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简介：INMay2013,YunnanChihongZincandGermaniumCo.,Ltd.（Chi-hongZn＆Ge）bought51percentofthesharesoftwoBolivianminingcompaniesandundertookamonth-longevaluationofthemines＇localenviron-ments.LaRazonnewspaper,whichhasthebiggestcirculationinBolivia,reportedChihong＇sacquisitionwiththeheadline＂Chinaassessestheenviron-mentalimpactoftheirinvestments,＂claimingthattheminingprojectswerethefirsttopassthetestinBolivia.

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简介：Thedualrandommodelsaboutthelifeinsuranceandsocialpensioninsurancehavereceivedconsiderableattentionintherecentarticlesonactuarialtheoryandapplications.Thispaperdiscussesageneralkindofincreasingannuitybasedonitsforceofinterestaccumulationfunctionasageneralrandomprocess.Thedualrandommodelofthepresentvalueofthebenefitsoftheincreasingannuityhasbeenset,andtheirmomentshavebeencalculatedundercertainconditions.

简介：Inthispaperthegeneraldynamicalequationsweregivenformultibodiesmanipulator.Thesystemisatopologictreestructureconsistingofarbitrarynumberofrigidbodies.Thehingesallowtherotationaland/ortranlationalmotion.InconsiderationofinfluenceoffrictionthedynamicequationsareestablishedbymeansofNewton-Euler’smethod.Further,theequationsareseparatedbywayofconstructingthedistributionmatricesandagroupofforceandmotionequationsareobtained.

简介：TheDiracsymbolisusedtorepresentthediscretecomplexHopfieldneuralnetworkmodel.Thesignal-to-noisetheoryandthecomputernumericalsolu-tionaremadetoanalysethestoragecapacityofthemodel.Thestoragecapacityra-tioofthemodelequalstothatoftheHopfieldmodel.Finally,usingthemodeltorecognizethe4-levelgreyorcolorpatternsisdiscussed.

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简介：InthispaperamathematicalmodelofAIDSisinvestigated.Theconditionsoftheexistenceofequilibriaandlocalstabilityofequilibriaaregiven.TheexistencesoftranscriticalbifurcationandHopfbifurcationarealsoconsidered.inparticular,theconditionsfortheexistenceofHopfbifurcationcanbegivenintermsofthecoefficientsofthecharacteristicequation.ThemethodextendstheapplicationoftheHopfbifurcationtheoremtohigherdifferentialequationswhichoccurinbiologicalmodels,chemicalmodels,andepidemiologicalmodelsetc.

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简介：我们与处理描述并且分析一个简单SIS模型。特别地，我们借助于asymptotically自治的系统的理论给完全质的分析。如果足够的接触率或能力是小的，向后的分叉发生，这被发现。在那里存在，也被发现双稳态地方性的equilibria。在导致疾病的死亡的情况中，向后的分叉也发生，这被显示出。而且，在一些条件，和潜水艇下面没有限制周期批评Hopf分叉发生在另外一个下面条件。

简介：AnellipticalwindfieldmodeloftyphoonsisputforwardbasedonthecharacteristicsofthetyphoonwindfieldsoccurringintheYellowSeaandBohaiSea.Bycontrastingitwiththecirculartyphoonwindfieldmodel,itisfoundthattheellipticalmodelcanadequatelyrepresenttherealwindfieldandtracetheprocessofatyphoonstormsurge.Thenumericallysimulatedresultsofstormsurgesbyusingtheellipticalmodelareingoodagreementwiththeobservationsandmarkedlybetterthanthosebyusingthecircularmodel.

简介：ThispaperisfocusedonthemodelidentificationofaMicroAirVehicle(MAV)instraightsteadyflightcondition.Theidentificationisbasedoninput-outputdatacollectedfromflighttestsusingbothfrequencyandtimedomaintechniques.Thevehicleisanin-house40cmwingspanairplane.Becauseofthecomplexcoupled,multivariableandnonlineardynamicsoftheaircraft,linearSISOstructuresforboththelateralandlongitudinalmodelsaroundareferencestatewerederived.TheaimoftheidentificationistoprovidemodelsthatcanbeusedinfuturedevelopmentofcontroltechniquesfortheMAV.

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简介：ThisworkhasoriginallybeendoneintheP.R.China(WuhanTechnicalUniversityofSurveyingandMapping)andinHongKong(ChineseUniversityofHongKong).Prof.LinHuigaveusefuladvice.Mr.HanHaiyang,andMs.ChenLilihelpedworkwiththeimplementationofprototypesystem.WealsothanktheSwissNationalScienceFoundationforitsfinancialsupportandacknowledgethecommentsofDr.AndreasGeppertandProf.KlausR.Dittrichonanearlierversionofthispaper.

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简介：Thepurposeofthisstudyistodevelopasimplifiedmathematicalmodeltosimulatesuspendedsolidsandtotalphosphorusconcentrationsinawetlandordetentionpond.Fielddatacollectedfromawetdetentionpondduringstormswereusedtodemonstratetheapplicationofthismodel.Favorableagreementsbetweenthemodelresultsanddatawereachieved.Theratioofaverageoutletmethodandsummaryofloadsmethodwereusedtoquantifytheremovalefficiencyofpollutants,reflectingtheefficienciesareveryclose.Theresultsofthisstudycanbeusedfornonpointsourcepollutioncontrol,wastewatertreatmentorbestmanagementpractices(BMPs)throughthewetland.

简介：Basedontheprincipleofsimilarity,waterwasusedtosimulatetheflowofmoltensteeltoanalyzetheflowfieldinatundish.Severalschemesofthetundish’stracershapeweredesignedandcorrespondingwatermodelexperimentswereconducted.Duringtheexperiments,acomputerautomaticallycollecteddata.Thecomparisonoftheresidencetimedistribution(RTD)curvesdrawnaccordingtothecomputer-collecteddataoptimizedtheschemeandphotographsoriginatedfromtheexperimentswithinkasitstracer.Itindicatesthatthewatermodelcanoptimizetheflowfieldofthetundish.