HDTenEightyP/NetNews huggingface dataset:
From: shome@eeserv.ee.umanitoba.ca (Tapas Shome)
Subject: Need reference and guidence to acquire the thought process..Help pl.
Summary: Need to prepare mysself for proving program complexity.
Keywords: Thought process, proving things.
Organization: University of Manitoba, Winnipeg, Canada
Date: Fri, 11 Dec 1992 19:44:09 GMT

 I am a graduate student under going transition from Electrical Engineering to
Computer Engineering. But I think I need a bit of guidance from Pure Math, Abstract Math and Theoretical Computer Science Major.

The problem is two part but the motivation is one

MOTIVATION: I really want to be productive so that I can design proffs
at the level of complexity that is encountered in the Hand book of Theoretical
Computer science and to be able to indentify logical inconsistancies in other peoples proofs. I want to achive these goles in about a years time. I have a back ground of MSC in EE.

PROBLEM:

(i) I can follow the proof ( for example the lower limit proofs of N node d degree graph has routing complexity N**(1/2)/d ). But I am unable to design such a proof
on my own.

(ii) I think, I have a mental blockage when it comes to proof. Also it is quite diffcult for me to follow a brand new proof that is covered in the class in say 50 minutes.

SOLUTION 1:

I have got few books, (i) How to read and do proofs.. Solov
(ii) Problem Solving Through Problems... Larson.

 Could you frankly send me short of what to do every day to aquire the mindset 
needed for the above.
As for myself, I consider, I am above average when it comes to analytical
skills.

All suggestions will be appreciated.


Tapas Shome
shome@eeserv.ee.umanitoba.ca

--
Parallel Systems are easier to built than to use them---- MIT. 
E_mail: (Tapas Shome )shome@eeserv.ee.umanitoba.ca, tshome@ccu.umanitoba.ca
AIM: Ordnung ist das halve Laben. Arbeit macht Ordnung.
Newsgroups: sci.math
From: ross@tarski.tmc.edu (David Ross)
Subject: Re: nonstandard analysis
Organization: University of Hawaii Mathematics Department
Date: Sat, 12 Dec 1992 00:01:50 GMT

In article <1992Dec8.220841.16147@athena.mit.edu> jelliott@athena.mit.edu (Jesse C Elliott) writes:
>The best reference I have seen is by Alain Robert(s?), aptly titled
>_Nonstandard Analysis_.  First he develops nonstandard set theory (or IST)_
>by adjoining three axioms to ZFC which allow one to determine whether


Unfortunately, IST is provably not as powerful as 'full' nonstandard
analysis.  In particular, you cannot do 'nonstandard hull' constructions
in it, and many of the important results ("important"="important to
standard analysis, and without known standard proofs") in the
last decade using n.s.a. have used these hulls.

- David

--
David Ross, Dept. of Math., Univ. of Hawaii at Manoa, Honolulu HI  96822
Internet: ross@math.hawaii.edu  -or- ross@tarski.math.hawaii.edu
Phone: 808-956-9949
Newsgroups: sci.math,sci.math.symbolic
From: siegman@EE.Stanford.EDU (Anthony E. Siegman)
Subject: Re: SIMTEL-20 symbolic mathmatica software
Organization: Stanford University
Date: Wed, 16 Dec 92 20:54:46 GMT

In article <1992Dec16.194957.27147@pony.Ingres.COM> nitin@Ingres.COM
(Nitin Borwankar) writes:    (edited for brevity)

>Given this, There doesn't appear to be a problem with discussing either
>SymbMath or Maple or even letting everyone know of its features when someone
>asks for it.
>
>The fact that there is a *free* version of some such package is definitely
>worth knowing. If the developer is available for comments via the net, all
>the better. This definitely serves research and education.
>
>Speaking for myself, I did find all the above messages valuable.

   Second the motion...

Newsgroups: sci.math
From: solan@smaug.uio.no (Svein Olav G. Nyberg)
Subject: Jesus loves you .... if you Obey
Reply-To: solan@smaug.uio.no (Svein Olav G. Nyberg)
Organization: University of Oslo, Norway
Date: Sat, 12 Dec 1992 10:17:11 GMT

In article <1992Dec11.134959.2607@vax1.mankato.msus.edu>,
vxc15931@vax1.mankato.msus.edu writes:
|> I wonder if Jesus has dealt with quantum mathematics.  I wonder if He
started 
|> it all (together with God).  
|> 
|> If He did, then He sure has a funny way of loving us.

Jesus is a great mathematician. He invented mod2 arithmetic.
Just look:

		3 = 1

|> " Let God and Man decree
|>   Laws for themselves and not for me."
|>                 - A.E. Housman

Wonderful quote. Sounds like my favorite - Stirner.


Solan
(solan@math.uio.no)
Xref: sparky sci.math:17191 rec.puzzles:8057 alt.usage.english:9745
From: iad@cogsci.ed.ac.uk (Ivan A Derzhanski)
Newsgroups: sci.math,rec.puzzles,alt.usage.english
Subject: Re: Naming Large Numbers (Re: Negative Zero)
Date: 18 Dec 92 10:43:32 GMT
Organization: Centre for Cognitive Science, Edinburgh, UK

In article <1992Dec15.210004.2556@hobbes.kzoo.edu> k044477@hobbes.kzoo.edu (Jamie R. McCarthy) writes:
>I submit that one cannot write down, in scientific notation, the number
>x, such that x is the integer component of pi times n, where n is
>sufficiently large.  (Take n to be ten to the power of the number of
>atoms in the universe, for instance.)

Of course one can.

    +-       _   |   |        -+
    |   /|  / \  |   |  _____  |
x = |  / | |   |  \_/ \  | |   |
    |    | |   |         | |   |
    |    |  \_/          | |   |

You tell me what $u$ is, and I'll plug it in.

-- 
 `D'ye mind tellin me whit the two o ye are gaun oan aboot?' (The Glasgow
Ivan A Derzhanski  (iad@cogsci.ed.ac.uk; iad@chaos.cs.brandeis.edu)    Gospel)
* Centre for Cognitive Science,  2 Buccleuch Place,  Edinburgh EH8 9LW,  UK
* Cowan House, Pollock Halls, 18 Holyrood Park Road, Edinburgh EH16 5BD, UK
Xref: sparky sci.math:16967 sci.philosophy.tech:4570
From: bouche2@server.uwindsor.ca (BOUCHER DAVID            )
Newsgroups: sci.math,sci.physics,sci.bio,sci.chem,misc.education
Subject: Re: TIME HAS INERTIA - BASS JEALOUS AND INSECURE-ABIAN VALIDATED
Date: 13 Dec 1992 15:13:37 GMT
Followup-To: sci.math
Organization: University of Windsor, Ontario, Canada

In article <abian.724200923@pv343f.vincent.iastate.edu> abian@iastate.edu (Alexander Abian) writes:
  
>(A2)   TIME HAS INERTIA (i.e. TIME IS MATTER)  AND SOME ENERGY IS 
>       IRRETRIEVABLY DISSIPATEED TO MOVE TIME FORWARD
>
>AND NONE OF THE  existing theories is capable to explain the puzzling
>loss of energy and that (A2) revolutionized both GR and QM.

I have a few questions:

1. "Loss of energy" from what?  I presume that you are referring to something
   other than the limit on the recoverability of energy imposed by the Second
   Law of Thermodynamics?    

2. Since time IS moving forward and has been moving forward since the Big
   Bang, how can there be any "dissipation of energy" to keep it moving?  
   "A body in motion tends to remain in motion unless acted upon by some
   external force"... that is inertia.

3. What is the velocity of time?  Can time accelerate or slow down, and if it
   does, how can we know?

4. In what sense does time move "forward"?  Can time ever move sideways, or 
   backwards?  Does it move in a straight line, or does it have a curved
   trajectory or what?  

5. What experiment(s) do you propose to test your theory?

6. Have you published this theory in any scientific journal subject to peer
   review?  If so, where?  If not, why not?

- db
Newsgroups: sci.math
Subject: Re: Pi Finder
From: a_rubin@dsg4.dse.beckman.com (Arthur Rubin)
Date: 10 Dec 92 00:02:05 GMT
Organization: Beckman Instruments, Inc.

In <1992Dec9.164036.22936@uecok.ecok.edu> patcush@student.ecok.ecu (Cusher Patrick) writes:


>I heard that you could find Pi to a few thousand digits with Mathmatica
>or Maple...How?  I've yet to get it to give me Pi to no more than 3.14159
>and thats it...Any comments?

Mathematica:  N[Pi,3000]
--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
My opinions are my own, and do not represent those of my employer.
My interaction with our news system is unstable; please mail anything important.
Newsgroups: sci.math,sci.philosophy.tech
From: kilston@rddvax.decnet.lockheed.com
Subject: Re: Numbers and sets
Organization: Lockheed Palo Alto Research Labs
Date: Tue, 15 Dec 92 01:31:28 GMT

Please consider an amateur's comments on numbers, drawn from 
practical experience.  For some people, all philosophy should be 
practical (pragmatic), as philosophy is the love of wisdom, and 
wisdom is the practical side of knowledge.  Anyway, here goes:
	1.  Numbers are not simply abstracts:  they arise from the 
interaction of the brain and its environment.  Following Goedel, we 
know arithmetic, like all other thought systems (including logic), 
cannot stand alone.
	2.  Humans (and other animals) first needed ordinals, not 
cardinals:  the pecking order (and the mating order) were more 
important to their social structure than any need to count things.
	3.  How do children learn to count?  They first learn a totally 
arbitrary sequence (an ordinal operation), and only then can they 
perform the one-to-one matching that allows them to assign a 
number in that sequence to the cardinal enumeration of the set being 
counted.  (The ideas of "one", "two", and "many" might indeed arise

independently of a learned sequence.  These are, in fact, the only 
numbers found in certain less numerate cultures.  However, perhaps 
the ideas and language of ordinality are very primitive in those 
societies.  I wonder...)
	4.  Measurements, even those of trained scientists, are in the 
most fundamental sense ordinal.  We never read a scale and know 
that a length or a needle exactly matches a grid marker, only that it 
points near, above, or below it, at least in the analog world we seem 
to inhabit.  An interesting case is given by elevators:  they don't stop

exactly "at" floors (as we sometimes realize to our chagrin), but 
only satisfy the condition of stopping above one switch and below 
another.  Heisenberg's indeterminacy principle, even though it's 
based on the quantum nature of things, might make us think that the 
ultimate calculus of the world is based more firmly on inequalities 
(with order) than on equalities (with perfect "digital" 
correspondence).
	5.  Mathematicians will probably always be revising their 
ideas of what their basic elements mean, as will scientists, and 
after the magnificent contributions of Russell, Whitehead, Goedel, 
and Popper, I would hope we can be a bit tolerant of different 
perspectives as we all play our "Magic Bead Game".

Yours sincerely,
		Steven Kilston    (semi-learned astronomer)
		Lockheed Research Labs
		Palo Alto
		kilston@rddvax.decnet.lockheed.com
Newsgroups: sci.math
From: prener@watson.ibm.com (Dan Prener)
Subject: Re: Names and pictures
Date: Mon, 14 Dec 1992 04:47:41 GMT
Disclaimer: This posting represents the poster's views, not necessarily those of IBM
Organization: IBM T.J. Watson Research Center, Hawthorne, New York

In article <7126@ucsbcsl.ucsb.edu> hubert@ucsb.edu (Hung-Hsien Chang) writes:

> I think it would be nice if the mathematical papers  published on 
> journals contain the pictures of the authors as well. So people 
> will know the authors not just by name.

Why would that be good?  It seems to me that the predominant effect would
be to provide an opportunity for invidiousness.
--
                                   Dan Prener (prener@watson.ibm.com)
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: Re: FEA help!
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Date: Wed, 16 Dec 1992 21:43:20 GMT


In article <1992Dec15.225304.11571@porthos.cc.bellcore.com>, bhatia@bigcat.bellcore.com (Raman Bhatia) writes:
|> In article <1992Dec14.181725@roper.mc.ti.com>, a722756@roper.mc.ti.com (W. Donald Rolph) writes:
|> |> 
|> |> This is by no means a trivial question.  You must first ask the class of FEA to
|> .......
|> |>  
|> |> It is also imperative that you have  a good mesh generator and graphical post
|> |> processor.  The difference between a good mesh generator and an ok mesh generator
|> |> is about 20X in productivity.
|> ........
|> |> 
|> |> A typical system ight cost the following (rough costs):
|> |>   
|> |>      1)  FEA program $5K - $10K year
|> |> 
|> |>      2)  Mesh generator $10K yr
|> |> 
|> |>      3)  Workstation:  $25K
|> |>  
|> |>      4)  color postscript printer $5K to $10K
|> |> 
|> |> This is nearly a 1/3 cost reduction and 10,000 performance improvement over the
|> |> system I put together is 1983!
|> |> 
|> |> 
|> |> -- 
|> |> 
|> |> Regards.
|> |>  
|> |> Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
|> 
|> Thanks for a very informative post. Here's another question. What are
|> the latest in Mesh Generation techniques? 
|> 
|> The last time I dabbed in FEM, the finite-octree (w Delaunay triangulation) 
|> appeared the most promising but there were some concerns about robustness. 
|> I know that companies like PDA engineering (developers of PATRAN) were 
|> looking at "paving". What is the current status of these two techniques, 
|> and are there any new ones out there (AI approaches etc.)?
|> 
|> Raman Bhatia (bhatia@bigcat.bellcore.com)

I have an interesting proof that show that the triangularization schemes all
violate controllability theory at any given point in the model.  The effect is
that in 3D, with typcial dimensions in orthoganoal directions which have
significantly different scales (1.4 in thick by 5 inches wide by 20 inches long),
the triangularizations schemes produce highly unsatisfactory meshes for many
classes of problems, particularly nonlinear problems.  It is interesting to note
the CFd codes are gradually adopting Laplacian mesh generation schemes, schemes
which were popular as early as 1960 for fea.  It should be noted that CFD can be
very suseptible to poor meshes, and perhaps there is a message here!  

I have simplistic proof which suggests that Laplacian mapping produces the
"optimal mesh" fgor certain classes of problems, based on the givven mesh density
provided as input.  I also have s ample program which generates hexahedral meshes
off an arbitray boundary rep trimmed nurb solid model, demonstrating that the
technogy is feasible, and the input is not overly burdensome.
-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
Newsgroups: sci.math.num-analysis
From: bvaddi@eng.auburn.edu (Bala V. Vaddi)
Subject: Re: MINOS
Reply-To: bvaddi@eng.auburn.edu
Organization: Auburn University Engineering
Date: Thu, 17 Dec 1992 05:30:04 GMT


Instead buy GAMS. It comes with MINOS and lots of other packages. Further it is a 4GL language, i.e. easy to use.
Newsgroups: sci.math.num-analysis
From: jpnicol@eng.auburn.edu (Jean-Paul N. Nicol)
Subject: Simultaneous PDE's + ODE's 
Followup-To: sci.math.num-analysis
Reply-To: jpnicol@eng.auburn.edu
Organization: Auburn University Engineering
Date: Wed, 16 Dec 1992 19:44:47 GMT

I am trying to solve a system of simultaneous PDE's and ODE's.  

There are 3 PDE's: standard one dimensional advection-diffusion equations with a nonlinear reaction (uptake) term.  The reaction term couples the PDE's to a system (at each spatial node) of 28 ODE's.  The ODE's come from a biological growth model and are
thus nonlinear and very complicated.

I would welcome any and all suggestions (with references to the literature, if 
available) as to numerical algorithms to solve these equations.

One approach I am considering is to apply a finite difference approximation to the right hand sides of the PDE's, thus converting them to ODE's and solving the
resultant system of 31n (n = # of nodes) ODE's with an adaptive stepsize method
of some sort. Comments?

I have some familiarity with basic numerical methods.  My preference would be to 
use 'canned' FORTRAN numerical routines (ala netlib) to the maximum extent possible.
My hardware choices include PC (486-33), CRAY, SUN (SPARC10), in order of familiarity and ease of use.

Thanks in advance for all the useful help I am sure I will get. Responses can be
posted here or E-mailed directly to me, whichever seems more appropriate.






Newsgroups: sci.math.num-analysis
From: weiping@eng2.eng.monash.edu.au (Weiping Hu Materials)
Subject: Re: FEA help!
Organization: Faculty of Engineering, Monash University 
Date: Tue, 15 Dec 1992 22:55:25 GMT

In article <1992Dec14.212505.27326@cs.wayne.edu> landman@splat.physics.wayne.edu writes:
>From: landman@splat.physics.wayne.edu
>Subject: FEA help!
>Date: Mon, 14 Dec 1992 21:25:05 GMT
>
>Hello Net.People:
>
>
>    I have a question about FEA, specifically software and hardware
>platforms.  A friend is looking into the possibility of purchasing 
>hardware and software to perform FEA calculations for his company.
>I was wondering what software exists (commercial and PD) and what
>platforms are recommended.
>
> Thanks
>
>Joe Landman
>
>Landman@splat.physics.wayne.edu
>landman@hal.physics.wayne.edu
>
There are quite a few commercial FEA packages available, but I've never 
heard of a PD one.  Maybe because of the effort involved to develep any non-
trivial FEA code is too great.  To chose a suitable package, you may need to 
specify the purpose of the analysis.  A package suitable for stress analysis 
may not be suitable for metal forming at all.  There are so-called "general 
packages", such as LUSAS from FEA UK limited.  PAFEC and ABAQUS are other 
examples.

The choice of hardware depends both on the availability of the suitable 
software for that platform and the nature of the analysis.  For elastic 
stress analysis, or heat conduction problems, a 486 PC would generally be 
sufficient, but if it involves large non-linear deformations I would 
recommend more powerful workstations, such as Apollos.

Hope it helps.

Weiping Hu
Newsgroups: sci.math.num-analysis
From: eugene@maui.cs.ucla.edu (Eugene Yuzheng Ding)
Subject:  Source code wanted -- Gaussian elimination
Organization: UCLA, Computer Science Department
Distribution: usa
Date: Wed, 16 Dec 92 22:44:39 GMT


I know this must be a FAQ but I have tried very hard to find the FAQ post
without luck. So --

Anyone has a piece of source code for solving linear equation systems using
Gaussian elimination (in Fortran/Pascal/C/etc.) in hand? Although I can hand
code one out, I don't have instant idea how to make those roundings correct
to avoid error proporgation. 

Any help is appreciated. Helps (and flames :-) please go to my account
eugene@cs.ucla.edu since I'm not a regular reader of this group.

Thanks!!

-- Eugene
Newsgroups: sci.math.num-analysis
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: Re: FEA help!
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Date: Mon, 14 Dec 1992 23:17:25 GMT


This is by no means a trivial question.  You must first ask the class of FEA to
be considered:
 
    1)  rough analysis for simple scaling
    2)  detailed analysis for design verification

The latter is the most typical use of FEA an basically requires a unix type
workstation or above - the memory limitations of dos usually make dos solutions
prohibitive in 3D, which what is generally required for desing verification (our
typical models are on the order of 7000 to 40,000 nodes).

You must also consider whether you plan to do general nonlinear analysis, or only
linear analysis.  A quick review of cpu cycles utilized in a facility suggests
that even if a relatively small number of analyses are nonlinear, then virtaully
all cpu cycles are being used for nonlinear analysis, and you should  design your
facility as a nonlinear facility.

It is also imperative that you have  a good mesh generator and graphical post
processor.  The difference between a good mesh generator and an ok mesh generator
is about 20X in productivity.

Finally you will  need color hardcopy capability in order to distribute your
results.
 
Typical linear codes (all of whcih work at least ok) are:
 
     ANSYS
     NASTRAN

Typical nonlinear codes are:
 
     ABAQUS
     ADINA

You might also look at Marc if it solves special needs of yours.

Commericial pre/post processors include PATRAN (I recommend rev 2.5 for now) and
SUPERTAB from SDRC.

You should also consider one of the many color postscript printers (we have
several from seiko and Tektronix).

Finally you want to get the fastest risc worklstation you can get.  We have
tested the HP9000/730, SGI R4000 based systems, and other of the new 64 bit
floating point chips.  Get yourself 2 1GB dfisc drives if you are doing this for
real.

A typical system ight cost the following (rough costs):
  
     1)  FEA program $5K - $10K year

     2)  Mesh generator $10K yr

     3)  Workstation:  $25K
 
     4)  color postscript printer $5K to $10K

This is nearly a 1/3 cost reduction and 10,000 performance improvement over the
system I put together is 1983!


-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
Newsgroups: sci.math.num-analysis
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: RE: finite element limitations??
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Date: Fri, 11 Dec 1992 23:46:35 GMT


Excellent response - so long as one chooses appropriate shape function (ah now
there's the rub!!) FEA methods dont "fail"!
-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
From: d91dbl@meryl.csd.uu.se (Daniel Blomqvist)
Newsgroups: sci.math.num-analysis
Subject: Curve Fit
Date: 14 Dec 1992 18:38:31 GMT
Organization: Uppsala University
Distribution: world
NNTP-Posting-Host: meryl.csd.uu.se

I'm looking for a program (PD) that can fit a custom function to some data.
No plotting is required, that I can do with Gnuplot.

     Daniel
From: westrich@mira.ncc.umn.edu (Brian Westrich)
Newsgroups: sci.math.num-analysis
Subject: Re: Karmarkar's Algorithm
Date: 12 Dec 92 18:59:47 GMT
Article-I.D.: news2.1992Dec12.185947.8805
Organization: University of Minnesota, Nutrition Coordinating Center

Please repost a summary of the replies you get.  I'm sure many others
would be interested in this.

Thanks.

-- Brian
-- 
Brian Westrich                     | e-mail:  Brian.J.Westrich-1@umn.edu
Nutrition Coordinating Center      | fax:       (612) 627 4191
University of Minnesota (USA)      | phone:     (612) 627 4862
Newsgroups: sci.math.num-analysis,sci.math.stat,sci.math.symbolic