简介:Anewfastalgorithmtocomputemodularexponentiationforverylargeintegersisproposedinthispaper,whichisanimprovementofthefastRSAalgorithmbasedonSymmetryofModularMultiplication(SMM).TheSMMalgorithmobtainsthespeedimprovementbyconditionalsubstitutiononeverybasicoperationtodecreasetheabsolutevalueofproductandtheoperationnumbersofmodularreductions.Theproposedalgorithmcangetfasteroperationspeedbydecreasingthenumbersofbasicoperations.Comparedtoconventionalbinaryrepresentation,aspeedimprovementofapproximately47.5%wouldbeexpectedusingtheproposedalgorithm.
简介:Asaspecialshift-invariantspaces,splinesubspacesyieldmanyadvantagessothattherearemanypracticalapplicationsforsignalorimageprocessing.Inthispaper,wepayattentiontothesamplingandreconstructionprobleminsplinesubspaces.Weimprovelowerboundofsamplingsetconditionsinsplinesubspaces.Basedontheimprovedexplicitlowerbound,aimprovedexplicitconvergenceratioofreconstructionalgorithmisobtained.Theimprovedconvergenceratiooccupiesfasterconvergenceratethanoldone.Attheend,somenumericalexamplesareshowntovalidateourresults.
简介:速度体积处理(VVP)单个Doppler雷达的检索是能被用来获得许多风参数的一个有效方法。由于从方程的系数产生容易没被解决的一个性恶的矩阵的问题,然而,VVP方法没在操作足够地并且有效地被使用。在这篇论文,一个改进计划,基于原来的方法,SVVP(处理的步速度体积)被建议。改进算法通过一个逐步的过程检索风地的每组部件,它克服一个性恶的矩阵的问题,它当前限制VVP方法的申请。就算分析卷是很小的,在一个六参数的模型的变量能被检索。另外,在传统的方法存在的错误的来源和顺序被分析。改进方法被用于真实盒子,它证明它是柔韧的并且有能力获得本地对流系统的风地结构。它对学习暴风很有用。
简介:ThispaperexaminesthetertiaryteachingEnglishasaforeignlanguage(TTEFL)inChina.TheauthorfirstreviewscurrentliteratureonhowtoimproveChina’sTIEFLandthenpresentshisownperspectiveandsuggestionsforTTEFL’simprovementfocusingonadjustmentofteachinggoals,teacherimprovementandteacherqualitycontrol,learners’initiatives,languagelearningenvironment,assessmentpractice,andclassroomteachingpractice.
简介:Thispaperre-examinesBagnold’stheoremofsedimenttransport.DifferentfromthestreampowerdefinedbyBagnold,i.e.,τoV,thisstudyshowsthatthetotalloadofsediment-ladenflow,gt,isrelatedtonearbedenergydissipationrate,i.e.,τou*’.Anattemptismadetoexplaintheempiricalrelation.Theratio(=k)ofmeasuredtotalload,gt,totheproductofnearbedvelocity,u*’,andenergydissipationrate,τou*’,isanalyzed.ItisfoundthatkisindependentoftheRousenumber,Z,ifZisgreaterthan2.6,butthecoefficientkdecreaseswiththeincreaseofZwhenZ<2.6.AnempiricalrelationbetweenkandZisdeveloped.Asystematicandthoroughanalysisof1,458setsofdatacollectedfrom16riversandcanalsconfirmsthattheproposedformulacanbeusedtocomputethetotalloadwithaccuracy.
简介:Formanyclusteringalgorithms,itisveryimportanttodetermineanappropriatenumberofclusters,whichiscalledclustervalidityproblem.Inthispaper,anewclusteringvalidityassessmentindexisproposedbasedonanovelmethodtoselectthemarginpointbetweentwoclustersforin-ter-clustersimilaritymoreaccurately,andprovidesanimprovedscatterfunctionforintra-clustersimilarity.Simulationresultsshowtheeffectivenessoftheproposedindexonthedatasetsunderconsiderationregardlessofthechoiceofaclusteringalgorithm.
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简介:Usinglinearinterpolationmethod,VIREalgorithmsimplytreatsthesignalstrengthvalueanddistanceofthereferencetagasalinearrelationship,leadingtotheinaccuracyofsignalstrengthvalueforvirtualreferencetags.ThethresholdinVIREalgorithmisafixedvaluethatneedsrepeatedlyadjustmentthroughexperiments,whichresultsinthecomplicatedalgorithm.Tosolvetheseproblems,animprovedalgorithmisproposedinthispaper,includingnonlinearinterpolationalgorithm,dynamicthresholdsettingandtagself-correctionoffuzzymap,whichbuildsanindoorpositioningsystembasedonreferencetags.Theexperimentalresultsshowthattheimprovedalgorithmcanimprovethepositioningaccuracyandimprovethestabilityofpositioningresultsunderbadenvironmentalconditionswithoutincreasingthenumberofreferencetags.
简介:Animprovedconstrained(IC)steeringlawforsinglegimbalcontrolmomentgyros(SGCMGs)withdeformedpyramidconfiguration(DPC)isproposed.Firstofall,theoriginalsystemwithfivepyramidconfiguration(FPC)whosetwoadjacentgyrosareinfailurestateisreconfiguredasadegradedsystemwithDPC.Then,thesingularangularmomentumhypersurfacesoftheoriginalandthedegradedsystemsareplottedviathesingularangularmomentumequationofSGCMGs.Basedonsingularsurfaces,thedifferencesbetweenFPCandDPCinsingularityandmomentumenvelopeareobtaineddirectly,whichprovideanimportantreferenceforsteeringlawdesignofDPC.Finally,anICsteeringlawisdesignedandappliedtoDPC.ThesimulationresultsdemonstratethattheICsteeringlawhasadvantagesinsimplicityofcalculation,avoidanceofsingularityandexactnessofoutputtorque,whichendowthedegradedsystemwithfinecontrollabilityinarestrictedworkspace.
简介:象在1975一样早,Shamos和Hoey首先给了O(nlgn)-timedivide-and-conquer算法(嘘算法在短)为发现点的最靠近的对的问题。在联合的一个过程,在一些点需要被计算的3n之间的欧几里得距离,计算距离的全面复杂性当时因此是3nlgn。因为距离的计算与另外的基本操作相比是更昂贵的,怎么嘘改善从计算距离的复杂性的方面的算法被考虑。在1998,周,熊和朱由把这复杂性归结为2nlgn改进了SHalgorithm。在这篇论文,我们做进一步的改进。计算距离的Theoverall复杂性被归结为(3nlgn)/2,它仅仅是一半SHalgorithm的。
简介:多代理签名是一位原来的签名人托付签署能力到一个代理组的一个计划。在计划,仅仅在代理组的所有代理签名人的合作能代表原来的签名人创造签名。Jin和皮脂腺囊瘤第一定义无证书的多代理签名(CLMPS)的正式安全模型并且建议了一个具体CLMPS计划。然而,他们的构造有三个问题:加强的安全模型的定义是不精密的,具体签名计划有一个安全缺陷,并且安全的证明是有瑕疵的。与进一步的考虑,一个补救加强的安全模型被重新定义,并且一个改进计划是也存在地求婚了,它是unforgeable对适应地,选择保证,选择消息和选择身份在随机的神谕攻击。处于这个条件,计算Diffie-Hellman(CDH)假设被用来为我们的CLMPS计划证明安全完整。