简介：Inthispaper,analgorithmthatdeterminesarealalgebraiccurveisoutlined.Itsbasicstepistodividetheplaneintosubdomain1sthatincludeonlysimplebranchesofthealgebraiccurvewithoutsingularpoints.Eachofthebranchesisthenstablyandefficientlytracedintheparticularsubdomain.Exceptfortracing,thealgorithmrequiresonlyacoupleofsimpleoperationsonpoly-nomialsthatranbecarriedoutexacrlyifthecoefficientsarerational,andthedeterminationoftherealrootsofseveralunivariatepolynomials.

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简介：Apiecewisecubiccurvefittingalgorithmpreservingmonotonicityofthedatawithoutmodificationoftheassignedslopesigproposed.ThealgorithmhasthesameorderofconvergenceasYan’salgorithm[8]andGasparo-Morandi’salgorithm[5]foraccurateorO(hq)accurategivendata,butithasamorevisuallypleasingcurvethanthosetwoalgorithms.WealsodiscusstheconvergenceorderofcubicrationalinterpolationforO(hq)accuratedata.

简介：ＣＵＲＶＥＡＮＤＳＵＲＦＡＣＥＩＮＴＥＲＰＯＬＡＴＩＯＮＢＹＳＵＢＤＩＶＩＳＩＯＮＡＬＧＯＲＩＴＨＭＳＲｕｉｂｉｎＱｕＣＵＲＶＥＡＮＤＳＵＲＦＡＣＥＩＮＴＥＲＰＯＬＡＴＩＯＮＢＹＳＵＢＤＩＶＩＳＩＯＮＡＬＧＯＲＩＴＨＭＳ￥ＲｕｉｂｉｎＱｕＡｂｓｔｒａ...

简介：相配的曲线和表面是在CAD系统，不一致的合理B花键(NURBS)在被用作事实上的标准的重要操作。在本地角落相配，在那个角落交叉首先被做的二条曲线拆散，然后第三条相配的曲线是增加在里面的顺利与G1-orG2-continuity加入二条曲线。在这篇论文我们在场基于曲线扩展解决联合问题的研究。这个延期算法的下列好性质深入地被利用：(1)原来的形状的parameterization不变化；(2)没有另外的碎片被创造。各种各样的例子被举证明我们的答案简单、有效。

简介：Itisknownfromclassicaldifferentialgeometrythatonecanreconstructacurvewith(n-1)prescribedcurvaturefunctions,ifthesefunctionscanbedifferentiatedacertainnumberoftimesintheusualsenseandifthefirst(n-2)functionsarestrictlypositive.ItisestablishedherethatthisresultstillholdsundertheassumptionthatthecurvaturefunctionsbelongtosomeSobolevspaces,byusingthenotionofderivativeinthedistributionalsense.ItisalsoshownthatthemappingwhichassociateswithsuchprescribedcurvaturefunctionsthereconstructedcurveisofclassC∞.

简介：Theappriximationpropertiesofgeneralizedconiccurvesarestudiedinthispaper.Ageneralizedconiccurveisdefinedasoneofthefollowingcurvesortheiraffineandtranslatione-quivalentcurves:(i)coniccurvesiincludingparabolas,hyperbolasandellipses;(ii)generalizedmonomialcurves,includingcurvesoftheformx=yr,.rR.r=0,1,inthex-yCartesiancoordinatesystem;(iii)exponentialspiralcurvesoftheformp=Apolarcoordinatesystem.Thistypeofcurveshasmanyimportantpropertiessuchasconvexity,approximationproperty,effectivenumericalcomputationpropertyandthesubdivisionpropertyetc.Applicationsofthesecurvesinbothinterpolationandapproximationsusingpiecewisegeneralizedconicsegmentarealsodeveloped.Itisshownthatthesegeneralizedconicsplinesareverysimilartothecubicpolynomialsplinesandthebesterrorofapproximationisoratleastingeneralprovidedappropriateproceduresareused.Finallysomenumericalexamplesofinterpolationandappro

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简介：Objective:Toinvestigatethefeasibilityoftranscanalendoscopicmyringoplastyinthehandofyoungbeginnersurgeonswhohadjustcompletedtheresidencyprogramme.Methods:Inathreeyearperiod(August2012toAugust2015),44earsin42patientswereoperateduponbyabeginnersurgeonthroughthetranscanalendoscopicapproachinasubdistrictlevelhospitallocatedinthenorthwesternrangesoftheHimalayanregion.Results:Ofthe42patient,19weremaleand23female.Themeanagewas26.23years(range:15e47years).In40ears,completeperforationclosurewasachievedatsixmonths(successrate:90.9%).ThemeanairconductionPTApreoperativelywas40.84dBHLandimprovedto28.06dBHLpostoperatively(p<.001).ThemeanABgappreoperativelywas22.40dB,whichimprovedto9.1dBpostoperatively(p<.001).Conclusion:Endoscopictranscanalmyringoplastyissafeandreliableeveninyoungbeginners'hands.Surgeonscanconsiderendoscopicapproachearlyintheircareerswithoutthefearoflearningcurve.Thecostofendoscopicequipmentisaboutonetenthascomparedtoopenapproachunderaoperatingmicroscope,andanaddedadvantage.

简介：Receiveroperatingcharacteristic(ROC)curvesareoftenusedtostudythetwosampleprobleminmedicalstudies.However,mostdatainmedicalstudiesarecensored.UsuallyanaturalestimatorisbasedontheKaplan-Meierestimator.InthispaperweproposeasmoothedestimatorbasedonkerneltechniquesfortheROCcurvewithcensoreddata.Thelargesamplepropertiesofthesmoothedestimatorareestablished.Moreover,deficiencyisconsideredinordertocomparetheproposedsmoothedestimatoroftheROCcurvewiththeempiricalonebasedonKaplan-Meierestimator.ItisshownthatthesmoothedestimatoroutperformsthedirectempiricalestimatorbasedontheKaplan-Meierestimatorunderthecriterionofdeficiency.Asimulationstudyisalsoconductedandarealdataisanalyzed.

简介：Geometricparametersoftheturbinebladeareclassifiedaccordingtotheirdestinedfunctions,andthemathematicaldefinitionofthoseparametersinthesectioncurveisintroducedindetail.Somepartsofthesectioncurveshapecanbeadjustedfreely,offeringmoreflexibilitytodesigners.

简介：ThepurposeofthispaperistoinvestigateanewtypeofevolutionproblemforclosedconvexplanecurveswhichwillpreservestheperimeterofthecurvebutexpandstheenclosedareaandthefinallimitingcurveisacircleintheHausdorffmetricintheplane.

简介：AbstractBackground:Scoliosis secondary to neurofibromatosis type 1 (NF1) in children aged <10 years is an important etiology of early-onset scoliosis (EOS). This study was performed to investigate the curve evolution of patients with EOS secondary to NF1 undergoing bracing treatment and to analyze high-risk indicators of rapid curve progression.Methods:Children with EOS due to NF1 who underwent bracing treatment from 2010 to 2017 were retrospectively reviewed. The angle velocity (AV) at each visit was calculated, and patients with rapid curve progression (AV of >10°/year) were identified. The age at modulation and the AV before and after modulation were obtained. Patients with (n = 18) and without rapid curve progression (n = 10) were statistically compared.Results:Twenty-eight patients with a mean age of 6.5 ± 1.9 years at the initial visit were reviewed. The mean Cobb angle of the main curve was 41.7° ± 2.4° at the initial visit and increased to 67.1° ± 8.6° during a mean follow-up of 44.1 ± 8.5 months. The overall AV was 6.6° ± 2.4°/year for all patients. At the last follow-up, all patients presented curve progression of >5°, and 20 (71%) patients had progressed by >20°. Rapid curve progression was observed in 18 (64%) patients and was associated with younger age at the initial visit and a higher incidence of modulation change during follow-up (t = 2.868, P = 0.008 and <0.001, respectively). The mean AV was 4.4° ± 1.2°/year before modulation and 11.8° ± 2.7°/year after modulation (t = 11.477, P < 0.010).Conclusions:Curve progression of >10°/year is associated with younger age at the initial visit, and modulation change indicated the occurrence of the rapid curve progression phase.

简介：InCAGDandCG,energymodelisoftenusedtocontrolthecurvesandsurfacesshape.Incurve/surfacemodeling,wecangetfaircurve/surfacebyminimizingtheenergyofcurve/surface.However,ourresearchindicatesthatinsomecaseswecan'tgetfaircurves/surfaceusingthecurrentenergymodel.Soanimprovedenergymodelispresentedinthispaper.Examplesarealsoincludedtoshowthatfaircurvescanbeobtainedusingtheimprovedenergymodel.

简介：全部的变化(电视)最小化问题广泛地在图象恢复被学习。尽管许多其他的方法为它的答案被建议了，牛顿方法由于没有集中为最初的明确的表达仍然保持不可用。由禅宗，周和禅宗的以前的研究[15]认为一个规则化参数继续想法与一些成功而是没有柔韧的参数选择增加牛顿方法的集中的领域计划。在这份报纸，我们为一样的最初的电视明确的表达考虑一个homotopy方法并且建议使用曲线追踪适应地选择规则化参数。结果，这个想法帮助实质地在高效地解决TVEuler-Lagrange方程改进以前的工作。一样的想法也象deblurring问题一样为二个另外的方法被考虑，再与获得的改进。数字实验证明我们的新方法为图象恢复柔韧、快，甚至为有大noisy-to-signal比率的图象。

简介：NewalgorithmsbasedonartificialneuralnetworkmodelsarepresentedforcubicNURBScurveandsurfaceinterpolation.Whenallthknotspansareidentical,theNURBScurveinterpolationproceduredegeneratesintothatofuniformrationalB-splinecurves.Ifalltheweightsofdatapointsareidentical,thentheNURBScurveinterpolationproceduredegeneratesintotheintegralB-splinecurveinterpolation.

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简介：Montgomerymodularmultiplicationintheresiduenumbersystem(RNS)canbeappliedforellipticcurvecryptography.Inthiswork,unifiedmodularmultipliersovergeneralizedMersennenumbersareproposedforRNSMontgomerymodularmultiplication,whichenablesefficientellipticcurvepointmultiplication(ECPM).Meanwhile,theellipticcurvearithmeticwithECPMisperformedbymixedcoordinatesandadjustedforhardwareimplementation.Inaddition,theconversionbetweenRNSandthebinarynumbersystemisalsodiscussed.Comparedwiththeresultsintheliterature,ourhardwarearchitectureforECPMdemonstrateshighperformance.A256-bitECPMinXilinxXC2VP100fieldprogrammablegatearraydevice(FPGA)canbeperformedin1.44ms,costing22147slices,45dedicatedmultipliers,and8.25Kbitsofrandomaccessmemories(RAMs).

简介：精力最小化广泛地被使用了在象电脑辅助的几何设计那样的地里构造曲线和表面，计算机图形。然而，我们的严峻的例子证明精力最小化不有时优化曲线的形状。这份报纸学习在最小化紧张精力和曲线形状之间的关系，学习被与令人满意的形状构造一条立方的Hermite曲线执行。立方的Hermite曲线插入内推二个给定的端点的位置和正切向量。计算机模拟技术成为了科学发现的方法之一，学习进程被数字计算和计算机模拟技术执行。我们的结果显示出那：(1)立方的Hermite曲线不能被完全最小化紧张精力构造；(2)紧张精力由本地最小的采纳珍视，立方的Hermite曲线的形状能为大约60%所有情况被决定，其中一些然而有不能令人满意的形状。基于种类精力模型和分析，一个新模型为与令人满意的形状构造立方的Hermite曲线被介绍，它是种类精力的修正模型。新模型使用一个明确的公式计算二正切向量的大小，并且有性质：(1)计算是容易的；(2)它让立方的Hermite曲线当保持在曲线建设为一些盒子最小化种类精力的好性质时，有令人满意的形状。与最小的种类精力模型一起的新模型的比较被包括。