HDTenEightyP/NetNews huggingface dataset:
From: acampane@magnus.acs.ohio-state.edu (Angelo Campanella)
Subject: Re: Warm water freezes first. why?
Followup-To:                same
Keywords:     ice bubbles freeze time
Organization: The Ohio State University
Distribution:              usa
Date: Sun, 20 Dec 1992 05:20:48 GMT



If the warm water is degassed via the warming, then when cooler, its thermal
conductivity will be greter than water which may evolve some gas to become
entrained bubbles with the attendant decrease in the effective thermal
conductivity of the by then partly frozen cube. 

If this be true, then one should observe that the cold water sample will 
form the first traces of ice, but somewhere around 30% to 50% frozen,
the cold water sample, by then containing some bubbles, will freeze more 
slowly.

Meanwhile, the sample of previously hot water will remain clear of bubbles 
and proceed uniformly to become 100% frozen first.

Anyone out ther witha  freezer adn stopwatch??

Ang.
Newsgroups: sci.engr.mech
From: jbibb@eng.auburn.edu (John S. Bibb)
Subject: Re: SPAR Buoy
Reply-To: jbibb@eng.auburn.edu
Organization: Auburn University Engineering
Date: Wed, 16 Dec 1992 02:22:50 GMT

In article 0@mpl.ucsd.edu, eric@mpl.ucsd.edu (Eric Terrill) writes:
> Hello,
> I am currently designing a SPAR buoy that is to be deployed next year with
> an array of oceanographic gear next year.  I have been looking for 
> recent design reports, papers, etc. on this subject and would like more 
> references.  I've decided to have it built of steel so I am also looking for 
> references that specifically deal with corrosion resistant design.  Are 
> sacrificial zinc anodes and/or zinc chromate paint adequate for a four month 
> deployment?  


Zinc anodes are commonly used on both sail boats and power boats with a great degree
of success.  They come in several different sizes and shapes depending on the 
application.  Knowing several people with steel hulled boats, I have seen that they
tend to use more zincs that fiberglass boats, but I think that for a spar bouy
you would not need a very big zinc for a four month test.  I would recommend marine
grade primer and antifouling paint (often a good bit of zinc in there too).  You might
want to check with a local boat yard for excess paint (It sounds like you do not need
much), and advice on best performance for your area.

Good luck!!
J. Bibb
Xref: sparky sci.engr.mech:668 sci.engr.civil:578
From: eric@mpl.ucsd.edu (Eric Terrill)
Newsgroups: sci.engr.mech,sci.engr.civil
Subject: SPAR Buoy
Date: 14 Dec 1992 18:24:15 GMT
Organization: Scripps Institution of Oceanography
NNTP-Posting-Host: kiko.ucsd.edu

Hello,
I am currently designing a SPAR buoy that is to be deployed next year with
an array of oceanographic gear next year.  I have been looking for 
recent design reports, papers, etc. on this subject and would like more 
references.  I've decided to have it built of steel so I am also looking for 
references that specifically deal with corrosion resistant design.  Are 
sacrificial zinc anodes and/or zinc chromate paint adequate for a four month 
deployment?  
-------------------------------------------------------------------------
Eric J. Terrill						et@mpl.ucsd.edu
Scripps Institution of Oceanography, 0213	        (619) 534-1085
La Jolla, CA 92093
Newsgroups: sci.engr.mech
From: rizzo@cbnewsf.cb.att.com (anthony.r.rizzo)
Subject: Re: Bovine scatalogy.  was: Warm water freezes first. why?
Organization: AT&T
Date: Fri, 18 Dec 1992 15:16:40 GMT

In article <1992Dec17.162456.214@xxxxx.arc.ab.ca> (xxxx yyyyy) writes:
>In article <1flklaINNg2l@usenet.INS.CWRU.Edu> xxx@r2d2.eeap.cwru.edu (xxx
>yyyy) writes:
>>This question is actually asked in one of the Heat Transfer classic text
>books.
>>I belive it was Holman. This is what I think:
>>
>
>Yes, would INITIALLY have a higher temperature gradient, but....

10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0:   and we have ignition....

The names have been changed to protect the innocent.  Please note that
the first law, which, if I recall correctly, is a statement of 
conservation of energy, has NOT been repealed!

I find it odd that I've seen no technical literature on this issue
that has survived the peer review process.  I find it equally
odd that no products exist that take advantage of the "faster"
freezing qualities of hot water.  Can we not move on to
more technically correct ground?  Perhaps, we should form
a new newsgroup:  sci.engr.mech.pseudo

Tony Rizzo (att.com!hogpb!rizzo)


Newsgroups: sci.engr.mech
From: mike@drseus.jsc.nasa.gov (Mike Ross)
Subject: Re: Warm water freezes first. why?
Organization: Lockheed Engineering & Sciences Company
Date: Fri, 18 Dec 1992 14:38:13 GMT

In article <1992Dec17.162456.214@janus.arc.ab.ca> morgan@arc.ab.ca (Sean Morgan) writes:
>In article <1flklaINNg2l@usenet.INS.CWRU.Edu> sxs@r2d2.eeap.cwru.edu (Soheil
>Sayeh) writes:
>>This question is actually asked in one of the Heat Transfer classic text
>books.
>>I belive it was Holman. This is what I think:
>>
>>The combined effect of higher temperature gradient and evaporation is the
>cause.
>>because of low temperature in the freezer the air is extremely dry, so the hot
>>water starts to evaporate, and at the same time it cools down. what happens is
>
>>,we are freezing less amount of water in the warm tray. and the amount of
>>heat requred to do it is less than the cold tray.
>>
>
>Yes, would INITIALLY have a higher temperature gradient, but after a few hours
>the warm water would be where the cold water was to start with!
>
>I thought it was because there are fewer dissolved gases in the warm water. 
>Now how that affects the cooling rate, I don't know.  Can't see how it would
>reduce the specific heat very much.
>

I'm the original poster who asked this question.  This is the biggest
thread I've ever generated.  A thoroughly interesting engineering
discussion by a lot of learned individuals regarding my question!

It appears the answer is as many people have pointed out, that the
evaporation rate causes there to be less water when the hot tray
reaches the temperature that the cold tray started out from, and so
less energy actually needed to be removed to freeze.  I had been told
that the phenomenon could be explained via differential equations,
so the evaporation rate fits that.

Of course, I'm still drawing my conclusions from the net.discussion,
I've not checked that explanation, it just seems the most plausible.
The rationale that the warm water makes better contact with the metal
tray doesn't wash, because the cold water would also melt the ice on the
grill and get good contact.

My thanks to all the learned participants from this auguste group.


-- 
******************************** mike@drseus.jsc.nasa.gov *****
* Michael L. Ross/C33 | Lockheed Engineering & Sciences Co.   *
* Robotics Department | 2400 Nasa Rd. 1, Houston, TX 77062    *
*(713)333-7094 voice,(713)333-7201 fax**********boring, eh?****
Newsgroups: sci.engr.mech
From: kk881595@longs.LANCE.ColoState.Edu (kevin knappmiller)
Subject: Re: question about 'apparent' temperature
Date: Fri, 18 Dec 1992 17:48:24 GMT
Reply-To: kk881595@longs.LANCE.ColoState.Edu
Organization: Colorado State U. Engineering College

In article <535@blue.cis.pitt.edu>, tmkst6+@pitt.edu (Theodore M Kostek) writes:
|> All this talk about the ice cubes and classrooms has me wondering about 
|> a related problem.  I'm only a 1st term junior, and haven't had
|> any heat transfer classes, so I'm not sure if I have this right.  
|> My question concerns wind chill and relative humidity as they relate 
|> to the apparent temperature.  When the weather report gives the temp with 
|> wind chill factor (ex 40, 20 with wind chill), are they saying that the heat 
|> transfer rate from your body is the same as if the air was 20 degrees but
|> still? 

Essentially.

|> Similarly when it very humid, say 70 degrees but feels like 80, does 
|> this mean that the heat transfer rate is the same as if it were a lower 
|> humidty at 80 degrees?
|> 
In this range one is more concerned with "comfort" than heat
transfer. The criteria here are much more empirical than
wind chill.  The effect of humidity is much harder to quantify.
If you are interested look in chapter 31 of the ASHRAE handbook
of fundamentals.

Kevin Knappmiller
Solar Lab
Colorado State University
Fort Collins, CO  80523
(303)491-8215
kk881595@longs.lance.colostate.edu
Newsgroups: sci.engr.mech
Subject: Re: Warm water freezes first. why?
From: morgan@arc.ab.ca (Sean Morgan)
Date: 17 Dec 92 16:24:55 MDT
Distribution: world
Organization: Alberta Research Council

In article <1flklaINNg2l@usenet.INS.CWRU.Edu> sxs@r2d2.eeap.cwru.edu (Soheil
Sayeh) writes:
>This question is actually asked in one of the Heat Transfer classic text
books.
>I belive it was Holman. This is what I think:
>
>The combined effect of higher temperature gradient and evaporation is the
cause.
>because of low temperature in the freezer the air is extremely dry, so the hot
>water starts to evaporate, and at the same time it cools down. what happens is

>,we are freezing less amount of water in the warm tray. and the amount of
>heat requred to do it is less than the cold tray.
>
>I hope I could explain clearly what I meant.
>
>have a good one,
>
>Soheil.

Yes, would INITIALLY have a higher temperature gradient, but after a few hours
the warm water would be where the cold water was to start with!

I thought it was because there are fewer dissolved gases in the warm water. 
Now how that affects the cooling rate, I don't know.  Can't see how it would
reduce the specific heat very much.
-----------------+-------------------------------
Sean Morgan      |  ALBERTA  6815 - 8 Street N.E.
                 | RESEARCH  Calgary, AB, Canada
morgan@arc.ab.ca |  COUNCIL  T2E 7H7
From: bluelobster+@CMU.EDU (David O Hunt)
Newsgroups: sci.engr.mech
Subject: SME student membership
Date: 16 Dec 92 17:44:22 GMT
Article-I.D.: andrew.of=zSKC00XsFI64kQs
Organization: Carnegie Mellon, Pittsburgh, PA


Could some kind soul tell me where I could get info about becoming a
student member of the Society of Manufacturing Engineers?

Thanks!

David Hunt
bluelobster+@cmu.edu
From: choy@skorpio.usask.ca (I am a terminator.)
Newsgroups: sci.engr
Subject: I don't want to keep looking for new jobs.
Date: 18 Dec 1992 18:02:14 GMT
Organization: University of Saskatchewan, Saskatoon, Canada
Distribution: world
NNTP-Posting-Host: skorpio.usask.ca

The latest issue of Spectrum discusses the conversion of engineers from
military work to civilian work. One of the articles says that
many engineers could go through 10-12 jobs in a lifetime. Companies tend
to contract work out so engineers can't expect to work in a stable
company. They have to learn to manage themselves and go around looking
for work. Having to look for work every few years is a royal pain in the
ass. Upper management should be getting enough work to keep their
engineers employed. There's a few engineering firms in town. They bid
on contracts and employ engineers to grind out the details. An
engineering friend of mine was laid off from one such company because it
didn't have enough work to do. Now my friend has gone out and found
people wanting to contract work out. What's this big company doing?
It's gotten so big that it doesn't even know how to get work. They just
bury themselves with paperwork and legal matters.

Henry Choy
choy@cs.usask.ca
Newsgroups: sci.engr.control
From: jchen@tomahawk.me.gu.edu.au (Jinghong CHEN)
Subject: Re: Riccati Equation 
Organization: Griffith University, Brisbane, Australia
Date: Wed, 16 Dec 92 21:29:15 GMT

In article <1992Dec15.211306.9379@news.nd.edu> dnewell@twain.helios.nd.edu (devin newell) writes:
>I am trying to find a decent program that can be used to solve the Algebraic Riccati Equation.  In the past I have used Matlab with a fair
>amount of success, however, the Matlab overhead is killing me in terms of
>running time.  I would prefer something in Fortran, however, Pascal or C
>would also be suitable.  

In netlib, the following software is available:

IEEECSS/CASCADE   "Computer-Aided Systems and Control Analysis and Design
        Environment"; contributed by J. D. Birdwell.
        Cascade Version SUN0.9  June 23, 1988

in which, Riccati Equation Solver is included. It was written by Fortran
and based on LINPACK and EISPACK.

---------------------------------------------------------------------------
J.CHEN                               |E-MAIL: jchen@tomahawk.me.gu.edu.au
School of Microelectronic Engineering| Phone: +61-7-8755050
Faculty of Science and Technology    |   Fax: +61-7-8755198
Griffith University                  |   Fax: +61-7-8755050
Nathan, QLD 4111, Australia          | 
---------------------------------------------------------------------------
-- 
ehunjfnlkdf dfdfjnlkdfl
Newsgroups: sci.engr.control
From: stote@tomcat.den.mmc.com (M. Stote)
Subject: Re: Riccati Equation 
Organization: Martin Marietta Astronautics Group
Date: Thu, 17 Dec 1992 00:10:28 GMT

In article <1992Dec16.212915.26846@griffin.itc.gu.edu.au>, jchen@tomahawk.me.gu.edu.au (Jinghong CHEN) writes:
|> In article <1992Dec15.211306.9379@news.nd.edu> dnewell@twain.helios.nd.edu (devin newell) writes:
|> >I am trying to find a decent program that can be used to solve the Algebraic Riccati Equation.  In the past I have used Matlab with a fair
|> >amount of success, however, the Matlab overhead is killing me in terms of
|> >running time.  I would prefer something in Fortran, however, Pascal or C
|> >would also be suitable.  
|> 
|> In netlib, the following software is available:
|> 
|> IEEECSS/CASCADE   "Computer-Aided Systems and Control Analysis and Design
|>         Environment"; contributed by J. D. Birdwell.
|>         Cascade Version SUN0.9  June 23, 1988
|> 
|> in which, Riccati Equation Solver is included. It was written by Fortran
|> and based on LINPACK and EISPACK.
|> 
|> ---------------------------------------------------------------------------
|> J.CHEN                               |E-MAIL: jchen@tomahawk.me.gu.edu.au
|> School of Microelectronic Engineering| Phone: +61-7-8755050
|> Faculty of Science and Technology    |   Fax: +61-7-8755198
|> Griffith University                  |   Fax: +61-7-8755050
|> Nathan, QLD 4111, Australia          | 
|> ---------------------------------------------------------------------------
|> -- 
|> ehunjfnlkdf dfdfjnlkdfl


Is this package at all related to the CASCADE software package developed at
Grumman with some (I think) cooperation from Univ Maryland ?  
I used Grumman's version back in the mid 80's.
--
Mike Stoughton
stote@den.mmc.com
From: bush@ces.cwru.edu (Stephen Bush)
Newsgroups: sci.engr.control
Subject: Control Theory applied to Computer Network Management
Date: 14 Dec 1992 15:34:05 GMT
Organization: Computer Engineering and Science, Case Western Reserve University
Distribution: world
NNTP-Posting-Host: easy.ces.cwru.edu


I have received many requests for information about
control theory applied to computer network management,
however, I have not received any significant 
information.

I will be happy to post a summary if/when I receive 
anything.


				Thanks,
				Steve

Newsgroups: sci.engr.control
From: chu_c@IASTATE.EDU (Chao-Hsien Chu)
Subject: Re: Neuro-Fuzzy (Kohonen)
Reply-To: chu_c@IASTATE.EDU (Chao-Hsien Chu)
Organization: Iowa State University
Date: Wed, 16 Dec 1992 16:14:15 GMT

This topic seems very interesting. Could you summarize them after?
Also, you mentioned the report for T2 from the University of 
Dortmund. Could you provide more information about it and where
who can I obtian the report? Thanks!

Chao-Hsien Chu
Department of Management
College of Business
Iowa State University
Ames, Iowa 50011, USA
E-mail: chu_c@iastate.edu
Newsgroups: sci.engr.control
From: hueske@iw.uni-hannover.de (Marc Hueske)
Subject: Neuro-Fuzzy (Kohonen)
Reply-To: hueske@iw.uni-hannover.de
Organization: Institut fuer Werkstoffkunde, Uni Hannover
Date: Wed, 16 Dec 1992 12:19:58 GMT

Help needed !
I am looking for references about Kohonen's feature maps used to extract
rules and membership funcitons for a fuzzy logic controller (vehicle control)
from example data. Is it possible to use the feature maps to adaptively change the controller's parameters (membership functions, rules) during the operation or is the 
learning ability to slow?
Thanks in advance,

Marc

P.S.: I already have the report ForT2 from the University of Dortmund.

----------------------------------------------------------------------
|  Marc Hueske                    |  Tel: INT-49-511-762-3906        |
|  Universitaet Hannover          |  Fax: INT-49-511-762-5245        |
|  Institut fuer Werkstoffkunde   |  Email: hueske@iw.uni-hannover.de|
|  Fachgruppe Unterwassertechnik  |                                  |                                       |  Appelstr. 11a                  |                                  |                                     |W-3000 Hannover, GERMANY         |                                  |                                       ----------------------------------------------------------------------



Xref: sparky sci.engr.control:371 alt.control-theory:6
From: saleh@ece.orst.edu (Hassan Saleh)
Newsgroups: sci.engr.control,alt.control-theory
Subject: Nonlinear optimal control program available ?
Date: 19 Dec 92 22:47:29 GMT
Article-I.D.: flop.1h08q1INNl15
Distribution: world
Organization: Oregon State University, Corvallis
NNTP-Posting-Host: hobo.ece.orst.edu


   Is there any public domain program available for the solution
   of nonlinear optimal control problems ? I tried using colnew
   to solve the resulting two-point boundary value problems but
   I always get "singular elimination matrix" some where.

   H. I. SALEH
Organization: Penn State University
Date: Mon, 14 Dec 1992 17:23:18 EST
From: <AXB30@psuvm.psu.edu>
Newsgroups: sci.engr.control
Subject: Re: DES Control Books

A good reference book on DEDS: "Modeling and Control of Automated
Manufacturing Systems", IEEE Computer Society Press Tutorial, by
Alan A. Desrochers.  This book provides a good overview of the
different methods available in DEDS.
 - Atle
Newsgroups: sci.engr.control
From: ics.rick@Control.Com (Richard F. Kaerwer)
Newsgroups: sci.engr.control
Subject: Re: Chemical Engineering Newsgroup?
Date: 16 Dec 92 17:20:11 GMT
Article-I.D.: Control.c1XVVB1w164w
Reply-To: ics.rick@control.com
Organization: Industrial Computing Society

> >>Is this the closest thing to a Chemical Engineering newsgroup?  I am intere
> >>in process control - chemical process control that is.  I've seen some post
> >>on fuzzy logic on the comp.ai newsgroup.

You might also want to look at ALT.INDUSTRIAL.COMPUTING 
That newsgroup deals with computers in industry and touches on 
process control.  It's "sponsored" (?) by the Industrial Computing 
Society.

--Rick Kaerwer, ICI Films, Hopewell, VA  (a chemical engineer)
Newsgroups: sci.engr.control
From: dnewell@twain.helios.nd.edu (devin newell)
Subject: Riccati Equation 
Reply-To: dnewell@twain.helios.nd.edu (devin newell)
Organization: University of Notre Dame, Notre Dame
Date: Tue, 15 Dec 1992 21:13:06 GMT

	I am trying to find a decent program that can be used to solve the Algebraic Riccati Equation.  In the past I have used Matlab with a fair
amount of success, however, the Matlab overhead is killing me in terms of
running time.  I would prefer something in Fortran, however, Pascal or C
would also be suitable.  


Thanks in advance for any and all help.

Devin
Newsgroups: sci.engr.control
From: vellmer@iw.uni-hannover.de (Ulrich Vellmer)
Subject: guide and control system
Reply-To: vellmer@iw.uni-hannover.de
Organization: Institut fuer Werkstoffkunde, Uni Hannover
Date: Tue, 15 Dec 1992 14:46:30 GMT


Hi,

i'm looking for references about concepts of 'intelligent' guide and control
systems for vehicles (especially autonomous underwater vehicle (auv), remotely 
operated vehicle (rov)).

I'd be very thankful.


   Greetings,
             Ulrich


********************vellmer@iw.uni-hannover.de*********************
*                                                                 *
* Ulrich Vellmer                         Tel: INT-49-511-762-3906 *
* Institut fuer Werkstoffkunde           FAX: INT-49-511-762-5245 *
* Universtitaet Hannover                                          *
* Appelstrasse 11 A                                               *
* W 3000 Hannnover 1; Germany                                     *
*******************************************************************

Newsgroups: sci.engr.control
From: rairan@ecf.toronto.edu (RAI Ranjan)
Subject: DES Control Books
Organization: University of Toronto, Engineering Computing Facility
Date: Mon, 14 Dec 1992 16:36:28 GMT

Could someone out there recommend some good introductory books for 
Discrete Event System control?

Thanks.

-- 
Ranjan Rai                             <rairan@ecf.toronto.edu> 
Engineering Science 9T3                <rr@odin.control.toronto.edu> 
University of Toronto                    
Xref: sparky sci.engr.control:372 alt.control-theory:7
From: jwiegand@moe.eng.temple.edu (James Wiegand)
Newsgroups: sci.engr.control,alt.control-theory
Subject: Re: Nonlinear optimal control program available ?
Date: 20 Dec 92 05:12:46 GMT
Organization: Temple University EE Dept.

In article <1h08q1INNl15@flop.ENGR.ORST.EDU> saleh@ece.orst.edu (Hassan Saleh) writes:
>
>   Is there any public domain program available for the solution
>   of nonlinear optimal control problems ? I tried using colnew
>   to solve the resulting two-point boundary value problems but
>   I always get "singular elimination matrix" some where.
>
>   H. I. SALEH

According to what I've heard, there is no single method for nonlinear
control systems in general. 

jim
... willing to be proven wrong.
Newsgroups: sci.engr.control
From: edjans01@orion.spd.louisville.edu (David Jansing)
Subject: Re: Riccati Equation 
Date: Wed, 16 Dec 1992 16:05:05 GMT
Organization: University of Louisville

In <1992Dec15.211306.9379@news.nd.edu> dnewell@twain.helios.nd.edu (devin newell) writes:

>	I am trying to find a decent program that can be used to solve the Algebraic Riccati Equation.  In the past I have used Matlab with a fair
>amount of success, however, the Matlab overhead is killing me in terms of
>running time.  I would prefer something in Fortran, however, Pascal or C
>would also be suitable.  

Did you look in _Numerical Recipies in C_?  There is a new edition and I
would be willing to bet that if they did have a Ricatti Eqn. solution
directly, that you could build one easily with the matrix operations
sections that they have in the book.

-- 
------------------------------------------------------------------------------
Dave Jansing  |  University of Louisville  |  Dept. of Electrical Engineering
------------------------------------------------------------------------------
"The diamond in the rough . . ." - _Aladdin_          #include <disclaimer.h>
------------------------------------------------------------------------------
From: rajkumar@ece.orst.edu (Rajkumar Vedam)
Newsgroups: sci.engr.control
Subject: Discretization of Nonlinear Systems
Keywords: Discretization, Nonlinear Systems
Date: 11 Dec 92 18:22:03 GMT
Article-I.D.: flop.1gam8bINNbcc
Distribution: world
Organization: Oregon State University, Corvallis
NNTP-Posting-Host: sardine.ece.orst.edu
Originator: rajkumar@sardine.ECE.ORST.EDU


I would like references to literature on the 
discretization of nonlinear systems of the form:

dX/dt = F(X,u)   (time-invariant, nonlinear)

If you know of any, please post/reply by e-mail.
Thanks.


--------------
Rajkumar Vedam
(rajkumar@ece.orst.edu)
From: choy@skorpio.usask.ca (I am a terminator.)
Newsgroups: sci.engr
Subject: I want to learn engineering
Date: 20 Dec 1992 00:19:03 GMT
Organization: University of Saskatchewan, Saskatoon, Canada
Distribution: world
NNTP-Posting-Host: skorpio.usask.ca

The present system does not make it easy to learn engineering on my own.
Textbooks are hard to understand. They are incomplete. They are very
hard to work with. The education I got doesn't do justice to engineering.

Education isn't merely the basic undergraduate training. More advanced
reference material let's me down too.

Henry Choy
choy@cs.usask.ca
Newsgroups: sci.engr