Page ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 1II. Conceptual ModelingModels in EngineeringModels in EngineeringWhy not English?Why not English?What is Conceptual Modeling?What is Conceptual Modeling?OriginsOriginsInformation Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 2Engineering Software Models in Engineering (Civil, Electrical, Mechanical,Computer,…) Models need to be understandable by engineersand end users (e.g., blueprints) What are appropriate models for software?Conceptual Models!Page ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 3Why not English?Why not English? This is clause 4 from the UN Security Council resolution1441: [on Iraq]"Decides that false statements or omissions in thedeclarations submitted by Iraq pursuant to this resolutionand failure by Iraq at any time to comply with, andcooperate fully in the implementation of this resolutionshall constitute a further material breach of Iraq'sobligations and will be reported to the Council…” The US apparently interpreted this as meaning a materialbreach occurs if the declaration submitted by Iraq containsany false statements. Other security council membersinterpreted it as meaning the breach only occurs if Iraqalso does not cooperate with the inspection process.Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 4What’s the Problem? The clause has the following logical structure:(A or B and C and D) entails E whereA = false statements…B = omissions in the declarations…C = failure to complyD = failure to cooperateE = a further material breach of Iraq's obligations So the two proposed readings are as follows:((A or (B and C and D)) entails E -- US((A or B) and (C and D)) entails E -- othersPage ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 5Computer SystemBusiness ProcessOrderItemShip viaConceptual Modeling ismodeling using a standardizedgraphical notationWhat is Conceptual Modeling?What is Conceptual Modeling?Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 6OriginsSemantic networksSemantic networks in order to model the structure ofhuman memory (Ross Quilian, 1966)SimulaSimula, an extension of ALGOL 60, for simulationapplications that require “world modeling” (Ole-JohanDahl, 1967)Seemantic modelmantic model (Jean-Robert Abrial, 1974), followedby the Entity-Relationship modelEntity-Relationship model (Peter Chen, 1975)as advances over the relational data model.Structured Analysis and Design TechniqueStructured Analysis and Design Technique (SADTSADT)as a “language for communicating ideas” (Douglas Ross,1977)Page ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 7Semantic NetworksAnimalAnimalBird Bird - can fly- can flyFish Fish - can swim- can swimMammalMammalPenguin Penguin - can- can’’t flyt flySharkSharkHumanHumaneatsFeatherFeatherhasisaisaisaisaisaInformation Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 8Simula (1967)personheightweightcoorscustomerhaircutPeriodhaircutPriceenterQueuepayBillnewC, delCpersonheightweightcoorsbarberShopqueuebarbersserveCustomergetPaymentnewBS, delBSpersonheightweightcoorsbarberhaircutTimesalarygiveHaircutnewB, DelBPage ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 9The Entity-Relationship ModelCustomerCustomerM1Places/PlacedByMMContains/isContainedBookBookOrderOrderCustomers placeorders; each ordercontains many booksInformation Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 10Structured Analysis and DesignTechniqueBuySuppliesCultivateExtractSeedsSeed & Vegie PricesPlan & BudgetWeatherPlanBudgetFertilizerSeedsPlantsVegetablesPickProduceVegetablesGrow VegetablesMoneyPage ‹#›Information Systems Analysis and Design csc3402004 John Mylopoulos and Steve EasterbrookConceptual Modeling -- 11Where Do We Start? We learn first how to model things, processes andgoals. Things -- objects, entities,… Processes -- actions, happenings, … see alsobusiness processes Goals -- intentions, wishes,
View Full Document
Unlocking...