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简介：Formanyclusteringalgorithms,itisveryimportanttodetermineanappropriatenumberofclusters,whichiscalledclustervalidityproblem.Inthispaper,anewclusteringvalidityassessmentindexisproposedbasedonanovelmethodtoselectthemarginpointbetweentwoclustersforin-ter-clustersimilaritymoreaccurately,andprovidesanimprovedscatterfunctionforintra-clustersimilarity.Simulationresultsshowtheeffectivenessoftheproposedindexonthedatasetsunderconsiderationregardlessofthechoiceofaclusteringalgorithm.

简介：Thepapermakesastudyonsixparts,namely,speaking,writing,sentence,cloze,readingandlisteninginanEnglishtestwithstudentsattwodifferentproficiencylevels.Theirscoredatawerestudiedthroughreliabilityanalysis,validityanalysis,factoranalysisandanalysisofvariance(ANOVA)toconductthevalidationofthisEnglishtest.Thepapertriestoexplorethescoredatainternalconsistency,groupdifferencerecognitiontomaintaintheobjectivityandaccuracyinEnglishtests.

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简介：它的接触角度(CA)上的考虑固体的可湿的性质能用古典Wenzel和Cassie的方程理论上被分析。然而，对超级恐水病的表面的最近的强烈兴趣要求了二个方程的适用性的复试。我们报导热力学的分析特别地，决定普遍性二个方程的限制。用一些特殊表面，我们证明二个方程为微规模的异构的结构是有效的，然而，他们为宏规模是有病的异构的表面。而且，现在的计算建议基本热力学的分析是最强大、可靠的途径为各种各样的在结构上决定全面wettability有图案的表面。

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简介：Background：TheGlobalPhysicalActivityQuestionnaire（GPAQ）hasbeenusedtomeasurephysicalactivity（PA）andsedentarytimeinFrance,butnostudyhasassesseditspsychometricproperties.ThisstudyaimedtocomparethereliabilityaswellascriterionandconcurrentvalidityoftheFrenchversionoftheGPAQwiththeFrenchInternationalPhysicalActivityQuestionnairelongform（IPAQ-LF）anduseofanaccelerometerinageneraladultpopulation.Methods：Weincluded92participants（studentsorstaff）fromtheMedicineCampusattheUniversityofLorraine,Nancy（north-easternFrance）.TheFrenchGPAQwascompletedtwice,7daysapart,tostudytest-retestreliability.TheIPAQ-LFwasusedtoassessconcurrentvalidityoftheGPAQ,andparticipantsworeanaccelerometer（ActiGraphGT3X＋）for7daystostudycriterionvalidity.ReliabilityaswellasconcurrentandcriterionvalidityoftheGPAQweretestedbytheintraclasscorrelationcoefficient（ICC）,Spearmancorrelationcoefficientforquantitativevariables,andKappaandPhicoefficientsforqualitativevariables.BothconcurrentandcriterionvalidityofGPAQwereassessedbyBland-Altmanplots.Results：TheGPAQshowedpoortogoodreliability（ICC=0.37-0.94;Kappa=0.50-0.62）andconcurrentvalidity（Spearmanr=0.41-0.86）,butonlypoorcriterionvalidity（Spearmanr=-0.22-0.42）.LimitsofagreementfortheGPAQandaccelerometerwerewide,withdifferencesbetween286.5min/weekand601.3min/week.Conclusion：TheFrenchversionoftheGPAQprovideslimitedbutacceptablereliabilityandvalidityforthemeasurementofPAandsedentarytime.ItmaybeusedforassessingPAandsedentarytimeinaFrenchadultpopulation.

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简介：TheCET4writingtestiswidelyusedinChina,butwhetheritisamorereliableandvalidtestofwritingforCET4thanothermethodsofevaluationisstillnotclear.Thepurposeofthisstudywastoexaminethereliabilityandthevalidityofamodificationofthistest.Incarryingoutthestudy,atotalof60Band4studentsinZhejiangUniversitytookthemodifiedtest,aCET4testandaFirstCertificatePracticeTest.TheresultsofthisstudydemonstratethatthemodifiedversionisasignificantlymorereliableandvalidwritingtestthanthepresentCET4writingtest.TheseresultssuggestthattheCET4writingtestneedsmodification.

简介：Dataenvelopmentanalysis(DEA)modeliswidelyusedtoevaluatetherelativeefficiencyofproducers.Itisakindofobjectivedecisionmethodwithmultipleindexes.However,thetwobasicmodelsfrequentlyusedatpresent,theC2RmodelandtheC2GS2modelhavelimitationswhenusedalone,resultinginevaluationsthatareoftenunsatisfactory.Inordertosolvethisproblem,amixedDEAmodelisbuiltandisusedtoevaluatethevalidityofthebusinessefficiencyoflistedcompanies.AnexplanationofhowtousethismixedDEAmodelisofferedanditsfeasibilityisverified.

简介：Background:Wearablemonitors（WMs）areusedtoestimatethetimespentinsedentarybehaviors（SBs）andlight-intensityphysicalactivities（LPAs）andtheirassociatedenergycost;however,theaccuracyofWMsinmeasuringbehaviorsonthelowerendoftheintensityspectrumisunclear.Theaimofthisstudywastoassessthevalidityof3WMs（ActiGraphGT3X+;activPAL,andSenseWear2）inestimatingtheintensityofSBandLPAinadultsascomparedwiththecriterionmeasureofoxygenuptake（VO2）measuredbyindirectcalorimetry.Methods:Sixteenparticipants（age:25.38±8.58years）woretheActiGraphGT3X+,activPAL,andSenseWear2devicesduring7sedentary-to-lightactivities.VO2（mL/kg/min）wasestimatedbymeansofaportablegasanalyzer,OxyconMobile（Carefusion,YorbaLinda,CA,USA）.Alldataweretransformedintometabolicequivalentsandanalyzedusingmeanpercentageerror,equivalenceplots,Bland-Altmanplots,kappastatistics,andsensitivity/specificity.Results:MeanpercentageerrorwaslowestfortheactivPALforSB（14.9%）andLPA（9.3%）comparedwithotherWMs,whichwere>21.2%.NoneoftheWMsfellwithintheequivalencyrangeof±10%ofthecriterionmeanvalue.Bland-AltmanplotsrevealednarrowerlevelsofagreementwithallWMsforSBthanforLPA.KappastatisticswerelowforallWMs,andsensitivityandspecificityvariedbyWMtype.Conclusion:NoneoftheWMstestedinthisstudywereequivalentwiththecriterionmeasure（VO2）inestimatingsedentary-to-lightactivities;however,theactivPALhadgreateroverallaccuracyinmeasuringSBandLPAthandidtheActiGraphandSenseWear2monitors.

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简介：TheusualF--testhasbeenusedtotestagenerallinearhypothesisforatwo--stageleastsquaresmethodinasystemofeconomicequations.However,wefindthatthisF--testisactuallyasymptoticallyinvalid.Somesuggestionsaregivenfortestingagenerallinearhypothesisinthissituation.

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