简介：Inthispaper,theSpaceWeatherModelingFramework(SWMF)isusedtosimulatethereal-timeresponseofthemagnetospheretoasolarwindeventonJune5,1998,inwhichtheinterplanetarymagneticfieldshifteditsdirectionfromnorthtosouth.Sincemostcurrentmodelsdonottakeintoaccountconvectiveeffectsoftheinnermagnetosphere,wefirststudytheimportanceofRiceConvectionModel(RCM)intheglobalmodel.Wethenfocusonthefollowingfouraspectsofthemagnetosphere’sresponse:themagnetosphere’sdensitydistribution,thestructureofitsmagneticfieldlines,theareaofthepolarcapboundary,andthecorrespondingionosphericcurrentchange.Wefindthat(1)whentheIMFchangesfromnorthtosouthinthisevent,highmagnetosheathdensityisobservedtoflowdownstreamalongthemagnetopausewiththesolarwind;low-latitudereconnectionatdaysideoccursunderthesouthwardIMF,whilethemagneticfieldlinesinthetaillobecaudal,causedbythenightsidehighlatitudereconnection,extendintotheinterplanetaryspace.Openmagneticfieldlinesexistsimultaneouslyatbothhighandlowlatitudesatthemagnetopause;(2)theareaofthepolarcapisobviouslyincreasediftheIMFturnsfromthenorthtothesouth;thisobservationishighlyconsistentwithempiricalobservations;(3)theionosphericfieldaligncurrentinthenorthernhemisphereisstrongerthaninthesouthernhemisphereandalsoincreasesastheIMFchangesfromnorthtosouth.SWMFwiththeRiceConvectioneffectprovidesreliablemodelingofthemagnetosphericandionosphericresponsetothissolarwindvariation.

简介：Datingbackto1933,SCNU'sPhysicsdisciplinewasselectedforthenationalproject"World-ClassDisciplineDevelopment"bytheMinistryofEducationin2017.CurrentlytheSchoolacceptsanaverageof1800full-timeundergraduatesand500postgraduateresearchstudents,producingapproximately20000graduatessinceitsfoundation.

简介：TostudythespatialdifferenceofoceanambientnoiseinoffshoreChinaandrevealitsgenerationmechanism,thedifferencebetweenthenoiselevel(NL)oftwostationsiscomparedbasedonlong-termobservationdatacollectedinthesameseason.Consideringtheinfluenceofunderwateracousticchannelsandthecharacteristicsofnoisesources,thetransmissionlosslevel(TL)fromtheportshipnoisesourcestothemeasuringstationisanalyzedanditshowsastrongcorrelationbetweenthetransmissionlossdifference(TLD)andnoiseleveldifference(NLD)atthebandof50-500Hz.Atthesametime,theanalysisofshipnoisesourcelevel(SL)presentsadifferenceabout20dBbetweenthetwoports,correspondingtothevariationoftheshipdensitybeforeandduringthefishingmoratorium.Theresultsprovethattheambientnoiseiscloselyrelatedtoshipnoisesourcesatthisfrequencyband,andthenoisedifferencebetweenthetwostationsresultsfromthetransmissionlossandtheshipnoisesources.

简介：Thequantitativeinterpretationofgravityanomaliesduetoshallowstructuresneedsseparationbetweenlongwavelengthanomalies(regionalanomalies)andshortwavelengthanomalies(residualanomalies).Theregional-residualfieldseparationcanbecarriedoutusingthepolynomialmethod.Inthiscase,theso-calledregionalfieldofordernistreatedasapolynomialofdegreen.Thepresentstudyshowsthatthedegreenmustvarybetweenasmallestvaluenminandamaximumvaluenmax.Thisarticlepresentsamethodtoprocessgravitydatathatallowsdeterminationofnminandnmaxforagivenstudyarea.WeapplythemethodtogravitydataoftheSouth-WestCameroonzone.Inthischosenstudyarea,wefindthatregionalanomalymapsofordersrangingfrom1to9andresidualanomalymapsofordersrangingfrom1to8canbeusedforsuitableinterpretation.Theanalysesshowthatonemayneedresidualanomalymapsofseveralorderstoperformsatisfactoryquantitativeinterpretationofthedifferentintrusivebodiesfoundinagivenarea.

简介：Environmentalloadistheprimaryfactorinthedesignofoffshoreengineeringstructuresandoceancurrentistheprincipalenvironmentalloadthatcausesunderwaterstructuralfailure.Incomputationalanalysis,thecalculationofcurrentloadismainlybasedonthecurrentprofile.Thecurrentprofilemodel,whichisbasedonastructuralfailurecriterion,isconducivetodecreasingtheuncertaintyofthecurrentload.Inthisstudy,weusedprototypemonitoringdataandtheempiricalorthogonalfunction(EOF)methodtoinvestigatethecurrentprofileintheSouthChinaSeaanditscorrelationwiththedesignofunderwaterstructuralstrengthandthedynamicdesignoffatigue.Theunderwaterstructuralstrengthdesigntakesintoaccountthesizeofthestructureandtheservicewaterdepth.Weproposeprofilesfortheoverallandlocaldesignsusingtheinversefirst-orderreliabilitymethod(IFORM).Weextractedthecharacteristicprofilecurrent(CPC)ofthemonitoredseaareatosolvedynamicdesignproblemssuchasvortex-inducedvibration(VIV).WeusedrandomsamplingtoverifythefeasibilityofusingtheEOFmethodtocalculatetheCPCfromthecurrentdataandidentifiedthemainproblemsassociatedwithusingtheCPC,whichdeservecloseattentioninVIVdesign.Ourresearchconclusionsprovidedirectreferencesfordeterminingcurrentloadinthisseaarea.Thisanalysismethodcanalsobeusedintheanalysisofotherseaareasorfieldvariables.

简介：Thevolcano-sedimentarysuccessionaroundWadiZaghrainSinai,atthenorthernmostsegmentoftheArabianNubianShield,comprisesvolcanicrocksinterbeddedwithratherimmaturesediments.Thesuccessionisdominatedbyintermediatetosilicicvolcanicsofmedium-tohigh-Kcalc-alkalineaffinity.Itisdividedintotwounits,thelowerunitincludesintermediaterocksanddacitesinterbeddedwithgraywackes,semi-pelitesandpelitesandtoppedbypolymictconglomerates.Thisunitissubjectedtofoldingandregionalmetamorphism(uptogarnetzone)andisintrudedbyquartzdiorite-granodioriteinducing,locally,low-pressurecontactthermalmetamorphism.Theunmetamorphosedupperunitencompassesacidvolcanicsintercalatedwithlitharenite,sublithareniteandminorarenite.Therhyolitesofthisunitpertaintothehighlyfractionatedgranitesandarecharacterizedbyanagpaiticindex(NK/A)rangingfrom0.87to0.96.Theymayreflecteitherextensiveinteractionofsubduction-relatedmagmaswiththecontinentalcrustorachangeinthetectonicregime.Thepresentlithologicalandgeochemicalcharacteristicsofthestudiedsedimentstogetherwithavailablezirconagesindicateratherdistalprovenanceoftheirdetritus.Thisdetrituscomprisesfluvial-alluvialsedimentsaccumulatedintheintermontanebasins,whicharehalf-grabensortiltedfaultblocks.Thetectonicsettingofthedepositionalbasinsisactivecontinentalmarginandcontinentalislandarcs.GeochemicalpatternsoftheZaghravolcano-sedimentarysuccessionindicatetheircorrelationwiththeDokhanVolcanics-HammamatClasticssequenceoftheEasternDesertofEgypt.Also,theZaghravolcanicsdisplaygeochemicalsimilaritieswiththoseexposedinSinai,attheRutig,FeraniandIqnaShar’aareas.TheZaghrasuccessionisdatedasEdiacaranbutisnotrelatedeithertotheensimaticislandarcassemblageortotherift-relatedassemblageformedduringtheearlystagesofthebreak-upofRodiniaaspreviouslythought.