简介：Intrusiondetectioncanbeessentiallyregardedasaclassificationproblem,namely,dis-tinguishingnormalprofilesfromintrusivebehaviors.Thispaperintroducesboostingclassificationalgorithmintotheareaofintrusiondetectiontolearnattacksignatures.Decisiontreealgorithmisusedassimplebaselearnerofboostingalgorithm.Furthermore,thispaperemploysthePrincipleCom-ponentAnalysis(PCA)approach,aneffectivedatareductionapproach,toextractthekeyattributesetfromtheoriginalhigh-dimensionalnetworktrafficdata.KDDCUP99datasetisusedintheseex-perimentstodemonstratethatboostingalgorithmcangreatlyimprovetheclassificationaccuracyofweaklearnersbycombininganumberofsimple“weaklearners”.Inourexperiments,theerrorrateoftrainingphaseofboostingalgorithmisreducedfrom30.2%to8%after10iterations.Besides,thispaperalsocomparesboostingalgorithmwithSupportVectorMachine(SVM)algorithmandshowsthattheclassificationaccuracyofboostingalgorithmislittlebetterthanSVMalgorithm’s.However,thegeneralizationabilityofSVMalgorithmisbetterthanboostingalgorithm.

简介：Modernnetworksystemshavemuchtroubleinsecurityvulnerabilitiessuchasbufferoverflow,bugsinMicrosoftInternet,sensornetworkroutingprotocoltoosimple,securityflawsofapplications,andoperatingsystems.Moreover,wirelessdevicessuchassmartphones,personaldigitalassistants(PDAs),andsensorshavebecomeeconomicallyfeasiblebecauseoftechnologicaladvancesinwirelesscommunicationandmanufacturingofsmallandlow-costsensors.Therearetypologiesofvulnerabilitiestobeexploitedinthesedevices.Inordertoimprovesecurities,manymechanismsareadopted,includingauthentication,cryptography,accesscontrol,andintrusiondetectionsystems(IDS).Ingeneral,intrusiondetectiontechniquescanbecategorizedintotwogroups:misusedetectionandanomalydetection.Themisusedetectionsystemsusepatternsofwell-knownattacksorweakspotsofthesystemstoidentifyintrusions.Theweaknessofmisusedetectionsystemsisunabletodetectanyfuture(unknown)intrusionuntilcorrespondingattacksignaturesareintrudedintothesignaturedatabase.Anomalydetectionmethodstrytodeterminewhetherthedeviationisfromtheestablishednormalusagepatternsornot.Thecriticalsuccessofanomalydetectionreliesonthemodelofnormalbehaviors.

简介：通常一个维(1-D)实验咸度侵入模型被限制到自然冲积河口。然而，这研究试图调查它的能力在马来西亚为Terengganu河的一个掩盖的冲积河口建模。在河的嘴的构造防波提从公海的直接影响掩盖河口。沿着河口的咸度密度被收集在期间湿并且为在构造防波提前后的情形的旱季。而且，淡水分泌物，潮汐的举起和深测术数据也作为模型输入被测量。一好合适在模仿并且观察的变量之间被表明，也就是为两种情形的咸度分发和侵入长度。因此，结果显示出那1-D实验咸度模型能在Terengganu河口为掩盖的河口状况被利用，但是与一个起始的点的一颗适当决心。而且，在学习区域的咸度侵入大部分依赖于淡水分泌物而非潮汐的举起变化，这被观察。在学习区域的咸度侵入长度的规模与the-1/2力量的河分泌物成正比。实验咸度模型和分泌物驱动的1-D的二根线基于适合很好到对方的方程，这被显得，与150的平均预言的最小的淡水分泌物，m3/s将被要求在水吸入车站附近在高水位线呆滞(HWS)期间维持可接受的咸度层次，它从河嘴在10.63km被定位。

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简介：Thesimulationofthisprocessandtheeffectsofprotectionirojectslaysthefoundationofitseffectivecontrolanddefence.Themathematicalmodeloftheproblemandupwindsplittingalternatingdirectionmethodwerepresented.Usingthismethod,thenumericalsimulationofseawaterintrusioninLaizhouBayAreaofShandongProvivcewasfinished.Thenumericalresultsturnedouttobeidenticalwiththerealmeasurements,sothepredictionoftheconsequencesofprotectionprojectectsisreasonable.

简介：AsetofdiscretepointsobtainedfromauditrecordsonabehaviorsessionisprocessedwithFouriertransform.ThecriterionofselectingFouriertransformcoefficientsisintroduced,andisusedtofindaunifiedvaluefromthesetofcoefficients.Thisunifiedvalueiscomparedwithathresholdtodeterminewhetherthesessionisabnormal.Finallysimpletestresultsarereported.

简介：Predictingpotentialchangesingroundwatersalinityinlow-lyingcoastalregionsduetoclimatechangeisimportant,wherecoastalvegetationisabundant,successioncompetitionbetweenhalophytesandglycophytesplaysasignificantroleinthesalinitybudget.Sealevelriseenhancessalinityintrusion,contributinganadditionaldimensiontovegetationcompetition.Anewsimulationmodelknownasmangrove-hardwoodhammockmodelcoupledwithsaturated-unsaturatedtransport(MANTRA)hasrecentlybeendevelopedbytheauthorstosimulategroundwatersalinityregimesinthepresenceofvegetationcompetition,subjecttoclimatechange.MANTRAisbaseduponlinkingtwoexistingUnitesStatesgeologicalsurvey(USGS)simulationmodelsknownasmangrove-hardwoodhammockmodel(MANHAM)andsaturated-unsaturatedtransport(SUTRA).MANHAMsimulatestheevolutionofvegetationsuccessionsubjecttochanginggroundwatersalinity.SUTRAsimulatessaturatedandunsaturatedtransportofsolutesandsalinityingroundwatergivenseasalinity.MANTRAimprovesthesimulationrobustnesstosimultaneouslysimulategroundwaterhydrology,salinityandcoastalvegetationsuccessionsubjecttosealevelrise.Somesimulationresultswillbepresentedtodemonstratetheimpactofsealevelriseoncoastalvegetationsuccessionandgroundwatersalinity.

简介：Thispaperpresentsanewmethodbasedonasecond-orderstochasticmodelforcomputerintrusiondetection.Theresultsshowthattheperformanceofthesecond-orderstochasticmodelisbetterthanthatofafirst-orderstochasticmodel.Inthisstudy,differentwindowsizesarealsousedtotesttheperformanceofthemodel.Thedetectionresultsshowthatthesecond-orderstochasticmodelisnotsosensitivetothewindowsize,comparingwiththefirst-orderstochasticmodelandotherpreviousresearches.Thedetectionresultofwindowsizes6and10isthesame.

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简介：Greyself-organizingmap(GSOM)modelisproposedandappliedinthedetectionofintrusion.ThroughtheimprovementoftheweightadjustmentusingtheGRC(greyrelationalcoefficient),thetrainingresultsofSOMgetbetter.Inthedetectionofdenyofservice(DOS)attacks,thismodelcanconsidertherelativityofthedatasetofDOSattacks.Finally,theexperimentsontheDOSdatasetconfirmtheirvaliditiesandfeasibilitiesoverthisGSOMmodel.

简介：Basedontheone-dimensionalsalinitytransportequationwithconstantdiffusioncoefficient,andseparatedwaterflowvelocityintorunoffandtidalcurrentwiththesingle-frequencyinanidealizedestuary,thesimplestunsteadyanalyticalsolutionofsalinityintrusionisdeducedandtheestimationformulaofdiffusioncoefficientisobtainedinthispaper.Theunsteadysolutionindicatesthatsalinityprocessinestuariesresultsfromtheinteractionofrunoffandtidalcurrent,anditsamplitudeisindirectproportiontotheproductofthevelocityofrunoffwaterandtheamplitudeoftidalflowvelocityandininverseproportiontothediffusioncoefficientandthetidalangularfrequency,anditsphaselagtidalflowwithπ/2whichrevealsthebasicfeaturesofthemaximumsalinityappearingafterfloodslackandtheminimumsalinityappearingbeforeebbslackundertheeffectofrunoff(theadvanceorlagtimeisrelativetothemagnitudeofrunoffandtidalflow).Accordingtothemeasuredflowvelocityandsalinitydata,thesalinitydiffusioncoefficientcouldbeestimated.Finally,withthefielddataofobservingsitesonthedeepwaternavigationchanneloftheYangtzeEstuary,thediffusioncoefficientiscalculatedandacomparativeanalysisofsimulatedandmeasuredofsalinityprocessismade.Theresultsshowthatthesolutioncancomprehensivelyreflectsthebasiccharacteristicsandprocessesofsalinityintrusionundertheinteractionofrunoffandtidalflowinestuaries.Thesolutionisnotonlysuitablefortheoreticalresearch,butalsoconvenientforestimatingreasonablephysicalparametersandgivingtheinitialconditioninthesalinityintrusionnumericalsimulation.

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简介：盐水的侵入在最近的年里的珍珠河河口是严肃的。为到河口的盐水的运动的更好的理解和分析，三维的有限卷的沿海的海洋模型(FVCOM)被做在三个半月形的条件下面在珍珠河河口模仿咸度侵入到四条西方的水路。与测量并且模仿的根均方差(RMSE)和在多重地点，数字水铺平的结果表演，咸度和流动的水水平和咸度的吝啬的绝对百分比错误，速度与测量数据一致。使用FVCOM模仿盐水侵入在可接受、可行西方珀尔河的四条水路。与数字数据，时间和沿着Modao水路的盐水的侵入的空间运动模式被分析。咸度轮廓在春天潮前在35天期间通常到达它的山峰。咸度层化在时期是更明显的退潮比那在升起的潮是否在春天或小潮潮。盐流动思考进河口的盐的变化，和变化规则接近咸度侵入的规则。

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简介：Porestructurecharacteristicsofrockareagreatconcernforresearchersandpractitionersinrockmechanicsandrockengineeringfields.Inthisstudy,mercuryintrusionporosimetry（MIP）wasusedtomeasureporesizedistribution,aswellasseveralimportantindexparametersofporestructure,forsevencommontypesofdeepsedimentaryrockswithatotaloffiftyrocksamples.Resultsshowasimilarporesizedistributionpatternoftherocksamplesinthesamelithologicalgroup,butremarkabledifferencesamongdifferentlithologicalgroups.Amongseveninvestigatedrocktypes,mudstonehasthesmallestporosityof3.37%,whileconglomeratehasthelargestvalueof18.8%.Itisalsofoundthattheporosityofrocktypeswithfinergrainsizeislowerthanthosewithcoarsergrainsize.Meanwhile,acomparisonoffrequencydistributionattenintervalsofpore-throatdiameteramongseventypesofsedimentaryrocksrevealsthatdifferentrocktypeshavedifferentdominantpore-sizeranges.Furthermore,permeabilityoftheinvestigatedsedimentaryrocksampleswasderivedbasedonMIPdatausingreportedtheoreticalequations.Amongsevenrocktypes,mudstonehasthelowestaveragedpermeability(3.64×10-6mD)whileconglomeratehasthehighestone(8.59×10-4mD).Frommudstonetoconglomerate,rockpermeabilityincreaseswithanincreaseofgrainsize,withonlyanexceptionofsiltstonewhichhasarelativelylargerporosityvalue.Finally,regressionanalysisshowthatthereisagoodfitting（R2=0.95）betweenpermeabilityandporositywhichcouldbeeasilyusedtoderivereliablepermeabilityvaluesofsimilarkindsofengineeringrocks.