Efw - A Prototype Engineering Framework with Graph-based Tool Agents

What is a Framework?

"... an infrastructure of software and interfaces that enable the integration and interoperability of [engineering] systems" - CFI FAQ

One answer to the question:

"How do we connect people, their models, and their tools?" Olsen [1994]

( from Survey of Engineering Framework Technology, [Peak, 1996] )

Example Framework Objects

- Represent the computing infrastructure of a group or company.

- Enables interaction of "people, their models, and their tools"

Users
Models (e.g., FEA SMMs)
Machines - object wrapper around actual computer.
Tools
Agents
Framework

Typical Analysis Process (e.g., Finite Element Analysis)

Tool Agents

Support highly automated analysis:

Take inputs from SMMs.
Provide input and control files to solution tools.
Run each tool.
Give results back to SMMs.

Agent Plans

Agent "work flow diagram" defining connections between client, data items, and tool runs.

Typical Plan

Data Item - Abstracted representation of tool inputs and outputs.
Handles transfers between client and tool runs
Manages and OS files and networking.
Tool Run - Indicates usage of a tool.
Manages tool execution.

Examples

Cadas SMM - Plan with FEX/Solver

Example Plan Instance (usage of a plan)

Agent Plans and Graph Theory

An agent plan is a type of directed acyclic graph (dag)

where vertices are:

data items, tool runs, and the client

and edges are:

data item usage links and creation links.

Graph Theory Benefits

Can define terms and properties more precisely.
Ex. See Tool Plan Capabilities & Limitations.
Ex. Proposition: A tool agent can get results for any processable tool plan. (not proven yet)
Can utilize existing graph algorithms and operations.
Ex. Determine all direct and indirect inputs to tool run #2.

Observations

Characteristics of Computing Environment

(e.g., experiences at AT&T Bell Labs, Hitachi, and Georgia Tech)

Highly dynamic (e.g., tool version changes)
Not well-defined.
Present tools are not framework-oriented (but usually ok).

Characteristics of Prototype Framework: Efw

Simplified version of work by CFI, NIIIP, etc. [ Peak, 1996 ]
Based on File-Oriented Tool-Tool Interaction
- Good for low tool-tool interaction applications.
- Typically possible with most existing tools.
- Primary choice for existing traditional tools.
- Tool encapsulation process: some methodology, some "art"
Other Type of Tool-Tool Interaction: Programmable Interfaces
- Example: SDRC Open Architecture
- Good for highly interactive tool-tool applications.
- Tool encapsulation process: defined methodology

Benefits

Fast, highly automated analysis.
Repeatable, well-defined analysis tool process.
Reduce tedious, error-prone manual tasks.

Costs - "There's no free lunch!"

Maintenance of framework data: changes in people, tools, machines, etc.
Development effort to produce framework-compatible tools.

Summary - Efw Framework and Agents

Demonstrates simple, yet useful, framework technology via graph-based tool agents.
Provides basic framework needs of MRA.
Potential Usage: A framework tool for company applications.
- Use with or without the MRA.
- Other tools could control Efw, provide inputs, and receive outputs.
Use with other types of tools.
Supports highly automated analysis.