简介：

简介：

简介：ＯｂｓｔａｃｌｅｓｔｏｂｅＯｖｅｒｃｏｍｅｉｎＩｍｐｒｏｖｉｎｇｔｈｅＳｔａｔｕｓｏｆＣｈｉｎｅｓｅＷｏｍｅｎ￥／ＺｏｕＸｉａｏｑｉａｏ（ＴｈｅＡｌｌＣｈｉｎａＷｏｍｅｎ＇ｓＦｅｄｅｒａｔｉｏｎ）ＩｎＣｈｉｎａ，ｔｈｅｒｅａｒｅｐｒｅｓｅｎｔｌｙ７０...

简介：

简介：Withdrasticchangesinboththeinternationalanddomesticenvironmentforpopulationandfamilyplanningdevelopment,Chinafacesninemajorchallengesinitseffortstofurtheritspopulationandfamilyplanningprogram,saidZhangWeiqing,MinisteroftheNationalPopulationandFamily

简介：ThedevelopmentofplantationplaysaveryimportantroleinforestryindustrydevelopmentinChinabecauseofitsuniqueadvantages.However,theecologicalandenvironmentalissuesurgentlyrequiresustainableplantationdevelopment.FSCcertificationforsustainableforestmanagementbalancestheeconomic,environmentalandsocialbenefitsandcontributestosustainabledevelopmentofplantation.FSCcertificationforplantationissignificantlyimportanttoChinawiththemostplantationareainthewor...

简介：

简介：SpaceisanimportantpartoftheSino-USrelationship.Itreflectsthegeneraldirectionofbilateralrelations,yethasitsowndevelopmenttrajectory.AsSino-USrelationshadtheirupsanddownsinthe1990s,spacecooperationbetweenthetwocountrieswasrelativelyconsistentandstable.Butaseconomyandtradebecamemoreandmoredeeplyintertwinedinthe21stcentury,spacecooperationlostitsmomentum.Thispaperintendstoexplorethereasonsbehindthisstrangedevelopmenttrajectorybyanalyzingthesecurity,political,legislativeandeconomicfactorsaffectingbilateralspacecooperation.ItalsotriestoanalyzetheprospectofSino-USspacecooperationinPresidentTrump'sterm.

简介：

简介：

简介：

简介：

简介：EnergyPerformanceContractingwasintroducedintoChinainthemid1990s.SincewesternenergyservicecompaniescametoChina,theirmanagementpatternhasundergonemajorchanges.Whydidsuchchangesoccur?MainlybecausethesecompaniesencounteredtwodifficultiesinChina:taxandfinancing.

简介：

简介：Thispaperdescribespathre-planningtechniquesandunderwaterobstacleavoidanceforunmannedsurfacevehicle（USV）basedonmulti-beamforwardlookingsonar（FLS）.Near-optimalpathsinstaticanddynamicenvironmentswithunderwaterobstaclesarecomputedusinganumericalsolutionprocedurebasedonanAalgorithm.TheUSVismodeledwithacircularshapein2degreesoffreedom（surgeandyaw）.Inthispaper,two-dimensional（2-D）underwaterobstacleavoidanceandtherobustreal-timepathre-planningtechniqueforactualUSVusingmulti-beamFLSaredeveloped.Ourreal-timepathre-planningalgorithmhasbeentestedtoregeneratetheoptimalpathforseveralupdatedframesinthefieldofviewofthesonarwithaproperupdatefrequencyoftheFLS.Theperformanceoftheproposedmethodwasverifiedthroughsimulations,andseaexperiments.Forsimulations,theUSVmodelcanavoidbothasinglestationaryobstacle,multiplestationaryobstaclesandmovingobstacleswiththenear-optimaltrajectorythatareperformedbothinthevehicleandtheworldreferenceframe.Forseaexperiments,theproposedmethodforanunderwaterobstacleavoidancesystemisimplementedwithaUSVtestplatform.TheactualUSVisautomaticallycontrolledandsucceededinitsreal-timeavoidanceagainstthestationaryunderseaobstacleinthefieldofviewoftheFLStogetherwiththeGlobalPositioningSystem（GPS）oftheUSV.