《交通工程专业英语》(19)-Unit19 Economics and Transportation Engineering

TextEnglishforTrafficEngineeringUnit19EconomicsandTransportationEngineeringEconomicsandTransportationEngineeringAneconomicanalysisshouldnotbecarriedoutasanafterthought.Itshouldbeusedaspartofacontinuousprocess,startingwiththeobjectivesoftheproposedtransportationproject(cantheseobjectivesbesatisfiedinanyotherway?),runningthroughtheentireplanninganddesignprocess,andonlyending,asafinalsummingup,withtheoverallevaluation.Itshouldconsiderthefollowingquestions:(1)Projectidentification.(2)Establishingroughpriorities.(3)Detailedevaluation.(4)Projectselection.Shouldthisprojectbeselected,shoulditberejected,orshoulditbepostponed?afterthought[ˈɑːftəθɔːt]identification[aɪˌdentɪfɪˈkeɪʃn]priority[prəɪˈɔrəti]postpone[pəˈspəun]

n.事后的想法；后来添加的东西n.鉴别；识别；认同n.优先；优先权；[数]优先次序；优先考虑的事vt.使……延期；把……放在次要地位vi.延缓；延迟EconomicsandTransportationEngineeringEconomicsisoftenoverlookedasanaidtotransportationplanninganddesign.Yetanytrafficengineeringprobleminvolvesawholeseriesofessentiallyeconomicdecisions.Arivercrossingcouldthusbebyferryboat,causewayorbridge.Inthelattercase,itcouldbeinsteel,concreteortimber.Itcouldbesuspended,arched,orsimplysupported.Therangeofchoiceisnotusuallyaslargeasthis.Somesolutionswillbephysicallyinfeasible,butimportantchoiceswillremain.Intheabsenceofarigorouseconomicanalysis,thedesignersmaymakethesechoicesonthebasisof:(1)Experience,whichmayormaynotcoveranadequaterangeofoptions.(2)Preconceptionsastowhatisdesirable.ferry[ˈferi]causeway[ˈkɔːzweɪ]timber[ˈtɪmbə(r)]suspend[səˈspend]infeasible[ɪnˈfɪzəbl]rigorous[ˈrɪgərəs]preconception[priːkənˈsepʃn]

n.渡船；摆渡；渡口vi.摆渡；(乘渡船)渡过n.堤道；公路n.（建筑等用的）木材；木料vt.延缓，推迟；使暂停；使悬浮vi.悬浮；禁赛adj.不能实行的adj.严格的；严厉的；严酷的；严峻的n.预想；预见EconomicsandTransportationEngineering(3)Aninnateviewofmathematicalorstructuralelegance(e.g.,anarchisamoreelegantstructuralform).Economicsavoidstheneedforthesearbitraryrulesbyprovidingatangiblecriterion-costforchoosingbetweenalternativesolutions.Inmanycasesthiscanbedonequitesimplybydrawingenvelopeofcostcurvesof,forexample,steelgirderbridgesversusreinforcedconcretebridgesversusprestressedconcretebridges.Byplottingcost(y)againstspanlength(x)theengineerscanchoosewhichtypeismosteconomicoveragivenrangeofspanlengths.innate[ɪˈneɪt] elegance[ˈelɪgəns]arbitrary[ˈɑːbɪtrərɪ]curve[kʒːv]versus[ˈvʒːsəs]prestressed[priːˈstrest]plotting[ˈplɔtɪŋ]

adj.固有的；天生的；天然的；内在的n.高雅；典雅；优雅；雅致adj.任意的，随意的；武断的；独裁的；专断的n.曲线；弯曲物vt.使弯曲vi.弯曲prep.对（指诉讼、比赛中），与……相对adj.预应力的（混凝土）n.测绘；标图EconomicsandTransportationEngineeringInpractice,theengineersdonotusuallycarrytheeconomicanalysistothislevelofdetail,althoughcurveslikethiscommonlyformpartofthestandardhighwaydesignrepertoire.Itisthisgeneralprinciplewhicheventuallyensuresthatthefinaldesignisthemosteconomicalandtheonewhich,ifjustifiedinaggregateterms,offersbestvalueformoney.EconomicefficiencyanddistributionEconomicsisnotconcernedsolelywiththeoptimumallocationofresources,butwithwiderquestionsofequityandthedistributionofcostsandbenefitsamongindividuals,regions,etc.Itisthusconcernedwiththequestions:whodoeswhat,towhom,andatwhoseexpense?repertoire[ˈrepətwɑː(r)]principle[ˈprɪnsəpl]aggregate[ˈæɡrɪɡət]allocation[ˌæləˈkeɪʃn]region[ˈriːdʒən]n.全部节目；全部剧目n.原则；原理；准则n.合计集料adj.总数的；总计的n.分配；配给n.地区；区域；地方；行政区EconomicsandTransportationEngineeringInasense,thisconcerncomplementstheintertemporalconsiderationsnotedabove.Adollartoonepersonisnotnecessarilyworththesameamounttoanother.Sinceeconomicsassumesthatmarginalvaluesdeclineasincomeincreases,interpersonaldifferencesinincomemaythusaffectanyoverallmeasureofconsumerbenefit.Questionsofdistributionneverthelessgobeyondmeredifferencesinincome.Institutionalconstraintsusuallypreventbeneficiaries,definedinthebroadestsense,fromcompensatingpeoplewhoareadverselyaffected.Itisthereforeoftenappropriatetoseparatetheimpactofatransportimprovementintoitseffectondifferentinterestgroups,inadditiontoitseffectondifferentincomegroups.intertemporal[ɪnˈtʒ:rtɪmpərəl]marginal[ˈmɑːdʒɪnl]beneficiary[ˌbenɪˈfiʃəri]appropriate[əˈprəuprɪət]adj.跨时期的adj.小的微不足道的；边的；边缘的；临界的n.[金融]受益人；受惠者；封臣adj.拥有封地的；受圣俸的adj.适当的；恰当的；合适的ExercisesTrueorfalse.Questionsofdistributiongobeyondmeredifferencesinincome.Intheabsenceofarigorouseconomicanalysis,thedesignersmaymaketheirchoices.Allsolutionswillbephysicallyinfeasible.Theengineersusuallycarrytheeconomicanalysistothislevelofdetail.Inmanycasesthiscanbedonequitesimplybydrawingenvelopeofcostcurvesof,forexample,steelgirderbridgeversusreinforcedconcretebridgesversusprestressedconcretebridges.ExercisesCompletethefollowingsentences.Economicsisoftenoverlookedasanaidto__________planninganddesign.Economicsavoidstheneedforthesearbitraryrulesbyprovidingatangiblecriterion-cost-forchoosing__________alternativesolutions.Institutionalconstraintsusuallyprevent__________,definedinthebroadestsense,fromcompensatingpeoplewhoareadverselyaffected.Somesolutionswillbephysicallyinfeasible,__________importantchoiceswillremain.__________usuallypreventbeneficiaries,definedinthebroadestsense,fromcompensatingpeoplewhoareadverselyaffected.ExercisesAnswerthefollowingquestions.Whyeconomicsshouldnotbeoverlookedasanaidtotransportationplanninganddesign?Intheabsenceofarigorouseconomicanalysis,howdothedesignersmakechoices?Howdoeseconomicsavoidtheneedforarbitraryrules?Whatshouldbeconsideredinaneconomicanalysis?Howtochoosethemosteconomictypeoveragivenrangeofspanlengths?ReadingMaterialEnglishforTrafficEngineeringProblemsofBenefit-CostAnalysisProblemsofBenefit-CostAnalysisInagreatmanycountriesbenefit-costanalysisisthepreferred,andinsomecasestherequired,methodofprojectorplanevaluation.Inalltheseanalysesthediscountedstreamofmoneycostsarecomparedwiththediscountedstreamsofbenefitsconvertedintomonetaryterms.Wherebenefit-costratiosinexcessofunityareobtained,theprojectorplanisconsideredworthwhileandwhereanumberofoptionsaretobeevaluated,thatwiththehighestmarginalbenefit-costratioisconsideredpreferable.Extendedsocialbenefit-costanalysisinthepasthasledtocalculationsofgreatcomplexity,butofcoursethevalueofthecalculationsislimitedbytheaccuracywithwhichthenumerousfactorsbeingconsideredcanbequantified.Becausesoveryfewofthesefactorscurrentlyaredescribedinanydetail,itisscarcelysurprisingthattheresultsofsocialbenefit-costanalysisoftenhaveappearedtoberegardedwithsuspicionbysomenontechnicaldecisionmakersandthepublicatlarge.ProblemsofBenefit-CostAnalysisAcaseinpointwasthepoliticalselectionofanothersiteforthethirdLondonairportinthefaceofstrongbenefit-costargumentsforalltheotherevaluatedsite.TheworkoftheRoyalCommissiononthethirdLondonairportmustrankasoneofthemostextensiveandcostlybenefitanalysesevercarriedout.Thefindingsofthecommissionwerebasedonbenefit-costanalysis,buttheywereoverturnedbytheBritishgovernmentbecauseitwasapparenttoan“intelligentlayman”thatthefindingswereobviouslywrong.Firstitmustberecognizedthatthetreatmentofexternalitiesandsomeotherquantifiableimpactsintermsofadditionalmonetarycostsandbenefitstobeaddedintothedirectcashflowislikelytobeaprocessofgreatuncertaintywhichmayleadtodisagreementwithotherplannersandconfusionfordecisionmakers.Similarlythereissharpdisagreementonthetruevalueoftraveltimesavingsandmuchdebateaboutthequestionofwhetherverysmallsavingshaveanyvalueatall.ProblemsofBenefit-CostAnalysisOftencallednotionalvalues,indirectcostsandbenefitsofthisnatureaccountforalargeproportionofthetotalcostsandbenefitsthatareinvolvedinthemostsophisticatedextendedsocialbenefitcostanalyses.Evenmoredebatableisthequestionofthestabilityofthesenotionalvaluesovertheverylongperiodsoftimeinvolvedinstrategicplans.Anumberofwritersindicatethatevenbasicsocialvaluesmaychangeasdevelopednationsenterthepostindustrialphase.Thequestionofthediscountrateitselfposedseverephilosophicalquestionswhenexaminedinthecontextoflong-termplanning.Inmanycountries,ithasbeenrequiredforyearsthatpublicinvestmentshouldbringratesofreturnthatreflecttheopportunitycostofcapitalinvestedintheprivatesector.Undercurrentconditions,theuseofhighdiscountratesmightthereforeappearrationalinlong-termplanning.Someanalystshavethereforearguedthatthistypeofanalysis,whichheavilydiscountsfuturestatesandgivespreferencetotheshortterm,ismostunsuitableforlong-termplanning.ProblemsofBenefit-CostAnalysisFurtherfundamentaldifficultiesarisefromtherecognizedfactthatsocietyispluralistic.Whileasingle-benefit-costratiocanindicatethatasawholesocietywillgainanetbenefitfromacertaincourseofaction,thesingle-benefit-costratiocannotindicatewhoisgainingthebenefitsandwhoispayingthecost.Itisentirelypossiblethatinthecaseofthelocationofanairportorthechoiceofthealignmentofafreewaythecostsincurredtotheaffectedpartsofthecommunitymaybemuchlargerthantheconcomitantbenefitstothem.Thesethreebasicproblemsallpointoutthatwhilebenefit-costanalysismaybeverysuitableforcomparingtwosimilarschemes,itislesssuitableforprovidingacomprehensiveevaluationofthemultiplicityoffactorsthatareimpliedbyalong-termtransportationplan.Plannerstoofrequentlymakethemistakeofstrivingformathematicalratherthanphilosophicalrigor.ExercisesTrueorfalse.Wherebenefit-costratiosinexcessofunityareobtained,theprojectisconsideredworthwhileandbeneficial.Theresultsofsocialbenefit-costanalysiswerenotsuspectedbysomenontechnicaldecisionmakersandthepublic.Manywritersthinkthatthebasicsocialvaluescannotchangeasdevelopednationsenterthepostindustrialphase.Undercurrentconditions,theuseofhighdiscountratesmightthereforeappearrationalinlong-termplanning.Planner