专业外语下 教案与讲义

第一讲computernetwork第一部分课程安排一、教学目的：掌握新的专业词汇及短语。二、教学要求：能够结合专业知识理解课文内容，独立完成课后习题。三、教学重点：1、新词汇及短语的理解与记忆；2、课文的理解四、教学难点：五、教学方式：采用教师与学生互动的方式，提问问题，鼓励学生积极思考六、授课内容和课时安排：七、课后练习：八、作业安排：九、本讲小结：十、课后纪要：第二部分授课内容ComputerNetworkAcomputernetworkiscomposedofmultiplecomputersconnectedtogetherusingatelecommunicationsystemforthepurposeofsharingdata,resourcesandcommunication.Forinstance,ahomecomputernetworkmayconsistoftwoormorecomputersthatsharefilesandaprinterusingthenetwork.Thesizeandscalabilityofanycomputernetworkaredeterminedbythehardwareusedaswellaswhichprotocolsarebeingimplemented.1.DefinitionExpertsinthefieldofnetworkingdebatewhethertwocomputersthatareconnectedtogetherusingsomeformofcommunicationsmediumconstituteanetwork.Therefore,someworksstatethatanetworkrequiresthreeconnectedcomputers.Onesuchsource,“Telecommunications:GlossaryofTelecommunicationTerms”statesthatacomputernetworkis“Anetworkofdataprocessingnodesthatareinterconnectedforthepurposeofdatacommunication”.Theterm“network”beingdefinedinthesamedocumentas“Aninterconnectionofthreeormorecommunicatingentities”.Acomputerconnectedtoanon-computerdevice(e.g.,networktoaprinterviaanEthernetlink)mayalsorepresentacomputernetwork,althoughthisarticledoesnotaddressthisconfiguration.Thisarticleusesthedefinitionwhichrequirestwoormorecomputerstobeconnectedtogethertoformanetwork.Thesamebasicfunctionsaregenerallypresentinthiscaseaswithlargernumbersofconnectedcomputers.Inorderforanetworktofunction,itmustmeetthreebasicrequirements,itmustprovideconnections,communicationsandservices.Connectionsreferstothehardware,communicationsisthewayinwhichthedevicestalktoeachother,andservicesarethethingswhicharesharedwiththerestofthenetwork.2.ClassificationofComputerNetworks2.1BynetworklayerComputernetworksmaybeclassifiedaccordingtothenetworklayeratwhichtheyoperateaccordingtosomebasicreferencemodelsthatareconsideredtobestandardsintheindustrysuchastheseven-layerOSIReferenceModelandthefive-layerTCP/IPmodel.2.2ByscaleComputernetworksmaybeclassifiedaccordingtothescaleorextentofeachofthenetwork,forexampleasapersonalareanetwork(PAN),localareanetwork(LAN),campusareanetwork(CAN),metropolitanareanetwork(MAN),orwideareanetwork(WAN).2.3ByconnectionmethodComputernetworksmaybeclassifiedaccordingtothetechnologythatisusedtoconnecttheindividualdevicesinthenetworksuchasHomePNA,powerlinecommunication,Ethernet,orwirelessLAN.2.4ByfunctionalrelationshipComputernetworksmaybeclassifiedaccordingtothefunctionalrelationshipswhichexistbetweentheelementsofthenetwork,forexampleactivenetworking,client-serverandpeer-to-peer(workgroup)architectures.2.5BynetworktopologyComputernetworksmaybeclassifiedaccordingtothenetworktopologyuponwhichthenetworkisbased,suchasbusnetwork,starnetwork,ringnetwork,meshnetwork,star-busnetwork,treeorhierarchicaltopologynetwork,etc.Topologycanbearrangedinageometricarrangement.Networktopologiesarelogicallayoutsofthenetwork.Theterm“logical”usedheremarksagreatsignificant.Thatmeansnetworktopologiesdependnotonthe“physical’layoutofthenetwork.Nomatterthatcomputersonanetworkareplacedinalinearformat,butiftheyconnectedviaahubtheyareformingastartopology,notthebustopology.Andhereistheimportantfactorwherenetworksdiffer,visuallyandoperationally.2.6ByservicesprovidedComputernetworksmaybeclassifiedaccordingtotheserviceswhichtheyprovide,suchasstorageareanetworks,serverfarms,processcontrolnetworks,value-addednetwork,wirelesscommunitynetwork,etc.2.7ByprotocolComputernetworksmaybeclassifiedaccordingtothecommunicationsprotocolthatisbeingusedonthenetwork.3.TypesofNetworksBelowisalistofthemostcommontypesofcomputernetworksinorderofscale.3.1PersonalAreaNetwork(PAN)Apersonalareanetworkisacomputernetworkusedforcommunicationamongcomputerdevices(includingtelephonesandpersonaldigitalassistants)closetooneperson.Thedevicesmayormaynotbelongtothepersoninquestion.ThereachofaPANistypicallyafewmeters.PANscanbeusedforcommunicationamongthepersonaldevicesthemselves(intrapersonalcommunication),orforconnectingtoahigherlevelnetworkandtheInternet(anuplink).PersonalareanetworksmaybewiredwithcomputerbusessuchasUSBandFireWire.Awirelesspersonalareanetwork(WPAN)canalsobemadepossiblewithnetworktechnologiessuchasIrDAandBluetooth.3.2LocalAreaNetwork(LAN)Localareanetworkisanetworkcoveringasmallgeographicarea,likeahome,office,orbuilding.CurrentLANsaremostlikelytobebasedonEthernettechnology.ThedefiningcharacteristicsofLANs,incontrasttoWANs(wideareanetworks),includetheirmuchhigherdatatransferrates,smallergeographicrange,andlackofaneedforleasedtelecommunicationlines.3.3CampusAreaNetwork(CAN)CampusareanetworkisanetworkthatconnectstwoormoreLANsbutthatislimitedtoaspecific(possiblyprivate)geographicalareasuchasacollegecampus,industrialcomplex,oramilitarybase.ACANmaybeconsideredatypeofMAN(metropolitanareanetwork),butisgenerallylimitedtoanareathatissmallerthanatypicalMAN.3.4MetropolitanAreaNetwork(MAN)MANisanetworkthatconnectstwoormoreLANsorCANstogetherbutdoesnotextendbeyondtheboundariesoftheimmediatetown,city,ormetropolitanarea.Multiplerouters,switcher&hubsareconnectedtocreateaMAN.3.5WideAreaNetwork(WAN)WANisadatacommunicationsnetworkthatcoversarelativelybroadgeographicareaandthatoftenusestransmissionfacilitiesprovidedbycommoncarriers,suchastelephonecompanies.WANtechnologiesgenerallyfunctionatthelowerthreelayersoftheOSIreferencemodel:thephysicallayer,thedatalinklayer,andnetworklayer.3.6InternetworkInternetworkistwoormorenetworksornetworksegmentsconnectedusingdevicesthatoperateatlayer3(the“network”layer)oftheOSIBasicReferenceModel,suchasarouter.Anyinterconnectionamongorbetweenpublic,private,commercial,industrial,orgovernmentalnetworksmayalsobedefinedasaninternetwork.3.6.1InternetItisaspecificinternetwork,consistingofaworldwideinterconnectionofgovernmental,academic,public,andprivatenetworksbasedupontheAdvancedResearchProjectsAgencyNetwork(ARPANET)developedbyARPAoftheU.S.Defense–alsohometotheWorldWideWeb(WWW)andreferredtoasthe“Internet”withacapitalTtodistinguishitfromothergenericinternetworks.3.6.2ExtranetExtranetisanetworkorinternetworkthatislimitedinscopetoasingleorganizationorentitybutwhichalsohaslimitedconnectionstothenetworksofoneormoreotherusually,butnotnecessarily,trustedorganizationsorentities.Forexample,acompany’scustomersmaybeprovidedaccesstosomepartofitsintranetthuslycreatinganextranetwhileatthesametimethecustomersmaynotbeconsidered“trusted”fromasecuritystandpoint.Technically,anextranetmayalsobecategorizedasaCAN,MAN,WAN,orothertypeofnetwork,although,bydefinition,anextranetcannotconsistofasingleLAN,becauseanextranetmusthaveatleastoneconnectionwithanoutsidenetwork.IntranetsandextranetsmayormaynothaveconnectionstotheInternet.IfconnectedtotheInternet,theintranetorextranetisnormallyprotectedfrombeingaccessedfromtheInternetwithoutproperauthorization.TheInternetitselfisnotconsideredtobeapartoftheintranetorextranet,althoughtheInternetmayserveasaportalforaccesstoportionsofanextranet.4.BasicHardwareComponentsAllnetworksaremadeupofbasichardwarebuildingblockstointerconnectnetworknodes,suchasnetworkinterfacecards(NICs),bridges,hubs,switches,androuters.Inaddition,somemethodofconnectingthesebuildingblocksisrequired,usuallyintheformofgalvaniccable(mostcommonlyCategory5cable).Lesscommonaremicrowavelinks(asinIEEE802.11)oropticalcable(“opticalfiber’)4.1NetworkInterfaceCardsAnetworkcard,networkadapterorNIC(networkinterfacecard),isapieceofcomputerhardwaredesignedtoallowcomputerstocommunicateoveracomputernetwork.Itprovidesphysicalaccesstoanetworkingmediumandprovidesalow-leveladdressingsystemthroughtheuseofMACaddresses.Itallowsuserstoconnecttoeachothereitherbyusingcablesorwirelessly.4.2BridgesAnetworkbridgeconnectsmultiplenetworksegmentsatthedatalinklayer(layer2)oftheOSImodel.Bridgesaresimilartorepeatersornetworkhubs,devicesthatconnectnetworksegmentsatthephysicallayer,andhowever,abridgeworksbyusingbridgingwheretrafficfromonenetworkismanagedratherthansimplyrebroadcasttoadjacentnetworksegments.4.3HubsAhubisapieceofhardwarewhichprovidestheconnectivityofasegmentofanetworkbydirectingtrafficthroughthenetwork.Itdoesthisinarudimentaryway,itsimplycopiesthedatatoalloftheNodesconnectedtothehub.HubsarecommonlyusedtoconnectsegmentsofaLAN.Ahubcontainsmultipleports.Whenapacketarrivesatoneport,itiscopiedtotheotherportssothatallsegmentsoftheLANcanseeallpackets.4.4SwitchesSwitchesarethedeviceofnetworkingthatdirectstraffictothecorrectnodebyfilteringandforwardingpacketsbetweennodes.Switchesoperateatthedatalinklayer(layer2)andsometimesthenetworklayer(layer3)oftheOSIReferenceModelandthereforesupportanypacketprotocol.LANsthatuseswitchestojoinsegmentsarecalledswitchedLANsor,inthecaseofEthernetnetworks,switchedEthernetLANs.Inacircuit-switcheddatanetwork,aswitchisusedtocreateavirtualcircuitbetweenthepairsofendpoints.Thismeansthatitcreatesapathtothedestinationnodefromthesourcenode.4.5RoutersRoutersarethenetworkingdevicethatforwardsdatapacketsalongnetworksbyusingheadersandforwardingtablestodeterminethebestpathtoforwardthepackets.Routersalsoprovideinterconnectivitybetweenlikeandunlikedevicesonthenetwork.Thisisaccomplishedbyexaminingtheheaderofadatapacket.TheyuseprotocolssuchasICMPtocommunicatewitheachotherandconfigurethebestroutebetweenanytwohosts.Arouterisconnectedtoatleasttwonetworks,commonlytwoLANsorWANsoraLANanditsISP’snetwork.Routersareusuallylocatedatgateways,theplaceswheretwoormorenetworksconnect.ManyhouseholdDSLandModemsarealsorouters.NewWordsnetworkn.网络telecommunicationn.电信scalabilityn.可伸缩性protocoln.协议expertn.专家，行家interconnectionn.互连，互相联络classificationn.分类，分级scalen.规模，比例，数值，范围，等级workgroupn.工作组logicaladj.逻辑的，逻辑上的linearadj.线性的hubn.网络集线器，网络中心uplinkn.向上传输，上行线，上行链路firewiren.火线Bluetoothn.蓝牙privateadj.私人的，私有地，专用的extranetn.外联网intranetn.内联网standpointn.立场，观点properadj.正当的，适当的authorizationn.授权，认可portaln.门户，入口microwaven.微波adaptern.适配器addressingn.寻址trafficn.通信量rebroadcastv.&.转播，重播adjacentadj.邻近的，接近的connectivityn.连通的packetn.信息包forwardingn.转发endpointn.端点，终点destinationn.目的地；目的文件，目的单元格interconnectivityn.互联通性gatewayn.门，通路，网关PhrasesBecomposedof由……组成homecomputernetwork家庭计算机网络consistof由……组成referencemodel参考模型powerlinecommunication电力线通信activenetworking主动式网络peer-to-peerarchitecture等体系结构busnetwork总线网starnetwork星型网ringnetwork环型网meshnetwork网状网star-busnetwork星型—总线treetopologynetwork树状拓扑网storageareanetwork存储区域网processcontrolnetwork过程控制网value-addednetwork增值网personaldigitalassistant个人数字助理，缩写为PDAinquestion正被讨论datatransferrate数据传输率leasedtelecommunicationline租用通信线路militarybase军事基地physicallayer物理层datalinklayer数据链路层AbbreviationOSI开放式系统互连（OpenSystemInterconnect）TCP传输控制协议（TransferControlProtocol）IP网际协议（InternetProtocol_PAN个人网络（PersonalAreaNetwork）CAN园区网（CampusAreaNetwork）MAN城域网（MetropolitanAreaNetwork）APPANET阿帕网，美国国防部高级研究计划署计算机网（AdvancedResearchProjectsAgencyNetwork）IEEE(美国)电气电子工程师学会（InstituteforElectricalandElectronicEngineers）MAC媒体访问控制（MediaAccesscontrol）ICMP网间控制报文协议（InternetControlMessagesProtocol）Exercises[EX.1]根据课文内容回答问题Whatisacomputernetwork?Listtheexamplesofcomputernetworksclassifiedbyscale.Howmanycomputernetworksbeclassifiedexceptbyscale?Whatisapersonalareanetwork(PAN)?WhatdoesLANstandfor?WhatarecurrentLANsaremostlikelytobebasedon?WhatdodefiningcharacteristicsofLANsinclude?Whatisahub?Whatarerouters?【EX.2】根据下面的英文解释，写出相应的而英文词汇（1）：Asystemofcomputersinterconnectedbytelephonewiresorothermeansinordertoshareinformation.(2):Thescienceandtechnologyofcommunicationatadistancebyelectronictransmissionofimpulses,asbytelegraph,cable,telephone,radio,ortelevision.(3):Astandardprocedureforregulatingdatatransmissionbetweencomputers.(4):Agroupofusersworkingonacommonprojectandsharingcomputerfiles,oftenoveralocalareanetwork.(5):Inanetwork,adevicejoiningcommunicationlinesatacentrallocation,providingacommonconnectiontoalldevicesonthenetwork.(6):Inreferencetocomputing,especiallyremotecomputersonanetwork,therightgrantedanindividualtousethesystemanddatastoredonit.第二讲DATABASE第一部分课程安排一、教学目的：掌握新的专业词汇及短语。二、教学要求：能够结合专业知识理解课文内容，独立完成课后习题。三、教学重点：1、新词汇及短语的理解与记忆；2、课文的理解四、教学难点：五、教学方式：采用教师与学生互动的方式，提问问题，鼓励学生积极思考六、授课内容和课时安排：七、课后练习：八、作业安排：九、本讲小结：十、课后纪要：第二部分授课内容Database(1)Incomputing,adatabasecanbedefinedasastructuredcollectionofrecordsordatathatisstoredinacomputersothataprogramcanconsultittoanswerqueries.Therecordsretrievedinanswertoqueriesbecomeinformationthatcanbeusedtomakedecisions.Thecomputerprogramusedtomanageandqueryadatabaseisknownasadatabasemanagementsystem(DBMS).Thepropertiesanddesignofdatabasesystemsareincludedinstudyofinformationscience.Theterm“database”originatedwithinthecomputingdiscipline.Althoughitsmeaninghasbeenbroadenedbypopularuse,eventoincludenon-electronicdatabases,thisarticleisaboutcomputerdatabases.Database-likerecordshavebeeninexistencesincewellbeforetheindustrialrevolutionintheformofledgers,salesreceiptsandotherbusinessrelatedcollectionsofdata.Thecentralconceptofadatabaseisthatofacollectionofrecords,orpiecesofinformation.Typically,foragivendatabasethereisastructuraldescriptionofthetypeoffactsheldinthatdatabasethisdescriptionisknownasaschema.Theschemadescribestheobjectsthatarerepresentedinthedatabase,andtherelationshipsamongthem.Thereareanumberofdifferentwaysoforganizingaschema,thatis,ofmodelingthedatabasestructure:theseareknownasdatabasemodels(ordatamodels).Themodelinmostcommonusetodayistherelationalmodel,whichinlayman’stermsrepresentsallinformationintheformofmultiplerelatedtableseachconsistingofrowsandcolumns(thetruedefinitionusesmathematicalterminology).Thismodelrepresentsrelationshipsbytheuseofvaluescommontomorethanonetable.Othermodelssuchasthehierarchicalmodelandthenetworkmodeluseamoreexplicitrepresentationofrelationships.Thetermdatabasereferstothecollectionofrelatedrecords,andthesoftwareshouldbereferredtoasthedatabasemanagementsystemorDBMS.Whenthecontextisunambiguous,however,manydatabaseadministratorsandprogrammersusethetermdatabasetocoverbothmeanings.Manyprofessionalsconsideracollectionofdatatoconstituteadatabaseonlyifithascertainproperties:forexample,ifthedataifmanagedtoensureitsintegrityandquality,ifitallowssharedaccessbyacommunityofusersifithasaschema,orifitsupportsaquerylanguage.However,thereisnoagreeddefinitionoftheseproperties.Databasemanagementsystemsareusuallycategorizedaccordingtothedatamodelthattheysupport:relational,object-relational,network,andsoon.Thedatamodelwilltendtodeterminethequerylanguagesthatareavailabletoaccessthedatabase.AgreatdealoftheinternalengineeringofaDBMS,however,isindependentofthedatamodel,andisconcernedwithmanagingfactorssuchasperformance,concurrency,integrity,andrecoveryfromhardwarefailuresIntheseareastherearelargedifferencesbetweenproducts.Varioustechniquesareusedtomodeldatastructure.Mostdatabasesystemsarebuiltaroundoneparticulardatamodel,althoughitisincreasinglycommonforproductstooffersupportformorethanonemodel.Foranylogicalmodel,variousphysicalimplementationsmaybepossible,andmostproductswillofferusersomelevelofcontrolintuningthephysicalimplementation,sincethechoicesthataremadehaveasignificanteffectonperformance.Anexampleistherelationalmodel:allseriousimplementationsoftherelationalmodelallowthecreationofindexeswhichprovidefastaccesstorowsinatableifthevaluesofcertaincolumnsareknown.1.1FlatmodelThismaynotstrictlyqualifyasadatamodel,asdefinedabove.Theflatortablemodelconsistsofasingle,twodimensionalarrayofdataelements,whereallmembersofagivencolumnareassumedtobesimilarvalues,andallmembersofarowareassumedtoberelatedtooneanother.1.2HierarchicalmodelInahierarchicalmodel,Dataisorganizedintoatree-likestructure,implyingasingleupwardlinkineachrecordtodescribethenesting,andasortfieldtokeeptherecordsinaparticularorderineachsame-levellist.1.3RelationalmodelThreekeytermsareusedextensivelyinrelationaldatabasemodel:relations,attributes,anddomains.Arelationisatablewithcolumnsandrows.ThenamedcolumnsoftherelationarecalledAttributes,andthedomainisthesetofvaluestheattributesareallowedtotake.Thebasicdatastructureoftherelationalmodelisthetable,whereinformationaboutaparticularentity(say,anemployee)isrepresentedincolumnsandrows(alsocalledtuples).Thus,the‘relation”In“relationaldatabase”referstothevarioustablesinthedatabase;arelationisasetoftuples.Thecolumnsenumeratethevariousattributesoftheentity(aspecificemployee)thatisrepresentedbytherelation.Asaresult,eachtupleoftheemployeetablerepresentsvariousattributesofasingleemployee.Allrelations(and,thus,tables)inarelationaldatabasehavetoadheretosomebasicrulestoqualifyasrelationsFirst,theorderingofcolumnsisimmaterialinatable.Second,therecan’tbeidenticaltuplesorrowsinatable.Andthird,eachtuplewillcontainasinglevalueforeachofitsattributes.Arelationaldatabasecontainsmultipletables,eachsimilartotheoneinthe“flat”databasemodel.Oneofthestrengthsoftherelationalmodelisthat,inprinciple,anyvalueoccurringintwodifferentrecords(belongingtothesametableortodifferenttables)impliesarelationshipbetweenthosetworecords.Yet,inordertoenforceexplicitintegrityconstraints,relationshipsbetweenrecordsintablescanalsobedefinedexplicitly,byidentifyingornon-identifyingparent-childrelationshipscharacterizedbyassigningcardinality(1:1,(0)1:M,M:M).Tablescanalsohaveadesignatedsingleattributeorasetofattributesthatcanactasa“key”,whichcanbeusedtouniquelyidentifyeachtupleinthetable.Akeythatcanbeusedtouniquelyidentifyarowinatableiscalledaprimarykey.KeysarecommonlyusedtojoinorcombinedatafromtwoormoretablesForexample,anEmployeetablemancontainacolumnnamedlocationwhichcontainsavaluethatmatchesthekeyofalocationtable.Keysarealsocriticalinthecreationofindices,whichfacilitatefastretrievalofdatafromlargetables.Anycolumncanbeakey,ormultiplecolumnscanbegroupedtogetherintoacompoundkey.Itisnotnecessarytodefineallthekeysinadvance,columncanbeusedasakeyevenifitwasnotoriginallyintendedtobeone.2.RelationaloperationsUsers(orprograms)requestdatafromarelationaldatabasebysendingitaquerythatiswritteninaspeciallanguage,usuallyadialectofSQL.AlthoughSQLwasoriginallyintendedforend-users,itismuchmorecommonforSQLqueriestobeembeddedintosoftwarethatprovidesaneasieruserinterface.ManyWebsites,suchasWikipedia,performSQLquerieswhengeneratingpages.Inresponsetoquery,thedatabasereturnsaresultset,whichisjustalistofrowscontainingtheanswers.Thesimplestqueryisjusttoreturnalltherowsfromatable,butmoreoften,therowsarefilteredinsomewaytoreturnjusttheanswerwanted.Often,datafrommultipletablesarecombinedintoone,bydoingajoin.Thereareanumberofrelationaloperationsinadditiontojoin.NewWordscomputingn.计算，处理queryn.查询propertyn.性能，功能，特性；参数originatevi.起源，发生ledgern.分类帐，分户总帐receiptn.收据，收条modeln.样式，模型laymann.外行terminologyn.术语，专门名词hierarchicaladj分等级的unambiguousadj不含糊的，明确的communityn.社区，团体，社团，大众，公众dealvi处理concurrencyn.并发性failuren.故障increasinglyadv越来越多地，逐渐增加地，日益地significantadj有意义的，重大的，重要的indexn.索引，指数upwardadj.向上的linkn&v.链接nestingn.嵌接attributen.属性，特征tuplen.元组enumeratev.列举instancen.实例adheren.遵守rulen.规则qualifyvt.具有资格，证明合格；限制，限定principlen.法则，原则，原理enforcevt.执行，坚持，强迫explicitlyadv明白地，明确地cardinalityn.基数性，基数，集的势keyn.键joinv&n.连接，联结combinev.联合，结合，组合matchn&v.匹配compoundadj复合的dialectn.行话，方言generatingn.生成，发生，产生filtervt.过滤n.筛选PhrasesInanswerto回答，响应computingdiscipline计算学科Industrialrevolution工业革命relationalmodel关系模型Hierarchicalmodel层级模型beindependentof与……无关，不依赖，不受……..限制querylanguage查询语言Primarykey主键adhereto遵守Exercises[Ex.1]根据课文内容回答问题Whatcanadatabasebedefinedasincomputing?Whatisadatabasemanagementsystem(DBMS)?Wheredidthetermdatabaseoriginate?Whatisaschema?Whatdoesitdo?Whatmodelisinmostcommonusetoday?Underwhatconditiondomanyprofessionalsconsideradatabase?Listtheexamples.IsagreatdealoftheinternalengineeringofaDBMSindependentofthedatamodel?Whatisitconcernedwith?Whatdoestheflat(ortable)modelconsistsof?Howisdataorganizedinahierarchicalmodel?Whatarethethreekeytermsusedextensivelyinrelationaldatabasemodels?Howdousers(orprograms)requestdatafromarelationaldatabase?[Ex.2]根据下面的英文解释，写出相应的英文词汇(1)_____________:Asequenceofinstructionsthatrepeatseitheraspecifiednumberoftimesofuntilaparticularconditionprevails.(2)_____________:Theprocessofexatractingdatafromadatabaseandpresentingitforuse.(3)_____________:Acharacteristicattributepossessedbyallmembersofaclass.(4)_____________:Amathematicalorgraphicalrepresentationofareal-worldsituationorobject.(5)_____________:Theinabilityofacomputersystemorrelateddevicetooperatereliablyoroperateatall.(6)_____________:Alistingofkeywordsandassociateddatathatpointtolocationofmorecomprehensiveinformation,suchasfilesandrecordsonadiskorrecordkeysinadatabase.(7)_____________:Anidentifyingtermattachedtoanelementinasystemtofacilitateconnectiontootheridentifiedelements.(8)_____________:Inadatabaserecord,thenameorstructureofafield.(9)_____________:Apatternormaskthroughwhichdataispassedtoweedoutspecifieditems.[6]Yet,inordertoenforceexplicitintegrityconstraints,relationshipsbetweenrecordsintablescanalsobedefinedexplicitly,byidentifyingornon-identiringparent-childrelationshipscharacterizedbyassigningcardingality(1:1.(0)1:M,M:M).本句中，inordertoenforceexplicitintegrityconstraints作目的状语，byidentifyingornon–identifyingparent-childrelationshipscharacterizedbyassigningcardinality(1:1.(0)1:M,M:M)作方式状语。在该方式状语中，characterizedbyassigningcardinality(1:1.(0)1:M,M:M)是一个过去分词短语，作定语，修饰和限定parent-childrelationships。第三讲CLanguage第一部分课程安排一、教学目的：掌握新的专业词汇及短语。二、教学要求：能够结合专业知识理解课文内容，独立完成课后习题。三、教学重点：1、新词汇及短语的理解与记忆；2、课文的理解四、教学难点：五、教学方式：采用教师与学生互动的方式，提问问题，鼓励学生积极思考六、授课内容和课时安排：第一章信息系统建设导论第一节信息系统规划的目标和工作内容第二节信息系统规划各阶段的工作内容第三节业务流程的识别与改革七、课后练习：八、作业安排：九、本讲小结：十、课后纪要：第二部分授课内容CLanguagewhatisC?Cisacomputerprogramminglanguage.ItmeansthatyoucanuseCtocreatelistofinstructionsforacomputertofollow.Cisoneofthousandsofprogramminglanguagescurrentlyinuse.Chasbeenaroundforseveraldecadesandhaswonwidespreadacceptancebecauseitgivesprogrammersmaximumcontrolandefficiency.Cisaneasylanguagetolearn.Itisabitmorecrypticinitsstylethansomeotherlanguages,butyougetbeyondthatfairlyquickly.Ciswhatiscalledcompiledlanguage.ItmeansthatonceyouwroteyourCprogram,youmustrunitthroughaCcompilertoturnyourprogramintoanexecutablethatthecomputercanrun.TheCprogramisahuman—readableform,whiletheexecutablethatcomesoutofcompileristhemachine—readableandexecutableform.WhatthismeansisthattowriteandrunaCprogram,youmusthaveaccesstoacompiler.Ifyouareusing