Báo cáo khoa học: "PCFGs, Topic Models, Adaptor Grammars and Learning Topical Collocations and the Structure of Proper Names" ppt

... for Computational LinguisticsPCFGs, Topic Models, Adaptor Grammars and Learning Topical Collocations and the Structure of Proper NamesMark JohnsonDepartment of ComputingMacquarie Universitymjohnson@science.mq.edu.auAbstractThis ... labelled X and whose ith child is a member of TBi.1149 The set of trees generated by the CFG is TS,where S is the start symbol, and the set of stringsgenerated by the CFG is the set of yields ... Topic iindicate the topics as-signed to particular words, and the local trees ex-panding Docjto Topic i(one per word in the docu-ment) indicate the distribution of topics in the doc-ument. The corresponding...

Báo cáo khoa học: "Employing Topic Models for Pattern-based Semantic Class Discovery" doc

... Proceedings of the 47th Annual Meeting of the ACL and the 4th IJCNLP of the AFNLP, pages 459–467,Suntec, Singapore, 2-7 August 2009.c2009 ACL and AFNLPEmploying Topic Models for Pattern-based ... Determine the number of topics: Most topic models require the number of topics to be known beforehand1. However, it is not an easy task to automatically determine the exact number of se-mantic ... i, and ki being the number of RASCs corresponding to site i. To determine the weight of every type of pattern, we randomly selected 50 RASCs for each pattern and labeled their quality. The...

Báo cáo khoa học: "Smaller Alignment Models for Better Translations: Unsupervised Word Alignment with the 0" potx

... (1) The parameters of these models are the distortionprobabilities d(aj| aj−1, j) and the translation prob-abilities t( fj| eaj). The three models diﬀer in theirestimation of d, but the ... concern ushere. All three models, as well as IBM Models 3–5,share the same t. For further details of these models, the reader is referred to the original papers describ-ing them (Brown et al., 1993; ... 1996).Let θ stand for all the parameters of the model. The standard training procedure is to ﬁnd the param-eter values that maximize the likelihood, or, equiv-alently, minimize the negative...

Báo cáo khoa học: "Typed Graph Models for Semi-Supervised Learning of Name Ethnicity" pptx

... – 32BACKOFF, 43BACKOFF,45BACKOFF, and POSITION – and four corre-sponding parameters to be estimated.Combined graphFinally, we consider the union of the character n-gram graph and the FirstName-LastName ... the previous case, a typed edge (32BACK-OFF) is added between the trigram aba and the bi-gram ab representing the backoff relation. In the absence of these edges between features, our graphwould ... mos-BEG connectedto the position-independent trigram mos using the typed edge POSITION. Further, the trigram mosis connected to the bigrams mo and os usinga 32BACKOFF edge. The resulting graph...

Tài liệu Báo cáo khoa học: A novel coupled enzyme assay reveals an enzyme responsible for the deamination of a chemically unstable intermediate in the metabolic pathway of 4-amino-3-hydroxybenzoic acid inBordetellasp. strain 10d doc

... analysis, and the determination of released ammonia. The coupled enzymeassay revealed the mechanism of the deamination reaction and the subsequent metabolism, including the deaminationstep. The product ... time. The peak at 268 nm was assigned to2,5-pyridinedicarboxylic acid based on the wavelength [10].Purification and properties of the purified enzyme The activity of the enzyme present in the crude ... (A) the fluorescence excitation spe ctrum (detect ed at 530 nm) and ( B) the emission spe ctrum (excited at 450 n m) of the supernatant of the heat-treated enzyme (1.2 mg protein per mL). The cofactor...

Báo cáo khoa học: A novel metallobridged bis(b-cyclodextrin)s ﬂuorescent probe for the determination of glutathione doc

... ⁄ 480 nm. The GSH content of the plasma was derived from the standard curve and the regression equation. The average recovery test was made using the standardaddition method, and the RSD was ... reagentblanks, and S is the slope of the standard curve. The relative standard deviation was 2.5%, obtained from aseries of 11 standards each containing 2.00 lm GSH.When the concentration of GSH exceeded ... ions and twonaphthyl ﬂuorophores. The compound could be dis-solved in aqueous solution and showed high bindingability because of the two adjacent bis(b-CD)s.Because of the conformation of the...

Báo cáo khoa học: "PARALLEL MULTIPLE CONTEXT-FREE GRAMMARS, FINITE-STATE TRANSLATION SYSTEMS, AND POLYNOMIAL-TIME RECOGNIZABLE SUBCLASSES OF LEXICAL-FUNCTIONAL GRAMMARS" docx

... of a derivation tree is a finite set F of pairs of at- tribute names and their values. F is called the f- structure of v. An lfg G consists of a cfg Go called the underlying cfg of G and ... dc-lfg G, for each pair (tl, t2) of derivation trees in G, if the f -structure and nonterminal of the root of tl are the same as those of t2, then t] and t2 derive the same termi- nal string. Let ... distinct. There exist a derivation tree t and a subset of nodes V = {v],v2, ,v,~} of t such that the label ofvi is Ai (1 < i < n) and the f- structures of vi's are the same...

Báo cáo khoa học: Cofactor-independent oxygenation reactions catalyzed by soluble methane monooxygenase at the surface of a modiﬁed gold electrode pot

... necessary, the solution contacting the electrodes was ventilated bymeans of a stream of air from an electric fan. The effect of the substrate methane on the electrochemical properties of the MMOH/MMOB/catalase ... investigate the effects of catalase, MMOB and MMOBtru and the substrate acetonitrile on electrontransfer to MMOH was also performed between 0 and )0.6 V, at the scan speed and protein and substrateconcentrations ... Fig. 2 and then cycled from 0to )0.6 V at 2 mVÆs)1. The arrow shows the eﬀect of increasingcatalase concentrations (0, 2.4, 4.8 and 7.2 lM, respectively). The eﬀect of ventilating the reaction...

Báo cáo khoa học: "Adding Syntax to Dynamic Programming for Aligning Comparable Texts for the Generation of Paraphrases" potx

... (Milan Theater) and is not at the beginning of that constituent. Finally, the syntactic depen-dence trace of a word is the path of IOB valuesfrom the root of the tree to the word itself. The last ... po-sitions the primary focus on the quality of para-phrases and/ or translations, we are more interestedin the relation between the use of syntactic fea-tures and the correctness of the sentences ... down the cumulative score by the lengthdifference between the two traces. Such ﬁnal scoreis named the trace-score of the two words.We declare “unmatched” if the sum of the IOB-score and the...

Báo cáo khoa học: ISC1-encoded inositol phosphosphingolipid phospholipase C is involved in Na+/Li+ halotolerance of Saccharomyces cerevisiae pptx

... mediates Na+ and Li+ionextrusion from the cell. We therefore investigated whether the loss of halotolerance in isc1D cells was due to the failure of ENA1 induction in the mutant. For this, the ENA1-lacZpromoter–reporter ... induction of the ENA1/PMR2 gene(designated as ENA1 in the following) encoding an enzyme of the P-type ATPase family. This cation-extrusion pumppromotes the efﬂux of Na+ and Li+from the cell. ... ISC1-defective and isogenic wild-type cells. The failure of ENA1 induction in the ISC1 mutant wasnot absolute but  60% of the wild-type reporter activity.These ﬁndings agree with the known complexity of...

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