The analysis steps. Problem Analysis Sub-problem 3 Sub-problem 2 Sub-problem nSub-problem 1

The process of analysis. Solution Solution 3 Solution 4 Solution 2 Solution 1 Proposed solution types…..

The relationship between computer science and software engineering Computer ScienceCustomer Theories Computer Functions Problem Type Software Engineering Tools and Techniques to Solve Problem

How human error causes a failure. Human ErrorFaultFailure can lead to

McCall’s quality model. Correctness Reliability Efficiency Integrity Usability Maintainability Testability Flexibility Portability Reusability Interoperability Traceability Completeness Consistency Accuracy Error Tolerance Execution Efficiency Storage efficiency Access control Access audit Operability Training Communicativeness Simplicity Conciseness Instrumentation Self-descriptiveness Expandability Generality Modularity Software System Independence Machine Independence Communications commonality Data commonality

CUSTOMER Sponsors system development USER Uses system PROGRAMMER Builds system Contractual obligation Software system Needs Participants in software development.

System definition of paycheck production. System boundary Computer Mail room Date validation Calculation Pay checks Printing Pay information

Layers of a water-monitoring system. Remote data collection system Reporting system for data Calculation system for remote data Communication system from remote sites to central Data management system for collected data

The roles of the development team Maintenance System Design Requirements Analysis and Definition Program Design Program Implementation Unit Testing Integration Testing System Testing System Delivery SOFTWARE DEVELOPMENT STEPS DEVELOPER ROLES ANALYST DESIGNER PROGRAMMER TESTER TRAINER

The key factors that have changed software development Time to market Shifts in economics Desktop computing Networking Object technology Problems with waterfall User interfaces CHANGES IN SOFTWARE ENGINEERING

Electrical device Sensor Water sensorAir sensor Simple Hierarchy for monitoring equipment Example

Differences in development (Wasserman 1996). Controlled development Rapid application development Mission-critical Multiuser Multiplatform 2- to 3-tier development Limited scope/vision Low/medium risk Single/multiplatform 1- to 2-tier development Packages/minimal development Lowcost/low risk Single platform Single-user, desktop productivity tools Departmental applications Enterprise- or division-wide applications

Using measurement to fid a solution Real, Empirical WorldFormal, Mathematical World Empirical relational system Formal relational system Empirical relevant results Numeric Results Implementation of solution Interpretation Measurement Mathematics, statistics

Piccadilly Television franchise area. Example

Figure1.17 Piccadilly context diagram showing system boundary. (Robertson and Robertson). Piccadilly Television Airtime Sales Production Companies Piccadilly Management Broadcasting Board Program Suppliers Suggested Campaign New Program Television Ratings Report Program Purchase Agreement Agreed Campaign Advertising Agencies Selected Spots Spot Upgrade Request Campaign Requirements Copy Transmission Instructions Program Transmission Schedule Agency Invoice Ratecard Preemption Warning Commercial Copy Recording Sales Target Instructions Revenue Reports Program Transmission Schedule Programming Rules Audience Measurement Bureaus Upgrade confirmation