HDTenEightyP/NetNews huggingface dataset:
From: mike%jim.uucp@wupost.wustl.edu (Mike Suter)
Subject: Re: Material Science for my Windshield
Keywords: broken windshield glass
Organization: BITS, St. Louis, MO
Distribution: na
Date: Fri, 10 Apr 1992 21:57:38 GMT

hkon@athena.mit.edu (Henry Kon) writes:

>ANY HELP SOUGHT !!!!
>I have a hairline fracture in my windshield.  It is small, but growing. 
>Someone told me that they heard of putting some kind of glue a the growth
>end.  I don't kow what kind of glue to use !!

Check w/ your insurance co--some of them pay the full cost (no
deductable) to have it repaired, to prevent you from waiting until
it spreads and then have the insurance co pay to have it replaced.
Of course, this assumes you have comprehensive coverage.

mike%jim.uucp@wupost.wustl.edu
From: tk@ai.mit.edu (Tom Knight)
Newsgroups: sci.materials
Subject: Re: Dopant delineation in silicon
Date: 11 Apr 92 14:46:57 GMT
Distribution: sci.materials
Organization: MIT Artificial Intelligence Lab
In-reply-to: mikael@inmic.se's message of 10 Apr 92 09:22:24 GMT

In article <1992Apr10.092224.20684@sics.se> mikael@inmic.se (Mikael Jargelius) writes:

   In order to obtain contrast between layers I use different wet chemical
   etchants, e.g. diluted HF for aluminium, buffered HF for silicon dioxide etc.

   Now, I would like to know if there are any good suggestions for methods to use
   to obtain delineation of doped regions in silicon. I have used Sponheimer-
   Mills and Rowe etchants and got useful results for high dopant concentrations,
   but I would also like to detect lower dopant levels in a reproducible way.

   Perhaps some kind of plating could do the job?

You might check out the (probably out of print) book "Semiconductor
Measurements and Instrumentation", by WR Runyan, McGraw-Hill '75.  It
has a discussion on visualization stains.  I believe their suggestions
included adding very small amounts of cupric nitrate to the buffered HF
to decorate the diffused regions.

If anyone knows effective techniques for removing metal-2 without
removing metal-1, I'd be grateful for some hints.

From: glenr@hpdmd48.boi.hp.com (Glen Ray)
Date: Wed, 8 Apr 1992 22:23:05 GMT
Subject: Re: Can of Worms (please open here)
Organization: Hewlett Packard - Boise, ID
Newsgroups: sci.materials

   I may be speaking out of place, in that
I am not now nor have I been to college.
However I am an industrial craftsman and 
have been working in industry for 19 years.
   My comment comes in thye form of a question.
If the industrial leaders of tomorrow don't
understand metals and how they work, How are
they and industry going to utilize metal as
basic building/manufacturing materials ?
   Plastics have not replaced metals in industry
yet. Until they do, Don't stop teaching metalurgy
            Just my opinion
                Glen Ray




As previously stated "Just my opinion" not
          Hewlett Packard's
Newsgroups: sci.materials
From: tyadav@athena.mit.edu (Tapesh Yadav)
Subject: Re: Why do Fullerenes form in MBE?
Organization: Massachusetts Institute of Technology
Date: Thu, 9 Apr 1992 23:41:47 GMT

=================
In article <phrjz0#@lynx.unm.edu> swami@chtm.eece.unm.edu (Swami srinivasan) writes:
>
>	have a nagging question...
>
>	He mentioned that fullerenes can also be made by MBE growth.
>

  MBE process is news to me. Did you ask him for references?

>	How does a fullerene form? i would have expected a flat
>thin film of C to deposit. What makes the few atoms that first contact
>the substrate to grow upward, with the "prior" knowledge of  C-60
>geometry? How does the structure actually grow and under what special
>conditions (in an MBE)? Can these be grown with MOCVD?
>

 Fullerenes do grow, quite profusely and in concentric helical pattern,
 on negative electrodes in electrode arc process. These fullerenes are
 being called bucky tubes - for their tubular shapes.
 Reference: S. Iijima, Nature, last year.
 
 I am not aware of C60 growing upward. C60 closes. C60, therefore has
 to begin, grow/extend and then end. 

 Fullerenes are convex structures and follow Euler's theorem of geometry.
 They have to have 12 pentagons. Bucky  tubes have all these pentagons at
 the tube ends. The growth of the bucky tubes therefore begins with pentagons.
 Pentagons lead to curvature. This curvature gives the first direction -
 "growth upward." 

 The helical structure of the each bucky tube easily and elegantly permits
 self growth with prior knowledge - much like the DNA in life forms. Use some
 jelly beans/potato pieces with match sticks/tooth pick and play it out. 
 See Iijima's bucky tube figures in Nature and in Science (last 
 year sometime), to get hints.


>	More generally, how do fullerenes form at all? There must be
>	I hope these aren't silly questions. Any info/references will
>be welcome. i am curious about the topic and slowly getting interested,
>anticipating some non-linear optics applications. 
>
>							swami srinivasan

 Formation mechanism: different processes seem to suggest
 different hypothesis. For the graphite vaporisation processes: the 
 hypothesis that is still not disproved is by
 Smalley et al. (See latest issue of Accounts of Chemical Research - special
 issue on buckministerfullerenes). 

 Your anticipation on nonlinear optics applications is already racing towards
 reality. See recent issues of Nature (Mar or Feb). So don't get interested
 slowly. Plunge. There is too much fun in the global bucky olympics.

T.Y.
----
tyadav@athena.mit.edu
From: tmiyazak@etl.go.jp (Takehide Miyazaki)
Newsgroups: sci.materials
Subject: Need info on IUPAP Conf.
Date: 7 Apr 92 11:03:45 GMT
Organization: Electrotechnical Laboratory, Tsukuba Science City


     Hi!

     Does anybody know ANY information on " 6-th International
Symposium on Small Particles and Inorganic Clusters ", which will
be held in Chicago, Sept. 16-22, 1992 ? 

Especially I would like to know session topics, dead line for papers and
important addresses. 

     Thanks a lot in advance.

     Takehide Miyazaki , Electrotechnical Laboratory
     e-mail: tmiyazak@etl.go.jp
Newsgroups: sci.materials
From: akarpowicz@mta.ca (Adam Karpowicz)
Subject: Re: carbon fibre bows
Reply-To: akarpowicz@mta.ca
Organization: Mount Allison U, Sackville, N.B. Canada 
Date: Mon, 13 Apr 1992 00:40:26 GMT


I want to thank everyone who responded to my questions on
carbon/graphite composites, the discussion that followed was
enlightening.

I still do not know what is carbon foam.    

Adam
Newsgroups: sci.materials
Date: Wed, 15 Apr 92 15:27:57 MDT
From: haibo@bones.caedm.byu.edu (haibo yu)
Subject: LeMont D-10 Image Analyzer
Lines: 8
Distribution: world
Organization: Brigham Young University, Provo UT USA

Hello

Anyone knows how can I get info about LeMont D-10 Image Analyzer?  I need
the vendor's phone and address.

Thanks in advance.

Haibo Yu
Newsgroups: sci.materials
From: chenina@rhrk.uni-kl.de (Robert Chenina [Chemie])
Subject: Fused Silica and Fluorescence
Organization: University of Kaiserslautern, Germany
Date: Mon, 6 Apr 1992 06:34:41 GMT



	Hello World,

	I'm looking for every kind of information obout the fluorescence
behaviour of high grade fused silica fiber optic bundles or more generally
speaking of fused silica.
	Any help will be appreciated.
		Robert
  ****************************************************************************
  * Robert Chenina, Dpt. of Physical Chemistry, University of Kaiserslautern *
  *          Erwin-Schroedinger-Str, D-6750 Kaiserslautern, Germany          *
  *             Phone: + 49 631 205 2534, Fax: + 49 631 205 3200             *
  *                       Email: chenina@rhrk.uni-kl.de                      *
  ****************************************************************************
Newsgroups: sci.materials
From: routd@woods.ulowell.edu
Subject: call for a news group on LIQUID CRYSTAL TECHNOLOGY.
Organization: University of Lowell
Date: Fri, 17 Apr 1992 17:36:11 GMT


CALL FOR A SCI. GROUP ON LIQUID CRYSTAL TECHNOLOGY.
--------------------------------------------------

Dear netters,

	Liquid Crystals are becoming a major part of our daily lives. Your
watch may have a LCD. Your Car might be having a couple of them! Are not 
they look sleek! If you are not a worker in this area, you might not have
a chance to look at them more closely. If you see Liquid crystals under a 
polarizing microscope, you probably would think,"I have never seen more beautiful
things in life!"
	Liquid crystals, though discovered by a botanist a century ago, only 
became very active by the 1950-60s.This field underwent a sea change in the
later half of this century! First fabrication of LCDs were around 1960-70. 
Discovery of Ferroelectrics, Polymeric Liquid crystals, attracted a lot of
attention to this feild!

	It becomes a meeting ground of so many Physical, chemical and biological
phenomena now. To name a few, There has been similarity in High Tc superconducti
vity and Twist grain boundary phase of smectic phase. Formation of galaxies can be
be understood from temporal observation of liquid crystal defects. etc. DNA
is found to have LC phases!The list is endless...................

	The purpose of this group would be to discuss and solve problems relating
to liquid crystals, new developments, new products, crazy but true ideas etc....

	I have already posted similar requests in the SCI.engr. and SCI.physics
news groups. The response so far has been good, though not terrific. Expectinng
a few more votes and suggestions in this regard.

	Thanx in advance.

	Deeleep K. Rout
==================================================================================
Dept. of Chemistry
U Mass. Lowell
MA 01854

(508)-934-3712 (Lab.)
routd@woods.ulowell.edu
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
From: ssdupree@eos.ncsu.edu (STEVEN SCOTT DUPREE)
Subject: TEST
Reply-To: ssdupree@eos.ncsu.edu (STEVEN SCOTT DUPREE)
Organization: Project EOS - North Carolina State University
Date: Tue, 14 Apr 1992 20:05:36 GMT

Just a test. Sorry.
Newsgroups: sci.materials
From: me@leidecker.gsfc.nasa.gov (Henning Leidecker)
Subject: Re: Looking for a book with problems on composites
Organization: Goddard Space Flight Center
Date: Fri, 17 Apr 1992 21:13:07 GMT

In article <1992Apr14.010228.13990@athena.mit.edu> zaval@athena.mit.edu  
(Antonis) writes:
> 
> Any suggestions on books with problems (solved or not) on the
> mechanical behavior of composites?

"Composites Design" by Stephen W. Tsai.
Think Composites
P.O. Box 581
Dayton, Ohio 45419
(513) 429-4594

Excellent book --- have your library get it, if they do not already have it.  I  
have no connection with any of Tsai or Think Composites (not that they are  
different).

Henning Leidecker
Newsgroups: sci.materials
From: huff@mcclb0.med.nyu.edu (Edward J. Huff)
Subject: Plastic with glasslike thermal expansion?
Organization: NYU Chemistry Dept
Date: Wed, 15 Apr 1992 18:03:26 GMT


Is there an easy to machine plastic (like acrylic or polycarbonate)
which also expands about the same amount as glass upon heating?

--
Edward J. Huff   huff@mcclb0.med.nyu.edu   (212)998-8465
Keck Laboratory for Biomolecular Imaging
NYU Chemistry Deptartment, 31 Washington Place, New York NY 10003
From: kudzu@tfs.com (Michael Sierchio)
Subject: Re: On Hardware Implementations of DES...
Organization: TRW Financial Systems
Date: Thu, 16 Apr 1992 01:09:49 GMT

In article <1992Apr15.014849.16768@cs.cornell.edu> 
	 wayner@cs.cornell.edu (Peter Wayner) writes:
>
>Does anyone have any good information on the various hardware
>implementation of DES chips that are floating around on the market?
>I'm curious about the price and speed for the usual reasons. 

Western Digital makes one.  BTW, hardware is the *only* way DES is
implemented.  At least according to the spec.
-- 
Michael Sierchio                               TRW Financial Systems
kudzu@tfs.com                                     1947 Center Street
                                             Berkeley, CA 94704-1105
(MKS2)                                                  510.704.3380
From: rja14@cl.cam.ac.uk (Ross Anderson)
Newsgroups: sci.crypt
Subject: One time passwords
Date: 13 Apr 92 11:49:32 GMT
Reply-To: rja14@cl.cam.ac.uk
Organization: U of Cambridge Computer Lab, UK

I went to the `Which Computer Show' in Birmingham last week to see if there
were any new security products. I was disappointed in this - blame the
recession perhaps - but there was a neat system idea from the local Datalock 
distributor. He sends out one-time passwords via the paging system.

A purist might argue that a really serious attacker would monitor the paging
channel. If so, it strikes me that you only need to make a small modification.

Issue each of your users with a (unique) Latin square and a personal number.
Let them use the square to perform substitutions (and if required
permutations  
and hashings as well) of the digits of their personal number, and those they 
get from the pager, to generate a one-time password. Number lengths and
algorithm complexity will depend on your view of (a) the intelligence of
your programmers and (b) the analytic skill and persistence of your opponents.

A lot of firms sell products, such as password generators, which offer better
access security than simple logon passwords. At $20,000 for a controller plus
$200 for each generator, this can add up to too much money for most sites.

However many sites already give out pagers, and those who don't might well do
so if they could get system security as an added benefit.

Ross Anderson
From: rja14@cl.cam.ac.uk (Ross Anderson)
Newsgroups: sci.crypt
Subject: Re: On Hardware Implementations of DES...
Date: 15 Apr 92 13:30:55 GMT
Reply-To: rja14@cl.cam.ac.uk (Ross Anderson)
Organization: U of Cambridge Computer Lab, UK

In <1992Apr15.014849.16768@cs.cornell.edu>, wayner@cs.cornell.edu (Peter
Wayner)
writes:

> Does anyone have any good information on the various hardware
> implementation of DES chips that are floating around on the market?
> I'm curious about the price and speed for the usual reasons. 

I built some stuff using a chip from Cryptech in Brussels which I can't
recommend too highly. It is a DES chip embedded in a microprocessor with
a command set which lets you do all major modes (ECB, CBC and CFB) with
single or double keys and pipelining, off a bus of 8, 16 or 32 bits, with
a throughput of typically 6Mbit/sec.

About the only instruction they don't have is `increment key by 1, encrypt
register X and compare with register Y' (guess why?). Anyway they used to
be on +322 725 4770. The sales guy I dealt with has left now so you'd have 
to ask around from someone to talk to. Their chief scientist is (was?) 
Frank Hoornaert who gave a paper on this chip at Eurocrypt 87.

This is now, as far as I know, the only non-US manufacturer of fast DES 
chips (anyone can make a slow DES chip from a microcontroller). The other,
now discontinued, manufacturer was Robotron of East Germany, who delivered
large quantities of DES chips to the Soviet armed forces (supposedly for
incorporation in the hard disk controllers of PC-XT cloneskies).

Ross
Newsgroups: sci.crypt
From: bfairlan@isis.cs.du.edu (Brian Fairlane)
Subject: Simple encryption(?)
Organization: University of Denver, Dept. of Math & Comp. Sci.
Date: Sat, 11 Apr 92 12:07:43 GMT

I'm about to explain a way to encrypt data, and I expect interested
people to tell me if it's safe, or under what circumstances it would
be safe, or what makes it unsafe etc...
People only interested in putting crypto-beginners down, can continue
reading without replying, thank you.

Ok.

The data is read into memory in blocks of n number of bytes (definable)
it is then "mixed" in a defined order, for example,
a block length of 3 could have a key looking like "3,2,1", meaning
that the third byte in the block will be put at position 1,
the second byte at position 2 (i.e. at the same place) and the first
byte at position 3. 
Then, it is Exclusive-Or'ed with one or more keys, with different
lenghts.
Even if a block isn't dividable with the longest key's length,
the Exclusive-Or'ing will not 'wrap' (start at key's first character again)
Example:
 
  Key: "nisse"
  block: "jajdhidhd0n39dnaldk3j.djsk,dksudj"
  E-OR w/"nissenissenissenissenissenissenissenisse . . ."
                                           ^
                                           | 
                                           -- does not "wrap"
 
Running the null-key/null-byte-file test with this, would, as you see
result in a null-byte file.
But when we're talking of files (text, executables) that's been encrypted
this way, I can't think about how it canbe done, to "crack"/decrypt this.
Even if you know how it is encrypted/have the program/have the source code.

I mean, you don't have the EOR-key, nor the length of the mix-sequence,
nor in what order the bytes should be placed within the mix-sequence
(the block).

Can somebody please, with a mind for mathematics, calculate how
many combinations there are, considering a EOR-key can be of
any length, as well as the mix-sequence, as well as the number of EOR-
keys differ, and the lengths of all keys can be of (any) size/length.
(if somebody feels like challenging their intellect, let's say
 the mix-sequence may be, at most 128 bytes, and three EOR-keys can
 be at most 16 bytes each).
a block length of 3 (mix sequence) can have six combinations;
"1,2,3" "2,3,1" "3,2,1" "2,1,3" "3,1,2" "1,3,2"...

if you begin, systematically, at block lengh 1 up to 128... 
now tell me the number of combinations.
Then add that number to the number of combinations possible from
three individual-length (let's say up to 16 bytes) keys, put
together!

---------
 
To clear a few things here. I hope it's not your "goal" to
have an algorithm, that makes the use of one-key encryptions
safe? That's kind of stupid, I'd say... I'll appreciate anyone who'll
enlighten me on this one as well...
 
      regards,
 
        Brian

b
From: karn@chicago.qualcomm.com (Phil Karn)
Newsgroups: sci.crypt
Subject: Re: On Hardware Implementations of DES...
Date: 16 Apr 92 16:59:45 GMT
Article-I.D.: qualcomm.1992Apr16.165945.23208
Organization: Qualcomm, Inc

In article <1992Apr16.075856.1768@acsu.buffalo.edu> opnsmurf@ubvmsb.cc.buffalo.edu (Da Smurf) writes:
>>BTW, hardware is the *only* way DES is
>>implemented.  At least according to the spec.

>hmm... atleast according to unix man-pages: the des command offers a
>switch to fall back to software implemented des, just incase you dont
>have to hardware installed.

I think point was that NIST does not recognize general purpose
software implementations of DES as meeting the *official* requirements
of the spec, even if they produce exactly the same results. The reason
has to do with the relative ease that a software DES could be
maliciously hacked, or its internal state (e.g., key vectors)
surreptitiously read out by exploiting holes in the host computer's
operating system. DES implemented as ROM firmware in a single-chip
micro *would* meet the test, as this would be much harder to subvert.

This certainly doesn't prevent anyone from using software DES (which
is more properly called "DEA", for Data Encryption Algorithm) if they
don't care what NIST says. But it's probably worth thinking about the
reasons why they have this policy, if only to be aware of the possible
threats in your own situation. E.g., how do you *know* that somebody
hasn't hacked the 'des' command on your workstation to record keys?

Phil
From: rja14@cl.cam.ac.uk (Ross Anderson)
Newsgroups: sci.crypt
Subject: Re: Depth of DES S-Boxes in "Gates"
Date: 14 Apr 92 14:21:18 GMT
Reply-To: rja14@cl.cam.ac.uk (Ross Anderson)
Organization: U of Cambridge Computer Lab, UK

In <1992Apr14.130906.15514@cs.cornell.edu> wayner@cs.cornell.edu (Peter Wayner)
said:

> I remember a discussion not too long ago about the number of logic
> gates necessary to simulate the bits of the DES S-box. Someone
> observed that the DES S-boxes are more complex than random boxes. In
> this case the measure of complexity is the number of logic gates that
> it takes to simulate the result.  Can anyone point me to a reference
> on this subject?

There's a lot of fascinating stuff in switching theory on this topic. It's used
to work out ways of implementing various digital functions in soft logic such
as PLA's and RAM. Try:

`Recent Developments in Switching Theory'
ed: A. Mukhopadhyay
AP, 1971

and

`Spectral Techniques in Digital Logic'
S. L. Hurst, D. M. Miller and J. C. Muzio
AP, 1985

I suspect that a lot of this stuff could be used in cryptanalysis if one
had the time to sit down and work it all out.

Ross Anderson
From: ahaley@abcl.co.uk (Andrew Haley)
Newsgroups: sci.crypt
Subject: Re: Try-out
Date: 10 Apr 92 09:17:21 GMT
Organization: EO Computer Limited, Cambridge, UK

in Message-ID: <1992Apr9.204018.12320@mnemosyne.cs.du.edu> from
bfairlan@isis.cs.du.edu (Brian Fairlane):

> Assume I had a fast, simple and "secure" encryption algorithm, can I
> somewhere, somehow "try this out"? I.e. send an encrypted file
> to some pattern research/cryptology place, and ask them to decrypt it,
> back to whatever it was before (plain textfiles) encrypting it.

That's not a good test.  A better test is described below.

> I, who created it, can't in no way figure out how it could be done, but
> I want some independant, professional people to tell if it is.

This takes time.  The differential cryptanalytic attack on FEAL-8 was
not published for a couple of years.  This is the minimum amount of
time you ought to wait between publishing details of an algorithm and
using it.

> Interested people/companies: Send me textfiles, and I will encrypt
>                              them and send them back (uu-encoded).
>                              Of course I will use the same key for all
>                              your files, so you have One chance of making
>                              it (don't ask me how though).

No, that's not a valid test.  What you must do is:

	1. Publish the exact details of your algorithm.
	2. Get someone to send you some text, which you encipher.
	   (this text can be very large.)
	3. Send the enciphered text back to the tester.
	   The tester tries to find the key.
	4. Repeat steps 2 and 3 until the tester is satisfied.

If you do not publish the details of your algorithm, you're just
promoting Security Through Obscurity.  And if you can't allow multiple
adaptive attacks, your encryption algorithm isn't up to the job.

The "best" way to "try out" an encryption algorithm is to submit a
paper describing it to one of the Crypto conferences (Crypto,
Eurocrypt, Asiacrypt.)  If you're lucky :-), one of the attendees
might be able to break your algorithm there and then (this has
happened.)  Alternatively try Cryptologia or the Journal of
Cryptology.  Be warned, such journals tend to have a very long lead
time.

> Sceptics; No, it's not a (key) == (length_of_file) "algorithm".
> It uses "normal" keys in special ways.

Good luck.
Andrew. (a skeptic :-)
Newsgroups: sci.crypt
From: graham@sees.bangor.ac.uk (The Land of Confusion)
Subject: Re: Random-dot stereograms
Organization: University of Wales
Date: Tue, 7 Apr 1992 16:28:17 GMT

In article <6568@skye.ed.ac.uk>, richard@aiai.ed.ac.uk (Richard Tobin) writes:
> It occurs to me that random-dot stereograms could be used for
> transmitting small amounts of information securely.  The recipient
> would be provided in advance with one half of the stereogram, and the
> other half would be constructed when needed.  

As the information in a random dot stereogram is stored in the disparities
between corresponding dots in the pair of images, isn't it necessary to
have the plain text in advance of constructing *both* images? This seems
to indicate that the `key' half is not in fact independent of the information 
to be securely transmitted and could therefore not be provided `in advance'.

--
graham

 \/                                                                          \/
 /\                   Motto withheld pending investigation                   /\
 \/                                                                          \/