計算機科學導論課后問答

1、Explainthefivepartsofaninformationsystem.WhatpartdopeopleplayinthissystemAninformationsystemhasfiveparts:people,procedures,software,hardwareanddata.People:Areenduserswhousecomputertomakethemselvesmoreproductive.Procedures:Specifyrulesorguidelinesforcomputeroperations.Software:Providesstep-by-stepins

2、tructionsforcomputerhardware.Hardware:Processesthedatatocreateinformation.Data:Consistofunprocessedfactsincludingtext,numbers,imageandsounds.Peoplearethemostimportantpartofanyinformationsystem.WhatissystemsoftwareWhatkindsofprogramsareincludedinsystemsoftwareSystemsoftwarehelpsthecomputermanageitsow

3、ninternalresources.Itincludesthreekindsofprograms:operatingsystems,utilitiesanddevicedriversprograms.Defineandcomparebasicandspecializedapplicationsoftware.Describesomedifferenttypesofbasicapplicationsoftware.Describesometypesofspecializedapplications.Basicapplicationsarethekindsofprogramstobeconsid

4、eredcomputercompetent.Specializedapplicationsaremorenarrowlyfocusedonspecificdisciplinesandoccupations.Basicapplicationshavesometypes,suchasbrowser,wordprocessor,spreadsheet,andsoon.Alsospecializedapplicationshavemanytypes,someofthebestknownaregraphics,audioandvideo,multimedia,Webauthoring,andartifi

5、cialintelligenceprograms.Describethedifferenttypesofcomputer.WhatisthemostcommontypeWhatarethetypesofmicrocomputersTherearefourtypesofcomputers:supercomputers,mainframecomputers,minicomputers,andmicrocomputers.Supercomputersarethemostpowerfultypeofcomputer.Mainframecomputersoccupyspeciallywired,air-

6、conditionedrooms,theyarecapableofgreatprocessingspeedsanddatastorage.Minicomputersarerefrigeratorsizedmachines.Microcomputersaretheleastpowerful,yetthemostwidelyusedandfastest-growing,typeofcomputer.Microcomputersarethemostcommontypeofcomputers.Therearefourtypesofmicrocomputers:Desktopcomputers,Note

7、bookcomputers,HandheldcomputersandPDA.WhatisconnectivityHowarethewirelessrevolutionandconnectivityrelatedWhatisacomputernetworkWhatistheInternetWhatistheWebConnectivityisthecapabilityofyoumicrocomputertosharetheinformationwithothercomputers.Wirelessrevolutiondramaticallyaffectconnectivity.Acomputern

8、etworkisacommunicationssystemconnectingtwoormorecomputers.Internetisthelargestnetworkintheworld.TheWebprovidesamultimediainterfacetothenumerousresourcesavailableontheInternet.DiscusstheusesoftheInternet.WhichactivitieshaveyouparticipatedinWhichonedoyouthinkisthemostpopularThemostcommonusesoftheInter

9、netarethefollowing:communicating,shopping,searching,entertainment,education,andsoon.Ihaveparticipatedinalmostallofthem.Ithinkcommunicatingisthemostpopular.Explainthedifferencesbetweenthetwomostcommontypesofproviders.ThetwomostcommontypesofprovidersareNationalandwireless.Nationalserviceprovidersprovi

10、deaccessthroughstandardtelephoneconnections.WirelessserviceprovidersprovideInternetconnectionsforcomputerswithwirelessmodemsandawidearrayofwirelessdevices.Whatarethebasicelementsofane-mailmessageAtypicale-mailmessagehasthreebasicelements:header,messageandsignature.WhatissocialnetworkingDescribetheth

11、reetypesifsocialnetworkingsites.Socialnetworkingisthegroupingofindividualsintospecificgroups.Therearethreebasiccategoriesofsocialnetworkingsites:reuniting,friend-of-a-friendandcommoninterestReunitingsitesaredesignedtoconnectpeoplewhohaveknownoneanotherbuthavelosttouch.Friend-of-a-friendsitesaredesig

12、nedtobringtogethertwopeoplewhodonotknowoneanotherbutshareacommonfriend.Commoninterestsitesbringtogetherindividualsthatsharecommoninterestsorhobbies.Describethedifferenttypesofsearchengines.Givenanexampleofthetypeofsearcheachengineisbestfor.Therearethreetypesofsearchengines:crawler-basedsearchengines

13、,metasearchenginesandspecializedsearchenginesCrawler-basedsearchengines,suchasGoogle,createtheirlistingsautomatically.Metasearchenginesareprogramsthatautomaticallysubmityoursearchrequesttoseveralenginessimultaneously.Themetasearchenginesreceivestheresults,eliminatesduplicates,ordersthehits,andthenpr

14、ovidestheeditedlisttoyou.oneofthebestknownisDogpile.Specializedsearchenginesfocusonsubject-specificWebsites.suchasEnvironment.Explainthedifferencebetweengeneral-purposeandspecial-purposeapplications.General-purposeapplicationarewidelyusedinnearlyeverydisciplineandoccupation.Theyincludewordprocessors

15、,spreadsheets,databasemanagementsystemsandpresentationgraphics.Specializedapplicationincludesthousandsofotherprogramsthataremorenarrowlyfocusedonspecificdisciplinesandoccupations.Discussthecommonfeaturesofmostsoftwareprograms.Describethenewinterfacetowhat-ifanalysisMostapplicationsuseaGUI,usewindows

16、todisplayinformation,andhavemenustopresentcommands.WhatisthedifferencebetweenafunctionandaformulaHowisaformularelatedtowhat-ifanalysisAformulaisaninstructiontocalculateorprocess.Functionsareprewrittenformulas.Aformularelatedtowhat-ifanalysisiscalledrecalculation.WhatarepresentationgraphicsprogramsHo

17、waretheyusedPresentationgraphicsareprogramsthatcombineavarietyofvisualobjectstocreateattractive,visuallyinterestingpresentation.Peopleinavarietyofsettingandsituationsusepresentationgraphicsprogramstomaketheirpresentationsmoreinterestingandprofessional.Whatisthedifferencebetweenanintegratedpackageand

18、asoftwaresuiteWhataretheadvantagesanddisadvantagesodeachAnintegratedpackageisasingleprogramthatprovidesthefunctionalityofawordprocessor,spreadsheet,databasemanager,andmore.Theprimarydisadvantageofanintegratedpackageisthatthecapabilitiesofeachfunctionarenotasextensiveasintheindividualprograms.Theprim

19、aryadvantagesarecostandsimplicity.Asoftwaresuiteisacollectionofseparateapplicationprogramsbundledtogetherandsoldasagroup.ItissignificantlylessexpensivetobuyasuiteofapplicationsthantobuyeachapplicationseparatelyDescribegraphics,includingdesktoppublishers,imageeditors,illustrationprograms,imagegalleri

20、es,andgraphicssuites.Graphicsarewidelyusedtoanalyzedataandtocreateprofessional-lookingpresentations;Desktoppublishersfocusonpagedesignandlayoutandprovidegreaterflexibility;Imageeditorsareprogramsforcreatingandeditingbitmapimages;Illustrationprogramsareusedtocreateandtoeditvectorimages;Imagegalleries

21、arelibrariesofelectronicimages.Theseimagesareusedforawidevarietyofapplicationsfromillustratingtextbookstoprovidingvisualinteresttopresentations;Graphicssuitesaresomecompaniescombiningtheirseparategraphicsprogramsingroups.Discussaudioandvideoeditingsoftware.Audioeditingsoftwareallowsyoutocreateandedi

22、taudioclips,mostsoftwareallowyoutoaddaudioeffectstoyourtracks.Videoeditingsoftwareallowsyoutoreorganize,addeffects,andmoretoyourdigitalvideofootage.WhatismultimediaHowaremultimediapresentationsdevelopedMultimediaistheintegrationofallsortsofmediaintoonepresentation.Thecreationofinteractivemultimediap

23、resentationsfollowsseveralsteps:Plan,Design,CreateandSupport.DescribeWebauthoring,includingWebsitedesignandWebauthoringprograms.CreatingasiteiscalledWebauthoring.Awebsitedesignisaninteractivemultimediaformofcommunication,designingawebsitebeginswithdeterminingthesitesoverallcontent,theoverallsitedesi

24、gniscommonlyrepresentedinagraphicalmap.Morespecializedandpowerfulprograms,calledWebauthoringprograms,aretypicallyusedtocreatesophisticatedcommercialsites.Discussthreeareasofartificialintelligence.Thethreeareasofartificialintelligencearevirtualreality,knowledge-basedsystemsandrobotics.Virtualrealityi

25、sanartificial,orsimulated,realitygeneratedin3-Dbyacomputer.Knowledge-basedsystemsareatypeofartificialintelligencethatusesadatabasetoprovideassistancetousers.Roboticsisthefieldofstudyconcernedwithdevelopingandusingrobots.Describesystemsoftware.WhatarethefourtypesofsystemprogramsSystemsoftwareworkswit

26、hendusers,applicationsoftware,andcomputerhardwaretohandlethemajorityoftechnicaldetails.Itconsistsoffourtypesofprograms:operatingsystems,utilities,devicedriversandlanguagetranslators.WhatarethebasicfunctionsofeveryoperatingsystemWhatarethethreebasicoperatingsystemcategoriesThebasicfunctionsofeveryope

27、ratingsystemare:managingcomputerresources,providingauserinterface,andrunningapplications.Thethreebasicoperatingsystemcategoriesare:embedded,networkandstand-alone.ExplainthedifferencesandsimilaritiesbetweenWindows,MacOS,andLinux.Windowsisbyfarthemostpopularmicrocomputeroperatingsystemtoday.Itcomesina

28、varietyofdifferentversionsandisdesignedtorunwithIntelandIntel-compatiblemicroprocessors.MacOSisnotnearlyaswidelyusedastheWindowsoperatingsystem.Itisapowerful,easy-to-useoperatingsystemthatispopularwithprofessionalgraphicdesigns,desktoppublishers,andmanyhomeusers.WhileWindows,theMacOSareproprietaryop

29、eratingsystems,Linuxisnot.Itisopensourcesoftwarefreeandavailablefrommanysources,includingtheWeb.Discussutilities.WhatarethefivemostessentialutilitiesWhatisautilitiessuiteUtilitiesarespecializedprogramsdesignedtomakecomputingeasier.Thefivemostessentialutilitiesare:troubleshootingordiagnosticprograms,

30、antivirusprograms,uninstallprograms,backupprogramsandfilecompressionprograms.Utilitysuitescombineseveralprogramsintoonepackage.Explaintheroleofdevicedrivers.DiscusstheAddPrinterWizardandWindowsUpdate.Adevicedriverworkswiththeoperatingsystemtoallowcommunicationbetweenthedeviceandtherestofthecomputers

31、ystem.Eachtimethecomputersystemisstarted,theoperatingsystemloadsallofthedevicedriversintomemory.Wheneveranewdeviceisaddedtoacomputersystem,anewdevicedrivermustbeinstalledbeforethedevicecanbeused.AddPrinterWizardprovidesstep-by-stepguidancetoselecttheappropriateprinterdriverandtoinstallthatdriver.Win

32、dowsusesWindowsUpdatetomakereinstallingorupdatingdevicedriverseasily.Describethefourbasictypesofsystemunits.Therearefourbasictypesofsystemunits:Desktopsystemunits,Notebooksystemunits,TabletPCsystemunits,andHandheldcomputersystemunits.Desktopsystemunitstypicallycontainthesystemselectroniccomponentsan

33、dselectedsecondarystoragedevices.Notebooksystemunitsareportableandmuchsmaller.Theycontaintheelectroniccomponents,selectedsecondarystoragedevices,andinputdevice.TabletPCsystemunitsarehighlyportabledevicesthatsupporttheuseofastylusorpentoinputcommandsanddata.Handheldcomputersystemunitsarethesmallestan

34、daredesignedtofitintothepalmofonehand.DescribethetwobasiccomponentsoftheCPU.Thetwobasiccomponentsare:thecontrolunitandthearithmetic-logicunit.Controlunittellstherestofthecomputersystemhowtocarryoutaprogramsinstructions.Arithmetic-logic logical.unit performs two types of operationsarithmeticandWhatar

35、ethedifferencesandsimilaritiesbetweenthethreetypesofmemoryTherearethreetypesofmemorychips:RAM,ROM,andCMOS.RAMchipsholdtheprogramanddatathattheCPUispresentlyprocessing,everythinginmosttypesofRAMislostassoonasthemicrocomputeristurnedofforapowerfailure.ROMchipshaveprogramsbuiltintothematthefactory.ROMc

36、hipsarenotvolatileandcannotbechangedbytheuser.CMOSchipprovidesflexibilityandexpandabilityforacomputersystem.Itcontainsessentialinformationthatisrequiredeverytimethecomputersystemisturnedon.Itispoweredbyabatteryanddoesnotloseitscontentswhenthepoweristurned.Itscontentscanbechangedtoreflectchangesinthe

37、computersystem.Identifyfiveexpansioncardsanddescribethefunctionofeach.Fiveexpansioncardsare:graphicscards,soundcards,modemcards,NICandTVtunercards.Graphicscardsconnectthesystemboardtothecomputersmonitor,theyconverttheinternalelectronicsignalstovideosignalssotheycanbedisplayedonthemonitor.Soundcardsa

38、cceptaudioinputfromamicrophoneandconvertitintoaformthatcanbeprocessedbythecomputer.Theyalsoconvertinternalelectronicsignalstoaudiosignals.Modemcardsallowdistantcomputerstocommunicatewithoneanotherbyconvertingelectronicsignalsfromwithinthesystemunitintoelectronicsignalsthatcantravelovertelephonelines

39、andothertypesofconnections.NICareusedtoconnectacomputertooneormoreothercomputers.TVtunercardscanchangestheTVsignalintoonethatcanbedisplayedonyoumonitor.Identifyanddescribefourstandardportsandtwospecializedports.Fourstandardportsare:serialports,parallelports,universalserialbusportsandFireWireports.Se

40、rialportsareoftenusedtoconnectamouse,keyboard,modem,andmanyotherdevicestothesystemunit.Parallelportsareusedtoconnectexternaldevicesthatneedtosendorreceivealotofdataoverashortdistance.USBportsaregraduallyreplacingserialandparallelports.FireWireportsprovideconnectionstospecializedFireWiredevices.Defin

41、einputandoutputdevices.Inputisanydataorinstructionsthatareusedbyacomputer.Inputdevicesarehardwareusedtotranslatewhatpeopleunderstandintoaformthatcomputerscanprocess.Describethethreecategoriesofoutputdevices.Thereareawidelyofdifferentpointingdevicesincludingthemouse,joystick,touchscreen,lightpen,ands

42、tylus.Amousecontrolsapointerthatisdisplayedonthemonitor.Ajoystickisthemostpopularinputdeviceforcomputergames.Youcontrolgameactionsbyvaryingthepressure,speed,anddirectionofthejoystick.Atouchscreenisaparticularkindofmonitorwithaclearplasticouterlayer.Alightpenisalight-sensitivepen-likedevice.Astylusac

43、tswiththecomputerthroughhandwritingrecognitionsoftware.Therearethreetypesofscanningdevices:opticalscanners,cardreaders,barcodereaders,andcharacterandmarkrecognitiondevices.Anopticalscanneracceptsdocumentsconsistingoftextand/orimagesandconvertsthemtomachinereadableform.Cardreadersinterpretencodedinfo

44、rmation.Barcodereadersareeitherhandheldwandreadersorplatformscanners.Characterandmarkrecognitiondevicesarescannersthatareabletorecognizespecialcharactersandmarks.Imagecapturingdevicesincludedigitalcamerasanddigitalvideocameras.Digitalcamerascapturestillimages.Digitalvideocamerascapturemotion.Audioin

45、putcantakemanyformsincludingthehumanvoiceandmusic.Voicerecognitionsystemsacceptvoicecommandstocontrolcomputeroperationsandtocreatedocument.MIDIisastandardforconnectingmusicalinstrumentstothesystemunit.Describethethreecategoriesifoutputdevices.Themostwidelyusedoutputdevicesaremonitors,printersandaudi

46、ooutput.Monitorspresentvisualimagesoftextandgraphics.Printerstranslateinformationthathasbeenprocessedbythesystemunitandpresenttheinformationonpaper.Audiooutputdevicestranslateaudioinformationfromthecomputerintosoundsthatpeoplecanunderstand.Defineoutputanoutputdevices.Outputisprocesseddataorinformati

47、on.Outputdevicesarehardwareusedtotranslateinformationthathasbeenprocessedbythesystemunitintoaformthathumanscanunderstands.WhatarecombinationinputandoutputdevicesDescribefoursuchdevices.Devicescombinefeaturesofinputdevicessuchasscannerswithfeaturesofoutputdeviceslikeprintersarecalledcombinationinputa

48、ndoutputdevices.Combinationdevicesincludefaxmachines,multifunctiondevices,Internettelephones,andterminals.Afaxmachineisastandardtoolinnearlyeveryoffice.Multifunctiondevicescombinethecapabilitiesofascanner,printer,fax,andcopyingmachine.Internettelephonesarespecializedinputandoutputdevicesforreceiving

49、andsendingvoicecommunication.Terminalsareinputandoutputdevicethatconnectyoutoamainframeorothertypeofcomputer.Discussthetraditionalandhigh-capacityfloppydisksThetraditionalfloppydiskisthe3-inchdisk.Theyhaveathinexteriorjacketmadeofhardplastictoprotecttheflexiblediskinside.Thehighcapacityfloppydisksar

50、e3inchesindiameter.Theyareabletostoremoreinformation,arethicker,andrequirespecialdiskdrives.WhatarethethreetypesofharddisksDescribethreewaystoimproveharddiskperformance.Therearethreetypesofharddisks:Internalharddisk,hard-diskcartridge,andhard-diskpack.Threewaystoimprovetheperformanceofharddisksaredi

51、skcaching,redundantarraysofinexpensivedisks,andfilecompression/decompression.Diskcachingimproveshard-diskperformancebyanticipatingdataneeds.Redundantarraysofinexpensivedisksimproveperformancebyexpendingexternalstorage,improvingaccessspeed,andprovidingreliablestorage.Filecompressionandfiledecompressi

52、onincreasestoragecapacitybyreducingtheamountofspacerequiredtostoredataandprograms.WhatarethetwomostcommonopticaldiscformatsWhatishidefDescribethebasictypesforeachformat.ThetwomostcommonopticaldiscformatsareCDandDVD.Hidefisthenextgenerationofopticaldiscs.TherearefourbasictypesofCDs:readonly,writeonce

53、,rewritable,andPictureandPhotoCDs.ReadonlyCDscannotbewrittenonorerasedbytheusers,theyareusedtodistributelargedatabases,references,andlargesoftwareapplicationpackages.WriteonceCDscanbewrittentoonce,theyareusedtoarchivedataandtorecordmusicdownloadfromtheInternet.RewritableCDsaresimilartowriteonceCDsex

54、ceptthatthediskssurfaceisnotpermanentlyalteredwhendataisrecorded.PictureandPhotoCDsuseaspecialformatdevelopedbyEastmanKodaktostoredigitalimages.TherearethreetypesofDVDs:readonly,writeonce,andrewriteable.ReadonlyDVDscanprovideovertwohoursofveryhigh-qualityvideoandsoundcomparabletothatfoundinmotionpic

55、turetheatres.WriteonceDVDsaretypicallyusedtocreatepermanentarchivesforlargeamountsofdataandtorecordvideos.RewriteableDVDsarecompetingrewriteableformats.Discusssolid-statestorage,Internetharddrives,andmagnetictape.WhataretheadvantagesanddisadvantagesofeachSolid-statestoragedoesnothavemovingparts.Inte

56、rnetdrivesusetheInternettostoredataandinformation.Magnetictapeprovidessequentialaccessforbackup.Solid-statestorageismoreexpensivethantheothers,itismorereliableandrequireslesspower.InternetdrivesarelowcostandtheflexibilitytoaccessinformationfromanylocationusingtheInternet.Accessspeedisslower.Magnetic

57、tapesprovideslowersequentialaccess.Itisaneffectiveandcommonlyusedtoolforbackingupdata.Discussmassstorage,enterprisestoragesystem,andmassstoragedevices.Massstoragereferstothestorageoflargeamountsofdatainapersistingandmachine-readablefashion.Enterprisestoragesystemsarethecomputerstoragesystemsdesigned

58、forlarge-scale,high-technologyenvironmentsofthemodernstorageDeviceshavebeendescribedasmassstorageincludetapelibraries,RAIDsystems,harddiskdrives,magnetictapedrives,opticaldiscdrives,magneto-opticaldiscdrives,drummemory,floppydiskdrives,punchedtapeandholographicmemory.Defineanddiscussconnectivity,the

59、wirelessrevolution,andcommunications.Connectivityisaconceptrelatedtousingcomputernetworkstolinkpeopleandresources.Thesinglemostdramaticchangeinconnectivityandcommunicationsinthepastfiveyearshasbeenthewidespreaduseofmobileorwirelesstelephones.Thiswirelesstechnologyallowsindividualstostayconnectedwith

60、oneanotherfromalmostanywhereatanytime,therevolutionisjustbeginning.Communicationsystemstransmitdatafromonelocationtoanother.Everycommunicationsystemhasfourbasicelements:sendingandreceivingdevices,communicationchannel,connectiondevices,anddatatransmissionspecifications.Identifyanddescribethevariousph