HDTenEightyP/NetNews huggingface dataset:
From: dsza@elm.lle.rochester.edu (Tony De Souza)
Newsgroups: sci.engr.mech
Subject: us government
Summary: citizenship and jobs
Keywords: jobs
Date: 31 Dec 92 16:20:54 GMT
Organization: University of Rochester - Rochester, New York

I currently work ath the Laboratory for Laser energetics at the 
University of Rochester.  We are currently working on upgrading
our laser system.  The expereince I get here is great (My first 
job since graduating in Dec 1990), but it seems that if I want 
to continue doing what I enjoy so much here I have to work for 
the government, which is fine.  Only problem is I am neither a
US citizen nor a permenant residence.  I am on a H-1B visa.  
Everytime I see jobs advertised by the government it specifically 
states US citizenship required.  Anyone know how cast in stone 
this is?  Just curious.  I will continue to apply for jobs I like 
as they come along, but it would be interesting to know.
Thanks in advance

--
Tony DeSouza                                                           \ | /
Winners were once dreamers --------------------------------------------- @ -
University of Rochester Laboratory for Laser Energetics                / | \
dsza@elm.lle.rochester.edu		"Ignorance has been good to me"
Newsgroups: sci.engr.mech
From: dbliss@fox.nstn.ns.ca (Doug Bliss)
Subject: Domestic hot water heaters - oil vs. electric
Organization: Environment Canada
Date: Mon, 21 Dec 1992 16:10:22 GMT

I have heard that oil-fired domestic hot water heaters are very ineffecient (
20-30% efficiency) compared to electric hot water heaters.  Does anyone have 
any information on efficiencies and heat losses expected from these types of 
hot water heaters?
Newsgroups: sci.engr.mech,sci.engr,sci.physics,sci.engr.civil
From: act@sun.ipl.rpi.edu (just another programmer)
Subject: Info on elastomers
Keywords: elastomers, torsion, vibrations
Date: Wed, 23 Dec 1992 17:19:55 GMT

I am posting this for an unfortunate body without access to the net.

He is looking for books, journals, and articles rearding elastors.

Excuse me, elastomers.  He is interested in getting info on elastomers,
both natural and synthetic, under torsional loads.  He also through some words
like shear and precipitous at me.

If you have any questions or info thanks a great deal, and I'll try to get 
questions answered.

Thanks
Grant
From: daniel@redwood.ppc.ubc.ca (Daniel Ouellet)
Newsgroups: sci.engr.mech
Subject: Re: What % of engineers are women?
Date: 29 Dec 1992 16:27:39 GMT
Organization: University of B.C. Pulp & Paper Centre
Distribution: usa
NNTP-Posting-Host: redwood.ppc.ubc.ca

During my bachelor degree, there was 1.4% women in my class (Mechanical engineering), and her
name was Lucie 8^)

-- 
----------------------------------------------------------------------
Daniel Ouellet, Research Associate
Pulp and Paper Centre, University of British Columbia
2385 East Mall, Vancouver, BC, Canada V6T 1Z4
Tel:(604)822-8240   Fax:(604)822-8563   Email: daniel@ppc.ubc.ca
Newsgroups: sci.engr.mech
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: Re: What % of engineers are women?
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Distribution: usa
Date: Mon, 28 Dec 1992 17:59:31 GMT


During my graduate school days, 25% of the graduate school were women.  That was
circa 1983.
-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
Newsgroups: sci.engr.mech
From: chenm@newton.ccs.tuns.ca (Ming chen)
Subject: Inquiry: Contaminant Transport Models
Date: Wed, 23 Dec 1992 23:52:01 GMT
Distribution: sci.engr.civil, sci.engr.chem, sci.engr.mech
Organization: Technical University of Nova Scotia, Halifax, N.S.

 Hello, everyone.

 I am currently looking for some contaminant transport models. 
 I wander if there is any ftp sites/archives for such models or
 other numerical models (finite elements, finite difference or
 boundary elements).

 Thanks in advance.

 /ming

 chenm@tuns.ca
From: robear@ccwf.cc.utexas.edu (Jay Michael)
Newsgroups: sci.engr.mech
Subject: Freezing water
Date: 24 Dec 92 06:53:52 GMT
Organization: The University of Texas at Austin, Austin TX

I am still rather surprised at the thread about warm water freezing faster.
I was under the distinct impression that it was an old wives tale, and
that warm water will always take longer to freeze than cold water.  This
is a rather basic and obvious conclusion using simple thermodynamics.

I will concede that warm water will freeze faster, in the sense that the
heat transfer _rate_ will be quite quicker for the warm water than the cold,
and as it cools off this rate will slow down.

Was there any conclusion that we all had aggreed upon?  I think I need
a recap or something.

Jay Michael

Newsgroups: sci.engr
From: cuikrnx@gsusgi2.gsu.edu (Keith Nelms)
Subject: Re: ASHRAE 93 ??
Organization: Georgia State University
Date: Wed, 30 Dec 1992 03:08:13 GMT

ninassup@athena.mit.edu (Nikos I Nassuphis) writes:


>I need to find the list of participants to
>ASHRAE 93, taking place in Chicago in the
>last week of January.

Don't know if this helps or not, but my Atlanta phonebook (where ASHRAE is
headquartered, I believe) lists their number as 404/636-8400.

Regards, 

Keith

\\\\  Keith R. Nelms, PE       \\\  Doctoral Student         \\\\
 \\\\  Information Management   \\\  Instructional Technology \\\\
  \\\\  Georgia Department of    \\\  Georgia State University \\\\
   \\\\  Community Affairs        \\\  cuikrnx@gsuvm1.gsu.edu   \\\\
    \\\\  w:404-656-3879 (Atlanta) \\\  h:404-932-2935  (Buford) \\\\

Newsgroups: sci.engr
From: sysmgr@king.eng.umd.edu (Doug Mohney)
Subject: ABAQUS performance?
Date: Mon, 21 Dec 92 16:34:09 GMT
Organization: Computer Aided Design Lab, U. of Maryland College Park
Reply-To: sysmgr@king.eng.umd.edu

Anyone seen ABAQUS thrash itself to a crawl on a VAX/VMS system? The model
in question cruises along happily for 30-40 minutes, then the disk I/O gets
out of hand and it gets very s-l-o-w.

				doug

                    I have talked to Ehud, and lived.
  -- >                  SYSMGR@CADLAB.ENG.UMD.EDU                        < --
Newsgroups: sci.engr.control,alt.control-theory
From: culwick@bnlux1.bnl.gov (B Bryan Culwick)
Subject: Re: Nonlinear optimal control program available ?
Organization: Brookhaven National Laboratory, Upton, NY 11973
Date: Wed, 23 Dec 1992 15:49:11 GMT

In article <1992Dec22.204244.20869@magnus.acs.ohio-state.edu> acampane@magnus.acs.ohio-state.edu (Angelo Campanella) writes:
>
>A century or so a fellow by the name of Watts had a nonlinear control problem 
>where he was employed to turn a steam valve on and off repeatedly.  Being 
>naturally lazy, he invented a leverage sysytem for the machine to do it for 
>itself.  He was then credited for inventing the steam engine.  I rather suspect
>he went through an evolution process where he needed at times too much memory 
>and too much space.   We seem to have compressed those requirments in 
>intervening centuries...

  James Watt, not Watts and, in any case, it was Newcomen!!
From: rhelps@bones.et.byu.edu (Richard Helps)
Newsgroups: sci.engr.control
Subject: Re: LabVIEW for control
Date: 24 Dec 92 15:42:01 GMT
Organization: Brigham Young University, Provo UT USA

In article <1992Dec22.143620.19334@udel.edu> chen@huey.udel.edu (Shoupu Chen) writes:
>I am interested in knowing of any of you readers has had experience of or
>knowledge of using LabVIEW to impletment a control system in the real time
>process, for example, to control a robot arm.
>
>Please send your comments directly to my account, thanks alot.
>
>Shoupu
>
>Shoupu Chen
>Applied Science and Engineering Center
>University of Delaware
>P.O. Box 269
>Wilmington, DE 19899
>
>chen@asel.udel.edu

Please post a summary to the net if you get responses to this
Thanks.
Richard Helps BYU Provo UT
Newsgroups: sci.engr.control
From: asif@mecad.uta.edu (Asif Mohammed)
Subject: help
Organization: University of Texas at Arlington
Date: Mon, 21 Dec 1992 20:11:21 GMT

Hi,
     I need some help regarding a control's package in mathematica  
called COSYPAK. If someone can mail this package to me his/her help  
would be greately appreciated.   
                     thanx
                            asif

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`
From: adams@liszt.berkeley.edu (Adam L. Schwartz)
Newsgroups: sci.engr.control
Subject: Re: Nonlinear optimal control program available ?
Date: 21 Dec 92 20:31:00 GMT
Organization: U.C. Berkeley -- ERL

In article <Dec.21.13.36.30.1992.21577@gandalf.rutgers.edu> rgonzal@gandalf.rutgers.edu (Ralph Gonzalez) writes:
>jwiegand@moe.eng.temple.edu (James Wiegand) writes:
>
>I'm not an expert in this area, but I think the only general-purpose
>approach for nonlinear control systems is the brute-force approach.

Like any other optimization problem, there are much more intelligent
means for solving optimal control problems than brute force.  Take
a look at "Computational Methods in Optimization," Polak, 1971.


>In the 60's, King-Sun Fu and others took the approach of partitioning
>state space, and "learning" the (sub) optimal control action for
>each element of the partition, on-line. The resulting "lookup-table"
>allows the controller to select the best control action for each
>point in state space. 

There was another approach similar to this that was recently suggested
which is done off-line (no learning involved).  It is based on iteratively
solving the Dynamic Program which arrises out of the optimal control 
problem.  The article is "On the Application of Iterative Dynamic
Programming to Singular Optimal Control Problems," R. Luus, IEEE Trans.
on Autom. Cntrl., Nov. 1992, pp. 1802-1806.  I'm not necessarily suggesting
this method, though.

-Adam Schwartz
adams@robotics.berkeley.edu
U.C. Berkeley
Newsgroups: sci.engr.control,alt.control-theory
From: adams@bellini.berkeley.edu (Adam L. Schwartz)
Subject: Re: Nonlinear optimal control program available ?
Organization: U.C. Berkeley -- ERL
Date: Mon, 21 Dec 1992 18:21:51 GMT

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

I'm working on a nonlinear optimal control package now, but it will be
some time before I'm finished.  If you want to solve your problem by
solving the BVP which arises out of the Euler-Lagrange equations, you
must make sure that the sum of the Jacobian matrices of the initial
and final conditions for the BVP is non-singular.  If it isn't, you
must use a smooth, time-dependent (non-singular, for all time of interest)
state-transformation which results in the sum of the Jacobians being
non-singular.  This is usually not hard to do.

However, even if you accomplish this, if you don't have a good initial guess
for the initial conditions (and for most BVP software, a good initial guess
for the state and adjoint trajectories), the software will not be able to
find a solution.
From: ttj10@eng.cam.ac.uk (Tim Jervis)
Newsgroups: sci.engr.control
Subject: Technical report: real pole balancing
Date: 22 Dec 92 17:35:22 GMT
Organization: Engineering Department, Cambridge University, England.

The following technical report is available via the Cambridge
University ftp archive svr-ftp.eng.cam.ac.uk. Instructions for
retrieval from the archive follow the summary.

------------------------------------------------------------------------------
		 
		 Pole Balancing on a Real Rig using a
		  Reinforcement Learning Controller


		  Timothy Jervis and Frank Fallside


	     Cambridge University Engineering Department
		      Cambridge CB2 1PZ, England



			       Abstract

In 1983, Barto, Sutton and Anderson~\cite{Barto83} published details
of an adaptive controller which learnt to balance a simulated inverted
pendulum. This {\em reinforcement learning} controller balanced the
pendulum as a by-product of avoiding a cost signal delivered to the
controller when the pendulum fell over. This paper describes their
controller learning to balance a real inverted pendulum.  As far as
the authors are aware, this is the first example of a reinforcement
learning controller being applied to a real inverted pendulum learning
in real time.

The results show that the controller was able to improve its
performance as it learnt, and that the task is computationally
tractable. However, the implementation was not straightforward.
Although some of the controller's parameters were tuned automatically
by learning, some were not and had to be carefully set for successful
control. This limits the usefulness of this kind of learning
controller to small problems which are likely to be better controlled
by other means. Before a learning controller can tackle more difficult
problems, a more powerful learning scheme has to be found.

------------------------------------------------------------------------------

			  FTP INSTRUCTIONS

		unix> ftp svr-ftp.eng.cam.ac.uk
		Name: anonymous
		Password: (your_userid@your_site)
		ftp> cd reports
		ftp> binary
		ftp> get jervis_tr115.ps.Z
		ftp> quit
		unix> uncompress jervis_tr115.ps.Z
		unix> 

		If "ftp svr-ftp.eng.cam.ac.uk" does not work,
		you might try "ftp 129.169.24.20".
--
  _/_/_/_/_/  _/  _/      _/   Cambridge University
     _/	     _/  _/_/  _/_/    Engineering Department,
    _/ 	    _/  _/  _/  _/     Trumpington Street,
       	                       Cambridge CB2 1PZ, England
Newsgroups: sci.engr.control
From: kavuri@lips2.ecn.purdue.edu (Surya N Kavuri )
Subject: SVD
Organization: Purdue University Engineering Computer Network
Date: Mon, 28 Dec 1992 20:29:02 GMT


   If I have a transfer function in the Laplace Domain 
 how can I compute SVD ? Are there any algorithms for this ?

  Thanks

  Surya Kavuri


Xref: sparky sci.engr.control:373 alt.control-theory:8
From: rgonzal@gandalf.rutgers.edu (Ralph Gonzalez)
Newsgroups: sci.engr.control,alt.control-theory
Subject: Re: Nonlinear optimal control program available ?
Date: 21 Dec 92 18:36:31 GMT
Followup-To: sci.engr.control
Organization: Rutgers Univ., New Brunswick, N.J.

jwiegand@moe.eng.temple.edu (James Wiegand) writes:

>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.

I'm not an expert in this area, but I think the only general-purpose
approach for nonlinear control systems is the brute-force approach.
That is, you generally can't solve the math analytically (sometimes
it's difficult enough just to formulate it). Therefore you should
apply an adaptive or learning controller to try to optimize your
performance measure empirically, on-line.

In the 60's, King-Sun Fu and others took the approach of partitioning
state space, and "learning" the (sub) optimal control action for
each element of the partition, on-line. The resulting "lookup-table"
allows the controller to select the best control action for each
point in state space. This "brute-force" approach
has the potential for solving any control problem, linear or
nonlinear. The difficulty is that with some systems the partition
must be extremely fine in order to get sufficient accuracy. Also,
since you are trying to learn the best control action within
each partition element, having a fine partition means that your
"training time" becomes large. 

I adapted the lookup table approach in my dissertation, using
a partition which is successively refined to obtain desired
accuracy more quickly and flexibly. I'll be presenting this
approach at the AAAI Spring Symposium on Machine Learning. I'm
hoping it will resurrect the lookup-table approach, in light
of the vastly greater speed and memory available in today's
computers compared with those of the 60's. 

I'd be interested in getting the perspectives of others on this
topic... If anyone's interested in digging up my dissertation (which
I've decided is a bit hard to read!), it was 1989, Univ. of 
Pennsylvania. It also goes into applying this approach hierarchically.

Back to the original question, another brute force approach which
might be useful is artificial neural networks...

-Ralph

-- 
Ralph Gonzalez, Computer Science, Rutgers Univ., Camden, NJ
Phone: (609) 757-6122; Internet: rgonzal@elbereth.rutgers.edu
--
From: jwiegand@moe.eng.temple.edu (James Wiegand)
Newsgroups: sci.engr.control
Subject: Re: Nonlinear optimal control program available ?
Date: 22 Dec 92 22:01:14 GMT
Organization: Temple University EE Dept.

In article <Dec.21.13.36.30.1992.21577@gandalf.rutgers.edu> rgonzal@gandalf.rutgers.edu (Ralph Gonzalez) writes:
>jwiegand@moe.eng.temple.edu (James Wiegand) writes:
>
>>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.
>
>I'm not an expert in this area, but I think the only general-purpose
>approach for nonlinear control systems is the brute-force approach.
>That is, you generally can't solve the math analytically (sometimes
>it's difficult enough just to formulate it). Therefore you should
>apply an adaptive or learning controller to try to optimize your
>performance measure empirically, on-line.
>... If anyone's interested in digging up my dissertation (which
>I've decided is a bit hard to read!), it was 1989, Univ. of 
>Pennsylvania. It also goes into applying this approach hierarchically.
>
>-- 
>Ralph Gonzalez, Computer Science, Rutgers Univ., Camden, NJ
>Phone: (609) 757-6122; Internet: rgonzal@elbereth.rutgers.edu
>--

See? I _knew_ this would happen!
jim
...who learns something new each day.
Newsgroups: sci.engr.control,alt.control-theory
From: acampane@magnus.acs.ohio-state.edu (Angelo Campanella)
Subject: Re: Nonlinear optimal control program available ?
Organization: The Ohio State University
Date: Tue, 22 Dec 1992 20:42:44 GMT



A century or so a fellow by the name of Watts had a nonlinear control problem 
where he was employed to turn a steam valve on and off repeatedly.  Being 
naturally lazy, he invented a leverage sysytem for the machine to do it for 
itself.  He was then credited for inventing the steam engine.  I rather suspect
he went through an evolution process where he needed at times too much memory 
and too much space.   We seem to have compressed those requirments in 
intervening centuries...
Newsgroups: sci.engr
From: rizzo@cbnewsf.cb.att.com (anthony.r.rizzo)
Subject: Re: I don't want to keep looking for new jobs.
Organization: AT&T
Distribution: na
Date: Tue, 29 Dec 1992 02:03:55 GMT

In article <1hd86pINNigi@access.usask.ca> choy@skorpio.usask.ca (I am a terminator.) writes:
>
>Are labor costs too high here. Should we be happy with less? Or are
>the people overseas too tolerant? What's it like to work overseas?

"Too high" is a subjective description.  Costs are higher here
than in many other countries.  People overseas have had much less
for a long time.  So, they are accustomed to much less.  Their cost
of living and their standard of living are lower.  Therefore,
the cost of hiring them is lower.  Therefore, manufacturers
hire them for manufacturing now.  They'll hire them for engineering
tomorrow.

>|> The only way for you and me to maintain our standard of
>|> living is to be able to do things that the overseas types can't do.
>|> Maybe we can get an edge somehow.
>                                      [Rizzo]
>
>Engineers can improve themselves quickly if they have better access to
>good information. Also a procedure for performing engineering work is
>needed.
>I go to the store and see crap on the shelves. The stuff that isn't
>crap is too expensive. I'm accumulating a lot of stuff and it's hard to
>convince me to buy one more thing unless it's really nice. It seems the
>quality of goods must increase exponentially with time to attract buyers.

Yes.  Product quality is important.  American manufacturers are
finally realizing this.  But, frankly, many firms haven't a clue
as to how to DESIGN quality into a product.  Many of them
still use screening tests to select out defective product.
This approach has been shown to be less than ideal, by the Japanese.

>Engineering design quality likely should increase exponentially with
>time. The infrastructure quality has to increase exponentially to permit
>engineering work to increase. For example, I'm working on a clunky
>Dec 5000/120 connected to a 10 Mbit/s Ethernet. The computer is 1 yr
>old, and I want a Dec Alpha connected to fiber. With a 10 Gb hard drive
>and a 30" screen. 100 Mb of RAM. I'm always taking things to the limits.
>If the limits grow, I go faster. I work better. The world becomes a
>better place.

As your management sees it, the world becomes a more expensive
place in which to do business. ;-(

Tony Rizzo (att.com!hogpb!rizzo)