chap03 Systems Development

《chap03 Systems Development》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、Chapter3SystemsDevelopment1LearningObjectivesUnderstandthatthesystemsdevelopmentlifecycle(SDLC)isamethodology–arecommendedwaytodevelopsystems.BefamiliarwiththemainSDLCapproaches–thetraditionalwaterfallcycle,prototyping,rapidapplicationdevelopment,phaseddevelopment,andbusinesspro

2、cessredesign.2LearningObjectives(Cont’d)Knowthebasicsofmodelingprocesseswithdataflowdiagramsandusecases.Understandhowsystemsdevelopmentprojectsaremanagedinatop-downfashion.Befamiliarwiththebasicprocessesofestimatingprojectcost.3SystemsDevelopmentLifeCycleMethodologyisarecommende

3、dwayofdoingsomething.Systemsdevelopmentlifecycle(SDLC)isanapplicationofthesystemsapproachtothedevelopmentofaninformationsystem.4SystemsDevelopmentLifeCycleTraditionalSDLCstagesare:PlanningAnalysisDesignImplementationUse.OftencalledwaterfallapproachTheCircularPatternoftheSDLC5The

4、SystemDevelopmentLifeCycle(SDLC)WhoparticipatesISpersonnelUserInformationspecialistscanconsultTraditionalInformationspecialistsworkingwithusers.Anewstrategy:Outsourcing6LifeCycleManagementExecutiveresponsibilityMISsteeringcommitteeFunctionsSetpolicyControlthepursestringsResolvec

5、onflicts7ExecutivesMISSteeringCommitteeProjectleader-WarehouselocationmodelteamProjectleaderMRPIIteamProjectleaderISDNsystemteamProjectleaderHRISteamMarketingManufacturingFinanceHumanResourcesProjectleaderCreditapprovalsystemteamManagersofSystemsLifeCyclesareArrangedinaHierarchy

6、8MainAdvantagesoftheSteeringCommitteeTotalfirmsupportProjectswillbecharacterizedbygoodplanningandcontrolEstablishespolicies,providesfiscalcontrol,andresolvesconflictsSincethesteeringcommitteewillprobablynotgetinvolvedwiththedetailsofthework,aprojectteamisusuallyappointed.9生命周期人

7、的生命周期：出生－成长－死亡（婴儿期、儿童期、少年期、青年期、中年期、老年期）概括地说，软件生命周期由软件定义、软件开发和运行维护三个时期组成，每个时期又可进一步划分成若干个阶段。软件定义时期（3个阶段）：问题定义、可行性研究、需求分析软件开发时期（4个阶段）：概要设计、详细设计、编码和单元测试、综合测试运行维护时期：10生命周期各个阶段的基本任务（I）软件定义时期（系统分析）问题定义：这个阶段必须回答的关键问题是：“要解决的问题是什么”。可行性研究：这个阶段要回答的关键问题是：“上一个阶段所确定的问题是否有行得通的解决办法”。需求分析：这个阶段的任务

8、仍然不是具体地解决客户的问题，而是准确地回答“目标系统必须做什么”这个问题。它的另外一项重要任