【单选题】 EnDEmiC DisEAsEs ArE DisEAsEs thAt hABituAl inFECt only thosE pErsons living within CErtAin gEogrAphiCAl limits.
【单选题】thE moBilE rivEr AnD its triButAriEs, whiCh Flow south to thE gulF oF mExiCo, Form most importAnt rivEr systEm in AlABAmA.
【单选题】gEothErmAlEnErgy
gEothErmAl EnErgy is nAturAl hEAt From thE intErior oF thEEArth thAt is ConvErtED to hEAt BuilDings AnD gEnErAtE ElECtriCity. thE iDEA oF hArnEssingEArth’s intErnAl hEAt is not nEw.As EArly As 1904, gEothErmAl powEr wAs usED in itAly. toDAy,EArth’s nAturAl intErnAl hEAt is BEing usED to gEnErAtE ElECtriCity in 21 CountriEs, inCluDing russiA, jApAn, nEw zEAlAnD, iCElAnD, mExiCo,EthiopiA, guAtEmAlA,E1 sAlvADor, thE philippinEs, AnD thE unitED stAtEs. totAl worlDwiDE proDuCtion is ApproAChing 9,000 mw (EquivAlEnt to ninE lArgE moDErn CoAl-Burning or nuClEAr powEr plAnts)--DouBlE thE Amount in 1980. somE 40 million pEoplE toDAy rECEivE thEir ElECtriCity From gEothErmAl EnErgy At A Cost CompEtitivE with thAt oF othEr EnErgy sourCEs. inE1 sAlvADor, gEothErmAl EnErgy is supplying 30% oF thE totAl ElECtriC EnErgy usED、howEvEr, At thE gloBAl lEvEl, gEothErmAl EnErgy suppliEs lEss thAn 0.15% oF thE totAl EnErgy supply.
gEothErmAl EnErgy mAy BE ConsiDErED A nonrEnEwABlE EnErgy sourCE whEn rAtEs oF ExtrACtion ArE grEAtEr thAn rAtEs oF nAturAl rEplEnishmEnt. howEvEr, gEothErrnAl EnErgy hAs its origin in thE nAturAl hEAt proDuCtion withinEArth, AnD only A smAll FrACtion oF thE vAst totAl rEsourCE BAsE is BEing utilizED toDAy. Although most gEothErmAl EnErgy proDuCtion involvEs thE tApping oF high hEAt sourCEs, pEoplE ArE Also using thE low-tEmpErAturE gEothErmAl EnErgy oF grounDwAtEr in somE AppliCAtions.
gEothErmAl systEms
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thE AvErAgE hEAt Flow From thE intErior oF thEEArth is vEry low, ABout 0.06 w/m2.
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this Amount is triviAl CompArED with thE 177 w/m2 From solAr hEAt At thE surFACE in thE unitED stAtEs. howEvEr, in somE ArEAs, hEAt Flow is suFFiCiEntly high to BE usEFul For proDuCing EnErgy. For thE most pArt, ArEAs oF high hEAt Flow ArE AssoCiAtED with plAtE tECtoniC BounDAriEs. oCEAniC riDgE systEms (DivErgEnt plAtE BounDAriEs) AnD ArEAs whErE mountAins ArE BEing upliFtED AnD volCAniC islAnD ArCs ArE Forming (ConvErgEnt plAtE BounDAriEs ArE ArEAs whErE this nAturAl hEAt Flow is AnomAlously high.
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on thE BAsis oF gEologiCAl CritEriA, sEvErAl typEs oF hot gEothErmAl systEms (with tEmpErAturEs grEAtEr thAn ABout 80℃, or 176℉) hAvE BEEn DEFinED, AnD thE rEsourCE BAsE is lArgEr thAn thAt oF Fossil FuEls AnD nuClEAr EnErgy ComBinED、A、Common systEm For EnErgy DEvElopmEnt is hyDrothErmAl ConvECtion, ChArACtErizED By thE CirCulAtion oF stEAm AnD/or hot wAtEr thAt trAnsFErs hEAt From DEpths to thE surFACE.
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gEothErmAlEnErgy AnD thEEnvironmEnt
thE EnvironmEntAl impACt oF gEothErmAl EnErgy mAy not BE As ExtEnsivE As thAt oF othEr sourCEs oF EnErgy, But it CAn BE ConsiDErABlE. whEn gEothErmAl EnErgy is DEvElopED At A pArtiCulAr sitE, EnvironmEntAl proBlEms inCluDE on-sitE noisE, Emissions oF gAs, AnD DisturBAnCE oF thE lAnD At Drilling sitEs, DisposAl sitEs, roADs AnD pipElinEs, AnD powEr plAnts.DEvElopmEnt oF gEothErmAl EnErgy DoEs not rEquirE lArgE-sCAlE trAnsportAtion oF rAw mAtEriAls or rEFining oF ChEmiCAls, As DEvElopmEnt oF Fossil FuEls DoEs. FurthErmorE, gEothErmAl EnErgy DoEs not proDuCE thE AtmosphEriC pollutAnts AssoCiAtED with Burning Fossil FuEls or thE rADioACtivE wAstE AssoCiAtED with nuClEAr EnErgy. howEvEr, gEothErmAl DEvElopmEnt oFtEn DoEs proDuCE ConsiDErABlE thErmAl pollution From hot wAstE-wAtEr, whiCh mAy BE sAlinE or highly CorrosivE, proDuCing DisposAl AnD trEAtmEnt proBlEms.
gEothErmAl powEr is not vEry populAr in somE loCAtions Among somE pEoplE. For instAnCE, gEothErmAl EnErgy hAs BEEn proDuCED For yEArs on thE islAnD oF hAwAii, whErE ACtivE volCAniC
gEothErmAl EnErgy is nAturAl hEAt From thE intErior oF thEEArth thAt is ConvErtED to hEAt BuilDings AnD gEnErAtE ElECtriCity. thE iDEA oF hArnEssingEArth’s intErnAl hEAt is not nEw.As EArly As 1904, gEothErmAl powEr wAs usED in itAly. toDAy,EArth’s nAturAl intErnAl hEAt is BEing usED to gEnErAtE ElECtriCity in 21 CountriEs, inCluDing russiA, jApAn, nEw zEAlAnD, iCElAnD, mExiCo,EthiopiA, guAtEmAlA,E1 sAlvADor, thE philippinEs, AnD thE unitED stAtEs. totAl worlDwiDE proDuCtion is ApproAChing 9,000 mw (EquivAlEnt to ninE lArgE moDErn CoAl-Burning or nuClEAr powEr plAnts)--DouBlE thE Amount in 1980. somE 40 million pEoplE toDAy rECEivE thEir ElECtriCity From gEothErmAl EnErgy At A Cost CompEtitivE with thAt oF othEr EnErgy sourCEs. inE1 sAlvADor, gEothErmAl EnErgy is supplying 30% oF thE totAl ElECtriC EnErgy usED、howEvEr, At thE gloBAl lEvEl, gEothErmAl EnErgy suppliEs lEss thAn 0.15% oF thE totAl EnErgy supply.
gEothErmAl EnErgy mAy BE ConsiDErED A nonrEnEwABlE EnErgy sourCE whEn rAtEs oF ExtrACtion ArE grEAtEr thAn rAtEs oF nAturAl rEplEnishmEnt. howEvEr, gEothErrnAl EnErgy hAs its origin in thE nAturAl hEAt proDuCtion withinEArth, AnD only A smAll FrACtion oF thE vAst totAl rEsourCE BAsE is BEing utilizED toDAy. Although most gEothErmAl EnErgy proDuCtion involvEs thE tApping oF high hEAt sourCEs, pEoplE ArE Also using thE low-tEmpErAturE gEothErmAl EnErgy oF grounDwAtEr in somE AppliCAtions.
gEothErmAl systEms
on thE BAsis oF gEologiCAl CritEriA, sEvErAl typEs oF hot gEothErmAl systEms (with tEmpErAturEs grEAtEr thAn ABout 80℃, or 176℉) hAvE BEEn DEFinED, AnD thE rEsourCE BAsE is lArgEr thAn thAt oF Fossil FuEls AnD nuClEAr EnErgy ComBinED、A、Common systEm For EnErgy DEvElopmEnt is hyDrothErmAl ConvECtion, ChArACtErizED By thE CirCulAtion oF stEAm AnD/or hot wAtEr thAt trAnsFErs hEAt From DEpths to thE surFACE.
gEothErmAlEnErgy AnD thEEnvironmEnt
thE EnvironmEntAl impACt oF gEothErmAl EnErgy mAy not BE As ExtEnsivE As thAt oF othEr sourCEs oF EnErgy, But it CAn BE ConsiDErABlE. whEn gEothErmAl EnErgy is DEvElopED At A pArtiCulAr sitE, EnvironmEntAl proBlEms inCluDE on-sitE noisE, Emissions oF gAs, AnD DisturBAnCE oF thE lAnD At Drilling sitEs, DisposAl sitEs, roADs AnD pipElinEs, AnD powEr plAnts.DEvElopmEnt oF gEothErmAl EnErgy DoEs not rEquirE lArgE-sCAlE trAnsportAtion oF rAw mAtEriAls or rEFining oF ChEmiCAls, As DEvElopmEnt oF Fossil FuEls DoEs. FurthErmorE, gEothErmAl EnErgy DoEs not proDuCE thE AtmosphEriC pollutAnts AssoCiAtED with Burning Fossil FuEls or thE rADioACtivE wAstE AssoCiAtED with nuClEAr EnErgy. howEvEr, gEothErmAl DEvElopmEnt oFtEn DoEs proDuCE ConsiDErABlE thErmAl pollution From hot wAstE-wAtEr, whiCh mAy BE sAlinE or highly CorrosivE, proDuCing DisposAl AnD trEAtmEnt proBlEms.
gEothErmAl powEr is not vEry populAr in somE loCAtions Among somE pEoplE. For instAnCE, gEothErmAl EnErgy hAs BEEn proDuCED For yEArs on thE islAnD oF hAwAii, whErE ACtivE volCAniC
【单选题】gADgEts with A sportingChAnCE
ConsumEr ElECtroniCs: nEw sports EquipmEnt, From tEnnis rACkEts to running shoEs, usEs proCEssing powEr to EnhAnCE pErFormAnCE. is thAt FAir why shoulD Aspiring AthlEtEs stAnD on thE siDElinEs whEn A spot oF ElECtroniC AssistAnCE CAn put thEm in thE miDDlE oF thE gAmE thAt is thE quEstion mAny sports-EquipmEnt mAkErs ArE Asking As thEy sEnsE An opportunity to Boost thEir sAlEs with high-tECh proDuCts. you CoulD CAll it thE rEvEngE oF thE nErDs: A nEw wAvE oF miCroChip-EquippED sporting gooDs promisEs to EnhAnCE thE pErFormAnCE oF noviCEs AnD non-sporting typEs AlikE--AnD CoulD EvEn mAkE DiFFiCult sports EAsiEr.
tAkE Cross-Country skiing. viCtor pEtrEnko, An EnginEEr AtDArtmouthCollEgE’s iCE rEsEArCh lAB in nEw hAmpshirE, hAs invEntED somE smArt ski-BrAkEs thAt, hE BEliEvEs, will inCrEAsE thE populArity oF Cross-Country skiing By mAking thE sport lEss ChAllEnging For BEginnErs. thE BrAkEs, CurrEntly BEing tEstED By A ski mAnuFACturEr in thEAlps, oFFEr thE nECEssAry FriCtion For A BiggEr "kiCk-oFF ForCE" AnD mAkE thE skis lEss likEly to sliDE BACkwArDs in thEir trACks. to mAkE this hAppEn, An ElECtriC CurrEnt From thE Bottom oF thE skis pulsEs through thE iCE, mElting A thin lAyEr oF snow thAt instAntly rEFrEEzEs AnD ACts As A sort oF gluE.
this is not thE only Form oF smArt ski to hit thE slopEs.AtomiC, A lEADing ski-mAkEr BAsED inAustriA, plAns to introDuCE A systEm lAtEr this yEAr thAt runs A DiAgnostiC sAFEty ChECk to EnsurE thAt thE ski BinDing is propErly ClosED, with thE rEsult BEing shown on A tiny Built-in liquiD-CrystAl DisplAy. mEAnwhilE, tEnnis EquipmEnt mAnuFACturErs ArE hoping thAt innovAtion will Bring nEw zip to thEir BusinEss As wEll. thEy CErtAinly nEED to Do somEthing: ACCorDing to sportsCAnlnFo, A mArkEt-rEsEArCh Firm BAsED in FloriDA, sAlEs oF tEnnis rACkEts inAmEriCA FEll 12.5% During thE First hAlF oF 2004 CompArED with thE First hAlF oF 2003.
with thE BAll ClEArly in thEir Court, rEsEArChErs At hEAD, A mAkEr oF sporting EquipmEnt, hAvE DEvisED A proDuCt thAt shoulD AppEAl to plAyErs suFFEring From tEnnis ElBow.A、Chip insiDE thE rACkEt Controls piEzo-ElECtriC FiBrEs, whiCh ConvErt mEChAniCAl EnErgy From thE BAll’s impACt into ElECtriCAl potEntiAl EnErgy. this EnErgy is thEn usED to gEnErAtE A CountEr-ForCE in thE piEzo-ElECtriC FiBrEs thAt CAusEs A DAmpEning EFFECt.All oF this, thE Firm sAys, trAnslAtEs into lEss strEss on thE ElBow. hEAD ClAims thAt rEsiDuAl viBrAtions in thE rACkEt ArE DAmpEnED twiCE As FAst As in ConvEntionAl rACkEts, rEDuCing thE shoCk ExpEriEnCED By thE plAyEr’s Arm By morE thAn 50%.
no DouBt purists will oBjECt thAt this is simply not CriCkEt. rulE-mAkErs in mAny sports ArE now BEing ForCED to ConsiDEr thE impliCAtions oF EquipmEnt thAt promisEs to AugmEnt AthlEtEs’ pErFormAnCE with ElECtroniC musClE. thE intErnAtionAl tEnnis FEDErAtion, thAt BoDy is rEsponsiBlE For sEtting thE rulEs oF thE gAmE, hAs spECiFiED in its most rECEnt guiDElinEs thAt "no EnErgy sourCE thAt in Any wAy ChAngEs or AFFECts thE plAying ChArACtEristiCs oF A rACkEt mAy BE Built into or AttAChED to A rACkEt".
yEt DEspitE suCh worDing, thE guiDElinE DoEs not ACtuAlly EliminAtE thE usE oF hEAD’s smArt rACkEts, BECAusE thErE is no ExtErnAl EnErgy sourCE--thE DAmping EFFECt rEliEs solEly on EnErgy From thE BAll’s impACt. though high-tECh EquipmEnt mAy CAusE ControvErsy on thE Court, tEnnis CluBs hAvE to ADhErE to thE guiDElinEs sEt For thE sport, ExplAins stuArt millEr, thE itF’s tEChniCAl mAnAgEr.AnD iF thE rulEs Allow sElF-gEnErAtED ForCEs to moDiFy A rACkEt’s rEsponsE, so BE it.
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DiFFErEnt sports hAvE EnCountErED DiFFErEnt tEChnologiEs, though thE FuturE will unDouBtEDly Bring morE ovErlAp.
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in golF, gADgEts thAt pinpoint thE loCAtion oF thE g
ConsumEr ElECtroniCs: nEw sports EquipmEnt, From tEnnis rACkEts to running shoEs, usEs proCEssing powEr to EnhAnCE pErFormAnCE. is thAt FAir why shoulD Aspiring AthlEtEs stAnD on thE siDElinEs whEn A spot oF ElECtroniC AssistAnCE CAn put thEm in thE miDDlE oF thE gAmE thAt is thE quEstion mAny sports-EquipmEnt mAkErs ArE Asking As thEy sEnsE An opportunity to Boost thEir sAlEs with high-tECh proDuCts. you CoulD CAll it thE rEvEngE oF thE nErDs: A nEw wAvE oF miCroChip-EquippED sporting gooDs promisEs to EnhAnCE thE pErFormAnCE oF noviCEs AnD non-sporting typEs AlikE--AnD CoulD EvEn mAkE DiFFiCult sports EAsiEr.
tAkE Cross-Country skiing. viCtor pEtrEnko, An EnginEEr AtDArtmouthCollEgE’s iCE rEsEArCh lAB in nEw hAmpshirE, hAs invEntED somE smArt ski-BrAkEs thAt, hE BEliEvEs, will inCrEAsE thE populArity oF Cross-Country skiing By mAking thE sport lEss ChAllEnging For BEginnErs. thE BrAkEs, CurrEntly BEing tEstED By A ski mAnuFACturEr in thEAlps, oFFEr thE nECEssAry FriCtion For A BiggEr "kiCk-oFF ForCE" AnD mAkE thE skis lEss likEly to sliDE BACkwArDs in thEir trACks. to mAkE this hAppEn, An ElECtriC CurrEnt From thE Bottom oF thE skis pulsEs through thE iCE, mElting A thin lAyEr oF snow thAt instAntly rEFrEEzEs AnD ACts As A sort oF gluE.
this is not thE only Form oF smArt ski to hit thE slopEs.AtomiC, A lEADing ski-mAkEr BAsED inAustriA, plAns to introDuCE A systEm lAtEr this yEAr thAt runs A DiAgnostiC sAFEty ChECk to EnsurE thAt thE ski BinDing is propErly ClosED, with thE rEsult BEing shown on A tiny Built-in liquiD-CrystAl DisplAy. mEAnwhilE, tEnnis EquipmEnt mAnuFACturErs ArE hoping thAt innovAtion will Bring nEw zip to thEir BusinEss As wEll. thEy CErtAinly nEED to Do somEthing: ACCorDing to sportsCAnlnFo, A mArkEt-rEsEArCh Firm BAsED in FloriDA, sAlEs oF tEnnis rACkEts inAmEriCA FEll 12.5% During thE First hAlF oF 2004 CompArED with thE First hAlF oF 2003.
with thE BAll ClEArly in thEir Court, rEsEArChErs At hEAD, A mAkEr oF sporting EquipmEnt, hAvE DEvisED A proDuCt thAt shoulD AppEAl to plAyErs suFFEring From tEnnis ElBow.A、Chip insiDE thE rACkEt Controls piEzo-ElECtriC FiBrEs, whiCh ConvErt mEChAniCAl EnErgy From thE BAll’s impACt into ElECtriCAl potEntiAl EnErgy. this EnErgy is thEn usED to gEnErAtE A CountEr-ForCE in thE piEzo-ElECtriC FiBrEs thAt CAusEs A DAmpEning EFFECt.All oF this, thE Firm sAys, trAnslAtEs into lEss strEss on thE ElBow. hEAD ClAims thAt rEsiDuAl viBrAtions in thE rACkEt ArE DAmpEnED twiCE As FAst As in ConvEntionAl rACkEts, rEDuCing thE shoCk ExpEriEnCED By thE plAyEr’s Arm By morE thAn 50%.
no DouBt purists will oBjECt thAt this is simply not CriCkEt. rulE-mAkErs in mAny sports ArE now BEing ForCED to ConsiDEr thE impliCAtions oF EquipmEnt thAt promisEs to AugmEnt AthlEtEs’ pErFormAnCE with ElECtroniC musClE. thE intErnAtionAl tEnnis FEDErAtion, thAt BoDy is rEsponsiBlE For sEtting thE rulEs oF thE gAmE, hAs spECiFiED in its most rECEnt guiDElinEs thAt "no EnErgy sourCE thAt in Any wAy ChAngEs or AFFECts thE plAying ChArACtEristiCs oF A rACkEt mAy BE Built into or AttAChED to A rACkEt".
yEt DEspitE suCh worDing, thE guiDElinE DoEs not ACtuAlly EliminAtE thE usE oF hEAD’s smArt rACkEts, BECAusE thErE is no ExtErnAl EnErgy sourCE--thE DAmping EFFECt rEliEs solEly on EnErgy From thE BAll’s impACt. though high-tECh EquipmEnt mAy CAusE ControvErsy on thE Court, tEnnis CluBs hAvE to ADhErE to thE guiDElinEs sEt For thE sport, ExplAins stuArt millEr, thE itF’s tEChniCAl mAnAgEr.AnD iF thE rulEs Allow sElF-gEnErAtED ForCEs to moDiFy A rACkEt’s rEsponsE, so BE it.
【单选题】 Electoral politics in the United States has been dominated by two political parties since the administer of George Washington.
【单选题】 The word "biting" in line 8 is closest in meaning to
A．( simple
B．( sorrowful
C．( frequent
D．( sharp
A．( simple
B．( sorrowful
C．( frequent
D．( sharp
【单选题】 Which of the following is mentioned as the dominant theme in Roesen's painting
A．( Fertility
B．( Freedom
C．( Impermanence
D．( Abundance
A．( Fertility
B．( Freedom
C．( Impermanence
D．( Abundance
【单选题】 One of the (most impressive) cultural achievements of the United State (during) the 1920's was a (vastly) outpouring of (serious literature).
A．most impressive
B．during
C．vastly
D．serious literature
A．most impressive
B．during
C．vastly
D．serious literature
【单选题】nEw-AgE trAnsport
it looks As iF it CAmE strAight From thE sEt oF stAr wArs. it hAs Four-whEEl DrivE AnD risEs ABovE roCky surFACEs. it lowErs AnD rAisEs its nosE whEn going up AnD Down hills.AnD whEn it ComEs to A rivEr, it turns AmphiBious: two hyDrojEt powEr it Along By BlAsting wAtEr unDEr its BoDy. thErE is room For two pAssEngErs AnD A DrivEr, who sit insiDE A glAss BuBBlE opErAting ElECtroniC, AirCrAFt-typE Controls.A、vEhiClE so DAring on lAnD AnD wAtEr nEEDs winDsCrEEn wipErs--But it DoEsn’t hAvE Any. wAtEr molECulEs ArE DisintEgrAtED on thE sCrEEn’s surFACE By ultrAsoniC sEnsors.
this unusuAl vEhiClE is thE rACoon. it is An invEntion not oF hollywooD But oF rEnAult, A rAthEr ConsErvAtivE FrEnCh stAtE-ownED CAr-mAkEr, BEttEr known For its FAmily hAtChBACks. rEnAult Built thE rACoon to ExplorE nEw FrEEDoms For DEsignErs AnD EnginEErs CrEAtED By ADvAnCEs in mAtEriAls AnD mAnuFACturing proCEssEs. rEnAult is thinking ABout stArtlingly DiFFErEnt CArs; othEr proDuCErs hAvE rADiCAl nEw iDEAs For trAins, BoAts AnD AEroplAnEs.
thE First oF thE nEw FrEEDoms is in DEsign. powErFul ComputEr-AiDED DEsignCAD、systEms CAn rEplACE with A CliCk oF A ComputEr mousE hours oF lABorious work DonE on thousAnDs oF DrAwing BoArDs. so nEw proDuCts, no mAttEr how CompliCAtED, CAn BE DEvElopED muCh FAstEr. For thE First timE,BoEing will not hAvE to BuilD A giAnt rEpliCA oF its nEw AirlinEr, thE 777, to mAkE surE All thE Bits Fit togEthEr. itsCA
D、systEm will tAkE CArE oF thAt.
But rEnAult is tAkingCA
D、FurthEr. it ClAims thE rACoon is thE worlD’s First vEhiClE to BE DEsignED within thE DigitisED worlD oF virtuAl rEAlity.ComplEx progrAms wErE usED to simulAtE thE vEhiClE AnD thE tErrAin thAt it wAs ExpECtED to Cross. this AllowED A tEAm lED By pAtriCk g. m. lE quémEnt , rEnAult’s inDustriAl-DEsign DirECtor, to "DrivE" it long BEForE A prototypE ExistE
D、
rEnAult is not AlonE in thinking thAt virtuAl rEAlity will trAnsForm AutomotivE DEsign. inDEtroit, ForD is Also invEstigAting its potEntiAl. jACk turnEr, thE Firm’s hEAD oF DEsign, woulD likE DEsignErs in DiFFErEnt pArts oF thE worlD to work morE ClosEly togEthEr, linkED By ComputErs. thEy woulD Do morE thAn stylE CArs. virtuAl rEAlity will Allow EnginEErs to pEEr insiDE thE working pArt oF A vEhiClE.DEsignErs will wAtCh BEAtings movE, oil Flow, gEArs mEsh AnD hyDrAuliCs pump.As thEsE tEChniquEs CAtCh on, EvEn strAngEr vEhiClEs ArE likEly to ComE Along.
trAnsForming thEsE CrEAtions From virtuAl rEAlity to ACtuAl rEAlity will Also BEComE EAsiEr, EspECiAlly with ADvAnCEs in mAtEriAls. Firms thAt onCE BAshED EvErything out oF stEEl now FinD thAt nEw Alloys or CompositE mAtEriAls (whiCh CAn BE mADE From mixturEs oF plAstiC, rEsin, CErAmiCs AnD mEtAls, rEinForCED with FiBrEs suCh As glAss or CArBon) ArE ChAnging thE rulEs oF mAnuFACturing.At thE sAmE timE, olD mAtEriAls kEEp gEtting BEttEr, As thEir proDuCErs try to sECurE thEir plACE in thE FACtory oF thE FuturE.
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this CompEtition is inCrEAsing thE pACE oF DEvElopmEnt oF All mAtEriAls.
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onE CompAny in this FiElD is sCAlEDCompositEs.
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it wAs stArtED in 1982 ByBurr rutAn, An AviAtor who hAs DEvisED mAny unusuAl AirCrAFt.
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it hAs Also workED on CompositE sAils For thEAmEriCA’sCup yACht rACE AnD on gEnErAl motors’ ultrAlitE, A 100-milEs pEr-gAllon ExpErimEntAl FAmily CAr Built From CArBon FiBrE.
AgAin, thE rACoon rEFlECts this rACE BEtwEEn thE olD AnD thE nEw. it usEs ConvEntionAl stEEl AnD whAt rEnAult DEsCriBEs As A nEw "high-limit ElAstiC stEEl" in its ChAssis. this stEEl is 30% lightEr thAn thE usuAl kin
D、thE rACoon Also hAs pArts mADE From C
it looks As iF it CAmE strAight From thE sEt oF stAr wArs. it hAs Four-whEEl DrivE AnD risEs ABovE roCky surFACEs. it lowErs AnD rAisEs its nosE whEn going up AnD Down hills.AnD whEn it ComEs to A rivEr, it turns AmphiBious: two hyDrojEt powEr it Along By BlAsting wAtEr unDEr its BoDy. thErE is room For two pAssEngErs AnD A DrivEr, who sit insiDE A glAss BuBBlE opErAting ElECtroniC, AirCrAFt-typE Controls.A、vEhiClE so DAring on lAnD AnD wAtEr nEEDs winDsCrEEn wipErs--But it DoEsn’t hAvE Any. wAtEr molECulEs ArE DisintEgrAtED on thE sCrEEn’s surFACE By ultrAsoniC sEnsors.
this unusuAl vEhiClE is thE rACoon. it is An invEntion not oF hollywooD But oF rEnAult, A rAthEr ConsErvAtivE FrEnCh stAtE-ownED CAr-mAkEr, BEttEr known For its FAmily hAtChBACks. rEnAult Built thE rACoon to ExplorE nEw FrEEDoms For DEsignErs AnD EnginEErs CrEAtED By ADvAnCEs in mAtEriAls AnD mAnuFACturing proCEssEs. rEnAult is thinking ABout stArtlingly DiFFErEnt CArs; othEr proDuCErs hAvE rADiCAl nEw iDEAs For trAins, BoAts AnD AEroplAnEs.
thE First oF thE nEw FrEEDoms is in DEsign. powErFul ComputEr-AiDED DEsignCAD、systEms CAn rEplACE with A CliCk oF A ComputEr mousE hours oF lABorious work DonE on thousAnDs oF DrAwing BoArDs. so nEw proDuCts, no mAttEr how CompliCAtED, CAn BE DEvElopED muCh FAstEr. For thE First timE,BoEing will not hAvE to BuilD A giAnt rEpliCA oF its nEw AirlinEr, thE 777, to mAkE surE All thE Bits Fit togEthEr. itsCA
D、systEm will tAkE CArE oF thAt.
But rEnAult is tAkingCA
D、FurthEr. it ClAims thE rACoon is thE worlD’s First vEhiClE to BE DEsignED within thE DigitisED worlD oF virtuAl rEAlity.ComplEx progrAms wErE usED to simulAtE thE vEhiClE AnD thE tErrAin thAt it wAs ExpECtED to Cross. this AllowED A tEAm lED By pAtriCk g. m. lE quémEnt , rEnAult’s inDustriAl-DEsign DirECtor, to "DrivE" it long BEForE A prototypE ExistE
D、
rEnAult is not AlonE in thinking thAt virtuAl rEAlity will trAnsForm AutomotivE DEsign. inDEtroit, ForD is Also invEstigAting its potEntiAl. jACk turnEr, thE Firm’s hEAD oF DEsign, woulD likE DEsignErs in DiFFErEnt pArts oF thE worlD to work morE ClosEly togEthEr, linkED By ComputErs. thEy woulD Do morE thAn stylE CArs. virtuAl rEAlity will Allow EnginEErs to pEEr insiDE thE working pArt oF A vEhiClE.DEsignErs will wAtCh BEAtings movE, oil Flow, gEArs mEsh AnD hyDrAuliCs pump.As thEsE tEChniquEs CAtCh on, EvEn strAngEr vEhiClEs ArE likEly to ComE Along.
trAnsForming thEsE CrEAtions From virtuAl rEAlity to ACtuAl rEAlity will Also BEComE EAsiEr, EspECiAlly with ADvAnCEs in mAtEriAls. Firms thAt onCE BAshED EvErything out oF stEEl now FinD thAt nEw Alloys or CompositE mAtEriAls (whiCh CAn BE mADE From mixturEs oF plAstiC, rEsin, CErAmiCs AnD mEtAls, rEinForCED with FiBrEs suCh As glAss or CArBon) ArE ChAnging thE rulEs oF mAnuFACturing.At thE sAmE timE, olD mAtEriAls kEEp gEtting BEttEr, As thEir proDuCErs try to sECurE thEir plACE in thE FACtory oF thE FuturE.
AgAin, thE rACoon rEFlECts this rACE BEtwEEn thE olD AnD thE nEw. it usEs ConvEntionAl stEEl AnD whAt rEnAult DEsCriBEs As A nEw "high-limit ElAstiC stEEl" in its ChAssis. this stEEl is 30% lightEr thAn thE usuAl kin
D、thE rACoon Also hAs pArts mADE From C
【单选题】 Ils aimeraient bien ____________ un collaborateur plus expérimenté.
A．chercher
B． trouver
C． lire
D． se débarrasser
A．chercher
B． trouver
C． lire
D． se débarrasser
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