简介：TheConwaypotentialfunction(CPF)forcoloredlinksisaconvenientversionofthemultivariableAlexander–Conwaypolynomial.WegiveaskeincharacterizationofCPF,muchsimplerthantheonebyMurakami.Inparticular,Conway’s"smoothingofcrossings"isnotintheaxioms.Theproofusesareductionschemeinatwistedgroup-algebraP_nB_n,whereB_nisabraidgroupandP_nisadomainofmulti-variablerationalfractions.Theproofdoesnotusecomputeralgebratools.Aninterestingby-productisacharacterizationoftheAlexander–Conwaypolynomialofknots.

简介：Toestablishanefficientinter-satellitelink(ISL)inanLEOnetwork,theeffectofgeometriccharacteristicsofISLontheISLsandthedevicesontheLEOsatelliteshouldbeexamined.BecauseofthecontinuousmovementoftheLEOsatellite,thetime-varyingbehavioursoftheISL'sgeometriccharactersisticscontinuouslychangewiththechangesofthesatellite'spositionontheorbit.ThesedynamicgeometriccharacteristicsoftheISLsareimportantforISL'sperformanceanalyzingandthedesignofthedevicesontheLEOsatellite.ThispaperdescribesdynamicgeometriccharacteristicsofISL,analyzestheimpactoftheseregulationsonthetrackingsystemofthesatellite'santennaandthepoweradjustingsystemofthesatellite'stransmitter,withtheIridiumsystemasanexample.

简介：Fromthecomparisonofcorrelationtensorinthetheoryofquantumnetwork,theAlexanderrelationmatrixinthetheoryofknotcrystalsandtheidenticalinversionrelationsundertheactionofPaulimatrices,weshowthatthereisaonetoonecorrespondencebetweenfourBellbasesandfourorientedlinksofthelinkage41inknottheory.

简介：有由于季风系统的复杂性在中国预言植被回答到东方亚洲季风(电动会计记帐机)可变性的简单方法的缺乏。在这研究，我们发现了变化西方的和平的副热带的高度(WPSH)是EAM的主要部件之一，在中国在植被生长上有深刻影响。当WPSH更被定位到它的气候一般水准的西方时，东方、西北的部分分别地由0.3%-2.2%，和0.2%-2.2%经历增加的每年一般水准的规范的差别植被索引(NDVI)和粗野主要生产率(GPP)。相反，当WPSH更被定位到它的气候的东方时，平均，上述区域分别地在0.4%～1.6%，和1.3%～4.5%经历减少的每年一般水准的NDVI和GPP。WPSH用作一个主要发行量索引预言植被的反应到季风。

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简介：Manypeoplehavebeguntoconcernaboutthepotentialresourcesshortagesagainstthebackdropofrapideconomicgrowth.PaulKrugmanwroteanarticletitled‘RunningoutofPlanettoexploit’,andinthisarticle,theauthorwilladdresstheKrugmanquestion,andtoconsiderwhetherthekeyfactoristhedecision-makingcapacityoftheinternationalcommunityindealingwithandadaptingtothesubstantialinteractionsbetweenenergy,land,water,andfoodsupply,andthepotentialglobalresourcescarcitiesinthesefourareas—thelinksandlimitsinthepaper’stitle.

简介：<正>MostofU-depositsofChina,speciallythelargeU-deposits,aresimilartotheU-depositsofmanycountries.Therearecloserelationsbetweentheirformation,distributionsoftimeandspaceandthetectono-magmaticactivationofcrust.Thetectono-magmaticactivationdiscussinginthispaper(thefollowingcalledactivationforshort)isonlyconfinedtotheactivationaftergeosynclinestageortheconsolida-tionofplatform.Asaresult,thepalingeneticgeosynclineandmedianmassifalsobelongtothediscussingscope.Thetectono-magmatismofgeosynclinestageitselfanditsrelevantU-depositsdonotbelongtothe

简介：Weproposetheuseofapowerpulseshapeofthewidelyknownopticalsoliton,correspondingtothehyperbolicsecantsquarefunction,forbothconventionalatmosphericopticalcommunicationsystemsand,especially,fornewfull-opticalwirelesscommunications.Weanalyzetheperformanceoftheproposedpulseintermsofpeak-to-averageopticalpowerratio(PAOPR)andbiterrorrate(BER).Duringtheanalysis,wecomparetheproposedpulseshapeagainstconventionalrectangularandGaussianpulseshapeswithreduceddutycycle.Resultsshowthenoticeablesuperiorityoftheproposedpulseforatmosphericopticallinks.

简介：Thethermaldistortionofanopticalreflectorsurfaceduetothechangingsunlightinaspaceenvironmentwillcauseshiftandspreadingofitsreflectedfocusandtherebyinfluencetheperformanceofspace-to-groundlasercommunicationlinks.Basedonthecharacteristicsofaloworbitsatellite,thenormalshiftofaplanmirrorcausedbythermaldistortionisanalyzedwiththesoftwareoftheANSYSoffiniteelementanalysis.Ageneralexpressionofthetransmittedbeamfromadistortedreflectorsurfaceandacountingformulafortheshiftsofthefocuscenterbeforeandafterthermaldistortionarededuced.Theresultofsimulationshowsthatthemagnitudeorderofthenormalshiftoftheantennamirrorsurfacecanbeashighastensofμrad.Theworsethemirrorthermaldistortionis,thelargertheshiftofthereceivedfocuscenteris.Andthechangeoftheshiftsdoesnotobeyalinearrule.

简介：Thechain/wirerope/chaincombinationisacommonchoiceformooringoffshorefloatingplatforms.However,dataofthedragcoefficientsofchainlinksareratherlimited,resultinginuncertaintieswiththecalculationsofthedragforce,andhencethedampingofthemooringsystem.Inthispaper,theimportanceoftheselectionofthedragcoefficientisfirstinvestigated.Thecomputationalfluiddynamics（CFD）methodisthenusedtodeterminethedragcoefficientsofastudlesschainundersteadyflows.Numericalmodelvalidationisfirstcompletedbysimulatingasmoothcircularcylinderundersteadyflows.Inparticular,theperformanceofdifferentturbulencemodelsisassessedthroughthecomparisonsbetweenthecalculationsandtheexperimentalresults.Thelargeeddysimulation（LES）modelisfinallyselectedforthesimulationofsteadyflowspastachain.TheeffectsoftheReynoldsnumberonthedragcoefficientofastud-lesschainisalsostudied.Theresultsshowthatthecalculateddragcoefficientsofastud-lesschainarefairlyconsistentwiththeavailableexperimentaldata.

简介：Non-linearfiniteelementmodelsaccountingforlargedisplacementshavebeenusedtoinvestigatethebehaviorofsteelbuilt-upshearlinksthathadpreviouslybeentestedusinglarge-scaleexperiments.Thelinksweredesignedusingstcclgradeswithyieldpointsrangingfromhightolowstrengths.Theobjectivesofthcnumericalanalysesweretofurtherinvestigatethenon-linearbehaviorandtocorrelatethenumericalresultswithexperimentalobservations.Elasto-plasticaswellascyclicstress-strainmaterialpropertieswereincorporatedtostudytheinfluenceofmaterialbehaviorontheoverallshearlinkresponse.Non-linearmonotonicanalysesoftheshearlinksincorporatingthecyclicstress-strainsteelpropertiesresultedinsimilartrendsintheresponseasthebackbonecurvesrecordedfromthephysicalexperiments.Thenumericalmodelsofbuilt-upshearlinksutilizingstructuralgradesteelscloselycorrelatedtotheexperimentallyrecordedshearstrength.Modelsutilizinglowyieldpointsteelsoverestimatedtheshearstrength,whichwascausedbythecharacteristicsofcyclicbehaviorofthosesteels.Thedetailednumericalmodelsalsoallowedforinvestigationoftheplasticstraindemandsonthedifferentcomponentsofthelink.Itwasshownthatfiniteelementmodelscombinedwithappropriatestress-strainrelationshipmaybeusedwithconfidencetocheckthedesignofshearlinksofdifferentsteelgradesandsectionalgeometries.

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简介：Thcrearecloseinnerlinksbetweenthetimeandspatialdistributionsofpolygeneticcompoundlarge/superlargeU-depositsanddiwatectonicinterfaces.ixwatectonicinterfacesaredividedintotwotypes,namely,oneinspaceandtheotherintimc.Thcfollowin8tcctonicintcrfacesallbclongtodiwaspatialtyPc:l)Gcotcctonicunconformityintcr

简介：一个改进方法被建议模仿骚乱介绍的焕发，基于有限Markov州的模型。作为到文学的一个对比，一致地分布式的变量发生在某个状态期间，它比传统的Markov模型与更少状态贡献紧张变化的相等的模拟。它的也发现有20个状态的建议Markov模型在汽车协变性分析提供令人满意的近似给试验性的结果。而且，停止概率和吝啬的褪色时间是比有相等的状态的传统的Markov模型的那些更精确的。

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