Page 52 - 2024年第55卷第1期
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suspendedsedimenttransportinthelowerreachesisreducedsignificantly,andconditionsofwaterandsediment
changeobviously,whichhasasignificantimpactonthereservoirsedimentationprocessandmakestheroleofpeb
blebedloadmoreimportantinthetotalsedimenttransport.Therefore ,itisofgreatofsignificancetocarryoutthe
lawofpebblebedloadtransportinthelowerreachesoftheJinshaRiverundernewwaterandsedimentconditions,
andtoputforwardtheapplicableincipientvelocityandtransportrateofpebblebedload.Basedonthemeasured
dataatSanduiziHydrologicalStationfrom2008to2021,theclassicalincipientvelocityformulaandbedloadtrans
portrateformulaaretestedandcorrected.Theresultshowsthatcomparedwithclassicalformulae,thecalculation
accuracyofthemodifiedformulaissignificantlyimprovedbyintroducingacoefficientwiththeparticlesizeasavari
able ,whichinducesdifferentparticlesizeranges.Meanwhile,theresultsofclassicalbedloadtransportratedevi
ategreatlyfromthemeasuredvalueswhenthesedimenttransportintensityislow.Byestablishingtheintensityrela
tionship ofsedimenttransportand waterflow and introducinghidden parameterstomodified formula , the
calculationaccuracyoflowsedimenttransportrateisalsoobviouslyimproved.Thetransportlawofpebblebedload
inSanduizireachcanbedmoreeffectivelyreflectedbythemodifiedformulaeofincipientvelocityandbedload
transportrate.
Keywords:lowerreachesofJinshaRiver;cascadereservoir;pebblebedload;incipientvelocity;pebblebed
loadtransportrate
(责任编辑:李福田)
(上接第 34页)
Anintelligentextractionmethodoftunnelconstructionactivity
durationinformationbasedonimprovedHT - LCNN
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XIAOYao,ZHONGDenghua,YUjia,HUYike,XUGuoxin,CHENQiutong
(1.StateKeyLaboratoryofHydraulicEngineeringIntelligentConstructionandOperation,TianjinUniversity,Tianjin 300072,China;
2.CollegeofWaterResourcesandCivilEngineering,ChinaAgriculturalUniversity,Beijing 100083,China;
3.Hanjiang - to - WeiheRiverValleyWaterDiversionProjectConstructionCo.,Ltd.,ShaanxiProvince,Xi’an 710302,China)
Abstract:Extractionofactivitydurationinformationisimportantforscheduleanalysisanddecisionoftunnelcon
struction.AcommonwaytorecordtheactivitydurationsoftunnelconstructionisdrawingthelinesegmentasGa
nttchartintheconstructionlog.However,thetraditionalextractionmethodthatreliesonmanualstatisticsisfa
cingadilemmabetweenefficiencyandaccuracy.Tosolvethisproblem,thispaperadoptsalinesegmentdetec
tionmethodbasedondeeplearning.Anautomaticextractionmethodoftunnelconstructionactivitydurationinfor
mationbasedonimprovedHoughTransform - LineConvolutionalNeuralNetwork(HT - LCNN)isproposed.First,
thepreprocessingisbasedonhomographytosolvetheobliquity,rotationandtwistoftheoriginalphotos.Second,
theglobalcontextnetwork(GCNet),whichhastheabilityofestablishingthelong - distancedependenceofthe
featuregraphandthedependencebetweenchannels ,isintegratedintotheresidualmoduleofHT - LCNNtoim
provethemodel ’sattentiontothetargetlinesegmentofGanttchart,reducetheinterferencefrom thelineseg
mentofthetableandtext ,andimprovethedetectionaccuracy.Third,thecoordinatesofdetectedlinesareauto
maticallyconvertedintoconstructionactivitydurations.Theproposedmethodisusedtoextracttheactivitydura
tionsofaTBM diversiontunnelprojectfrom17monthsofconstructionlogs.Thecasestudyshowsthatthedetec
tionprecisionAP 5 ,AP 10 andAP 15 are94.7%,95.0% and95.1% respectively,whicharehigherthantheresults
ofHT - LCNNandLCNN.Comparedwithmanualextractionresults ,themeanabsoluteerrorofourautomaticex
tractionmethodisonly1.82min.Thisstudyprovidesanovelideaforextractionoftunnelconstructionactivitydu
rationinformationaccuratelyandefficiently.
Keywords:durationoftunnelconstructionactivities;informationintelligentextraction;linesegmentdetection;
deepnetworkwithHoughtransform;attentionmechanism
(责任编辑:李福田)
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