简介：根据国家有关标准规定，凡更新地形图，都必须以新的图幅编号方法表示。而第一代地形图一律以旧式图幅编号方法表示为了方便新旧图号的互相检索，本文介绍了有关互换的数学模型，列举了互换例子，并据此编制了互换程序软件，可供各有关生产单位和组织生产部门参考使用

简介：针对传统分类方法精度不高、感兴趣目标分类不理想等缺陷，采用多特征组合的支持向量机影像分类方法，利用颜色矩、颜色集和灰度共生矩阵进行特征提取，总体精度、Kappa系数和混淆矩阵作为评价指标对单一特征、组合特征的不同分类结果进行分析。实验结果表明，该方法有效地解决了单数据源分类不完整、精度低等问题，对高维输入向量具有较高的推广力。

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简介：-Driftcurrentinducedbywindandwavesisinvestigatedwithphase-averagedNavier-StokesequationinwhichtheReynoldsstressisclosedbyk-εmodel.Thegoverningequationsaresolvedbythefinitevolumemethodinasystemofnonorthogonalcoordinateswhichisfittedtothephase-averagedwavesurface.Thepredicteddriftcurrentisfairlyreasonableandthedragcoefficientofsea-surfacepredictedwiththenewlydevelopedinterfaceconditionsshowsgoodagreementwithpreviousmeasurementswhenbreakingwavesdonotexist.

简介：Mooringmodelexperimentandmooringlinetensiondeterminationareofsignificancetothedesignofmooringsystemsandberthingstructures.Thispapermainlyinvolves:(a)descriptionandanalysisofamooringmodelexperiment;(b)derivationofstaticequilibriumequationsforamooredshipsubjectedtowind,currentandwaves;(c)solutionofmo.oringequationswiththeMonteCarlomethod;(d)qualitativeanalysisofeffectsofpierpilesonmooringlineforces.Specialemphasisisplacedonthederivationofstaticequilibriumequations,solutionmethodandthemooringmodelexperiment.

简介：ThecircumfluencearoundtheJiuduanSandbankisthoroughlystudiedbymeansoftheprinci-pleofleastresistanceinfluiddynamics.ThediversionratiooftheNorthChannelfor1998iscalculated,whichisalmostthesameasthefieldsurveydata.ThenormalandminimumdiversionratiosoftheNorthChannelafterstagesⅠ,ⅡandⅢregulationworksaswellasthefuturephaseareobtained.Thenumeri-calresultsandpredictedvalueareaccurate.

简介：Themethodhasbeenestablishedtocalculatetheenvironmentalcapacity(ECo),surplusenvironmentcapacity(SECo)ofwaterwithrespecttomarinepetroleumhydrocarbonsassociatedwithoil(PHAOs)andtheself-purificationcapacity(SPCo)ofmainself-purificationprocesstoPHAOsintheJiaozhouBay,China,accordingtothedynamicmodelfordistributionofmarinePHAOsamongmultiphaseenvironments.ThevariationofconcentrationofPHAOsintheJiaozhouBayiswellsimulatedbythedynamicmodel.Basedonthemodel,theEC.,SEC.ofwaterwithrespecttoPHAOsintheJiaozhouBaywerecalculatedduringthelast10yearsunderthefirst-classandsecond-classqualitystandardrequirement,accordingtoSPCoofmainself-purificationprocesstoPHAOs.Theresultsshowthatabout200tonsofPHAOscouldbedischargedintotheJiaozhouBayformaintainingthefirstclassseawaterqualitystandard,andabout600tonsofPHAOsforthesecondclassseawaterqualitystandardlater.

简介：ＣａｌｃｕｌａｔｉｏｎｏｆｂｖａｌｕｅａｎｄｉｔｓａｐｐｌｉｃａｔｉｏｎｉｎｅａｒｔｈｑｕａｋｅｐｒｅｄｉｃｔｉｏｎＨｕａ－ＣｈｅｎＤＵＡＮ（段华琛）；Ｃｈａｎｇ－ＱｉｎｇＦＡＮ（范长青）ａｎｄＹｕｅ－ＭｉｎＸＵ（许跃敏）（Ｓｅｉｓｍｏｌｏｇｉｃａｌ...

简介：2012年7.21特大暴雨期间,香山街道公主坟15号院边坡出现垮塌并造成了破坏,边坡亟需治理。本文介绍了该边坡的基本特征,分析了边坡的变形情况及影响因素并确定了边坡的破坏模式,并选用瑞典圆弧法评价了边坡的稳定性。根据边坡的实际情况,选择了适于土质边坡防治的新型支挡加固措施一格构锚固工程,并辅以挡土墙工程及绿化工程,作为边坡治理的工程措施。

简介：Thecurrentcalibrationfunctionusedincalculatingthemagnitudeofnaturalearthquakeswithin5kmisaconstant;afactthatcausesseveralseriousdifficultiesforthecalculationofthemagnitudeofsmallandshallow-focusearthquakes.Accordingtotheattenuationlawofexplosionsandthepropagationtheoryofelasticwaves,thecalibrationfunctioniscalculatedfornearfieldquakesfrom0kmto5km.Magnitudesoftwoaftershocksequencesarecalculated.Themagnitudesofmostexplosionearthquakesaresmall,rangingmainlyfrommagnitude0.5to1.0.TheM-tchartoftheexplosiveaftershocksiscompletelydifferentfromthatofstrongearthquakeaftershocks.Itnotonlyshowspositivecolumnarlinesindicatinglargemagnitudesbutalsoshortnegativecolumnarlinesindicatingsmallmagnitudes.

简介：Thehollow-pipeperforatedbreakwaterisoflowreflection.Inthispaperthefunctionsofreflectioncoefficientsofbothregularandrandomwavesaretheoreticallyderived,basedontheconceptoflinearsuperimpositionofreflectedandincidentwavesandwiththetotalflowratecontinuityofintegralforminsteadofthenon-continuityoftheboundarycondition,andbasedontheconceptoflinearwavespectrumtheory.Comparisonsbetweentheoreticalresultspresentedhereandmeasurementsofmodeltestsshowreasonableagreement.

简介：Thispaperconcernsthecalculationofthewavetroughexceedanceprobabilitiesinanonlinearsea.Thecalculationshavebeencarriedoutbyincorporatingasecondordernonlinearwavemodelintoanasymptoticmethod.Thisisanewapproachforthecalculationofthewavetroughexceedanceprobabilities,and,asallofthecalculationsareperformedintheprobabilitydomain,avoidstheneedforlongtime-domainsimulations.TheproposedasymptoticmethodhasbeenappliedtocalculatethewavetroughdepthexceedanceprobabilitiesofaseastatewiththesurfaceelevationdatameasuredatthecoastofYuraintheJapanSea.ItisdemonstratedthattheproposednewmethodcanofferbetterpredictionsthanthetheoreticalRayleighwavetroughdepthdistributionmodel.ThecalculatedresultsbyusingtheproposednewmethodhavebeenfurthercomparedwiththoseobtainedbyusingtheArhanandPlaistednonlineardistributionmodelandtheToffolietal.’swavetroughdepthdistributionmodel,anditsaccuracyhasbeenonceagainsubstantiated.Theresearchfindingsobtainedfromthisstudydemonstratethattheproposedasymptoticmethodcanbereadilyutilizedintheprocessofdesigningvariouskindsofoceanengineeringstructures.

简介：【摘要】G.D包装机一号轮在设备运行过程中，烟支组与护烟板时刻都在发生磨擦现象，护烟板磨损严重时，会造成烟支触头等问题，护烟板前端与轮体的中心距离为130mm，因难以测量护烟板前端与轮体中心之间的距离，所以会增加更换和安装护烟板工作的难度。所以如何缩短维修时间和减少零部件损坏成了最需要解决的问题。

简介：Standingwavesareformedduetothereflectionwhenwavesmeetverticalwall,thereforestrongstructuresareneededtokeepthewallstabilityundertheseriouswaveattack.Fortheimprovementoftheworkingconditionandincreaseofthestabilityofthewall,thelowerreflectingbreakwatershaveat-tractedcloseattentionReportsmostlyfromJapaneseresearchersareoftenconcernedwiththewallofcaissonequippedwithopenwindows.Inthispaperakindofhollow-pipeperforatedbreakwaterisexam-inedwhichwavesmaypartiallyperforateintotheharbourbasin.Thewaveinfrontofthewallcanonlyformpartialstandingwaveandwaveforceisreducedobviously.Andthetheoreticalcalculationofwaveforceandanalysisofwaveforcespectrumareallderived.Comparisonbetweentheresultsfromtheoreticalcalculationandhydraulicmodelingshowsreasonableagreement.

简介：Usinggeographicinformationsystemtostudyfloodedareaanddamageevaluationhasbeenahotspotinenvironmentaldisasterresearchforyears.Inthispaper,amodelforfloodedareacalculationanddamageevaluationispresented.Floodingisdividedintotwotypes:‘sourceflood'and‘non-sourceflood'.Thesource-floodareacalculationisbasedonseedspreadalgorithm.Theflooddamageevaluationiscalculatedbyoverlayingthefloodedarearangewiththematicmapsandrelatingtheresulttoothersocialandeconomicdata.Toraisetheoperationalefficiencyofthemodel,askippingapproachisusedtospeedseedspreadalgorithmandallthematicmapsareconvertedtorasterformatbeforeoverlayanalysis.Theaccuracyoffloodedareacalculationanddamageevaluationismainlydependentupontheresolutionandprecisionofthedigitalelevationmodel(DEM)data,upontheaccuracyofregisteringallrasterlayers,anduponthequalityofeconomicinformation.ThismodelhasbeensuccessfullyusedintheZhejiangProvinceComprehensiveWaterManagementInformationSystemdevelopedbytheauthors.TheapplicationsshowthatthismodelisespeciallyusefulformostcountiesofChinaandotherdevelopingcountries.

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简介：Withthedevelopmentofhigh-resolutionandmulti-scaleunifiednumericalmodel,someoftechniquesaboutnon-hydrostaticmeso-scalenumericalweatherpredictionareaddressed.Theimpactoftheverticalcoordinatesystemisoneofthem.Inthispaper,basedonaWRF(WeatherResearchandForecast)model,theimpactonthecalculationofverticalvelocitywasstudiedwithdifferentverticalcoordinates.Thesimulationresultsshowedthatthecalculationofverticalvelocityissensitivetoverticalcoordinates.Itisespeciallymoreevidentwhentheresolutionincreased.Duetothecloserelationshipsbetweenverticalvelocityandprecipitation,thedifferenceofverticalvelocityinevitablyinfluencesmodel'sdescriptionofprecipitation.Anidealexperimentexhibitsthatpressuregradientforcecomputationsinthepressureterrain-followingcoordinatearesensitivetosurfacepressure.

简介：Onthebasisofasinusoidalmodelofthedisturbedhorizontalacceleration,thespectrumcharacteristicsofmisalignedangleandhorizontalaccelerationcorrectionareanalyzed.Inanairbornegravimetrytest,themisalignedangleofplatformandhorizontalaccelerationcorrectionarecalculated.Theyare5'and3mGal,respectively,whentheflightisstable.

简介：［1］Copeland,G.J.M.,1985.PracticalRadiationStressCalculationsConnectedwithEquationsofWavePropagation,CoastalEngineering,9,195～219.［2］DINGPingxing,KONGYazhenandSHIFengyan,1998.RadiationStressofWaterWavesandItsCalculation,JournalofEastChinaNormalUniversity,(1):82～87.(inChinese)［3］Kirby,J.T.andDalrymple,R.A.,1983.AParabolicEquationfortheCombinedRefraction-DiffractionofStokesWavesbyMildlyVaryingTopography,J.FluidMech.,136,453～466.［4］Kirby,J.T.,1986a.RationalApproximationsintheParabolicEquationMethodforWaterWaves,CoastalEngineering,10,355～378.［5］Kirby,J.T.,1986b.OpenLateralBoundaryConditionforApplicationintheParabolicEquationMethod,J.WaterwayPort.CoastalEng.,ASCE,112,460～465.［6］Longuet-Higgins,M.S.andStewart,R.W.,1960.ChangesintheFormofShortGravityWavesonLongWavesandTidalCurrents,J.FluidMech.,8,565～583.［7］Longuet-Higgins,M.S.andStewart,R.W.,1961.TheChangesinAmplitudeofShortGravityWavesonSteadyNon.uniformCurrents,J.FluidMech.,10,529～549.［8］Longuet-Higgins,M.S.andStewart,R.W.,1962.RadiationStressandMassTransportinGravityWaveswithApplicationtoSurfBeats,J.FluidMech.,13,481～504.［9］Longuet-Higgins,M.S.andStewart,R.W.,1964.RadiationStressinWaterWaves:aPhysicalDiscussionwithApplications,Deep-SeaRes.,11,529～562.［10］Longuet-Higgins,M.S.,1970.LongshoreCurrentsGeneratedbyObliquelyIncidentSeaWaves,J.Geophys,Res.,75,6778～6801.［11］Noda,E.K.,1974.Wave-InducedNearshoreCirculation,J.Geophys.Res.,79,4097～4106.