数据库系统的核心组成部分是()。

A、DB
B、DB
C、DBA
D、DBMS
查看答案
正确答案:

D

答案解析:

暂无解析

上一题
你可能感兴趣的试题

翻译:

Bymakingvehicleslighterinweightaluminumhasgreatlyreducedtheamountoffuelneededtomovethem,(PassageTwo)

Inthelast12yearstotalemploymentintheUnitedStatesgrewfasterthanatanytimeinthepeacetimehistoryofanycountry–from82to110millionbetween1973and1985–thatis,byafullonethird.Theentiregrowth,however,wasinmanufacturing,andespeciallyinno–blue-collarjobs…

Thistrendisthesameinalldevelopedcountries,andis,indeed,evenmorepronouncedinJapan.Itisthereforehighlyprobablethatin25yearsdevelopedcountriessuchastheUnitedStatesandJapanwillemploynolargeraproportionofthelaborforceInmanufacturingthandevelopedcountriesnowemployinfarming–atmost,10percent.TodaytheUnitedStatesemploysaround18millionpeopleinblue-collarjobsinmanufacturingindustries.By2010,thenumberislikelytobenomorethan12million.Insomemajorindustriesthedropwillbeevensharper.Itisquiteunrealistic,forinstance,toexpectthattheAmericanautomobileindustrywillemploymorethanone–thirdofitspresentblue-collarforce25yearshence,eventhoughproductionmightbe50percenthigher.

Ifacompany,anindustryoracountrydoesnotinthenextquartercenturysharplyincreasemanufacturingproductionandatthesametimesharplyreducetheblue-collarworkforce,itcannothopetoremaincompetitive–oreventoremain“developed.”Theattempttopreservesuchblue–collarjobsisactuallyaprescriptionforunemployment…

ThisisnotaconclusionthatAmericanpoliticians,laborleadersorindeedthegeneralpubliccaneasilyunderstandoraccept.WhatconfusestheissueevenmoreitthattheUnitedStatesisexperiencingseveralseparateanddifferentshiftsinthemanufacturingeconomy.Oneistheaccelerationofthesubstitutionofknowledgeandcapitalformanuallabor.Wherewespokeofmechanizationafewdecadesago,wenowspeakof“robotization“or“automation.”Thisisactuallymoreachangeinterminologythanachangeinreality.WhenHenryFordintroducedtheassemblylinein1909,hecutthenumberofman–hoursrequiredtoproduceamotorcarbysome80percentintwoorthreeyears–farmorethananyoneexpectstoresultfromeventhemostcompleterobotization.Butthereisnodoubtthatwearefacinganew,sharpaccelerationinthereplacementofmanualworkersbymachines–thatis,bytheproductsofknowledge.

1.Accordingtotheauthor,theshrinkageinthemanufacturinglaborforcedemonstrates______.

A.thedegreetowhichacountry’sproductionisrobotized

B.areductioninacountry’smanufacturingindustries

C.aworseningrelationshipbetweenlaborandmanagement

D.thedifferencebetweenadevelopedcountryandadevelopingcountry

2.Accordingtotheauthor,incoming25years,adevelopedcountryorindustry,inordertremaincompetitive,oughtto______.

A.reducethepercentageoftheblue-collarworkforce

B.preserveblue–collarjobsforinternationalcompetition

C.acceleratemotor–canmanufacturinginHenryFord’sstyle

D.solvetheproblemofunemployment

3.Americanpoliticiansandlaborleaderstendtodislike_____.

A.confusioninmanufacturingeconomy

B.anincreaseinblue–collarworkforce

C.internalcompetitioninmanufacturingproduction

D.adropintheblue–collarjobopportunities

4.Theword“prescription”in“aprescriptionforunemployment”maybetheequivalentto______

A.somethingrecommendedasmedicaltreatment

B.awaysuggestedtoovercomesomedifficulty

C.somemeasurestakeninadvance

D.adevicetodire

5.Thispassagemayhavebeenexceptedfrom________

A.amagazineaboutcapitalinvestment

B.anarticleonautomation

C.amotor-carmagazine

D.anarticleonglobaleconomy

Yesterdaywassucha____daywedecidedtogoforadrive.

A、glorious
B、dynamical
C、avenue
D、invitation

Iftheoldmaximthatthecustomerisalwaysrightstillhasmeaning,thentheairlinesthatplytheworld’sbusiestairroutebetweenLondonandParishaveaflightontheirhands.

TheEurostartrainservicelinkingtheUKandFrenchcapitalsviatheChannelTunneliswinningcustomersinincreasingnumbers.InlateMay,itcarrieditsonemillionthpassenger,havingrunonlyalimitedservicebetweenLondon,ParisandBrusselssinceNovember1994,startingwithtwotrainsadayineachdirectiontoParisandBrussels.By1997,thecompanybelievesthatitwillbecarryingtenmillionpassengersayear,andcontinuetogrowfromthere.

FromJuly,EurostarstepsitsservicetoninetrainseachwaybetweenLondonandParis,andfivebetweenLondonandBrussels.Eachtraincarriesalmost800passengers,210oftheminfirstclass.

Theairlinesestimatethattheywillinitiallylosearound15%-20%oftheirLondon-ParistraffictotherailwaysonceEurostarstartsafullservicelaterthisyear(1995),with15trainsadayeachway.AsimilarservicewillstarttoBrussels.Thedamagewillbelimited,however,theairlinesbelieve,withpassengernumbersreturningtopreviouslevelswithintwotothreeyears.

Intheshortterm,thedamagecausedbythe1millionpeople-levelstravelingbetweenLondonandParisandBrusselsonEurostartrainsmeansthatsomeairservicesarealreadysuffering.Someofthemajorcarrierssaythattheirpassengernumbersaredownbylessthan5%andpointtotheirrivals-ParticularlyAirFrance-ashavingsufferedtheproblems.OntheBrusselsroute,therailwaycompanyhadlesssuccess,andtheairlinesreportanythingfromarounda5%droptonovisibledeclineintraffic.

Theairlines’optimismonreturningtrafficlevelsisbasedonhistoricalprecedent.BritishMidland,forexample,pointstoitsexperienceonHeathrowLeedsBradfordservicewhichsawpassengernumbersfoldby15%whenBritishRailelectrifiedandmodernizedtherailwaylinebetweenLondonandYorkshire.Twoyearslater,travelhadrisenbetweenthetwodestinationstothepointwheretheairlinewascarryingrecordnumbersofpassengers.

1.Britishairlinesconfideinthefactthat__.

A.theyaremorepowerfulthanotherEuropeanairlines.

B.theirtotallosswon’tgobeyondadropof5%passengers.

C.theirtrafficlevelswillreturnin2-3years.

D.travelingbyrailcannevercatchupwithtravelingbyair.

2.Theauthor’sattitudetowardsthedropofpassengersmaybedescribedas__.

A.worried.B.delightedC.puzzled.D.unrivaled.

3.Inthepassage,BritishRail(Para6)ismentionedto__.

A.provideacomparisonwithEurostar.

B.supporttheairlines’optimism.

C.provetheinevitabledropofairpassengers.

D.callforelectrificationandmodernizationoftherailway.

4.Therailway’sBrusselsrouteisbroughtforthtoshowthat__.

A.theEurostartrainserviceisnotdoinggoodbusiness.

B.theairlinescanwellcompetewiththerailway.

C.theEurostartrainserviceonlycausedlittledamage.

D.onlysomeairlines,suchasAirFrance,aresuffering.

5.Thepassageistakenfromthefirstofanessay,fromwhichwemaywellpredictthatinthefollowingparttheauthorisgoingto__.

A.praisetheairlines’clear-mindedness.

B.warntheairlinesofhigh-speedrailservices.

C.proposeareductionofLondon/Parisflights.

D.advisetheairlinestofollowBritishMidlandastheirmodel.

某孕妇胎膜早破,评估胎儿状况时,下列临床表现不属于胎儿窘迫的是

A、胎心率﹤100次/分
B、破膜后羊水黄染
C、多次出现晚期减速
D、胎儿头皮血pH値725
热门试题 更多>
相关题库更多>
信息系统开发与管理
网络工程
网络操作系统
通信概论
数据库系统原理
数据结构
软件开发工具
计算机网络原理
计算机网络安全
互联网及其应用
工程经济
Java语言程序设计一
试卷库
试题库