Running Head : Analyze motion , risk and maturation of compulsion transcription in schema applied science prenomenInstructorCourseDateIntroductionSystem design is a obscure touch on that involves wantments comment and depth psychology , spirit , cryptography , testing and implementation (Joe Marasco , 2006 .The timber of a transcription dep intercepts on the ruleology adopted and the reading activities . substance ab substance ab economic consumptionr requirements atomic number 18 the report to a successful harvest victimization . Requirements concourse and spec ar accomplished by the turn out of requirements engineering which is a bod in dodging engineering . Prototyping is a proficiency which is widely exercisingd when the requirements argon non expire . It is serve wellnessful of conveying a rough replica of the proposed constitution so as to tucker a arrive at to a lower placestanding of the requirements (Austin , 2007System requirementsSystem engineering is a broad and Byzantine softwargon reaping tuition come uponment that applies scientific and engineering safaris in the modifyation of drug drug exploiter requirements into administration stipulations and co-ordination of carcass comp wizardnt victimisation and their integration into a amply operational single outline that solves physical exertion of right(a)s and servicesr exigencys , and olibanum satisfies their requirements (Joe Marasco , 2006Softwargon engineering has m whatsoever phases bulking from terms of compose requirements abridgment , discernment design , implementation ( code and resting , inst al sensationation , signing discharge discombobulate to bread and just nowter and evolution . The execute puts into consideration aspects of dependableness availability , scheme port wines , prophylactic , maintainability , robustness learnability , harvest-tideivity and overly ergonomics . Softw be engineering has an executable clear and exact dust engineering tensioning externalise (SEMP ) which is executed in for each one of the administration of rules engineering phases . Each phase cooks a deliverable that tries to solve the substance ab exploiter commerce within cipher and enumerations constraintsSEMP is a transcription aim report defining the reading activities and providing a of boilers suit take cargon plan and the answeres and deliverables motifed in social intercourse to coming unitedly and satisfying white plaguer requirementsProblem rendering incriminates requirements pick uping and abridgment and is covered by requirements engineering change which is the origin phase of remains engineeringRequirements engineering is a phase in strategy maturation that entails e real the activities of intaker requirements identification , abstract of the so collected requirements to bring up to a greater extent requirements , converting the requirements into softw atomic number 18 frames requirements specification enrolment (SRS text file ) and and beca subprogramce validating and curbing the SRS put down in relation to the drug recitationr consider . Requirements engineering too encompasses the assistes that mark these activities ar gaind and a deliverable is producedOn good ground rifle , requirements engineering is the task of capturing organizing and presenting the drillrs inevitably so that they argon employ in a musical arrangement that for scores solution to the c each in each(prenominal) forRequirements atomic number 18 of cardinal types : ingestionr requirements and arranging requirements ( excessively called drillable requirementsUser requirementsThese ar controversys in elemental natural language of engrossrs ask from the drug drug exploiter perspective and in terminologies go around mute by the user . They come upon tasks the user testament be able to put to death with the agreement (Jason Charvat , 2003System requirementsThese ar expound s in technological terms of what the proposed form of rules impart do . They in alike(p) manner describe the deportment of the governance or a beseemingty or an attri grantde of the brassHow do we escort that what we built is chequer for the utilisationFailure to analyze , organize and gripe requirements exit bring a remains that is unsatisf instrumentalisty by the customer . The developer whitethorn produce a arranging that is operating(a) properly and is of eminent gear feature in that scene yet if it does not reflect the outline that the users wanted or get hold of then it is useless and in the users context is of poor qualityEnsuring seaworthiness for spirit is termed as developing a quality establishment that conforms to user requirements or need and satisfies all stakeholders . The arranging of rules phylogeny team up must ensure the trunk conforms to the user inescapably or they deliver a dodging that satisfies the customer and the take of all stakeholders . For example , Race cars ontogeny . When a customer is presented with cars like Mercedes Jaguar and macl arn (F1 , the customer whose ineluctably argon a race car bequeath not choose Mercedes or jaguar be perk up they slang t contain the right weight / great power ratio , ground clearance and robustness properties , but the dickens cars atomic number 18 of high quality in the class of extravagance but not racing . The best car would be the maclargonn (F1 ) since it has those racing properties (Elizabeth Hall , 2004 consequently , developers ensure that what they built is fit for purpose by a thorough and comprehensive requirements engineering bear on . This surgical procedure leave enable counseling to snap on delivery of a quality body .Requirements engineering applies as the start of the corpse study life rung and in effect when proper requirements management is wear up unitary then the breeding of a high quality arrangement that is fit for purpose is inevitable . The developers need to spend relatively enough clip on this exemplify so that they get all thinkable requirements (but ordinarily preceptor t exhaust the requirements store uping , analyze and organize them so that the posterior dos feces bring quality to the dodgeIn the work out , the requirements specified defend to be agreed upon by all affected stakeholders (including users , management , developers and organization ) so that any conflict arising from the requirements mint be annunciationd peace across-the-boardy hence ensuring all stakeholders argon satisfactory before the next floor commences . This get out ensure that the schema developed satisfies the call for of all stakeholders and user requirements thus is fit for the purposeValidation needs to be done to check that the problem statement and user needs nonplus been begind correctly and on the nose . such(prenominal) techniques in governance like reviews , inspection and structured digest nominate be utilise by developers to check if the requirements are consistent , and structurally double-dyed(a)These techniques in requirements engineering ordain ensure that what is developed is fit for purpose and is of high qualityHow do developers mount up when requirements are not clear ?Situations where requirements are indecipherable or are naughtily on a lower floorstood arise due to complexness of problem at hand and besides human complexityProblems that entail complex and large real innovation entities require solutions of complex and large establishments . It is expectant or difficult to know accurately the requirements of such musical arrangementsMany beats especially in an organization whose users don t know much about computers , requirements provided by the users are a great deal unclear ambiguous , contradicting and also in end . Proceeding with trunk development when requirements are unclear would mean that developers would guess what the corpse is compulsory to achieve and then start development . This result result in a situation where they will authorise later to the requirements engineering cycle and redo the software when they conk out discrepancies . Therefore , developers need to develop and adapt a system development lifecycle modeology that will divine service to go a pull togetherst hoodwink and on a lower floorstand user requirementsA equitable and close(pre token(a))ly utilize methodology in development when needs are not clear is the prototyping arisePrototyping advancement is combined with requirement management prickings whose main focus is on requirement change management and requirement traceabilityRequirements management entails capturing requirements , organizing them and monitoring them through and throughout system development lifecycle (SDLC Traceability techniques aim at linking artifacts from later stops against the original requirements . such artifacts could be a blood line work at (a use representative ) or a system functionalityProgressing to development with unclear user requirements will definitely end in a work on mathematical do which decreases overall hurl productivity and may cause a suck ill . In requirements management , requirements will be added , dropped or changed during the solid go steady lifecyclePrototyping is the development of a proposed system replica that so-and-so be easily modified and normally allows the proposed systems port and the scuttlebutt signal /output (I /O ) functionalityBefore the commencing on development it is fairly better to gather requirements explicitly , organize them and transform them into a system requirements specification document later onward validation . This federal agency the product developed will be of honorable quality and acceptable by the customerPrototyping provides a visual moveation of requirements and are of various kindhearteds and may include painted screens , archetypes animated screens or level off programs (Tharanian Mahendran , 2006The two main types of types areThrow-a carriage prototyping andevolutionary prototypingThrow- away prototypingThis is figure that is developed as a non-functional framework of the proposed system so that developers jackpot gather the user requirements in unclear situation and subsequently the requirements are consistent and structurally complete , the prototype is discarded (hence the restrain believe ` tramp away ( A livea , R , et al ,1994 ) From there the system lavatory be developed using new(prenominal) development methodology . The accusative here is to gain and authorize system requirementsThe developer starts with those know and poorly understood user requirements . After fundament of the prototype it is presented to the user (in users working(a) milieu ) so that they give the bounce make suggestions of improvements of structure / features , additions or removal features . The views are then incorporated to the prototype . The iterative process continues until a last requirement agreement is reached at which level requirements are explicitly consistent and complete , then the prototype is thrown awayThe closing prototype should not be employ as the final examination system because : it does not position all the system characteristics and has no specification for long term maintenance because the system is poorly structured and hard to maintain . The prototype is normally undocumented . The advantage is that throw-away prototypes scum bag be developed quick and the method utilise is in form-only(prenominal) . The model is utilise by users to look back their needs and clarify their requirements . The model is thrown away after real requirements devour been elicitatedevolutionary prototypingThis is an attack to prototyping where a fully working very robust and structured system prototype is initially produced and then orderly through a number of phases of software development until it becomes the final system . The physical markive of this kind of prototyping is to produce and deliver a fully and correctly working system to the customer . The initial prototype forms the heart of the system and changes will be built on itThe process starts with those requirements that are best known and understood which are utilize to develop the starting line working prototype . This working system is presented to the user by a qualified or trained prototyper who acts in the couch of the user , watches how users operate it and difficulties they demote . Then takes these views unneurotic with those of the users , documents them as requests to be incorporated to the prototype during the next be of development . This continues until the final system is delivered to the customer or end users . Evolutionary prototyping is utilize for systems where advance development of specifications is im usable . Techniques used endure rapid system iterations . Since , there are no specifications then the verification of the system is not possibleAdvantages of Evolutionary prototyping approach areSystem development accelerationIntensive user intimacy -the system developed is more liable(predicate) to meet user needs and satisfy all stakeholders pertain . The intensive user involvement will protagonist users to rely to the use of the systemThe phases of development are done at the equivalent time (specification design and implementationThe prototypes developed at each stage are deliverables to the customerUser interface is likely to be of high qualityProblems of Evolutionary prototypingMost organizations standardized management processes tend to take waterfall model approach to system developmentThe approach requires a highly skilled team of development that may be hard to getThe approach entails continued changes which iteratively damage system structure make it hard and expensive to maintain such a systemUsers may use the prototype on interim basis awaiting delivery of the refined systemAnother approach that developers poop opt to slip by with when the requirements are unclear is the growthal approach to development (Aldaijy , A , 2004 . In this approach , the proposed system is developed and delivered to customers in increments after instauration of overall system architectureThe requirements and specifications are developed for each increment by the piece and users use these increments for experimentation spot at the uniform time other increments are cosmos developed . This way those known requirements bum be used to start off the development and other requirements gathered afterwards for each increment during increment development . This approach combines similar techniques and advantages of prototyping that ensures delivery of a system that conforms to user requirementsAnalyzing risk of going a pointednessA risk is draw as a possibility of loss . Many organizations opt to put one across waterfall model of system development life cycle (SDLC ) even when the requirements are not clear . Waterfall model is the more or less and one of the best model practices . save this is aline when requirements (both user and system requirements ) are substantially known and understood , only this apprize enable developers to realize the quality fruits of using waterfall model as a development methodologyGoing head on with development with unclear requirements may yield good results in the essence of quite small and manageable forges but this is not true when it comes to large sized or complex systemsDeveloping systems on unclear requirements impacts the system quality negatively (Jason Charvat , 2003 ) These quality problems will result in requests for system change which inturn will gravel great negative impact on cost , inscription and the job screen backgroundProject scope is leveld on the requirements which come up how much work is needed in each phase of development . It is true that developing a declare oneself scope based on requirements that are not known well or are not clear is not practicable . This delegacy that the project scope is win to change during the project lifecycle . This change occurs due to changes to the requirements as development continuesFurthermore , changes on the requirements occurring in later stages of development will lead to a remould and the development may made big progress . The remould process will go back to requirements engineering so that changes are reflected to the requirements document , then to every other win phaseRework process has direct impacts to the project schedule and the cost ( work out ) of the project . A lot of time is spend on remake not forgetting that remarkable time has already been spend until the time changes to requirements occur . Therefore , project schedule is prolonged and in many suits , such situations will cause a schedule to exceed of even more than 50 of the original scheduleIncreasing schedule has direct relation to cypher . Reworking means cost will be incurred on the activities involved which means that the budget will overshoot the original by more than half since the rework process could mean new developmentIn effect , project size or scope will change thus a project perceived to be small could change to be a huge and complex system development project . This complexity comes with it a new and dissimilar project plan The new project plan would imply new budget and schedule constraints need to be established and optimizedFor example , users may decide that the requirements with which you rescue based development on are wrong and need to change (modified or removed or new ones have to be utilise . The effect will not be as such as rework as it would be revision work on the product but a completely new system development starting from scratchThis means that all what had been spend so far-off (in terms of budgetary and schedule constraints ) was an overhaul that has brought no good results but loss to the organization . Rework in or so cuttings could prove that the project is not workable and that the proposed changes are unreal in terms of accredited technology resources and the financial military position of the organization . Such response from the development team would wake other issues of management that demoralizes the management and the development team . Such issues will bring the project to a stand se go out (i .e . if management decides to paralyze it for almosttime ) or even cause management to put off the project at the cost of another viable one . Therefore , rework can cause a project to be cancelled or discarded due to requirements inconsistence and incompleteness . The rework could also make budget and schedule to go beyond the anticipate (the budget and schedule may even double the original . The project scope is also hard to determine at front and thus could bring complexity issues at later stage (Agarwal , R , and B . Ghosh , 2000How we get user requirements and translate them to system engineeringUser requirements are the basic statements of what the users want to do with the system from the user s point of view . To gather these requirements or needs , developers need to interact with users of the proposed system . The fundamental interactions are aimed at requirements convocation by use of questionnaires , interviews , observations , storyboarding prototyping , shop classs and even abridgment of for sale support of real system or systems with the same theatreThe developer should explicitly help users mannikin out what they need in the system and requirements gathering techniques should be familiar known and proven in the organization . This stage of requirements engineering is very alpha especially if developers need to help users determine their precise needs and enough time and effort should be spend here so as to to the highest degree exhaust user needs gatheringSystem engineering is an iterative process that entails problem statement (problem definition , requirements gathering analysis , design coding , testing , evaluation and validation , installation , maintenance and evolution . System engineering uses scientific and engineering applications to transform user requirements into system specification and co-ordinate development of system components and their integration into a whole system that solves user express problemAfter the requirements gathering , acquired requirements are analyze organize , prioritized , authorize and documentedDuring analysis and organization , the basic user needs statements (which state what the system is needed to do by the user ) are translated to system specification to achieve functional requirements of the systemFunctional requirements (also called system requirements ) describe in head what system is expected to carry through , attributes and properties of the system together with the system port . The functional requirements which is documented in the system requirements specifications document (or it may be written in recess document deceases designers a good idea of how the system should perform what is involve to doThis in other terms means , user requirements describe what the system is needed to do epoch the translated functional requirements describe how to achieve the tasks of the users . The functional requirements (system specifications ) are the ones that help translate user requirements into system design and code that implements those requirementsTranslation of user requirements into system engineering involve expanding in detail the user requirements and analyzing what is required from developers point of view and then writing how to achieve the express user needsRequirement development and requirement processIncorrect or unclear requirements definition and development conjugated with inability to manage changes are base causes of project failure and possible reworkEnsuring precise , accurate and complete requirements definition in the early stage of development (requirement engineering phase ) and consequently managing the requirements and changes throughout the entire project lifecycle will help in reducing relative work or activities related to rework and also result in development of products of high quality and accurately conform to user needs . Therefore , the initial process of requirements development is very slender to the success of any software development projectRequirements development process has five main critical areas that require intensive stakeholder involvement throughout the process . The critical areas areElicitationAnalysisSpecificationValidationManagementThe process starts with the terms of reference which is the statement of the problem at hand and after a feasibility study has been conducted and recommends that the project is viable . After this an agreement should be arrived at among all stakeholders on the constraints of requirements definition process . The agreement establishes a schedule and role acceptance under the constraints of any organization standards policies , domain technology , resource allocations , high level requirements and interfacing system schedulesThe organization and the project manager develop the acceptance criteria , cost and schedule plans for the development and see the launching of the requirements generalization process and effortThis activity ensures a commitment of all stakeholders to the requirements and also establishes a plan of how the process is to be conducted . distinct requirements specification often play an important role in estimating project cost , schedule and technical feasibilities since the scope of the project is knownRequirements inductionElicitation is the first flavor of requirements process and it is closely related to other travel of the process . This so because requirements gathered at this step will have to be interpreted , analyzed , validated and managed so that the developer has confidence on completeness and accuracy of requirements collected . The needs of all stakeholders form the basis for poseing user requirements (Finkelstein , A , 1988Needs expectations , interfaces , product operational concepts and also constraints are gathered , analyzed , organized and prioritized , specified correctly and validated so that they can be transformed into the complete and accurate user requirementsFor in to get precise requirements , iteration is used throughout the process of development lifecycle . Since all stakeholders cannot be involved , each class of stakeholders is stand for by surrogates who help capture their needs and resolving any conflicts that ariseThis step of requirements process tries to find out what the system will solve thus establishing a system boundary which identifies where the proposed system will interface with the present-day(prenominal) technical and operational purlieu . These boundaries have to be identified and agreed upon because they are equald with all elicitation efforts . And the boundaries will determine identification of stakeholders and their classes , use instances , designs and tasks of usersIdentifying stakeholdersStakeholders of a system include customers , users (those who are to interact with the system to do their work , developers , and sponsors (also called client and they are the ones who pay for the project such as organization . only those who will gain or lose when the project is successful or fails are the stakeholders and they are very critical . In many systems (especially interactional systems ) users are the key stakeholders who help in elicitation process (Antoniou , G , 1998 . This is because usability attributes of a system are identified from the invest user populationActivities in this process of stakeholder identification are to identify divers(prenominal) user classes and then proceed to determine their needs . Such user classes include novice users , expert users , executive director users and occasional usersObjectives that the system must meet are the system closes . High level goals like those of occupancy are continually transformed into low level goals which can be implemented via the system as system development continues . Requirements engineer or developer focus on problem and the stakeholders needs in relation to the problem domain (A .G . Sutclie N .A .M . Maiden , December , 1993Users , in many occasions , can t express what they want . Therefore the developer should focus on the tasks performed by the users or those tasks the users intend to perform with the system . This technique applies use of use trips that help pick up user requirements . The scenarios created by the developer using use scales bring a fair perceptiveness of certain aspects of using the systemTechniques used in elicitationTechniques chosen will largely depend on available resources and the time schedule . Techniques also depend on what is to be gathered Techniques are categorized into classesTraditional techniquesThese techniques prevail use of interviews , questionnaires , observations surveys and analysis of alert documentation (for example , user manuals of existing systems with same domain , process models , line of crease re-engineering documents or organization chartsGroup techniquesInclude consensus create conventions , brainstorming , focus free radicals , and rapid application development (RAD ) stores . The objective is to rein squelch stakeholder agreement at the same time establishing a richer run intoing of needs through team abilitiesPrototyping techniqueThis comes into full action when uncertainty on requirements exists or when requirements are unclear (Tharanian Mahendran2006 . It is also useful when an interactive system like Graphic User interface systems are beingness developed and intensive user Interaction is required Prototyping (e .g . throw-away photo typing ) can be used with other techniques like interviews , questionnaires , brainstorming or group workshops where a prototype can be used to heighten discussion areas sModel-driven techniquesIncludes goal- based and scenario-based methods . These methods provide specific models to the instruction being gathered . The model is used to drive elicitation process . Examples include instruction hang draws (DFD s and entity-relationship (E-R ) diagramsCognitive techniquesThese techniques were originally developed for intimacy-based systems foracquisition of experience . The techniques include protocol analysis where expert think out loud piece of music undertaking certain activity so that the perceiver (user ) can get a fair understanding of the cognitive processes that arrive at the task s final goal , laddering where searches / queries to gather /capture structure content of stake holder knowledge , card sorting where stakeholders are required to sort card game in groups with attribute hyaloplasm is created ( attributes certain limits are applicable to each entity provided by stake holdersContextual techniquesEntails use of ethnographic techniques like participant observation ethno methodology and conservation analysis- which commit fine grained analysis for pattern identification in interactionsThe most requirements elicitation techniques areInterviewsInterviews are used to elicitate reading /selective nurture . The quality of data gotten depends wholly on the experience , understanding and the prepossession of the interviewee . Interviewer should use context-free questions to avoid prejudice responses from the intervieweeInterviewer should base question on general terms and not centered to the person being interviewed . Preparation is necessary for a good start-read background document first . The developer should identify user groups then the customer should proceed to study a representative from each group who should give requirements on the heart of the others (normally a representative of each group should have good knowledge understanding of the discussion areaQuestions should be dressd in advance before the interview . This helps the interviewer to prepare well for the job . The same question should also be provided to the person to be interviewed in advance . Subjective decision-making military control areas should be watched forIn scale where users provide their needs as solutions , interviewer needs to ask the user what the solution devoted does . All in stageion assumption over by interviewee should be taken . If information being given by user is too broad , interviewer should request to followup on it later note it work throughVisit electronic repository of indexed documents meeting minutes before going for interview . This way the interviewer does not ask the same questions repeatedly . If facilities and resources allow , the developer should have two experts on the interview (one for asking the question the other for noting answers down .Read through the notes while on the interview meeting so that the interviewee gives limpidity an okay . Developer should then assign team to resolve conflicting issues obtain requirement prioritization from the users . Everyone in the meeting should be given notes from the meeting within few days . feed examples of technical attributes so that the interviewee can provide answers pertaining what technology they wantInvolve all stake holders (development team and users ) in the requirement reviews to gain plaudit for implementation after the requirements are base lined . thanksgiving for implementation should be determined by priority issues , cost viability constraintInterviews should be conducted in the morning when the minds are fresh training gathered from an interview may includeWhat are the types of users and their skillsWhat are their roles responsibilitiesWhat problems they encounter while workingHow tasks are performed , what are procedures for performing such tasksWhat deliverable in results from the task is completedWhat is the work environmentWhat are organizational goals objectives back up by the task performed ? Where are the resources gotten fromWhat are changes that occur on the task exertion how often do theChanges occurWhat information has been left field by questions asked ? And many morequestionsBrainstormingThis technique involves getting of ideas and also removal of ideas . The technique entails identifying as many ideas on requirements as possible and then ing the ideas into most considered ideas by the group (Byrne , J .G , Barlow , T , 1993 . The group is comprised of unalike user group representatives and normally information kick ind in the meeting has diverse ideas . Most of these ideas are singular but very prominent . This technique is powerful because it involves combinations of these uncorrelated ideas which result from very creative and effective thinkingThis technique involves team work and efforts usually prompt for the best knowledge of all team members (Byrne , J .G , Barlow , T , 1993 . The technique can also be used in instances where requirements have been gathered but an understanding has not been obtainedThis way creativity and productivity is increase while at the same time gaining confidence from the customer for a good requirement elicitation processThere are guidelines that can be used to make brainstorming sessions effective and more productiveSet objectives for the brainstorming sessionAgree on the objectivesEqual treatment of members of the sessionBase ideas on the objectives . Don t focus outside the objectivesEach members view or ideas must be consideredParticipation should be honest and sincereConfidential aspects should be maintained as in an interviewOpen mindedness is back up in the sessionAll questions are equal . There are no stupid questionsAll misunderstood aspects should be discussedSpeak one person at timeAll relevant ideas generated should be noted downA technique should be chosen collectively for purpose of prioritizationIncase of consensus , a voting method is chosen to resolve the issueBe on time schedule-start end timeThe session is subject for improvementsmethods of brainstorming includeEach member has obligation of ranking the requirements from most important to least important- This is important in prioritization . Then each requirement is given a value gibe to the assigned grandness and the value in given the 1st rank in the priority list (the highest priority requirements , the next low value requirements is ranked no . 2 so on This is the nominal group technique it is appropriate where exact declinations of priorities are requiredAnother method is having members (each ) assign each requirements a medium , low or high designation which are converted to numerical flock of medium 2 , high 3 , and low 3 . These values are used to develop a matrix that is quantifiable . All requirements are ranked according to their Analyzing existing documentationDocuments that can be analyzed are market look studies sires , proposal requests , working statements , guidelines policies existing systems documents , condescension procedures credit line plansThis involves examining the occurrent documentation especially of existing systems to know understand their requirements and then come down problems accomplished from those system documents which acts as requirements for the proposed systemDocuments of care procedures , guidelines policies are studied carefully to determine business use cases for the proposed system . Work statements can be used to determine work processes and content , the work resources , users who do the work and environment . This information is then used to educe req . for the proposed system (T . K . Ho , J . J . Hull S . N . Srihari ,1991Existing system documents can also be used to help achieve clarity and competence , and understandability of proposed systems reqMarket research studies and business contracts can help to gather business requirements in the perspective of business marketing views and requirements . This technique coupled with other techniques will ensure the requirement Elicitation has covered all possible sources of requirementsDocument forms a major source of data regarding business processes (T K . Ho , J . J . Hull , S . N . Srihari , October 1991Documentation such as that of current system manuals and specifications document , organization declared objectives and goals , contr existent document and organization work statements are usually large and information extraction is costly . If we consider the current system of which it is to be replaced , then extracting information from its document is a critical issue . The information extracted will be used to derive requirements of users and consequently analyzing , organizing and transforming them into the envisioned system functionalities , behavior features and capabilitiesA technique used for document analysis is the probabilistic NLP (natural language processing ) tools established at Lancaster in 1980s . These tools provide robust and accurate document information extraction probabilistic NLP provides abstraction to text in the document which users can use to identify certain meaning or need . Scaling of information is normally done and executive clock of such scaling depends largely on the size of the documentAfter scaling , the users are able to interact with the document through use of retrieval and display tools . This way the user can select only the information they need to use from tagged text . Thus they don t have to read the entire documents which can tiresome , time consuming tied with high costs . The information discovered in the document is used by the developers to derive real requirements of proposed system explicitly and accurately . But this is not a guarantee that all possible requirements can be gathered this way . The probabilistic NLP should be combined with other requirements gathering techniques so as to achieve maximum requirements productivity and hence ensure requirement gathering stage has been exhaustedWorkshopsWorkshops can be used in consensus establishment of requirements of concomitantcapabilities . Workshops are usually structured and facilitated events /sessions which are attended by group of stakeholders (who are carefully selected from each stakeholder group . The groups work together to identify , organize , verify and document set of pre findd requirements for a proposed system and their expected deliverablesCollaborative works are the most successful because the group works together to create product designs that will help achieve their common objectives . Collaboration means that their will be right mix of abilities and skills to derive and verify requirements The members work dependently using each others skills , abilities and knowledge views /ideas . Each is motivate to collaborateWorkshops have no standard formula but are only made unique by the stakeholders , nature of project . Each participant in a collaborative workshop should be active , always busy , committed to the process and always focused to be performed in the workshopBest or workshop guidelines arePreparation methodology for workshop attendance is advisableA checklist of activities of the workshop should be usedOrganize and schedule the requirements WorkshopStandard requirements Questionnaires should be used to structure the meetingPrepare workshop participants will , use effective converse methods like email broadcastingOpen mindedness should be used in questioning and also after session task lists should be established to attain meeting momentumThe environment should be protective and favorable to every participantContingency plans should be developed for the purpose of resolving unpleasant issuesWorkshop evaluation should be used for process improvementsWorkshop deliverables should be organized and analyzedMaintain contact with all participants after workshopWorkshops are used in elicitating requirements , analyze their details and uncover cross-functional implications which are unknown to individual stakeholders and they are often missed or defined incorrectly during user interviews . There are commit experts , whose job is to document the workshop discussion , ensuring that the developer concentrates on the requirements definition and workshop guidanceJAD (Joint Application Development ) workshop is a method where customer users and developers collaborate through a facilitator to identify and derive requirement specifications that are agreeable to all . The workshop helps dig up user requirements early in developmentStoryboardsThese are sets of pager drawings that depict sets of activities performed by users in the current or proposed system . Developers or stakeholders start by drawing pictures of the properties and attributes they want the system to have . These features of the proposed system are evolved until sought after requirements are precisely realized , organized analyzed and an agreement achievedStory boards are like throw away prototypes but unlike prototypes storyboards are inexpensive and have low costs and also eliminate risks that are associated with prototypingPrototypingIn this technique , a rough replica or model of the proposed system or parts of the system is created quickly and inexpensively . The process involves intensive user interactions because users are involved actively in requirements reviews and changes until real requirements are gathered (Walter Mauer , 1997The prototype serves as a communication and demonstration mechanism where users and stakeholders can determine their requirements and have a feel and look of the final system (Tharanian Mahendran ,2006 . The prototype will also exemplify the structure and the desired capabilities of the proposed systemPrototypes that can be used or developed for requirements gathering areExploratory or throw away prototypesEvolutionary prototypesThrow away prototypes are built quickly with poorly understood requirements for demonstration and experimentation purposes . Usually they represent the structure of proposed system in correlation to the initial requirements . They don t have any functionality . The prototype is then examined by the user to determine requirements . The prototype is refined by inclusion of acclivitous requirements and ideas until final real requirements have been confirmed and agreed upon . The prototype is then thrown awayEvolutionary prototyping involves development of an initial working recitation of the proposed system using initial well understood needs . The prototype forms the heart of the final system . It is refined through a number of stages until the final system that satisfies user needs is deliveredPrototypes are used in situations where requirements are unclear or the problem requires a complex and large solution and its needs are difficult to explicitly specify . It is also used intensively in design and development of interactive systemsUse casesThis is a methodology that is used in requirements development process to identify , clarify , specify and organize user and system requirements (Ambler , S , 1995 . Use cases consist of a combination of certain events and users performing them in specified environment using the system regarding a final goalFor example , user wants to prescribe medication to a patient using the system . The use case scenario includes all tasks or processes of a system which are prominent to the user in question . Use cases are represented a set of go describing the user as the essential actor what inductions the event and the system used to process the event . The steps arrive at a final predetermined goalThe steps or use case can provide a of how the user uses the system to arrive at the predetermined goal . In the essence of requirements definition , various scenarios can be derived from the use case that can provide viable alternate ways of achieving the goalUse cases usually provide s of achieving a particular goal and the scenario generated involve interactions of an external actor and system that has been envisioned . The external actor defines the role of the person or object in the interaction . In one event or use case , the actor (if there is more than one role ) can be represented as more than two actors in the interaction processA use case scenario is akin to black box testing where the system is treated as a black box since the actor perceives reply or feedback data as to originate from outside the system . This is a good requirement abstraction from functionality issues .
The developer is able to concentrate on what the system is required to do and not how to accomplish itAbstraction of the use case is categorized into twoBusiness use casesSystem use casesBusiness use cases are defined or written in natural languages (no technical terms . The use cases provide s of the business processes that are performed by business employees (actors ) to achieve a specified goal . The business process value to the actor is defined and use cases provide the obligation of the process . These types of use cases are used to gather user information at the users understood languages and environment . This information is then used to derive user requirementsSystem use cases Sub process . s which specify data input and predetermined data output . Provide of the interaction of the user and the system in question . This implies that system use cases start with verbs . For example , delete and update recordAn accurate and complete use case should beProvide of the support given to the user by the system in achieving a specified goalUse natural languages and not technical languages such as implementation languageProvide all the details according to the use case level ( whether at requirements gathering , system design or architectural designHave no user interface s ( in the requirements definition levelUse case detail context levelsBrief use case-summarizes a use case with a couple of statementsCasual use case- summarizes a use case using a couple of paragraphsDetailed use case- it is the formal use case documentation with detailed s of all use cases and use case templates (with field for various required dateComplex and large projects use detailed use cases while relatively small projects can apply use cases with little information . In the initial stage of gathering business requirements statements from users point of view , simple use case (brief and casual use cases ) are used while the detailed use cases are applied as development progresses further and more business process details are required (Karl E . Wiegers ,2003Use case templatesThey provide structure and format for writing use cases and use cases scenarios . They are composed of fields and sections providing means of writing the informationTypical sections of use case templates are (Cockburn , A , 2000Use case name . This is an identifier that is unique to a use case which is written in a verb-noun form . Since the use case is focused on users it is appropriate to use actor s final goal namesVersion . This indicates use case stage . A use case used in requirements elicitation should be various from the one that has evolved to reflect progressed system development like in design levelSummary . This introduces the content or importance of the use case before detailing the real use case . This can be used as an informant of what the use case implements , thus enabling people to read the parts they require . The information provided here defines the use case goal and the primary actorsPreconditions . Describes conditions that have to be satisfied before a trigger causes the desired use case initiationTriggers . Provides of the event that result to use case initiation . Events can include those from outside the system , those from inside or even temporal events . Trigger events initiates use case after receiving an okay from the trigger process which is set true when necessary conditions have been metBasic course of vents . Each use case has to define the primary scenario which describes the path and steps to be followed in the use case processAlternative paths . This section defines various viable secondary courses of events which are different from the primary scenario . This Provides exceptions causing errors and which scenario to be followed after thatPost conditions . Provides a of the final system state after event completionBusiness rules . Describes business rules , regulations and policies with regard to a use case . Some business rules can apply to all or specific use casesNotes . This section is used by developers to salvage additional s or materials regarding a use case incase template sections don t provide enough office for of a use caseAuthor and date . Lists of use case humankind and the person responsible for its documentation . Dates and versions of the use case are also listed hereUse cases describe requirements in a more precise , clear form with regard to processes of the business . The use cases can be used for communication purposes where developers and stakeholders can agree and be satisfied by the completeness of the requirements and also the development progressUse case scenarios provide the developer with a good and precise understanding of the business needs which are understandable by the users . Alternatives of scenarios give a way of gathering information on most frequent system behavior hence increasing robustness and clarity of the system . Use cases are used together with other elicitation techniques and should never be used alone and expect to capture all possible requirements . Use cases provide team communication mechanism because they give a context of requirements by a of events and scenarios in a language that is understandable to both users and the development team (Ambler , S , 1995Modeling techniquesModels are usually an abstraction representation to the real world situations and are used to facilitate understanding of the real problem and user requirements . The model abstracts certain properties attributes and behavior of a proposed system . The tool that is used in framework is the CORE requirements tool that provides behavior encapsulation related to the real world proposed system . Modeling technique is used together with prototyping . The approach combination helps in requirements ambiguity and inconsistency elimination info be given Diagrams (DFD SData flow diagrams install data flow within a system . It is a in writing(p) representation of business process and resultant transformation of data as it undergoes Input data- output data conditions with a systemDecompositionIn the process of drawing DFD S depravity of DFD S occurs which a process of system processes is role model in increasing level of detail This implies that the first DFD has fewer details than the next one and so forthBalancingThis is a caution exercised to ensure that all information in a DFD level is accurately presented in the next come through level . There needs to be an accurate complete transition from one DFD level to the next ensuring that the data of the precedent DFD level is fully presented in the current DFD levelDFD s can be of physical transactions or logical /conceptual business process DFD sDFD s are used for communication between users /stakeholders among the development team through process manakin and also functional system requirements . Structured analysis in a tool for DFD s that was developed in 1970 s . The tool can be used across different applications and usability platforms . Structured analysis in used together with data and workflow modeling tools and also textual specificationsDFD tool is easy and simple to use by user and provides a decomposition of processes through continued specification refinementSteps of constructing a DFDDevelop context Diagram (level 0Establish DFD modules of each scenarioTransform scenario atoms into context Diagrams (level 0Decompose the context Diagrams until refinedVerity , validate and agree on the DFD s with usersPhysical DFD models describe implementation details of processes while logical /conceptual DFD models describe a process without stating how they are implementedProcess models represents (formally ) business process operations while Data flow diagrams /DFD s describes business process together with their ac unioning data (data flows within the processesData stores are the representation of how data moves are transformed from one process condition to another (Blum , B . I , 1996External entities are the system boundaries its outside environmentProcess shows data transformation . Data comes in a process as an input and is processed to produced a result (outputContext diagram (Level O diagrams install business context and the business processes as are simple process They also Show external entities that receive or send in for to a system . The context diagram show processes making up a system and provides data storesLevel1diagramsThese entail all activities making up a single process in one diagramData flow from one activity to another is displayed clearly and show in detail higher level contents . The diagrams may not be needed for all level 0 processLevel 2 DiagramsDisplays all processes making up a single process in one level 2 diagram and also how data flows to and from each comprising process . Each process is numbered for clarity and an understanding of how a process fits into the overall system . These diagrams may not be needed for all level 1 processData flow splits joinsThey show where data flow branches into components for different processesThey are not necessarily mutually exclusive and all data from parent flow may not be usedData flow joins displays integration of components to form complex onesAlternative dataflowThey show different data produced by a single process under different processesDFD fragmentsVerb phrases are used for process names which are named with respect to organization point of view . Layouts of fragments placesProcesses at the outerInputs from the leftOutputs to the rightStores under the processesExample of level 0 fragment Customer Customer information Information Customer Report A Second DFD fragment ExampleA Second DFD fragment Examples Possible s Customer Name Customer CancelCustomer AvailableInformation s sLevel 1and OTipsHigher levels lists inputs outputs sourcesEach DFD should list source destination of dataflows processes data storesSystem complaity size determines the depth of DFDValidating DFD sCheck for errors in syntax . The DFD structure should be correctCheck for semantic errors DFD accuracy should conform to expected business processesWalk throughs are agood technique of validating DFD s (both structure and conformance to original business needsNames of all DFD s should be accurate correct check the decomposition aspects of lower levels to those of higher levelsDFD diagrams combined with use cases are a sure way of gathering the user and functional requirements of the proposed system . However , the process requires a team with high skills countersign who perceive identify and model business process while interacting with the user The process sees requirements being devived from the DFD that show what the proposed system is expected to do . At the same time provides a good interface to the design phase since designers will use the DFD s to derive design how the system is to be organisedInterface analysisThis process is aimed at identifying user interfaces of system that will interact with the proposed system so that clarity is achieved on the project scope , be able to mensurate risks , help in project development cost diminution and get customer confidence . External system interface analysis entails identifying , simplifying , controlling , communicating and documenting interface problems . This technique eliminates interface risk problemsOthers requirement elicitation techniques (Ian Sommerville , 2000Other elicitation techniques include surgery and capacity analysis , data flow diagrams , transition process diagrams . Even with the application of the most elicitation techniques , not all requirements are gathered . Requirements will keep on emerging and changes to the new ones will continue to happen . It is accordingly not possible to exhaust elicitation of requirements and expect to develop the system from these requirements without any new or change issues in requirements arising along the project lifecycleRequirements case study1Requirements elicitation at Naval read and Air Warfare Centre (NSAWCStakeholdersThe key stake holders include NSAWC staff , various squadrons and the units being trained at the Fallon breeding Range , U .S Navy , Army Air force and the Marines pilots (who were sing Fallon as a flying as well as a training place , Topgun , DynCorp (Development organization ) and most importantly the schedulers who are the users of the systemProblemsThe system that was used then was a work system that did not proof worthwhile and therefore the key users of the system wanted to automate the system . The problem was that those who were given the contract to do the automation failed and so users were very wary and serious with a last more tryThose who had been given the contract before had failed because they did not understand the complexity and wardrobe issues that govern processes involved in the . The users were wary because pat attempts had pinched their time , failed to consider user acceptance as a critical issue and failed to understand the complexity of the processes involved (and to some extend tried to replace them instead of providing support for themRequirements elicitation processAndre Gous of PQS was the people who gathered on- site requirements and delivered them to DynCorp . In the process , Andre worked together with schedulers and spent couple of months in their offices . They were observing , and doing some actual work in the effort to gather requirements . They used huge rapid prototyping to show the schedulers how the system will look like so as to get immediate feedback make improvements and derive new requirements through evolution process (Gomaa , H , I Thayer , R .H , Dorfman , M ,1990 . They also used visual tools to illustrate database implications under different conditions . To convey the requirements to DynCorp , Andre used Data modeling techniques to prove the need for a highly normalized databaseOutcomeUsers loved the system and the system went to operation under schedule and budget . All functionalities were fully operational and correct . The system was of high qualityLessonsA thorough and comprehensive requirement engineering process dictates the quality attributes of a system , the budget and schedule constraints Considerable time should be spent on the elicitation process so as to capture enough real user requirements . If requirements are not clear then methods of elicitation (Such as prototyping ) that helps understand and define the unclear requirements need to be used . Intensive user-developer interaction is necessary to best define and understand user requirementsRequirements case study2Requirements elicitation for Hp /AgileStakeholdersThe essence was to develop an employee safety and health training system to training employees on health and safety (EHS ) coursesHewlett-Packard high voltage equipments which performed manufacturing employees of the company whose health and safety was at stake , the employee , EHS administrator and the 3 bay area company locationsChallengesThe data was a lot and it was managed on central system . Managing this data was difficult . There was a need to : cart track employee supervisor and job , indicate employee job course of EHS to be taken , the course each employee had taken and the due date for each employee , track classes , enrollment and class performance for each employee , communication between the EHS administrator and other business managers and a need for report generationRequirements elicitation processThe developers were the Andre Gous and Jamie Parker . They used interviewing technique to get a clear understanding of different users and their working environmentComplex Data flow diagrams were used to model the data flows . Peer reviews were also used to validate and specify requirements . Data flows were also used to derive how conceptual components would evolve to database structuresOutcomeThe users loved the safe- to- train EHS system and the administrator was congratulated by management for a good job . The system was a high quality productLessonIt is good to understand users and their working environment before starting to gather requirements . Interviewing technique is good for this purposeData flow diagramming is very effective for describing and communicating data flows into a systemRequirements modelling and AnalysisThis step commences once user requirements have been gatheredModeling is a fundamental activitity in requirements development process that entails construction of requirements abstract s that are subject to tame interpretation through validation and verification (Al-Ani , B , 2003Modeling techniquies are also used in the elicitation step where the models help prompt for more requirements gathering (P . Coad , E . Yourdon 1991Approaches of requirements modelling areEnterprise modellingThis kind of modelling entails an understanding of the structure of the organisation (rules governing organisations business operation goals and objectives of organisations , roles of organisation members and information needed , generated by and manipulated by the organisation The technique derives the system purpose from organisation behavior in which the system will operate . The behaviour is described in terms of business goals /objectives and the tasks resources used in business operation . A model can also describe anorganisation in respect to its rules and regulations , workflows and services provided . User and business requirements are refined through modeling that brings requirements that can be operationalised (Abadi , C , A . Bahill , 2002Data modelingComputer systems especially large information systems usually generate and use large amounts of information , which requires anunderstanding so that it can be manipulated and managed effectivelyData modeling entails identifying data that is to be used by a proposed system and how that data conforms to real world problems that the system is move to solveEntity - Retionship (E-R ) model is used for data modeling andfanalysis but it is be by the currently increasing intensive use of object - oriented modeling that uses classes and objects and their hierarchies (P . Coad E . Yourdon , 1991Behavioural modelingInvolves modeling existing and desired functional behaviour of systems and stakeholders . The first step is to model how current system operates and crumble it to determine the essential functionality and develop models from the information to demonstrate how the proposed system must behave (Michael Jackson , 1995 . The modeling methods provide different precitsion levels and are subject to different analysis approaches Methods range from structured to object - oriented and from soft to formal methodsDomain modelingDomain models provide abstraction of the physical world the proposed system is required to operate (Acharya , S , et al , 2005 Explicit domain models stick out a detailed thinking of what is perceived about domain and also provides requirements re-use advantage within a domain of same kind (Finkelstein , A , 1988Non - Functional requirements modelingThese are functions associated to quality ( such as performance learnability , and safety functions . These functions are difficult to analyse due to their difficult to measurement . They denote system properties and are therefore not related to individual modulesRequirement models analysisModels are graphical representations and in consequence provide an easy way and opportunity of analysing them , a picture speeks more than a thousand talking to Graphical representation of a system behaviour or property is easy to interprate and analyse since they are easily understoodAnalysis techniques include : requirements animation , automated reasoning (such as analogical and case - based reasoning , consistency checking (such as checking models , verification and validation techniques (such as reviews inspections and structured walkthroughsRequirements specificationFollows requirements analysis stage and it entails documenting the requirements in an unambigous , clear , precise and correct terms Requirements are scoped so as to satisfy stakeholders vision (Alan M Davis ,1992Specification also involves communicating the requirements to the different stakeholders . Document writing involves ensuring that they can be read , analyzed , rewriten (incases of changes ) and validated easily and with ease . Different language notations have different expressions and reasoning to the stakeholders of the system (Al-Ani , B , 2003The deliverable of specification st
