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Agricultural Market Name Geo-Locating System Based on an Administrative Ontology and Web Search Engine

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Journal of Integrative Agriculture 2012年第5期11卷 849-857页

作者： HU Yi-min SONG Liang-tu wei yuan-yuan HUANG He WANG Xue Institute of lntelligent Machines Chinese Academy of Sciences Hefei 230031 P.R.China School of Information Science and Teehnology University of Science and Technology of China Hefei 230026 P.R.China

The problem of associating the agricultural market names on web sites with their locations is essential for geographical analysis of the agricultural products. In this paper, an algorithm which employs the administrative ontology and the statistics from the search results were proposed. The experiments with 100 market names collected from web sites were conducted. The experimental results demonstrate that the algorithm proposed obtains satisfactory performance in resolving the problem above, thus the effectiveness of the method is verified.

关键词： agriculture markets geo-locating ontology search engine Pearson's chi-square test

Structured AJAX Data Extraction Based on Agricultural Ontology

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Journal of Integrative Agriculture 2012年第5期11卷 784-791页

作者： LI Chuan-xi SU Ya-ru WANG Ru-jing wei yuan-yuan HUANG He Institute oflntelligent Machines Chinese Academy of Sciences Hefei 230031 P.R.China School of Information Science and Technology University of Science and Technology of China Hefei 230026 P.R.China

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.

关键词： information extraction structured data AJAX agricultural ontology semantic annotation

Agricultural Ontology Based Feature Optimization for Agricultural Text Clustering

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Journal of Integrative Agriculture 2012年第5期11卷 752-759页

作者： SU Ya-ru WANG Ru-jing CHEN Peng wei yuan-yuan LI Chuan-xi HU Yi-min Institute of Intelligent Machines Chinese Academy of Sciences Hefei 230031 P.R.China School of Information Science and Technology University of Science and Technology of China Hefei 230026 P.R.China

Feature optimization is important to agricultural text mining. Usually, the vector space model is used to represent text documents. However, this basic approach still suffers from two drawbacks： thecurse of dimension and the lack of semantic information. In this paper, a novel ontology-based feature optimization method for agricultural text was proposed. First, terms of vector space model were mapped into concepts of agricultural ontology, which concept frequency weights are computed statistically by term frequency weights; second, weights of concept similarity were assigned to the concept features according to the structure of the agricultural ontology. By combining feature frequency weights and feature similarity weights based on the agricultural ontology, the dimensionality of feature space can be reduced drastically. Moreover, the semantic information can be incorporated into this method. The results showed that this method yields a significant improvement on agricultural text clustering by the feature optimization.

关键词： agricultural ontology feature optimization agricultural text clustering

Experimental study on the through-thickness properties of structural steel thick plate and its heat-affected zone at low temperatures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第3期16卷 217-228页

作者： yuan-qing WANG Xiao-wei LIAO yuan-yuan ZHANG Yong-jiu SHI Key laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil Engineering Tsinghua University Beijing 100084 China

Lamellar tearing and crack-induced brittle failures along steel plates in the through-thickness direction seriously threaten the safety and reliability of steel thick plate structures in construction and service, especially at low ambient temperatures. Three kinds of tests, including uniaxial tensile tests, Charpy V-Notch impact tests, and three-point bending （TPB） tests were performed at normal and low temperatures to investigate the through-thickness mechanical properties, impact and fraclure toughness of Q345B structural steel plates with thicknesses from 60 to 165 mm. The test specimens were mainly sampled along the through-thickness direction of the plate, but transverse specimens along the rolling direction were also involved. The ductility index （percentage reduction of area）, impact toughness index （Charpy impact energy）, and fracture toughness index （critical crack tip opening displacement （CTOD） values） all decrease as the temperature declines. All the mechanical properties and the impact and fracture toughness along the through-thickness direction are worse than those along the rolling direction. The results also offer experimental support for the determination of an evaluation indicator for structural steel thick plates with through-thickness characteristics.

关键词： Structural steel thick plate Through-thickness properties Mechanical properties Impact toughness Fracturetoughness Low temperature

Studies on sulfinatodehalogenation ⅫⅠ.Synthesis of 2-perfluoroalkyl-2-deoxy-D-glucose,mono- and poly-O-polyfluoroalkylated-D-glucoses

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Chinese Journal of Chemistry 1991年第4期9卷 351-359页

作者： HUANG,wei-yuan XIE,yuan Shanghai Institute of Organic Chemistry,Academia Sinica,Shanghai 200032

The reaction of perfluoroalkyl iodide or perfluoroalkyl bromide with sulfite radical anion (SO_3^-)generated from sodium bisulfite/potassium ferricyanide in water/DMF at 70—75°C gave the corresponding perfluoroalkanesulfinate ia good ***,it was shown that the reagent system can also initiate the addition of perfluoroalkyl iodide to olefins or alkynes at 50—65℃.

关键词： Synthesis of 2-perfluoroalkyl-2-deoxy-D-glucose,mono and poly-O-polyfluoroalkylated-D-glucoses Studies on sulfinatodehalogenation

Studies on the reaction of cupric(Ⅱ)perfluoroalkanesulfinate

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Chinese Journal of Chemistry 1990年第3期8卷 259-264页

作者： HUANG,wei-yuan XIE,yuan Shanghai Institute of Organic Chemistry,Academia Sinica,Shanghai 200032

Reaction of aqueous solution of sodium perfluoroalkanesulfinate with cupric sulphate gave a high yield of cupric perfluoroalkanesulfinate,which decomposed slowly in the air on exposure to light to give perfluorocarboxylic *** reaction between cupric perfluoroalkanesulfinate and olefins in the presence of potassium iodide and excess CuSO_4 in ether at low temperature(-30 to-20℃)for- med two kinds of adducts,namely the normal adducts,R_fSO_2CH_2CHIR(2)and the adducts resulting from the loss of SO_2 moiety,R_f CH_2CHIR(3)in yields ranging from morderate to *** results were identical with that of the addition of perfluoroalkanesulfonyl iodide to olefins.A radical reac- tion mechanism is proposed.

关键词： CI Studies on the reaction of cupric perfluoroalkanesulfinate

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响应矩阵分析方法在BEPC储存环上的应用

高能物理与核物理 2006年第z1期30卷 43-45页

作者：魏源源秦庆中国科学院高能物理研究所北京100049

由于储存环中各种元件误差的存在,机器的实际运行模式与设计模式有一定的偏差．目前广泛开展的响应矩阵方法研究,可以分析出磁铁元件以及束流位置测量元件的误差,使束流基本参数得到校正．介绍了用响应矩阵分析方法,在BEPC储存环上进行... 详细信息

由于储存环中各种元件误差的存在,机器的实际运行模式与设计模式有一定的偏差．目前广泛开展的响应矩阵方法研究,可以分析出磁铁元件以及束流位置测量元件的误差,使束流基本参数得到校正．介绍了用响应矩阵分析方法,在BEPC储存环上进行的局部轨道校正的实验研究,以及BEPC储存环束流参数校正的模拟研究．

关键词：响应矩阵闭轨畸变束流参数校正

PERFLUOROALKANESULFONYL IODIDE GENERATED FROM THE REACTION OF PERFLUOROALKANESULFINATE SALT WITH IC1

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Chinese Chemical Letters 1990年第2期1卷 165-166页

作者： wei yuan HUANG yuan XIE Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai,200032

The reaction between perfluoroalkanesulfinate salts(1)[R_fSO_2M R_f=a,Cl(CF_2)_4;b,Cl(CF_2)_6;c,Cl(CF_2)8;d,n-C_6F_(13);e,n-C_8F_(17);M-Na;K; Hg(I)]and iodine monochloride in dichloromethane at low temperature(e.g. -30--50℃)resulted in the formation of the corresponding perfluoroalkane- sulfonyl iodides(2),which were identified by their 19_F NMR *** perfluoroalkanesulfonyl iodides generated in situ reacted smoothly with olefins to forum 1:1 adducts with good ***,these reactions provide another method for the synthesis of the very unstable perfluoroalkanesulfonyl iodide.

关键词： Li Cl CF PERFLUOROALKANESULFONYL IODIDE GENERATED FROM THE REACTION OF PERFLUOROALKANESULFINATE SALT WITH IC1 IC

The Reaction of Sodium Perfluoroalkanesulfinate with PCl_3

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Chinese Chemical Letters 1990年第1期1卷 27-28页

作者： wei yuan HUANG yuan XIE Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai,200032,China

The reaction between sodium perfluoroalkanesulfinate(1)(Rf=a,Cl(CF_2)_4;b, Cl(CF_2)_6;c,Cl(CF_2)_8;d,n-C_6F_(13);e,n-C_8F_(17);f,H(CF_2)_4OCF_2CF_2)and phosphorus trichloride in acetonitrile at 0℃ resulted in the formation of an unstable intermediate,which was hydrolysed directly with aqueous sodium hydro- xide solution to give the corresponding perfluorocarboxylic acid in good yield.

关键词： CF The Reaction of Sodium Perfluoroalkanesulfinate with PCl3 Cl PCI