Systems Engineering
CORE® - A Model Based Approach
January, 2004
Jody H. Fluhr
Vitech Corporation
www.vitechcorp.com
jfluhr@vitechcorp.com
502.995.8895
1
 Providers of Systems Engineering Solutions
– Consulting
– Training
– Systems Engineering Technology and Tools
• Developers of the CORE Systems Engineering Tool Suite
 Founded in August 1992
 First commercial shipment of CORE in March
1993
 Headquarters in Tysons Corner, Virginia
 US Sales Offices throughout the US
 International Resellers around the world
2
Over 250 Clients in 14 Countries
 DoD
– US Army, US Air Force, US
Navy, USMC
 Intelligence Agencies
– CIA, NIMA, NSA, NGIC
 Dept. of Energy
– Sandia, Los Alamos, Idaho
Falls, Savannah River, Hanford
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NASA
Lockheed Martin
Boeing
Raytheon
FedEx
MITRE
Booz-Allen & Hamilton
SAIC
Sprint
Bearing Point
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UDLP
Northrop Grumman
Orbital Sciences
Battelle
TRW
TASC
Canadian Defense Research
(DRDC)
General Atomics/Burns and
Roe
NOKIA Telecommunications
Motorola
USAA
De Beers Diamond Mines (SA)
Peugeot/PSA Citroen
Israeli Aircraft Industries
Litton/PRC
3
The Systems Engineering Dilemma: Complexity and Synchronization
Inputs
Needs
And
Requirements
With
Their
Perspective
People
withTools
Specialty
Skills
The
Design
“Design
Team
Churn”
With
Their
and
Processes
Producing
Their
Designs
and
Work Products
Electrical
Engineering
External
Teams
Outputs
Software
Engineering
Operational System
Quality
Engineering
Preliminary
System
Concepts
And
Existing
Interfaces
Systems
Engineering
Safety
Engineering
Supporting
Documentation
Procurement
Test and Verification
Mechanical
Engineering
Manufacturing
4
Major Challenge of Systems Engineering
 Managing the complexity to achieve a harmonious solution.
– Many different types of efforts and information must be successfully
managed/executed to achieve project success
• Engineering Elements (Requirements, Functionality, Architecture, System
Resources, etc.)
• Project Elements (WBS, Activities/Tasks, Products, Reviews, Processes,
Budgets, Schedules, etc.)
• Interconnectivity: Elements are related to and affect one another
 Complexity creates Challenges
– Integration Challenge
• How to keep team efforts integrated?
– Consistency Challenge
• How to keep engineering (information, design, documentation, etc.)
consistent across the board?
– Availability Challenge
• How to keep the latest engineering accessible to the whole team?
• How to prevent engineering/decisions based on obsolete/dated
information?
5
CORE Overview
 CORE – A Systems Engineering Technology
– Developed to support the People who implement the Systems
Engineering Methodology
• Analyze, Decompose and Allocate System Requirements
– Validate Requirements
– Requirements Management  Requirements Engineering
• Define System Behavior
– Functionality
– Operations
• Define System Architecture
– Internal and External Interfaces
– Subsystems/Assemblies/Components
• Define System Verification and Validation
– Verification Requirements
– Verification Planning (Events and Resources)
– Designed to meet the Systems Engineer’s Challenges
6
System Engineering Process
Behavior Domain
Source Requirements Domain
Originating requirements
trace to behavior
verified by
CORE
Repository
V&V Domain
Behavior is allocated to
physical components
Architecture Domain
verified by
verified by
Originating requirements
trace to physical components
7
An Iterative System Engineering Process
Primary Concurrent Engineering Activities At Each Layer
Originating
Requirements
Analysis
Source
Documents
Behavior
Analysis
Synthesis/
Architecture
Layer 1
(Draft 1)
System Design Database
Specification & Report Generation
Iterate as Required
When Layer Completed
Synthesis/
Architecture
Behavior
Analysis
Initial Requirements
for this layer are
embodied in the
model passed from
the prior layer
Design
V&V
Layer 2
(Draft 2)
and
and
System Design Database
Specification & Report Generation
Iterate as Required
Initial Requirements
for this layer are
embodied in the
model passed from
the prior layer
Design
V&V
When Layer Completed
Synthesis/
Architecture
Behavior
Analysis
no
7
Accept Handover
From Prior Shift
LP
Design
V&V
Process Claim
Quiting time?
OR
yes
System Design Database
Handover to Next
Shift
LP
Leave Workplace
LE
Layer n
(Final
Specs)
Specification & Report Generation
CORE supports a disciplined, iterative approach to
systems definition.
8
CORE Overview - System Engineering
Capabilities
Requirements Analysis and Management
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Requirements Capture
Requirements Analysis
Requirements Traceability
Requirements Issues and Risks
Design and Implementation
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Physical Architectural Modeling
Functional Modeling
Operational Scenarios
Interfaces – External and Internal
System Integration
System Issues and Risks
CORE
Repository
Verification and Validation
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Verification Requirements Development
Verification Planning and Status
Test Procedure Development
Test Configuration Development
Verification Issues and Risks
Document Generation
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
System Specifications
Interface Control Documents
RFP Responses and Proposals
Requirements Traceability Reports
9
CORE Overview – The CORE Repository
CORE
Repository
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Centralized repository or
database
Accessible to engineering
team
Comprised of classes of
elements and elements
themselves
Elements have attributes
Elements can have
relationships with other
elements
Data in repository can be
viewed and manipulated in
various ways
Database Editor
10
CORE Overview – The CORE Repository
Element
Systems
Engineering
CLASSES

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
Document
System
Components
Functions
Interfaces
Constraints
Requirements
Risks
Issues
Etc.
Relationships
Attributes
This ‘Database Editor’ view allows browsing of all system elements,
Relationships, and attributes.
11
CORE Overview – Engineering Element Example
Element Name
Other Element
Attributes
This element, “ATC Draft
Specs-7.23.90”, documents
these six requirement
elements.
Element
Relationships
Element Editor
12
Example: System Requirements Model
ATC.Draft.
Specs-7.23.90
Original
Requirements
Document
documents
1.0
documents
2.0
documents
documents
3.0
documents
4.0
documents
5.0
6.0
Overall ATC
System
Definition
System
Boundary
Mission
Prime Mission
ATC Efficiency
OriginatingR...
OriginatingR...
OriginatingR...
OriginatingR...
OriginatingR...
OriginatingR...
incorporates
incorporates
5.1
incorporates
5.2
incorporates
5.4
5.5
incorporates
5.6
Automated
Support
Aircraft
Separation
Obstruction
Separation
Air Traffic Flow
Information
Dissemination
OriginatingR...
OriginatingR...
OriginatingR...
OriginatingR...
OriginatingR...
generates
Children
(decomposed)
Requirements
incorporates
5.2.CL
Approved
Separation
Aircraft
Separation.CL
Issue
OriginatingR...
Requirements
Traced to
Functionality
traces to
1.2.3
Predict
incursion of
restricted air
space
Function
allocated to
1.1.1
decomposed by
1.2.3.1
ATC
workstations
Detect an
incursion of
restricted
airspace
Component
Function
Functionality
Allocated to
System
components
allocated to
1.1.1
ATC
workstations
Component
Date:
Author:
3/28/2002
Number:
SE 007
Name:
ATC.Draft.Specs-7.23.90
13
CORE Overview - System Engineering
Capabilities
Requirements Analysis and Management
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Requirements Capture
Requirements Analysis
Requirements Traceability
Requirements Issues and Risks
Design and Implementation

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Physical Architectural Modeling
Functional Modeling
Operational Scenarios
Interfaces – External and Internal
System Integration
System Issues and Risks
CORE
Repository
Verification and Validation

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Verification Requirements Development
Verification Planning and Status
Test Procedure Development
Test Configuration Development
Verification Issues and Risks
Document Generation
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
System Specifications
Interface Control Documents
RFP Responses and Proposals
Requirements Traceability Reports
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CORE Overview – Functional/Operational
Modeling
Iterate
Option 1
Process A
F2
IT
F3
IT
F4
OR
OR
No
F6
Option 2
LP
OR
F5
Yes
F1
LP
LE
AND
AND
F9
Replicate
With coordination
Process B
RP
F7
F8
RP
CORE provides Functional Flow Block Diagrams (FFBDs) to
capture system functionality or operations.
Each Function is an element in the Repository.
15
CORE Overview – Functional Interfaces
F1
F5
Stimulus
F1
Stimulus
AND
Response
AND
F5
F2
F2
F3
F4
F3
Enhanced Functional Flow Block Diagram
Response
F4
N2 Diagram
CORE provides Enhanced Functional Flow Block Diagrams
and N2 Diagrams to capture Functional Interfaces.
16
CORE Overview – Functional/Operational
Modeling and Discrete Event Simulation
# customers
F.1
customer
IT
Customer
Arrives
IT
customer
# customers
F.2
Place Order
F.4
service area
IT
AND
AND
Assemble
Order
IT
F.3
Accept Order
food
# customers
F.5
AND
svc. customer
IT
F.6
Take Food
IT
Leave line
AND
customer
and food
# customers
F.8
yes
0.75
Eat
F.7
eating
kill
IT
F.9
OR
Eat In?
Leave
IT
no
0.25
F.12
cook
Cook Burgers
F.10
kitchen
LP
F.11
Wait To Check
Burgers
Check burger
Supply
OR
no cook
LP
System behavior model defines
architecture of simulation model
CORE executes FFBDs in its Discrete Event Simulator allowing
dynamic analysis of functional models and requirements.
17
CORE Overview – System/Architecture
Modeling
0
Simple Air
Traffic Control
System
System
1
1.1
3
Sector
Command
Center
Comm
Component
Component
1.2
1.3
1.4
ADP
Center Support
Personal
Sector
Command
Facility
Component
Component
Component
1.1.1
Local Comm
Component
1.1.2
ATC
workstations
Main Computer
Component
Component
2
See Next Slide.
Sensors
Component
2.1
2.2
EnRoute
Radars
Terminal
Radars
Component
Component
The System Architecture or System Hierarchy view shows the
breakdown of the system.
Date:
Author:
5/28/2002
Number:
0
Engineer 1
Name:
Simple Air Traffic Control System
18
CORE Overview – System/Architecture
Modeling
Attributes of
this system
component.
Relationships to other elements.
A different view of the same element – it’s attributes and
relationships to other elements in the system model.
19
CORE Overview – System Interfaces
Cabin Air Return
Cabin Air Supply
Data (Front Panel) RS-232
Data (Primary)
Data (Secondary)
See Next Slide.
Electrical Bond
External System
Animal Habitat System
Av Air Supply
Av Air Return
The “Open Circle” on
the interface indicates that
the interface connects through
the Top-Level System to a
subsystem.
Power (Front Panel)
Power (Primary)
Power (Secondary)
System
Component
This Interface or Physical Block Diagram is automatically generated
by CORE based on the data in the repository.
20
CORE Overview – System Interfaces
Interface Name
Interface Description
Interface Connectivity
All things that appear on any diagram are elements in the Repository.
21
CORE Overview – System Interfaces
Data (Front Panel) Connector
Data (Primary) Connector
Data (Pri...
Data (Front Panel)...
Component
Component
Data (Secondary)
External System
Data (Secondary) Connector
Component
Component
Environmental Control Subsystem
Data (Secondary) Interface
Main Processor Assembly
Component
Component
CP1 ...
TD -...
T6 -...
T4 -...
T3 -...
Microprocessor Assembly #1
T1 -...
F3 -...
F1 -...
Component
T8 -...
T7 -...
T5 -...
Microprocessor Assembly #2
T2 -...
F4 -...
F2 -...
Component
Date:
Author:
3/7/2002
Number:
Administrator
Name:
Command and Data Handling Subsystem
22
CORE Overview - System Engineering
Capabilities
Requirements Analysis and Management




Requirements Capture
Requirements Analysis
Requirements Traceability
Requirements Issues and Risks
Design and Implementation






Physical Architectural Modeling
Functional Modeling
Operational Scenarios
Interfaces – External and Internal
System Integration
System Issues and Risks
CORE
Repository
Verification and Validation





Verification Requirements Development
Verification Planning and Status
Test Procedure Development
Test Configuration Development
Verification Issues and Risks
Document Generation




System Specifications
Interface Control Documents
RFP Responses and Proposals
Requirements Traceability Reports
23
CORE Overview: Verification & Validation
Planning
Requirement Source
Requirements
Document #1
Document
documents
Source Requirement
Requirement 1
Requirement 2
OriginatingRequi...
OriginatingRequi...
traces to
traces to
generates
Issue 1
Function 1
External Interface 1
Issue
Function
Link
allocated to
Design/Implementation
verified by
Verification Requirement
Subsystem 1
Verification
Requirement 1
Component
VerificationRequi...
satisfied by
Traceability
documents
Verification Event
Verification Event 1
VerificationEvent
defined by
Test Procedure
uses configuration
Test Procedure 1
Test Configuration
1
TestProcedure
TestConfiguration
formed by
formed by
Test Configuration
formed by
formed by
Subsystem 1
External Interface 1
Test Enviroment
Test System
Component
Link
System
System
24
Program and Project Management
Organizational Model
Project X Team
ResponsibleOrga...
consists of
consists of
consists of
Project Group
Systems
Engineering Group
Test Engineering
Group
ResponsibleOrga...
ResponsibleOrga...
ResponsibleOrga...
Work Breakdown Structure
Project X
Project
consists of
consists of
consists of
consists of
includes
includes
WP.1
Fluhr, Jody
Long, David
WP.2
Requirements
Development and
Management
Technical Solution
Plimpton, James Development
Macdonald, Pat
WorkPackage
ResponsibleOrga...
ResponsibleOrga...
ResponsibleOrga...
accomplishes
ResponsibleOrga...
includes
includes
Validation
Verfication
WorkPackage
WorkPackage
includes
accomplishes
Requirements
Management
Task
Task
Work Package 4
Integrated Process
Customer Reviews
Activity
includes
1.1.1
includes
4.1
Requirement Analysis
includes
WP.5
WorkPackage
1.2
Activity
includes
WP.4
Product Development
and Integration
WorkPackage
1.1
Work Package 1
Integrated Process
includes
WP.3
Task
includes
1.1.2
4.1.1
includes
4.1.2
Requirements
Extraction from
Requirements Sources
Requirements
Decomposition
System Requirements
Review
Task
Task
Task
includes
4.1.3
Project Functional Flow Model
Preliminary Design Assembly 1.1
Critical DesignAssembly
Review 1.1 Test
Review
Integration Process
Process
Task
Task
accomplishes
1.1.1
Requirements
Extraction Process
Flow
AND
AND
Subsystem 1
Integration Process
Subsystem 1 Test
Process
Activity
inputs
Requirements Sources
Product
Design
Acceptance
outputs
Assembly 1.2
Integration Process
Individual
Requirements
Product
Ref.
CORE’s Systems Engineering
Methodology and Capabilities
can be applied to project
engineering.
Refer to ECS Case Study
Assembly 1.2 Test
Process
Proceed to Product
Development
AND
AND
Assembly 2.1
Integration Process
Top-Level
Verification
Process
Assembly 2.1 Test
Process
AND
AND
Assembly 2.2
Integration Process
Top-Level
Integration Process
Subsystem 2
Integration Process
Subsystem 2 Test
Process
Assembly 2.2 Test
Process
25
R
CORE Overview - System Engineering
Capabilities
Requirements Analysis and Management




Requirements Capture
Requirements Analysis
Requirements Traceability
Requirements Issues and Risks
Design and Implementation






Physical Architectural Modeling
Functional Modeling
Operational Scenarios
Interfaces – External and Internal
System Integration
System Issues and Risks
CORE
Repository
Verification and Validation





Verification Requirements Development
Verification Planning and Status
Test Procedure Development
Test Configuration Development
Verification Issues and Risks
Document Generation




System Specifications
Interface Control Documents
RFP Responses and Proposals
Requirements Traceability Reports
26
CORE Overview – Document Generation
Number
Name
Description
The Information Management System shall provide
continuous real-time support to the customers and the
collection systems.
traces to
OR.1
Continuous
Support
C.1 Continuous Operation
OR.2.1
Accept Requests The system shall accept information requests from
certified customers.
1 Accept And Format Request
OR.2.2
Retain Inventory The system shall retain an inventory of previously
collected data/products and provide them to users, if
appropriate..
2 Check Product Inventory
OR.2.3
Control Multiple The system shall control multiple collectors and multiple
Collectors
types of collectors.
OR.2.4
Maximum Staff
The system shall be staffed at a maximum of 25 personnel
on any shift
OR.2.5
Provide
Feedback
The system shall provide feedback on the customer's
request within twenty four hours.
5 Notify User Of Estimated Schedule
OR.2.6
Prioritize
Requests
The system shall provide a means of prioritizing the
customer's requests.
3 Prioritize Request
OR.2.7.1
Monitor Self
Performance
The system shall monitor its own performance.
11 Evaluate Products vs. Request
OR.2.7.2
Assess Self
Performance
The system shall assess its own performance.
11 Evaluate Products vs. Request
8 Put Product In Inventory
9 Get Product From Inventory
4 Determine Collector Mix
6 Task Collectors
PI.1 Provide Feedback
12 Report Deficiencies And
Recommendations
The content of documents are automatically generated by CORE
based on the data in the repository.
27
COREscript and API
 Scripting language provided in CORE
– Object Oriented Query Language
– Document/Report Generation
•
•
•
•
•
MS Word compatible (Rich Text Format)
MS Excel compatible
HTML
Text
Over 30 open-source reports (System Specifications, Interface
Specifications, etc.) are provided
– Query and Analysis
 Application Program Interface
– Provides access to Engineering Repository information by
external applications
– Automation of information exchange with applications such as
PDM, DOORS, etc.
28
The Total Process and Synchronization
C .1
Pe rfo rm C u stomer
Fu nc tion s
Source Requirements
Domain
Requirements
trace to
behavior
pro du cts
AN D
Intelligence
Information System
Source Require...
Document
documents
documents
incorporates
OR.1.1
SYS.1
Continuous Support
Intelligence
Information System
OriginatingRequir...
OriginatingRequir...
System
incorporates
OR.1.2
incorporates
OR.1.3
incorporates
OR.1.4
da ta
ta sk in g
Behavior is
allocated to
physical
components
C .2
Pe rfo rm C o llec tor
Fu nc tion s
constrained by
Retain Inventory
Control Multiple
Sensors
Maximum Staff
Continuous
Operation
OriginatingRequir...
OriginatingRequir...
OriginatingRequir...
OriginatingRequir...
Constraint
Behavior
Analysis
causes
I.1
AN D
C.1
Accept Requests
generates
Ope rate In te llig enc e
In fo rmatio n Sy stem
documents
OR.2
Specific
Requirements
Function/
Behavior Domain
req ue sts
0
ORD.1
OR.1
status
R.1
Media of Requests
Staffing Per Shift
Issue
Risk
Date:
August 3, 1996
Author:
Number:
ORD.1
Name:
Intelligence Information System Source Requirements
D ate:
Octob er 27 , 19 97
Au th or:
N umb er:
N ame :
C on te xt (R o ot Func tion For U nivers e)
U .1
System Engineer
Source
Requirement
s Analysis
Sy stem En gine er
Architecture Domain
Architecture
Analysis
C.0
Universe
verified by
External System
built from
Design V & V
C.1
V&V Domain
Resource MIP S
Process
Domain
5
0
Functi on D etect & Ini ti ate Track
Functi on Threat Track
Functi on (W ith E xi ts) D iscrimi na
built from
C.2
built from
SYS.1
Customers
Collectors
Intelligence
Information System
External System
External System
System
Date:
August 4, 1996
Author:
Number:
Name:
C.0
System Engineer
Universe
Functi on R equest Intercept
verified by
Functi on P erform Intercept
Functi on A ssess K i ll
0
10
20
30
40
50
57.0
verified by
Requirements trace to
physical components
29
CORE Deployment Options
Workstation
CORE2net
Enterprise
Collaborative
environment at the
product, project, or
enterprise level
Integrated application
for small teams or onsite modeling/review
Intranet
Internet
Web browser
access enabling
collaboration at the
enterprise level and
beyond
30
Backup
31
CORE Deployment Options – Workstation
 CORE Workstation
– Fully functional, single-user version of CORE
• Self-Contained Database Management System
• Executes on standalone computer workstation
– Databases can be exported and imported
– Operates in conjunction with CORESim Product
• CORESim provides Discrete-Event Simulation capability
– System Requirements
•
•
•
•
Windows 95/98/Me or Windows NT/2000/XP
300 MHz processor or higher
128 MB RAM
80 MB available hard disk space
32
CORE Deployment Options – Enterprise
 CORE Enterprise
– Client-Server Version of CORE
– Provides scalability for project teams
– Provides access to engineering repository from clients on localarea network
– Enterprise Server System Requirements
•
•
•
•
Windows NT/2000/XP (Professional or Server Additions)
10BaseT Network (or better)
128 MB RAM
300 MHz CPU or higher
– Enterprise Client System Requirements
•
•
•
•
•
Windows 95/98/Me or Windows NT/2000/XP
300 MHz processor or higher
128 MB RAM
80 MB disk free space
TCP/IP protocol LAN access to Enterprise Server
33
CORE Deployment Options – COREsim
 COREsim
– Adds Discrete Event Simulation capability to CORE
– Dynamically interprets behavior models (FFBDs)
– Utilized to identify timing, resource utilization and model
inconsistencies
– System Requirements
• No additional resources required
34
CORE Deployment Options – CORE2net Web
Server
 CORE2net Enterprise Web Server
– Allows any workstation with a web browser and internet access
to Engineering Repository on Enterprise Web Server
– Operates in Enterprise Configuration Only
– Requires user name and password (same as Workstation and
Enterprise)
– Web-based html interfaces
• Predefined views and queries
• Customizable html interfaces can be developed and deployed
35
CORE Deployment Options – CORE2net
 CORE2net allows users
to access the CORE
Engineering Repository
on the Enterprise Server
using the Internet
 Provides browsing
capability
 Authorized users can
change element
information
 Execute queries or
generate views (see
next slide)
36
CORE Deployment Options – CORE2net
37
Thank You for Attending.
Jody H. Fluhr
jfluhr@vitechcorp.com
502.995.8895
Vitech Corporation Phone: 703.883.2270
www.vitechcorp.com
38