[comp.software-eng] CASE - Computer Aided SYSTEMS Engineering

jmi@dac.mdcbbs.com ((JM Ivler) MDC - Douglas Aircraft, Long Beach, CA) (06/13/90)

In article <20147@duke.cs.duke.edu>, crm@romeo.cs.duke.edu (Charlie Martin) 
writes:
> In article <5190@stpstn.UUCP> cox@stpstn.UUCP (Brad Cox) writes:
>>The trouble with Computer Aided Software Engineering is that it presumes
>>the existence of such a thing as Software Engineering.
>>
> 
> Well SAID, Brad!

I have a problem here. Everyone who has posted on this topic has defined CASE 
to be Computer Aided SOFTWARE Engineering. I have to agree that "software 
engineering" is a bit of a falicy. What we are really dealing with is SYSTEMS 
engineering.

When I get called in on a project I am not a "software" analyst, but a 
"systems" analyst (that's what it says on my business card :-) ). I don't think 
about how to solve the problems with software, but I look at the systems that 
are being used and try to seek systems oriented solutions. My job doesn't 
require a computer, it requires a mind that is capable of viewing all the 
alternatives to performing a process or series of processes.

To do this I use a tool, called a computer, to perform in the most efficient 
manner. I also like tools that help me (CASE tools) to clearly see the 
relationships of individuals and tasks, processes and data, functions and 
decision structures. Before CASE tools were around this was done on paper 
using plastic templates [remember flowcharts?]. Now we have the tools on the 
computer that help us define SYSTEMS and help us check the work.

I'm not saying that these tools are "the end" any more than I felt that I was 
satisfied with that plastic template. They are just tools. I hope that they 
will get better, and thereby allow me to perform my work more efficiently, but 
I don't knock anything that *helps* me do my job better.

How do these tools help me most? They let me understand and map complex systems 
and complex relationships in a manner that I can discuss the systems and the 
relationships with a variety of users. Determinations can be made on 
modifications to the systems and the processes that make up the systems to make 
them more efficient and then, if all parties want, this "map" of the system, 
can be passed over to a designer who will take the "map" and develop a method 
for taking the mapped system and developing software to support it.

Sometimes the systems are not put on the computer, but are run by processing 
paper. That is the choice of my customer. I only help them define the best 
possible system using the tools available. One of these tools is the computer, 
another is a drawing tool to build the "maps" and wouldn't it be nice if that 
tool also did some of the gruntwork and checked the validity of the system 
designed? 

I'm not knocking OOA and OOD. I don't have any real experience with them. When 
I used a plastic template I didn't knock computer drawing tools and drawing 
checkers that enforced top-down structured analysis and design, I just used 
them when they became available to perform my job. They made my job easier, so 
I use them.

As an example: A man knocks a wood peg in to hold up a beam with a rock. He is 
offered a wood mallet and he uses it because it suites his needs. Now he is 
given an iorn nail to put in the beam. The mallet is no longer doing the job, 
he goes back to the rock until someone gives him a steel hammer. It isn't the 
tools that are bad, they just have to be the right tools to do the right job.

CASE - Computer Aided Systems Engineering.

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