简介:各种各样的途径为解决许多连续全球优化问题被开发了。但是直到现在,更少的工作被奉献给由于固有的困难解决非线性的整数编程问题。这篇论文设法把一般非线性的整数编程问题转变成一个equivalent'专辑连续全球最小化问题。因此,任何有效全球优化算法能被用来解决非线性的整数编程问题。这结果将也在全球优化上支持研究。我们在场一个间隔Branch-and-Bound算法。数字实验证明这条途径是有效的。(作者摘要)11个裁判员。
简介:OneoftheprincipaldisadvantagesofOrthogonalFrequencyDivisionMultiplexing(OFDM)isverysensitivetocarrierfrequencyoffset.Theintegerfrequencyoffsethasnoeffectontheorthogonalityamongthesubcarriers,butitcausesacircularshiftandphaserotationofthereceiveddatasymbolssequence,resultinginaBitErrorRate(BER)of0.5.Inthispaper,anovelintegerfrequencyoffsetestimatorforOFDMisderivedbasedonmaximumlikelihoodestimationtechniqueandexplorationofthedifferentialrelationbetweentwoconsecutiveOFDMdatasymbolsequencesinfrequencydomain.ItsperformanceiscomparedwiththeconventionalmethodbycomputersimulationsfortheadditivewhiteGaussiannoisechannelandamultipathfadingchannel.Simulationresultsshowthattheperformanceoftheproposedestimatorisbetterthantheconventionalestimator.
简介:Adiscretedifferentialevolutionalgorithmcombinedwiththebranchandboundmethodisdevelopedtosolvetheintegerlinearbilevelprogrammingproblems,inwhichbothupperlevelandlowerlevelvariablesareforcedtobeinteger.Anintegercodingforupperlevelvariablesisadopted,andthenadiscretedifferentialevolutionalgorithmwithanimprovedfeasibility-basedcomparisonisdevelopedtodirectlyexploretheintegersolutionattheupperlevel.Foragivenupperlevelintegervariable,thelowerlevelintegerprogrammingproblemissolvedbytheexistingbranchandboundalgorithmtoobtaintheoptimalintegersolutionatthelowerlevel.Inthesameframeworkofthealgorithm,twootherconstrainthandlingmethods,i.e.thepenaltyfunctionmethodandthefeasibility-basedcomparisonmethodarealsotested.Theexperimentalresultsdemonstratethatthediscretedifferentialevolutionalgorithmwithdifferentconstrainthandlingmethodsiseffectiveinfindingtheglobaloptimalintegersolutions,buttheimprovedconstrainthandlingmethodperformsbetterthantwocomparedconstrainthandlingmethods.
简介:InviewoftheshortcomesofconventionalElectroCardioGram(ECG)compressionalgo-rithms,suchashighcomplexityofoperationanddistortionofreconstructedsignal,anewECGcompressionencodingalgorithmbasedonSetPartitioningInHierarchicalTrees(SPIHT)isbroughtoutafterstudyingtheintegerliftingschemewavelettransformindetail.Theproposedalgorithmmodifieszero-treestructureofSPIHT,establishessingledimensionalwaveletcoefficienttreeofECGsignalsandenhancestheefficiencyofSPIHT-encodingbydistributingbitsrationally,improvingzero-treesetandamelioratingclassifyingmethod.Forthisimprovedalgorithm,floating-pointcom-putationandstorageareleftoutofconsiderationanditiseasytobeimplementedbyhardwareandsoftware.Experimentalresultsprovethatthenewalgorithmhasadmirablefeaturesoflowcomplexity,highspeedandgoodperformanceinsignalreconstruction.Highcompressionratioisobtainedwithhighsignalfidelityaswell.
简介:Inthispaper,wenotonlyconstructtheconfidenceregionforparametersinamixedinteger-valuedautoregressiveprocessusingtheempiricallikelihoodmethod,butalsoestablishtheempiricallog-likelihoodratiostatisticandobtainitslimitingdistribution.Andthen,viasimulationstudieswegivecoverageprobabilitiesfortheparametersofinterest.Theresultsshowthattheempiricallikelihoodmethodperformsverywell.
简介:Reliabilityallocationproblemiscommonlytreatedusingaclosed-formexpressionrelatingthecosttoreliability.Arecentapproachhasintroducedtheuseofdiscreteintegertechniqueforun-repairablesystems.Thisresearchaddressestheallocationproblemforrepairablesystems.ItpresentsanintegerformulationforfindingtheoptimumselectionofcomponentsbasedontheintegervaluesoftheirMeanTimetoFailure(MTTF)andMeanTimetoRepair(MTTR).Theobjectiveistominimizethetotalcostunderasystemreliabilityconstraint,inadditiontootherphysicalconstraints.Although,aclosed-formexpressionrelatingthecosttoreliabilitymaynotbealinear;however,inthisresearch,theobjectivefunctionwillalwaysbelinearregardlessoftheshapeoftheequivalentcontinuousclosed-formfunction.Anexampleissolvedusingtheproposedmethodandcomparedwiththesolutionofthecontinuousclosed-formversion.Theformulationforallpossiblesystemconfigurations,componentsandsubsystemsarealsoconsidered.
简介:Anewhyperspectralimagecompressionmethodofspectralfeatureclassificationvectorquantization(SFCVQ)andembeddedzero-treeofwavelet(EZW)basedonKarhunen-Loevetransformation(KLT)andintegerwavelettransformationisrepresented.Incomparisonwiththeothermethods,thismethodnotonlykeepsthecharacteristicsofhighcompressionratioandeasyreal-timetransmission,butalsohastheadvantageofhighcomputationspeed.AfterliftingbasedintegerwaveletandSFCVQcodingareintroduced,asystemofnearlylosslesscompressionofhyperspectralimagesisdesigned.KLTisusedtoremovethecorrelationofspectralredundancyasone-dimensional(1D)lineartransform,andSFCVQcodingisappliedtoenhancecompressionratio.Thetwo-dimensional(2D)integerwavelettransformationisadoptedforthedecorrelationof2Dspatialredundancy.EZWcodingmethodisappliedtocompressdatainwaveletdomain.ExperimentalresultsshowthatincomparisonwiththemethodofwaveletSFCVQ(WSFCVQ),themethodofimprovedBiBlockzerotreecoding(IBBZTC)andthemethodoffeaturespectralvectorquantization(FSVQ),thepeaksignal-to-noiseratio(PSNR)ofthismethodcanenhanceover9dB,andthetotalcompressionperformanceisimprovedgreatly.
简介:Hartree-Fock-Roothaan(HFR)calculationsforgroundstatesofsomeatoms,i.e.He,Be,Ne,Ar,andKrhavebeenperformedusingminimalbasissetsofSlatertypeorbitals(STOs)withintegerandnonintegerprincipalquantumnumbers(integern-STOsandnonintegern-STOs).Theobtainedtotalenergiesfortheseatomsusingminimalbasissetsofintegern-STOsareingoodagreementwiththoseinthepreviousliterature.Ontheotherhand,forthecaseofminimalbasissetsofnonintegern-STOs,althoughthecalculatedtotalenergiesoftheseatomsagreewellwiththeresultsinliterature,somestrikingresultshavebeenobtainedforatomsArandKr.OurcomputationalresuitsfortheenergiesofatomsArandKrareslightlybetterthanthoseinliterature,byamountof0.00222and0.000054a.u.,respectively.TheimprovementintheenergiesofatomsArandKrmayresultfromtheefficientcalculationsofone-centertwo-electronintegralsovernonintegern-STOs.Forsomeatomicionsintheirgroundstate,HFRcalculationshavebeencarriedoutusingminimalbasissetsofnonintegern-STOs.Theobtainedtotalenergiesfortheseatomicionsaresubstantiallylowerthanthoseavailableinliterature.