简介:UE-Bézier(unifiedandextendedBézier)basisistheunifiedformofBézier-likebases,includingpolynomialBézierbasis,trigonometricpolynomialandhyperbolicpolynomialBézierbasis.SimilartotheoriginalBézier-likebases,UE-Bézierbasisfunctionsarenotorthogonal.Inthispaper,agroupoforthogonalbasisisconstructedbasedonUE-Bézierbasis.ThetransformationmatricesbetweenUE-Bézierbasisandtheproposedorthogonalbasisarealsosolved.
简介:Inthispaper,thesmoothconnectionbetweentwoB-splinesurfacesisdiscussed.First,abriefproofofsomesimplesufficientconditionsofG~0andG~1continuityisgiven.Onthisbasis,anovelmethodforG~0orG~1connectionbetweentwoadjacentB-splinesurfacesispresented.Areparameterizationstepisfirstlytakenforoneofthesurfacessuchthattheyhavethesameparameterizationinvdirection,then,adjusttheirboundarycontrolverticestomakethemG~0orG~1connected.TheG~1connectionparameterisdeterminedbyanoptimizationproblem.Comparedwiththeexistedmethods,ourmethodissimpleandeasytobeusedinpractice.
简介:Itisaresearchsubjectincomputervisionto3Dreconstructionofanobjectrepresentedbyasingle2Dlinedrawing.Previousworkson3Dreconstructionfrom2Dlinedrawingsfocusonobjectswithlines,plane,view,andsoon.Thispapermainlystudiesthe3Dreconstructionfrom2Dlinedrawings.Besides,anewapproachisproposed:itisthatfortheresearchofthepointcoordinatesof2Dlinedrawings,soastoachievetheobjectreconstructionbythereconstructionofpointcoordinates.Thereconstructionprocessincludes:①thecollectionofpointcoordinates(X,Y)of2Dlinedrawings;②thederivationofmathematicalformulaaboutthereconstructionofthepointof2Dlinedrawings,andcalculatingthecorrespondingpointofthe3Dcoordinates;③theregenerationof3Dgraphicswith3Dpoints;④analyzeerrorbytheproportionalofparallelofaxonometricprojection,inordertoprovetheaccuracyofthemethod.
简介:针对宁波工程学院数据库理论与技术重点课程的建设,介绍2C+E人才培养体系,提出本课程在核心专业知识、核心专业能力、工程环境建设等方面的一些改革措施,并指出课程今后的建设方向。