简介:Basedontheassumptionofglobalsealevelrisingbetween30and100cminthefuture100yearsbyIPCC(1990)inadditiontotheeffectoflocalgroundsubsidence,thecoastlinewillretrogradefor50-70kmwhosealtitudeswillbe2.6-3.3maboveMSLofHuanghaiSeainthewesterncoastalareaoftheBohaibayin2100.Thetransgrassiveareaisabout10,000-11,500km.Iftheeffectofset-upofstormsurgeisconsidered,thetransgressiveareawillreach16,000km.Sealevelrisewhichisaseriouscoastaldisasternotonlyinundatesalotofcoastallowland,butalsoincreasesthefrequencyandintensityofstormtides,andresultsinthesalinizationofsoils.Inviesofthissituationwerecommendatrinitycomprehensivemeasureoftreatment,namely,"buildingseawalltopreventtides-divertingtheHunagheRivertosettleitssedimentloads-raisingtheconstructionalbase".
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简介:Onthebasisofthedressed-atommodel,thegeneralanalyticexpressionsfortheeigenenergies,eigenstatesandtheiropticalpotentialsoftheA-configurationthree-levelatomsystemarederivedandanalysed.Fromthecalculationofdipolematrixelementofdifferentdressedstates,weobtainthespontaneous-emissionratesinthedressed-atompicture.Wefindthatourgeneralexpressionsofopticalpotentialsforthethree-leveldressedatomcanbereducedtothesameasonesinpreviousreferencesundertheapproximationofasmallsaturationparameter.Wealsoanalysethedependencesoftheopticalpotentialsofathree-level^85Rbatomonthelaserdetuningandthedependencesofspontaneous-emissionratesontheradialpositioninthedarkhollowbeam,anddiscusstheprobability(population)evolutionsofdressed-atomiceigenstatesinthreelevelsinthehollowbeam.
简介:Knowledgeabouthumanbeingsisanintegralpartofanyintelligentagentofconsiderablesignificance.Delimiting,modelingandacquiringsuchknowledgearethecentraltopicsofthispaper.Becauseofthetremendouscomplexityinknowledgeofhumanbeings,weintroduceatop-levelontologyofhumanbeingsfromtheperspectivesofpsychology,sociology,physiologyandpathology.Thisontologyisnotonlyanexplicitconceptualizationofhumanbeings,butalsoanefficientwayofacquiringandorganizingrelevantknowledge.
简介:Thispaperstudiesthelinkageproblembetweentheresultofhigh-levelsynthesisandback-endtechnology,presentsamethodofhigh-leveltechnologymappingbasedonknowledge,andstudiesdeeplyallofitsimportantlinkssuchasknowledgerepresentation,knowledgeutilityandknowledgeacquisition.Itincludes:(1)presentakindofexpandedproductionaboutknowledgeofcircuitstructure;(2)presentaVHDL-basedmethodtoacquireknowledgeoftechnologymapping;(3)providesolutioncontrolstrategyandalgorithmofknowledgeutility;(4)presentahalf-automaticmaintenancemethod,whichcanfindredundanceandcontradictionofknowledgebase;(5)presentapracticalmethodtoembedthealgorithmintoknowledgesystemtodecreasecomplexityofknowledgebase.Asystemhasbeendevelopedandlinkedwiththreekindsoftechnologies,soverifiedtheworkofthispaper.
简介:本文阐述了基于形变模型(DeformableModels)的LevelSet分割方法的基本原理及其特点,介绍了在图像域的实现方法,实现并改进了基于该模型的NarrowBand快速算法.该算法的基本流程是:先在需要分割的目标内或外给定一封闭的初始曲线,通过Gaussian滤波后计算图像的梯度,最后通过NarrowBand算法完成轮廓线的抽取.该算法应用于医学CT/MRI影像以及显微图像的目标分割中,取得了较好的实验结果,证明该方法非常适合于对具有分支、突触以及拓扑结构变化的目标进行快速精确分割.文中给出了算法实现的基本流程、相关参数的选取准则和部分实验结果.实验发现算法中涉及的参数对提取的轮廓线的精确和光滑程度有较大影响.
简介:StandardmetabolicratesofSchlegelsblackrockfishwithdifferentbodyweightsaredeterminedinlaboratorybyusingtheflow-throughrespirometerat11.2℃,14.7℃,18.0℃and23.6℃.Theresultsindicatethatthestandardmetabolicratesincreasewiththeincreaseofbodyweightatdifferenttemperatures.RelationshipbetweenthemcouldbedescribedasRs=aInWb.Themeanofstandardmetabolicrateissignificantlydifferentamonggroups,butthebvaluesarenot.Thestandardmetabolicratesofamendedstandardbodyweightsdecreasewiththeincreaseoftemperature,andthemeanofstandardmetabolicrateisalsosignificantlydifferentamonggroupswhenthestandardbodyweightsare48.6g,147.9g,and243.1g.RelationshipbetweenthemcouldbedescribedasRsw=me-bT.Therelationsofstandardmetabolicrate(Rs)orrelativemetabolicrate(Rs)tobodyweightandtemperatureyieldthefollowingequations:Rs=1.160W0.752e-9.494/7andRs1=1.160W0.254e-9.494/7.
简介:应用根系喷雾箱(RootMistingChamber,RMC)形成的5次干旱循环,通过PV曲线的水分参数研究了多重复干旱循环对1年生北美短叶松PinusbanksianaLamb.和黑云杉Piceamariana[Mil]B.S.D.苗木耐旱特性的影响.结果表明,生长在干旱沙地的深根性树种北美短叶松,其丧失膨压的相对含水量(8076%~8141%)和水势((-174±010)MPa)都比较低,细胞弹性模量(573~652MPa)比较小,而束缚水含量(5272%~5426%)比较高,显示出它固有的强有力的忍耐脱水能力;但是在多重复干旱循环下它却不能进一步调节其渗透势和细胞弹性,而且其束缚水含量和吸水能力也有所下降.生长在湿润地区的浅根性树种黑云杉,虽然其丧失膨压的相对含水量(8353%~8550%)和水势((-168±003)MPa)比较高,细胞弹性模量(862~964MPa)比较大,束缚水含量(3644%~4605%)比较低,显示出较弱的耐旱能力,但是它在多重复干旱循环下却能提高其束缚水含量以改善原生质耐旱程度,降低细胞弹性以提高其吸水能力,调节其渗透势以保持较高的膨压.这表?
简介:Besidesofconsideringofthemaximizationofpublicinterest,thebenefitofpassengersandrailwayenterprisesarebothconsideredandabi-levelprogrammingapproachispresentedinordertoseektheoptimalrailwaypassenger-ticketpricingstrategyundertheconditionofcompetitionamongdifferentintercitytrafficmodes.Therearetwobi-levelprogrammingproblems.Onebi-levelproblemistodeterminearailwaypassenger-ticketaveragepricestrategytomeet.theobjectiveofmaximizingtheconsumersurplusundertheconditionofmulti-modaltransportationwithelasticdemand.Theotherbi-levelproblemistodeterminethepriceofdifferentkindsofthepassengertrainstomeettheobjectiveofmaximizingtherailwayrevenuewheretheaveragepriceandthedemandoftherailwayisdetermined.Aheuristicalgorithmforthetwobi-levelprogrammingmodelsisalsoproposed.Finallytheapplicationsofthemodelanditsalgorithmareillustratedwithanumericalexample.
简介:Storingthewholedatabaseinthemain-memoryisacommonmethodtoprocessreal-timetransactioninreal-timedatabasesystems.TherecoverymechanismofMain-memoryReal-timeDatabaseSystems(MMRTDBS)shouldreflectthecharacteristicsofthemain-memorydatabaseandreal-timedatabasebecausetheirstructuresarequitedifferentfromotherconventionaldatabasesystems.Inthispaper,therefore,weproposeamulti-levelrecoverymechanismformain-memoryreal-timedatabasesystemswithExtendibleChainedBucketHashing(ECBH).Owingtotheoccurrenceofreal-timedatainreal-timesystems,weshouldalsoconsideritinourrecoverymechanism.Accordingtoourperformancetest,thismechanismcanimprovethetransactionconcurrency,reducingtransactions'deadlinemissingrate.
简介:Thedynamicalframeworkofthenine-levelversionoftheIAPAGCMispresentedinthispaper.Theemphasisofthemodel’sdescriptionisputonthefollowingtwoaspects:(1)Amodel’sstandardatmosphere,whichisasatisfactoryapproximationtotheobservedtroposphereandlowerstratospherestandardatmosphere,isintroducedintotheequationsofthemodeltopermitamoreaccuratecalculationoftheverticaltransportterms,especiallynearthetropopause;(2)Theverticallevelsofthemodelarecarefullyselectedtoguaranteeasmoothdependenceoflayerthicknessuponpressureinordertoreducethetruncationerrorinvolvedintheunequalintervalverticalfinite-differencing.Fortestingthemodel,twokindsoflinearbaroclinicRossby-Haurwitzwaves,oneofwhichhasadynamicallystableverticalstructureandtheotherhasarelativelyunstableone,areconstructedtoprovideinitialconditionsfornumericalexperiments.Thetwowaveshavebeenintegratedformorethan300daysand100daysre