code@sphinx.uchicago.edu (paul robinson wilson) (06/16/87)
In article <7116@linus.UUCP> sdl@linus.UUCP (Steven D. Litvintchouk) writes: > >We may soon have a need to train several engineers in using >object-oriented techniques for discrete-event simulation and >modelling. (Languages such as Smalltalk-80 and Simula-67 come to >mind.) > >We are therefore interested in finding out if there are any courses, >tutorials, textbooks, etc., that are good introductions to this >subject. (Note what we are looking for is how to do object-oriented >simulation and modelling in Smalltalk or Simula as opposed to software >development. We know of lots of books that teach simulation in >Simscript and GPSS, but not simulation in Smalltalk or Simula; other >than the Blue Book, which barely touches on the subject.) I too am interested in this, and have several other questions as well: 1) What are the emerging o-o standards? Besides Smalltalk, are there any relatively standard languages with significant graphics? (e.g. are there standard graphics in SCOOPS or CommonLOOPS?) 2) Where should I look for a good intro to issues in the design of object-oriented languages, especially simulation languages? (This might include comparing existing languages like C++ and Objective C, with an idea to the relevant tradeoffs.) 3) Where should I look for info on the availability, features and performance of various O-O languages. (e.g. how fast is PARCPlace Smalltalk, is it available?) My interest in these matters is twofold: (a) I have some ideas for the design of a new kind of simulation language and would like to know the worthwhile features of the current ones; and (2), I'm working on a debugger that will eventually be visually interactive. (I would like to be able to write the graphics in a pleasant, reasonably efficient language and maintain portability between various brands of UNIX workstations.) (These graphics may involve significant non-graphics-primitive computation to figure out layouts, using a breadth-first marker-passing scheme. We have to be able to tweak this part to run at least a third or so as fast as C code. We don't mind bypassing the message-passing scheme now and then.) Any information would be greatly appreciated. If I get a good response and people are interested, I'll summarize to the net. Thanks. | Paul R. Wilson ph.: (312) 947-0740 uucp: ...!ihnp4!uicbert!wilson | | Electronic Mind Control* Lab if no answer: ...ihnp4!gargoyle!sphinx!code | | UIC EECS Dept. (M/C 154) arpa: uicbert!wilson@uxc.cso.uiuc.edu | | P.O.Box 4348 Chicago,IL 60680 (* aka Human-Computer Interaction) |
hwe@beta.UUCP (Skip Egdorf) (06/17/87)
Summary:We do Simulation in an O-O environment. In article <1995@sphinx.uchicago.edu>, code@sphinx.uchicago.edu (paul robinson wilson) writes: > In article <7116@linus.UUCP> sdl@linus.UUCP (Steven D. Litvintchouk) writes: > > > >We may soon have a need to train several engineers in using > >object-oriented techniques for discrete-event simulation and > >modelling. (Languages such as Smalltalk-80 and Simula-67 come to > >mind.) > > > >We are therefore interested in finding out if there are any courses, > >tutorials, textbooks, etc., that are good introductions to this > >subject. (Note what we are looking for is how to do object-oriented > >simulation and modelling in Smalltalk or Simula as opposed to software > >development. We know of lots of books that teach simulation in > >Simscript and GPSS, but not simulation in Smalltalk or Simula; other > >than the Blue Book, which barely touches on the subject.) > > I too am interested in this, and have several other questions as well: My group has been doing large discrete-event simulations in an Object-Oriented environment for the last couple of years. The main overhead is that it takes a good simulations person 6-9 months to be trained to use these environments and methodologies. We have a Software Engineering methodology based on Actors that is used for in-house training that we developed precisely because we could find no information on how to develop simulations in this environment. We use Intellecorp's KEE on Symbolics, TI explorer, and (Lately) Sun Workstations. We have found KEE to be an excellent base for such work, with productivity several times that of more conventional environments. The KEE environment, while very rich, is not any sort of standard. I do not believe that a standard exists that encompasses the necessary tools, graphics, etc. required. I think that the field might be ripe for a how-to book on simulation in the Object Oriented environment. The biggest problem is just what environment to describe?? Smalltalk is the closest thing to standard that includes graphics. However, one of the biggest advantages that we have found to the KEE environment is that an "AI" base that includes forward chaining allows us to attack problems that include simulations of the human decision making process. These simulations are just too hard to do in more "classic" environments. Do we write a Smalltalk forward chainer for inclusion in such a book?? Or is there another environment out there that includes O-O, graphics, a super development environment, and "AI" things?? Skip Egdorf hwe@lanl.gov
lomow@calgary.UUCP (06/19/87)
In article <1995@sphinx.uchicago.edu>, code@sphinx.uchicago.edu (paul robinson wilson) writes: > > 2) Where should I look for a good intro to issues in the design of > object-oriented languages, especially simulation languages? > (This might include comparing existing languages like C++ and > Objective C, with an idea to the relevant tradeoffs.) > The best simulation package (object-oriented or otherwise) I have seen is DEMOS; it was written by and is wholely owned by Graham Birtwistle [Dept. of Computer Science, University of Calgary, Calgary, Alberta, Canada]. DEMOS is a general-purpose, object-oriented, discrete-event simulation package written in Simula. It provides an excellent set of modelling concepts and simulation tools (some of which have been incorporated into the Smalltalk simulation package). My opinion is supported by Kreutzer who writes in his 1986 survey text of simulation languages [Kreutzer, W., 1986, System Simulation Programming Styles and Languages, Addison-Wesley International Computer Science Series, p.176] that DEMOS is a very flexible and powerful modelling framework, ... In the author's opinion, it is currently the best tool available for any kind of discrete-event simulation. It can also be customised to give more support for specialized scenarios. The design rationale for DEMOS is described in the following sources: Birtwistle, G.M., 1979, DEMOS - A System for Discrete Event Modelling On Simula, MacMillan. Birtwistle, G.M., Lomow, G.A., Unger, B.W., Luker, P., 1984a, Process Style Packages For Discrete Event Modelling: Data Structures and Packages in Simula, Transactions of the Society for Computer Simulation, 1, 1, May, 61-82. Birtwistle, G.M., Lomow, G.A., Unger, B.W., Luker, P., 1984b, Process Style Packages For Discrete Event Modelling: Using Simula's Class Simulation, Transactions of the Society for Computer Simulation, 1, 2, 175-195. Birtwistle, G.M., Lomow, G.A., Unger, B.W., Luker, P., 1985, Process Style Packages For Discrete Event Modelling: Experience with the Transaction, Activity, and Event Approaches, Transactions of the Society for Computer Simulation, 2, 1, 27-56. -- Greg Lomow lomow@cpsc.calgary.cdn or ....![ubc-vision,ihnp4]!alberta!calgary!lomow