Báo cáo khoa học: "Selecting Query Term Alterations for Web Search by Exploiting Query Contexts" pptx

... 148–155, Columbus, Ohio, USA, June 2008. c 2008 Association for Computational Linguistics Selecting Query Term Alterations for Web Search by Exploiting Query Contexts Guihong Cao Stephen Robertson Jian-Yun ... Abstract Query expansion by word alterations (alterna- tive forms of a word) is often used in Web search to replace word stemming. This allows users...

Ngày tải lên: 17/03/2014, 02:20

... all possible trees in a shared-forest structure (Langkilde, 2000). The forest structure is represented by an AND-OR tree, and it con- tains many tree structures. The forest represen- tation saves ... each terminal in the parse tree of the original sentence is marked if it exists in the compressed sentence. In the figure, the marked terminals are represented by circles. Second, each non-ter...

Ngày tải lên: 20/02/2014, 12:20

... Intermediate data structure after unify- ing A 1 with [~. Disjunction is expressed by non- determinism when applying the dependency func- tions. When we unify a feature structure segment for ... We therefore unify 5z with the feature structure tagged as [~] in Figure 5. Disjunction is expressed by non-determinism when applying the dependency functions. Fig- ure 7 shows the inter...

Ngày tải lên: 17/03/2014, 07:20

... offers new possibilities for the study of such complexes, providing direct e vidence for their f ormation and an accurate determination of their binding stoichiometry. For instance, in the field ... 1, v/v) acidified with 1% (v/v) formic acid. The f ollowing molecular masses were measured: 29 930 ± 1.8 Da for RARa;26735±2.3Da for RXRa with deletion of the N-terminal methionine and 26...

Ngày tải lên: 23/03/2014, 13:20

... activated by number of hormones, neurotransmitters and odorants and are coded for by a family or almost 1000 genes in humans. Similarly, several genes for G proteins exist and these code for 20 ... G protein a subunits, which provide the primary determinant for ‘information flow’ from the activated GPCR are grouped into four families: Gs (for stimulatory), which activates adenyly...

Ngày tải lên: 30/03/2014, 10:20

... most important query types they are interested in. 2 More information on XQuery is available at www.w3.org/TR/xquery/. 248 Generate Query Save Search! -TRACT (XQuery For Atroixt) X- TRACT (XQuery for ... improved in average by 2% (resulting in 98% for the top ranked terms) by adding term variation recognition. 4.3 Term clustering A cluster of terms is a group of related...

Ngày tải lên: 08/03/2014, 21:20

... interpret by humans. We show that for certain domains, the frequency with which terms appear in a corpus on their own and in conjunction with other terms induces a nat- ural taxonomy. We formally ... process. 3 Term- frequency-induced Taxonomies For some application domains, a taxonomy is in- duced by the frequency in which terms appear in a corpus on their own and in combination wit...

Ngày tải lên: 20/02/2014, 04:20

... clustering solutions for all values of k from 1 N , and then determines the mean and standard deviation of the criterion function. Then, a score is computed for each value of k by sub- tracting the ... We present a methodol- ogy that automatically selects an appropriate value for k. Our strategy is to perform clustering for suc- cessive values of k, and evaluate the resulting solu-...

Ngày tải lên: 22/02/2014, 02:20

... ap- proaches realize it by referring to query expan- sion or relevance feedback. Terms that are se- mantically equivalent to the query terms or co- occurred with the query terms frequently can be ... happen among any set of query terms, hence the assump- tion of dependence occurring among any query terms is considered more reasonable. The dependences among all query terms wil...

Ngày tải lên: 08/03/2014, 02:21

... incubation for 72 h in the presence of inhibitors, the cells were analyzed by FACS for GFP expression. Propidium iodide staining was used to gate for live cells. In each sample we gated for the ... and 12 from pCDNA3.1/PS1 DE9 with an N-terminal flag sequence (kindly provided by F. Reinhard) and was cloned into pIRESpuro2. We thereby removed the N-terminal flag sequence. The last th...

Ngày tải lên: 08/03/2014, 08:20