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/外文文獻翻譯（譯成中文1000字左右）：【主要閱讀文獻不少于5篇，譯文后附注文獻信息，包括：作者、書名（或論文題目）、出版社（或刊物名稱）、出版時間（或刊號）、頁碼。供應所譯外文資料附件（印刷類含封面、封底、書目、翻譯部分的復印件等，網(wǎng)站類的請附網(wǎng)址及原文】ShipsTypedAccordingtoMeansofPhysicalSupportThemodeofphysicalsupportbywhichvesselscanbecategorizedassumesthatthevesselisoperatingunderdesignedconditions.Shipsaredesignedtooperateabove,on,orbelowthesurfaceofthesea,sotheair-seainterfacewillbeusedasthereferencedatum.Becausethenatureofthephysicalenvironmentisquitedifferentforthethreeregionsjustmentioned,thephysicalcharacteristicsofshipsdesignedtooperateinthoseregionscanbediverse.AerostaticSupportTherearetwocategoriesofvesselsthataresupportedabovethesurfaceoftheseaonaself-inducedcushionofair.Theserelativelylightweightvehiclesarecapableofhighspeeds,sinceairresistanceisconsiderablylessthanwaterresistance,andtheabsenceofcontactwithsmallwavescombinedwithflexiblesealsreducestheeffectsofwaveimpactathighspeed.Suchvesselsdependonliftfanstocreateacushionoflow-pressureairinanunderbodychamber.Thiscushionofairmustbesufficienttosupporttheweightofthevehicleabovethewatersurface.Thefirsttypeofvesselhasflexible“skirts”thatentirelysurroundtheaircushionandenabletheshiptorisecompletelyabovetheseasurface.Thisiscalledanaircushionvehicle(ACV),andinalimitedsenseitisamphibious.Theothertypeofair-cushioncrafthasrigidsidewallsorthinhullsthatextendbelowthesurfaceofthewatertoreducetheamountofairflowrequiredtomaintainthecushionpressure.Thistypeiscalledacaptured-air-bubblevehicle(CAB).Itrequireslesslift-fanpowerthananACV,ismoredirectionallystable,andcanbepropelledbywaterjetsorsupercavitatingpropellers.Itisnotamphibious,however,andhasnotyetachievedthepopularityoftheACVs,whichincludepassengerferries,cross-channelautomobileferries,polar-explorationcraft,landingcraft,andriverinewarfacevessels.HydrodynamicSupportTherearealsotwotypesofvesselsthatdependondynamicsupportgeneratedbyrelativelyrapidforwardmotionofspeciallydesignedhydrodynamicshapeseitheronorbeneaththesurfaceofthewater.Aprincipleofphysicsstatesthatanymovingobjectthatcanproduceanunsymmetricalflowpatterngeneratesaliftforceperpendiculartothedirectionofmotion.Justasanairplanewith(airfoil)producesliftwhenmovingthroughtheair,ahydrofoil,locatedbeneaththesurfaceandattachedbymeansofasurfacepiercingstrut,candynamicallysupportavessel’shullabovethewater.PlanninghullsarehullformscharacterizedbyrelativelyflatbottomsandshallowV-sections(especiallyforwardofamidships)thatproducepartialtonearlyfulldynamicsupportforlightdisplacementvesselsandsmallcraftathigherspeeds.Planningcraftaregenerallyrestrictedinsizeanddisplacementbecauseoftherequiredpower-to-weightratioandthestructuralstressesassociatedwithtravelingathighspeedinwaves.Mostplanningcraftarealsorestrictedtooperationsinreasonablyclamwater,althoughsome“deepV”hullformsarecapableofoperationinroughwater.HydrostaticSupportFinally,thereistheoldestandmostreliabletypeofsupport,hydrostaticsupport.Allships,boats,andprimitivewatercraftuptothetwentiethcenturyhavedependedupontheeasilyattainedbuoyantforceofwaterfortheiroperation.Thishydrostaticsupport,commonlyrecognizedasflotation,canbeexplainedbyafundamentalphysicallawthattheancientphilosopher-mathematicianArchimedesdefinedinthesecondcenturyB.C.Archimedes’Principlestatesthatabodyimmersedinaliquidisbuoyedup(oractedupon)byaforceequaltotheweightoftheliquiddisplaced.Thisprincipleappliestoallvesselsthatfloat(orsubmerge)inwatersaltorfresh.Andfromthisstatementthenameoftheshipsinthecategoryarederived;theyaregenerallycalleddisplacementhulls.Althoughthisshiptypeisveryfamiliar,itssubcategorieswarrantspecialdiscussion.Forexample,insomevesselsreasonablyhighspeedmustbecombinedwiththeabilitytocarrylightcargoortomovemorecomfortablyinroughwaterthanaplanninghull.High-speedplanning-hullcharacteristicscanbemodifiedtoproduceasemidisplacementhullorsemiplaninghull.Thesecompromisecraft,ofcoursenotasfastasfull-planinghullsbutfasterthanconventionaldisplacementhull,musthavemorepowerandlessweightthanthelatter.Suchtypesareobviouslytheresultof“tradeoffs.”Theexamplecitedaboveliesbetweenclear-cutphysicallydefinedcategoriesitisnotagoodexampleofavariationofatruedisplacement-typeship.Thelattermustberecognizedprimarilyasadisplacementvessel,anditsvariationsdependprimarilyonthedistributionofbuoyantvolumetheextentofthedepthandbreadthofthehullbelowthewater.Themostubiquitoustypeofdisplacementshipcanbegenerallyclassifiedasthecommoncarrier,aseagoingvessel.Itmaybeemployedforpassengerservice,lightcargo-carrying,fishingbytrawlingorforhundredsofothertasksthatdonotrequireexceptionalcapacity,speed,submergence,orotherspecialperformance.Itisthemostcommonandeasilyrecognizabletypeofship,withmoderatedisplacement,moderatespeeds,moderatetolargelengths,andmoderatecapacities.Itusuallyembodiesthemaximumincruisingrangeandseaworthiness.Itisthe“shipforallseasons.”Itisthestandardtowhichallothershipclassificationsinthedisplacementcategorymaybereferred.Theclosestrelativetothisstandardvessel,whichplaysacrucialrolenotonlyinworldcommercebutinthesurvivaloftheindustrialworldaswell,isthebulk,oilcarrier,thetanker,orsupertanker.Theseterminologiesarecommonbutunspecific,andinthisdiscussiontheyareinadequate,forwhatwascalledasupertankerseveralyearsagoistodaynotasupertanker.Theindustryitselfhascreatedafarmoreexplicitnomenclature.Basedupontheindexof1000000tonsoilcargocapacity,thesizecategoriesareLCC(largecrudecarrier),VLCC(verylargecrudecarrier),andULCC(ultralargecrudecarrier).Anytankergreaterthan100000tonsbutlessthan200000isaLCC,thosebetween200000and400000areVLCCs,andthoseover400000areULCCs.Thecurrentnecessityforthesedesignationsbecomesclearwhenwerealizethatbefore1956therewerenotankerslargerthan50000tons,andnotuntiltheearlysixtieswereanyshipsbuiltlargerthan100000tons.In1968thefirstshipover300000tonswasbuilt.Withtheirbulkandenormouscapacity(fourfootballfieldscanbeplacedendtoendononeoftheirdecks),theseshipsaredesignedandbuilttobeprofit-makers,enormouslylong,wide,anddeep,carryingthousandsoftonsofcrudeoilpervoyageattheleastcost.Fewoftheseelephantinetankershavemorethanonepropellershaftofrudder.Theirnavigationbridgesarenearlyonequarterofamilefromtheirbows.TheirtopservicespeedissolowthatavoyagefromanArabianoilporttoaEuropeandestinationnormallytakestwomonths.Suchvesselsbelongtoacategoryofdisplacementshipthathasagreatrangeofbuoyantsupport.Theyhaveaverylargeanddisproportionatehullvolumebelowthesurfacewhenfullyloaded.Indeed,thecargoweightfarexceedstheweightoftheshipitself.ThedraftordepthofwaterrequiredforafullyloadedVLCCrunsto50or60feetandtheULCCmaybe80feet.Suchshipsbelongintheexclusivecategoryofdisplacementvesselscalleddeepdisplacementships.Thereexistsanothertypeofdisplacementhullwithextremedraft.However,itissimilaritytothecrude-oilcarrieroftheprecedingdiscussiongoesnofurtherthanthat.ThistypeofvesseliscalledtheSWATH(smallwaterplaneareatwinhull).Briefly,thisratherrarebreedofshipisdesignedforrelativelyhighspeedandstableplatforminmoderatelyroughwater.Itsfutureisproblematical,butthetheoryofplacingthebulkofthedisplacementwellbelowthesurfaceandextendingthesupporttotheabove-waterplatformordeckthroughthenarrowwaterlinefinsorstrutsissound.Twinhullsconnectedbyanupperplatformprovidethenecessaryoperatingstability.Themostsignificantclassofdisplacementhullforspecialapplicationisthesubmarine,avesselforcompletelysubmergedoperation.Thenatureofthesubmarineandadescriptionofhervariousoperationalattitudes,bothstaticanddynamic,iscoveredinsubsequentchapters.ItisonlynecessaryheretoemphasizethatsubmerisiblevesselsarespecificallydisplacementvesselsapplyingthetheoryofArchimedes’Principleandallthatitimplies.MultihullVesselsThereisoneothertypeofhullincommonusethathasnotyetbeenmentioned,primarilybecauseitfitsintononeofthecategoriesdescribedbutrathercanexistcomfortablyinany.Thiscraftistheso-calledmultihullvesselthecatamaranandthetrimaran.Thesevesselsaremostfrequentlydisplacementhullsintheirlargersizes,suchastheSWATHmentionedabove,ormoreconventionally,oceanresearchvesselsrequiringstableplatformsandprotectedareasforlaunchingequipment.Therearealsothetwin-hulledCABvesselsmentionedearlierandhigh-speedplanningcatamarans.Actually,themultihullshipisanadaptationofanyofthebasichullcategoriestoaspecialapplicationthatrequiresexceptionaltransversestabilityand/ortheinterhullworkingarea.中文翻譯：依據(jù)物理支撐方式而劃分的船舶類型就船舶分類而言，物理支撐形式是基本于船舶在設計狀況下進行的假定。船舶設計成在水上、水面或者水下工作，因此氣—水交界面將用于參考數(shù)據(jù)。因為前面提到的三個區(qū)域的物理環(huán)境特性差異很大，設計成在這些區(qū)域工作的船舶的物理特性也不同?？諝忪o力支撐有兩種類型船舶是靠前身產(chǎn)生的空氣墊而支撐在海面之上的。這些相對較輕的船舶具有很高的航速，因為空氣阻力遠小于水阻力，還有的緣由是在告知航行時不和海浪接觸以及接受的柔性密封連接削減了海浪的沖擊。這類船舶依靠鼓風機在船底部形成一個低壓空氣墊。這個空氣墊必需足以支撐起水上船舶的重量。第一種類型船的四周具有柔性的“裙”，在船底圍成一個空氣墊，試船能完全升離水面。這種船成為“氣墊船”（ACV），再有些場合是兩棲的。另外一種是具有剛性側壁或薄殼的氣墊型船，側壁伸到水面下，維持氣墊壓力所需的空氣流量就降低了。這種類型的船稱為束縛氣泡減阻船（CAB）。這種船所需的升力風機功率要小于氣墊船的，方向穩(wěn)定性也更好，并可以由噴水裝置或者超空泡螺旋槳推動。此類船非兩棲，并且還沒有達到像空氣船那樣推廣，如旅客渡船、海峽汽車渡船、極地考察船、登陸艇及內(nèi)河船等。水動力支撐依靠水動力支撐的船也只有兩種類型。水動力是靠特地設計的水動力板在水面下具有快速相對運動而產(chǎn)生的。物理學原理表明任何帶來不對稱流體的運動物體都會在垂直于運動的方向上產(chǎn)生一個升力。正像具有機翼的飛機在空氣中運動能產(chǎn)生升力一樣，通過一個穿過水面的支柱而固定在水下的木翼，其水動力可以支撐一般船舶離開水面。滑行船體的特點是具有相對平坦的底部和淺V型剖面（特殊是在船中前），高速航行時在局部可以為輕排水量船和小型船艇供應足夠的水動力支撐?；型У某叽绾团潘恳话愣际芟拗疲驗楣β手亓勘群驮诓ɡ酥泻叫挟a(chǎn)生的結構應力大小都有要求。大多數(shù)滑行艇都要求在靜水中航行，盡管某些深V型船體具有再波浪中航行的實力。靜水力支撐最終，是最古老的也是最牢靠地支撐類型——靜水力支撐。始終到20世紀，全部的船、艇和建議的水艇都依靠靜水的浮力而工作在水面上。靜水力支撐通常稱為浮力，可以由公元前二世紀古代哲學及數(shù)學家阿基米德發(fā)覺的物理定律來說明。阿基米德定律指出，浸沒在液體中的物體將受到一個等一所排開的液體重量的浮力作用。這確定律適用于浮在水面或在下潛到水中的任何船。水包括海水和淡水。依據(jù)這確定律，這類船可以統(tǒng)稱為排水型船。盡管這類船特殊相像，其詳細分類還是有必要進行特殊探討。例如，對某些船，合理的高航速必需和裝載輕量貨物的實力相結合，或者比滑行艇在波浪中航行更具舒適性。高速滑行船體的特點可以通過修改而產(chǎn)生半排水型船體或半滑行船體。這些折中的船艇，盡管沒有全滑行船那樣快，但還是比常規(guī)的排水型船快。它們須要比排水型船更大的功率和更小的重量。這些類型船很明顯是“折中”的結果。上面引證的例子是用物理定義作清晰分類而定義的類型，并不是從其實的排水型船中分化出的船型的一個良好的例子。后者應當認為是排水型船，它的歸類主要取決于浮體體積即水下船體長度和寬度范圍的分布狀況。最常見的是排水型船一般分類為通用海洋運輸船，它們可以用作客運、輕貨運輸、拖網(wǎng)捕魚或各種不須要特殊艙容、速度、吃水、或其它特殊性能的其他業(yè)務。這類船最常見并很簡潔識別，具有