HDTenEightyP/NetNews huggingface dataset:
From: nroddier@noao.edu (Nicolas Roddier)
Subject: Global stabilty dependent on constant input?
Organization: National Optical Astronomy Observatories, Tucson, AZ, USA
Date: Wed, 30 Sep 1992 18:54:18 GMT


Hello control people!

I'm wondering if the global asymptoticaly stability of a system can depend
on a constant input.

In other word, I have the system Xdot = f(x), f(0)=0 that is globally
assympotically stable around the origin. Now, what can I say about the
system Xdot = f(x) + C, where C is a constant vector. I would tend
to think that the equilibrium shifts from the origin to another location
but still has an infinitely large bassin of attraction, this true for
linear system. How does it sound when f() is nonlinear?

I'd appreciate any refence and comments/ideas. Thank you.

Nick Roddier

----------------
nroddier@noao.edu
----------------


Newsgroups: sci.engr.control
From: jpensar@bode.abo.fi (Johan Pensar RT)
Subject: Re: Query on the use of software packages in control engineering
Organization: Abo Akademi University, Finland
	<29SEP199207505013@lims01.lerc.nasa.gov>
Date: Wed, 30 Sep 1992 09:17:41 GMT

In article <29SEP199207505013@lims01.lerc.nasa.gov> focstea@lims01.lerc.nasa.gov (CHRISTOPHER STEARNS) writes:
   Just a clarification, but I believe the Mathwork's simulation package that 
   is integrated with Matlab is called Simulab.

In v. 1.2 the name has changed to SimuLink, perhaps a trademark problem?

Johan,
-----------------------------------------------------------------------
Johan Pensar                                E-mail: jpensar@aton.abo.fi
Process Control Laboratory                  Phone:  +358 21 654743
Abo Akademi University                      Home:   +358 21 542535
Biskopsgatan 8                              Fax:    +358 21 654479  
SF-20500 Abo, Finland                       Room:   366 (Axelia)
-----------------------------------------------------------------------




--
-----------------------------------------------------------------------
Johan Pensar                                E-mail: jpensar@aton.abo.fi
Process Control Laboratory                  Phone:  +358 21 654743
Abo Akademi University                      Home:   +358 21 542535
Biskopsgatan 8                              Fax:    +358 21 654479  
SF-20500 Abo, Finland                       Room:   366 (Axelia)
-----------------------------------------------------------------------
           "Strong typing is for people with weak memories"

Newsgroups: sci.engr.control
From: teek@kingcong.UWaterloo.ca (Prateek Dwivedi)
Subject: database managers 
Organization: University of Waterloo
Date: Tue, 29 Sep 1992 20:18:34 GMT

Just wondering if anyone can recommend a database management system that is
suitable for a CACSD environment. We are implementing on a Unix box.
(anything you have heard or have implemented)

Anyone have any luck with version control software?


Thanks,

Teek (Prateek Dwivedi)                  teek@kingcong.uwaterloo.ca
Research Assistant                      pdwivedi@systems.watstar.uwaterloo.ca
Flight Control Systems Group            (519)885-1211 x5314     Voice
University of Waterloo, Canada          (519)746-3077           Fax
-- 
Teek (Prateek Dwivedi)			teek@kingcong.uwaterloo.ca
Research Assistant			pdwivedi@systems.watstar.uwaterloo.ca
Flight Control Systems Group		(519)885-1211 x5314	Voice
University of Waterloo, Canada		(519)746-3077  		Fax
From: Bob.Clarke%bbs@actcnews.res.utc.com (Bob Clarke)
Newsgroups: sci.engr
Subject: No Clean Solder Flux
Date: 2 Oct 92 15:54:15 GMT
Organization: United Technologies Research Center
X-Posting-Software: UnixBBS 1.02a S/N 190921

Anyone using No Clean Solder Flux in a wave solder process for the
Aerospace industry?  If you tried it and now don't use it, why?  If you
are about to try it or currently do use it would you like to open a
dialog?
--
Bob Clarke, user of the UnixBBS System @ actcnews.res.utc.com
E-Mail: Bob.Clarke%bbs@actcnews.res.utc.com
========================================================================
   United Technologies Corporation
   Opinions expressed do not necessarily represent UTC.
From: zaval@athena.mit.edu (Antonis)
Subject: Ringless Piston
Organization: Massachusetts Institute of Technology
Date: Thu, 1 Oct 1992 14:26:07 GMT

  I am looking for a ringless (no O-rings) hydraulic piston with
  a diameter of 1"-2" (25-50mm) to be used at pressures of the order of
  50-150 bar. Anybody knows a (US prefferably) source.

  I would appreciate  personal e-mail answers to 
  zaval@duvm.ocs.drexel.edu

  Thanks,

  Antonis Zavaliangos
From: arthur@ccwf.cc.utexas.edu (Arthur X. Nghiem)
Newsgroups: sci.engr
Subject: Undergraduate looking for advise for design project
Date: 27 Sep 92 20:22:06 GMT
Reply-To: arthur@ccwf.cc.utexas.edu (Arthur X. Nghiem)
Organization: The University of Texas at Austin, Austin TX
Originator: arthur@sleepy.cc.utexas.edu


	I am an Undergraduate student in the Electrical Eng. College of the 
University of Texas at Austin.  Although I am more interested in the higher
level Computer Engineering aspects, I am currently studying analog circuits 
in our 2nd year EE Lab.
	Some advise on how to make the most of this course would be highly
appreciated.  Specifically, I have some flexibility as to what my partner and
I will build for our design project.  I would like to build something that
hasn't been done repeatedly.
	The types of projects that are listed in our Lab Material are devices
such as wireless FM microphones, electronic thermometers, and voice scrambler/
descramblers.  All of which have been built previously (ad nauseum).
	A project that I've been thinking about is to built an optoelectronic
device that can sense vibrations off of glass.  I don't know enough about 
optoelectronics to know how feasible it is to construct a laser (or other) 
sensor that can respond to these vibrations.
	If anyone reading this posting has any comments on how a laser might 
be used in this sense or has any suggestions on other projects I might consider
please send me Electronic Mail:
				arthur@ccwf.cc.utexas.edu

	Also, I am working on a report on Oscillators (and the piezoelectric 
effect).  If anyone reading this posting knows of any recent developments
regarding Oscillators or the piezoelectric effect, PLEASE tell me.  
Additionally, recommendations of good sources of information on these topic 
would be very much appreciated.


	Thank you,
	Arthur X. Nghiem
-- 
|  (|/ '()` <()/    ________________________________________________  
 _ O        .> |   / Arthur X. Nghiem  arthur@ccwf.cc.utexas.edu
  /_/  -__ -- /    \                   PO Box 7103-Austin, Tx 78713  
          ---
From: acampane@magnus.acs.ohio-state.edu (Angelo Campanella)
Subject: Re: FFT,  and  - to find shedding frequency
Summary:   Vortex Shedding Measurement.
Organization: The Ohio State University
Date: Wed, 30 Sep 1992 02:59:53 GMT

I've just recently obtained a Larson-Davis 2900 Sound level and vibration 
analyzer (about $9,000), which analyses analog signals down to 0.8 Hz.
It will do FFT, but More importantly, it does 1/3 octave band analysis with
digital filtering. This will side-step all your instrument development woes, in 
my opinion.

I've just used mine to measure vibrations in the few Hz to few dozen Hz region.

Filter settling time is about one minute, but when it settles, you have a
measurement accurate to a tenth of a decibel (1% amplitude ) for each band.

Hopes of seeing neat narrowband signals are usually dulled by reality.

When looking at community noise which included cricket chirps, I thought the
FFT would show them as a few lines, but lo and behold, they smeared over many
lines.  I guess the crickets were  FM'ing a little (or 'chirping' as in sonar 
parlance!).

The beauty of the 1/3 octave bands is that down in the few Hz region, most
off-the-shelf FFT analyzers fall flat on their face.  Typically, 400-line FFT
analyzers working across a 1,000 Hz band has filters that are 2.5 Hz wide (ALL
of them).  Down in your shedding frequency area, that's a whopping big chunk of
your working spectrum to average across.

On the other hand, the 1/3 octave filters are centered at the ISO frequencies
of 0.8, 1.0, 1.2, 1.6, 2, 2.5, 3.1, 4, 5, 6.3, 8, 10 Hz, etc.. giving handy
resolution where you need it most.

The LD 2800 (1 channel version) is off the shelf.  Larson-Davis is located in
Provo, Utah (801)-375-0177, FAX=375-0182, Ask for Derek Anderson. Tell him I
recommended this to you.

These units have a high impedance input, so that the hot wire anemometer should
work OK.  If the ac signal therefrom is feeble, you may need a preamp..., but
try it straight-in first..

                                     Ang. Campanella.
Xref: sparky sci.engr:2090 sci.math:12627
From: dsimon@atlas.nafb.trw.com
Newsgroups: sci.engr,sci.math
Subject: Sampled White Gaussian Noise
Date: 2 Oct 92 09:06:16 PST

The variance of sampled noise increases with the sampling frequency!

Mathematically it is not so difficult to understand, but I can't
understand it intuitively.  Why would the variance change with the
sampling frequency?

Consider a gaussian white noise process with 2-sided PSD N/2.
Then if we take samples of the noise with sampling frequency f,
the variance of each sample is Nf/2.  Can anyone expain this intuitively?
---------
Dan Simon
From: flip@tbd2.brl.mil (Philip J. Peregino )
Newsgroups: sci.engr
Subject: Re: the pitot tube
Date: 1 Oct 92 17:53:54 GMT
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.

In article <1992Sep28.150828.1@kean.ucs.mun.ca> bway@kean.ucs.mun.ca writes:
>Can anybody tell me what a "pitot tube" is? As well, where would be a 
>good place to find information (eg. a journal article) about it. 
>Thanx.  Brent

A pitot tube is a probe used to measure the stagnation pressure in a fluid
flow.  The probe is typically a hollow tube and commerical pitot tubes come
as small as 1.5mm in diameter and the tube faces directly upstream.  A
common application of this is on a power boat, a pitot tube is mounted on
the stern of the boat and it is connected to a speedometer.

More detailed information can be found in any fluids books.
Newsgroups: sci.engr,sci.math.num-analysis,sci.engr.mech,sci.comp-aided
From: jkdickin@yoho.uwaterloo.ca (John K. Dickinson)
Subject: I am in need of some tetrahedralized objects
Keywords: Finite Element Analysis
Organization: University of Waterloo
Date: Thu, 1 Oct 1992 17:11:20 GMT

	I am working on a iterative technique matrix solver for large
sparse matrices generated by finite element analysis of solids.
The actual solver is completed but I need some "real" data to test.
The data I need is 3-d objects tetrahedralized using from 1000-3000 nodes
and some sort of description of it's surface.

	If anyone has a file containing a list of x,y,z co-ords. for the nodes
and then a list of nodes in each terahedron that they could send me I'd greatly
appreciate it. My code can then generate the FEM matrix to be solved. If you
also provide some boundry conditions for the shape then I can even try to
produce results true to the problem.

	These test cases will appear in a Master's thesis and perhaps in a
paper or two. Credit for their origin can be given in these documents.

	Thanks for reading this. John

Xref: sparky sci.engr.civil:467 sci.research:1128 sci.geo.geology:2039
Organization: Middle East Technical University - Computer Center
Date: Thursday, 1 Oct 1992 13:10:38 TUR
From: <C44590@TRMETU.BITNET>
Newsgroups: sci.engr.civil,sci.research,sci.geo.geology
Subject: 3D stress analysis in crack problems

i am looking for sources having information on three dimensional displcement
discontiniuities stress analysis for crack problems and computer programms
written on this subjects.
Also,I need help on the subject of three dimensional stress analysis of crack
tip elements.
with highest regards.



P.S:please send personal e-mail.
Newsgroups: sci.engr.civil
From: yousif@enel.ucalgary.ca (Abdel-Fattah S. Yousif)
Subject: The GPS/INS and CCD camera Synch. problem!!
Date: Mon, 28 Sep 92 19:47:49 GMT
Organization: ECE Department, U. of Calgary, Calgary, Alberta, Canada

Hi Everybody,

	I am posting this message for a friend of mine. He is in Geomatics
Eng. Dept., the U. of Calgary. I am not sure if this news group is the most
appropriate to post this message but couldn't find any other. Please 
respond to yousif@enel.ucalgary.ca.  

---CUT HERE---------------------------------------------------------------
Hi
	I am a graduate student at the U. of Calgary doing a Ph.D in the 
integration of the Global Positioning System and the Inertial Navigation System
(GPS/INS). We are using a CCD push broom camera mounted on an aircraft for
collecting pictures during experiments. 

	I would like to know if anybody is working in this field. If so,
is there a known solution for the time synchronization problem of this
system? The CCD camera takes pictures contineously and we need to relate
the pictures (in the time domain) with signals recieved from the satellite.
Any suggestions, new ideas, or references will be appreciated. I would also
be interested in FTP sites where I can get software programs also related
to the subject. I will summarize to the group if enough responses are
recieved. Thank you in advance for your help.

Yours, 
Naser El-Sheimy

Newsgroups: sci.engr.civil
From: jlb@thor.inesc.pt (Jose' Luis B. Borbinha)
Subject: HELP: Intelligent Buildings
Organization: INESC - Inst. Eng. Sistemas e Computadores, LISBOA. PORTUGAL.
Date: Thu, 1 Oct 1992 09:31:22 GMT

  Hi,

 I'm a PhD student at the Lisbon Technical University, from where I've also
a graduate and a master degree in Computers.

 I'm working now in the integration of services in "inteligent buildings"
(residential buildings, offices, etc). The target is the total integration of
services usually treated as separeted ones, like "automation services"
(energy and air conditionned management, access and fire security, elevators
control, etc), communication networks (phones, fax, etc) and computer
services (computer networks with CPUs, printers, file servers, etc).

 Therefore, and with the purpose of the exchanging of ideias, I'm looking for
people interested in this subject, comming not only from the computer/electrical
area but also from another ones (like architecture, civil eng., etc),

thank you,

-- 
 Jose' Luis B. Borbinha | INESC - Inst. de Eng. de Sistemas e Computadores
  E-mail: jlb@inesc.pt  |         Rua Alves Redol, 9
  Phone:  351.1.3100305 |         Apartado 10105
  Fax:    351.1.525843  |         1017 Lisboa CODEX - PORTUGAL
Newsgroups: sci.engr.civil
From: gregk@longs.LANCE.ColoState.Edu (Gregory Krueger)
Newsgroups: sci.engr.civil
Subject: Septic tanks, and tile fields
Date: 6 Oct 92 05:16:02 GMT
Organization: Colorado State U. Engineering College

Hello,
	As a senior in Civil Engineering, we are required to take a 
class in Wastewater Treatment and Design.  Our first design problem
was a simple septic tank.  We have been required to go to the library
to obtain information.  Unfortunately there are 90 of us, and the first
three or so over there checked everything out.  I was able to find some
light information in the reference section, but not enough to base any sort
of design on.  I was wondering if anyone had any information on any
magazines or government documents where this information could be located.
It's very much appreciated.  Thanks.


Gregory D. Krueger


p.s.  He probably should have done his lecture on Ethics in Engineering
 	before the assignment!  :-)
Newsgroups: sci.engr.civil
From: olmstead@sail.uwaterloo.ca ()
Subject: GPS Surveying
Originator: olmstead@sail.uwaterloo.ca
Organization: University of Waterloo
Date: Mon, 28 Sep 1992 18:59:44 GMT

Hello

Has anyone considered the use of GPS for use on microwave path surveys?

Are there any GPS experts I can e-mail questions to regarding.  This is
for a fourth year civil engineering project and any help would be
appreciatted.

Thanks

Mike Olmstead
olmstead@sail.uwaterloo.ca
fmolmstead@civil.watstar.uwaterloo.ca

Newsgroups: sci.engr.civil
From: sprent@sol.surv.utas.edu.au (Tony Sprent)
Subject: Re: GPS Surveying
Organization: University of Tasmania
Date: Fri, 2 Oct 1992 04:41:18 GMT

In article <BvAy3L.2IJ@watserv1.uwaterloo.ca>, olmstead@sail.uwaterloo.ca () writes:
> 
> Hello
> 
> Has anyone considered the use of GPS for use on microwave path surveys?
> 
> Are there any GPS experts I can e-mail questions to regarding.  This is
> for a fourth year civil engineering project and any help would be
> appreciated.
> 
> Thanks
> 
> Mike Olmstead
> olmstead@sail.uwaterloo.ca
> fmolmstead@civil.watstar.uwaterloo.ca


I have been wondering for some time whether there is a newsgroup which covers
GPS and its applications and have asked a few colleagues if they knew of one 
without success.

By chance I happened to look in sci.engr.civil and noticed there were a couple 
of postings on the subject. Can anyone tell me if such a group exists and if
not, whether it would be worthwhile having one.
________________________________________________________ 
Tony Sprent
Department of Surveying and Spatial Information Science
University of Tasmania
GPO Box 252C Hobart
Tasmania

Phone 61-02-202110 Fax 61-02-202110  International    
        002-202110       002-240282  Australia
email   sprent@surv.utas.edu.au
________________________________________________________
Newsgroups: sci.engr
From: rizzo@cbnewsf.cb.att.com (anthony.r.rizzo)
Subject: Re: Fate of the Energetic Teacher
Organization: AT&T
Distribution: na
Date: Mon, 5 Oct 1992 13:44:45 GMT

In article <1992Oct04.000328.1546@jlc.mv.com> john@jlc.mv.com (John Leslie) writes:
>In article <1992Oct2.143330.24239@cbfsb.cb.att.com> (anthony.r.rizzo) writes:
>>
>> Government and the educational system could learn much from the
>> "Process Quality Management and Improvement" programs that are
>> being implemented in the private sector.
>>
>> As I see it, the students are the customers, and the educational
>> system is the supplier.
>
>   Customers are people who buy something.  There is a well-established
>industry of greeting cards.  All the firms in this business know that
>their customer is the buyer of the card, not the recipient.  Why do
>educators insist on believing that _their_ customers are the recipients,
>not the buyers?
>
>> Yes, I know that this is not alt.politics.  But the deterioration
>> of the school system inevitably will lead to the deterioration
>> of industrial competitiveness.  It will affect even my own
>> children's ability to earn a living, even though they are only
>> 4 year old and 15 months old right now.
>
>   Now you sound like a customer.  Quality Improvement programs _do_
>have a lot to offer us, once we've correctly identified the customer.
>Customers can learn to recognize and value quality, once the supplier
>takes the time to listen to their needs and adjust the specifications
>to fit those needs.
>
>   Could we re-cast this discussion, starting with the customers' needs
>and progressing into adjusting the specifications?

Sure!
I will very soon become a customer of the school system in the country.
In fact, I am already a customer, in one sense.

My near-term needs are these:

1)  My children need to learn the basic skills that are essential
    to continued learning.

2)  My chilren need a physically and emotionally safe and nurturing 
    environment where they can acquire those skills.

My longer-term needs are these:

3)  My children will need to prepare for one of two career paths, either
    employment without a college education or employment with a college
    education.  Therefore, I need the 9-12 segment of the school system
    to prepare them adequately for either of those career choices.

4)  I and my children will need continued education in select areas
    of knowledge, throughout our lives.

5)  I and my children will need retraining, at some point in our careers.

Now that you know the customer's needs, lets see the specifications.


Tony Rizzo

Newsgroups: sci.engr
From: murat@volcan.kamchatka.su (Zhuravlev Murat )
Subject: Astringment substance without clinker for building purposes.
Keywords: building
Reply-To: murat@volcan.kamchatka.su
Organization: Institute of Volcanology (Kamchatka)
Date: Mon, 28 Sep 92 16:49:07 -0400

Dear sirs,
  Let me suggest to your attention little advertising information.
We'll very pleasant for your notes and any related information.
E-mail address: murat@volcan.kamchatka.su


   ASTRINGENT SUBSTANCE WITHOUT CLINKER FOR BUILDING PURPOSES

Possible substitute of portland cement is suggested.
The method of getting astringent substance without clinker on the
basis of silicate & alumosilicate rocks is worked out.

ASTRINGENT SUBSTANCE'S COMPOSITION:

Silicate or alumosilicate rock             72.5 - 90%
Composition correcting additive             8.0 - 15%
Activating additive                         3.0 - 13%
Other additives: plastificator,
air-involver etc.                           up to 1.0%

ASTRINGENT SUBSTANCE'S MAIN CHARACTERISTICS:

Specific surface                           200 - 500 m/kg
Pour density                                 0.9 - 1.1 g/cub.sm
Water/astringent substance ratio              0.4 - 0.55
Activity                                   up to 40 - 50 MPa
Time needed for 75% firmness gain
under steaming                             6 - 12 hours
Thermoresistance                           1000 - 1200C
Frost-resistance                           not less than 50 cycles

  Technology of astringent substance's witout clinker production
consists of dispergation of the initial silicate or alumosilicate
rock with correcting additive  up to 200 - 500 m/kg  specific
surface. The value of 250 - 350 m/kg for the specific surface
are more good. Other additives ( activating etc. ) are added with
water.
  Concrete mixture production, wares' moulding, thermo-humid pro-
cessing are utterly entered the technological scheme of the co-
rresponding productions on the basis of ordinary cements.
  The concretes on the basis of astringent substance without
clinker are needed less amounts of the astringent substance than
ordinary cements with the affinity of physico-chemical properties
of the astringent substance's basis & inert fillers.

  The group of elaborators of the astringent substance without
clinker is ready to conclude the agreement on the:
- exploration of the customer's raw material & possibility of
  its utilization as the astringent substance's basis;
- elaboration of the astringent substance's composition on the
  basis of customer's raw material;
- determination of the astringent substance's physico-chemical
  properties & conditions of the thermo-humid processing;
- elaboration of the concrete's mixture composition for blocks
  & bricks production;
- if it's necessary - to accomplish production of the experimental
  lot of blocks & bricks on the basis of customer's raw material
  & equipment.
From: csc@coast.ucsd.edu (Charles Coughran)
Newsgroups: sci.engr
Subject: Re: the pitot tube
Date: 28 Sep 1992 23:39:46 GMT
Organization: Center for Coastal Studies, SIO
Reply-To: csc@coast.ucsd.edu.UCSD.EDU (Charles Coughran)
NNTP-Posting-Host: coast.ucsd.edu


In article <1992Sep28.150828.1@kean.ucs.mun.ca> bway@kean.ucs.mun.ca writes:
>Can anybody tell me what a "pitot tube" is? As well, where would be a 
>good place to find information (eg. a journal article) about it. 
>Thanx.  Brent

A Pitot tube is a differential pressure based flowmeter.  Pressure taps
are arranged in a thin tubular probe so as to measure static pressure
and impact (or stagnation) pressure.  Their difference is proportional
to the square root of velocity.  They are simple, cheap, and have
been around since 17 hundred and something.  For a discussion of
their uses and limitations see any introductory fluid mechanics
text or flow measurement handbook.


-- 
         Practice Random Kindness And Senseless Acts of Beauty.
ccoughran@ucsd.edu (Internet) ...!ucsd!ccoughran (UUCP) CCOUGHRA@UCSD (BITNET)