Search found 12 matches
- Thu Nov 20, 2003 7:41 am
- Forum: SD Mailing List Archive
- Topic: Manufacturing Control Systems
- Replies: 30
- Views: 65097
Manufacturing Control Systems
Well said, John. I would add that in my experience the boundaries of the economic model reinforces the mental boundaries of the users - either by inference (for those who are aware of the model boundaries) or by implicit acceptance (by those who dont know the model bounds and limits and merely accep...
- Mon Jul 28, 2003 9:10 am
- Forum: SD Mailing List Archive
- Topic: Where are we in the Long waves
- Replies: 12
- Views: 20436
Where are we in the Long waves
Thanks for the comments Bill! I think I would argue that delocalization of manufacturing is potentially approaching a limit. Seems like 2/3 of the non-electronic products I pick up are made in China or India. Somewhere between lower labor costs and productivity many products seem to be as inexpensiv...
- Mon Jul 28, 2003 8:09 am
- Forum: SD Mailing List Archive
- Topic: Where are we in the Long waves
- Replies: 12
- Views: 20436
Where are we in the Long waves
Hi Geoff! When I say I am "comfortable" with an outlook of decline, I intended to indicate that I find decline a very viable scenario - not that I nor the world should view decline as a preferable or attractive future. I personally feel (part systems thinking/part gut) that the US in parti...
- Thu Jul 24, 2003 8:53 am
- Forum: SD Mailing List Archive
- Topic: Where are we in the Long waves
- Replies: 12
- Views: 20436
Where are we in the Long waves
I think you are asking a very important question. I think there is a bit of chicken and egg aspect to the answer that is highly perceptual though and should be recognized up front. I would tend to suggest that productivity is the primary driver combined with corporate globalization, delocalization (...
- Fri Jul 26, 2002 10:17 am
- Forum: SD Mailing List Archive
- Topic: Differential equations
- Replies: 25
- Views: 49153
Differential equations
In his response, Niall compares induced voltage otation of an electric field to velocity. As a ChE I am out of my element with voltage. I am confident I understand the concept of velocity better than voltage, so I began parsing Nialls comments with Velocity. Velocity seems more like an arbitrary pro...
- Thu Jul 18, 2002 10:34 am
- Forum: SD Mailing List Archive
- Topic: Watershed Modeling
- Replies: 3
- Views: 4934
Watershed Modeling
Good question Bill! I would say, no, that it is still not a desirable case for allowing a negative stock... My logic is based on the fact that the dynamics of depleting the water in the pond bed is very different than the dynamics of evaporation, animal drinking, etc. in the above zero state. While ...
- Fri Jul 12, 2002 7:37 am
- Forum: SD Mailing List Archive
- Topic: Representing constraints
- Replies: 30
- Views: 54056
Representing constraints
This is perhaps more semantic than literal, but I would tend to suggest that considering a backlog a negative stock is more a convenience than proper. A unit of backlog does not seem perfectly equivalent to a unit of product. Suppose we define backlog is a positive stock of unfilled orders (or a pos...
- Tue Jun 25, 2002 11:27 am
- Forum: SD Mailing List Archive
- Topic: SD Reviews of A New Kind of Science by Stephen
- Replies: 0
- Views: 4054
SD Reviews of A New Kind of Science by Stephen
Greetings Peter! Unfortunately your link to slashdot seems to be dead so I cant respond directly to what you read, but it seems to have given you an erroneous interpretation of Wolframs book. Wolfram clearly does not suggest that the relatively simple cellular automata (or rules based systems) he es...
- Thu Mar 21, 2002 12:52 pm
- Forum: SD Mailing List Archive
- Topic: On information quality and appropriateness
- Replies: 3
- Views: 8626
On information quality and appropriateness
Hi Jim! My immediate response to your list is that, in contradiction to Prof. Forresters suggestion of not viewing his list of elements as "desirable" or "undesirable", you selected scales for these words which frequently carry clear positive and/or negative connotation. Your cho...
- Thu Mar 21, 2002 11:39 am
- Forum: SD Mailing List Archive
- Topic: SD Models from Written Text
- Replies: 30
- Views: 39088
SD Models from Written Text
I agree that a model from text process or program would be quite useful. My facilitation experience leads me to focus on three serious hurdles to success in generating meaningful models from text. These hurdles suggest to me that a model parser would only be useful for suggesting preliminary models ...
- Tue Mar 19, 2002 10:17 pm
- Forum: SD Mailing List Archive
- Topic: SD Models from Written Text???
- Replies: 2
- Views: 4319
SD Models from Written Text???
Two observations seem pertinent. 1) There is a difference between deriving a model from text and developing a model in an interview process. This thread started (as I recall) with George Richardson suggesting that it would be interesting to have expert modelers take the same information (text) and o...
- Mon Dec 10, 2001 9:54 am
- Forum: SD Mailing List Archive
- Topic: A causes B
- Replies: 14
- Views: 33283
A causes B
Hi Alex! Philosophers have long suggested that humans perceptions of "cause and effect" are effectively incomplete and not necessarily reflective of reality. In quantum physics we see this phenomenon clearly, where perspective, tools, and paradigms dictate the nature of the perceived reali...