NetNews Usenet Archive 1992 #19/NN_1992_19.iso/spool/comp/simulati/56

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Volume: 29, Issue: 1, Tue Sep  1 14:58:40 EDT 1992

+----------------+
| TODAY'S TOPICS |
+----------------+


[GENERAL INFORMATION]
  SUMMARY: Automated Air Traffic Control
[NEW QUESTIONS]
  Location of Company Producing QASE
  GLAS Simulator
  Simulated Vision
[PUBLICATIONS]
  Parallel Logic Simulation
[CALL FOR PAPERS/PARTICIPATION]
  Modelling for Computer Performance Evaluation
[DEPARTMENTS]
  Simulation in the Service of Society

* Moderator: Paul Fishwick, Univ. of Florida
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Subject: [GENERAL INFORMATION]


------------------------------


Date: Fri, 28 Aug 92 15:59:03 EDT
From: [e-mail] (Yilmaz Cengeloglu)
To: [e-mail]
Subject: Re:  Automated Air Traffic Controlling and Blackboard System


    Hi :


    This is all responses I have received about ATC. There is
    another file which has references about BBA. If you want
    BBA file, let me know.

    I  am reiviewing this file with mail -f <filename>. I am
    not sure if you can do some thing after you have received.
    file format might be changed.
    If you have any problem with file, let me know. I will send
    you back.

    Thank you all for your help & interest. If you make further study
    on this area please let me know.

                    Yilmaz Cengeloglu
                    Univ. of Central Florida
                    Dept. of Computer Eng.
                    Orlando, FL

                    [e-mail]



 -------- CUT HERE ---------------------------
>From [e-mail] Fri Aug 14 16:13:08 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.edu
Organization: mit
Cc:

I'm planning on doing some work with expert systems / AI in the
ATC area in the future. i'd appeciate any info you collect..

 -bri



>From [e-mail] Fri Aug 14 17:47:58 1992
To: [e-mail]
Subject: Re:  HELP: Automated Air Traffic Controlling and Blackboard System

Hi,
  Can you please send me the list of references that you alluded to in your
post and any other info.
  Thanx
rumi

>From [e-mail] Fri Aug 14 22:55:51 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.edu
Organization: The MITRE Corporation, McLean, VA

In article <[e-mail]> you write:
>I will write simple knowledge bases to solve the conflict and other problems
>that occurs at airspace. I do need some help to complete this project and
>graduate.
>
>    If you know any publication related with
>            - Automated Air Traffic Controlling,
>            - books that I can get expertise to write knowledge bases
>              to solve the problems at airspace.
>            - Blackbard Systems AND Air Traffic Controlling.
>
>      please let me know. I will keep all information that I will receive
>         and I will send anyone request later.
>
>      If you know any existing system, project, company related with
>      Automated Air traffic controlling, please let me know. It will
>      be very helpful for my project.

I work for the MITRE corporation, the Federally Funded R&D Center for the FAA.
We have developed 3 large automated ATC systems over the past 15 years, each
is known as Automated En-Route ATC 1, 2, and 3 (AERA, AERA2, AERA3).  As it
happens, the AERA2 system attempted to develop a knowledge base of simple
1 on 1 conflict resolution actions (the APR project).  I suspect you could get
a copy of one or more relevant MITRE technical reports for free (gov't
sponsored work and all that).
>
The software which constucted the systems would be of little interest (PL/1,
and Pascal) but the APR work was done in Lisp.  You might find something there.

Have you checked with the folks at Embry Riddle University in Daytona Beach?
I think they have substantial knowledge in ATC issues and past work.

Best of luck.

Randy
[e-mail]
 --

| Randy Crawford        [e-mail]        The MITRE Corporation
|                                                 7925 Colshire Dr., MS Z421
| N=1 -> P=NP           703 883-7940              McLean, VA  22102

>From [e-mail] Sat Aug 15 00:34:48 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.shells
Organization: Software Technology Branch - NASA/Johnson Space Center
Cc:

If you're interested, I think I still have a copy of a version of CLIPS
developed by the National Research Council of Canada called BBCLIPS
(Black Board CLIPS). They also developed a version with some fuzzy logic
capabilities.

Gary Riley
NASA/Johnson Space Center



>From [e-mail] Sat Aug 15 11:08:36 1992
To: [e-mail] (Yilmaz Cengeloglu)
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.edu

Not much is known in the area you are studying. (I work for TRW on the
FAA's system engineering support activity.) You might contact MITRE in the
Washington DC area.


 --
Harry Erwin
Internet: [e-mail]


>From FCS$[e-mail] Sat Aug 15 14:49:25 1992
Subject: HELP: Automated Air Traffic Controlling and Blackboard System
Sender: FCS$[e-mail]
To: [e-mail]
X-Organization: Southeastern Louisiana University
X-Vms-To: in%"[e-mail]"
X-Vms-Cc: FCS$1224

When I was at the Jet Propulsion Laboratory several years ago one summer
there was some discussion going on about the air trafic control systems.
Ai was mentioned, but I was not part of the group, so I do not really
know what actually happened.

You might give Dr. Harry Ashkanas a call.  He handles university contacts
during the summers.  He might be able to point you to who to contact.

JPL is owned and operated by CalTech.  Its location is Pasadena, California.
The general telephone number is 818  354-4321.  I think that Dr. Ashkanes's
number is 354-8251.

I would like a copy of your BBA references.

Thanks,

Tom

[e-mail]

X-News: altair.selu.edu comp.ai.shells:163

>From: [e-mail] (Yilmaz Cengeloglu)
>Subject:HELP: Automated Air Traffic Controlling and Blackboard System
>Date: Fri, 14 Aug 1992 18:25:13 GMT
>Message-ID:<[e-mail]>

>
>
>Hi :
>
>I have asked help about Blackboard Architecture couple of months ago.
>I have received some responses. Thanks to everyone who helped me. I have
>the list of several references related with BBA. If any anyone needs please
>let me know.
>
>Currently I am still working on my project for my thesis and I neen some more
>help. I am explaining what I need first. If you are interested what I am doing
>you can continue to read after line.
>
>I will write simple knowledge bases to solve the conflict and other problems that
>occurs at airspace. I do need some help to complete this project and graduate.
>
>    If you know any publication related with
>            - Automated Air Traffic Controlling,
>            - books that I can get expertise to write knowledge bases
>              to solve the problems at airspace.
>            - Blackbard Systems AND Air Traffic Controlling.
>
>      please let me know. I will keep all information that I will receive
>         and I will send anyone request later.
>
>
>      If you know any existing system, project, company related with
>      Automated Air traffic controlling, please let me know. It will
>      be very helpful for my project.
>
>                                           Yilmaz Cengeloglu
>                                           Univ. of Central Florida
>                               Dept. of Computer Eng.
>                               Orlando, FL
>
>                                           [e-mail]
>                                      or
>                               [e-mail]
>
>
>---------------------------------------------------------------------------------
>
>I am preparing prototype Automated Air Traffic Controlling (A-ATC) system to
>prepare and test knowledge bases for each plane in the airspace. I did need a Blackboard
>shell for my project. Only commercial system that I found was GBB that marketed by
>
>Blackboard Technology Group, Inc.;
>401 Main St., Amherst, MA  01002, 413/256-8990,
>fax: [phone].
>
>Their price was too high for me to buy as a graduate Student. I have implemented my
>own Blackboard System on SunOS operating system. ( I am not really sure if I should
>call Blackboard System.) Different knowledge bases in CLIPS working as a different
>process on the background and uses Blackboard when it is necessary to share fact with
>other knowledge sources. Of course, any other process in C, C++, etc can access the
>Blackboard. The type of architecture is easy to distribute more than one computer
>using computers networks. If I would continue the project after I got my M.S.
>I am still testing it.
>
>Also, I did implemented a Radar Simulator Using C/C++, X-Windows and IPC facilities
>on the SunOS operating system.  Radar simulator is being used by Intelligent Simulation
>and Training systems Project at UCF.
>
>A-ATC project is integration of Radar Simulator and Blackboard System.
>
>

>From [e-mail] Sat Aug 15 12:08:53 1992
To: [e-mail]
Subject: air traffic control

Hi Yilmaz,

suggestion:  contact Kevin Benner at [e-mail]
He's been working on it, and is a good guy.
(I don't know anything about air traffic control myself).
Good luck,

Benjamin

>From [e-mail] Sat Aug 15 21:23:34 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai
Organization: Computer Science & Engineering, Univ. of Texas at Arlington
Cc:

I would HIGHLY recommend that you look into the literature on the
Voronoi diagram in computational geometry.  There is a recent
ACM Computing Surveys article.  The Voronoi diagram will indicate
for each point in a set, the region of points that are closer to that
point than to all the others.  This is very useful for proximity
problems such as:  the air traffic problem and which pizza hut
or police station you should call.  The Voronoi diagram does
not address the movement of the points, but it gives a good
prioritization of potential collisions.

I have a masters student who is doing a dynamic voronoi diagram
with points that have "programs" for their movement.  As the
points move, the voronoi diagram will be recomputed (in n log n time).

Bob Weems
Associate Professor

>From [e-mail] Sun Aug 16 15:09:56 1992
To: [e-mail]
Subject: Re:  HELP: Automated Air Traffic Controlling and Blackboard System
Cc: [e-mail]

Hi,

  I researched the subject some time ago and was working on a proposal for
self managing air traffic (SMART system) in which all aircraft would manage
their requirements autonomous and use ATC only as a directory service for
weather info, airport utilization, etc - in turn, aircrafts would 'broadcast'
their position, their local weather, their intentions, etc. The concept of
one central organization (ATC) controlling traffic would be a thing of the
past. Pretty long story and many many details - turns out based on simulations
we did that we could handle about 5x of today's traffic - after talking to
several FAA/RTCA/Mitre/.. people, however, I concluded that the FAA is moving
just to slow and too conservative to make this happen - I was even in contact
with European officials in hope one would be more open to such proposals due
to the distributed character which fits Europe structure much better - but
'no' on that end as well. So, sometime last year we killed the research
project due to 'lack of interest' ... maybe someday (when the time is ripe)
we'll talk about it again.

  There are 'mountains' of literature available on the subject - however, to
come up to speed rather quickly I suggest the following things (pls let me
know if you need more details in aspecific area):

1. RTCA - contracted by the FAA to deal with these issues - their anual
   proceedings give you a good idea and pointers to material (202-682-0266)
   Last issue Dec 91.

2. NTIS (Government Printing office): Safe Skies for Tomorrow: Aviation
   Safety in a competitive Environment (Jul 88)

3. FAA: Aviation Systems - Capital Investment Plan (Dec 90)

4. IEEE: (a) proceedings of the IEEE (Nov 89) - special issue on ATC
   (b) 10th Digital Avionics Systems Conference (Oct 91)
   (c) Transactions on Aerospace and Electronic Systems
   (d) Spectrum magazine - special issue on ATC - Feb 91

5. DOT: Concepts and Description of the Future Air Traffic Management Systems
   for the United States

As I said there's lots more - but this a good start.

Good luck, Jens Horstmann.


>From [e-mail] Sun Aug 16 16:44:36 1992
To: [e-mail]
Subject: Databases for blackboards


[e-mail] (Yilmaz Cengeloglu)
[e-mail]


Yilmaz,

You may consider using an SQL complient database server as
the host for your blackboard system, and extend CLIPS and
other ES/KB shells to use the system. In this manner, their
data is represented as a simple SQL query for data. One
process updating the data and other processes making the
decisions. This allows you complete freedom in choosing
KB shells, providing they can be hacked to support SQL.

We are working on the use of a blackboard to tie facilities
databases together. Our problem is where many proprietary
vendors maintain their own databases which, with any one
vendors access software do not provide us with an acceptable
view of all activity within the buildings. For instance, the
electrical monitoring system data is unavailable to either the
fire alarm system or the lighting and occupancy sensor system.

Our architecture is TCP/IP network, Sun Sparc as a server,
X/Windows for access and display. We chose a true database
server to tie other databases together for a single access
viewpoint.

We chose to go with Ingres, as most of our data points are
contained with in the lighting system, whose database is
Ingress, SCO SVR4. During this process we noted the existance
of Postgres, available from Berkeley via FTP. This system
runs on SUN Sparc and will require Kernal modifications to
support shared memory. It is a true database server model.
It has SQL interface, which should allow your blackboard users
(clients) to access the system.

Our system will utilize expert systems, and neural networks
to monitor the buildings and to assert their own alarms and
actions for our $5/hr guards to take. We will be
using CLIPS and other shells, (Norvig's shell, modified, running
under CMU  CLOS Lisp FTP from CMU.).

We are just getting to the implementation stage, having acquired
Postgress and CMU lisp. We have a copy of pm/mali - a lambda prolog
completely _unlike_ Edingbourgh Prolog. We have an older version
of CLIPS and a tiny ES in Borlands Turbo-prolog awaiting porting
to pm/mali.

Info on Postgres: postgres.berkeley.edu. (Free for educational use.)
Other program data may be obtained from archie, and may already
be available at your site.

I don't recommend wading into pm/mali lambda prolog, as it is poorly
documented within its package.


Bye, the Bye, I spent 18 mo's in the UCF (Then FTU's) math department.
Please send me more info on your results, as they seem to have
the same architectural feel as the facilities project we are
undertaking.

 --Wayne

Wayne Green      NCAR (National Center for Atmospheric Research)
P.O. Box 3000, Boulder Colorado, 80307-3000
[phone]        FAX [phone]   [e-mail]

>From [e-mail] Mon Aug 17 05:59:08 1992
X-Mailer: QuickMail/SMTP interface.
To: Yilmaz Cengeloglu <[e-mail]>
Subject: BBA

Date    17.8.1992
Subject    BBA
From    Thomas Cord
To    Yilmaz Cengeloglu

                      BBA
Hi,

I'm interested in having your list of references related with BBA. Could you
please send it
to me? Thanks!

I'm working on a Project together with some european institutes. The project
aims to develop and assess an approach where knowledge-based and artificial
vision techniques are combined to control and supervise product quality in meat
transformation processes. An artificial vision system will be designed for the
purpose of automatic data collection and intelligent parameters processing;
i.e., in order to collect different product features and to identify and assess
the related quality parameters. A knowledge-based system will make the
evaluation of product quality less subjective and experiental and more
standardised. Two manufacturing processes will be adopted as test cases for the
research work.

For the knowledge-based system we prefer a blackboard architecture. Because of
the high prices we cannot buy a blackboard shell. Like you, we want to use
CLIPS. Because our project is beginning now, we have specified only the global
system architecture. Detailed
examinations of BBA and knowledge representations will begin now. It would be
very helpful
for me, if you could give me more informations about the design of your
knowledge-based
system.

For the managment of the application and user interface we try to use a C++ -
library. Could
yoe give me some hints about the integration of CLIPS and C++? Is there a
possibility
of compiling CLIPS in an C++ environment?

Thank you very much for your help!
Thomas Cord

Here is my address:

Thomas Cord
Forschungszentrum Informatik (FZI)
Haid-und-Neu-Stra'e 10-14
D-7500 Karlsruhe 1
Germany
Phone:  [phone]
Fax:     [phone]
e-mail: [e-mail]



>From [e-mail] Sun Aug 16 17:22:30 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.shells
Organization: Infologics AB, Sollentuna, Sweden
Cc: [e-mail]
X-Charset: ASCII
X-Char-Esc: 29

In article <[e-mail]> you write:
>
>Hi :
>
>I have asked help about Blackboard Architecture couple of months ago.
>I have received some responses. Thanks to everyone who helped me. I have
>the list of several references related with BBA. If any anyone needs please
>let me know.

I too have done some surveying of the literature recently, but I
cannot remember having seen anything that is both BBA and Air Traffic
Controlling.

By any chance, have you got any references on the use of BBA in
telecommunications applications, such as monitoring of networks?

________________________________________________________________________
Rabbe Fogelholm, Infologics AB     [e-mail]    fax: [phone]

>From [e-mail] Sun Aug 16 18:41:17 1992
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
To: [e-mail] (Yilmaz Cengeloglu)
X-Mailer: ELM [version 2.3 PL11]

Let me know how things work out.  Bob

>From [e-mail] Mon Aug 17 14:41:13 1992
To: [e-mail] (Yilmaz Cengeloglu)
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai

try mailing [e-mail].  He is currently involved
in writing an ATC type blackboard system.

Nigel.

>From [e-mail] Mon Aug 17 15:14:36 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling
Newsgroups: rec.aviation
Organization: Schlumberger Laboratory for Computer Science
Cc:


There was a paper on the subject in the 1982 AAAI conference by some people at
RAND.  It was primarily a distributed AI paper, but used ATC as a domain.

I think also the guy behind the TRACON game did some AI for ATC research some
years ago---Robert Wesson.

Eric
 --
Eric Schoen
Schlumberger Laboratory for Computer Science
Internet: [e-mail]   In the air: N201DR
USMail: P.O. Box 200015, Austin, TX, 78720-0015

>From [e-mail] Mon Aug 17 17:01:29 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai
Organization: Institut Imag, Grenoble, France
Cc:

In article <[e-mail]> you write:
>
>    If you know any publication related with
>            - Automated Air Traffic Controlling,
>            - books that I can get expertise to write knowledge bases
>              to solve the problems at airspace.
>            - Blackbard Systems AND Air Traffic Controlling.
>[...]
>      If you know any existing system, project, company related with
>      Automated Air traffic controlling, please let me know. It will
>      be very helpful for my project.

There is an AI group at Eurocontrol, the european authority for air traffic
control. I do not have the adress at hand right now, but if nobody else gives
you a lead, just post me a mail reminding me to send it to you. There is also
a conference serie called ``HMI and AI in Aeronautics and Space''. For more
information, you can try and ask Guy Boy ([e-mail]): if I'm right,
he was the Program Chairman, at least in 88 and probably also in 89. About
that also, I could find more, if you need it. I just wanted to make sure
you were aware of the existence of Eurocontrol's AI group.
>
>Blackboard Technology Group, Inc.;
>401 Main St., Amherst, MA  01002, 413/256-8990,
>fax: [phone].
>
>Their price was too high for me to buy as a graduate Student. I have implemented my
>own Blackboard System on SunOS operating system. ( I am not really sure if I should

I think there is a version of GBB that is available free or almost free for research
purpose by FTP: try dime.cs.umass.edu (but the information may be obsolete).

Hope it helps. Do not hesitate to ask for more precision, if nobody provides them.

christian


 --
Ch. de Sainte Marie - 3A.S.I. ltd - 4, rue Chanaron - 38000 Grenoble - FRANCE
                      LIFIA - 46, av. Felix Viallet - 38031 Grenoble - FRANCE
[e-mail]
Disclaimer : I am the company              ``C'est ephemere et c'est moi...''

>From calsci!sjain Mon Aug 17 21:29:13 1992
Subject: Copy of Blackboard references
To: [e-mail]

Dear Yilmaz,
       I wonder if you could send me a copy of your blackboard references.
                Thanks/
                                                Sandeep Jain

>From [e-mail] Tue Aug 18 03:18:46 1992
Subject: ATC
To: [e-mail]
X-Vmsmail-To: SMTP%"[e-mail]"

Hi,

the follow info may help you.
1)    Proc IEEE Nov 1989 is a special issue on ATC

2) the Australian Artificial Intelligence institute has written
a kbs system for automated flow control in PRS.  This is to be
installed at Mascot Sydney Australia.  Contact Andrew Lucas
             [e-mail]

I'm interested in other responses you may have had to your request

Hope this helps
Simon Goss
DSTO Aircraft Systems Division
AUSTRALIA

>From [e-mail] Tue Aug 18 11:40:42 1992
Organization: Universitaet des Saarlandes
              D-W-6600 Saarbruecken, Germany
To: [e-mail] (Yilmaz Cengeloglu)
Subject: HELP: Automated Air Traffic Controlling and Blackboard System

hello yilmaz,
can you send me please the list of references related with BBA.
by the way, you can have a look at
"Distributed Intelligence for a Air Fleet Control"
R. Steeb, S. Cammarata, F. Hayes-Roth, P. Thorndyke and R. Wesson
in 'Readings in Distributed Artificial Intelligence' edited by Alan H.
Bond and Les Gasser, Morgan Kaufmann, 1988

alassane
 -------------------------------------------------------------
|NET: [e-mail]                    |
|-----------------------------------------------------------|
|POST: Alassane NDIAYE          |                        |
|      FB 14 - Informatik IV       | PHONE: [phone]|
|      Universitaet des Saarlandes |                        |
|      Im Stadtwald 15           |------------------------|
|      D-6600 Saarbruecken 11       | FAX:   [phone]|
|      Federal Republic of Germany |                |
 -------------------------------------------------------------

>From [e-mail] Wed Aug 19 05:34:07 1992
To: [e-mail] (Yilmaz Cengeloglu)
Cc: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System
Organization: University Zurich, Department of Computer Science

In article <[e-mail]>, you wrote:
>
>
>
> Hi :
>
> I have asked help about Blackboard Architecture couple of months ago.
> I have received some responses. Thanks to everyone who helped me. I have
> the list of several references related with BBA. If any anyone needs please
> let me know.
>
> [remainder deleted]

I recently got involved in a project that uses BBA technology as basis
for the systems architecture. As I haven+t a background in BBA, I would
appreciate it if you could email me your list of references about BBAs.

Thanks in advance.

Rene Sennhauser

>From [e-mail] Tue Aug 18 15:27:45 1992
To: [e-mail] (Yilmaz Cengeloglu)
Subject: blackboards


note that an earlier version of gbb was available free at one point from
the author's university... you might use archie to find if it is
archived somewhere. As for traffic control, I can't help you.


>From [e-mail] Tue Aug 18 21:24:52 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling
Newsgroups: rec.aviation
Organization: Oracle Corporation, Belmont, CA

I know of no books on automated ATC although you might look
to see if NASA or the Air Force has technical reports on ATC or
target tracking, e.g., systems like AWACS (Airborne
Warning And Control System).

Have you seen the FAR (Federal Air Regulations) / AIM (Airman's
Information Manual) document?  It describes the regulations for
instrument flight (for which ATC was intended to serve) as well
as some of the practical rules of such flight.  The document is
a standard reference for pilots and is available at pilot shops
or campus bookstores where they teach pilot ground school.
It has interesting facts such as the procedure a pilot should
follow if his or her radio goes out while flying in instrument
conditions.

You can also take a tour of the local ATC center in your area
to see how things are done from a practical standpoint.  Look
in the phone book under FAA for the Air Route Traffic Control
Center, Terminal Radar Control Facility, or Flight Service
Station.

I think you will find that ATC as well as piloting are not
problems that can be easily automated.  Pilots and controllers
enjoy a great deal of discretion in their actions.  This is necessary
due to the significance and unpredictability of the media in which
airplanes fly, the weather, and to the tenuous link between ATC
and aircraft, a simplex voice radio channel.

As far as I can tell, automation in the current ATC system is
limited to controller's sensing systems (e.g., radar mosaic imaging),
and distributed database systems (e.g., the flight plan database, and
weather reporting systems).

Good luck,

 --Dan

>From daemon Wed Aug 19 09:02:29 1992
To: [e-mail]
Subject: GBB...


By the way,  do you know that a public domain version of GBB is available
by anonymous FTP at dime.cs.umass.edu (directory /gbb)

What you won't get (compared to the commercial GBB) is the graphical user
interface. I vaguely remember that GBB has a graphical module for Explorer
however.

Best regards,

Fano

PS: I didn't notice your first request about GBB.


>From wisdom!tronsbox.uucp![e-mail] Wed Aug 19 21:10:55 1992
Apparently-From: tronsbox!tronsbox!moskowit
To: [e-mail]
Subject: Air Traffic Control


See the Proceedings of the National Aerospace Electronics Conference
(NAECON), held yearly at Wright-Patterson Air Force Base out in
Dayton, Ohio.  It's published by the IEEE.  This year ('92) had at
least one paper on the subject and I recall others in previous years.


Len Moskowitz
Senior Staff Engineer
Allied-Signal Aerospace Company
Bendix Guidance and Control
Teterboro, NJ 07608

([e-mail]
    or
 [e-mail])


>From [e-mail] Thu Aug 20 11:21:44 1992
Subject: BBs for Traffic control
To: [e-mail]

  BBs for Traffic control
  Would you be interested in references to a paper about a BB inspired system
  for URBAN traffic control ?

  I would think that some of the problems can be described the same way
  (congestion, accidents, saturation flow, .....).

  Just give me a mail and I will write down a selected list of references.

  C
  ----------------------------------------------------------------------------
  Christen Krogh [[e-mail]], Center for Industrial Research, Oslo, NORWAY.
  ----------------------------------------------------------------------------


>From [e-mail] Thu Aug 20 20:21:18 1992
To: [e-mail]
Subject: Re:  Query: Automated Air Traffic Control

In comp.ai.nlang-know-rep you write:

>From: [e-mail] (Yilmaz Cengeloglu)
>Subject: Query: Automated Air Traffic Control and Blackboard Systems
>Date: Fri, 14 Aug 1992 18:28:31 GMT
>
>Hi :
>
>I have asked help about Blackboard Architecture couple of months ago.
>I have received some responses. Thanks to everyone who helped me. I have
>the list of several references related with BBA. If any anyone needs please
>let me know.
>
>Currently I am still working on my project for my thesis and I neen some more
>help. I am explaining what I need first. If you are interested what I am doing
>you can continue to read after this line.
>
>I will write simple knowledge bases to solve the conflict and other
>problems that occurs at airspace. I do need some help to complete this
>project and graduate.
>
>    If you know any publication related with
>        - Automated Air Traffic Controlling,
>        - books that I can get expertise to write knowledge bases
>          to solve the problems at airspace.
>        - Blackbard Systems AND Air Traffic Controlling.
>
>      please let me know. I will keep all information that I will receive
>         and I will send anyone request later.
>
>      If you know any existing system, project, company related with
>      Automated Air traffic controlling, please let me know. It will
>      be very helpful for my project.
>
>                                       Yilmaz Cengeloglu
>                                       Univ. of Central Florida
>                           Dept. of Computer Eng.
>                           Orlando, FL
>                                       [e-mail]
>                              or
>                           [e-mail]
>
>- ------------------------------------------------------------------------------
>
>I am preparing prototype Automated Air Traffic Controlling (A-ATC)
>system to prepare and test knowledge bases for each plane in the
>airspace. I did need a Blackboard shell for my project. Only
>commercial system that I found was GBB that marketed by
>
>Blackboard Technology Group, Inc.;
>401 Main St., Amherst, MA  01002, 413/256-8990,
>fax: [phone].
>
>Their price was too high for me to buy as a graduate Student. I have
>implemented my own Blackboard System on SunOS operating system. ( I am
>not really sure if I should call Blackboard System.) Different
>knowledge bases in CLIPS working as a different process on the
>background and uses Blackboard when it is necessary to share fact with
>other knowledge sources. Of course, any other process in C, C++, etc
>can access the Blackboard. The type of architecture is easy to
>distribute more than one computer using computers networks. If I would
>continue the project after I got my M.S.  I am still testing it.
>
>Also, I did implemented a Radar Simulator Using C/C++, X-Windows and
>IPC facilities on the SunOS operating system.  Radar simulator is
>being used by Intelligent Simulation and Training systems Project at
>UCF.
>
>A-ATC project is integration of Radar Simulator and Blackboard System.


If you haven't already seen it, you may be interested in Robert
Wesson's 1977 doctoral dissertation "Problem-Solving with Simulation
in the World of an Air Traffic Controller" (University of Texas at
Austin).  You might also want to check out the current incarnation
of that work, a computer game (Mac or PC) called "TRACON II".

Hope this helps!


Karen Ward ([e-mail])
Oregon Graduate Institute


>From [e-mail] Fri Aug 21 04:30:24 1992
Subject: re BBAs
To: [e-mail]

  re BBAs
  Dear Yilmaz Cengeloglu,

  For plain BBA references it would be best to consult a standard AI textbook
  (eg. Rich). Perhaps a search through your librarians database would give you
  the general references you need.

  When it comes to BBAs (or in our case BB*inspired*As) for control of real
  life traffic (be it trains, plains or automobiles) I do not think that there
  are much literature available. Hopefully you'll find something useful among
  our papers.

  Keep me informed about how you are getting on!

  - Christen

  ---------------references-------------------

  1.    Krogh C., Irgens M, Traetteberg H; "A novel architecture for traffic
  control"; Vehicle Navigation and Information Systems (IEEE), Oslo, September
  2-4, 1992.

  2.    Ambrosino G., Bielli M., Boero M., Kirschfink H., Krogh C., Fleischman S.;
  "IUTCS: a knowledge-based blackboard architecture for advanced urban traffic
  management and control"; Proceedings from "OECD Workshop on Knowledge-based
  Expert Systems in Transportation"; Montreal, Canada; June 15 - 17, 1992.

  3.    Ambrosino G., Bielli M., Boero M., Fleishcmann S. Hock R., Irgens M.: A
  Blackboard Model for Traffic Control Operations. Drive Conference, Bruxelles
  4th-6th February 1991.s

  4.    M.Irgens, M. Bielli, M. Boero, S. Fleischman and R. Hock: Towards
  Intelligent Urban Traffic Control. Proceeding, OECD Workshop on Knowledge
  Based Expert Systems in Transportation, 1990.

  5.    Irgens, M. and Krogh, C.: The IUTCS Blackboard. Users Manual. SI Report
  No. 89 01 62 - 3. November 1990. ISBN 82-411-0258-5. November 1990.

  ----------------------------------------------------------------------------
  Christen Krogh [[e-mail]], Center for Industrial Research, Oslo, NORWAY.
  ----------------------------------------------------------------------------


>From [e-mail] Mon Aug 24 07:56:19 1992
To: [e-mail] (Yilmaz Cengeloglu)
Subject: HELP: Automated Air Traffic Controlling and Blackboard System


Being professionnaly working in a field very close to your thesis
subject, I would advise you to contact the MITRE corporation. The
AERA-3 ATC system design might very much interest you and they are the
most competent people for information on this subject in the USA.

A team has developped in France a very large knowledge based system
(ERATO) for detecting and solving conflicts, built upon a cognitive
model of the Air Traffic Controller. It is a very large project,
including many people. The head of the project is Marcel Leroux
([e-mail]).

Hope this helps.

 ---------------------------------------------------------------------
Jean-Marc Alliot
Centre d'Etudes de la Navigation Aerienne (CENA)
Direction Generale de l'Aviation Civile (DGAC)
[e-mail]
 ---------------------------------------------------------------------

>From cs.ucf.edu!darwin.sura.net!wupost!uunet!sun-barr!ames!agate!rsoft!mindlink!a3744 Wed Aug 26 11:36:56 EDT 1992
Article: 10725 of comp.ai
Path: cs.ucf.edu!darwin.sura.net!wupost!uunet!sun-barr!ames!agate!rsoft!mindlink!a3744
Newsgroups: comp.ai
Subject: Re: Automated Air Traffic Controlling and Blackboard System
Organization: MIND LINK! - British Columbia, Canada
Distribution: world

A Project called CAATS "Canadian Automated Air Traffic System is being
developed by Hughes Aircraft Canada Division here in Vancouver British
Columbia,....16 CSCIs are being developed within a Rational Enviroment which
will result in the most advanced ATC system in the world.

I would be pleased to address amy technical questions you may have.

Steve Sawyer
Mindlink, Vancouver, BC
Canada
/x


>From [e-mail] Fri Aug 28 02:44:42 1992
X-Mailer: QuickMail/SMTP interface.
To: Yilmaz Cengeloglu <[e-mail]>
Subject: BBA

Date    28.8.1992
Subject    BBA
From    Thomas Cord
To    Yilmaz Cengeloglu

                      BBA
Hi,

Thank you very much for your help!

Thomas Cord




>From [e-mail] Wed Aug 26 16:49:23 1992
To: [e-mail]
Subject: Re: HELP: Automated Air Traffic Controlling and Blackboard System

If you send me your mail address, I'll send you a copy of BBCLIPS.

Gary

>From [e-mail] Thu Aug 27 13:57:17 1992
Subject: Blackboard references
To: [e-mail]
X-Mailer: ELM [version 2.3 PL6]

Please send me a copy of the blackboard references that you
have collected.

Thanks,

David Schwartz

[e-mail]

>From [e-mail] Wed Aug 26 09:44:11 1992
To: [e-mail]
Subject: Re:  Automated Air Traffic Controlling and Blackboard System

Perhaps you can send the summary of responses to your original question
(to comp.simulation). Thanks

 -pf


>From [e-mail] Wed Aug 26 14:58:31 1992
To: [e-mail]
Subject: Re: Automated Air Traffic Controlling and Blackboard System

  I would be interested in the information that you have collected.
  Thanks.  Bob Avanzato, Penn State University, [e-mail]

>From [e-mail] Wed Aug 26 16:43:48 1992
To: [e-mail]
Subject: Re: Automated Air Traffic Controlling and Blackboard System
Newsgroups: comp.ai.edu
Organization: mit
Cc:

please send me all the responses you got to the ATC question

 -bri



>From [e-mail] Thu Aug 27 12:53:34 1992
To: [e-mail]
Subject: air traffic control

In the speech understanding domain -- specifically use of dialog, proagmatics
and semantics to dynamically change the search space for words in the speech
signal --- there was a system built in france for training air traffic
controllers.  Although this architecture is similar to a blackboard
architecture, is differs in that knowledge from one components actually
modifies what another component can do.

Anyhow, the project was beta-tested.  Some references can be found in ICASSP
91 (or 90?) by Matrouf, Neel etc.  They also wrote a few other papers.

You can also contract Francois Neel at LIMSI -CNRI in Orsay France (outside
Paris).  If you send me more information I can also have my secretary xerox
the articles I have from them - if they are the sort of thing you're looking
for.

Sheryl Young
School of Computer Science
Carnegie Mellon University
Schenley Park
Pittsburgh, PA 15213
[e-mail]

>From [e-mail] Thu Aug 27 21:19:04 1992
Subject: Automated Air Traffic Controlling and Blackboard System
To: [e-mail]
X-Mailer: ELM [version 2.3 PL11]

Hi,

I read with interest an article posted by you in comp.ai on the above subject
matter.  I wonder if you could email me a copy of the responses.  Thanks much.


Regards,
Hong-Gian Chew

>From @pucc.PRINCETON.EDU:[e-mail] Fri Aug 28 11:54:37 1992
To: [e-mail]



Merhaba Yilmaz,


      News'ini gordum. Ulasan bilgileri bana da mail eder misin ?
Calismalarinda basarilar.

                                 Izzet Sirin

                                 [e-mail]

                                 Bilkent Universitesi
                                 Bilgisayar ve Enformatik Muh.
                                 06533 Ankara TURKIYE







------------------------------


Subject: [NEW QUESTIONS]


------------------------------


Date: Wed, 26 Aug 92 16:35:31 PDT
From: [e-mail] (Marke Clinger)
To: [e-mail]
Subject: QASE


Can someone point me in the direction of the company that produces
QASE? I need some technical information on this simulation product.

Thanks,

Marke

__________________________________________________________________________
Marke Clinger                    Ultra Network Technologies
Western Region Systems Engineer            1942 Broadway Suite 213
[e-mail]                    Boulder, CO 80302
                        TEL: [phone]
                        FAX: [phone]




------------------------------

From: [e-mail] (Geoffrey Letsoalo)
Subject: GLAS Simulator.
To: [e-mail]
Date: Fri, 28 Aug 92 12:19:36 SAT
Cc: [e-mail] (Geoffrey Letsoalo)
X-Mailer: ELM [version 2.3 PL11]

I wonder if anyone could help me locate a simulation framework
called General LAN Analysis System (GLAS). GLAS uses the
analytic and simulation techniques to obtain the LAN performance
predictions.

It appears (from the SIMULATION journal of November 1990 pages
283-298) that GLAS has been developed at the University of Kansas,
centre for research.

Hoping my request to receive your favourable consideration.
 --
Geoffrey M. Letsoalo               | The problem with the New South Africa
Data Network Architectures Lab     | is that it's full of old South Africans.
Dept. of Computer Science          |
University of Cape Town            | E-Mail : [e-mail]
Private Bag Rondebosch             | Fax    : [phone]
7700 South Africa                  | Voice  : +27.21.650.2670




------------------------------

Newsgroups: comp.simulation
Path: cc.curtin.edu.au!syawanar
From: [e-mail]
Subject: Simple Vision Simulation
Sender: [e-mail] (News Manager)
Organization: Curtin University of Technology
Date: Tue, 1 Sep 1992 15:39:20 GMT
Apparently-To: [e-mail]


In my fourth (and final) year in engineering, I have been asked to do
the impossible..

Supoose A robot was have only four photocells for a vision system..
How would it be possible for it to see effectively? This is how the
cells divide the view..



     +----------+-----------+
     |          |           |
     | Cell 1   |  Cell 2   |
     |          |           |
     +----------+-----------+
     |          |           |
     | Cell 3   |  Cell 4   |
     |          |           |
     +----------+-----------+

The vision cone is 120 degrees from the left edge to the right edge
and 120 degrees from the top edge to the bottom edge. I have found that by
sweeping through a 120 degree 'fan' in 1 or 2 degree steps (whilst taking
readings at each step) one can construct a *crude* view of what is ahead.

What I need to do is write a program that will simulate the robot moving
thru a 3D world. Once a certain object looms ahead (in proper 3D, with
shading..) then the user hits a key and the robot is required to give it's
own interpretation of what it 'sees' by means of the 'simulated' sensors.
IE, the screen is split into four and each quarter of the screen is 'de-
focused until only the average intensity of the entire quarter is relevant.
This is repeated for each step 2 degrees at a time..
A curve can be plotted from the values obtained at each of the sensors
and patterns might be recognized.. etc..

Any ideas along these lines or anything totally different are most welcome.

+---------------------------------------------------------------+
|Naveen Yawanarajah \ Internet :    [e-mail]   |
|                    \ Fidonet :    3:690/613                   |
| The BEAsT           \ POST   :    4 Woonan Pl., KARAWARA 6152 |
|       goes on!!      \       :    PERTH, WESTERN AUSTRALIA... |
+---------------------------------------------------------------+



------------------------------


Subject: [PUBLICATIONS]


------------------------------


Date: Mon, 31 Aug 92 10:49:18 PDT
From: mtvnec![e-mail] (Larry Soule)
To: [e-mail]
Subject: Technical Report available: Parallel digital logic simulation


A technical report of my dissertation is now available.

Title:      Parallel Logic Simulation: An Evaluation of
    Centralized-Time and Distributed-Time Algorithms

Author:   Lawrence Peter Soule' ([e-mail])

The report can be ordered through the CSL librarian, Naomi Schulman.
She can be reached at 415-723-1430, [e-mail], and at
Naomi Shulman
Computer Systems Lab
ERL 444A
Stanford University
Stanford, CA 94301




------------------------------


Subject: [CALL FOR PAPERS/PARTICIPATION]


------------------------------


To: [e-mail]
Path: dcs.ed.ac.uk!rjp
From: Rob Pooley <[e-mail]>
Newsgroups: comp.simulation
Subject: Fianl programme for Tools and Techniques Conference
Date: 1 Sep 92 15:01:14 GMT
Sender: [e-mail]
Distribution: world
Organization: Department of Computer Science, University of Edinburgh


                            CALL FOR PARTICIPATION

            6TH INTERNATIONAL CONFERENCE ON MODELLING TECHNIQUES
                AND TOOLS FOR COMPUTER PERFORMANCE EVALUATION

                           September 16-18th, 1992
                             Scandic Crown Hotel
                           Edinburgh, Scotland, UK.


The sixth International Conference on Modelling Techniques and Tools
for Computer Performance Evaluation will be held in Edinburgh, UK.
This is the major European forum for the presentation of research and
applications of performance analysis tools and techniques.

The conference will be held in the Scandic Crown Hotel, a modern luxury
hotel in the middle of Edinburgh's historic Old Town, on the Royal Mile.


The provisional programme is given below:

WEDNESDAY 16th SEPTEMBER


9:20 - 9:30     Opening Remarks

9:30 - 10:30    Arnold Allen - invited paper
                Session Chairman: R. Pooley

10:30 - 11:00   Coffee Break

11:00 - 12:00   PETRI NETS (Chairman: G. Balbo)
                C. Lindemann
                  DSPNexpress: A Software Package for Efficiently Solving
                  Deterministic and Stochastic Petri Nets
                J.A. Rolia and K.C. Sevcik
                  Fast Performance Estimates for a Class of Generalized
                  Stochastic Petri Nets

12:00 - 12:30   Overview of tools to be demonstrated (Chairman: M. Calzarossa)

12:30 - 2:30    Lunch and Tool Demonstrations

2:30 - 3:30     MEASUREMENTS  (Chairman: D. Thomas)
                J.K. Flanagan, K. Grimsrud et al
                  BACH: BYU Address Collection Hardware
                N.J. Gunther
                  On the Application of Barycentric Coordinates to the Prompt
                  and Visually Efficient Display of Multiprocessor Performance
                  Data

3:30 - 4:00     Tea Break

4:00 - 5:30     WORKLOADS  (Chairman: G. Serazzi)
                B.M. Carlson et al
                  Speedup Properties of Phases in the Execution Profile of
                  Distributed Parallel Programs
                K.J. McDonell
                  Benchmark Frameworks and Tools for Modelling the Workload
                  Profile
                M.K. Acharya et al.
                  Real-time Hierarchical Traffic Characterization of a Campus
                  Area Network

THURSDAY 17th SEPTEMBER

9:00 - 10:30    ESPRIT III projects  - invited papers
                Chairman: P. Hughes
                Trevor Chambers - ESPRIT project 6942
                  PEPS: Performance Evaluation of Parallel Systems
                Horst Lindmeier - ESPRIT project 6271
                  Benchmarking for Embedded Control and Real-time Applications
                Kam-Fai Wong - ESPRIT project 7091
                  Pythagoras: Performance Quality Assessment of Advanced
                  Database Systems

10:30 - 11:00   Coffee Break

11:00 - 12:30   METHODS I  (Chairman: R. Puigjaner)
                E.W. Brehm, R.T. Goettge and F. McCaleb
                  START/ES - An Expert System Tool for System Performance
                  and Reliability Analysis
                A. Valderruten et al.
                  Deriving Queueing Networks Performance Models from Annotated
                  LOTOS Specifications
                J. Hillston
                  A Tool to Enhance Model Exploitation

12:30 - 2:00    Lunch and Tool Demonstrations

2:00 - 4:00     PARALLEL AND DISTRIBUTED SYSTEMS  (Chairman: R. Candlin)
                F. Hartleb and V. Mertsiotakis
                  Bounds for the Mean Runtime of Parallel Programs
                G. Lyon, R. Snelick and R. Kacker
                  Time-Perturbation Tuning of MIMD Programs
                A. Birman, D. Ferguson and Y. Kogan
                  Asymptotic Solutions for a Model of Large Multiprocessing
                  Systems with Multiple Workloads
                R. Kroeger, M. Gergeleit and F. Lange
                  JEWEL: Experiences with a Distributed Measurement System

4:00 - 5:15     Tea Break and Poster Session
                (Poster Session Organiser: J. Hillston)


FRIDAY 18th SEPTEMBER

9:00 - 10:00    Raj Jain - invited paper
                Chairman: R. Marie

10:00 - 11:00   METHODS II  (Chairman: G. Haring)
                A.L. Opdahl
                  Sensitivity Analysis of Combined Software and Hardware
                  Performance Models: Open Queueing Networks
                N.M. Patel
                  Structuring Analytical Performance Models using Mathematica

11:00 - 11:30   Coffee Break

11:30 - 12:30   METHODS III  (Chairman: P. Harrison)
                R. Chakka and I. Mitrani
                  A Numerical Solution Method for Multiprocessor Systems
                  with General Breakdowns and Repairs
                P. Buchholz
                  Hierarchical Markovian Models - Symmetries and Reduction

12:30 - 2:30    Lunch and Tool Demonstrations

2:30 - 3:30     CASE STUDIES  (Chairman: A. Wight)
                S. Salza and R. Tomasso
                  A Modelling Tool for the Performance Analysis of Relational
                  Database Applications
                M. Malhotra and K.S. Trivedi
                  Reliability of Redundant Arrays of Inexpensive Disks (RAID)

3:30 - 4:00     Tea Break

4:00 - 4:15     Closing Remarks


POSTERS AND TOOL DEMONSTRATIONS

A.E. Krzesinski and N.J. Townsend
        /DASD: A Tool to Model the Performance of IBM DASD Systems

X. Zhang, N. Nalluri and X. Qin
        MIN-Graph: A Tool for Monitoring and Visualising MIN-based
        Multiprocessor Performance

B.R. Haverkort, A.P.A. van Moorsel and A. Dijkstra
        MGMtool: A Performance Modelling Tool Based on Matrix Geometric
        Techniques

A. Hutchison and P.S. Kritzinger
        XWAN: A Tool to Model Adaptive Routing in a Wide Area Network

A.E. Kostin
        Microsim: E-Net Tool for Modelling Concurrent and Distributed Data
        Processing Systems

H. Heiss and A. Payer
        PASTE: A Tool for Evaluation of Processor Allocation Strategies

G. Fleischmann and M. Gente
        Modelling and Evaluation of Parallel Programs using GIANT

G. Fairhurst and A.Z.M. Salleh
        Modelling the Performance of the G.764 Packetised Voice Protocol

R.L. Klevans and W.J. Stewart
        XMARCA: An X-Windows Interface for Queueing Network Modelling

G. Chiola, R. Gaeta and M. Ribaudo
        Designing an Efficient Tool for Stochastic Well-Formed Coloured Petri
        Nets

A.J. Field and R.L. While
        A General Framework for Discrete-Event Simulation Using Functional
        Languages


TUTORIALS

Before the conference, on Tuesday 15th September there will be a programme
of tutorials on aspects of performance modelling.  There will be two long
tutorials in the morning and two sets of two short tutorials in the afternoon.
Delegates may register for either a full day or a half day programme.  Please
indicate choice of tutorial(s) on the registration form.

9:00 - 12:00    A       Nico M. van Dijk,
                        University of Amsterdam, The Netherlands

                        The Product Form Tool

                B       Kishor S. Trivedi
                        Duke University, USA

                        Techniques and Tools for Reliability Modelling

12:00 - 1:30    LUNCH

1:30 - 3:00     C       Ian F. Akyildiz
                        Georgia Institute of Technology, USA

                        Computational Techniques

                D       Edmundo de Sousa e Silva
                        University of Rio de Janeiro, Brazil

                        Numerical Approaches

3:00 - 3:30     COFFEE

3:30 - 5:00     E       Gabriele Kotsis
                        University of Vienna, Austria

                        Visualization of Performance Information

                F       Boudewijn R. Haverkort
                        University of Twente, The Netherlands

                        Performability Modelling Tools


Abstracts for each tutorial are given below:

A  THE PRODUCT FORM TOOL - Nico M. van Dijk

Queueing network modelling has become a popular tool in telecommunication,
computer performance evaluation and flexible manufacturing.  The tutorial aims
to highlight an approach that can be used as an engineering tool to evaluate
stochastic service or computer networks.  To this end, it will cover the
following two topics:

                1) Product forms and partial balance
                2) A simple bounding methodology.

Part 1 will discuss the physical notion of station balance as a key-property
to deduce closed product form expressions for queueing networks with blocking.
In concrete situations this notion will enable one to directly deduce whether
or not a system will have a product form solution, and if not, why not.

In part 2 these insights will be used further to also obtain simple
performance bounds for non-product form queueing networks, most notably
networks with blocking.  The steps involved will be outlined and illustrated
for some typical non-product form examples such as:

        - an overflow model
        - a system with breakdowns
        - finite tandem or assembly lines


B  TECHNIQUES AND TOOLS FOR FOR RELIABILITY MODELLING - Kishor S. Trivedi

Various Markov reward models are described and investigated as a tool to
evaluate reliability and availability models for computer networks, for
example fault-tolerant systems.  Both transient and steady-state measures are
considered.  Techniques covered are:

        - differential equations
        - numerical solution procedures
        - uniformization techniques and truncations
        - simulation procedures and enhancements

Particularly, a hierarchical modelling tool is presented, called SHARPE
(Symbolic Hierarchical Automated Reliability and Performance Evaluation), that
combines the different techniques and models.  This tool provides a
specification language and solution methods for a large number of models such
as:
        - series-parallel reliability block diagrams
        - reliability graphs and fault trees
        - cyclic and acyclic Markov chains
        - Generalized Stochastic Petri Nets
        - PMS (Processor-Memory-Switch) Models



C  COMPUTATIONAL TECHNIQUES FOR COMPUTER NETWORKS - Ian F. Akyildiz

Much of the success of queueing network modelling for computer networks can be
attributed to:

        - the existence of Jackson's closed product form expression and many
          extensions thereof, and
        - efficient computational techniques to actually compute these forms or
          related performance measures such as the throughput, sojourn time or
          loss probability.

This tutorial will survey a number of these computational techniques
ranging from the classical convolution algorithm to various exact and
approximative versions of the MVA (mean value analysis) method like LBANC and
LBANCBLO.  In doing so, special attention is given to different blocking
protocols when finite capacities are involved.  Finally some recent results
are presented to transform networks with blocking into networks without
blocking.


D  NUMERICAL APPROACHES TO PERFORMABILITY - Edmundo de Souza e Silva

The performance of computer networks under different loads and circumstances
is a relevant indication of its being well-designed and operable.  Computer
systems reliability and availability deals with the representation of changes
in structure of the system due to faults or breakdowns.  As analytic tools are
often not feasible to capture such aspects while simulation techniques may be
unreliable, numerical possibilities are still searched for.

An overview is provided of past work on performability evaluation by means of
Markov chains and how relevant performance measures can be computed
efficiently by numerical approaches.  Particularly two important topics are
highlighted:

        - the uniformization or randomization technique to transform
          continuous-time models into discrete-time models
        - the state space explosion by which actual computation becomes
          prohibitively expensive.  Several techniques to deal with this
          problem are discussed.


E  VISUALIZATION OF PERFORMABILITY INFORMATION - Gabriele Kotsis

The art of visualizing the performance of computer systems has gained
increasing interest in the past few years.  The pictorial representation of
performance data will help the system analyst to obtain a better understanding
of what is going on in the system, how it works and why it works (or why not).
Visualized information makes use of the eye-brain system, with its great
pattern recognition capability, in a way that is impossible with purely
numeric data.

This tutorial aims to report on the state of the art in performance
visualization from the analyst's point of view.  The usefulness of
visualization techniques and tools supporting performance analysis will be
investigated.  In particular, the tutorial will contain three modules:

   The State of the Art in Performance Visualization
      This presentation will include: visualization primitives and techniques,
      static versus dynamic displays, display of univariate and multivariate
      data, categorization and comparison of existing visualization tools.

   Representing Performance Characteristics of Conventional Computer Systems
      The following topics will be discussed: visualization of hardware and
      software performance information, meaningful metaphors and easy
      recognizable presentation techniques.

   Visualizing the Performance of Parallel and Distributed Systems
      The particular problems arising in visualizing the behaviour of parallel
      systems (representations for massive amounts of data, representation of
      concurrency, visualization of hardware-software mapping) will be
      demonstrated along with possible solution techniques.


F  PERFORMABILITY MODELLING TOOLS - Boudewijn R. Haverkort

Over the last few years Markov reward models (MRMs) have been used extensively
for the analysis of the performability of computer and communication systems.
Using MRMs for this purpose brings along two basic problems: model generation
and model solution.  Model solution has been the subject of study in a large
number of papers.  Far less attention has been paid to the model generation
problem.

In this tutorial the mathematical background of MRMs for performability
modelling is briefly addressed.  The emphasis is then on high-level
specification techniques for performability models and various generation
techniques that can be used to automatically generate MRMs from these
specifications.  Aspects addressed are modelling requirements (coming from the
various application areas), high-level specification techniques (such as
stochastic Petri nets, stochastic activity nets, dynamic queueing networks and
object-oriented techniques), implementability of conceptual models,
implementation aspects of MRM generation techniques and existing software
tools for performability modelling and analysis.


SOCIAL PROGRAMME

Tuesday, 15th September 7.00pm

Civic Reception at the Edinburgh City Chambers


Wednesday, 16th September - Optional Excursions

Murder and Mystery Tour
Whisky Tasting


Thursday, 17th September 7.00pm for 7.30pm

Conference Dinner at the Royal College of Physicians

                                   --------

PROGRAMME COMMITTEE:
        Ian Akyildiz, Georgia Tech, USA
        Heinz Beilner, University of Dortmund, Germany
        Maria Calzarossa, University of Pavia, Italy
        Rosemary Candlin, University of Edinburgh, UK
        Giovanni Chiola, University of Torino, Italy
        Blaine Gaither, Amdahl Inc, USA
        Gunther Haring, University of Vienna, Austria
        Peter Harrison, Imperial College, London, UK
        Peter Hughes, Bell Northern Research (Europe), UK
        Peter King, Heriot-Watt University, UK
        Anthony Krzesinski, University of Stellenbosch, RSA
        Raymond Marie, IRISA, France
        Ramon Puijganer, University of Balearics, Spain
        Herb Schwetman, MCC Inc, USA
        Guiseppe Serazzi, Politecnico di Milano, Italy
        Connie Smith, L & S Computer Technology, USA
        David Thomas, BT Ltd, UK
        Alex Wight, University of Edinburgh, UK

Organisation:

Local Arrangements: Jane Hillston, ([e-mail])
                    Dept. of Computer Science, Univ. of Edinburgh, UK

Sponsorship & Exhibitions: Peter King, ([e-mail])
                           Dept. of Computer Science, Heriot-Watt Univ., UK

Tutorials: Nico van Dijk, (fax: [phone])
           Dept. of Econometrics, Univ. of Amsterdam, Netherlands.


                                   --------
Travel Arrangements

Air     Edinburgh International Airport is less than 20 minutes from the city
        center and provides access to a worldwide network of international
        flights. There are 26 return flights each day to London provided by
        British Airways, British Midland and Air UK (Gatwick), in addition to
        regular services to Birmingham and Manchester.  Direct air links to
        New York, Chicago and Boston, together with many main European cities
        are provided from Glasgow Airport, one hour's drive from Edinburgh.

Rail    Edinburgh benefits from an extensive network of rail services from
        London and other principal UK cities.  High speed trains operate on
        the London route with a journey time of 4 hours to Waverley Station,
        in the heart of the city, a short walk from the Scandic Crown hotel.
        Inter City Sleeper services are provided on most routes.

Road    Express coach services are available to and from all major UK cities,
        operating on a comprehensive motorway or trunk road system.

                                   --------


The conference fee includes attendance at all sessions of the conference;
refreshments and lunch each day; a local copy of the proceedings; attendance
at the civic reception and the conference dinner; car parking at the hotel.
The student conference fee does not include the conference dinner.

Additional tickets for the conference dinner, price 35 pounds, will be
available on arrival.

Delegates registering before 14th August can take advantage of a preferential
rate.

Cancellation before 14th August will be eligible for 100% refund of all fees.
Subsequent cancellation, up to 4th September, will be eligible for 75% refund.
After that date no refund will be possible.  Delegate substitution will be
acceptable at any time.



To register please detach and complete the form below and return it to:

        Mrs Edith Field
        UNIVED Technologies Ltd.
        University of Edinburgh,
        16, Buccleuch Place,
        Edinburgh EH8 9LN
        SCOTLAND.
        [e-mail]

        fax: [phone]

8<---8<---8<---8<---8<--- please detach and print 8<---8<---8<---8<---


Name ____________________________________________

Company/Institute________________________________

Address__________________________________________

_________________________________________________

_________________________________________________

_________________________________________________

Telephone________________________________________

Email____________________________________________

Signed___________________________ Date___________


CONFERENCE REGISTRATION
                        Before 14/8/92        After 14/8/92

Academic Delegate         275 pounds           295 pounds    ______ pounds

Non-academic Delegate     325 pounds           345 pounds    ______ pounds

Student Delegate          150 pounds           170 pounds    ______ pounds

(Students will be required to bring some form of identification of
 certification of student status.)


TUTORIAL REGISTRATION

Which tutorial(s) would you like to attend? (Please tick)

A ___    B ___    C ___    D ___    E ___    F ___

Tutorial fee includes lunch and refreshments during the day, tutorial notes
of the tutorial attended and attendance at the civic reception.

Half day tutorial attendance  50 pounds

Full day tutorial attendance  80 pounds

                                                           ______ pounds

Do you require vegetarian meals?    Yes/No      ______

Accommodation has been reserved in the Scandic Crown Hotel and in Pollock
Halls, the University's major residence complex in the south of the city,
approximately 20 minutes walk from the Scandic Crown.

Scandic Crown Hotel:

64.75 pounds per person per night (B&B)
             single or double room                         _________ pounds

59.00 pounds per night for accompanying
             spouse sharing double room                    _________ pounds


Pollock Halls:

21.75 pounds per person per night (B&B)
             (single rooms)                                 _________ pounds


Arrival Date _____________    Departure Date _____________


                                                TOTAL COST  __________ pounds

Cheques, Money Orders and Bank Drafts in Sterling
payable to UNIVED Technologies Ltd.





------------------------------


Subject: [DEPARTMENTS]


------------------------------


Date:    Sun, 30 Aug 92 22:38:09 GMT
From: [e-mail]
Subject: E-S3 Vol.1, No.8, Part Two
X-St-Vmsmail-To: @AB

The following sample issue of our electronic magazine, "E-S3",
covering selected topics about computer modeling and simulation,
is sent to you with the compliments of the publisher of the
technical journal SIMULATION, the Society for Computer
Simulation, and John and Suzette McLeod, the Editors of
Simulation in the Service of Society (S3), a special section of
that journal.  If you do not care to receive future issues please
type REPLY -- cancel.  Let's not clutter up our E-mail with "Junk
Mail".
 -----------------------------------------------------------------

                  E-S3  Vol. 1, No. 8, Part Two

                based on the August 1992 issue of
              "Simulation in the Service of Society"
John McLeod, Technical Editor     Suzette McLeod, Managing Editor
          8484 La Jolla Shores Dr., La Jolla, CA 92037.
                   E-mail: [e-mail]
                                *
                   S3 is a special section of
                           SIMULATION
                   the monthly journal of the
                 SOCIETY for COMPUTER SIMULATION
             P.O.Box 17900, San Diego, CA 92177-7900
            Phone: [phone] FAX: [phone]
                                *
[Copyright Notice: E-S3 is the electronically delivered version
of "Simulation in the Service of Society" which is a special
section of SIMULATION, a monthly technical journal of the
Society for Computer Simulation International. It may be
reproduced only for personal use or for the use of students. In
any case full credit must be given to the original source of
publication: SIMULATION 59:2, August, 1992.
  All rights  reserved, (c) 1992, Simulation Councils, Inc.]
 ----------------------------------------------------------------------

A DESIGNER DRUG AGAINST AIDS?

Herewith the edited version of a press release from the
University of California/San Francisco on a paper delivered at
the February 1992 annual meeting of the American Association for
the Advancement of Science.

                                *

A University of California/San Francisco theoretical chemist,
Peter A. Kollman, Ph.D., Professor of Pharmaceutical Chemistry
at the University of California/San Francisco, has invented a
computer model widely adopted by drug companies to speed the
search for potential pharmaceuticals has improved the model and
used it to accurately predict the forces binding an AIDS virus
enzyme, called protease, to a molecule that disrupts the enzyme's
natural function.

The molecules under investigation are called protease inhibitors,
and they prevent the AIDS virus enzyme from fashioning the parts
needed to make a new virus from raw material provided by a human
host.

Although the inhibitors examined were not useful drugs, the
agreement of the model predictions with reality highlights the
growing power that researchers have to model the interactions of
biologically active molecules, and the promise of computer-
assisted drug design.

In computer-assisted drug design, researchers pool their
knowledge of biological structure and pharmaceutical chemistry --
and sometimes quantum physics -- to put together models that
more accurately describe the interactions of biological
molecules.

The most advanced computational techniques and computer graphics
capabilities are used to run the models.  The goal is to identify
molecules that will interact with disease vectors or toxins in a
way that limits the damaging impact of the invaders.

As knowledge grows, the use of molecular modeling in computer-
assisted drug design is steadily decreasing the amount of time
and money spent on trial-and-error approaches.

According to Professor Kollman, "In modeling you want to
represent enough of the known facts so that you can predict the
facts that aren't known yet."  Representing the known facts
requires a lot of power and valuable supercomputer time, but
ultimately can save pharmaceutical companies millions of dollars
spent on drug screening.  To run his model, Dr. Kollman uses work
stations and mini-supercomputers, and for most of the major
projects, a Cray Y/MP at the Supercomputer Center on the campus
of the University of California/San Diego.

Protein and DNA are "macromolecules" built up from hundreds or
thousands of smaller molecules.  The quest for the Holy Grail in
molecular modeling is to be able to predict the three-dimensional
structures of macromolecules, using as input only the knowledge
of the order in which their constituent building-block molecules
are linked together.

Although not so important in the trial-and-error approach,
knowledge of three-dimensional structure -- of the protein shell
encasing a virus, or of a macromolecule on the cell-surface of a
bacterium, for example -- is the foundation for computer-aided
drug design.

Agents of disease are like unwelcome guests that somehow got hold
of the house keys.  The idea behind inhibitor drugs is to stop
the invaders by luring them to the wrong house, where their keys
get stuck in the lock.  To predict a good design to trap an
invader, it helps to know the shape of the key and lock.

The determination of the sequence of amino acids in purified
protein, or of nucleotide base pairs in an isolated DNA molecule,
has become almost routine.  But the Holy Grail model must await
quantum leaps in computer power, and in the scientific
understanding of basic rules linking knowledge of amino acids "on
a string" to three-dimensional structure.

To design protein inhibitors, modelers ideally would like to know
the three-dimensional structure in some detail.  This is not
easy, but for pure protein crystals these structures can be
determined with a technique called x-ray crystallography, while
for smaller proteins in solution, nuclear resonance spectroscopy
can be used.

Once this structure is known it can be modeled, and the model
visualized on a screen.  Graphics do not provide quantitative
information, Kollman says, "But enable the chemist to use
intuition to tap into new ideas about how molecules fit
together."

Kollman's colleague Irwin D. Kuntz, Ph.D., Professor of
Pharmaceutical Chemistry at UC/San Francisco, has developed a
space-filling model in which proteins are represented as a series
of spheres of various sizes.  The shape of the space around the
protein is also modeled as a collection of spheres, and computer
programs determine which potential protein-binding molecules best
fit this "ball space."  The model scans standard chemical data
bases for potential inhibitors.

Kuntz and his colleagues used the model, called DOCK, to identify
an AIDS protease inhibitor which, though too toxic for therapy,
helped demonstrate the power of his approach and provided a lead
in the pursuit of a more effective inhibitor.

The search for drugs that act as protein inhibitors has often
focused on molecules called peptides, typically modified versions
of well-known molecules to which the proteins already bind.
However, peptides are often ineffective as drugs because they are
chewed up by the body's enzymes, and do not easily enter the
brain.  Programs such as DOCK enable researchers to search for
inhibitors in less well-charted waters.

Kollman's model, called AMBER, is aimed at gaining a more
refined understanding of the forces governing molecular
interactions when one already knows what kinds of inhibitors fit
the space, and needs to know which of them would be most
energetically favored to bind tightly.

Kollman is applying AMBER to the potential AIDS protein
inhibitors identified with Kuntz's DOCK model, focusing on a
limited number of molecules that are most important in predicting
how tightly AIDS protease will bond to the inhibitors.

He calls the approach molecular dynamics.  The atoms within
molecules flex and vibrate like balls connected by springs in
response to forces within the molecules.  Kollman models these
forces, as well as the forces of electrical attractions between
molecules, and the force necessary to maintain the molecules in
the liquid phase (called van der Waals interactions), to simulate
the structure and motion of the protein and its inhibitors.

The laws of thermodynamics favor low-energy states.  AMBER
explores many different shapes that macromolecules theoretically
might assume in interacting with other complex molecules, and
tries to identify ones which are energetically favored.

The most detailed versions of molecular models used by
theoretical chemists -- those which yield the most accurate
predictions of the strength of interactions formed between
molecules -- also incorporate the principles of quantum mechanics
to describe sub-atomic forces.  This approach requires even more
computer time than molecular dynamics, Kollman says.

"We could apply quantum mechanical methods to study the formation
and breaking of bonds in systems with only tens of atoms, but not
with hundreds or thousands."  Since there is not an infinite
supply of computer power available, Kollman explained, "We can't
know the forces and energies as precisely as you would like, and
we cannot try out all the conformational possibilities as
effectively as you would like."

This poses what Kollman calls the "local minimum problem" meaning
that of the many shapes an inhibitor might assume in binding to a
protein, there are usually multiple conformations that would have
favorable, low binding energies.  The trick is to devise a model
that will find the best.

"Imagine an egg carton where the troughs are of different depths.
With the wrong search strategy you might end up in the wrong
trough, a local energy minimum.  We use our dynamic model to go
over the dividers from trough to trough in order to find the
deepest."

Computer technology is now probably the biggest limit to
usefulness of molecular models, according to Kollman.  More
powerful computers are needed, he said, especially parallel-
processing machines capable of running many components of
molecular modeling programs simultaneously.  But better
mathematical and computational representations of molecular
interactions, called algorithms, will still be indispensable, he
says.

"Parallel processing means that faster algorithms will solve
their part of the program before slower ones.  If 90% of the
slowdown is solved, you still have only speeded up the process by
a factor of 10," he says, not enough to describe larger molecules
accurately.

Kollman's team also is focusing on creating a simpler but still
accurate algorithm to describe the interactions between molecules
and the water milieu in which they are dissolved.

"We want to save computer time by finding ways to represent water
without including calculations for every water molecule,"
Kollman explained.

UC/SF researchers led by Robert Langridge, Ph.D., director of the
UC/SF Computer Graphics Laboratory, have pioneered the computer
imaging of biological molecules, and many UC/SF senior scientists
with expertise in computer-assisted design and structural
chemistry are now working together in a major effort to identify
potential AIDS drugs.

[The December 1990 issue of S3 carried an article entitled
"Empiricism vs. Understanding" which described the efforts of
Agouron Pharmaceuticals Inc. to develop a drug for a specific
purpose -- to design a key to fit a lock of unknown design. JM]

                       *        *        *

More on Noise

In the January 1992 issue of SIMULATION a technical note by
Granino Korn was published under the heading "Noise."  Comments
on the note by Robert Kinnison, and Granino's reply, appeared in
S3 for February 1992.  Here we publish further remarks, by Turkan
Gardenier.

Dear John:

My comments on the article by Granino Korn can be summarized as
follows.

(1)  The idea of "noise" has been and is of interest to
statisticians.  In fact, Box-Jenkins time-series analysis has an
essential component, that of modeling "white noise."

(2)  The author distinguishes between pseudorandom noise,
congruential noise, and shift-register-type noise in the first
paragraph.  This is stated in the first paragraph; the
distinction is not made clear to the reader, however.  The
statement "pseudorandom noise is not random: you can predict
future samples if you know sufficiently many (very many) samples"
is reminiscent of Box-Jenkins p, d, q components.  The
distinction between "statistically independent" and
"uncorrelated" is, again, reminiscent of the "first order
autoregression" in Box-Jenkins time-series.

(3)  I think the idea of getting the reader involved in thinking
about underlying components other than correlations of the "first
order," such as a first order transition matrix in a Markovian
approach, or a first order autoregression, is good.  The hardware
orientation for designing a noise generator with a knowledge of
"lurking components" is also good.  Yet, I think the author needs
to look into some of the literature in statistical time-series
analysis (e.g., Box-Jenkins) which defines and breaks down "noise"
components into short- and long-term determinants.

Turkan K. Gardenier, Ph.D.
U.S. Equal Employment Opportunity Commission


Enclosed with Dr. Gardenier's letter were abstracts of papers
presented at the session which she co-organized with William Eddy
(Department of Statistics, Carnegie-Mellon University) for the
1992 Annual Meeting of the American Association for the
Advancement of Science.  Herewith the session description as it
appeared in the AAAS program.

Statistical Modeling and Analysis Using Personal Computers

Microprocessors are gaining increased usage in scientific
settings ranging from medicine to military applications.  A
parallel effort in software development has brought enhanced
applications of artificial intelligence, user-friendly, menu-
driven systems; and the flexibility to branch into various modes
of analysis.  The advances mean the user must be educated
regarding data analysis and mathematical modeling.  For example,
scientific experimenters need to know if a linear regression
analysis is appropriate for the data at hand, need to graphically
display interrelationships among the input variables, and need
tools to track data over time.  This symposium will present
recent developments that address these issues.

And the abstract of Dr. Gardenier's own paper:

"Discrete time-series methods for monitoring data"

This talk will present a method for tracing the status of
successive observations over time using the Cumulative
Transitional State Score developed by the author.  Implementing
this procedure involves partitioning data into three discrete
categories (+1, 0, and -1) corresponding to "above normal,"
"normal," and "below normal" subdivisions.  This trinomial
partitioning is based upon an examination of prior data and
expert/clinical judgment.  A similar decision process is also
used in evaluating transitions over successive time-period
evaluations.  A scoring scheme based upon both structures is then
implemented in order to cumulate and graphically display
transitions in status between two specified time periods.

                       *        *        *



------------------------------




END OF SIMULATION DIGEST
************************