 CSCD 北大核心 2005年第4期68-71,77,共5页
在基于向量空间模型的信息检索系统中,TF-IDF算法被广泛的应用在基于关键字的信息检索中。然而,对于网页独特的超链接结构,需要有一种技术在表示网页内容的同时将与它相邻链接的网页内容考虑进去。本文分析了向量空间模型的实质,并找出... 在基于向量空间模型的信息检索系统中,TF-IDF算法被广泛的应用在基于关键字的信息检索中。然而,对于网页独特的超链接结构,需要有一种技术在表示网页内容的同时将与它相邻链接的网页内容考虑进去。本文分析了向量空间模型的实质,并找出了其精度低的原因,在传统模型基础上提出了一种基于网页超链接结构的向量空间模型改进算法。实验分析表明改进后的算法与原算法相比检索精确度提高了10%,在一定程度上改善了检索效果。 展开更多
关键词 计算机应用 中文信息处理 搜索引擎 信息检索 向量空间模型 超链接
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Minimum Amounts of Extracting Solvent of (A<sub>1</sub>A<sub>2</sub>&middot;&middot;&middot;A<sub><i>t</i>-1</sub>)/(A<sub>2</sub>A<sub>3</sub>&middot;&middot;&middot;A<sub><i>t</i></sub>) Countercurrent Extraction Separation
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作者 Fu-Xiang Cheng Sheng Wu +4 位作者 Song-Ling Wang Bo Zhang Yan Liu Chun-Sheng Liao Chun-Hua Yan 《Advances in Materials Physics and Chemistry》 2015年第8期325-336,共12页
Minimum amounts of extracting solvent and scrubbing agent solution (denoted as Smin and Wmin respectively) mean the theoretical minimal requirements for chemicals to achieve a specified separation duty, and therefore ... Minimum amounts of extracting solvent and scrubbing agent solution (denoted as Smin and Wmin respectively) mean the theoretical minimal requirements for chemicals to achieve a specified separation duty, and therefore attract more concerns in the process design of countercurrent extraction separation. Over the past decade, hyperlink extraction technology has been widely used in rare earth separation industry in China with the target to decrease chemical consumption as well as pollution discharges. However, the equations of Smin and Wmin derived in the earlier version of the theory of countercurrent extraction can only be correctly applied to two-component separation and become invalid for hyperlink processes. It is significant to develop new aspects of the theory for design of the hyperlink processes. The separation of (A1A2&middot;&middot;&middot;At-1)/(A2A3&middot;&middot;&middot;At) is the basic configuration in the hyperlink processes differently from in conventional processes, where A1, A2, &middot;&middot;&middot;, At represent different kinds of rare earth ions with the same number of valence. The separations of two and three components have been discussed and the equations of Smin and Wmin are derived in our previous works. Nevertheless, it is still significant, especially for rare earth separations, to investigate the separations with more components. The present article will therefore focus on developing new expressions for Smin and Wmin applied to the (A1A2&middot;&middot;&middot;At﹣1)/(A2A3&middot;&middot;&middot;At) separation. Also a five-component separation case is simulated according to the derived equations. This work is an essential part of the new theory to design the hyperlink extraction processes. 展开更多
关键词 Theory of Countercurrent Extraction Minimum Amount of EXTRACTING SOLVENT Countercurrent Extraction hyperlink process Multi-Component Separation
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Minimum amount of extracting solvent of AB/BC countercurrent extraction separation using organic feed 被引量:5
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作者 程福祥 吴声 +4 位作者 张玻 刘艳 王嵩龄 廖春生 严纯华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第5期439-444,共6页
For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent (Smin) and minimum amount of scrubbing agent solution (Wmin) were discussed, and ... For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent (Smin) and minimum amount of scrubbing agent solution (Wmin) were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/BC separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/C pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic and the aqueous phase at steady state were given by computer simulation. 展开更多
关键词 rare earths countercurrent extraction hyperlink process 3-component separation
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Minimum Amount of Extracting Solvent of (A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t)) Separation When Using Non-barren Extracting Solvent 被引量:2
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作者 Fu-Xiang Cheng Sheng Wu +4 位作者 Song-Ling Wang Bo Zhang Yan Liu Chun-Sheng Liao Chun-Hua Yan 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第10期1022-1028,共7页
Hyperlink extraction technology,by virtue of its remarkable advantage of decreasing the use of chemicals in multi-component separation,has been extensively employed in rare earth separation industry in China.In hyperl... Hyperlink extraction technology,by virtue of its remarkable advantage of decreasing the use of chemicals in multi-component separation,has been extensively employed in rare earth separation industry in China.In hyperlink processes,non-barren extracting solvent and scrubbing agent solution which contain the component(s)involved in starting feed are employed in order to save both alkali for saponification and acid for scrubbing.Minimum amount of extracting solvent(denoted as S_(min))and that of scrubbing agent solution(denoted as W_(min))are important parameters to determine the consumption amounts of alkali and acid for a given countercurrent extraction separation.This article therefore discusses the influence of using non-barren extracting solvent and scrubbing agent solution on S_(min) and W_(min) of an(A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t))separation.The equations for S_(min) and W_(min) are derived,and the variation of the composition of final raffinate as well as that of final extract are determined,which will provide a valuable guidance for the design of hyperlink extraction processes of multi-component separation,such as rare earths separation. 展开更多
关键词 minimum amount of extracting solvent rare earths hyperlink process multi-component separation
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串级萃取理论发展与稀土分离工业技术进步 被引量:4
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作者 廖春生 程福祥 +1 位作者 吴声 严纯华 《中国稀土学报》 EI CAS CSCD 北大核心 2022年第6期909-919,共11页
自20世纪80年代,中国在稀土资源开采、冶炼分离和材料应用领域逐步建立了优势地位,这与中国稀土分离理论及技术的持续进步密不可分,其中关键节点事件的梳理、回顾和分析可为中国稀土科技未来发展提供借鉴。在串级萃取理论的发展历程中,... 自20世纪80年代,中国在稀土资源开采、冶炼分离和材料应用领域逐步建立了优势地位,这与中国稀土分离理论及技术的持续进步密不可分,其中关键节点事件的梳理、回顾和分析可为中国稀土科技未来发展提供借鉴。在串级萃取理论的发展历程中,最优化方程使稀土串级萃取工艺的优化设计不再无章可循,“一步放大”技术的建立大大缩短了稀土萃取分离工艺设计和参数调整周期、提高了工艺流程的灵活性,非恒定混合萃取比体系设计理论完成了对皂化、萃取、反萃取等全工序过程的模拟计算,也为重稀土萃取分离工艺的优化设计提供了指导,联动萃取分离工艺的应用使稀土分离过程的酸碱消耗显著降低,相应发展的流程设计理论解决了多组份萃取分离的理论消耗极限问题。近年来,包头混合型稀土矿转型-分离一体化工艺的工业应用获得良好经济和环保效益,进一步开展溶料-萃取-沉淀过程联动的全流程优化应存在较大降耗减排空间;中国稀土分离科技发展应规划重点解决基于过程自动控制的智能化生产和以零排放为目标的绿色化生产问题。 展开更多
关键词 串级萃取理论 一步放大 非恒定混合萃取比 联动萃取分离 全流程优化 稀土
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白云鄂博稀土矿联动萃取分离流程的经济技术指标比较 被引量:6
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作者 赵治华 姜晓丽 +3 位作者 胡刚 郑健 李俊林 王新宇 《中国稀土学报》 CAS CSCD 北大核心 2016年第1期70-76,共7页
稀土联动萃取工艺以两出口工艺为设计基础。第一模块对原料进行了预分离,第二模块充分利用了稀土元素间的交换功能,省去了第一分离段的反萃及最后分离段的皂化工序。由于其具有酸碱消耗量低、操作方便、废水产生量小等特点,近年来被越... 稀土联动萃取工艺以两出口工艺为设计基础。第一模块对原料进行了预分离,第二模块充分利用了稀土元素间的交换功能,省去了第一分离段的反萃及最后分离段的皂化工序。由于其具有酸碱消耗量低、操作方便、废水产生量小等特点,近年来被越来越多稀土分离企业所青睐。针对以氟碳铈和独居石混合矿为代表的白云鄂博稀土矿,根据生产实践经验和目前市场所需要的产品结构,提出了几种可行的P507-HCl体系联动萃取工艺流程。通过比较各联动工艺流程及传统两出口工艺流程的槽体级数、混合室容积大小、有机相和稀土存槽量、盐酸及液碱单耗、废水产生量,找出最优切割方式或联动模式,从而为白云鄂博稀土矿的联动萃取分离提供更优化工艺流程。 展开更多
关键词 白云鄂博稀土矿 联动萃取 经济技术指标 废水
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