简介:TheeconomicbenefitsandoptimalrotationageofLarixkaempferipulpwoodplantationwereanalyzedunderstochasticpulpwoodpriceusingrealoptionsapproachinordertomoreeffectivelymanagementtoL.kaempferipulpwoodplantationinnorthernsub-tropicalalpinearea.Flexiblerotationageandthresholdpricetodifferentstandageofdifferentsiteindexplantationweredeveloped.Theresultindicatedthat:1)theoptimalrotationageofL.kaempferiplantationinsiteindex15,17,19,21was25,23,21and19a,respectively,asthecurrentpulpwoodpriceequals500yuan·m-3,andtheshortestrotationagewas23,20,17and15awhenfacingtobetterprice;and2)Waitoptionshouldbetheoptimumstrategyinanypulpwoodpricelevelwhenthestandageislowerthantheshortestrotationage.
简介:Powerefficiencyandlinkreliabilityareofgreatimportanceinhierarchicalwirelesssensornetworks(HWSNs),especiallyatthekeylevel,whichconsistsofsensornodeslocatedonlyonehopawayfromthesinknodecalledOHS.ThepowerandadmissioncontrolprobleminHWSNsiscomsideredtoimproveitspowerefficiencyandlinkreliability.Thisproblemismodeledasanon-cooperativegameinwhichtheactiveOHSsareconsideredasplayers.Byapplyingadouble-pricingschemeinthedefinitionofOHSs'utilityfunction,aNashEquilibriumsolutionwithnetworkpropertiesisderived.Besides,adistributedalgorithmisalsoproposedtoshowthedynamicprocessestoachieveNashEquilibrium.Finally,thesimulationresultsdemonstratetheeffectivenessoftheproposedalgorithm.
简介:WiththeincomeincreaseofelderlypeopleinBeijingandtheimprovementofleisurefacilitiessince2000,thequalityofelderlypeopleleisurelifeinBeijinghasobviouslyincreasedcomparedtotenyearsago.Accordingtotheinvestigationandcomparativeanalysisonmorethan900elderlypeople,whousuallyexerciseinpublicparksinBeijingCity,wehavefoundoutseveralnewfeaturesofelderlypeople’soutdoorrecreationinBeijing:theincreaseoftheleisuretime,theexpansionofleisurespace,theindividuationofinterestandthediversificationofconsumption.Theleisurelifequalityevaluationindexsystemofurbanelderlypeoplecanbebuiltbasedontheseanalyses.Inordertoaccommodatethedevelopmenttendencyofelderlypeople’sdemandforleisurediversification,weshouldstrengthentheorganizationandmanagementofelderlypeople’sleisureactivityinurbanconstruction,andpaymoreattentiontofunctioncomplementationbetweencommunitiesandparks.
简介:Anewformationnavigationapproachderivedfrommulti-robotscooperativeonlineFastSLAMisproposed.Inthisapproach,theleaderandfollowerrobotsaredefined.Theposterioriestimationoftheleaderrobotstateistreatedasarelativereferenceforallfollowerrobotstocorrecttheirstateprioriestimations.Thecontrolvolumeofindividualfollowerwillbeachievedfromtheresultsofthecorrectedestimation.Allrobotsareobservedaslandmarkswithknownassociationsbytheothersandareconsideredintheirlandmarksupdating.Bythemethod,theerrorsoftherobotposteriorestimationsarereducedandtheformationiswellkept.Thesimulationandphysicalexperimentresultsshowthatthemulti-robotsrelativelocalizationaccuracyisimprovedandtheformationnavigationcontrolismorestableandefficientthannormalleader-followingstrategy.Thealgorithmiseasyinimplementation.
简介:Thespring(March-April-May)rainfallovernorthernChina(SPRNC)ispredictedbyusingtheinterannualincrementapproach.DYdenotesthedifferencebetweenthecurrentyearandpreviousyears.TheseasonalforecastmodelfortheDYofSPRNCisconstructedbasedonthedatathataretakenfromthe1965-2002period(38years),inwhichsixpredictorsareavailablenolaterthanthecurrentmonthofFebruary.Thisisfavorablesothattheseasonalforecastscanbemadeonemonthahead.Then,SPRNCandthepercentageanomalyofSPRNCareobtainedbythepredictedDYofSPRNC.Themodelperformswellinthepredictionoftheinter-annualvariationoftheDYofSPRNCduring1965-2002,withacorrelationcoefficientbetweenthepredictedandobservedDYofSPRNCof0.87.Thisaccountsfor76%ofthetotalvariance,withalowvaluefortheaveragerootmeansquareerror(RMSE)of20%.Boththeresultsofthehindcastfortheperiodof2003-2010(eightyears)andthecross-validationtestfortheperiodof1965-2009(45years)illustratethegoodpredictioncapabilityofthemodel,withasmallmeanrelativeerrorof10%,anRMSEof17%andahighrateofcoherenceof87.5%forthehindcastsofthepercentageanomalyofSPRNC.
简介:ObjectiveToinvestigatetheclinicaloutcomesoffacialneverdecompressionviaacombinedsubtemporal-supralabyrinthineapproachtogeniculateganglionformanagementoffacialparalysisintemporalbonefracture.MethodsEighteenpatientswithunilateralfacialparesisduetotemporalbonefractureweretreatedbetweenMarch2003andMarch2011.FacialfunctionwasHouse-Brackmann(HB)gradeⅢin6patients,HBgradeⅤin9patientsandHBgradeⅥin3patients.Thepreoperativemeanairconductionthresholdwas52dBHLforthe15caseswithlongitudinaltemporalbonefractureandshowedseveresensorineuralhearinglossinthe3caseswithtransversetemporalbonefracture.Fracturelinesweredetectedin15casesontemporalboneaxialCTscansandossiculardisruptionwasdeterminedin11casesbyvirtualCTendoscopy.Thegeniculateganglionorthetympanicmastoidsegmentofthefacialnerveshowedanirregularmorphologyoncurvedplanarreformationimagesofthefacialnervecanal.Afteranintactcanalwallmastoido-epitympanectomy,theossicularchaindamagewasevaluated.Iftheossicularchainwasintact,thesupralabyrinthinerecesswasopenedbydrillingthroughthecellsbetweenthetegmentympaniandossicularchain.Iftheossicularchainwasdisrupted,theincuswasremovedtoaccessthesupralabyrinthinerecess.Thegeniculateganglionandthedistallabyrinthinesegmentofthefacialnervewereexposed.Aftercompletingfacialnervedecompression,thedislocatedincuswasreplaced,orafracturedincuswasreshapedtobridgethespacebetweenthemalleusandthestapes.ResultsPronouncedgangliongeniculatumswellingwasfoundin15casesoflongitudinaltemporalbonefracture,withgreaterpetrosusnervesdamagein3casesandbleedingin5cases.Disruptedossicularchainswereseenin11cases,includingdislocatedincusresultingincrushingofthehorizontalportionofthefacialnervein3casesandfractureoftheincuslongprocessin1case.In3casesoftransversefractures,
简介:Thegeometryofaninductivelycoupledplasma(ICP)etcherisusuallyconsideredtobeanimportantfactorfordeterminingbothplasmaandprocessuniformityoveralargewafer.Duringthepastfewdecades,theseparametersweredeterminedbythe'trialanderror'method,resultinginwastesoftimeandfunds.Inthispaper,anewapproachofregressionorthogonaldesignwithplasmasimulationexperimentsisproposedtoinvestigatethesensitivityofthestructuralparametersontheuniformityofplasmacharacteristics.ThetoolforsimulatingplasmaisCFD-ACE+,whichiscommercialmulti-physicalmodelingsoftwarethathasbeenproventobeaccurateforplasmasimulation.Thesimulatedexperimentalresultsareanalyzedtogetaregressionequationonthreestructuralparameters.Throughthisequation,engineerscancomputetheuni-formityoftheelectronnumberdensityrapidlywithoutmodelingbyCFD-ACE+.Anoptimizationperformedattheendproducesgoodresults.
简介:Apeer-to-peer(P2P)networkisadistributedapplicationarchitecturewhichprovidesmanyattractivefeatures,suchasavailability,self-organization,load-balancing,andanonymity.However,P2Pnetworkhascreatedsignificantproblemstonetworkoperatorsbygeneratinglargevolumesofinterautonomoussystem(inter-AS)traffic.FocusingontheBitTorrentswarmingprotocol,thispaperproposesanapproachwhichaimstoreduceP2Pgeneratedinter-AStraffic.Inparticular,theapproachcanreduceinter-AStrafficby50%to70%.Moreover,itcanimprovethedownloadingspeedby60%forthepopulartorrents.Theevaluationshowsthatcontrolledregional-basedcontentsreplicationcaneffectivelyachievethisgoal.Furthermore,theapproachisincrementallydeployable.NetworkregionsinwhichthesystemgetsdeployedcansolvetheirP2Pgeneratedinter-AStrafficproblemsautonomously,i.e.,withoutanyInternetserviceproviders-collaborationandanyrequirement,thesystemcanbedeployedintheentireInternet.
简介:ThispaperstudiestheinfinitetimehorizonmixedH-two/H-infinitycontrolproblemfordescriptorsystemsusingNashgameapproach.Anecessary/sufficientconditionfortheexistenceofinfinitehorizonH-two/H-infinitycontrolispresentedintheformoftwocoupledalgebraicRiccatiequations,respectively.Finally,asuboptimalH-two/H-infinitycontrollerdesignisgivenbasedonaniterativelinearmatrixinequalityalgorithm.
简介:Inthispaper,ananalyticaltechniqueispresentedfortimedomainanalysis(transientandsteady-stateresponse)ofperturbedPWMpush-pullDC-DCconverterusinginterestingcorollaryonKharitonov'stheorem.ThemainadvantageoftheproposedanalysisisthateventhoughthetransferfunctionmodelofaPWMpush-pullDC-DCconverterisperturbed,thecompleteanalysishasbeendoneonalineartransferfunctionmodelofaPWMpush-pullDC-DCconverter.TheproposedanalysisisverifiedusingMATLABsimulation.Thisanalysiswillbeverymuchusefultopowerelectronicsengineers,sincethetechniqueisverysimpleandcomputationallyefficientandeasilyapplicableinpreciseapplicationssuchasaerospaceapplications.