Enterprise Systems Modeling EGN 5623 Enterprise Systems Optimization Fall, 2012

1. Enterprise Systems ModelingEGN 5623 Enterprise Systems OptimizationFall, 2012

2. IDEF • IDEF0 (activities) • IDEF1x (information) • IDEF2x (dynamics) • OMT • Functional model • Object model • Dynamic model Information systems modeling tools

3. IDEF (ICAM Definition) • Developed by the US Air Force Integrated Computer Aided Manufacturing (ICAM) Programs in 1981 • ICAM Objective • To develop structured methods for applying computer technology to manufacturing and to better understand how best to improve manufacturing productivity IDEF Concept (1)

4. IDEF0 • An activity model of a manufacturing system and environment • IDEF1 • An informational model of the system and environment • IDEF2 • A dynamic model to describe time-varying system behavior IDEF Concept (2)

5. IDEF Methodology • Modeling process and tools, leading to creation of the three IDEF models • IDEF0 (activities) • IDEF1x (information) • IDEF2x (dynamics) • Commercial IDEF software tools • Design/IDEF by Meta Software Company • AI0WIN by Knowledge Based Systems Inc. IDEF Concept (3)

6. Object modeling technique (OMT) • “Object-oriented” means: • Software organized as a collection of discrete objects that incorporate both data structure and behavior, in contrast to conventional programming in which data structure and behavior are only loosely connected. • OMT Methodology (in stages): • system analysis, • system design, • Object (implementation) design, and • implementation. OMT Concepts (1)

7. Synergy (i.e., shifting focus from coding technique to packaging, based on consistent • identity, • classification, • polymorphism, and • inheritance • Abstraction, • Encapsulation, • Combining data and behavior, • Sharing (inheritance of data structure & behavior among subclasses) • Emphasis on object structure (not procedure structure), OMT concepts (2) - common themes

8. Identity • Data is quantized into discrete, distinguishable entities called objects • Classification • Objects with the same data structure (attributes) and behavior (operations) are grouped into a class • An operation is an action or transformation that an object performs or is subject to. • polymorphism • The same operation may behave differently on different classes. • A specific implementation of an operation by a certain class is called a method. Each operation may have multiple methods implementing it. • inheritance • The sharing of attributes and operations among a hierarchy of object classes OMT Concepts (3)- Synergy

9. 3 OMT models used to describe a system: • Object model • describing the objects in the system and their relationships; • Dynamic model • describing the interactions among objects in the system; and • Functional model • describing the data transformation of the system. • Their relationship • The object model describes what changes (or transforms) before when (dynamic model) or how (functional model) it changes. OMT Models (4)

10. It describes the data value transformations within a system. • The functional model contains data flow diagrams. • A data flow diagram is a graph whose nodes are processes (activities) and whose arcs are data flows. OMT Functional Model (5)

11. It describes the static structure of the objects in a system and their relationships. • The object model contains object diagrams. • An object diagram is a graph whose nodes are object classes and whose arcs are relationships among classes. OMT Object Model (6)

12. It describes the aspects of a system that change over time and is used to specify and implement the control aspects of a system. • The dynamic model contains state diagrams. • A state diagram is a graph whose nodes are states and whose arcs are transitions between states caused by events. OMT Dynamic Model (7)

13. IDEF0/functional model • The input to an activity is usually through a user interface for data entry • The output from an activity is usually a user interface for a report, though the output may be a write/update to a database. IDEF0’s • ICOM • Material is an input object. • Product/process data are output objects. • Rules/regulations and SOPs are constraints. Technical precedence is a constraint • Resources/tools and methods are a mechanism. • IDEF1/object model • The collection of the ICOM of an IDEF activity model constitutes an inclusive foundation for the object model. • IDEF2/dynamics model • Each object requires a state diagram to define/govern its life-cycle behavior. • A triggering event is associated with each transition from one state to another. One state may transform to multiple states, depending on the triggering event. Relationship between the two techniques & among the three models

14. IDEF0/functional model • The input to an activity is usually a user interface for data entry • The output to an activity is usually a user interface for a report, though the output may be a write/update to a database. • ICOM • Material is an input object. • Product/process data are output objects. • Rules/regulations and SOPs are constraints. • Resources/tools and methods are mechanisms. • IDEF1/object model • The collection of the ICOM of an IDEF activity model constitutes an inclusive foundation for the object model. • IDEF2/dynamics model • Each object requires a state diagram to define/govern its life-cycle behavior. • A triggering event is associated with each transition from one state to another. One state may transform to multiple states, depending on the triggering event. Relationship between the two methods and among the three models