HDTenEightyP/NetNews huggingface dataset:
From: hibrown@sarah.albany.edu (Herb Brown)
Newsgroups: sci.fractals
Subject: Re: fractals/amiga
Date: 13 Oct 92 12:08:31 GMT
Article-I.D.: sarah.1992Oct13.120831.9668
Distribution: sci.fractals
Organization: State University of New York at Albany

In article <PARENIBA.92Oct12192808@dante.nmsu.edu> pareniba@nmsu.edu (Patricia Arenibas) writes:
>I have heard of fractal programs for the IBM, but I was wondering
>if there are any fractal programs for the amiga and where do you
>get them?
>
>thanks
>Patricia

There are many fractal/mandelbrot/julia programs for the Amiga. Most
can be found on Fred Fish disks which are stored on many anonymous ftp
sites. For example, uxi.cso.uiuc.edu (128.174.5.59) is one of the better
sites and usually contains updated FF disks. Look in /amiga/fish/ and
you will find several directories labeled f1  to  f7. Each contains FF
disks.

Here are some excellent prgms to search for.

MandFXP
MandelPAUG
FractalLab
MandAnim
MandelMountains
IceFrac
MandelMania
FracGen
TurboGen
CPM-Mandelbrot
MAK
MandelSquare


I'm certain I have left out several, but I hope this is a good start.

Herb


-- 
Herb Brown  Math Dept  The Univ at Albany  Albany, NY 12222  (518) 442-4640
Director,                                          hibrown@math.albany.edu  
Computer Assisted Instruction in Mathematics       hibrown@csc.albany.edu
--------------------------------------------------------------------------
From: akumar@ese.ese.ogi.edu (Alok Kumar)
Newsgroups: sci.fractals
Subject: Fractal Heterogeneity
Keywords: heterogeneity
Date: 9 Oct 92 20:41:51 GMT
Article-I.D.: ogicse.43890
Distribution: world
Organization: Oregon Graduate Institute - Department of Env. Science and Eng.

i am presently doing research in the field of trying to understand 
the movement of contaminants below the surface of the earth. the 
inherent problem in this field is trying to characterize the
heterogeneous nature of the subsurface of the earth. it seems some
work has been done in trying to characterize such properties in other 
fields.
i would appreciate if anyone could send me informations regarding 
work done in this field or any related field. the key is trying to 
understand the variability in properties at a large scale that 
could be self similar in nature.

thank you
alok kumar
 
Newsgroups: sci.fractals
From: pooler@vccnorthe.its.rpi.edu (Robert Peter Poole)
Subject: Re: other iterations
Organization: Rensselaer Polytechnic Institute, Troy, NY
Date: Fri, 16 Oct 1992 19:47:36 GMT


Well, I attended a lecture once on fractal generation... it was quite
fascinating.  Here are some variants on the mandelbrot set:

z = z^n + c

In this case, n determines the number of major "lobes" that the Mandelbrot-like
set contains.  For n = 2, you get a normal M-set, with a "butt" (2 lobes).
You can also use fractional numbers for n instead of integers.  I've been told
n = 1/2 is rather boring to look at, and n = 1 is not a good idea either, but
n = pi might be interesting, or n = 1/e.

z = sin(z) + c
z = cos(z) + c
z = tan(z) + c
etc.

These all give fascinating repeating structures that have a Mandelbrot/Julia
set "feel" to them.  I can't really describe them too well, except to say
that the structures tend to repeat linearly in the direction of the real
axis (as you would expect from trig functions).

Equations for complex-number equivalents of the real-number trig functions are,
of course, available in the CRC math reference, but you can rederive them
from the exponential equation quite easily.

I am not sure how "pretty" or "interesting" the hyperbolic functions would be.

Rob Poole
pooler@rpi.edu
pooler@cs.rpi.edu
Newsgroups: sci.fractals
From: Chris.Jeris@bbs.oit.unc.edu (Chris Jeris)
Subject: Re: Mandelbrot Set
Organization: Extended Bulletin Board Service
Date: Fri, 16 Oct 1992 23:04:28 GMT

The M-set doesn't really contain every Julia set; rather it acts as a 'map'
of all the quadratic Julia sets in this sense:

Refer to by J[c] the Julia set constructed in this manner:
For each point z in the complex plane, calculate the iterations
		z[n+1] = z[n] ^ 2 + c
A point is in the Julia set if z[n] fails to escape to infinity.
(In practice, the Julia is usually computed by seeing if |z[n]| exceeds
some preset threshold value, commonly 2, after a specified number of iterations
n.)  Well, when plotted on the complex plane, some of the Julia sets are
connected and some of them are not.

The Mandelbrot set is constructed similarly--EXCEPT for a few changes in the
meaning of the variables.  To construct M, for each point c (NOT z) in the
complex plane, starting with z[0] = 0, iterate
		z[n+1] = z[n] ^ 2 + c
and a point is in the Mandelbrot set if z[n] fails to escape to infinity.

It turns out that J[c] is connected if and only if c is a member of M.
I don't really understand the math used to prove it, I just like to play
with Fractint :)	Hope this helps.

Chris Jeris	cjeris@imsasun.imsa.edu	The Illinois Math & Science Academy
--
   The opinions expressed are not necessarily those of the University of
     North Carolina at Chapel Hill, the Campus Office for Information
        Technology, or the Experimental Bulletin Board Service.
           internet:  bbs.oit.unc.edu or 152.2.22.80
From: kaufman@eecs.nwu.edu (Michael L. Kaufman)
Newsgroups: sci.fractals
Subject: Re: FDESIGN question
Keywords: fractals
Date: 9 Oct 92 14:48:45 GMT
Organization: EECS Department, Northwestern University

In article <AA2I2rgWBA@inkomi.riga.lv> uldis@inkomi.riga.lv writes:
>Where I can get fractal generating programmcalled FDESIGN ?  

It and it's sources are on wsmr-simtel20.army.mil in <msdos.fractal>.

Michael


-- 
Michael Kaufman | I've seen things you people wouldn't believe. Attack ships on
 kaufman        | fire off the shoulder of Orion. I watched C-beams glitter in
  @eecs.nwu.edu | the dark near the Tannhauser gate. All those moments will be
                | lost in time - like tears in rain. Time to die.     Roy Batty
From: hart@wazoo.eecs.wsu.edu (John C. Hart)
Newsgroups: sci.fractals
Subject: Re: Lebesgue measure in Fractal Dimension
Date: 7 Oct 92 15:55:35 GMT
Article-I.D.: serval.1992Oct7.155535.10513
Distribution: usa
Organization: Washington State University

In article <ggrzgca@rpi.edu> sassoj@rs6412.ecs.rpi.edu (John J. Sasso Jr.) writes:
>   Now, the Cantor set has Lebesgue measure 0 for the Lebesgue measure defined
>in spaces R^1, R^2, etc...  However, the Cantor does have a fractal dimension
>(or Hausdorff dimension) between 0 and 1 (I cannnot recall the value), and
> log(2)/log(3)

>I'll call this dimension Df.  Is it possible to define a Lebesgue measure in
>a space of dimension Df (R^Df) such that the measure of the Cantor set is a 
>value other than 0?

It sounds like you're looking for Hausdorff measure. See either of Falconer's books:
The Geometry of Fractal Sets, Cambridge University Press, 1985; or
Fractal Geometry, Wiley, 1990.

-John Hart
 School of EECS
 Washington State University
 Pullman, WA 99164-2752
From: scavo@cie.uoregon.edu (Tom Scavo)
Newsgroups: sci.fractals
Subject: Re: Mandelbrot Set
Date: 14 Oct 92 21:54:56 GMT
Article-I.D.: nntp.1992Oct14.215456.24685
Organization: University of Oregon Campus Information Exchange

In article <5f1zj-c@rpi.edu> fokp@rpi.edu writes:
>The equation is:
>Zn+1=Z^2+C   where
>C is a complex number namely x+yi.
>The idea is to make a grid on the computer screen with the boundary
>of -2 to 2 for the x axis and -2 to 2 for the y axis.  Then you start
>calculating the set by putting every coordinate in the constant C and 
>Z.  You use the point as an initial value as well as a constant.

When calculating the Mandelbrot set, compute the orbit of  0  (the
critical point) for each value of  c .  Also, the  M  set lives in
parameter space with  Re(c)  along the horizontal axis and  Im(c) 
along the vertical axis.  The Julia set, on the other hand, is in
the complex plane with  Re(z)  and  Im(z)  along the horizontal
and vertical axes, respectively.  The parameter  c  is fixed in 
the case of Julia set.

>It is very similar to the Julia Set. In fact, Mandelbrot claimed that
>the Mandelbrot Set have contain every Julia Set.  

For certain values of  c , called _Misiurewicz points_, there is a
structural relationship between the  M  set and the corresponding
Julia set.  See Experiment 17.7 in Devaney's _A First Course in
Chaotic Dynamical Systems_ (Addison-Wesley, 1992) or section 7 in
Bodil Branner's excellent paper in _Chaos and Fractals:  The Math-
ematics Behind the Computer Graphics_ (AMS, 1989).  I believe the
definitive work on this was done by Tan Lei, but I don't have a
reference.

-- 
Tom Scavo
scavo@cie.uoregon.edu
From: N020BA@tamvm1.tamu.edu
Newsgroups: sci.fractals
Subject: Re: Chaos, fractals and society
Date: 17 Oct 92 01:17:54 GMT
Organization: Texas A&M University

In article <#j3zr0@rpi.edu>
fokp@bray1b.its.rpi.edu (Pingtao (Ben) Fok) writes:
>
>I am doing a journal on Chaos, fractals and society.
 
   By "doing a journal", do you mean writing a paper, thesis or diss-
ertation on the subject or are starting a publication that one submits
articles to?
 
>I am trying to understand the relation between those the subject above.
 
  Could you be more specfic as to what you want? Are you interested in us-
ing fractals and chaos to model social dynamics? Are you talking about the
sociology of the theories? Inquiring minds want to know!
 
 
========================================================================
"You speak evil of that which is fair    | My opinions are mine and mine
beyond the reach of your thought and on- | alone. I speak for myself and
ly little wit can excuse you."-J.R.R.    | no-one else.
Tolkien in Lord of the Rings trilogy.    |______________________________
Reply to N020BA@tamvm1.tamu.edu.                 Love is an IFS!
From: brownt1@lincoln.ac.nz
Newsgroups: sci.fractals
Subject: Re: fractals/amiga
Date: 15 Oct 92 08:56:30 NZDT
Distribution: sci.fractals

In article <PARENIBA.92Oct12192808@dante.nmsu.edu>, pareniba@nmsu.edu (Patricia Arenibas) writes:
> I have heard of fractal programs for the IBM, but I was wondering
> if there are any fractal programs for the amiga and where do you
> get them?

As well as the list of fractal programs someone else posted, there's 
FracBlank, a fractal screen blanker that  displays "Real plane" and 
"Cosmic flame" fractals.  The only drawback is that often the images 
created are to interesting to disrupt by touching a key....

Cheers -tb
----------------------------------------------------------------------
     Terry Brown, INTERNET brownt1@lincoln.ac.nz, 
                  UUCP     tb@tbnode.equinox.gen.nz,
                  /earth is 98% full ... please delete anyone you can.


Newsgroups: sci.fractals
From: lmitchel@nyx.cs.du.edu (lloyd mitchell)
Subject: Re: fractal audio?
Organization: University of Denver, Dept. of Math & Comp. Sci.
Date: Sun, 11 Oct 92 02:28:28 GMT

In article <1992Oct11.022222.17937@mnemosyne.cs.du.edu> habrams@nyx.cs.du.edu (Howard Abrams) writes:
>  Does anyone have/know-of any information on fractial compression
>of audio?
>

The time signature of an audio track would probably resemble a turbulent
time history, at least in the lower frequencies.  Some work was done in fractal
compression of turbulence data, using a variation of the collage theorem.  If
there is interest, I can attempt to find the reference.  (It's probably on my
desk, in which case it's lost forever.  :-)

Kerry Mitchell
Newsgroups: sci.fractals
From: pareniba@nmsu.edu (Patricia Arenibas)
Subject: fractals/amiga
Organization: NMSU Computer Science
Distribution: sci.fractals
Date: Tue, 13 Oct 1992 02:28:08 GMT

I have heard of fractal programs for the IBM, but I was wondering
if there are any fractal programs for the amiga and where do you
get them?

thanks
Patricia
Newsgroups: sci.fractals
From: amalver@eniac.cs.oberlin.edu (Aaron Malver)
Subject: Re: Mandelbrot Set
Organization: Oberlin College Computer Science
	<5f1zj-c@rpi.edu> <1992Oct14.145617.18124@uwasa.fi>
Date: Wed, 14 Oct 1992 21:17:11 GMT
X-Posted-From: eniac.cs.oberlin.edu
NNTP-Posting-Host: sol.ctr.columbia.edu

I hope that I'm answering the right question here.

The Mandelbrot set is generated by iterating the equation
Zn+1=Z^2+C for various values of Z.  This was already posted.

Julia sets are generated (at least those associated with the
Mandelbrot set) by fixing Z and allowing C to vary.  There are
some very beautiful Julia sets associated with functions other
that the one above, as well as different "Mandelbrot sets".

There are whole books devoted to the relationships between the
Mandelbrot set and Julia sets.  The mathematics can be quite deep and
very beautiful.  I would recommend any book written by Prof. Devaney
from Boston U.

Aaron Malver
amalver@cs.oberlin.edu
--
Aaron Malver
(amalver@occs.cs.oberlin.edu)
if you can read this, you're too close.
From: kmc@netcom.com (Kevin McCarty)
Newsgroups: sci.fractals
Subject: Re: Aperiodicity in the Lorenz Attractor
Date: 7 Oct 92 05:03:16 GMT
Organization: Self

In article <10642749.4.718355983@eng2.eng.monash.edu.au> 10642749@eng2.eng.monash.edu.au (MARTIN OLBRICH) writes:
>  Greetings!
>  I am currently completing an undergrad prac on the lorenz attractor, and 
>I'm having some trouble with the aperiodicity of the attractor. Having spent 
>some time looking at lots of pretty pictures, I can accept with no worries 
>the idea that the whole structure forms an infinite layering effect, and 
>therefore the attractor can easily be aperiodic.
>
>  The problem is how to say this in a report. Is there any proof that the 
>attractor is aperiodic?? 

Along this line, there just appeared in the latest (Oct. 1992) issue
of Bulletin of the American Mathematical Society, 27:2, pp. 298-303

Hastings, S. P., and Troy, W. C. "A Shooting Approach to the Lorenz Equations"

    Abstract.  We announce the outline of a proof of the existence of a
    homoclinic orbit of the Lorenz equations.  In addition, we develop a
    shooting technique and two key conditions, which lead to the existence
    of a one-to-one correspondence between a set of solutions and the set
    of all infinite sequences of 1's and 3's.


-- 
Kevin McCarty (kmc@netcom.com)
From: jesjones@milton.u.washington.edu (Jesse Jones)
Newsgroups: sci.fractals
Subject: Re: 3D fractals
Keywords: fractals, chaos, Mandelbrot
Date: 17 Oct 92 00:46:30 GMT
Article-I.D.: u.1992Oct17.004630.12310
Organization: University of Washington, Seattle

In article <1992Oct16.173639.166789@watson.ibm.com> gaitat@gaitat.kgn.ibm.com (Saki) writes:
>I am looking for some information for generating 3D fractals
>The FAQ wasnt very useful.

   Just what are we talking about here? True 3D fractals? The Mandelbrot Set
rendered in three dimensions? If all you want is to render fractals in 3D
I can give you some references.

  --Jesse
From: israel@unixg.ubc.ca (Robert B. Israel)
Newsgroups: sci.fractals
Subject: Re: Strange attractor questions
Date: 16 Oct 1992 18:27:25 GMT
Organization: University of British Columbia, Vancouver, B.C., Canada
NNTP-Posting-Host: unixg.ubc.ca

In article <00962123.79FB9060@128.104.39.173> sprott@128.104.39.173 writes:
>3) Is there a mapping or system of ODE's involving only polynomials whose
>solution attracts to:
>     a) a 2-torus

It's easy in 4 dimensions, e.g. the ODE system
     x' = y + x (1 - x^2 - y^2)
     y' = -x + y (1 - x^2 - y^2)
     z' = a w + z (1 - z^2 - w^2)
     w' = - a z + w (1 - z^2 - w^2)
where a is a positive irrational constant.  The attractor is the surface
x^2 + y^2 = 1, w^2 + z^2 = 1.

A bit more complicated to make a 3-dimensional example.  Try the
following ODE system:

   x' = x (- c z + p - p^3 - p z^2) + a y
   y' = y (- c z + p - p^3 - p z^2) - a x
   z' = 2 (p + b) (c p + z - p^2 z - z^3)

where p = x^2 + y^2 - b, a, b, c are constants, and b > 1.  Except for
values of the constants that create periodic orbits, the attractor is
the 2-torus  p^2 + z^2 = 1.  

>     b) a 3-torus

Easy in 6 dimensions, analogous to my first example.
-- 
Robert Israel                            israel@math.ubc.ca
Department of Mathematics             or israel@unixg.ubc.ca
University of British Columbia
Vancouver, BC, Canada V6T 1Y4
Newsgroups: sci.materials
From: 03249587@mama.minmet.uq.oz (Darcy Clark)
Subject: Polymer Microscopy
Organization: Prentice Centre, University of Queensland
Date: Fri, 9 Oct 1992 06:21:36 GMT

 I'm doing some research in the polymers field and at the moment doing some
 high-resolution TEM (+ some SEM) - I'd like to here from anyone who is conducting research in of a similar vein!
				  Darcy Clark
				  Uni of Queensland,Brisbane,Austrlia
				  email: 03249587@minmet.uq.o.zua
				  ***ignore above email address**
				  email: 03249587@minmet.uq.oz.au
From: cjs1722@zeus.tamu.edu (STEPANIAN, CHRISTOPHER JOHN)
Newsgroups: sci.materials
Subject: Solicitations on usenet
Date: 9 Oct 92 15:44:00 GMT
Article-I.D.: zeus.9OCT199210441915
Organization: Texas A&M University, Academic Computing Services
News-Software: VAX/VMS VNEWS 1.41

Could someone please inform me of the policy (legal,ethical, or otherwise) for
solicitations on usenet?

Must they be posted for a group designated for solicitations?

Thanks in advance,

Chris Stepanian
Dept Ocean Engineering
Texas A&M  
Newsgroups: sci.materials
From: ps02@ns1.cc.lehigh.edu (PENELOPE E. SMITH)
Newsgroups: sci.materials
Subject: Re: Uses of Be
Date: 7 Oct 92 22:22:41 GMT
Organization: Lehigh University

In article <1992Oct2.113921.2739@mtroyal.ab.ca>, dhayward@mtroyal.ab.ca writes:
>For years I have been interested in the present and future uses of
>Berrylium. Due to it's many spectacular properties it should be more
>common than it is. any info?
>
Beryllium oxide is used as the electrical insulator and thermal conductor
between electrified electronic devices generating heat and their heat sinks.
If you look in the right trade mags, for example Microwaves&RF (maybe
Photonics Spectra) you can find mention of these things.
    (from my husband, Eric Christenson, an Engineer)

    
-- 
 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Penelope E. Smith               PS02@NS.CC.LEHIGH.EDU
Department of Mathematics       PS02@LEHIGH.BITNET
Lehigh University
Bethlehem, PA
Newsgroups: sci.materials
From: lachlan@dmp.csiro.au (Lachlan Cranswick)
Subject: Re: Uses of Be
Organization: CSIRO Division of Mineral Products, Melbourne, AUSTRALIA
Date: Sat, 10 Oct 1992 13:08:49 GMT

ps02@ns1.cc.lehigh.edu (PENELOPE E. SMITH) writes:

>In article <1992Oct2.113921.2739@mtroyal.ab.ca>, dhayward@mtroyal.ab.ca writes:
>>For years I have been interested in the present and future uses of
>>Berrylium. Due to it's many spectacular properties it should be more
>>common than it is. any info?
>>
>Beryllium oxide is used as the electrical insulator and thermal conductor
>between electrified electronic devices generating heat and their heat sinks.
>If you look in the right trade mags, for example Microwaves&RF (maybe
>Photonics Spectra) you can find mention of these things.
>    (from my husband, Eric Christenson, an Engineer)

I would not be surprised if it never becomes common in products
as it is highly toxic.  I come across beryllium windows in X-ray Tubes for
Powder X-ray Diffractometers.  It is really nasty, not only because
of its toxicity but it is very fragile.  If broken, splinters 
fly everywhere.  Philips, the maker of the X-ray tubes, provide
a free disposal service for used X-ray tubes because berylium is
so toxic.

A recent local TV news item on health risks for artist
mentioned Berylium as giving skin tumours on fingers because of
berylium salts.

Merck goes into more detail:-

"Death may result from short exposure to incredibly low concentrations.
Acute: pneumontis may result from single exposure to berylium
and accasionally is fatal.  Chronic: pulmonary granulomatous
disease may appear in 3 months  to 6 years, often after short
exposure to low concentrations.  Uncertainty as to complete
recovery.  Death rate about 25%.  Rewiew: "Berylium
and Berylliosis" by J. Schubert in Sci. American 199,
no 2, pp 27-33 (Aug. 1958)"
-- 
  Lachlan Cranswick  -  CSIRO             _--_|\  lachlan@dmp.CSIRO.AU
  Division of Mineral Products           /      \ tel +61 3 647 0367
  PO Box 124, Port Melbourne 3207        \_.--._/ fax +61 3 646 3223
  AUSTRALIA                                            v 
Newsgroups: sci.materials,sci.chem,sci.physics
From: gawne@stsci.edu
Subject: IR detector discussion ???
Organization: Space Telescope Science Institute
Distribution: na
Date: Thu, 8 Oct 1992 19:58:03 GMT

From Bill Gawne at the Space Telescope Science Institute
gawne@stsci.edu

Hi all.  Is there anyone out there in netland interested in
discussing IR detector materials?  I was thinking of InSb
Pt:Si, and HgCdTe in particular; but any lead chalcogenide
folks would be welcome too.

I'm interested in fundamental physics, crystallography,
and chemistry of the materials.  Also engineering involved
in producing detector arrays for both astronomical and
terrestrial applications.

Please e-mail or post replies to sci.materials.  Thanks,

-Bill
From: WEBER@JEDI.SSD.LMSC.LOCKHEED.COM (Kevin Weber)
Subject: Re: Uses of Be
Followup-To: sci.materials
Organization: 78-30
Date: Mon, 12 Oct 92 13:53:50 GMT



> "Death may result from short exposure to incredibly low concentrations.
> Acute: pneumontis may result from single exposure to berylium
> and accasionally is fatal.  Chronic: pulmonary granulomatous
> disease may appear in 3 months  to 6 years, often after short
> exposure to low concentrations.  Uncertainty as to complete
> recovery.  Death rate about 25%.  Rewiew: "Berylium
> and Berylliosis" by J. Schubert in Sci. American 199,
> no 2, pp 27-33 (Aug. 1958)"
> -- 
Look at the date of that article! No one has died of berylliosis in 30
YEARS!!! 
There have been 2 (yes, count them, 2) cases of berylliosis in the last 20
years. The toxicity of beryllium is ONLY related to powder form. Contact in
any other pure form is absolutely harmless. Back in the 50's when beryllium
was becoming popular, some workers contracted berylliosis.  Only a small
fraction of people, about 3%, can even get berylliosis at any exposure
level.  Most of us are totally immune to berylliosis.  There was an
immediate panic, evidenced by your quote. Research quickly determined that
dry machining and ore crushing operations caused the dust which caused
berylliosis.

Here at Lockheed we constantly use beryllium, it has many properties
unmatched by any other material known to man, and it is extremely harmless
when proper precautions are followed.

You could propably find a 50's article which shows the benefit of cigarette
smoking.  I suggest to look into more recent work in the area.

kevin weber
Newsgroups: sci.materials
From: kester@mte.ncsu.edu (Dan Kester)
Subject: Re: Uses of Be
Organization: North Carolina State University
Date: Fri, 16 Oct 1992 13:44:41 GMT


>In article <1992Oct2.113921.2739@mtroyal.ab.ca>, dhayward@mtroyal.ab.ca
writes:
>>For years I have been interested in the present and future uses of
>>Berrylium....
>


I use Be as a substrate for thin films when I want to do RBS analysis
(Rutherford backscattering) of the films.  RBS works best when the substrate
material has a lower atomic number than the material you're analyzing.  I work
with BN films and the only good substrate with a smaller Z is Be.

Dan Kester
kester@mte.ncsu.edu