SearchHOMETECHNOLOGY MOTIVATIONARTICLEDifferent Approaches to Development ofMISCategory: System Development ApproachesThere are two basic approaches for development of MIS :a) System development life cycle : The system development life cycle havefollowing steps of development :i) Systems Planningii) Systems Analysisiii) Systems Designiv) Systems Implementationv) Systems Operation and Support (System Maintenance)
b) Prototyping : Prototyping is the process of creating an incomplete model of thefuture full-featured system, which can be used to let the users have a first idea of thecompleted program or allow the clients to evaluate the program.Advantages :i) The designer and implementer can obtain feedback from the users early in the projectdevelopment.ii) The client and the contractor can compare that the developing system matches withthe system specification, according to which the system is built.iii) It also gives the engineer some idea about the accuracy of initial project estimatesand whether the deadlines can be successfully met.The process of prototyping involves the following steps :i) Identify basic requirements.ii) Develop initial prototype.iii) Review : The customers, including end-users, examine the prototype and providefeedback for additions or changes.iv) Revise and Enhance the Prototype : Using the feedback both the specificationsand the prototype can be improved. If changes are introduced then a repetition of steps3 and 4 may be needed.Types of prototyping : System prototyping are of various kinds. However, all themethods are in some way based on two major types of prototyping :
Throwaway Prototyping : Throwaway or Rapid Prototyping refers to the creationof a model that will eventually be discarded rather than becoming part of the finallydelivered system. After preliminary requirements gathering is accomplished, a simpleworking model of the system is constructed to visually show the users what theirrequirements may look like when they are implemented into a finished system. Themost obvious reason for using Throwaway Prototyping is that it can be done quickly.Evolutionary Prototyping : Evolutionary Prototyping (also knownas Breadboard Prototyping) is quite different from Throwaway Prototyping. Themain goal when usingEvolutionary Prototyping is to build a very good prototype in a structured manner sothat we can refine it or make further changes to it. The reason for this is that theEvolutionary prototype, when built, forms the heart of the new system, and theimprovements and further requirements will be built on to it. It is not discarded orremoved like the Throwaway Prototype. When developing a system using EvolutionaryPrototyping, the system is continually refined and rebuilt.Incremental Prototyping : The final product is built as separate prototypes. At theend the separate prototypes are merged in an overall design.Advantages of Prototyping :i) Reduced Time and Costs : Prototyping can improve the quality ofrequirements and specifications provided to developers. Early determination of whatthe user really wants can result in faster and less expensive software.ii) Improved and Increased User Involvement : Prototyping requires userinvolvement and allows them to see and interact with a prototype; allowing them toprovide better and more complete feedback and specifications. Since users know the
problem better than anyone, the final product is more likely to satisfy the users desirefor look, feel and performance.Disadvantages of Prototyping :i) Insufficient Analysis : Since a model has to be created, developers will notproperly analyse the complete project. This may lead to a poor prototype and a finalproject that will not satisfy the users.ii) User Confusion of Prototype and Finished System : Users can begin to thinkthat a prototype, intended to be thrown away, is actually a final system that merelyneeds to be finished or polished. Users can also become attached to features that wereincluded in a prototype for consideration and then removed from the specification for afinal system.iii) Excessive Development Time of the Prototype : A key property to prototypingis the fact that it is supposed to be done quickly. If the developers forget about this fact,they will develop a prototype that is too complex.iv) Expense of Implementing Prototyping : The start up costs for building adevelopment team focused on prototyping may be high. Many companies have to trainthe team for this purpose which needs extra expenses.Different Approaches To Development Of MISDifferent System Development Stages? Explain In DetailWaterfall ModelWhat Are The Different Stages Of System Investigation? ExplainStages Of Development Of MISWhat Are The Different System Development Stages? DiscussEach Of Them Briefly
Computer FundamentalComputer NetworkingStructured Query (SQL)Java ScriptHTML LanguageCascading Style SheetC Programming (Theory)C Programming (Pratical)Visual BasicC++ ProgrammingJava ProgrammingComputer GraphicsElectronic CommerceManagement (MIS)o Information Systemo What is MISo Structure & Classificationo System Designo Decision Makingo System Conceptso System Approacheso System Analysiso Imp & Evaluationo Information EnablerData StructuresSoftware EngineeringDigital ElectronicsC# ProgrammingDatabase SystemConnect Us On FaceBook |Dinesh Thakur is a Technology Columinist and founderof Computer Notes and Technology Motivation.Computer Notes
Management informationsystemFrom Wikipedia, the free encyclopediaThis article has multiple issues. Pleasehelp improve it or discuss these issues onthe talk page.This articles tone or style may not reflectthe encyclopedic tone used onWikipedia. (November 2012)This article needs additional citations forverification. (November 2012)A management information system (MIS) providesinformation that organizations need to manage themselvesefficiently and effectively.Management informationsystems are typically computer systems used for managingfive primary components: hardware, software,data(information for decision making), procedures(design,development and documentation), people (individuals,groups, or organizations),. Management information systemsare distinct from other information systems, in that they areused to analyze and facilitate strategic and operationalactivities.Academically, the term is commonly used to referto the study of how individuals, groups, and organizationsevaluate, design, implement, manage, and utilize systems to
generate information to improve efficiency and effectivenessof decision making, including systems termed decisionsupport systems, expert systems, and executive informationsystems.Most business schools (or colleges of businessadministration within universities) have an MIS department,alongside departments of accounting, finance, management,marketing, and sometimes others, and grant degrees (atundergrad, masters, and PhD levels) in MIS.Contents[hide]1 Overview2 History3 Types and Terminology4 Advantages5 Enterprise applications6 Developing Information Systems7 See also8 References9 External linksOverviewThis section doesnot cite any references orsources. Please help improve thissection by adding citations to reliablesources. Unsourced material may bechallenged and removed. (November
2012)This section may contain originalresearch. Please improveit by verifying the claims made andadding inline citations. Statementsconsisting only of original research maybe removed. (November 2012)A management information system gives the businessmanagers the information that they need to make decisions.Early business computers were used for simple operationssuch as tracking inventory, billing, sales, or payroll data, withlittle detail or structure.Over time, these computerapplications became more complex, hardware storagecapacities grew, and technologies improved for connectingpreviously isolated applications. As more data was stored andlinked, managers sought greater abstraction as well asgreater detail with the aim of creating significant managementreports from the raw, stored data. Originally, the term "MIS"described applications providing managers with informationabout sales, inventories, and other data that would help inmanaging the enterprise. Over time, the term broadened toinclude: decision support systems, resourcemanagement and human resource management, enterpriseresource planning (ERP),enterprise performancemanagement (EPM), supply chainmanagement (SCM), customer relationshipmanagement (CRM), project management and databaseretrieval applications.
HistoryKenneth and Jane Laudon identify five eras of MIS evolutioncorresponding to the five phases in the developmentof computing technology: 1) mainframe and minicomputercomputing, 2) personal computers, 3) client/server networks,4) enterprise computing, and 5) cloud computing.The first era (mainframe and minicomputer) was ruled by IBMand their mainframe computers; these computers would oftentake up whole rooms and require teams to run them - IBMsupplied the hardware and the software. As technologyadvanced, these computers were able to handle greatercapacities and therefore reduce their cost. Smaller, moreaffordable minicomputers allowed larger businesses to runtheir own computing centers in-house.The second era (personal computer) began in 1965 asmicroprocessors started to compete with mainframes andminicomputers and accelerated the process of decentralizingcomputing power from large data centers to smaller offices. Inthe late 1970s minicomputer technology gave way to personalcomputers and relatively low cost computers were becomingmass market commodities, allowing businesses to providetheir employees access to computing power that ten yearsbefore would have cost tens of thousands of dollars. Thisproliferation of computers created a ready market forinterconnecting networks and the popularization of theInternet.As technological complexity increased and costs decreased,the need to share information within an enterprise also grew—giving rise to the third era (client/server), in which computerson a common network access shared information on a server.This lets thousands and even millions of people access data
simultaneously. The fourth era (enterprise) enabled by highspeed networks, tied all aspects of the business enterprisetogether offering rich information access encompassing thecomplete management structure.The fifth era (cloud computing) is the latest and employsnetworking technology to deliver applications as well as datastorage independent of the configuration, location or nature ofthe hardware. This, along with highspeed cellphone and wifi networks, led to new levels ofmobility in which managers access the MIS remotely withlaptops, tablet PCs, and smartphones.Types and TerminologyThe terms Management InformationSystem (MIS), information system, Enterprise ResourcePlanning (ERP), and information technology management areoften confused. Information systems and MIS are broadercategories that include ERP. Informationtechnology management concerns the operation andorganization of information technology resources independentof their purpose.Most management information systems specialize inparticular commercial and industrial sectors, aspects of theenterprise, or management substructure.Management information systems (MIS), produce fixed,regularly scheduled reports based on data extracted andsummarized from the firm’s underlying transactionprocessing systemsto middle and operational levelmanagers to identify and inform structured and semi-structured decision problems.
Decision Support Systems (DSS) are computer programapplications used by middle management to compileinformation from a wide range of sources to supportproblem solving and decision making.Executive Information Systems (EIS) is a reporting tool thatprovides quick access to summarized reports coming fromall company levels and departments such as accounting,human resources and operations.Marketing Information Systems (MIS) are ManagementInformation Systems designed specifically for managingthe marketing aspects of the business.Office Automation Systems (OAS) support communicationand productivity in the enterprise by automating work flowand eliminating bottlenecks. OAS may be implemented atany and all levels of management.School Information Management Systems (SIMS) coverschool administration,and often including teaching andlearning materials.Enterprise Resource Planning (ERP) facilitates the flow ofinformation between all business functions inside theboundaries of the organization and manage theconnections to outside stakeholders.AdvantagesThe following are some of the benefits that can be attained fordifferent types of management information systems.Companies are able to highlight their strengths andweaknesses due to the presence of revenue reports,employees performance record etc. The identification ofthese aspects can help the company improve theirbusiness processes and operations.
Giving an overall picture of the company and acting as acommunication and planning tool.The availability of the customer data and feedback can helpthe company to align their business processes according tothe needs of the customers. The effective management ofcustomer data can help the company to perform directmarketing and promotion activities.Enterprise applicationsEnterprise systems—also known as enterprise resourceplanning (ERP) systems—provide integrated softwaremodules and a unified database that personnel use to plan,manage, and control core business processes acrossmultiple locations. Modules of ERP systems may includefinance, accounting, marketing, human resources,production, inventory management, and distribution.Supply chain management (SCM) systems enable moreefficient management of the supply chain by integrating thelinks in a supply chain. This may include suppliers,manufacturers, wholesalers, retailers, and final customers.Customer relationship management (CRM) systems helpbusinesses manage relationships with potential and currentcustomers and business partners across marketing, sales,and service.Knowledge management system (KMS) helpsorganizations facilitate the collection, recording,organization, retrieval, and dissemination of knowledge.This may include documents, accounting records,unrecorded procedures, practices, and skills.
Developing Information Systems"The actions that are taken to create an information systemthat solves an organizational problem are called systemdevelopment".These include system analysis, systemdesign, computer programming/implementation, testing,conversion, production and finally maintenance. Theseactions usually take place in that specified order but somemay need to repeat or be accomplished concurrently.Conversion is the process of changing or converting the oldsystem into the new. This can be done in three basic ways,though newer methods (prototyping, Extreme Programming,JAD, etc.) are replacing these traditional conversion methodsin many cases:Direct cut – The new system replaces the old at anappointed time.Pilot study -– Introducing the new system to a small portionof the operation to see how it fares. If good then the newsystem expands to the rest of the company.Phased approach – New system is introduced in stages.See alsoEnterprise Information SystemBachelor of Computer Information SystemsBusiness intelligenceBusiness performance managementBusiness ruleCorporate governance of information technologyData miningPredictive analytics
Purchase order requestEnterprise architectureEnterprise planning systemManagement by objectivesOnline analytical processingOnline office suiteReal-time MarketingReferences1. ^ http://www.occ.gov/publications/publications-by-type/comptrollers-handbook/mis.pdf2. ^ a bO’Brien, J (1999). Management Information Systems –Managing Information Technology in the InternetworkedEnterprise. Boston: Irwin McGraw-Hill. ISBN 0-07-112373-3.3. ^ Lucey, Terry (2005). Management Information Systems.London: Thomson. p. 336. ISBN 978-1-84480-126-8.4. ^ Laudon, Kenneth C.; Laudon, Jane P. (2009).ManagementInformation Systems: Managing the Digital Firm (11 ed.).Prentice Hall/CourseSmart. p. 164.5. ^ Transaction processing systems (TPS) collect and recordthe routine transactions of an organization. Examples of suchsystems are sales order entry, hotel reservations, payroll,employee record keeping, and shipping.6. ^ Bidgoli, Hossein, (2004). The Internet Encyclopedia, Volume1, John Wiley & Sons, Inc. p. 707.7. ^ Pant, S., Hsu, C., (1995), Strategic Information SystemsPlanning: A Review, Information Resources ManagementAssociation International Conference, May 21–24, Atlanta.8. ^ Laudon, K.,&Laudon, J. (2010). Management informationsystems: Managing the digital firm. (11th ed.). Upper SaddleRiver, NJ: Pearson Prentice Hall.
External linksComputer and Information Systems Managers (U.S.Department of Labor)Index of Information Systems JournalsMIS Web sites (Bournemouth University)MIS Links (University of York)Executive Information Systems: Minimising the risk ofdevelopmentCategories:Business softwareDecision theoryInformation systemsInformation technology managementManagement systemsNavigation menuCreate accountLog inArticleTalkReadEditView historyMain pageContentsFeatured contentCurrent eventsRandom article
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Systems development life-cycleFrom Wikipedia, the free encyclopediaFor other uses, see SDLC (disambiguation).Model of the Systems Development Life CycleThe systems development life cycle (SDLC), or softwaredevelopment process in systems engineering, informationsystems and software engineering, is a process of creating oraltering information systems, and the modelsand methodologies that people use to develop these systems.In software engineering, the SDLC concept underpins manykinds of software development methodologies. Thesemethodologies form the framework for planning andcontrolling the creation of an informationsystem:the software development process.
Contents[hide]1 Overview2 History3 Systems development phaseso 3.1 System analysiso 3.2 Designo 3.3 Testingo 3.4 Operations and maintenanceo 3.5 Evolution4 Systems analysis and design5 Object-oriented analysis6 Systems development life cycleo 6.1 Management and controlo 6.2 Work breakdown structured organizationo 6.3 Baselines in the SDLCo 6.4 Complementary to SDLC7 Strengths and weaknesses8 See also9 References10 Further reading11 External linksOverviewThe Systems development life cycle (SDLC) is a processused by a systems analyst to develop an information system,training, and user (stakeholder) ownership. The SDLC aims toproduce a high quality system that meets or exceedscustomer expectations, reaches completion within time andcost estimates, works effectively and efficiently in the current
and planned Information Technology infrastructure, and isinexpensive to maintain and cost-effective to enhance.Computer systems are complex and often (especially with therecent rise of service-oriented architecture) link multipletraditional systems potentially supplied by different softwarevendors. To manage this level of complexity, a number ofSDLC models or methodologies have been created, such as"waterfall"; "spiral"; "Agile software development"; "rapidprototyping"; "incremental"; and "synchronize and stabilize".SDLC can be described along spectrum of agile to iterative tosequential. Agile methodologies, such as XP and Scrum,focus on lightweight processes which allow for rapid changesalong the development cycle. Iterative methodologies, suchas Rational Unified Process and dynamic systemsdevelopment method, focus on limited project scope andexpanding or improving products by multiple iterations.Sequential or big-design-up-front (BDUF) models, suchas Waterfall, focus on complete and correct planning to guidelarge projects and risks to successful and predictableresults. Other models, such as AnamorphicDevelopment, tend to focus on a form of development that isguided by project scope and adaptive iterations of featuredevelopment.In project management a project can be defined both witha project life cycle (PLC) and an SDLC, during which slightlydifferent activities occur. According to Taylor (2004) "theproject life cycle encompasses all the activities of the project,while the systems development life cycle focuses on realizingthe product requirements".SDLC (systems development lifecycle) is used during the development of an IT project, itdescribes the different stages involved in the project from the
drawing board, through the completion of the project. SDLC issoftware developmentHistoryThe systems life cycle (SLC) is a methodology used todescribe the process for building information systems,intended to develop information systems in a very deliberate,structured and methodical way, reiterating each stage ofthe life cycle. The systems development life cycle, accordingto Elliott & Strachan & Radford (2004), "originated in the1960s, to develop large scale functional business systems inan age of large scale business conglomerates. Informationsystems activities revolved around heavy dataprocessing and number crunching routines".Several systems development frameworks have been partlybased on SDLC, such as the structured systems analysis anddesign method (SSADM) produced for the UKgovernment Office of Government Commerce in the 1980s.Ever since, according to Elliott (2004), "the traditional lifecycle approaches to systems development have beenincreasingly replaced with alternative approaches andframeworks, which attempted to overcome some of theinherent deficiencies of the traditional SDLC".Systems development phasesThis section needs additional citationsfor verification. Please help improvethis article by adding citations toreliable sources. Unsourced materialmay
be challenged and removed. (September2010)The System Development Life Cycle framework provides asequence of activities for system designers and developers tofollow. It consists of a set of steps or phases in which eachphase of the SDLC uses the results of the previous one.A Systems Development Life Cycle (SDLC) adheres toimportant phases that are essential for developers, suchas planning, analysis, design, and implementation, and areexplained in the section below.It include evaluation of presentsystem, information gathering, feasibility study and requestapproval. A number of system development life cycle (SDLC)models have been created: waterfall, fountain, spiral, buildand fix, rapid prototyping, incremental, and synchronize andstabilize. The oldest of these, and the best known, isthe waterfall model: a sequence of stages in which the outputof each stage becomes the input for the next. These stagescan be characterized and divided up in different ways,including the following:Preliminary Analysis: The objective of phase 1 is toconduct a preliminary analysis, propose alternativesolutions, describe costs and benefits and submit apreliminary plan with recommendations.Conduct the preliminary analysis: in this step, you needto find out the organizations objectives and the natureand scope of the problem under study. Even if a problemrefers only to a small segment of the organization itselfthen you need to find out what the objectives of theorganization itself are. Then you need to see how theproblem being studied fits in with them.
Propose alternative solutions: In digging into theorganizations objectives and specific problems, you mayhave already covered some solutions. Alternateproposals may come from interviewing employees,clients , suppliers, and/or consultants. You can also studywhat competitors are doing. With this data, you will havethree choices: leave the system as is, improve it, ordevelop a new system.Describe the costs and benefits.Systems analysis, requirements definition:Defines project goals into defined functions andoperation of the intended application. Analyzesend-user information needs.Systems design: Describes desired features andoperations in detail, including screen layouts,business rules, process diagrams, pseudocode andother documentation.Development: The real code is written here.Integration and testing: Brings all the piecestogether into a special testing environment, thenchecks for errors, bugs and interoperability.Acceptance, installation, deployment: The finalstage of initial development, where the software isput into production and runs actual business.Maintenance: What happens during the rest of thesoftwares life: changes, correction, additions,moves to a different computing platform and more.This is often the longest of the stages.
In the following example (see picture) these stage ofthe systems development life cycle are divided in tensteps from definition to creation and modification of ITwork products:The tenth phase occurs when the system is disposed of and thetask performed is either eliminated or transferred to othersystems. The tasks and work products for each phase aredescribed in subsequent chapters.Not every project will require that the phases besequentially executed. However, the phases areinterdependent. Depending upon the size andcomplexity of the project, phases may be combined ormay overlap.
System analysisThe goal of system analysis is to determine where theproblem is in an attempt to fix the system.This stepinvolves breaking down the system in different piecesto analyze the situation, analyzing project goals,breaking down what needs to be created andattempting to engage users so that definiterequirements can be defined.DesignIn systems design the design functions and operationsare described in detail, including screen layouts,business rules, process diagrams and otherdocumentation. The output of this stage will describethe new system as a collection of modules orsubsystems.The design stage takes as its initial input therequirements identified in the approved requirementsdocument. For each requirement, a set of one or moredesign elements will be produced as a result ofinterviews, workshops, and/or prototype efforts.Design elements describe the desired softwarefeatures in detail, and generally include functionalhierarchy diagrams, screen layout diagrams, tables ofbusiness rules, business process diagrams, pseudo-code, and a complete entity-relationship diagram witha full data dictionary. These design elements areintended to describe the software in sufficient detailthat skilled programmers may develop the softwarewith minimal additional input design.Testing
The code is tested at various levels in softwaretesting. Unit, system and user acceptance testings areoften performed. This is a grey area as many differentopinions exist as to what the stages of testing are andhow much, if any iteration occurs. Iteration is notgenerally part of the waterfall model, but usually someoccur at this stage. In the testing the whole system istest one by oneFollowing are the types of testing:Defect testing the failed scenarios, including defecttrackingPath testingData set testingUnit testingSystem testingIntegration testingBlack-box testingWhite-box testingRegression testingAutomation testingUser acceptance testingSoftware performance testingOperations and maintenanceThe deployment of the system includes changes andenhancements before the decommissioning or sunsetof the system. Maintaining the system is an importantaspect of SDLC. As key personnel change positions inthe organization, new changes will be implemented.There are two approaches to System Development,there are traditional approach (structured) and Object
Oriented. Information Engineering includes traditionalsystem approach or it also called as StructuredAnalysis and Design Technique. Object Orientedapproach views information system as the collectionof objects that integrated each others to make a fullcomplete information system.EvolutionThis section is empty. You can helpby adding to it. (April 2013)The final phase of the SDLC is to measure theeffectiveness of the application and evaluate potentialenhancements....Systems analysis and designThe Systems Analysis and Design (SAD) is theprocess of developing Information Systems (IS) thateffectively use hardware, software, data, processes,and people to support the companys businessesobjectives. System Analysis and Design can beconsidered the meta-development activity, whichserves to set the stage and bound the problem. SADcan be leveraged to set the correct balance amongcompeting high-level requirements in the functionaland non-functional analysis domains. System Analysisand Design interacts strongly with distributedEnterprise Architecture, Enterprise I.T. Architecture,and Business Architecture, and relies heavily onconcepts such as partitioning, interfaces, personaeand roles, and deployment/operational modeling toarrive at a high-level system description. This highlevel description is then further broken down into the
components and modules which can be analyzed,designed, and constructed separately and integratedto accomplish the business goal. SDLC and SAD arecornerstones of full-lifecycle product and systemplanning.Object-oriented analysisObject-oriented analysis (OOA) is the process ofanalyzing a task (also known as a problem domain), todevelop a conceptual model that can then be used tocomplete the task. A typical OOA model woulddescribe computer software that could be used tosatisfy a set of customer-defined requirements. Duringthe analysis phase of problem-solving, a programmermight consider a written requirements statement, aformal vision document, or interviews withstakeholders or other interested parties. The task tobe addressed might be divided into several subtasks(or domains), each representing a different business,technological, or other areas of interest. Each subtaskwould be analyzed separately. Implementationconstraints,(e.g., concurrency, distribution,persistence, or how thesystem is to be built) are not considered during theanalysis phase; rather, they are addressed duringobject-oriented design (OOD).The conceptual model that results from OOA willtypically consist of a set of use cases, one ormore UML class diagrams, and a numberof interaction diagrams. It may also include some kindofuser interface mock-up.
The input for object-oriented design is provided by theoutput of object-oriented analysis. Realize that anoutput artifact does not need to be completelydeveloped to serve as input of object-oriented design;analysis and design may occur in parallel, and inpractice the results of one activity can feed the otherin a short feedback cycle through an iterative process.Both analysis and design can be performedincrementally, and the artifacts can be continuouslygrown instead of completely developed in one shot.Some typical input artifacts for object-oriented designare:Conceptual model: Conceptual model is the resultof object-oriented analysis, it captures concepts inthe problem domain. The conceptual model isexplicitly chosen to be independent ofimplementation details, such as concurrency ordata storage.Use case: Use case is a description of sequencesof events that, taken together, lead to a systemdoing something useful. Each use case providesone or more scenarios that convey how the systemshould interact with the users called actors toachieve a specific business goal or function. Usecase actors may be end users or other systems. Inmany circumstances use cases are furtherelaborated into use case diagrams. Use casediagrams are used to identify the actor (users orother systems) and the processes they perform.
System Sequence Diagram: System Sequencediagram (SSD) is a picture that shows, for aparticular scenario of a use case, the events thatexternal actors generate, their order, and possibleinter-system events.User interface documentations (if applicable):Document that shows and describes the look andfeel of the end products user interface. It is notmandatory to have this, but it helps to visualize theend-product and therefore helps the designer.Relational data model (if applicable): A data modelis an abstract model that describes how data isrepresented and used. If an object database is notused, the relational data model should usually becreated before the design, since the strategychosen for object-relational mapping is an output ofthe OO design process. However, it is possible todevelop the relational data model and the object-oriented design artifacts in parallel, and the growthof an artifact can stimulate the refinement of otherartifacts.Systems development life cycleManagement and control
SPIU phases related to management controls.The SDLC phases serve as a programmatic guide toproject activity and provide a flexible but consistentway to conduct projects to a depth matching the scopeof the project. Each of the SDLC phase objectives aredescribed in this section with key deliverables, adescription of recommended tasks, and a summary ofrelated control objectives for effective management. Itis critical for the project manager to establish andmonitor control objectives during each SDLC phasewhile executing projects. Control objectives help toprovide a clear statement of the desired result orpurpose and should be used throughout the entireSDLC process. Control objectives can be grouped intomajor categories (domains), and relate to the SDLCphases as shown in the figure.To manage and control any SDLC initiative, eachproject will be required to establish some degree ofa Work Breakdown Structure (WBS) to capture and
schedule the work necessary to complete the project.The WBS and all programmatic material should bekept in the "project description" section of the projectnotebook. The WBS format is mostly left to the projectmanager to establish in a way that best describes theproject work.There are some key areas that must be defined in theWBS as part of the SDLC policy. The followingdiagram describes three key areas that will beaddressed in the WBS in a manner established by theproject manager.Work breakdown structuredorganizationWork breakdown structure.The upper section of the work breakdownstructure (WBS) should identify the major phases andmilestones of the project in a summary fashion. Inaddition, the upper section should provide an overviewof the full scope and timeline of the project and will bepart of the initial project description effort leading toproject approval. The middle section of the WBS isbased on the seven systems development life cycle
(SDLC) phases as a guide for WBS task development.The WBS elements should consist of milestones and"tasks" as opposed to "activities" and have a definitiveperiod (usually two weeks or more). Each task musthave a measurable output (e.x. document, decision, oranalysis). A WBS task may rely on one or moreactivities (e.g. software engineering, systemsengineering) and may require close coordination withother tasks, either internal or external to the project.Any part of the project needing support fromcontractors should have a statement of work (SOW)written to include the appropriate tasks from the SDLCphases. The development of a SOW does not occurduring a specific phase of SDLC but is developed toinclude the work from the SDLC process that may beconducted by external resources such as contractorsand struct.Baselines in the SDLCBaselines are an important part of the systemsdevelopment life cycle (SDLC). These baselines areestablished after four of the five phases of the SDLCand are critical to the iterative nature of the model.Each baseline is considered as a milestone in theSDLC.functional baseline: established after the conceptualdesign phase.allocated baseline: established after the preliminarydesign phase.product baseline: established after the detail designand development phase.
updated product baseline: established after theproduction construction phase.Complementary to SDLCComplementary software development methods tosystems development life cycle (SDLC) are:Software prototypingJoint applications development (JAD)Rapid application development (RAD)Extreme programming (XP); extension of earlierwork in Prototyping and RAD.Open-source developmentEnd-user developmentObject-oriented programmingComparison of Methodology Approaches (Post, &Anderson 2006)SDLC RADOpensourceObjectsJADPrototypingEndUserControl Formal MIS WeakStandardsJoint UserUserTimeframeLongShortMediumAnyMediumShortShort–Users Many Few Few Varies Few One or One
twoMIS staff Many FewHundredsSplit FewOne ortwoNoneTransaction/DSSTransactionBoth Both Both DSS DSS DSSInterfaceMinimalMinimalWeakWindowsCrucialCrucialCrucialDocumentation andtrainingVitalLimitedInternalInObjectsLimitedWeakNoneIntegrityandsecurityVital VitalUnknownInObjectsLimitedWeakWeakReusabilityLimitedSomeMaybeVitalLimitedWeakNoneStrengths and weaknessesFew people in the modern computing world would usea strict waterfall model for their systems developmentlife cycle (SDLC) as many modern methodologieshave superseded this thinking. Some will argue thatthe SDLC no longer applies to models like Agilecomputing, but it is still a term widely in use in
technology circles. The SDLC practice hasadvantages in traditional models of softwaredevelopment, that lends itself more to a structuredenvironment. The disadvantages to using the SDLCmethodology is when there is need for iterativedevelopment or (i.e. web development or e-commerce) where stakeholders need to review on aregular basis the software being designed. Instead ofviewing SDLC from a strength or weaknessperspective, it is far more important to take the bestpractices from the SDLC model and apply it towhatever may be most appropriate for the softwarebeing designed.A comparison of the strengths and weaknesses ofSDLC:Strength and Weaknesses of SDLC Strengths WeaknessesControl. Increased development time.Monitor large projects. Increased development cost.Detailed steps.Systems must be defined upfront.Evaluate costs andcompletion targets.Rigidity.Documentation. Hard to estimate costs,
project overruns.Well defined user input.User input is sometimeslimited.Ease of maintenance.Development and designstandards.Tolerates changes in MISstaffing.An alternative to the SDLC is rapid applicationdevelopment, which combines prototyping, jointapplication development and implementation of CASEtools. The advantages of RAD are speed, reduceddevelopment cost, and active user involvement in thedevelopment process.See alsoApplication lifecycle managementReferences1. ^ SELECTING A DEVELOPMENT APPROACH.Retrieved 27 October 2008.2. ^ "Systems Development Life Cycle".In: Foldoc(2000-12-24)3. ^ Software Development Life Cycle (SDLC), PowerPoint, – Powered by Google Docs
4. ^ James Taylor (2004). Managing InformationTechnology Projects. p.39..5. ^ a bGeoffrey Elliott & Josh Strachan (2004) GlobalBusiness Information Technology. p.87.6. ^ QuickStudy: System Development Life Cycle, ByRussell Kay, May 14, 20027. ^ a bUS Department of Justice(2003). INFORMATION RESOURCESMANAGEMENT Chapter 1. Introduction.8. ^ a b c d eU.S. House of Representatives(1999). Systems Development Life-Cycle Policy. p.13.9. ^ Blanchard, B. S., & Fabrycky, W. J.(2006) Systemsengineering and analysis (4th ed.) New Jersey:Prentice Hall. p.3110. ^ a bPost, G., & Anderson, D., (2006). Managementinformation systems: Solving business problems withinformation technology. (4th ed.). New York: McGraw-Hill Irwin.Further readingBlanchard, B. S., & Fabrycky, W. J.(2006) Systemsengineering and analysis (4th ed.) New Jersey:Prentice Hall.Cummings, Haag (2006). Management InformationSystems for the Information Age. Toronto, McGraw-Hill RyersonBeynon-Davies P. (2009). Business InformationSystems. Palgrave, Basingstoke. ISBN 978-0-230-20368-6Computer World, 2002, Retrieved on June 22, 2006from the World Wide Web:Management Information Systems, 2005, Retrievedon June 22, 2006 from the World Wide Web:
This article is based on material taken fromthe Free On-line Dictionary of Computing prior to 1November 2008 and incorporated under the"relicensing" terms of the GFDL, version 1.3 orlater.External linksWikimedia Commons has mediarelated to: Systems DevelopmentLife CycleThe Agile System Development LifecyclePension Benefit Guaranty Corporation –Information Technology Solutions LifecycleMethodologyFSA Life Cycle FrameworkHHS Enterprise Performance Life Cycle FrameworkThe Open Systems Development Life CycleSystem Development Life Cycle Evolution ModelingZero Deviation Life CycleIntegrated Defense AT&L Life Cycle ManagementChart, the U.S. DoD form of this concept.VTESo
PrototypeFrom Wikipedia, the free encyclopediaFor other uses, see Prototype (disambiguation).A prototype is an early sample or model built to test aconcept or process or to act as a thing to be replicated orlearned from. It is a term used in a variety of contexts,including semantics,design, electronics, and softwareprogramming. A prototype is designed to test and trial a newdesign to enhance precision by system analysts and users.Prototyping serves to provide specifications for a real, workingsystem rather than a theoretical one.The word prototype derives fromthe Greek πρωτότσπον (prototypon), "primitive form", neutralof πρωτότσπος (prototypos), "original, primitive",from πρῶτος (protos), "first" and τύπος (typos),"impression".
Contents[hide]1 Semantics2 Design and modeling3 Basic prototype categories4 Differences between a prototype and a production design5 Characteristics and limitations of prototypes6 Modern trends7 Mechanical and electrical engineering8 Electronics prototyping9 Computer programming/computer science10 Software release cycle11 Data prototyping12 Scale modeling13 Metrology14 Sciences15 ReferencesSemanticsFor more details on this topic, see Prototype theory.In semantics, prototypes or proto instances combine the mostrepresentative attributes of a category. Prototypes are typicalinstances of a category that serve as benchmarks againstwhich the surrounding, less representative members areanalysed.Design and modelingIn many fields, there is great uncertainty as to whether a newdesign will actually do what is desired. New designs often
have unexpected problems. A prototype is often used as partof the product design process to allow engineers anddesigners the ability to explore design alternatives, testtheories and confirm performance prior to starting productionof a new product. Engineers use their experience to tailor theprototype according to the specific unknowns still present inthe intended design. For example, some prototypes are usedto confirm and verify consumer interest in a proposed designwhereas other prototypes will attempt to verify theperformance or suitability of a specific design approach.In general, an iterative series of prototypes will be designed,constructed and tested as the final design emerges and isprepared for production. With rare exceptions, multipleiterations of prototypes are used to progressively refine thedesign. A common strategy is to design, test, evaluate andthen modify the design based on analysis of the prototype.In many products it is common to assign the prototypeiterations Greek letters. For example, a first iteration prototypemay be called an "Alpha" prototype. Often this iteration is notexpected to perform as intended and some amount of failuresor issues are anticipated. Subsequent prototyping iterations(Beta, Gamma, etc.) will be expected to resolve issues andperform closer to the final production intent.In many product development organizations, prototypingspecialists are employed - individuals with specialized skillsand training in general fabrication techniques that can helpbridge between theoretical designs and the fabrication ofprototypes.
Basic prototype categoriesThere is no general agreement on what constitutes a"prototype" and the word is often used interchangeably withthe word "model" which can cause confusion. In general,"prototypes" fall into five basic categories:Proof-of-Principle Prototype (Model) (in electronicssometimes built on a breadboard). A Proof ofconcept prototype is used to test some aspect of the intendeddesign without attempting to exactly simulate the visualappearance, choice of materials or intended manufacturingprocess. Such prototypes can be used to "prove" out apotential design approach such as range of motion,mechanics, sensors, architecture, etc. These types of modelsare often used to identify which design options will not work,or where further development and testing is necessary.Form Study Prototype (Model). This type of prototype willallow designers to explore the basic size, look and feel of aproduct without simulating the actual function or exact visualappearance of the product. They can help assess ergonomicfactors and provide insight into visual aspects of the productsfinal form. Form Study Prototypes are often hand-carved ormachined models from easily sculpted, inexpensive materials(e.g., urethane foam), without representing the intended color,finish, or texture. Due to the materials used, these models areintended for internal decision making and are generally notdurable enough or suitable for use by representative users orconsumers.User Experience Prototype (Model). A User ExperienceModel invites active human interaction and is primarily used tosupport user focused research. While intentionally notaddressing possible aesthetic treatments, this type of model
does more accurately represent the overall size, proportions,interfaces, and articulation of a promising concept. This typeof model allows early assessment of how a potential userinteracts with various elements, motions, and actions of aconcept which define the initial use scenario and overall userexperience. As these models are fully intended to be usedand handled, more robust construction is key. Materialstypically include plywood, REN shape, RP processes andCNC machined components. Construction of user experiencemodels is typically driven by preliminary CAID/CAD whichmay be constructed from scratch or with methods suchas industrial CT scanning.Visual Prototype (Model) will capture the intended designaesthetic and simulate the appearance, color and surfacetextures of the intended product but will not actually embodythe function(s) of the final product. These models will besuitable for use in market research, executive reviews andapproval, packaging mock-ups, and photo shoots for salesliterature.Functional Prototype (Model) (also called a workingprototype) will, to the greatest extent practical, attempt tosimulate the final design, aesthetics, materials andfunctionality of the intended design. The functional prototypemay be reduced in size (scaled down) in order to reducecosts. The construction of a fully working full-scale prototypeand the ultimate test of concept, is the engineers final checkfor design flaws and allows last-minute improvements to bemade before larger production runs are ordered.
Differences between a prototype and aproduction designIn general, prototypes will differ from the final productionvariant in three fundamental ways:Materials. Production materials may require manufacturingprocesses involving higher capital costs than what is practicalfor prototyping. Instead, engineers or prototyping specialistswill attempt to substitute materials with properties thatsimulate the intended final material.Processes. Often expensive and time consuming uniquetooling is required to fabricate a custom design. Prototypeswill often compromise by using more variable processes,repeatable or controlled methods; substandard, inefficient, orsubstandard technology sources; or insufficient testing fortechnology maturity.Lower fidelity. Final production designs often requireextensive effort to capture high volume manufacturing detail.Such detail is generally unwarranted for prototypes as somerefinement to the design is to be expected. Often prototypesare built using very limited engineering detail as compared tofinal production intent, which often uses statistical processcontrols and rigorous testing.Characteristics and limitations ofprototypesEngineers and prototyping specialists seek to understand thelimitations of prototypes to exactly simulate the characteristicsof their intended design.
It is important to realize that by their very definition, prototypeswill represent some compromise from the final productiondesign. Due to differences in materials, processes and designfidelity, it is possible that a prototype may fail to performacceptably whereas the production design may have beensound. A counter-intuitive idea is that prototypes may actuallyperform acceptably whereas the production design may beflawed since prototyping materials and processes mayoccasionally outperform their production counterparts.In general, it can be expected that individual prototype costswill be substantially greater than the final production costs dueto inefficiencies in materials and processes. Prototypes arealso used to revise the design for the purposes of reducingcosts through optimization and refinement.It is possible to use prototype testing to reduce the risk that adesign may not perform as intended, however prototypesgenerally cannot eliminate all risk. There are pragmatic andpractical limitations to the ability of a prototype to match theintended final performance of the product and someallowances and engineering judgement are often requiredbefore moving forward with a production design.Building the full design is often expensive and can be time-consuming, especially when repeated several times—buildingthe full design, figuring out what the problems are and how tosolve them, then building another full design. As analternative, "rapid-prototyping" or "rapid applicationdevelopment" techniques are used for the initial prototypes,which implement part, but not all, of the complete design. Thisallows designers and manufacturers to rapidly andinexpensively test the parts of the design that are most likelyto have problems, solve those problems, and then build thefull design.
This counter-intuitive idea —that the quickest way to buildsomething is, first to build something else— is sharedby scaffolding and the telescope rule.Modern trendsWith the recent advances in computer modeling it is becomingpractical to eliminate the creation of a physical prototype(except possibly at greatly reduced scales for promotionalpurposes), instead modeling all aspects of the final product asa computer model. An example of such a development can beseen in Boeing 787 Dreamliner, in which the first full sizedphysical realization is made on the series production line.Computer modeling is now being extensively used inautomotive design, both for form (in the styling andaerodynamics of the vehicle) and in function — especially forimproving vehicle crashworthiness and in weight reduction toimprove mileage.Mechanical and electrical engineeringA prototype of the Polish economyhatchback car Beskid 106 designed inthe 1980s.Main article: rapid prototyping
The most common use of the word prototype is a functional,although experimental, version of a non-military machine(e.g., automobiles, domestic appliances, consumerelectronics) whose designers would like to have built by massproduction means, as opposed to a mockup, which is an inertrepresentation of a machines appearance, often made ofsome non-durable substance.An electronics designer often builds the first prototypefrom breadboard or stripboard or perfboard, typically using"DIP" packages.However, more and more often the first functional prototype isbuilt on a "prototype PCB" almost identical to the productionPCB, as PCB manufacturing prices fall and as manycomponents are not available in DIP packages, but onlyavailable in SMT packages optimized for placing on a PCB.Builders of military machines and aviation prefer the terms"experimental" and "service test".Electronics prototypingIn electronics, prototyping means building an actual circuit toa theoretical design to verify that it works, and to provide aphysical platform for debugging it if it does not. The prototypeis often constructed using techniques such as wire wrap orusing veroboard or breadboard, that create an electricallycorrect circuit, but one that is not physically identical to thefinal product.Open-source tools exist to document electronic prototypes(especially the breadboard-based ones) and move forwardtoward production such as Fritzing and Arduino.A technician can build a prototype (and make additions andmodifications) much more quickly with these techniques —
added. Once alpha grade software has most of the requiredfeatures integrated into it, it becomes beta software for testingof the entire software and to adjust the program to respondcorrectly during situations unforeseen during development.Often the end users may not be able to provide a completeset of application objectives, detailed input, processing, oroutput requirements in the initial stage. After the userevaluation, another prototype will be built based on feedbackfrom users, and again the cycle returns to customerevaluation. The cycle starts by listening to the user, followedby building or revising a mock-up, and letting the user testthe mock-up, then back. There is now a new generation oftools called Application Simulation Software which helpquickly simulate application before their development.Extreme programming uses iterative design to gradually addone feature at a time to the initial prototype.Continuous learning approaches within organizations orbusinesses may also use the concept of business or processprototypes through software models.Software release cycleMain article: Software release cycleData prototypingA data prototype is a form of functional or working prototype.The justification for its creation is usually a data migration,data integration or application implementation project and theraw materials used as input are an instance of all the relevantdata which exists at the start of the project.The objectives of data prototyping are to produce:
A set of data cleansing and transformation rules whichhave been seen to produce data which is all fit for purpose.A dataset which is the result of those rules being applied toan instance of the relevant raw (source) data.To achieve this, a data architect uses a graphical interface tointeractively develop and execute transformation andcleansing rules using raw data. The resultant data is thenevaluated and the rules refined. Beyond the obvious visualchecking of the data on-screen by the data architect, theusual evaluation and validation approaches are to use Dataprofiling software and then to insert the resultant data into atest version of the target application and trial its use.Scale modelingIn the field of scale modeling (which includes modelrailroading, vehicle modeling, airplane modeling, militarymodeling, etc.), a prototype is the real-world basis or sourcefor a scale model—such as the real EMD GP38-2 locomotive—which is the prototype of Athearns (amongother manufacturers) locomotive model. Technically, any non-living object can serve as a prototype for a model, includingstructures, equipment, and appliances, and so on, butgenerally prototypes have come to mean full-size real-worldvehicles including automobiles (the prototype 1957 Chevy hasspawned many models), military equipment (such as M4Shermans, a favorite among US Military modelers), railroadequipment, motor trucks, motorcycles, and space-ships (real-world such as Apollo/Saturn Vs, or the ISS).There is debate whether fictional or imaginary items can beconsidered prototypes (such as Star Wars or Star Trekstarships, since the feature ships themselves are models orCGI-artifacts); however, humans and other living items are
never called prototypes, even when they are the basis formodels and dolls (especially - action figures).As of 2005, conventional rapid prototype machines costaround £25,000.MetrologyIn the science and practice of metrology, a prototype is ahuman-made object that is used as the standardof measurement of some physical quantity to base allmeasurement of that physical quantity against. Sometimesthis standard object is called an artifact. In the InternationalSystem of Units (SI), the only prototype remaining in currentuse is the International Prototype Kilogram, a solid platinum-iridium cylinder kept at the Bureau International des Poids etMesures (International Bureau of Weights and Measures)in Sèvres France (a suburb of Paris) that by definition is themass of exactly one kilogram. Copies of this prototype arefashioned and issued to many nations to represent thenational standard of the kilogram and are periodicallycompared to the Paris prototype.Until 1960, the meter was defined by a platinum-iridiumprototype bar with two scratch marks on it (that were, bydefinition, spaced apart by one meter), the InternationalPrototype Metre, and in 1983 the meter was redefined to bethe distance in free space covered by light in 1/299,792,458 ofa second (thus defining the speed of light to be 299,792,458meters per second).It is widely believed that the kilogram prototype standard willbe replaced by a definition of the kilogram that will defineanother physical constant (likely either Plancks constant orthe elementary charge) to a defined numerical value, thus
obviating the need for the prototype and removing thepossibility of the prototype (and thus the standard anddefinition of the kilogram) changing very slightly over theyears because of loss or gain of atoms.SciencesIn many sciences, from pathology to taxonomy, prototyperefers to a disease, species, etc. which sets a good examplefor the whole category. In Biology, prototype is the ancestralor primitive form of a species or other group; anarchetype.For example, the Senegal bichir is regarded asthe prototypes of its genus, Polypterus.References1. ^ "Prototyping Definition". PC Magazine. Retrieved 2012-05-03.2. ^ Online Etymology Dictionary3. ^ "5.5 Function Prototypes". HP. Retrieved 2012-05-03.4. ^ "Alpha Version Definition". PC Magazine. Retrieved 2012-05-03.5. ^ Bath.ac.uk6. ^ prototype. CollinsDictionary.com. Collins English Dictionary -Complete & Unabridged 11th Edition. Retrieved December 07,2012.Categories:Industrial designProduction and manufacturingPrototypesNavigation menuCreate account