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Re: Race condition...



It seems to me we need to educate the regulators and designers. The key is discontinuous response. To test again by doing much the same thing is no test. Example: random keyboard input to

Become fiery ball? [N,y]

where the N means the default answer is "no". That means you have to have a y followed by an Enter to get a fiery ball, which is about a 1 in 6000 chance on an 80-key keyboard. So the retest is unlikely to reproduce the error, but it will kill a lot of people among millions of users.

Once they understand this, the question becomes how to design a continuous response with no exceptions. Answer: not any of the ways that have become standard in the last 20 years. (I just bought an Arduino and looked at its textbook, "Making Things Talk," to get a naive view of how the world of embedded control is trending, and there are ill-defined abstracted layers everywhere.)

Larry Dickson

On Mar 15, 2010, at 6:09 AM, Bob Gustafson wrote:

> Just needs a dose of Formal Methods..
> 
> and/or Model Checking..
> 
> More at http://en.wikipedia.org/wiki/Formal_methods
> 
> Bob G
> 
> On Mon, 2010-03-15 at 08:52 -0400, Marc L. Smith wrote:
>> ...of one kind--or another!    ;-)
>> 
>> Prius Incident Stumps Investigators
>> By REUTERS
>> Published: March 15, 2010
>> http://www.nytimes.com/reuters/2010/03/15/business/business-us-toyota-prius-investigation.html?_r=1&hp
>> 
>> 
>> 
>> 
>> 
>> 
> 
>