HDTenEightyP/NetNews huggingface dataset:
From: shanks@saifr00.cfsat.honeywell.com (Mark Shanks)
Newsgroups: comp.human-factors
Subject: Re: Am I being turned into a handicapped programmer?
Date: 7 Oct 92 13:58:11 GMT
Article-I.D.: saifr00.1992Oct7.135811.14919
Organization: Honeywell Air Transport Systems Division

In article <1992Oct7.072030@eklektix.com> rcd@raven.eklektix.com (Dick Dunn) writes:

> I suspect (and various others corroborate the suspicion) that the
> incidence of left-handedness among serious computer users is as much
> as twice that of the general population.
>
Mr. Dunn has an interesting point that I also have observed. I hate to
obscure the gist of his article, but has anyone got figures for the
percentage of left-handed "power users", software engineers, or, for
that matter, engineers in general?

Mark Shanks
Principal Engineer, 777 Displays
shanks@saifr00.cfsat.honeywell.com
Newsgroups: comp.human-factors
From: robert@charon.jpl.nasa.gov (Robert Angelino)
Subject: Recommendation for a good HCI book...
Reply-To: robert@triton.Jpl.Nasa.Gov
Organization: Jet Propulsion Laboratory, Pasadena CA
Date: Mon, 12 Oct 1992 18:45:45 GMT

That's Human Computer Interaction...

thanks


-robert
From: jcook@mumble.cs.Colorado.EDU (Jonathan Cook)
Subject: Re: CD case design problem
Organization: University of Colorado, Boulder
Date: Fri, 16 Oct 1992 21:04:02 GMT

In article <1992Oct16.164044.23687@bcrka451.bnr.ca> mennie@bcrki39.bnr.ca (Bill Mennie 3-4473) writes:
>
>Another problem is that the case has extremely sharp corners.  It is
>VERY easy to scratch a CD as you are putting it into the case.
>
>
>Cheers,
>
>Bill
>

Well, you see, making a CD which doesn't contact moving parts, which
means it doesn't wear out, means loss of $$$ to the record companies;
so what better way to solve this than to make a CD case out of a
material HARDER (in the chemistry sense) than the CD - a harder
material always scratches a softer one. 

Simple greed is easy to understand :-(

Jon.

Xref: sparky comp.theory:2190 sci.math:13212 sci.math.symbolic:2718
Date: Thursday, 15 Oct 1992 01:42:33 CET
Newsgroups: comp.theory,sci.math,sci.math.symbolic
From: inemes@risc.uni-linz.ac.at (Istvan Nemes)
Distribution: world
Organization: RISC, J.K. University of Linz, Austria
Subject: Re: Recurrence relations

In article <1992Oct13.214306.2605@babbage.ece.uc.edu> dsims@leo.ece.uc.edu
(David Sims) writes
>Does there exist software for finding a closed form expression given a
>recursive function?
--
ethanb@ptolemy.astro.washington.edu (Ethan Bradford) mentiones maple's
rsolve() function. There is available a similar function also in Mathematica:
RSolve, based on the method of generating functions for solving recurrence
relations.
-- Istvan Nemes
Newsgroups: comp.theory.self-org-sys
From: mroussel@alchemy.chem.utoronto.ca (Marc Roussel)
Subject: Re: how many generations of "human" DNA
Organization: Department of Chemistry, University of Toronto
Date: Thu, 8 Oct 1992 14:13:20 GMT

In article <41323@imag.imag.fr> bessiere@imag.fr (Pierre Bessiere) writes:
>The order of magnitude of the number of nucleotides [in the human
>genome] is, therfore:
>3 x 3 10^2 x 10^7 = 9 x 10^9
[...]
>The order of magnitude of the number of theoreticaly different human
>being is : 4 ^ (9 x 10^9) let say to simplify 2 ^ (10 ^ 10).

     There is something badly wrong with this analysis.  We can't
randomly select all the bases and wind up with something living, never
mind human.  I have heard that the variability among human DNA is less
than 1% (much less?).  At most then, the number of possible genetically
different humans is 2^(10^8).  However, even this number must be too
large.  In most cases, it might be perfectly all right to change a single
base here or there, but multiple changes in the same gene might lead to
nonviable organisms.  This is becoming interesting.  Does anyone have
any idea of how many substitutional degrees of freedom human DNA has in
its current state?  I realize that this is a hopeless question to answer,
especially since it only captures part of the potential variability;
insertions and deletions are also possible and these would tend to
inflate the number of possible genetically different humans.

				Marc R. Roussel
                                mroussel@alchemy.chem.utoronto.ca
From: bessiere@imag.fr (Pierre Bessiere)
Newsgroups: comp.theory.self-org-sys
Subject: Re: how many generations of "human" DNA
Date: 8 Oct 92 10:47:08 GMT
Organization: IMAG Institute, University of Grenoble, France

In article <1992Sep20.223336.9996@leland.Stanford.EDU> ledwards@leland.Stanford.EDU (Laurence James Edwards) writes:

>Does anyone have a rough estimate of how many generations have transpired
>from the time of our earliest sexually reproductive ancestors (I'm talking
>about very simple organisms here) to the present? I'm just looking for
>something within a few orders of magnitude.

This is a very difficult question.
However, if we estimate a human generation to 20 years, it means that
there are 50000 human generations each million of years.
Hence, the order of magnitude of human generations is 10^4 may be 10^5
depending on what you call "human".
The number of preceding "non human" generations seems to me very difficult 
to estimate. However, it's a very interesting question indeed.

>Also, approximately how many guanine, adenine, cytosine, and thymine
>bases are there in the human genome? How many genes? How about for
>some typical very simple organism that is sexually differentiated?

This a much simpler question.
4 possibilities (as you said) for the nucleotides: G, A, C, T
That leads to 64 possible codons. Each codons is made of three nucleotides.
The order of magnitude of the number of codons per gene is 3 10^2.
The order of magnitude of the number of genes per chromosome is 10^6.
The order of magnitude of the number of genes per human being is 10^7.
The order of magnitude of the number of nucleotides is, therfore:
3 x 3 10^2 x 10^7 = 9 x 10^9
The order of magnitude of the number of nucleotides in E. Coli, a very simple
unicellular organism is 5OO hundred times left than for human being.
The order of magnitude of the number of theoreticaly different human
being is : 4 ^ (9 x 10^9) let say to simplify 2 ^ (10 ^ 10).
It is very difficult to get a feelling about how big is this number.
It is so big that the number of elementary particules in the universe
2 ^ 270 is riduculously small compare to it.
From: maler@pelvoux.imag.fr (Maler)
Newsgroups: comp.theory
Subject: Re: Accepting sequences?
Date: 8 Oct 92 12:39:09 GMT



frank@Cookie.secapl.com (Frank Adams) writes:

|> In any event, programs which run indefinitely do not generally do *a*
|> computation; instead they act as servers, performing and completing multiple
|> computations.

Not exactly. You can see them as computing continuous function from infinite
sequences to infinite sequences.
-- 
===============================================================
Oded Maler, LGI-IMAG (Campus), B.P. 53x, 38041 Grenoble, France
Phone:  76635846  Fax: 76446675   e-mail: maler@vercors.imag.fr
===============================================================
From: rm@dcs.ed.ac.uk (Robin Milner)
Newsgroups: comp.theory
Subject: COMMUNICATION AND CONCURRENCY, by Robin Milner (Prentice Hall 1989)
Date: 13 Oct 92 14:40:24 GMT
Reply-To: rm@dcs.ed.ac.uk (Robin Milner)
Organization: Laboratory for the Foundations of Computer Science, Edinburgh U


"Communication and Concurrency", by Robin Milner (Prentice Hall 1989)
--------------------------------------------------------------------

Two bits of news which may help people reading my book, and
especially teaching from it:

1  You can get a free copy of SOLUTIONS TO ALL THE EXERCISES
   in booklet form, if you write to  Helen Martin at 
            Prentice Hall International (UK) Ltd,   
            66 Wood Lane End, Hemel Hempstead,
            Hertfordshire HP2 4RG, UK.

2  I have a list of errata for the book, including one non-trivial 
   technical error (about bisimulation "up to").  People rediscover
   this mistake, and write to me about it, at the rate of about once
   every six months!  The list is now available in Latex form by ftp 
   from ftp.dcs.ed.ac.uk ; the file is called export/rm/concerr.tex .  

   If you have any difficulty with ftp'ing the file, please email 
   support@dcs.ed.ac.uk for help.
   
   (Some of the errata --but not most-- were corrected in the second
    printing.)

Robin Milner
From: dubhashi@robin.ag1.mpi-sb.mpg.de (Devdatt Dubhashi)
Newsgroups: comp.theory
Subject: Presburger over the reals
Keywords: Logical theories, decision procedures, real addition
Date: 8 Oct 92 10:26:51 GMT
Organization: Max-Planck-Institut fur Informatik

"Presburger over the reals" is usually called the theory of real addition,
that is, it is the theory of the structure (R,+,<,0). The classical Ferrante-
Rackoff monograph (in the LNM series) gives an Ehrenfeut-Fraisse games based
decision procedure running in double-exponential time and space (the exact
complexity was shown by Berman to be complete for alternating exponential 
time). With restricted quantifiers it is complete for all levels of the 
polynomial time hierarchy (details and references I will need to dig up!).
Of course one can always apply the sledgehammer of Cylindrical Algebraic
Decomposition, but the ferrante-Rackoff method is much more elementary.


Devdatt P. Dubhashi
Max-Planck-Instit\"ut f\"ur Informatik
Saarbrucken, GERMANY


Newsgroups: comp.theory,sci.math
From: sethb@fid.morgan.com (Seth Breidbart)
Subject: Re: Turing's Halting problem revisited
Organization: Morgan Stanley & Co., New York, NY
Date: Tue, 13 Oct 1992 15:59:40 GMT

In article <Bw2D3y.Ltz@dcs.ed.ac.uk> pdc@dcs.ed.ac.uk (Paul Crowley) writes:
>In article <Oct09.020143.90256@yuma.ACNS.ColoState.EDU> ld231782@LANCE.ColoState.Edu (L. Detweiler) writes:
>>H(x,y) surely does not exist, and perhaps neither does H'(x,y).  However,
>>the `halting problem' is so important that an algorithm even for restricted
>>inputs could potentially resolve many currently unsolved problems.  Hence, 
>>let
>>
>>H2(x,y) = 2 if [...]
>>H2(x,y) = 0 if x(y) hangs
>>H2(x,y) = 1 if x(y) halts
>>
>>What is the least restrictive filter [...] such that H2(x,y) exists?
>
>No such least restrictive filter exists.  For any such filter, programs exist
>such that it answers '2'.  Such a filter can be enhanced with a check for
>one or more of these specific tuples of programs and inputs and gives the
>appropriate answer, making it a slightly better answer.

Actually, for any such filter, another filter exists that gives a
correct answer on an infinite number of inputs for which the first
returns 2.  (Exercise: prove this.)

Seth		sethb@fid.morgan.com
Newsgroups: comp.theory
From: mittle@siena.watson.ibm.com (Josh Mittleman)
Subject: Re: Graph-theory question
Date: Tue, 13 Oct 92 19:20:04 GMT
Distribution: usa
Organization: IBM T. J. Watson Research

After a myopic reading of this problem:

>  Given 2 PLANAR graphs G1(e1,v1) and G2(e2,v2), where e1 and e2 are the
>  number of edges and v1 and v2 are the number of vertices (assume e1>e2
>  and v1>v2). What is the complexity of answering the question:
>  Does there exist a copy of G2 in G1?

I wrote:

> This problem is NP-complete.  Let G2 be a k-clique, and you see that your
> problem is identical to the clique problem.

I missed the word "planar", capital letters and all.  Pretty dumb.  Sorry.
However, the problem is still NP-complete.  Let |v1| = n1, and let G2 be a
cycle of length n1.  Then G1 contains a Hamiltonian circuit iff it contains
a copy of G2.  Planar Hamiltonian circuit is itself NP-complete.

===========================================================================
Josh Mittleman (mittle@watson.ibm.com)
J2-C28 T.J. Watson Research Center, PO Box 704, Yorktown Heights, NY  10598
Xref: sparky comp.theory:2182 sci.math:13132 sci.math.symbolic:2705
From: dsims@leo.ece.uc.edu (David Sims)
Newsgroups: comp.theory,sci.math,sci.math.symbolic
Subject: Recurrence relations
Summary: recursive function => closed form expression
Date: 13 Oct 92 21:43:06 GMT
Organization: University of Cincinnati

Does there exist software for finding a closed form expression given a
recursive function?

I would expect such a program to use recurrence relations to solve the
recursive functions.  Any pointers to software packages would be greatly
appreciated.

Thanks in advance.
-- 
David Sims              Dept. of Electrical and Computer Engineering
david.sims@uc.edu       University of Cincinnati
(513) 556-2499          Cincinnati OH  45221-0030
                        USA
From: dan@venus.ics.uci.edu (Dan Hirschberg)
Subject: Re: lower bounds on graph diameter
Newsgroups: comp.theory
Organization: UC Irvine Department of ICS
Date: 9 Oct 92 23:08:57 GMT

In <BvvH0w.A4M@acsu.buffalo.edu> sarnath@acsu.buffalo.edu (Ramnath Sarnath) writes:


>I am looking for references to lower bounds on the diameter
>of graphs, i.e, lower bounds on the longest "shortest path"
>in a graph, when bounds are placed on the degree.


>thanx,

>sarnath

D.S. Hirschberg and C.K. Wong,
"Upper and Lower Bounds for Graph-Diameter Problems
 with Application to Record Allocation"
Jour. Combinatorial Theory, Series B,
Vol. 26, No. 1, Feb. 1979, pp. 66-74.
--
Dan Hirschberg
From: farach@dickens.rutgers.edu (Martin Farach)
Newsgroups: comp.theory
Subject: Re: Graph-theory question
Date: 13 Oct 92 20:44:01 GMT
	<1992Oct13.174344.27225@watson.ibm.com>
Distribution: usa
Organization: /climax/u2/farach/.organization
In-reply-to: mittle@siena.watson.ibm.com's message of 13 Oct 92 17:43:44 GMT

In article <1992Oct13.174344.27225@watson.ibm.com> mittle@siena.watson.ibm.com (Josh Mittleman) writes:

   >  Given 2 PLANAR graphs G1(e1,v1) and G2(e2,v2), where e1
   >  and e2 are the number of edges and v1 and v2 are the 
   >  number of vertices (assume e1>e2 and v1>v2). What is
   >  the complexity of answering the question: 
   >  
   >  Does there exist a copy of G2 in G1?

   This problem is NP-complete.  Let G2 be a k-clique, and you see that your
   problem is identical to the clique problem.

But for k>4, a k-clique isn't planar.  

--
Martin Farach			farach@dimacs.rutgers.edu
Newsgroups: comp.theory
From: thornton@milton.u.washington.edu (Kenneth Thornton)
Subject: Graph-theory question
Organization: University of Washington, Seattle
Distribution: usa
Date: Tue, 13 Oct 1992 16:27:45 GMT


 I have been looking for a text describing the complexity
 of various graph-theory problems, but haven't found one.
 I would appreciate any good references (something for
 graph-theory like Preparata and Shamos is to comp.
 geometry).

 In particular, I would like to know the complexity of
 the following:

 Given 2 PLANAR graphs G1(e1,v1) and G2(e2,v2), where e1
 and e2 are the number of edges and v1 and v2 are the 
 number of vertices (assume e1>e2 and v1>v2). What is
 the complexity of answering the question: 
 
 Does there exist a copy of G2 in G1?
From: rjs@crs.cl.msu.edu (Robert J. Stanton)
Newsgroups: comp.theory
Subject: Need references on quantum error in computer systems
Date: 12 Oct 92 22:51:29 GMT
Organization: Michigan State University

I need some info on quantum error in computer systems.

Anything would be helpful.  I read something about this
long ago and have forgotten my reference.

Thanks.  I will post a summary if I get enough interest.

rjs@crs.cl.msu.edu
rzs@venus.sunquest.com
Newsgroups: comp.theory
From: hiremath@skorpio.usask.ca (Deepta Hiremath)
Subject: 4-colouring problem
Organization: University of Saskatchewan, Saskatoon, Canada
Date: Fri, 16 Oct 1992 18:13:15 GMT

I'm studying the 4-colouring problem (map colouring) and would like
to know the exact NP-Hard algorithm, also if an implementation in C
exists I would request you all to send it to me. No greedy algorithms
or implementations are required.

Thanks,

Deepta Hiremath.
From: burt@aupair.cs.athabascau.ca (Burt Voorhees)
Newsgroups: comp.theory.cell-automata
Subject: Re: what is in CA
Date: 11 Oct 92 06:38:14 GMT

baljeual@uther.calvin.edu (Alan Baljeu) writes:

>I've watched this group for a while now, and I want to know what excactly CA
>entails.  The game of life is discussed regularly.  What other phenomena,
>theoretical constructs belong here?

  A cellular automata (CA) is, formally, a lattice of sites together with
a state space which consists of an assignment to each site of a value
choosen from a finite alphabet (i.e., that's a single state).  There is also
an update rule (a global transition function on the state space) which
determines the value to put at a given site at time t+1 in terms of the
values in some given subset of sites (the neighborhood of the original
site) at time t.  There are generalizations of this but this is basically it.
  CA's are interesting because they give models of systems which generate
rather complex patterns from simple local interaction rules (the update rule)
and it is known that at least some CA's have the capacity to act as
universal computers.
  Reference is Physica D _45_ which devotes the entire issue to CA's
burt voorhees
From: tolman%asylum.cs.utah.edu@cs.utah.edu (Kenneth Tolman)
Subject: Re: what is in CA
Date: 10 Oct 92 18:17:34 MDT
Organization: University of Utah, CompSci Dept

>I've watched this group for a while now, and I want to know what excactly CA
>entails.  The game of life is discussed regularly.  What other phenomena,
>theoretical constructs belong here?

CA stands for Cellular Automata.  I believe the first person to look at them
was Ullman, who showed a checkerboard with stones that underwent rule
determined changes to Von Neumann.  Von Neumann then went and tried to
(succesfully) develop self reproduction with such a system, with an
incredibly large and complex affair.

CA normally entails a finite or infinite grid with transition rules
determining how a cell changes with respect to its neighbors.  Life is
popular because it is simple and is fun, you should definitely play with
life for a few solid days to appreciate its beauty (with a friend).

One area of CA is studying computation within them, because they can be
used to simulate computation and then various properties of CA can be
applied to computation itself!  

Another area of CA is modelling physical systems, which take on a number
of roles.  Reversible CA allow for time reversible evolution, as classical
physics suggests the actual world is.

Currently, most of the work I have personally seen on CA is limited to a few
domains:
  1) Simple local rules for propagation
  2) Studying physics or biology with them

I have seen that some very interesting consequences arise from more complex
rules, such as:
  1) Looking backwards in time some distance to help determine transitions
  2) Using nondeterministic transitions
  3) Having interesting topological spaces which they operate within, to
allow  "FTL" perhaps, or other interesting things.

But the above are not very well studied from what I have seen.

Technically, lots of things are CA-like.  The real physical world appears 
almost to be a CA...  but we don't understand it enough yet.  The game
of "go" is sort of a CA, but has nonlocal propagation.  The field of
"neural networks" is basically CA, normally one or two dimensional with
some sort of integral of "local" cells.

I haven't read every book on CA at this moment, but there appears from
what I have read to be a lot of unexplored territory, very unexplored!
From: am68@unix.brighton.ac.uk (AABStainer? AABSolutely!)
Newsgroups: comp.theory.cell-automata
Subject: Re: general info wanted
Date: 16 Oct 92 12:52:22 GMT
Organization: University of Brighton, UK

I don't know of any programs that run on PC's
but if you look through the old issues of scientific american
in the mathematical recreations (or something) section
many years ago there was an article about J H Conway
which list some very interesting automata and
also an algorithm for the program itself.
try it...the alg is simple!
andy
Newsgroups: comp.theory.cell-automata
From: HANN#m#_RAY@lims-a1.lerc.nasa.GOV (RAY HANN)
Subject: mathematica
Organization: The Internet
Distribution: inet
Date: Thu, 8 Oct 1992 23:37:00 GMT


          hello,
          could anyone tell me if there is a 2-D cellular automata package
          for mathematica?    thanks

Newsgroups: comp.theory.cell-automata
From: rpatil@nmsu.edu (Raj Patil)
Subject: Rules for Cellsim...
Organization: Computing Research Lab
Distribution: comp.theory.cell-automata
Date: Fri, 9 Oct 1992 07:58:29 GMT


Hi:

I am just a begining to learn Cellsim. Has anyone compiled a library
of Rules for Cellsim? (apart from the one it comes with). Anyone willing
to share any Rules.

Regards

raj patil
NMSU-CRL
Las Cruces, NM 88003
From: mburke@yoda.eecs.wsu.edu (Matthew Burke - grad student)
Newsgroups: comp.theory.cell-automata
Subject: Status of Wolfram's 20 questions
Keywords: CA, open questions, Stephen Wolfram
Date: 11 Oct 92 21:24:31 GMT
Organization: Washington State University!



In 1984, "Twenty Problems in the Theory of Cellular Automata" by Wolfram
appeared in the journal, Physica Scripta.

I am interested in whether or not these problems have provided some direction
to the research being done on CA (such as Hilbert's 20 problems did for
mathematics around the turn of the centrury)?

Also, which, if any, of these are no longer open problems?  For example,
I know that work done by Martin, Odlyzko, and Wolfram, and later work
by Guan and He have pretty well nailed down the behavior of additive CA.
Have there been other classes of CA that have been fairly well investigated?


Thanks for the help,

Matt
-- 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%      Matthew M. Burke        mburke@eecs.wsu.edu         %
%   Where am I and what am I doing in this handbasket?     %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Newsgroups: comp.theory.cell-automata
From: stgprao@st.unocal.COM (Richard Ottolini)
Subject: Re: What grad schools study CA?
Organization: Unocal Corporation
Date: Fri, 9 Oct 1992 20:55:41 GMT

In article <1992Oct9.124828.17269@hellgate.utah.edu> tolman%asylum.cs.utah.edu@cs.utah.edu (Kenneth Tolman) writes:
>  What graduate programs in computer science have active research programs
>in CA?  Princeton suggests they do in their literature, but I have seen
>no others..... 


	MIT has profs working on CA in Project MAC (CS), mathematics,
	and geophysics.

I am terrible at remember names, but they have papers in MIT Press books
on CAs
From: baljeual@uther.calvin.edu (Alan Baljeu)
Subject: what is in CA
Organization: Calvin College
Date: Sat, 10 Oct 1992 16:06:48 GMT

I've watched this group for a while now, and I want to know what excactly CA
entails.  The game of life is discussed regularly.  What other phenomena,
theoretical constructs belong here?

Newsgroups: comp.theory.cell-automata
From: MCINTOSH@UNAMVM1.BITNET ("Harold V. McIntosh")
Subject: oops.
X-Unparsable-Date: Wed, 14 Oct 92 00: 51:40 MEX
Organization: The Internet
Distribution: inet
Date: Wed, 14 Oct 1992 06:53:42 GMT

reading the echo of my message, I see that the second
> Jeffrey D. Ullman is a contemporary computer scientist who has collaborated
should have been
> on several compiler books (''dragon books''?). Stanislaw Ulam (see foregoing
Isn't it fun criticizing other people's errors when you make twice as many
of your own in the process?
-
Harold V. McIntosh		|Depto. de Aplicacion de Microcomputadoras
mcintosunamvm1.dgsca.unam.mx	|Inst. de Ciencias, UAP, Apdo. Postal 461
MCINTOSUNAMVM1  (BITNET)	|72000 Puebla, Pue., Mexico