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微分方程Y’+(e-x-1)Y=1的通解为______。
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微分方程y+2y’-3y=xex的通解为y=______．
微分方程y’+ytanx=cosx的通解y=______．
微分方程y’+xy2-y2=1-x的通解为______．
微分方程y’+e-x-1y=1的通解为______
求微分方程xy’=y1+lny-lnx的通解．
微分方程xdy=yxy-1dx的通解为______．
微分方程y+y=-2x的通解为______．
微分方程y-3y’+2y=xex的通解为y=______．
微分方程y+4y=cos2x的通解为y=______．
微分方程y’+6y+13y’=0的通解为______．
微分方程y’+ytanx=cosx的通解为y=______．
设有微分方程x2lnxy-xy’+y=0．Ⅰ验证y1=x是微分方程的一个解Ⅱ利用变量代换y=xu化简
微分方程y+4y=cos2x的通解为y=______.
微分方程x3yy’=1-xyy’+y2的通解为______．
求微分方程y+y=sinax的通解其中a为常数．
微分方程y″+4y=cos2x的通解为y=______.
下列说法正确的是
微分方程的通解是全部解
含有任意常数的解是微分方程的通解
y
1
，y
2
是二阶方程的两个线性无关解，则y=C
1
y
1
+C
2
y
2
为其通解
n阶方程通解中必须含有n个独立的任意常数
微分方程y+y=-2x的通解为
2012已知微分方程y′+p+xy=qx［qx≠0］有两个不同的特解y1xy2x则该微分方程的通解是
y=c（y1-y2）
y=c（y1+y2）
y=y1+c（y1+y2）
y=y1+c（y1-y2）
微分方程y+y=x+cosx的通解为______．
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TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 12
Todaysome30%ofsmallbusinessownersdon’thaveaWebpresenceatallwhilethevastmajoritywhodoarewatchingtheirsitessitstalewaitingandwantingforbusiness.WheredidthingsgowrongTherearecommonprinciplesfollowedbythosewhosedreamsofonlinesuccesshavebecomereality.41Buildyoursitearoundyourcustomer:Thinkingofyoursiteasyouronlinestorefrontbuiltarounddeliveringthehighest-qualitycustomerexperiencefromthemomentyourcustomerstepsthroughthedoor.42Justbecauseyoubuiltitdoesn’tmeanthey’llcome:Ifyouaren’tseeingalargevolumeoftargetedtraffictoyoursiteit’stimetouptheante.43Integratecustomerloyaltyprogramsandpromotions:Methodscontaindiscountsnewsorfriendlyservicereminders.Usediscountpromotionalofferstostayintouchwithpastvisitorstoyoursite.44Justifyyourmonthlyspendingthroughproductbundling:Whilepay-per-clickInternetadvertisingismuchmorecost-effectivethantraditionalmediachannelsbundlingproductstogetherwillnotonlyincreaseyoursalesrevenuebutalsoenableyoutogetmoreoutofyourper-clickadrates.45Measureyourprogress:YoursitemaybelivebuthowisitperformingArmedwiththesesimplelessonsvowtomakeyourbusinessrealizethetruepromiseoftheInternet.A.Amanufacturingcompanyselling$50itemswashavingtroublejustifyingthecostofonlinekeywordads.Bybundlingproductstocreatepackagesof$100ormoreandadvertisingtowholesalecustomerslookingtobuyinbulkthemanufacturerdroppeditssalesrepresentativeagenciesandfocusedonlargevolumebuyerssuchasWal-MartandTarget.Needlesstosaythecompanyhadnotroubleexceedingitsyearlysalesquota.B.Oneofmypastclientshadawell-designedphysicalstorefrontsolidpricesandqualityofferings.Howeverhewasn’tabletodriveenoughstoretrafficdespitetargetedadvertisingeffortsinprintpublicationsandotherofflinevenues.Wedecidedtoshiftthoseaddollarstoanonlinepay-per-clickcampaign—inwhichtheadvertiserpayswheneversomeoneclicksonitsentrypostedduringthecourseofasitesearchbasedonkeywordsrelevanttohisbusiness.Theimmediateimpactwasstaggering.Onlinerevenuesoaredtenfoldto$1millionfrom$100000withinonlyafewmonths.C.Withtoday’stechnologyyourreturncanbeeasilymeasured.IfyourelyonyourWebsiteasasalestoolyoucan’taffordnottoinvestinsiteanalytics.MakesureyourWebsolutionincludesaneasy-to-usereportingtoolthatpresentsthisinformationinaclearconciseformat.AfterallwhilemetricsareacriticalpartoftheWebequationyoudon’thavethetimetospendhoursdiggingthroughreamsofdata.D.YearsagoIworkedwithawomanwhosoldpursesonlinethroughahome-builtsitethatlackedcriticale-commercecomponents.Afterasimpleredesignincludingproductdescriptionscomprehensivenavigationandasecureuser-friendlyorderingsystemherrevenueincreasedfivefold.Andshebeganreceivingravereviewsfromcustomersimpressedwiththeeaseandconvenienceoftheonlineshoppingexperience.E.Onlinesuccessdemandsmorethansimplepresence.YourInternetinvestmentshouldpayforitselfwithnewcustomersandincreasedsales.Findatrustedpartnerwhocanhelpyounavigatetoday’sandtomorrow’stechnologyandwhounderstandsthebottom-linerealitiesofyourbusiness.F.OnevillarentalcompanyhadaWebsitethatgeneratedveryfewcallsandonlinebookings.Ihelpedthecompanysetupalastminutedealsdistributionlist.Bysubscribingsitevisitorswouldreceiveweeklye-mailsoffering11th-hourdiscountsonvillarentals.Asaresultthecompanycapturedcontactinformationforthousandsofpossiblecustomersreduceditsunusedinventorytoalmostzeroandincreasedrevenuesignificantly.
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 10
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 16
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 20
Relativitytheoryhashadaprofoundinfluenceonourpictureofmatterbyforcingustomodifyourconceptofaparticleinanessentialway.46Inclassicalphysicsthemassofanobjecthadalwaysbeenassociatedwithanindestructiblematerialsubstancewithsomestuffofwhichallthingswerethoughttobemade.Relativitytheoryshowedthatmasshasnothingtodowithanysubstancebutisaformenergy.Energyhoweverisadynamicquantityassociatedwithactivityorwithprocesses.47Thefactthatthemassofaparticleisequivalenttoacertainofenergymeansthattheparticlecannolongerbeseenasastatic_objectbuthastobeconceivedasadynamicpatternaprocessinvolvingtheenergywhichmanifestitselfastheparticle’smass.48ThisnewviewofparticleswasinitiatedbyDiracwhenheformulatedarelativisticequationdescribingthebehaviorofelectrons.Dirac’stheorywasnotonlyextremelysuccessfulinaccountingforthefinedetailsofatomicstructurebutalsorevealedafundamentalsymmetrybetweenmatterandanti-matter.Itpredictedtheexistenceofananti-matterwiththesamemassastheelectronbutwithanoppositecharge.ThispositivelychargedparticlenowcalledthepositronwasindeeddiscoveredtwoyearsafterDirachadpredictedit.Thesymmetrybetweenmatterandanti-matterimpliesthatforeveryparticlethereexistsanantiparticleswithequalmassandoppositecharge.Pairsofparticlesandantiparticlescanbecreatedifenoughenergyisavailableandcanbemadetoturnintopureenergyinthereverseprocessofdestruction.49TheseprocessesofparticlecreationanddestructionhadbeenpredictedfromDirac’stheorybeforetheywereactuallydiscoveredinnatureandsincethentheyhavebeenobservedmillionsoftimes.Thecreationofmaterialparticlesfrompureenergyiscertainlythemostspectaculareffectofrelativitytheoryanditcanonlybeunderstoodintermsoftheviewofparticlesoutlinedabove.50Beforerelativisticparticlephysicstheconstituentsofmatterhadalwaysbeenconsideredasbeingeitherelementaryunitswhichwereindestructibleandunchangeableorascompositeobjectswhichcouldbebrokenupintotheirconstituentparts.Andthebasicquestionwaswhetheronecoulddividematteragainandagainorwhetheronewouldfinallyarriveatsomesmallestindivisibleunits.
Relativitytheoryhashadaprofoundinfluenceonourpictureofmatterbyforcingustomodifyourconceptofaparticleinanessentialway.46Inclassicalphysicsthemassofanobjecthadalwaysbeenassociatedwithanindestructiblematerialsubstancewithsomestuffofwhichallthingswerethoughttobemade.Relativitytheoryshowedthatmasshasnothingtodowithanysubstancebutisaformenergy.Energyhoweverisadynamicquantityassociatedwithactivityorwithprocesses.47Thefactthatthemassofaparticleisequivalenttoacertainofenergymeansthattheparticlecannolongerbeseenasastatic_objectbuthastobeconceivedasadynamicpatternaprocessinvolvingtheenergywhichmanifestitselfastheparticle’smass.48ThisnewviewofparticleswasinitiatedbyDiracwhenheformulatedarelativisticequationdescribingthebehaviorofelectrons.Dirac’stheorywasnotonlyextremelysuccessfulinaccountingforthefinedetailsofatomicstructurebutalsorevealedafundamentalsymmetrybetweenmatterandanti-matter.Itpredictedtheexistenceofananti-matterwiththesamemassastheelectronbutwithanoppositecharge.ThispositivelychargedparticlenowcalledthepositronwasindeeddiscoveredtwoyearsafterDirachadpredictedit.Thesymmetrybetweenmatterandanti-matterimpliesthatforeveryparticlethereexistsanantiparticleswithequalmassandoppositecharge.Pairsofparticlesandantiparticlescanbecreatedifenoughenergyisavailableandcanbemadetoturnintopureenergyinthereverseprocessofdestruction.49TheseprocessesofparticlecreationanddestructionhadbeenpredictedfromDirac’stheorybeforetheywereactuallydiscoveredinnatureandsincethentheyhavebeenobservedmillionsoftimes.Thecreationofmaterialparticlesfrompureenergyiscertainlythemostspectaculareffectofrelativitytheoryanditcanonlybeunderstoodintermsoftheviewofparticlesoutlinedabove.50Beforerelativisticparticlephysicstheconstituentsofmatterhadalwaysbeenconsideredasbeingeitherelementaryunitswhichwereindestructibleandunchangeableorascompositeobjectswhichcouldbebrokenupintotheirconstituentparts.Andthebasicquestionwaswhetheronecoulddividematteragainandagainorwhetheronewouldfinallyarriveatsomesmallestindivisibleunits.
Todaysome30%ofsmallbusinessownersdon’thaveaWebpresenceatallwhilethevastmajoritywhodoarewatchingtheirsitessitstalewaitingandwantingforbusiness.WheredidthingsgowrongTherearecommonprinciplesfollowedbythosewhosedreamsofonlinesuccesshavebecomereality.41Buildyoursitearoundyourcustomer:Thinkingofyoursiteasyouronlinestorefrontbuiltarounddeliveringthehighest-qualitycustomerexperiencefromthemomentyourcustomerstepsthroughthedoor.42Justbecauseyoubuiltitdoesn’tmeanthey’llcome:Ifyouaren’tseeingalargevolumeoftargetedtraffictoyoursiteit’stimetouptheante.43Integratecustomerloyaltyprogramsandpromotions:Methodscontaindiscountsnewsorfriendlyservicereminders.Usediscountpromotionalofferstostayintouchwithpastvisitorstoyoursite.44Justifyyourmonthlyspendingthroughproductbundling:Whilepay-per-clickInternetadvertisingismuchmorecost-effectivethantraditionalmediachannelsbundlingproductstogetherwillnotonlyincreaseyoursalesrevenuebutalsoenableyoutogetmoreoutofyourper-clickadrates.45Measureyourprogress:YoursitemaybelivebuthowisitperformingArmedwiththesesimplelessonsvowtomakeyourbusinessrealizethetruepromiseoftheInternet.A.Amanufacturingcompanyselling$50itemswashavingtroublejustifyingthecostofonlinekeywordads.Bybundlingproductstocreatepackagesof$100ormoreandadvertisingtowholesalecustomerslookingtobuyinbulkthemanufacturerdroppeditssalesrepresentativeagenciesandfocusedonlargevolumebuyerssuchasWal-MartandTarget.Needlesstosaythecompanyhadnotroubleexceedingitsyearlysalesquota.B.Oneofmypastclientshadawell-designedphysicalstorefrontsolidpricesandqualityofferings.Howeverhewasn’tabletodriveenoughstoretrafficdespitetargetedadvertisingeffortsinprintpublicationsandotherofflinevenues.Wedecidedtoshiftthoseaddollarstoanonlinepay-per-clickcampaign—inwhichtheadvertiserpayswheneversomeoneclicksonitsentrypostedduringthecourseofasitesearchbasedonkeywordsrelevanttohisbusiness.Theimmediateimpactwasstaggering.Onlinerevenuesoaredtenfoldto$1millionfrom$100000withinonlyafewmonths.C.Withtoday’stechnologyyourreturncanbeeasilymeasured.IfyourelyonyourWebsiteasasalestoolyoucan’taffordnottoinvestinsiteanalytics.MakesureyourWebsolutionincludesaneasy-to-usereportingtoolthatpresentsthisinformationinaclearconciseformat.AfterallwhilemetricsareacriticalpartoftheWebequationyoudon’thavethetimetospendhoursdiggingthroughreamsofdata.D.YearsagoIworkedwithawomanwhosoldpursesonlinethroughahome-builtsitethatlackedcriticale-commercecomponents.Afterasimpleredesignincludingproductdescriptionscomprehensivenavigationandasecureuser-friendlyorderingsystemherrevenueincreasedfivefold.Andshebeganreceivingravereviewsfromcustomersimpressedwiththeeaseandconvenienceoftheonlineshoppingexperience.E.Onlinesuccessdemandsmorethansimplepresence.YourInternetinvestmentshouldpayforitselfwithnewcustomersandincreasedsales.Findatrustedpartnerwhocanhelpyounavigatetoday’sandtomorrow’stechnologyandwhounderstandsthebottom-linerealitiesofyourbusiness.F.OnevillarentalcompanyhadaWebsitethatgeneratedveryfewcallsandonlinebookings.Ihelpedthecompanysetupalastminutedealsdistributionlist.Bysubscribingsitevisitorswouldreceiveweeklye-mailsoffering11th-hourdiscountsonvillarentals.Asaresultthecompanycapturedcontactinformationforthousandsofpossiblecustomersreduceditsunusedinventorytoalmostzeroandincreasedrevenuesignificantly.
OneofthemostpressingchallengesthattheUnitedStates—andindeedtheworld—willfaceinthenextfewdecadesishowtoalleviatethegrowingstressthathumanactivitiesareplacingontheenvironment.Theconsequencesarejusttoogreattoignore.Wildlifehabitatsarebeingdegradedordisappearingaltogetherasnewdevelopmentstakeupmoreland.PlantandanimalspeciesarebecomingextinctatagreaterratenowthanatanytimeinEarth’shistory.Asmanyas30percentoftheworld’sfishstocksareoverexploited.Andthelistgoeson.Yetthereisreasontohavehopeforthefuture.Advancesincomputingpowerandmolecularbiologyareamongthetremendousincreasesinscientificcapabilitythatarehelpingresearchersgainabetterunderstandingoftheseproblems.Recentdevelopmentsinscienceandtechnologycouldprovidethebasisforsomemajorandtimelyactionsthatwouldimproveourunderstandingofhowhumanactivitiesaffecttheenvironment.Onepriorityforresearchisimprovinghydrologicalforecasting.Ithasbeenestimatedthattheworld’swaterusecouldtripleinthenexttwodecades.AlreadywidespreadwatershortageshaveoccurredinpartsofChinaIndiaNorthAfricaandtheArabianPeninsula.TheneedforwateralsoistakingitstollonfreshwaterecosystemsintheUnitedStates.Only2percentofthenation’sstreamsareconsideredingoodconditionandcloseto40percentofnativefishspeciesareraretoextinct.Usingavarietyofnewremotesensingtoolsscientistscanlearnmoreabouthowprecipitationaffectswaterlevelshowsurfacewaterisgeneratedandtransportedandhowchangesinthelandscapeaffectwatersupplies.Topreventoutbreaksofinfectiousdiseasesinplantsanimalsandhumansmorestudyisneededonhowpathogensparasitesanddisease-carryingspecies—aswellashumansandotherspeciestheyinfect—areaffectedbychangesintheenvironment.Theoveruseofantibioticsbothinhumansandinfarmanimalshascontributedtothegrowthofantibiotic-resistantmicroorganisms.Researcherscantakeadvantageofnewtechnologiesingeneticsandcomputingtobettermonitorandpredicttheeffectsthatenvironmentalchangesmighthaveondiseaseoutbreaks.HumanshavemadealterationstoEarth’ssurface—suchastropicaldeforestationreductionofsurfaceandgroundwaterandmassivedevelopment—sodramaticthattheyapproachthelevelsoftransformationthatoccurredduringglacialperiods.Suchalterationscausechangesinlocalandregionalclimateandwilldeterminethefutureofagriculture.Recentadvancesindatacollectionandanalysisshouldbeusedtodocumentandbetterunderstandthecausesandconsequencesofchangesinlandcoveranduse.TheexpressionAndthelistgoesonPara.1isusedtosuggestthat
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 18
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 14
Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5.a Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5. Almostathirdofadultshavetroublesleepingandabout10percenthave6ofdaytimeimpairmentthatsignaltrueinsomnia.But7thecomplaintsscientistsknowsurprisinglylittleaboutwhatcauseschronicinsomniaitshealthconsequencesandhowbesttotreatitapanelofspecialists8togetherbytheNationalInstitutesofHealthconcludedWednesday.Thepanelcalled9abroadrangeofresearchintoinsomnia10thatifscientistsunderstoodits11causestheycoulddevelopbettertreatments. Mostbutnotallinsomniaisthoughtto12otherhealthproblemsfromarthritisanddepressiontocardiovasculardisease.Thequestionofteniswhethertheinsomniacamefirstorwasaresultoftheotherdiseasesandhowtroublesleepingin13complicatesthoseotherproblems.Otherdiseases14theriskofinsomniaseemstoincreasewithageandtobemore15amongwomenespeciallyaftertheir50s.Smokingcaffeineandnumerous16drugsalsoaffectsleep. TheNIHisspendingabout$200millionthisyearonsleep-relatedresearchsome17tospecificdisordersandothers18theunderlyingscientificlawsthatcontrolthenervoussystemofsleep.Theagencywas19thepane’sreviewbeforedecidingwhatadditionalworkshouldbe20atinsomnia. 4
Rewardsandpunishmentsareusedindifferentwaysbydifferentcommunitiestomaintainsocialorderandpreserveculturalvalues.Inallculturesparentsmustteachtheirchildrentoavoiddangerandtoobservethecommunity’smoralprecepts.Adultsalsoconditioneachother’sobservanceofsocialnormsusingmethodsrangingfrommildformsofcensuresuchaslookingawaywhensomeonemakesaninappropriateremarktoimprisoningorexecutingindividualsforbehaviorconsidereddeviantordangerous.ThecaningofAmericanteenagerMichaelFayinSingaporeforvandalismin1994broughtwidemediaattentiontoculturaldifferencesintheapplicationofpunishment.FacedwithincreasingviolenceathomemanyAmericansendorsedSingapore’suseofcorporalpunishmenttomaintainsocialorder.WasFay’spunishmenteffectiveWhetherhesubsequentlyavoidsvandalismisunknownbutthepunishmentdidapparentlyleadtohisavoidanceofSingapore—whichheleftpromptly.Theoperanttechniquessocietiesusetomaintainsocialcontrolvaryinpartwiththedangersandthreatsthatconfrontthem.TheGusiiofKenyawithahistoryoftribalwarfarefacethreatsnotonlyfromoutsidersbutalsofromnaturalforcesincludingwildanimals.Gusiiparentstendtorelymoreonpunishmentandfearthanonrewardsinconditioningappropriatesocialbehaviorintheirchildren.Caningfooddeprivationandwithdrawingshelterandprotectionarecommonformsofpunishment.IncontrasttheMixtecansofJuxtlahuacaMexicoareahighlycohesivecommunitywithlittleinternalconflictandsocialnormsthatencouragecooperation.TheirsocialpatternsappearadaptivefortheMixtecansaredominatedbythenearbySpanishMexicanswhocontroltheofficialgovernmentandmanyeconomicresourcesintheirregion.TheMixtecansdonotgenerallyimposefinesorjailsentencesorusephysicalpunishmenttodeteraggressionineitheradultsorchildren.Rathertheytendtorelyonsoothingpersuasion.Socialostracismisthemostfearedpunishmentandsocialtieswithinthecommunityareverystrongsoresponsesthatreinforcethesetiesareeffectiveinmaintainingsocialorder.IntheUnitedStatesfearofsocialostracismorstigmawasonceamorepowerfulforceinmaintainingcontroloverantisocialbehaviorespeciallyinsmallcommunities.Todayevenimprisonmentdoesnotappeartobeanadequatedeterrenttomanyformsofcrimeespeciallyviolentcrime.Althoughonereasonistheinconsistentapplicationofpunishmentanothermaybethefactthatimprisonmentnolongercarriestheintensestigmaitoncehadsothatprisonisnolongerasaneffectivepunishment.WhatwouldaGusiimotherfromKenyamostlikelydotopunishherchildren
Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5.a Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5. Almostathirdofadultshavetroublesleepingandabout10percenthave6ofdaytimeimpairmentthatsignaltrueinsomnia.But7thecomplaintsscientistsknowsurprisinglylittleaboutwhatcauseschronicinsomniaitshealthconsequencesandhowbesttotreatitapanelofspecialists8togetherbytheNationalInstitutesofHealthconcludedWednesday.Thepanelcalled9abroadrangeofresearchintoinsomnia10thatifscientistsunderstoodits11causestheycoulddevelopbettertreatments. Mostbutnotallinsomniaisthoughtto12otherhealthproblemsfromarthritisanddepressiontocardiovasculardisease.Thequestionofteniswhethertheinsomniacamefirstorwasaresultoftheotherdiseasesandhowtroublesleepingin13complicatesthoseotherproblems.Otherdiseases14theriskofinsomniaseemstoincreasewithageandtobemore15amongwomenespeciallyaftertheir50s.Smokingcaffeineandnumerous16drugsalsoaffectsleep. TheNIHisspendingabout$200millionthisyearonsleep-relatedresearchsome17tospecificdisordersandothers18theunderlyingscientificlawsthatcontrolthenervoussystemofsleep.Theagencywas19thepane’sreviewbeforedecidingwhatadditionalworkshouldbe20atinsomnia. 6
Cyberspacedatasuperhighwaysmultimedia—forthosewhohaveseenthefuturethelinkingofcomputerstelevisionandtelephoneswillchangeourlivesforever.Yetforallthetalkofaforthcomingtechnologicalutopialittleattentionhasbeengiventotheimplicationsofthesedevelopmentsforthepoor.AswithallnewhightechnologywhiletheWestconcernsitselfwiththehowthequestionofforwhomisputasideonceagain.Economistsareonlynowrealizingthefullextenttowhichthecommunicationsrevolutionhasaffectedtheworldeconomy.Informationtechnologyallowstheextensionoftradeacrossgeographicalandindustrialboundariesandtransnationalcorporationstakefulladvantageofit.Termsoftradeexchangeandinterestratesandmoneymovementsaremoreimportantthantheproductionofgoods.Theelectroniceconomymadepossiblebyinformationtechnologyallowsthehavestoincreasetheircontrolonglobalmarkets—withdestructiveimpactonthehave-nots.Forthemtheresultisinstability.Developingcountrieswhichrelyontheproductionofasmallrangeofgoodsforexportaremadetofeellikesmallpartsintheinternationaleconomicmachine.Asfuturesaretradedoncomputerscreensdevelopingcountriessimplyhavelessandlesscontroloftheirdestinies.SowhataretheoptionsforregainingcontrolOnealternativeisfordevelopingcountriestobuyinthelatestcomputersandtelecommunicationsthemselves—socalleddevelopmentcommunicationsmodernization.Yetthisleadstolong-termdependencyandperhapspermanentconstraintsondevelopingcountries’economies.CommunicationstechnologyisgenerallyexportedfromtheU.S.EuropeorJapan;thepatentsskillsandabilitytomanufactureremaininthehandsofafewindustrializedcountries.Itisalsoexpensiveandimportedproductsandservicesmustthereforebeboughtoncredit—creditusuallyprovidedbytheverycountrieswhosecompaniesstandtogain.Furthermorewhennewtechnologyisintroducedthereisoftentoolowalevelofexpertisetoexploititfornativedevelopment.Thismeansthatwhilelocalelitesforeigncommunitiesandsubsidiariesoftransnationalcorporationsmaybenefitthosewhoselivesdependonaccesstotheinformationaredeniedit.Whydoestheauthorsaythattheelectroniceconomymayhaveadestructiveimpactondevelopingcountries
Rewardsandpunishmentsareusedindifferentwaysbydifferentcommunitiestomaintainsocialorderandpreserveculturalvalues.Inallculturesparentsmustteachtheirchildrentoavoiddangerandtoobservethecommunity’smoralprecepts.Adultsalsoconditioneachother’sobservanceofsocialnormsusingmethodsrangingfrommildformsofcensuresuchaslookingawaywhensomeonemakesaninappropriateremarktoimprisoningorexecutingindividualsforbehaviorconsidereddeviantordangerous.ThecaningofAmericanteenagerMichaelFayinSingaporeforvandalismin1994broughtwidemediaattentiontoculturaldifferencesintheapplicationofpunishment.FacedwithincreasingviolenceathomemanyAmericansendorsedSingapore’suseofcorporalpunishmenttomaintainsocialorder.WasFay’spunishmenteffectiveWhetherhesubsequentlyavoidsvandalismisunknownbutthepunishmentdidapparentlyleadtohisavoidanceofSingapore—whichheleftpromptly.Theoperanttechniquessocietiesusetomaintainsocialcontrolvaryinpartwiththedangersandthreatsthatconfrontthem.TheGusiiofKenyawithahistoryoftribalwarfarefacethreatsnotonlyfromoutsidersbutalsofromnaturalforcesincludingwildanimals.Gusiiparentstendtorelymoreonpunishmentandfearthanonrewardsinconditioningappropriatesocialbehaviorintheirchildren.Caningfooddeprivationandwithdrawingshelterandprotectionarecommonformsofpunishment.IncontrasttheMixtecansofJuxtlahuacaMexicoareahighlycohesivecommunitywithlittleinternalconflictandsocialnormsthatencouragecooperation.TheirsocialpatternsappearadaptivefortheMixtecansaredominatedbythenearbySpanishMexicanswhocontroltheofficialgovernmentandmanyeconomicresourcesintheirregion.TheMixtecansdonotgenerallyimposefinesorjailsentencesorusephysicalpunishmenttodeteraggressionineitheradultsorchildren.Rathertheytendtorelyonsoothingpersuasion.Socialostracismisthemostfearedpunishmentandsocialtieswithinthecommunityareverystrongsoresponsesthatreinforcethesetiesareeffectiveinmaintainingsocialorder.IntheUnitedStatesfearofsocialostracismorstigmawasonceamorepowerfulforceinmaintainingcontroloverantisocialbehaviorespeciallyinsmallcommunities.Todayevenimprisonmentdoesnotappeartobeanadequatedeterrenttomanyformsofcrimeespeciallyviolentcrime.Althoughonereasonistheinconsistentapplicationofpunishmentanothermaybethefactthatimprisonmentnolongercarriestheintensestigmaitoncehadsothatprisonisnolongerasaneffectivepunishment.Accordingtothepassagewhatisauniversalculturalnorminmaintainingsocialorder
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 6
Directions:Writeanessayof160-200wordsbasedonthefollowingdrawings.Inyouressayyoushould: 1describethepicturesbriefly 2makebothpositiveandnegativecommentsandthen 3giveyourcomments. YoushouldwriteneatlyonANSWERSHEET2.
Collegegraduatesarenowleavingschoolwithnotonlyadiplomabutalsowithmoredebtthaninanyotherperiodinhistory.AccordingtotheCollegeBoardaveragefinancialaidperfulltimeequivalentstudentadjustedforinflationhasalmostdoubledinthelastdecade.Additionallynotonlyistheaveragestudentdebtloadhigherbutalsothenumberofloansoriginatedincreasedbynearlyfourfold.Thusstudentlendinghasincreasedinbreadthaswellasdepthdoublyimpactingthefinancialsituationsofthosestudentswhomustdependonstudentloanstofinancetheireducation.Furthermorethesefiguresnodoubtunderstatethetruelevelofindebtednessincurredbystudentsandtheirfamiliessincesomeundoubtedlyfinancepartoftheireducationandlivingexpensesthroughtheuseofconsumerloanshomeequityloansorcreditcards.Thusthealreadyhugeburdenofstudentloandebtincurredbystudentsandtheirfamiliesisexacerbatedbyfinancialobligationsfromothersources.Thissituationistheoutcomeofaprecariouscombinationofeasycreditthankstocardissuerswhoareeagertotapintothislucrativemarketfinancialnaivetéonthepartofstudentsandasenseonbothsidesthatifworsecomestoworsemommyanddaddywillstepinandsetthingsright.Allcombinetomakecreditatemptingluretostudentsstrappedforcash.Whilecreditstillremainavirtualelementforthefinancingofmanystudents’educationatexpensivecollegesitsimplicationsmustcarefullyweighedandconsideredlestthecash-poorstudentfindhimselfwithmorethathebargainedfor.MoststudentsintheUnitedStatesattendcollegeswhosetuitiondoesnotexceed$15000however.Neverthelessrisingpricescombinedwithstagnantincomegainsamonglow-andmoderate-incomefamilieshavemadeitdifficultifnotimpossibleforastudentfromafamilyofsuchanincomelevelastudentwhohasthemosttogainfromacollegeeducationtoattendcollegewithoutsignificantlyaddingtothefinancialburdenofhisorherfamily.Whilestudentloansstillremainavitalelementforthefinancingofmanystudents’educationatexpensivecollegesitsimplicationsmustbecarefullyweighedandconsideredlestthecash-poorstudentfindhimselfwithmorethanhebargainedfor.InParagraph1...studentlendinghasincreasedinbreadthaswellasdepthmeans
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 8
Collegegraduatesarenowleavingschoolwithnotonlyadiplomabutalsowithmoredebtthaninanyotherperiodinhistory.AccordingtotheCollegeBoardaveragefinancialaidperfulltimeequivalentstudentadjustedforinflationhasalmostdoubledinthelastdecade.Additionallynotonlyistheaveragestudentdebtloadhigherbutalsothenumberofloansoriginatedincreasedbynearlyfourfold.Thusstudentlendinghasincreasedinbreadthaswellasdepthdoublyimpactingthefinancialsituationsofthosestudentswhomustdependonstudentloanstofinancetheireducation.Furthermorethesefiguresnodoubtunderstatethetruelevelofindebtednessincurredbystudentsandtheirfamiliessincesomeundoubtedlyfinancepartoftheireducationandlivingexpensesthroughtheuseofconsumerloanshomeequityloansorcreditcards.Thusthealreadyhugeburdenofstudentloandebtincurredbystudentsandtheirfamiliesisexacerbatedbyfinancialobligationsfromothersources.Thissituationistheoutcomeofaprecariouscombinationofeasycreditthankstocardissuerswhoareeagertotapintothislucrativemarketfinancialnaivetéonthepartofstudentsandasenseonbothsidesthatifworsecomestoworsemommyanddaddywillstepinandsetthingsright.Allcombinetomakecreditatemptingluretostudentsstrappedforcash.Whilecreditstillremainavirtualelementforthefinancingofmanystudents’educationatexpensivecollegesitsimplicationsmustcarefullyweighedandconsideredlestthecash-poorstudentfindhimselfwithmorethathebargainedfor.MoststudentsintheUnitedStatesattendcollegeswhosetuitiondoesnotexceed$15000however.Neverthelessrisingpricescombinedwithstagnantincomegainsamonglow-andmoderate-incomefamilieshavemadeitdifficultifnotimpossibleforastudentfromafamilyofsuchanincomelevelastudentwhohasthemosttogainfromacollegeeducationtoattendcollegewithoutsignificantlyaddingtothefinancialburdenofhisorherfamily.Whilestudentloansstillremainavitalelementforthefinancingofmanystudents’educationatexpensivecollegesitsimplicationsmustbecarefullyweighedandconsideredlestthecash-poorstudentfindhimselfwithmorethanhebargainedfor.Thetextismainlyabout
Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5.a Chronicinsomniaisamajorpublichealthproblem.Andtoomanypeopleareusing1therapiesevenwhilethereareafewtreatmentsthatdowork.MillionsofAmericans2awakeatnightcountingsheeporhaveastiffdrinkor3anpillhopingitwillmakethemsleepy.4expertsagreeallthatself-medicatingisabadideaandthecausesofchronicinsomniaremain5. Almostathirdofadultshavetroublesleepingandabout10percenthave6ofdaytimeimpairmentthatsignaltrueinsomnia.But7thecomplaintsscientistsknowsurprisinglylittleaboutwhatcauseschronicinsomniaitshealthconsequencesandhowbesttotreatitapanelofspecialists8togetherbytheNationalInstitutesofHealthconcludedWednesday.Thepanelcalled9abroadrangeofresearchintoinsomnia10thatifscientistsunderstoodits11causestheycoulddevelopbettertreatments. Mostbutnotallinsomniaisthoughtto12otherhealthproblemsfromarthritisanddepressiontocardiovasculardisease.Thequestionofteniswhethertheinsomniacamefirstorwasaresultoftheotherdiseasesandhowtroublesleepingin13complicatesthoseotherproblems.Otherdiseases14theriskofinsomniaseemstoincreasewithageandtobemore15amongwomenespeciallyaftertheir50s.Smokingcaffeineandnumerous16drugsalsoaffectsleep. TheNIHisspendingabout$200millionthisyearonsleep-relatedresearchsome17tospecificdisordersandothers18theunderlyingscientificlawsthatcontrolthenervoussystemofsleep.Theagencywas19thepane’sreviewbeforedecidingwhatadditionalworkshouldbe20atinsomnia. 2
OneofthemostpressingchallengesthattheUnitedStates—andindeedtheworld—willfaceinthenextfewdecadesishowtoalleviatethegrowingstressthathumanactivitiesareplacingontheenvironment.Theconsequencesarejusttoogreattoignore.Wildlifehabitatsarebeingdegradedordisappearingaltogetherasnewdevelopmentstakeupmoreland.PlantandanimalspeciesarebecomingextinctatagreaterratenowthanatanytimeinEarth’shistory.Asmanyas30percentoftheworld’sfishstocksareoverexploited.Andthelistgoeson.Yetthereisreasontohavehopeforthefuture.Advancesincomputingpowerandmolecularbiologyareamongthetremendousincreasesinscientificcapabilitythatarehelpingresearchersgainabetterunderstandingoftheseproblems.Recentdevelopmentsinscienceandtechnologycouldprovidethebasisforsomemajorandtimelyactionsthatwouldimproveourunderstandingofhowhumanactivitiesaffecttheenvironment.Onepriorityforresearchisimprovinghydrologicalforecasting.Ithasbeenestimatedthattheworld’swaterusecouldtripleinthenexttwodecades.AlreadywidespreadwatershortageshaveoccurredinpartsofChinaIndiaNorthAfricaandtheArabianPeninsula.TheneedforwateralsoistakingitstollonfreshwaterecosystemsintheUnitedStates.Only2percentofthenation’sstreamsareconsideredingoodconditionandcloseto40percentofnativefishspeciesareraretoextinct.Usingavarietyofnewremotesensingtoolsscientistscanlearnmoreabouthowprecipitationaffectswaterlevelshowsurfacewaterisgeneratedandtransportedandhowchangesinthelandscapeaffectwatersupplies.Topreventoutbreaksofinfectiousdiseasesinplantsanimalsandhumansmorestudyisneededonhowpathogensparasitesanddisease-carryingspecies—aswellashumansandotherspeciestheyinfect—areaffectedbychangesintheenvironment.Theoveruseofantibioticsbothinhumansandinfarmanimalshascontributedtothegrowthofantibiotic-resistantmicroorganisms.Researcherscantakeadvantageofnewtechnologiesingeneticsandcomputingtobettermonitorandpredicttheeffectsthatenvironmentalchangesmighthaveondiseaseoutbreaks.HumanshavemadealterationstoEarth’ssurface—suchastropicaldeforestationreductionofsurfaceandgroundwaterandmassivedevelopment—sodramaticthattheyapproachthelevelsoftransformationthatoccurredduringglacialperiods.Suchalterationscausechangesinlocalandregionalclimateandwilldeterminethefutureofagriculture.Recentadvancesindatacollectionandanalysisshouldbeusedtodocumentandbetterunderstandthecausesandconsequencesofchangesinlandcoveranduse.Thelastparagraphimpliesthat
Relativitytheoryhashadaprofoundinfluenceonourpictureofmatterbyforcingustomodifyourconceptofaparticleinanessentialway.46Inclassicalphysicsthemassofanobjecthadalwaysbeenassociatedwithanindestructiblematerialsubstancewithsomestuffofwhichallthingswerethoughttobemade.Relativitytheoryshowedthatmasshasnothingtodowithanysubstancebutisaformenergy.Energyhoweverisadynamicquantityassociatedwithactivityorwithprocesses.47Thefactthatthemassofaparticleisequivalenttoacertainofenergymeansthattheparticlecannolongerbeseenasastatic_objectbuthastobeconceivedasadynamicpatternaprocessinvolvingtheenergywhichmanifestitselfastheparticle’smass.48ThisnewviewofparticleswasinitiatedbyDiracwhenheformulatedarelativisticequationdescribingthebehaviorofelectrons.Dirac’stheorywasnotonlyextremelysuccessfulinaccountingforthefinedetailsofatomicstructurebutalsorevealedafundamentalsymmetrybetweenmatterandanti-matter.Itpredictedtheexistenceofananti-matterwiththesamemassastheelectronbutwithanoppositecharge.ThispositivelychargedparticlenowcalledthepositronwasindeeddiscoveredtwoyearsafterDirachadpredictedit.Thesymmetrybetweenmatterandanti-matterimpliesthatforeveryparticlethereexistsanantiparticleswithequalmassandoppositecharge.Pairsofparticlesandantiparticlescanbecreatedifenoughenergyisavailableandcanbemadetoturnintopureenergyinthereverseprocessofdestruction.49TheseprocessesofparticlecreationanddestructionhadbeenpredictedfromDirac’stheorybeforetheywereactuallydiscoveredinnatureandsincethentheyhavebeenobservedmillionsoftimes.Thecreationofmaterialparticlesfrompureenergyiscertainlythemostspectaculareffectofrelativitytheoryanditcanonlybeunderstoodintermsoftheviewofparticlesoutlinedabove.50Beforerelativisticparticlephysicstheconstituentsofmatterhadalwaysbeenconsideredasbeingeitherelementaryunitswhichwereindestructibleandunchangeableorascompositeobjectswhichcouldbebrokenupintotheirconstituentparts.Andthebasicquestionwaswhetheronecoulddividematteragainandagainorwhetheronewouldfinallyarriveatsomesmallestindivisibleunits.
Cyberspacedatasuperhighwaysmultimedia—forthosewhohaveseenthefuturethelinkingofcomputerstelevisionandtelephoneswillchangeourlivesforever.Yetforallthetalkofaforthcomingtechnologicalutopialittleattentionhasbeengiventotheimplicationsofthesedevelopmentsforthepoor.AswithallnewhightechnologywhiletheWestconcernsitselfwiththehowthequestionofforwhomisputasideonceagain.Economistsareonlynowrealizingthefullextenttowhichthecommunicationsrevolutionhasaffectedtheworldeconomy.Informationtechnologyallowstheextensionoftradeacrossgeographicalandindustrialboundariesandtransnationalcorporationstakefulladvantageofit.Termsoftradeexchangeandinterestratesandmoneymovementsaremoreimportantthantheproductionofgoods.Theelectroniceconomymadepossiblebyinformationtechnologyallowsthehavestoincreasetheircontrolonglobalmarkets—withdestructiveimpactonthehave-nots.Forthemtheresultisinstability.Developingcountrieswhichrelyontheproductionofasmallrangeofgoodsforexportaremadetofeellikesmallpartsintheinternationaleconomicmachine.Asfuturesaretradedoncomputerscreensdevelopingcountriessimplyhavelessandlesscontroloftheirdestinies.SowhataretheoptionsforregainingcontrolOnealternativeisfordevelopingcountriestobuyinthelatestcomputersandtelecommunicationsthemselves—socalleddevelopmentcommunicationsmodernization.Yetthisleadstolong-termdependencyandperhapspermanentconstraintsondevelopingcountries’economies.CommunicationstechnologyisgenerallyexportedfromtheU.S.EuropeorJapan;thepatentsskillsandabilitytomanufactureremaininthehandsofafewindustrializedcountries.Itisalsoexpensiveandimportedproductsandservicesmustthereforebeboughtoncredit—creditusuallyprovidedbytheverycountrieswhosecompaniesstandtogain.Furthermorewhennewtechnologyisintroducedthereisoftentoolowalevelofexpertisetoexploititfornativedevelopment.Thismeansthatwhilelocalelitesforeigncommunitiesandsubsidiariesoftransnationalcorporationsmaybenefitthosewhoselivesdependonaccesstotheinformationaredeniedit.Fromthepassageweknowthatthedevelopmentofhightechnologyisintheinterestsof
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 4
OneofthemostpressingchallengesthattheUnitedStates—andindeedtheworld—willfaceinthenextfewdecadesishowtoalleviatethegrowingstressthathumanactivitiesareplacingontheenvironment.Theconsequencesarejusttoogreattoignore.Wildlifehabitatsarebeingdegradedordisappearingaltogetherasnewdevelopmentstakeupmoreland.PlantandanimalspeciesarebecomingextinctatagreaterratenowthanatanytimeinEarth’shistory.Asmanyas30percentoftheworld’sfishstocksareoverexploited.Andthelistgoeson.Yetthereisreasontohavehopeforthefuture.Advancesincomputingpowerandmolecularbiologyareamongthetremendousincreasesinscientificcapabilitythatarehelpingresearchersgainabetterunderstandingoftheseproblems.Recentdevelopmentsinscienceandtechnologycouldprovidethebasisforsomemajorandtimelyactionsthatwouldimproveourunderstandingofhowhumanactivitiesaffecttheenvironment.Onepriorityforresearchisimprovinghydrologicalforecasting.Ithasbeenestimatedthattheworld’swaterusecouldtripleinthenexttwodecades.AlreadywidespreadwatershortageshaveoccurredinpartsofChinaIndiaNorthAfricaandtheArabianPeninsula.TheneedforwateralsoistakingitstollonfreshwaterecosystemsintheUnitedStates.Only2percentofthenation’sstreamsareconsideredingoodconditionandcloseto40percentofnativefishspeciesareraretoextinct.Usingavarietyofnewremotesensingtoolsscientistscanlearnmoreabouthowprecipitationaffectswaterlevelshowsurfacewaterisgeneratedandtransportedandhowchangesinthelandscapeaffectwatersupplies.Topreventoutbreaksofinfectiousdiseasesinplantsanimalsandhumansmorestudyisneededonhowpathogensparasitesanddisease-carryingspecies—aswellashumansandotherspeciestheyinfect—areaffectedbychangesintheenvironment.Theoveruseofantibioticsbothinhumansandinfarmanimalshascontributedtothegrowthofantibiotic-resistantmicroorganisms.Researcherscantakeadvantageofnewtechnologiesingeneticsandcomputingtobettermonitorandpredicttheeffectsthatenvironmentalchangesmighthaveondiseaseoutbreaks.HumanshavemadealterationstoEarth’ssurface—suchastropicaldeforestationreductionofsurfaceandgroundwaterandmassivedevelopment—sodramaticthattheyapproachthelevelsoftransformationthatoccurredduringglacialperiods.Suchalterationscausechangesinlocalandregionalclimateandwilldeterminethefutureofagriculture.Recentadvancesindatacollectionandanalysisshouldbeusedtodocumentandbetterunderstandthecausesandconsequencesofchangesinlandcoveranduse.WhichofthefollowingdoestheauthorNOTsuggestasanimportantareaforresearch
Cyberspacedatasuperhighwaysmultimedia—forthosewhohaveseenthefuturethelinkingofcomputerstelevisionandtelephoneswillchangeourlivesforever.Yetforallthetalkofaforthcomingtechnologicalutopialittleattentionhasbeengiventotheimplicationsofthesedevelopmentsforthepoor.AswithallnewhightechnologywhiletheWestconcernsitselfwiththe"how"thequestionof"forwhom"isputasideonceagain. Economistsareonlynowrealizingthefullextenttowhichthecommunicationsrevolutionhasaffectedtheworldeconomy.Informationtechnologyallowstheextensionoftradeacrossgeographicalandindustrialboundariesandtransnationalcorporationstakefulladvantageofit.Termsoftradeexchangeandinterestratesandmoneymovementsaremoreimportantthantheproductionofgoods.Theelectroniceconomymadepossiblebyinformationtechnologyallowsthehavestoincreasetheircontrolonglobalmarkets—withdestructiveimpactonthehave-nots. Forthemtheresultisinstability.Developingcountrieswhichrelyontheproductionofasmallrangeofgoodsforexportaremadetofeellikesmallpartsintheinternationaleconomicmachine.As"futures"aretradedoncomputerscreensdevelopingcountriessimplyhavelessandlesscontroloftheirdestinies. SowhataretheoptionsforregainingcontrolOnealternativeisfordevelopingcountriestobuyinthelatestcomputersandtelecommunicationsthemselves—socalled"developmentcommunications"modernization.Yetthisleadstolong-termdependencyandperhapspermanentconstraintsondevelopingcountries’economies. CommunicationstechnologyisgenerallyexportedfromtheU.S.EuropeorJapan;thepatentsskillsandabilitytomanufactureremaininthehandsofafewindustrializedcountries.Itisalsoexpensiveandimportedproductsandservicesmustthereforebeboughtoncredit—creditusuallyprovidedbytheverycountrieswhosecompaniesstandtogain. Furthermorewhennewtechnologyisintroducedthereisoftentoolowalevelofexpertisetoexploititfornativedevelopment.Thismeansthatwhilelocalelitesforeigncommunitiesandsubsidiariesoftransnationalcorporationsmaybenefitthosewhoselivesdependonaccesstotheinformationaredeniedit. Theauthor’sattitudetowardthecommunicationsrevolutionis
1describethecartoonandthemessageconveyedand 2drawaconclusionandgiveyourcommentonthecartoon.
TheTreasurycouldpocket20millionayearinextrafinesoncethecountry’sspeedcameranetworkisexpanded.Motoringorganizationswarnedthatthe1couldbecomeapolltaxonwheels2hugenumberofdrivers.Therecouldbemanymoreincidentsofvandalism3cameras.Thewarningscame4aDailyMailsurveyfoundalmostallthe23policeforcesinEnglandandWaleswereeither5toexpansionplansorconsidering6. Nationwidethenumberofspeedingticketsisexpectedtotreble790millionayear.8theschemepolicekeepsomeofthecashfromfinesto9thecostsoffittingandmaintainingextracamerasand10thatexistingonesalwayshavefilminthem.TherestwillgototheTreasury.BothMinistersandpoliceinsisttheschemeisaimed11atmakingroadssafer.Theypointtotrialsineightareaswhichcutcollisionsbyaquarteranddeathsandseriousinjuriesby12ahalf. Butmotoringorganizationsfearcameraswillbesitedonrelativelysafe13faststretchestocatchasmanydriversaspossible.Someforcesarealsoexpectedto14the"threshold"speedsatwhichcamerasare15totheabsolutelegalminimum-15mphina10mphlimitand26mphina20mphzone.Thiscouldencouragedriverstostareattheirspeedometersinsteadofconcentratingontheroadand16tomoreaccidents.SueNicholsonheadofcampaignsattheRACsaid"Wedon’thaveaproblemwithspeedcameras17.Butwedohaveconcernsabout18theyaresited.Policerisklosingcredibility19motoristsifcamerasareseenasrevenue-raising20safetydevices./ 2
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