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1、Y弘6205密級:保密期限磚幸卻童夫肇博士研究生學(xué)位論文學(xué)號:她§2塾姓名:王菱塑專業(yè):籃曼蘭籃皇熊理導(dǎo)師:整星熬援學(xué)院;籃息王捏堂院二零零六年五月十三日統(tǒng)滴水算法那樣盲目選擇正下方作為滴水方向,而是考慮水滴的先前方向以及待選擇的切分方向與水滴自身尺寸間的關(guān)系。以手寫數(shù)字為例進(jìn)行的實驗表明,該算法能夠有效克服傳統(tǒng)滴水算法進(jìn)行字符切分時由于連筆或筆畫邊緣毛刺可能帶來的誤差,提高了算法的切分正確率:關(guān)鍵詞:信息檢索文本圖像滴水算法文本分類特征選擇查詢優(yōu)化查詢擴(kuò)展相關(guān)反饋互信息RSEARCHoNSEVERALPRoBLEMSINTEXTRETRJE、後LInfo
2、rIllationRe仃ievaltecbnology(IR)aimsatrecognizinga11dacquiringinfornlation療Dmmesetofinfo肌ation,andplaysa11imporfalltr01einourstudyandsciemificrcs砌.Especiallyintoday,theIntemetisappliedmoreandmorewidely’and也equantityofinfb衄ationincreasessharply.In硒mationRetrievaltectl芏lologyhasbecom
3、eanefficient印proachforpeopletodevelopandmalceuseofallsonsofinfbmationresourcese仃ectively’toacqu沁aIldabsorbinf-0mationfleetlya11droundlyThercsearchofthepresenttheSisinvolvesinrelatedtechnologiesoninfo姍ationretrievalsuchasdocumentpmcessin舀teXtclassificationaIldqueryoptimizationetc.T
4、hefoll叭vingareac:hievedreSultsin也isdissertation:1.FeatureselectionintextclassificationInthemesis,weintroducetlleconceptsofabsolutereliability’relativereliabilityandcompositivercliabilityandsetforththefeatureselectionalgorithmbasedonmumalinfonnationreliability.ThealgO^thmcombinesth
5、econIelativitvbetweenatermandtheclassandthedif矗奠_enceonthete眥amongalltheclasses,i.e.,therelia_bilityofthemaxiummutualinfonnationamongclasses.ExperimentsshowthatcomDaredtothebasicmutua】infonnationmnction,thealgorithmbasedonmutuaJinfo啪ationreliabilitycanimpmvetheprecision,recallandF
6、lmeasuresefrectively.Furthermorc,wealso印plynomalizationtosevaltraditional向nctionsormaI∞10calfbatureselectionbasedonthese矗Inctions.ExDerimentsshowthatnonnalizedf.canlreselectionandlocalf色atureselectioncanimDrovetheclassificationprecisionmoreorless.2.MuticlassclassificationItiscommo
7、ntosetathresholdforeachclassinordertosettletheproblemthatatcxtmaybelOngtodi腩rentclasses.WhenthesimilarityofthetextandoneclassisdbOvetbethresholdofthisclass.th即thetextisclassifiedtothisclass.1nthismcsis,、veresearchonthedetenninationofthresh01d,putfonvardthethresholddetemlinationalg
8、orithmbasedonthemaximizedevaluati