简介:PARAMETRICSURFACE/SURFACEINTERSECTIONZengXianglin;WangQifu;ZhouJi;YuJunPARAMETRICSURFACE/SURFACEINTERSECTION¥ZengXianglin;Wan...
简介:Inthispaper,theproblemoffindingtheintersectionofatriangularBezierpatchandaplaneisstudied.Forthedegreethatonefrequentlyencountersinpractice,i.e.n=2,3,anefficientandreliablealgorithmisobtained,andcomputationalstepsarepresented.
简介:ANINTERSECTIONPROPERTYOFTHESIMPLERANDOMWALKSINZ ̄dZHOUXIANYIN(DepartmentofMathematics,BeijingNormalUniversity100875,China)Abst...
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简介:对线线的描述拓扑的关系尽管许多努力被做了,仍然是一个未解决的问题。这个问题涉及象空间质问,空间分析和制图综合那样的许多实际应用。开发一条健全、有效的途径描述线线关系,它是第一必要排队定义一个个人的拓扑学,即,本地拓扑学。连接的度的概念在一根线的几何结构被用于拓扑的差别的鉴定。一根线的一般拓扑的定义被给,即,端点集合和内部点设定。这个定义能被用于不同尺寸的嵌入的空格,合作尺寸是否等于或比零大。在这个基础上,打电话给4intersection-and-difference的一个通用模型为对基本线线的描述被建立拓扑的关系,一张概念的邻居图与拓扑的距离的考虑在之上被造。建议模型能在/R~1和/R~2代表在线片断之间的拓扑的变化,和基本关系的性质,这被结束。
简介:WepresentaparalleliterativealgorithmtofindtheshortestdistanceprojectionofagivenpointontotheintersectionofafinitenumberofclosedconvexsetsinarealHilbertspace;thenumberofsetsusedateachiterationsteptcorrespondingtothenumberofavailableprocessors,maybesmallerthanthetotalnumberofsets.TherelaxationcoefficientateachiterationstepisdeterminedbyageometricalconditioninanassociatedHilbertspace,whilefortheweightsmildconditionsaregiventoassurenormconvergenceoftheresultingsequence.Thesemildconditionsleaveenoughflexibilitytodeterminetheweightsmorespecificallyinordertoimprovethespeedofconvergence.
简介:Detectinganddescribingmovementofvehiclesinestablishedtransportationinfrastructuresisanimportanttask.Ithelpstopredictperiodicaltrafficpatternsforoptimizingtrafficregulationsandextendingthefunctionsofestablishedtransportationinfrastructures.Thedetectionoftrafficpatternsconsistsnotonlyofanalysesofarrangementpatternsofmultiplevehicletrajectories,butalsooftheinspectionoftheembeddedgeographicalcontext.Inthispaper,weintroduceamethodforintersectingvehicletrajectoriesandextractingtheirintersectionpointsforselectedrushhoursinurbanenvironments.Thosevehicletrajectoryintersectionpoints(TIP)arefrequentlyvisitedlocationswithinurbanroadnetworksandaresubsequentlyformedintodensity-connectedclusters,whicharethenrepresentedaspolygons.Forrepresentingtemporalvariationsofthecreatedpolygons,weenrichthesewithvehicletrajectoriesofothertimesofthedayandadditionalroadnetworkinformation.Inacasestudy,wetestourapproachonmassivetaxiFloatingCarData(FCD)fromShanghaiandroadnetworkdatafromtheOpenStreetMap(OSM)project.ThefirsttestresultsshowstrongcorrelationswithperiodicaltrafficeventsinShanghai.Basedontheseresults,wereasonouttheusefulnessofpolygonsrepresentingfrequentlyvisitedlocationsforanalysesinurbanplanningandtrafficengineering.
简介:AstatisticalanalysisonearthquakeactivityintheKashi-WuqiaintersectionareatriggeredbyearthtideisdonebySchusterstestandthePermutationtestondailyandmonthlyscales.Thenorth-south,east-westcomponentofthetidalforceandtidalbodystressarechosenasthetidalcurveinthedailyscale.Theresultsshowthatmostoftheearthquakesoccurrednearthemaximum0°ofthethreekindsoftidalcurves,thepredominanttidalphasesoftheearthquakeare-5.86°,6.60°and-15.52°,andthefrequencyoftheearthquakesincreaseswiththeincreaseofthetide;withthreekindsoftidalcurves(thenorth-south,east-westcomponentofthetidalforceandtidalbodystress),thepSofSchusterstestforalltheearthquakesis10.52%,2.40%and2.06%,andthepPofthePermutationtestis10.90%,2.40%and2.06%,andtheresultsofpSandpPbasedontheeast-westcomponentofthetidalforceandtidalbodystressarebelowthethresholdof0.05thattidaltriggeringofearthquakes.Inthemonthlyscale,boththepSandpPareverylow(closeto0),farbelowthethresholdof0.05oftidaltriggeringofearthquakes,andthepredominanttidalphaseforearthquaketriggeringis-18.95°,closetothemaximum0°(newmoonandfullmoon)oftheearthtideinmonthlyscale.Regardingthestatisticaltestresultoftidaltriggeringofearthquakes,apreliminaryexplanationisgivenastowhythetriggereffectintheeast-westdirectionisgreaterthanthatinnorth-southdirection.
简介:ConstraintsfromP-Tpseudosections(MnNCKFMASHsystem),foliationintersection/inflectionaxespreservedinporphyroblasts(FIAs),mineralassemblagesandtexturalrelationshipsforrockscontainingallthreeAl2SiO5polymorphsindicateakyanite→andalusite→sillimanitesequentialformationatdifferenttimesratherthanstablecoexistenceattheAl2SiO5triplepoint.AllthreeAl2SiO5polymorphsgrewintheChl,Bt,Ms,Grt,St,PlandCrdbearingOrdovicianClayholeSchistinBalcooma,northeasternAustraliaseparatelyalongaloopedP-T-t-Dpaththatswapsfromclockwisetoanticlockwiseinthetectono-metamorphichistoryoftheregion.KyanitegrewduringcrustalthickeninginanEarlySilurianOrogeniceventfollowedbydecompression/heating,andalusiteandfibroliticsillimanitegrowthduringEarlyDevonianexhumation.