塔式起重機位置優(yōu)化中英文對照外文翻譯文獻

塔式起重機位置優(yōu)化中英文對照外文翻譯文獻塔式起重機位置優(yōu)化中英文對照外文翻譯文獻(文檔含英文原文和中文翻譯)原文：LOCATIONOPTIMIZATIONFORAGROUPOFTOWERCRANESABSTRACT:Acomputerizedmodeltooptimizelocationofagroupoftowercranesispresented.Locationtions.Threesubmodelsarealsopresented.First,theinitiallocationmodelclassifiestasksintogroupsandmentalresultsandthestepsnecessaryforimplementationofthemodelarediscussed.INTRODUCTIONOnlargeconstructionprojectsseveralcranesgenerallyundertaketransportationtasks,particularlywhenasinglecranecannotprovideoverallcoverageofalldemandandsupplypoints,and/orwhenitscapacityisexceededbytheneedsofatightconstructionschedule.Manyfactorsinfluencetowercranelocation.Intheinterestsofsafetyandefficientoperation,cranesshouldbelocatedasfarapartaspossibletoavoidinterferenceandcollisions,ontheconditionthatallplannedtaskscanbeperformed.However,thisidealsituationisoftendifficulttoachieveinpractice;constrainedworkspaceandlimitationsofcranecapacitymakeitinevitablethatcraneareasoverlap.Subsequently,interferenceandcollisionscanoccurevenifcranejibsworkatdifferentlevels.Craneposition(s)tendtobedeterminedthroughtrialanderror,basedonsitetopography/shapeandoverallcoverageoftasks.Thealternativesforcranelocationcanbecomplex,somanagersremainconfrontedbymultiplechoicesandlittlequantitativereference.Cranelocationmodelshaveevolvedoverthepast20years.Warszawski(1973)establishedatime-distanceformulabywhichquantitativeevaluationoflocationwaspossible.FurusakaandGray(1984)presentedadynamicprogrammingmodelwiththeobjectivefunctionbeinghirecost,butwithoutconsiderationoflocation.GrayandLittle(1985)optimizedcranelocationinirregular-shapedbuildingswhileWijesunderaandHarris(1986)designedasimulationmodeltoreconstructoperationtimesandequipmentcycleswhenhandlingconcrete.FarrellandHover(1989)developedadatabasewithagraphicalinterfacetoassistincraneselectionandlocation.ChoiandHarris(1991)introducedanothermodeltooptimizesingletowercranelocationbycalculatingtotaltransportationtimesincurred.Emsley(1992)proposedseveralimprovementstotheChoiandHarrismodel.Apartfromthesealgorithmicapproaches,rule-basedsystemshavealsoevolvedtoassistdecisionsoncranenumbersandtypesaswellastheirsitelayout。AssumptionsSitemanagerswereinterviewedtoidentifytheirconcernsandobservecurrentapproachestothetaskathand.Further,operationswereobservedon14siteswherecraneswereintensivelyused(fourinChina,sixinEngland,andfourinScotland).Timestudieswerecarriedoutonfoursitesforsixweeks,twositesfortwoweekseach,andtwoforoneweekeach.Findingssuggestedinteraliathatfullcoverageofworkingarea,balancedworkloadwithnointerference,andgroundconditionsaremajorconsiderationsindetermininggrouplocation.Therefore,effortswereconcentratedonthesefactors(exceptgroundconditionsbecausesitemanagerscanspecifyfeasiblelocationareas).Thefollowingfourassumptionswereappliedtomodeldevelopment(detailedlater):Geometriclayoutofallsupply(S)anddemand(D)points,togetherwiththetypeandnumberofcranes,arepredetermined.ForeachS-Dpair,demandlevelsfortransportationareknown,e.g.,totalnumberoflifts,numberofliftsforeachbatch,maximumload,unloadingdelays,andsoon.Thedurationofconstructionisbroadlysimilarovertheworkingareas.ThematerialtransportedbetweenanS-Dpairishandledbyonecraneonly.MODELDESCRIPTIONThreestepsareinvolvedindeterminingoptimalpositionsforacranegroup.First,alocationgenerationmodelproducesanapproximatetaskgroupforeachcrane.Thisisthenadjustedbyataskassignmentmodel.Finally,anoptimizationmodelisappliedtoeachtowerinturntofindanexactcranelocationforeachtaskgroup.InitialLocationGenerationModelLiftCapacityand‘‘Feasible’’AreaCraneliftcapacityisdeterminedfromaradius-loadcurvewherethegreatertheload,thesmallerthecrane’soperatingradius.Assumingaloadatsupplypoint(S)withtheweightw,itscorrespondingcraneradiusisr.Acraneisthereforeunabletoliftaloadunlessitislocatedwithinacirclewithradiusr[Fig.1(a)].Todeliveraloadfrom(S)todemandpoint(D),thecranehastobepositionedwithinanellipticalarea(a)FIG.1.FeasibleAreaofCraneLocationforTaskFIG.2.Task“Closenness”enclosedbytwocircles,showninFig.1(b).Thisiscalledthefeasibletaskarea.ThesizeoftheareaisrelatedtothedistancebetweenSandD,theweightoftheload,andcranecapacity.Thelargerthefeasiblearea,themoreeasilythetaskcanbehandled.Measurementof‘‘Closeness’’ofTasksThreegeometricrelationshipsexistforanytwofeasibletaskareas,asillustratedinFig.2;namely,(a)onefullyenclosedbyanother(tasks1and2);(b)twoareaspartlyintersected(tasks1and3);and(c)twoareasseparated(tasks2and3).Asindicatedincases(a)and(b),bybeinglocatedinareaA,acranecanhandlebothtasks1and2,andsimilarly,withinB,tasks1and3.However,case(c)showsthattasks2and3aresofarfromeachotherthatasingletowercraneisunabletohandlebothwithoutmovinglocation;somorethanonecraneorgreaterliftingcapacityisrequired.Theclosenessoftaskscanbemeasuredbythesizeofoverlappingarea,e.g.,task2isclosertotask1thantask3becausetheoverlappingareabetweentasks1and2islargerthanthatfor1and3.Thisconceptcanbeextendedtomeasureclosenessofatasktoataskgroup.Forexample,areaCinFig.2(b)isafeasibleareaofataskgroupconsistingofthreetasks,wheretask5issaidtobeclosertothetaskgroupthantask4sincetheoverlappingareabetweenCandDislargerthanthatbetweenCandE.Iftask5isaddedtothegroup,thefeasibleareaofthenewgroupwouldbeD,showninFigure2(c).GroupingTasksintoSeparatedClassesIfnooverlappingexistsbetweenfeasibleareas,twocranesarerequiredtohandleeachtaskseparatelyifnootheralternatives—suchascraneswithgreaterliftingcapacityorreplanningofsitelayout—areallowed.Similarly,threecranesarerequirediftherearethreetasksinwhichanytwohavenooverlappingareas.Generally,taskswhosefeasibleareasareisolatedmustbehandledbyseparatecranes.Theseinitialtasksareassignedrespectivelytodifferent(crane)taskgroupsasthefirstmemberofthegroup,thenallothertasksareclusteredaccordingtoproximitytothem.Obviously,tasksfurthestapartaregivenpriorityasinitialtasks.Whenmultiplechoicesexist,computerrunningtimecanbereducedbyselectingtaskswithsmallerfeasibleareasasinitialtasks.Themodelprovidesassistanceinthisrespectbydisplayinggraphicallayoutoftasksandalistofthesizeoffeasibleareaforeach.Afterassigninganinitialtasktoagroup,themodelsearchesfortheclosestremainingtaskbycheckingthesizeofoverlappingarea,thenplacesitintothetaskgrouptoproduceanewfeasibleareacorrespondingtotherecentlygeneratedtaskgroup.Theprocessisrepeateduntiltherearenotasksremaininghavinganoverlappingareawithinthepresentgroup.Thereafter,themodelswitchestosearchforthenextgroupfromthepoolofalltasks,theprocessbeingcontinueduntilalltaskgroupshavebeenconsidered.Ifataskfailstobeassignedtoagroup,amessageisproducedtoreportwhichtasksareleftsotheusercansupplymorecranesor,alternatively,changethetasklayoutandrunthemodelagain.InitialCraneLocationWhentaskgroupshavebeencreated,overlappingareascanbeformed.Thus,theinitiallocationsareautomaticallyatthegeometriccentersofthecommonfeasibleareas,oranywherespecifiedbytheuserwithincommonfeasibleareas.TaskAssignmentModelGrouplocationisdeterminedbygeometric‘‘closeness.’’However,onecranemightbeoverburdenedwhileothersareidle.Furthermore,cranescanofteninterferewitheachothersotaskassignmentisappliedtothosetasksthatcanbereachedbymorethanonecranetominimizethesepossibilities.FeasibleAreasfromLastThreeSetsofInputshapeandsizeoffeasibleareas,illustratedinFig.9.Inthiscasestudy,fromthedataandgraphicoutput,theusermaybecomeawarethatoptimallocationsledbytestsets1,2,and3(Fig.3)arethebestchoices(balancedworkload,conflictpossibility,andefficientoperation).Alternatively,inconnectionwithsiteconditionssuchasavailabilityofspaceforthecranepositionandgroundconditionsforthefoundation,siteboundarieswererestricted.Consequently,oneofthecraneshadtobepositionedinthebuilding.Inthisrespect,theoutcomesresultingfromset4wouldbeagoodchoiceintermsofareasonableconflictindexandstandarddeviationofworkload,providedthataclimbingcraneisavailableandthebuildingstructureiscapableofsupportingthiskindofcrane.Otherwise,set5resultswouldbepreferablewiththestationarytowercranelocatedintheelevatorwell,butatthecostofsufferingthehighpossibilityofinterferenceandunbalancedworkloadsOverallcoverageoftaskstendstobethemajorcriterioninplanningcranegrouplocation.However,thisrequirementmaynotdetermineoptimallocation.Themodelhelpsimproveconventionallocationmethods,basedontheconceptthattheworkloadforeachcraneshouldbebalanced,likelihoodofinterferenceminimized,andefficientoperationachieved.Todothis,threesubmodelswerehighlighted.First,byclassifyingallness’’anoveralllayoutisproduced.Second,basedonasetofpointslocatedrespectivelyinthefeasibleareas(initiallocation),thetaskassignmentreadjuststhegroupstoproducenewoptimaltaskgroupswithsmoothedworkloadsandleastpossibilityofconflicts,togetherwithfeasibleareascreated.Finally,optimizationisappliedforeachcraneonebyonetofindanexactlocationintermsofhooktransporttimeinthreedimensions.Experimentalresultsindicatethatthemodelperformssatisfactorily.Inadditiontotheimprovementonsafetyandaverageefficiencyofallcranes,10–40%savingsoftotalhookstransportationtimecanbeachieved.Efforthasbeenmadetomodelthekeycriteriaforlocatingagroupoftowercranes,andtworealsitedatahavebeenusedtotestthemodel.However,itdoesnotcapturealltheexpertiseandexperienceofsitemanagers;otherfactorsrelatingtobuildingstructure,foundationconditions,laydownspacesformaterials,accessibilityofadjoiningpropertiesandsoon,alsocontributetotheproblemoflocations.Therefore,thefinaldecisionshouldbemadeinconnectionwiththesefactors.翻譯：一組塔式起重機的位置優(yōu)化摘要計算機模型能使一組塔機位置更加優(yōu)化。合適的位置條件能平衡工作載荷，降低塔機之間碰撞的可能性，提高工作效率。這里對三個子模型進行了介紹。首先，把初始位置模型分組，根據(jù)幾何的相似性，確認每個塔機的合適位置。然后，調(diào)整前任務(wù)組的平衡工作載荷并降低碰撞的可能性。最后，運用一個單塔起重機優(yōu)化模型去尋找吊鉤運輸時間最短的位置。本文對模型完成的實驗結(jié)果和必要的步驟進行了討論。引言在大規(guī)模的建設(shè)工程中特別是當一個單塔起動機不能全面的完成重要的任務(wù)要求時或者當塔機不能完成緊急的建設(shè)任務(wù)時通常是由幾個塔機同時完成任務(wù)。影響塔機的因素很多。從操作效率和安全方面考慮，如果所有計劃的任務(wù)都能執(zhí)行，應(yīng)將塔機盡可能的分開，避免互相干擾和碰撞。然而這種理想的情況在實踐中很難成功，因為工作空間的限制和塔機的耐力有限使塔機的工作區(qū)域重疊是不可避免的。因此，即使起重機的鐵臂在不同的水平工作面也會發(fā)生互相干擾和碰撞。在地形選址和全面的完成任務(wù)的基礎(chǔ)上，通過反復實驗來決定塔式起重機的合適位置。起重機位置的選擇很復雜，因此，管理人員仍然面臨著多樣的選擇和少量的定量參考。在過去的20年里，起重機位置模型逐步形成。Warszawski(1973)嘗試盡可能用時間與距離來計算塔機的位置。FurusakaandGray(1984)提出用目標函數(shù)和被雇用成本規(guī)劃動態(tài)模型，但是沒考慮到位置。GrayandLittle(1985)在處理不規(guī)則的混凝土建筑物時候，設(shè)置位置優(yōu)化的塔式起動機。然而，WijesunderaandHarris(1986)在處理具體的任務(wù)時減少了操作時間和延長了設(shè)備使用周期時設(shè)計了一種模擬模型。FarrellandHover(1989)開發(fā)了帶有圖解界面的數(shù)據(jù)庫，來協(xié)助起動機的位置的選擇。ChoiandHarris(1991)通過計算運輸所須的全部時間來提出另一種優(yōu)化單塔起重機位置優(yōu)化。Emsley(1992)改進了ChoiandHarris提出的模型。除了在計算方法相似外，起重機的數(shù)量類型和設(shè)計系統(tǒng)規(guī)則也得以提高假設(shè)采訪網(wǎng)站管理員關(guān)于他們的公司和觀察到手上的工作電流的方法。另外觀察起重機集中在14個操作站點的運用。(在中國是4個，在英格蘭是6個，在蘇格蘭是4個)。研究設(shè)備放在4個站點時間為6個星期，兩個站點用兩個星期時間。調(diào)查結(jié)果顯示尤其是在全面覆蓋工作領(lǐng)域，沒有干擾，平衡工作載荷和地面情況是決定塔機位置重要的原因。因此，重點在這些因素上（除了地面情況因為站點管理員能明確說明合適的區(qū)域位置）。下面4種假設(shè)被應(yīng)用于模型發(fā)展（以后的詳盡）預先確定所有供應(yīng)點和需求點的幾何布局、起重機的類型和數(shù)量。對于每個供應(yīng)點和需求點，運輸需求水平是已知的。例如，起重機的總數(shù)、每組起重機的數(shù)量、最大限度的裝載、延遲卸貨等等。在建設(shè)時期和工作區(qū)域大體相同。只用一個起重機運輸供應(yīng)點與需求點之間的物料。模型描述決定起重機理想的位置有三個位置條件。首先用位置模型產(chǎn)生一個相似的任務(wù)組，然后用任務(wù)分配模型調(diào)整，最后優(yōu)化模型輪流并運用到每個任務(wù)組中的準確位置。初始位置生成模型起重機的起升能力和合適的區(qū)域起重機的升起能力取決于曲線的半徑，負荷量越大，起重機的操作半徑越小。假設(shè)供應(yīng)點的負荷量是w,相應(yīng)的起重機半徑是r。一個起重機若不能承受裝載除非它的半徑在圓內(nèi)（圖1）。從供應(yīng)點傳送一個裝載需求點，必須把起重機放在兩個重合的橢圓區(qū)域，如圖表1(b)，這是合適任務(wù)區(qū)域。區(qū)域的大小與供應(yīng)點和需求點的距離、負荷量、起重機的耐力有關(guān)。合當?shù)膮^(qū)域越大，越容易完成任務(wù)。相近任務(wù)的測量對于任何兩種合適的任務(wù)區(qū)域存在3種幾何關(guān)系，如圖解2.也就是說，(a)一個圖與另個圖完全重合（任務(wù)1與2）。(b)兩個區(qū)域部分相交（任務(wù)1與3）。（c）兩個區(qū)域分開（任務(wù)2與3）。如指出的實例a與b,起重機被放在區(qū)域A中能完成任務(wù)1和任務(wù)2，同樣的，在區(qū)域B中,能完成任務(wù)1和3.然而實例c顯示，任務(wù)2和3距離太遠，一個單獨的起重機在沒有移動位置的