简介：Makingfulluseofwindpowerisoneofthemainpurposesofthewindturbinegeneratorcontrol.Conventionalhillclimbingsearch(HCS)methodcanrealizethemaximumpowerpointtracking(MPPT).However,thestepsizeofHCSmethodisconstantsothatitcannotconsiderbothsteady-stateresponseanddynamicresponse.Afuzzylogicalcontrol(FLC)algorithmisproposedtosolvethisprobleminthispaper,whichcantrackthemaximumpowerpoint(MPP)quicklyandsmoothly.ToevaluateMPPTalgorithms,fourperformanceindicesarealsoproposedinthispaper.Theyaretheenergycapturedbywindturbine,themaximumpower-pointtrackingtimewhenwindspeedchangesslowly,thefluctuationmagnitudeofrealpowerduringsteadystate,andtheenergycapturedbywindturbinewhenwindspeedchangesfast.ThreecasesaredesignedandsimulatedinMATLAB/Simulinkrespectively.ThecomparisonofthethreeMPPTstrategiesconcludesthattheproposedfuzzylogicalcontrolalgorithmismoresuperiortotheconventionalHCSalgorithms.

简介：Aseachtypeofsatellitenetworkhasdifferentlinkfeatures,itsdatatransmissionmustbedesignedbasedonitslinkfeaturestoimprovetheefficiencyofdatatransferring.Thetransmissionofnavigationintegratedservicesinformation(NISI)inaglobalnavigationsatellitesystem(GNSS)withinter-satellitelinks(ISLs)isstudiedbytakingtherealsituationofinter-satellitecommunicationlinksintoaccount.Anon-demandcomputingandbufferingcentralizedroutestrategyisproposedbasedondynamicgroupingandthetopologyevolutionlawoftheGNSSnetworkwithinwhichthesatellitenodesareoperatedinthemannerofdynamicgrouping.Dynamicgroupingisbasedonsatellitesspatialrelationshipsandthegrouproleofthesatellitenodechangesbyturnsduetoitsspatialrelationships.Theroutestrategyprovidessignificantadvantagesofhighefficiency,lowcomplexity,andflexibleconfiguration,bywhichtheestablishedGNSScanpossessthefeaturesandcapabilitiesoffeasibledeployment,efficienttransmission,convenientmanagement,structuralinvulnerabilityandflexibleexpansion.

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简介：BasedontheresearchofChinaandabroad,thisthesiscarriedonanempiricalstudyon272EnglishmajorsusingtheinstrumentofquestionnairesandgainedsomeimportantfindingsthatEnglishmajors’BeliefsaboutTranslationandTheirUseofChineseTranslationasalearningarecloselyrelatedwitheachotherwhichprovedthefindingsofPosenLiao.

简介：Manyglobalemissionreductionstrategieshavebeenproposed,butfewhavebeenassessedquantitativelyfromtheviewofequality,efficiencyandeffectiveness.Integratedassessmentmodels(IAM)isoneoftheeffectivewaystomakeclimatepolicymodeling.SointhispaperwedevelopedtheMRICES(Multi-regionalintegratedmodelofclimateandeconomywithGDPspillovers)model,whichisanIAMbutextendstoincludeGDPspillovermechanism,tomakeassessmentonseveralstrategiesforglobalemissionreduction,includingtheegalitarianismstrategy,theUNDPstrategyandtheCopenhagenAccord.Using1990asabaselineforhistoricalemissionlevels,theegalitarianstrategyarguesthatdevelopedcountriesshouldimplementurgentemissionreductions,whereasdevelopingcountriesareallowedrelativelyhigherfutureemissionquotas.TheUNDPstrategyaddressestheissueofsubstantialchangesinglobaltemperaturebutacknowledgesthatdevelopingcountriesarenotabletoaffordmorecostsformitigationmeasures,whichisinequitablefromtheperspectiveofacountry’srighttodevelop.WealsosimulatedtheCopenhagenAccordtodeterminetheconsequencesbytheyear2100ifeachcountrycontinuestheircurrentemissionmitigationactions,andresultsindicatedthattheincreaseinglobaltemperaturewillbe2.8℃by2100;consequently,muchstrongeremissionreductioneffortsmustbeimplementedafter2020.Basedonanalysisonmitigationstrategies,itisrecognizedthatthecommonbutdifferentiatedresponsibilityprinciplemustbeinsistedwhenmakingglobalmitigationstrategy.Tocomplywiththisprinciple,theemissionreductionbaselineofdevelopedanddevelopingcountriesshouldbediscriminated,so1990and2005canbetakenasthebaseyearfordevelopedanddevelopingcountriesrespectively.

简介：Comparedwithworld’sothergreatpowers,theUnitedStatesdeservestobecalledastatethathasboththedesireandcapabilitytorebuildtheworld.Therefore,itsglobalstrategyhasbecomeveryimportant,andanynationthathasdealingswithWashingtonmusttakethisintoconsideration.However,itismuchdebatablewhethertheUnitedStateshasaglobalstrategy,andwhetheranewglobalstrategyhas

简介：Inthispaper,anonlineardynamicMIMOmodelofa6-DOFunderactuatedquadrotorrotorcraftisderivedbasedonNewton-Eulerformalism.Thederivationcomprisesdeterminingequationsofmotionofthequadrotorinthreedimensionsandseekingtoapproximatetheactuationforcesthroughmodelingoftheaerodynamiccoefficientsandelectricmotordynamics.Thederivedmodelisdynamicallyunstable,soasequentialnonlinearcontrolstrategyisimplementedforthequadrotor.Thecontrolstrategyincludesexactfeedbacklinearizationtechnique,usingthegeometricmethodsofnonlinearcontrol.Theperformanceofthenonlinearcontrolalgorithmisevaluatedusingsimulationandtheresultsshowtheeffectivenessoftheproposedcontrolstrategyforthequadrotorrotorcraftnearquasi-stationaryflight.

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简介：Overthepastdecade,theChinesegovernmenthasdevelopedseveralplansregulationsandpolicymeasuresrelatedtothedevelopmentofrenewableenergytechnologiesandhasimplementedaseriesofpilotprojects.ChinesepolicymakershavespentseveralyearsstudyinghowrenewableenergypolicymodelsthathavebeenusedinternationallycouldbeimplementedinChina.Programsarecurrentlyunderwaytoimplementpilotrenewableportfoliostandards,ormandatorymarketshares(MMS)forrenewableenergy,inseveralprovinces.ThispaperexaminestheprimaryinstitutionsthatareinvolvedinpromotingrenewablepoliciesinChina,thestructureofthepoliciesthatcurrentlyarebeingdrafted,andthestatusofthecomplementary,national-levelrenewableenergylawbeingdraftedtoprovidealegalbasisforongoinglocalandnational-levelpolicies.ItthenexaminesthelegalrequirementsforpromotingrenewableenergylegislationundertheChineselaw-makingsystem.Finally,itprovidesrecommendationsfor

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简介：Code-switchingisasocio-linguisticterm,whichreferstotheswitchingfromonelanguagetoanother.Thispaperattemptstoshowthatcode-switchingcanbeusedasateachingstrategyforsecondlanguageteachingbyillustratingthepossiblereasonsfortheswitching.Italsoexploresthepossibilityofviewingcode-switchingaslanguageinterferenvefromateachingperspective.Inaccordancewiththeseanalysisthispapermakesaconclusionthatwhencode-switchingistocompensateforalanguagecifficultyitmaybeviewedasinterfernceandwhenitisusedasasocio-linguistictoolitbecomesastrategy.

简介：Inthethree-phasetrafficflowstudies,thetrafficflowcharacteristicatthebottlenecksectionisahotspotintheacademicfield.Thecontroversyaboutthecharacteristicsofthesynchronizedflowatbottleneckisalsothemaincontradictionbetweenthethree-phasetrafficflowtheoryandthetraditionaltrafficflowtheory.Undertheframeworkofthree-phasetrafficflowtheory,thispapertakestheon-rampasanexampletodiscussthetrafficflowcharacteristicsatthebottlenecksection.Inparticular,thispapermainlyconductsthemicro-analysistotheeffectoflanechangeunderthetwolaneconditions,aswellastheeffectoftheon-ramponthemainlinetrafficflow.Itisfoundthatwhenthemainroadflowislow,thegreatertheon-rampinflowrate,thehighertheaveragespeedofthewholeroadsection.Astheprobabilityofvehiclesenteringfromtheon-rampincreases,theflowandtheaveragespeedofthemainroadaregraduallystabilized,andthentheon-rampinflowvehiclesnolongerhaveasignificantimpactonthetrafficflow.Inaddition,thispaperfocusesonthevelocitydisturbancegeneratedattheon-ramp,andproposesthecorrespondingon-rampcontrolstrategybasedonit,andthesimulationverifiedthatthecontrolstrategycanreasonablycontrolthetrafficflowbytheon-ramp,whichcanmeetthecontrolstrategyrequirementstosomeextent.

简介：ThispaperpresentsgeneralizedCAPP(G-CAPP)methodwhichdealswithmacroprocessplanningformulti-objectiveintheplanningstageofproductionlineofaccuracywelding(PLAW)basedonthefeaturesofaccuracyweldingproduction(AWP).G-CAPPoffersfoundationsforprototypedesignandgeneralequipmentsorting,productioncapacitypredicationandproductionanalysisbymeansofsimulationandoptimization.Asynthetichierarchyevaluation(SHE)modelforG-CAPPestablishedaccordingtotheplanningobjectiveisutilizedtoestimatethealternateprocessingplansbyusingmembershipfunctionandanalytichierarchyprocess(AHP)ofoperationaltheory.Theassemblyweldinglineofhydraulictorqueconverter(HTC)isasanexampleoftypicalAWPtoexplicateG-CAPPandsyntheticevaluatingstrategyofPLAW.ThefeasibleandrationalprocessconfigurationstrategiesofHTCassemblyweldinglinearepointedoutunderdifferentplanningobjective.

简介：TheSeptember11eventupsetJapan’sdiplomaticagendaandusheredinastrategicrestructuringwiththefocusonanti-terrorismandthetopprioritygiventotieswithWashington.Itsnewdiplomacyagainstterrorstressesthreeaspects:policytowardsWashingtonforensuringstrategiccenterof

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简介：Chinaisoneofthecountrieswiththemostseriousfloodingdisasters.InChina,above70%ofbigcities,50%ofpopulationand75%ofindustrialandagriculturaloutputvaluearedistributedineasterncoastalareaswithseriousflooding.Therefore,enhancementoftheoreticalstudyandexperiencesummarizationofurbanfloodcontrolisofgreattheoreticalandpracticalsignificance.Aseconomyisdevelopingrapidly,urbanscaleisexpandingfast,andurbanfloodcontrolstandispromoted.Urbanfloodcontrolcallsfornewconceptandmethods.Thispapermakesasystematicsummarizationofconceptevolutionandadvancedmethodsconcerningurbanfloodcontrolathomeandabroad.Theconceptofurbanfloodcontrolhastransformedfromsimplefloodcontrolanddrainagetocoexistencewithanduseofflood.Floodcontrolmeasureshavetransferredformemphasisuponengineeringonestoprioritytobothengineeringandnon-engineeringones,withspecialattentiontoecologicalfloodcontrol,suchasmakingfulluseofecologicalrevetment,ecologicalrealignmentofariver,multi-objectivemanagementofurbanflooddetentionregion,turningfloodintoresourcesandutilizationofwetlands.

简介：AbstractA novel bat-origin coronavirus emerged in Wuhan, China in December 2019 and continues to spread across China and the world. At the time of writing, a massive global response has been implemented to control the disease as it spreads from person to person. Yet the high-risk human-wildlife interactions and interfaces that led to the emergence of SARS-CoV and of 2019-nCoV continue to exist in emerging disease hotspots globally. To prevent the next epidemic and pandemic related to these interfaces, we call for research and investment in three areas: 1) surveillance among wildlife to identify the high-risk pathogens they carry; 2) surveillance among people who have contact with wildlife to identify early spillover events; and 3) improvement of market biosecurity regarding the wildlife trade. As the emergence of a novel virus anywhere can impact the furthest reaches of our connected world, international collaboration among scientists is essential to address these risks and prevent the next pandemic.

简介：Mobileplatformdevelopsrapidlyinrecentyears,withitsperformanceandcapacityincreasing.Alargenumberofvirtualrealityapplicationssuchas3Dsimulationandvisualizationhaveappearedonmobileplatform.However,duetorestrictions,suchasthelackofcomputingresourcesandthelimitednetworkbandwidth,thevirtualrealitysystemsonmobileplatformcouldnothavecomparableperformanceastheirpeersondesktopplatform.Takingresourcerestrictionsintoconsideration,trade-offshavebeenmaderegardingthedisplayofvirtualrealitysystems.Weproposeaunifiednetworkschedulingstrategybasedonasynchronousmulti-thread,databasecache,prioritizationandeliminationofoverduerequests.ThisstrategyhasbeentestedontheprototypesystemofvirtualrealitysystemonAndroid.Theresultsdemonstratehighernetworkresourceutilizationandbetteruserexperience.

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