简介:2.3 VB访问数据库的方法 VB访问数据库的方法很多,而ODBC接口并不是VB访问数据库运行效率最高的方法,因此ADO通过其内部的属性和方法提供统一的数据访问接口方法
简介:AnelectromagnetdesignsystemisdevelopedusingVisualC++languageandOpenGLtechnologytovisualizeparametric3Dmodel.Thesystemconsistsofprimarydesign,optimizationdesign,dynamicandstaticcharacteristics,andvisualsimulation.Allempiricalparametersandcurvesusedindesignprocessarestoredindatabase.Throughhuman-computerinteractions,anelectromagneticsystemcanbedesignedconvenientlywiththeresultsandcharacteristicscurvesdisplayedingraphicmodel.Usingthissystemcangreatlyshortentheprocessofproductdesign,andtheresultssatisfytechnicalrequirements.
简介:Thetheoreticalframeworkofvisualsimulationinvirtualrealityisdiscussed.Thenewconceptofvisualimagespaceissupposed.Onthebasisofvisualimagespace,invisualperceptivesense,VRisconsideredasaspatialsimulation.Theobjectiveofthespatialsimulationistotransformphysicalspacetovisualimagespace.Last,theprototypesystem,surveying&mappingvirtualReality(SMVR),isdeveloped,andthespacesimulationaboveisrealized.ByuseofSMVR,thereal3Drepresentation,3Dvisualanalysis,virtualplananddesignscanbeimplemented.
简介:Watermarkingisatechniqueforlabelingdigitalpicturesbyhidingsecretinformationintoimages.Watermarkembeddingisamethodtodiscourageunauthorizedcopyingandidentifytheownerordistributorofdigitaldata.Inthispaper,anewmethodisproposed.Thewatermarkisprocessedasavisuallyrecognizablepattern-binaryimage,whichincludesmoreinformationthanthetraditionalsymbolorIDnumberandis"extracted"insteadofonly"detected"tocharacterizetheowner.Thewatermarkishiddeninthehostimagebyselectivelymodifyingthemiddle-frequencypartofthehostimageinconjunctionwiththehumanvisualsystem(HVS)andtheimagediscretecosinetransform(DCT).Theexperimentalresultsshowthatthismethodcansurviveimagecroppingandimagecompression,andgetbetterresults,thisisalsoaprospectivemethod.