model based methods for systems engineering l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Model Based Methods for Systems Engineering PowerPoint Presentation
Download Presentation
Model Based Methods for Systems Engineering

Loading in 2 Seconds...

play fullscreen
1 / 42

Model Based Methods for Systems Engineering - PowerPoint PPT Presentation


  • 83 Views
  • Uploaded on

Model Based Methods for Systems Engineering. Presentation to SC SPIN 24 September 2009 Professor C.E. Dickerson. Vertical Industry Architecture. Horizontal Industry Structure. The Vertical Computer Industry – Circa 1980. The Horizontal Computer Industry – Circa 1996. Sales and distribution.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

Model Based Methods for Systems Engineering


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
model based methods for systems engineering

Model Based Methods for Systems Engineering

Presentation to SC SPIN

24 September 2009

Professor C.E. Dickerson

computer business architecture evolution 1980 2000

Vertical Industry Architecture

Horizontal Industry Structure

The Vertical Computer Industry – Circa 1980

The Horizontal Computer Industry – Circa 1996

Sales and distribution

Sales and distribution

Retail Stores

Superstores

Dealers

Dealers

Application software

Application software

Word Perfect

Word

Etc.

Operating system

Operating system

UNIX

DOS and Windows

OS2

MAC

Computer

Computer

Compaq

Dell

Packard Bell

IBM

Etc.

Chips

Chips

Intel Architecture

Motorola

RISCs

IBM

DEC

Wang

Sperry

Univac

Computer Business Architecture* Evolution: 1980 - 2000

Will Systems Engineering undergo these types of changes?

*Source: Dr. James C. Stoffel, INCOSE Keynote Address, 12 July 2005: “Systems Engineering-An Imperative for Economic Growth”

Dr. Stoffel proprietary material; used with permission.

agenda
Agenda
  • Modeling Languages
    • UML
    • SysML
  • A Quick Look at Systems Engineering
  • Model Driven Architecture (MDA)
  • MDA for Systems Engineering
key types of uml diagrams for modelling systems
Use case

Class

Packages

Object

Sequence

Collaboration

State Chart

Activity

Component

Deployment

Key Types of UML Diagramsfor Modelling Systems

This module of the course will focus on the left hand five types of diagrams.

use case diagrams
Use Case Diagrams
  • Show the interactions between a system and the users or other external systems.
  • The emphasis is on what the system does rather than how it does it.
  • The viewpoint is that of an external observer.
  • Use case diagrams should not be confused with scenarios which are examples of interactions but
    • The collection of scenarios for a use case may suggest a suite of test cases.
  • Use cases are part of requirements engineering.
    • Any aspect of system behaviour that provides a measurable result should be captured in a use case.
    • They should be a means of communication.
description of use case diagrams

Information Management System

Create New Account

System Administrator

Description of Use Case Diagrams

Graphical Elements

Use cases (Ovals)

Actors (Stick figures)

Communication (Lines)

Boundary (Rectangle)

class diagrams
Class Diagrams
  • Correspond to system definition by showing its classes, which become system objects, and their relationships.
  • The emphasis is on what interacts rather than what happens in the interaction.
  • The viewpoint is internal to the system.
relationships in class diagrams
Relationships in Class Diagrams
  • There are three types of class relationships
    • Association: a relationship between instances (objects) of two classes, a reference to an object in the form on an attribute
    • Aggregation: a stronger form of association in which one class owns but may share a collection of objects of another class
    • Generalization: an inheritance relationship indicating that a class is a type of (i.e. inherits properties from) a superclass
  • A class integrates attributes and behaviours.
description of class diagram

Information Management System

Create New Account

System Administrator

Account

AcctEntry

1

*

creation date

URL

a method

a method

Description of Class Diagram

Use Case

Graphical Elements

Class (Rectangle)

Name

Attributes

Methods

Association (Line)

Aggregation (Diamond, Line)

Generalization (Triangle)

Multiplicity (0,1, 1.. n, 1.. *, *)

Class Diagram

abstract classes
Abstract Classes
  • Are partial declarations of a class, omitting behaviour that may be realized in another class
  • Can be used in generalization to create a generic reusable class that for which all the behaviours cannot be implemented
  • Were used in the logical modelling of sentences
  • The graphic may omit attributes and behaviours
package diagrams
Package Diagrams
  • Are groupings of classes (called packages) that provide structure or organization to the system model
  • The emphasis is on organization of and dependencies between the packages.
    • A dependency between two classes is a declaration that one class needs to know about another class in order to use its objects.
    • The dependency relationship is weaker than association
  • Packages can be defined on the basis of logical relationships, subject matter, or responsibilities.
description of package

Information Management System

Create New Account

Account

Management

System Administrator

AcctEntry

Security

Account

Credentials

IDVerifier

Description of Package

Use Case

Graphical Elements

Package ( Tabbed Rectangle)

Name

Classes Contained

Dependency (Dashed Arrow)

Hierarchy (Nested; or ::)

Package Diagram

object diagrams

entry

AcctEntry

entry: AcctEntry

URL

a method

Object Diagrams
  • Objects are instances of Classes
    • Classes are blueprints for objects.
  • Notation is similar to classes
    • Object names are underlined
    • Colons are used in association with the instantiated class

Objects (are)

instances of a

Class

sequence diagrams
Sequence Diagrams
  • Unlike the static views presented by class and object diagrams, interaction diagrams are dynamic views that show how objects collaborate by means of interactions.
  • A sequence diagram is an interaction diagram that shows
    • The details of how operations are carried out
    • What messages are sent and when
  • The emphasis is on the order of interactions between parts of the system.
    • It should not be confused with timing.
description of sequence diagrams

Use Case

Information Management System

: Information Management

System

Create New Account

admin: Administrator

Request new account

System Administrator

Select account type

Enter author details

Reply

Description of Sequence Diagrams

Graphical Elements

Participants* (Rectangles)

Time (Dashed line, down)

Activation (Thin Rectangles)

Events (Annotated Arrow)

*These are the parts of the system and often are represented as objects.

systems modelling language sysml
Systems Modelling Language (SysML)
  • What is SysML?
    • A visual (graphical) modelling language that extends UML
    • It provides semantics and notation for systems engineering
  • SysML supports
    • The specification, analysis, design, verification and validation of systems that include hardware, software, data, parametrics, personnel, procedures, and facilities
    • Model and data interchange via the XMI and AP233
  • SysML is being implemented in tools provided by the major and smaller vendors (IBM, Telelogic, No Magic, Sparx …)
    • And is part of the OMG UPDM* specification

*the UML Profile for the DoDAF and MODAF architecture frameworks

relation of uml and sysml
Relation of UML and SysML

Source: the OMG SysML Resource Page, 11 February 2008

sysml diagram types
SysML Diagram Types

Source: the OMG SysML Resource Page, 11 February 2008

the four pillars of sysml
The Four Pillars of SysML

Source: the OMG SysML Resource Page, 11 February 2008

agenda20
Agenda
  • Modeling Languages
    • UML
    • SysML
  • A Quick Look at Systems Engineering
  • Model Driven Architecture (MDA)
  • MDA for Systems Engineering
definitions of systems engineering
Definitions of Systems Engineering
  • An interdisciplinary approach encompassing the entire technical effort to evolve and verify an Integrated and life-cycle balanced set of system people, product and process solutions that satisfy customer needs. Systems engineering encompasses:
    • The technical efforts related to the development, manufacturing, verification, deployment, operations, support, disposal of, and user training for, system products and processes;
    • The definition and management of the system configuration;
    • The translation of the system definition into work breakdown structures; and
    • The development of information for management decision making. (EIA/IS-632-1994)
definitions of systems engineering22
Definitions of Systems Engineering
  • An interdisciplinary collaborative approach to derive, evolve, and verify a life cycle balanced system solution that satisfies customer expectations and meets public acceptability. (IEEE 1220-1994)
  • No definition:
    • ANSI/EIC-632-1998
    • IEEE 1220-1998 and IEEE 1220-2005
    • ISO/IEC 15288
the v model

User requirements, System concept, Validation plan

Validation

Validate System to User Requirements

System Specification an Verification plan

Verification

Integrate System and Verify to Specification

Configuration Item Specification and Verification plan

Verification

Assemble CIs and Verify to Specification

“Built-To” Specification and Verification Procedures

Verification

Inspect/Test to “Build-To” Specification

Integration and Verification

Decomposition and Definition

Fabricate,

Assemble,

Code

Forsberg and Mooz "v" model.

The “V” Model
agenda24
Agenda
  • Modeling Languages
    • UML
    • SysML
  • A Quick Look at Systems Engineering
  • Model Driven Architecture (MDA)
  • MDA for Systems Engineering
the promise of the omg mda
The Promise of the OMG MDA*

*OMG MDA Guide V1.0.1, 12th June 2003.

  • Implementation
    • Integrate, target new infrastructure by existing designs
  • Integration
    • Automate production of data integration bridges
  • Maintenance
    • Design becomes available in machine readable form
  • Testing and simulation
    • Models can be used to generate code to validate requirements, test infrastructure, simulate behaviour

To allow definition of machine readable application and data models which allow long term flexibility of:

omg background
OMG Background
  • OMG (Object Management Group) has been an international, open membership, not-for-profit computer industry consortium since 1989.
  • OMG’s current standards include:
    • UML - Unified Modelling Language, a standardised specification language for object modelling
    • SysML - Systems Modelling Language, a general-purpose graphical modelling language for specifying, analyzing, designing, and verifying complex systems.
    • MOF – Meta Object Facility, is a standard for model-driven engineering, is the mandatory modelling foundation for MDA.
    • MDA - Model Driven Architecture, an approach to using models in software development
what is mda
What is MDA?
  • A significant paradigm shift in software engineering
    • A move from Object Management Architecture to Models
  • A trade marked term from the Object Management Group (OMG), MDA was initiated in late 2000 and has been public since 2001

http://www.omg.org/http://www.omg.org/mda/

  • MDA provides an open, vendor neutral approach to the challenge of business and technology change.
  • Separates business and application logic from underlying platform technology; insulates the core of the application
mda cost savings over program life codagen testimonial to omg

Level of Effort ($)

Region of

Cost Savings

Program Phase

Maintain

Test

Deploy

Requirements

Implementation

Analysis/Design

MDA Cost Savings over Program LifeCodagen Testimonial to OMG

Codagen Testimonial on Development Costs for CGI Program:

w/o MDA $8.073M

with MDA $5.475M

Savings $2.598M (32%)

omg concept of mda
OMG Concept of MDA
  • MDA is an approach to system development.*
  • In MDA, model of a system is

a description or specification of that system and its environment for some certain purpose.

  • The MDA approach is model-driven because

it provides a means for using models to direct the course of understanding, design, construction, development, operation, maintenance, and modification [of a system].

*In the MDA Guide V1.0.1, the discussion focuses mostly on system software.

mda terminology system architecture
MDA Terminology: System Architecture
  • The architecture* of a system is a specification of the parts and connectors of the system and the rules for the interactions of the parts using the connectors.
  • The Model-Driven Architecture prescribes certain kinds of models to be used and
    • How those models may be prepared and
    • The relationships of the different kind of models
  • The Model-Driven Architecture specifies three viewpoints on a system.

*The definition in the MDA Guide V1.0.1 is based on Shaw and Garland, Software Architecture.

mda terminology view and viewpoint
MDA Terminology: View and Viewpoint
  • A viewpoint on a system is a technique for abstraction using a selected set of
    • Architectural concepts and structuring rules
    • To focus on particular concerns within that system.
  • The term abstraction is used to mean the process of suppressing selected detail to establish a simplified model.
  • A viewpoint model or view* of a system is a representation of that system from the perspective of a particular viewpoint.

*The definition in the MDA Guide V1.0.1 is based on IEEE 1471.

mda terminology platform independence
MDA Terminology: Platform, Independence
  • A platform is a set of subsystems and technologies that provide a coherent set of functionality through interfaces and specified usage patterns*.
  • Platform independence is a quality that a model may exhibit, where the model is independent of the features of the platform.

*The definition in the MDA Guide V1.0.1 goes on to require that any application supported by the program can use [the subsystems and technologies] without concern for the details of how the functionality provided by the platform is implemented .

mda terminology viewpoints
MDA Terminology: Viewpoints
  • Computational Independent Viewpoint
    • Focuses on the environment of the system and requirements for the system
    • The details of the structure and processing of the system are hidden or as yet undetermined.
  • Platform Independent Viewpoint
    • Focuses on the operation of a system while hiding the details necessary for a particular platform.
    • Shows that part of the complete specification that does not change from one platform to another.
  • Platform Specific Viewpoint
    • Combines the platform independent viewpoint with an additional focus on the detail of the use of a specific platform.
mda terminology views models
MDA Terminology: Views (Models)
  • Computational Independent Model (CIM)
    • A view of the system from the computation independent viewpoint.
    • Does not show details of the structure of the system.
  • Platform Independent Model (PIM)
    • A view of the system from the platform independent viewpoint.
    • Exhibits a specified degree of platform independence so as to be useful for use with a number of different platforms of similar type.
  • Platform Specific Model (PSM)
    • A view of the system from the platform specific viewpoint.
    • Combines the specifications of the PIM with the details that specify how that system uses a particular type of platform.
terminology system specification
Terminology: System Specification
  • Platform Model (PM)
    • A set of technical concepts, representing the different kinds of parts that make up a platform and the services provided by that platform.
    • Also specifies requirements on the connection and use of the parts of the platform, and the connections of an application to the platform.
    • A generic platform model can amount to the specification of a particular architectural style.
  • Implementation
    • A specification which provides all the information needed to construct a system and to put in into operation.
model transformation
Model Transformation
  • Model transformation is the process of converting one model to another model of the same system.
  • An MDA mapping provides specifications for transformation of a PIM into a PSM for a particular platform.
    • The platform model will determine the nature of the mapping.
  • Model transformation can be thought of as part of the design and development process.

*See for example Model Driven Architecture with Executable UML, Raistrick et al..

system design and model transforms
System Design and Model Transforms
  • System design relates to
    • How one parametric model of a system
    • Is transformed into another model
  • Model transformation
    • Is a mapping of parameters that at a minimum should
    • Preserve relationships between parameters
  • Matrix representations of relational transforms
    • Have precise mathematical formulations that act on the
    • Cells in the square matrix of parametric relationships
mathematical notation for models
Mathematical Notation for Models
  • The matrix of a model will be designated as M (or other underlined capital letter)
    • M = {y1, … ym} denotes the parameters of M
    • R = {(yi , yj ): i, j = 1, …, mR} is a relation on M
      • The relationship (yi , yj ) in R is denoted yiRyj
  • A Relational Model Transformation Q is a mapping of
    • M = {y1, … ym} to N = {x1, … xn} such that
    • If yiRyj and yjQxk and yjQxl then xkSxl , where
    • S is the relation on N (induced by Q)
  • Q maps relationships in M to relationships in N
agenda40
Agenda
  • Modeling Languages
    • UML
    • SysML
  • A Quick Look at Systems Engineering
  • Model Driven Architecture (MDA)
  • MDA for Systems Engineering
mda adapted to the systems engineering v

Validation

Acceptance Tests

Use Cases, Operational Mission Threads

CIM:

Requirements Analysis, System Concept Definition

Verification

Integrate System and Test to Specification

Model Transformation, Open Sequence Diagrams

PIM:

System Specification

Verification

Assemble Components, Test to Specification

PSM:

Architecture Analysis, Component Specification

Package Diagrams, Component Sequence Diagrams

Inspect/Test to “Build-To” Specification

PM:

“Build-To” Specification, Verification Procedures

Verification

Integration and Test

Analysis and Specification

Implementation:

Procure, Fabricate,

Code, Assemble

Adapted from Forsberg and Mooz "vee" model.

MDA adapted to the systems engineering V
summary
Summary
  • Systems Engineering is in a time of change
    • UML and SysML are a strong influence
    • Model based approaches are emerging
    • SysML based MBSE is rapidly evolving
  • Model Driven Architecture offers agility
    • Model transformation as system design
    • Advances in model transformation formalism
    • Adaptation of MDA to Systems Engineering
  • MDA for Systems Engineering and MBSE are promising approaches for the future