Thread View: comp.simulation
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Started by Moderator: Paul Fishwick
Fri, 13 Nov 1992 15:02
SIMULATION DIGEST V30 N2
Author: Moderator: Paul Fishwick
Date: Fri, 13 Nov 1992 15:02
Date: Fri, 13 Nov 1992 15:02
1128 lines
45943 bytes
45943 bytes
Volume: 30, Issue: 2, Fri Nov 13 10:01:17 EST 1992
+----------------+
| TODAY'S TOPICS |
+----------------+
[GENERAL INFORMATION]
Consulting for Simulation & Modeling
Learning Sciences Ph.D. Program
[NEW QUESTIONS]
Object Oriented Languages
MODSIM Problem
Graphical Tool for OOS
Combined Optimization and Simulation
[SOFTWARE]
ARS MAGNA: Robotics Simulator
[DEPARTMENTS]
Simulation in the Service of Society
* Moderator: Paul Fishwick, Univ. of Florida
* Send topical mail to: simulation@bikini.cis.ufl.edu OR
post to comp.simulation via USENET
* Archives available via FTP to bikini.cis.ufl.edu (128.227.224.1).
Login as 'anonymous', use your e-mail address as the password, change
directory to pub/simdigest. Do 'binary' before any file transfers.
* Simulation Tools available by doing above and changing the
directory to pub/simdigest/tools.
-----------------------------------------------------------------------------
Subject: [GENERAL INFORMATION]
------------------------------
From: Richard Freytag <freytag@seas.gwu.edu>
Subject: May I post Simulation consultant request?
To: simulation@bikini.cis.ufl.edu
Date: Mon, 9 Nov 92 13:35:23 EST
Cc: hull@aic.nrl.navy.mil (Kent Hull)
X-Mailer: ELM [version 2.3e PL11]
Content-Length: 676
X-Lines: 18
Simulation and Modeling expert needed. Consulting position, immediate opening
requiring 2 months at least. Require wide, extensive, and lengthy
practical experience with _commercial_ discrete time-step simulation and
modeling packages currently on the market. Does not require presence at
local office or extensive travel.
All inquiries welcome.
Reply by email to: freytag@seas.gwu.edu (Richard Freytag)
------------------------------
Newsgroups: comp.simulation
Path: usenet
From: jones@ils.nwu.edu
Subject: New Ph.D. Program
Sender: usenet@ils.nwu.edu (Mr. usenet)
Nntp-Posting-Host: mac87.ils.nwu.edu
Organization: institute for the learning sciences
Date: Mon, 9 Nov 1992 20:10:38 GMT
Apparently-To: comp-simulation@cis.ohio-state.edu
Content-Length: 2014
X-Lines: 43
T h e L E A R N I N G S C I E N C E S P h. D. P r o g r
a m
Preparing individuals for productive work and a high quality of life in
today's society is a complex challenge for schools and corporations. To meet
this challenge, Northwestern University has established a unique Ph.D. program
in the Learning Sciences. Its purpose is to advance the research and
development of innovative educational structures and technologies.
Research in the Learning Sciences is aimed at creating environments that offer
all students a rich variety of opportunities for learning to think effectively,
both within and outside of formal learning settings. Graduate student and
faculty research efforts are supported by a multimedia, networked computing
infrastructure and an unusual commitment to developing technologies that
function effectively within their intended settings.
The Learning Sciences is a synthesis of computational and social science
disciplines including artificial intelligence, cognitive and developmental
psychology, educational research, linguistics, computer science, anthropology
and fields that develop strategies for teaching complex subject matter.
Through research, field work and apprenticeships, the Ph.D. program will
prepare its graduates to assume leadership roles in advancing the scientific
understanding and systematic practices of learning and teaching.
Students are eligible for competitively-awarded multi-year funding. To qualify
for financial aid, candidates should apply by January 15, 1992. Applications
received after that date may be considered. Individuals with relevant teaching
experience or a strong academic background in a field related to the Learning
Sciences are encouraged to apply. For application materials or for further
information, contact:
Professor Roy Pea
Ph.D. Program Chair
The Learning Sciences
Northwestern University
1890 Maple Avenue
Evanston, IL 60201
phone: 708-491-8152
fax: 708-491-5258
email: jones@ils.nwu.edu
------------------------------
Subject: [NEW QUESTIONS]
------------------------------
Newsgroups: comp.simulation
Path: visix!moe
From: moe@visix.com (Maureen Yim)
Subject: Modsim II vs. C++
Sender: news@visix.com
Date: Sun, 8 Nov 1992 22:46:50 GMT
Reply-To: moe@visix.com (Maureen Yim)
Organization: Visix Software, Reston, Virginia
Keywords: Modsim II, C++, discrete event simulation
Hi, I'm interested in any opinions out there in regards to
object-oriented, discrete event simulation using Modsim II from CACI
versus C++. I have heard some engineers suggest that Modsim II has
problems with dynamic binding, and they are entertaining the idea of
jumping from Modsim II to C++, but I'm not convinced that have
considered all the implications that could arise. All opinions
appreciated.
moe
------------------------------
From: cnews@umr.edu (UMR Usenet News Post)
Newsgroups: comp.simulation
Path: cnews
Subject: read binary file containing structures and arrays with MODSIM
Date: Mon, 9 Nov 1992 21:17:31 GMT
Nntp-Posting-Host: next4.cs.umr.edu
Reply-To: matze@mcs213k.cs.umr.edu
Organization: University of Missouri-Rolla, Missouri's Technological University
Keywords: MODSIM, structures, arrays, files
Sender: cnews@umr.edu (UMR Usenet News Post)
Apparently-To: uunet!comp-simulation@uunet.uu.net
Content-Length: 831
X-Lines: 22
Hi there,
I have the following problem with MODSIM and C.
I need to read a binary file with MODSIM which was created with C. The file
contains simple integers, arrays of integers and arrays of structures.
I have no problem reading this file with C but I haven't found a way to
read this file with MODSIM.
If someone has any ideas of how to solve the problem or need more information
about the structures I use mail to matze@cs.umr.edu.
Thanks in advance.
Matt
--
Matthias "Matt" Mayer University of Missouri-Rolla
matze@cs.umr.edu Computer Science Department
"Scott me up, Beamy!" Missouri's Technological University
----> "OS/2 for the PS/2. Half an operating system for half a computer."
----> "Did you know that UNIX is a four-letter word?"
------------------------------
Newsgroups: comp.sys.sun.apps,comp.simulation,comp.sys.sun.wanted
Path: euas29c44!tmpmgg
From: tmpmgg@eua.ericsson.se (Mats Gunning)
Subject: Wanted: VisualisationTool
Sender: news@eua.ericsson.se
Nntp-Posting-Host: euas29c44.eua.ericsson.se
Reply-To: tmpmgg@eua.ericsson.se
Organization: Ellemtel Telecom Systems Labs, Stockholm, Sweden
Date: Tue, 10 Nov 1992 09:21:46 GMT
Apparently-To: comp-simulation@sunet.se
Content-Length: 1394
X-Lines: 38
Could anyone help me find a graphical tool suitable for modeling an
executing object oriented system?
My aim is to make an application that reads a detailed tracelist made
from an executing objectoriented communication system. From that list,
I want to graphically display every interesting event such as signals
in the net, object creation and deletion.
Because of the amount of information in the tracelist, I have to filter
it in a way the user dynamically decide.
For example if the system starts with an event that triggers 10 events
that triggers 20 events each that ....
This would soon become impossible to display, why the user should be able
to choose which branch(es) he/she wants to trace.
My plan is to split the problem in two parts, a module written by me in
C++ that filters the input, and a visualisation-module that I hope already
exist somewhere. The properties I want from the visualisation-module is
that it:
* Contains a model of the system entities.
* Can use arbitrary bitmaps to represent objects.
* Can read input from a file or socket and does appropriate actions.
* Reports events such as mouseclicks on an object to the filter module.
If anyone has seen a tool suitable for this purpose, I would be most
greatful for a mail to:
tmpmgg@eua.ericsson.se
Mats Gunning
Student at School of Computer Science at
Royal Institute of Technology, Sweden.
------------------------------
Date: Tue, 10 Nov 92 22:12:48 -0800
From: Patrick Vye <pvye@u.washington.edu>
Sender: pvye@milton.u.washington.edu
To: simulation@bikini.cis.ufl.edu
Subject: Combinatorial optimization and simulation
Content-Length: 502
X-Lines: 17
Hello,
I am looking for some pointers. I would like to find work that has
been dome using combinatorial optimization of policy alternatives
in conjunction with simulation.
I have a problem in which many discrete alternatives should be
evaluated in a continuous simulation. Any work that has been done
in discrete-event or continuous simulation would be helpful. Also
anything that talks about model validation problems given such a
situation would be very helpful.
Thank you very much.
Pat
------------------------------
Subject: [SOFTWARE]
------------------------------
To: comp-simulation@uunet.UU.NET
Path: not-for-mail
From: engelson-sean@CS.YALE.EDU (Sean Philip Engelson)
Newsgroups: comp.simulation
Subject: Abstract Robot Simulator available
Date: 6 Nov 1992 10:11:02 -0500
Organization: Yale AI Mobile Robotics Project
Distribution: world
Content-Length: 3308
X-Lines: 89
Now Available
~~~~~~~~~~~~~
ARS MAGNA
The Abstract Robot Simulator
Sean P. Engelson
Department of Computer Science
Yale University
ABSTRACT:
~~~~~~~~
AI planning research has historically operated in formal abstractions
of the real world. This approach was useful in discovering many
fundamental issues underlying planning; also, problems in simple
domains such as the blocks world can turn out to be surprisingly
difficult. Lately attention has turned to planning for more realistic
domains in which micro-world simplifying assumptions do not hold.
This shift of focus introduces a new problem of validation and
comparison of different planning theories and systems. A proper
domain for planning problems must be realistically complex but also
simple enough to support controlled experimentation.
To address these questions, we developed the ARS MAGNA robot
simulator. The simulator provides an abstract world in which a
planner controls a mobile robot. Mobile robotics is a particularly
apposite domain since it is a major application area for AI planning
techniques. ARS MAGNA's environment and robot models are based on
current robotics research, so that the domain is reasonably realistic.
At the same time, we abstracted away from many (though not all)
real-world details of kinematics and motor control. Experiments may
be controlled by varying global world parameters, such as perceptual
noise, as well as building specific environments in order to exercise
particular planner features. The world is also extensible to allow
new experimental designs that were not thought of originally. The
simulator also includes a simple graphical user-interface which uses
the CLX interface to the X window system.
DOCUMENTATION:
~~~~~~~~~~~~~
Version 1.0 of the ARS MAGNA simulator is documented in Yale Technical
Report YALEU/DCS/RR #928, "ARS MAGNA: The Abstract Robot Simulator".
This report is available as a Postscript(tm) file both in the
distribution and separately via ftp as pub/TR/tr928.ps.Z. Hardcopies
are available from Yale University (Paula Murano, murano@cs.yale.edu).
Any and all comments would be most welcome.
AVAILABILITY:
~~~~~~~~~~~~
ARS MAGNA can be gotten by anonymous ftp from ftp.cs.yale.edu, as
ars-magna.tar.Z in the pub/nisp directory, as follows:
% ftp ftp.cs.yale.edu
Connected to dept-gw.cs.yale.edu.
220 ra FTP server (SunOS 4.1) ready.
Name (ftp.cs.yale.edu:engelson): anonymous
331 Guest login ok, send ident as password.
Password:
230 Guest login ok, access restrictions apply.
ftp> cd pub/nisp
250 CWD command successful.
ftp> bin
200 Type set to I.
ftp> get ars-magna.tar.Z
200 PORT command successful.
150 Binary data connection for ars-magna.tar.Z (128.36.17.10,1220) (528589 bytes
).
226 Binary Transfer complete.
local: ars-magna.tar.Z remote: ars-magna.tar.Z
528589 bytes received in 7.4 seconds (70 Kbytes/s)
ftp> quit
221 Goodbye.
% uncompress ars-magna.tar.Z
% tar xf ars-magna.tar
%
Installation instructions are in the file Installation.readme. The
simulator is written in Nisp, a macro-package for Common Lisp. Nisp
can be retrieved in the same way as the simulator.
--
Sean Philip (Shlomo) Engelson
Yale Department of Computer Science
Box 2158 Yale Station
New Haven, CT 06520
------------------------------
Subject: [DEPARTMENTS]
------------------------------
Date: Thu, 5 Nov 92 19:27:14 GMT
From: mcleod@Sdsc.Edu
Subject: E-S3 Vol.1 No.10
Content-Length: 31444
X-Lines: 712
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. 10
based on the Otober 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: mcleod@sdsc.bitnet
*
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: (619) 277-3888 FAX: (619) 277-3930
*
[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 59:4, October 1992.
All rights reserved, (c) 1992, Simulation Councils, Inc.]
----------------------------------------------------------------------
MISSION EARTH
The Inspiration
Under the heading REPORT in this column in the September
issue we wrote "After a lively and progressive discussion, kicked
off by Ben Clymer giving excerpts from his excellent and
perceptive Position Paper ... some facts became clear ..."
The following is an update of Ben's paper, which was
instrumental in launching what has become SCSI's project MISSION
EARTH, our effort to better understand, and thus be in a better
position to alleviate, our many environmental problems.
----------------------------------------------------------------
"Specifications for
Simulations in Planet Planning"
by
A. Ben Clymer
32 Willow Drive, Ste. 1B
Ocean, NJ 07712
John McLeod, founder of The Society for Computer
Simulation, has called upon simulationists to address seriously
the question of how to use simulation as the preferred tool for
planning the saving of our race and planet. This Panel and its
associated position papers constitute just one step toward that
goal.
This paper is an extension of the author's position
statement for John's session at the 1992 SCSC. It includes a
description of the SCS Technical Activity called Mission Earth
and its plans for action on behalf of mankind and the planet's
other organisms. Included in the references are the author's
previous publications relevant to Mission Earth, which indicate
his long and broad interest in the problem.
Many writers, too numerous to cite, have pointed with
intense alarm to the desperateness of the situation in which we
find ourselves globally. The planet is in distress. We have
despoiled our environment totally, in scope if not yet in amount.
Already the consequences of our irresponsibility are
grave, and they are increasing rapidly in severity. The problem
is compounded by the don't care attitude of many people. One can
easily extrapolate to the planet becoming uninhabitable for Man.
Not only that, but the human population is fast becoming grossly
excessive for the space and resources even now available. We are
leaving to future generations a highly undesirable, if not
impossible, problem to deal with in order just to live.
There is a substantial history of previous attempts to
put things right through simulation studies. The groundbreaker
was Jay Forrester's 1970 proposal to the Club of Rome to simulate
man's activities over the entire world and over a long time into
the future (Meadows et al. 1972, 1973, 1974). Subsequent
simulation studies by others elsewhere (notably Mesarovic and
Pestel) since then have added variables, details, and size to the
MIT model. However, the main outcome seems to have been
expression of an "ain't it awful" feeling, with minimal regard
being given the matter and with virtually no positive action
being taken by the hierarchy of governments. It has been
difficult for observers to entertain any hope of victory by Man
over himself.
A. Mathematical Aspects
1. Purposes of Simulation for Planet Planning
There are numerous purposes for which simulation can and
should be used in planet planning including the following:
1. To learn more about the system. There is much that we
do not know, to the point that some organizations abandoned their
attempts at world simulation (D. H. Meadows 1985).
2. To get initial conditions for simulation runs by
simulating the recent past. These runs also can be checked
against available historical and current data as partial
validation of the model.
3. To educate all personnel about the system and plans.
These persons include managers on all levels of the global
hierarchy of government and environmental management,
simulationists with all levels of skill and experience,
journalists, the public, etc.
4. The main purpose of simulation is to try out a large
variety of plans that are being considered. The simulations
include an evaluation of all quantities that are involved in
judging each plan.
5. Simulations are needed to provide detailed
documentation of plans that survive the evaluations. The results
will provide accountability for the decision makers.
6. The same plan can be evaluated for different times of
initiation, in order to see the costs of delay. Then urgencies of
actions will be known.
7. Simulations can be used to determine the sensitivities
of important results of various details in the system or in
plans. Then one can decide when enough improvement of accuracies
of input data has been done.
8. Simulations can be tested against particular data to
identify where knowledge of the system model is inadequate.
Simulations can uncover ignorance.
9. Simulation can be the inner forward path of complex
optimization loops, as explained next.
2. The Overall Optimization Problem
The overall problem of planet planning is incredibly
complicated. It is hierarchical, which makes it necessary for
each plan to have essential content in every echelon of the
hierarchy. It is long-term, which requires that every plan be
extended many years into the future. It has a multitude of
aspects that interact, such as human population, environmental
integrity, ecological stability and diversity, economics,
political concerns on every level of government, quality of life
for humans and other species, sustainability against disturbances
not under control, etc.
It is an optimization problem, which requires that a
hierarchy of value functions be designed and argued through to
acceptance. It is an expensive undertaking for which no political
entity is prepared to pay its share. It involves constraints,
such as finite amounts of resources.
It is a global problem, which requires that many models
be developed on a global scale. It is a global problem also in
the sense of having to divide up the simulation work among many
nations having different languages, values, etc. There is a
rapidly approaching deadline for completion of study and
planning, after which only minor battles, if any, can be won.
Really, in the light of past undertakings by cooperative
simulationists and governments, it is too much for us. However,
the alternative is progressive and rapid extinction. Will
realization of the need cause an adequate response by mankind?
One way to look at the problem is that of Peter
Seligmann, who speaks of the "nexus between people and nature", a
network to be augmented and perfected by us in the form of
control systems. It will protect nature and people.
3. Input Data Needed
A few key kinds of data will be mentioned here. One is
the kind of details that go into such composite indices as the
Gross National Product. The GNP should not be used at all,
because it does not reckon from a broad enough standpoint. For
example, it does not consider the costs due to ravaging of the
environment, using up scarce resources, etc. New indices need to
be developed.
The following is a classification of most of the
variables of concern:
1. Populations: initial conditions; births, deaths, and
migrations
2. Ecosystems: status of species populations and
environmental variables
3. Atmosphere: composition input rates, chemical
kinetics, radiation throughputs
4. Natural resources: absolute inventories, costs of
progressive recovery
5. Materials: matrix of fluxes through industry,
pollutants generated by industry
6. Food: production distribution, soil conditions, animal
and fish availabilities
7. Fresh water: pollution processes
8. Ocean: composition, movements, atmospheric coupling
4. Final Steady State Conditions Desired
desired other than that an ultimate optimum state of the earth be
reached by a given date. Granted that some desideratum more
sophisticated than that will be wanted in the long run, this end
condition is a good enough one for the sake of the present
discussion.
The earth state is described by geographical hierarchies
of many variables: populations, energy usages, remaining natural
resources, quality of life, etc. The one most often discussed and
perhaps the most important is total world population and its
hierarchical distribution. Usually it is coupled with the
intended date of achievement. Various world populations have been
suggested as sustainable: 2-3 billion (Ann and Paul Ehrlich), and
1-2 billion (Roderick Frazier Nash). These numbers, being much
lower than the present world population, might never again be
achievable.
5. Systems to be Simulated
There are many systems that need to be simulated with as
much coupling as can be handled. One possible breakdown of the
overall system would feature population, economics, resources,
pollution, and quality of life (Susan Merrow).
Another breakdown of the system for purposes of
simulation would feature land management, water management,
atmospheric management, and space management. The following
remarks indicate what should be included and what some of the
major problems are:
5.1. Land Management
Individual terrestrial ecosystems (forests, grasslands,
tundra, etc.) deserve to be simulated in their actual
surroundings. The notable problems include control of timbering
and mining, fires, acid rain and its effects, erosion,
desertification, fertilizer and pesticide usage, tilling
practices, results of commercial incursions, interaction with
rainfall, tree planting optimization, reductions in species
diversity, extinctions of varieties and species, protection of
rivers from nonpoint source pollution, etc.
5.2 Water Management
These simulations should be by individual water bodies
wherever feasible, using lumping elsewhere. Some of the
freshwater management problems are allocation among would-be
users, fish kills, purification requirements as related to
intended uses, ecosystems species diversity and health, pollution
prevention and cleanup, acid rain effects, effects of pollution
upon wildlife, consequences of losses of wetlands, etc.
Some of the ocean problems are pollution by ships and
shore-based discharges, major oil spills, rise of water level due
to global warming, ocean-atmosphere thermal and flow
interactions, beach dynamics and barrier island management,
distillation to obtain potable water, etc. There are serious
problems also with ground water, which suffers pollution from
solid waste dumps and sewage disposal, and which is by far the
largest reservoir of fresh water (hence deserving of the best
protection).
5.3 Atmosphere Management
The atmosphere too is in need of simulation studies to
evaluate such phenomena as local and global warming and/or
cooling by the effects of various gases, the industrial processes
producing those gases (including agricultural industry cow
belches of methane), the ozone layer kinetics, urban air
pollution (smog, brown air), weather and climate management (if
and when feasible), acid rain transport and chemistry, wind-borne
radioactivity, fate of solid wastes burned, atmospheric motions,
temperatures and chemical reactions as in weather prediction,
etc.
A separate list could be made of phenomena in the region
of the atmosphere but not directly associated with the gases
there, such as cancer-causing effects of electric power at
frequencies at or below 60 Hz (if indeed there are such effects),
ultraviolet light, X-rays, etc. Higher up, we should be worried
about the growing proliferation rate of space junk orbiting the
earth.
5.4 Other Hierarchies
There is no single hierarchy that can comprehend all of
the systems to be simulated. Many hierarchies will be useful.
One of the most important is the geographic hierarchy of
human population dynamics. It spawns the principal despoilers of
the planet. It is these creatures that destroy natural
ecosystems, kill each other and vast numbers of other creatures,
pollute the land and water and air, create gases that change the
properties of the atmosphere for the worse, use up critical
materials, waste energy, obtain energy from relatively
inappropriate sources, use lawyers to write laws and other
lawyers to find loopholes, reproduce at rates making populations
that overwhelm the possible production of food, without any
lasting or effective restraint by governments, reward criminal
behavior, buy governmental representatives, and otherwise also
are the worst "bad actors" in our world.
Other hierarchies that need to be simulated in detail are
the economic system (geographic hierarchy, and by industry, etc.,
including the causes and effects associated with greed and fear),
the world and national and state governments, natural resources
inventories (including estimated possible future substitutions),
industries (as users of energy and materials, and as generators
of products and pollutants), the hierarchy of laws worldwide and
its trends, the worldwide hierarchy of morality and ethics for
individuals and organizations, worldwide companies (each a
hierarchy having effects upon many other hierarchies), the
financial system (international loans and repayments, control of
currencies, research and demonstration projects, etc.), etc.
6. Simulation of Planet Planning
The process of analyzing, simulating, and planning planet
management deserves to be simulated in the interest of improving
the process. The planning of this work should answer the
questions raised by McLeod: who, for whom, do what, and who pays?
Perhaps the stickiest part is cost. Cost rises faster
than linearly with improvement of the system to be managed. Hence
the choice of a level of improvement and cost will have to be
debated and resolved. The question cannot be answered
satisfactorily in the absence of many simulations, each of which
includes a price tag found as part of the simulation. Debate
based on present knowledge is a waste of time.
Most Americans want to protect and improve the
environment. The US now spends less than 2 cents per dollar on
the environment.
One of the best ways to raise money for governmental
purposes is taxation of the people most concerned with the
problem to be fixed. "Tax policy is one of the most potent
instruments to move the world in an environmentally sustainable
direction" (Brown). Taxes can be used to encourage some actions
while discouraging others. In a given country the system of
taxation can be organized as a matrix of monies needed for groups
of purposes vs. groups of people targeted. The matrix is not
diagonal.
The hierarchy of tax matrices is just one element of
concern in planet planning. However, there is not complete
freedom in manipulating these matrices, as evidenced by the fact
that ". . . 61% oppose raising new taxes specifically targeted to
the environment", although they would be willing to get the money
by raising some existing taxes (Anon.)." 92% believe a balance
between environmental protection and economic development can be
attained. . . . Only 10% believe (environmental protection) . . .
has gone too far" (Anon).
B. Managerial Aspects
1. Philosophy
1.1 Some Negatives
The present situation has stemmed largely from the
uncontrolled exercise of many human character defects throughout
the past.
1. Columbus and his men set the tone for the Spanish
conquest of the Americas by being individually greedy and lawless
robbers, murderers, rapists, etc., feeling that their superiority
(as they perceived it) entitled them to take their pleasure with
everything they found (Lopez). In addition there was no one to
stay their hand. This is the behavior of many people when they
consider punishment to be unlikely. It is the age-old
exploitation of the weak by the strong.
2. Even today in every country we have a "dysfunctional
civilization." That "civilization" has been having a collision
with the world, and we are just beginning to witness the response
of civilization to its own destructiveness (Al Gore).
3. Today's commerce shares the blame: "A large part of
the natural world has been damaged or destroyed by unregulated
commerce" (Ehrenfeld).
4. "We must quit being selfish, greedy, and violent"
(Wendell Berry).
5. ". . . there is no political concern more important
than putting a stop to the massive damage we are doing to the
earth and its atmosphere, and to accelerating population growth"
(Al Gore).
6. As we play God with our world we should try to
maintain a realization of our analogy to the Spaniards of the
1500's in the New World.
1.2 Some Positives
We need to be very choosy about the type of stewardship
that we give our world. Our record with aborigines and their
environments has been poor, starting with well-intentioned
missionaries and continuing with business men. To be guided by
ecologists would be mostly good for ecosystems and perhaps
peoples, but there could be an unreasonable price. We need to be
responsible in the eyes of all parties.
We must try to restore some of the balance between the
welfare of society and the health of the planet (Peter
Seligmann). Seligmann feels that "the only route to conservation
is through understanding how people can respect and live
harmoniously with nature". Again, in the words of Aldo Leopold,
"... the earth is a community to which we belong, not a commodity
it is our privilege to exploit" (quoted by Wallace Stegner).
Some special people must lead the way. According to Al
Gore, "... free men and women who feel individual
responsibility for a particular part of the earth are, by and
large, its most effective protectors, defenders, and stewards."
The publishers of and contributors toward ORION and other
conservation magazines are "... a dedicated group of people
working toward a new, deeper relationship to the land and its
inhabitants" (Charles Grayson). However, many more people will be
needed, notably in our field of simulation. In addition, "We have
to convert concerned individuals into environmental activists"
(Brown). We must preach to all the necessity of biophilia (the
love for all living things and their environment) (Lopez).
2. Hierarchies of Organizations Needed
An organized and structured plan is needed for executing
the work of planet simulation. One trouble is the large number of
organizations that should be involved in some way: the United
Nations, governments on every level, universities and research
institutes, ecosystem management organizations, financial
institutions, etc. The solution must tie them together in ways
that will make for acceptable cooperation and productivity. No
single hierarchy can accommodate them.
Undoubtedly universities will have to do the lion's share
of the modeling and simulation. However, they will require
outside funding from a variety of types of sources: grants from
their own governments on every level, grants from financial
institutions such as the World Bank, project support by
industries concerned, token payments from countries unable to
contribute otherwise, etc. Some support might be possible from
the nonprofit organizations which are defending the environment,
seeking to throttle population increase, etc., with funds
provided by individual members not otherwise coupled into the
problem. National and state laboratories can cooperate.
Industrial laboratories can help too.
It will be important to simulate every square foot of the
earth one way or another. There will inevitably be duplications
and overlaps, but there must not be gaps left uncovered, either
geographically or functionally.
3. Management of Ecosystems
Each ecosystem needs to be simulated as a whole, embedded
in its surroundings. Endangered species are especially important
elements. Protection of the ecosystem from all known threats
should be simulated. War is the worst threat to any ecosystem
(Frederik Pohl), and wars are always countable in the dozens
around the world. All "bad guys", such as poachers, need to have
their hands tied, down to some maximum allowable probability that
their actions will be disastrous. Slow demise of an ecosystem
from rim inward due to edge effects must be studied and plans
devised to oppose such loss.
Ecosystems might always be lost due to imperfect
management. If one fails, then any industry which had been
dependent on it must be phased out or moved. Thus lumbering must
be closed down on a forest ecosystem that has been too gutted to
continue or to be renewed as a forest. Likewise, commercial
activities in a National Park need to be limited, or shut down if
legal limits on such activities are exceeded by illegal means,
such as corruption of officials.
"Americans are relatively content with the amount of wild
or natural areas available for their use" (Anon.). Frederik Pohl
would stop allowing changes in land use, especially in the
direction of development. If such a change were suddenly imposed,
it would wreak havoc with such industries as construction and
real estate, but the time must come when limits are actually
imposed and enforced, however gradually.
Tropical forests have been the object of several
constructive suggestions. One is to establish extractive reserves
(i.e., forest setasides which can be worked nondestructively for
fruits, rubber, nuts, medicinals, button materials, fibers,
etc.). Another is agroforestry, in which special agriculture is
practiced within and without damage to the forest. Another is the
general category of sustainable development, in which nothing is
destroyed or used up while commercially valuable materials are
taken out. In all of these cases the natives are an excellent
source of information about uses of natural materials. In all of
these cases it is important to reward those peoples living in the
forest by means of an equitable share of profits.
C. Conclusions
1. The need is for about two orders of magnitude more
effort than will actually be expended, even with Man's best
efforts to organize for an emergency.
2. The Society for Computer Simulation should take the
lead in promoting and guiding the effort.
3. The key tool in support of planet management is
simulation.
4. The simulations required must encompass several
hierarchies of systems, many hierarchies of proposed plans, and
an overall optimization loop (for which the value function must
be decided upon early on).
5. The whole world of peoples must become involved to
various degrees and in various ways.
6. Most of the needed simulations must be developed
almost from scratch. Much basic information is unknown. However,
simulation is an excellent way to identify and correct ignorance.
7. We must keep in mind the alternative.
8. The failure phenomena that have been studied and
analyzed by William Livingston are sure to crop up in the larger
simulation efforts, especially those involving several
organizations.
D. Actions by SCS
SCS, the Society has taken some positive steps toward fulfilling
its needed role on behalf of the world.
1. Technical Activity, Mission Earth
A Technical Activity called Mission Earth has been created under
the leadership of Zoran Ilic. By virtue of this responsibility
Zoran is an Associate Vice President of SCS. The plans for this
Activity include the following.
* Develop standards for hierarchies of global and other
large models, simulations, and simulation run campaigns. Specify
to the maximum feasible extent the technologies and techniques
that should be used. A committee within the Activity will be
needed.
* Provide forums, at least quarterly, at which
simulationists, scientists, and planners can communicate with
themselves and each other. It is intended that each SCS
conference henceforth will include a portion devoted to Mission
Earth. Ben Clymer will head up this effort, which will be carried
out by a permanent committee.
* Monitor and search the literature for work of interest
to Mission Earth. Disseminate it through appropriate channels. A
whole team will be needed for this effort.
* Find and communicate with the simulationists,
scientists and planners now engaged in studies of concern to
Mission Earth, or who might well be. Extend and strengthen the
communication network among them. John McLeod will be doing some
of this through his publication "Simulation in the Service of
Society" and other channels. John has brought in Dick Chadwick,
of the University of Hawaii, who has many important contacts in
political science and global and regional simulation around the
world. Perhaps the McLeod Institute could be brought in as a
player, especially since it is growing worldwide and is respected
in academia.
* The next meeting of the Technical Activity (Mission
Earth) will be at the Western Simulation MultiConference in San
Diego in January 1993. All who are interested are invited to
attend, join up, and participate henceforth. The Activity will
meet at each major SCS conference.
* Financial support is being solicited for the Activity.
The expenses of the Activity are estimated to be much higher than
those of the other Activities now in existence.
2. Plans for Conferences
* Winter Simulation Conference, December 1992. There is a
possibility that a presentation will be made concerning the
applications of discrete event simulation and combined
(continuous and discrete event) to global problems, particularly
in the softer sciences, although it is very late to be trying.
* Western MultiConference, January 1993. Places in the
program are currently being negotiated. It is late for this one
too. This paper might be presented and discussed at length.
* Simulation MultiConference, April 1993. If a program
committee can be recruited in time, an attempt will be made to
develop a full conference or track for Mission Earth. Also, a
paper could be written to span the gap between "emergencies" and
the long-term global daddy "Emergency" of them all, for
presentation at the Emergency Management Conference.
* Summer Computer Simulation Conference, July 1993. A
full Group is intended for Project Earth. By then it should be
possible to report major progress by the Activity and bring in
many participants as authors and panelists.
* European 1993: There is an SCSI conference in November
1993 that might be suited to bringing together European
participants in Mission Earth. It will be discussed with the
European Office. A presentation could be made by an American
participant.
REFERENCES
Anon., "Natural Resources: Can They Be Saved?" Golf, July 1992,
pp 12-15.
Berry, W., see Stegner
Brown, Lester R., "Worldwatcher's Warning," World Monitor, May
1992, pp 18-20.
Clymer, A. Ben and R. S. Davidson. "The Desirability and Applica
bility of Simulating Ecosystems" in Annals of the New York
Academy of Sciences, January 1966, 128, 3, pp 790-794.
Clymer, A. Ben. "The Modeling of Hierarchical Systems." Keynote
Address, Proceedings of Conference on Application of Continuous
System Simulation Languages, June 1969, pp 1-16.
Clymer, A. Ben. "The Hierarchical Approach to Public Problem
Simulation" in SIMULATION, August 1970, pp 50-54.
Clymer, A. Ben and L. J. Bledsoe. "A Guide to the Mathematical
Modeling of an Ecosystem" in Simulation and Analysis of Dynamics
of a Semi-Desert Grassland, Range Science Department, Science
Series No. 6, Colorado State University, December 1970, pp I 75-
99.
Clymer, A. Ben. "Next Generation Models of Public Systems" in
Simulation Councils Proceedings, 1, 1, January 1971, pp 115-134.
Patten, Ed., Systems Analysis and Simulation in Ecology, 2,
Academic Press, 1972, pp 533-569.
Clymer, A. Ben and J. C. Burr, "Air Modeling in Ohio EPA" in
Proceedings of Conference on Environmental Modeling and
Simulation, U.S. Environmental Protection Agency, Cincinnati,
April 1976.
Clymer, A. Ben and R. G. Duffy. "Water Modeling in Ohio EPA" in
Proceedings of Conference on Environmental Modeling and
Simulation, U.S. Environmental Protection Agency, Cincinnati,
April 1976.
Clymer, A. Ben. "Simulation of Living Systems Then, Now and When"
in SIMULATION, August 1990, pp 97-102.
Clymer, A. Ben. "Simulations of the Environment" in Proceedings
of Simulation MultiConference, Society for Computer Simulation,
1991.
Ehrenfeld, D., "Raritan Letter," Orion, Summer 1992.
Gore, A., "Interview by Jordan Fisher-Smith," Orion, Summer 1992.
Grayson, C., Letter, Orion, Summer 1992.
Livingston, W. (1990), Friends in High Places, F.E.S. Ltd.
Publishing, New York.
Lopez, B. "The Rediscovery of North America," Orion, Summer 1992,
pp 10-16.
Meadows, D. H., et al. (1972), The Limits To Growth. Universe
Books, New York.
Meadows, D. L., and D. H. Meadows (1973), Eds., Toward Global
Equilibrium: Collected Papers. Wright-Allen Press, Cambridge, MA.
Meadows, D. L. , et al. (1974), Dynamics of Growth in a Finite
World, Wright-Allen Press, Cambridge, MA.
Meadows, D. H. (1985), "Charting the Way the World Works,"
Technology Review, Feb.-Mar., pp 54-63. (Includes a table of
information about 20 global models.)
Merrow, S., see Stegner.
Nash, R. F., see Stegner.
Pohl, F., see Stegner.
Seligmann, P., see Stegner.
Stegner, W., "Now If I Ruled the World," Sierra, May-June 1992,
pp 114-142.
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END OF SIMULATION DIGEST
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