HDTenEightyP/NetNews huggingface dataset:
Newsgroups: sci.engr
Subject: Re: Concurrent Engineering Journals, Conferences
From: dlr@testeng.ksc.nasa.gov (Doug Reed)
Date: 18 Nov 92 17:23:51 EST
Organization: Voice Systems Engineering, Kennedy Space Center

In article <1992Nov6.164439.17821@msuinfo.cl.msu.edu> baldwin@pacific.cps.msu.edu (Reid A Baldwin) writes:
>What are the best journals and conference proceedings to look in
>for papers on concurrent engineering?

Send that same question to "vicki@hplvecllvld.hp.com" and she should be
able to email you a list. Tell her I sent ya.

Regards, Doug

-- 
+-----------+---------------------------------+--------------------------+
| Doug Reed | HP3065AT Board Test Engineering | Kennedy Space Center, FL |
+-----------+----+---------------------------++--------------------------+
| Ham Call N4QVY | #include <std_disclaimer> | Lockheed Space Operations |
Xref: sparky sci.engr.control:280 comp.ai.neural-nets:4285
From: sontag@control.rutgers.edu (Eduardo Sontag)
Newsgroups: sci.engr.control,comp.ai.neural-nets
Subject: Re: Fn approxn - ref
Date: 16 Nov 92 19:35:31 GMT
Reply-To: sontag@hilbert.rutgers.edu
Followup-To: sci.engr.control
Organization: Rutgers Univ., New Brunswick, N.J.

In article <1992Nov16.093150.14265@nuscc.nus.sg> elelko@nuscc.nus.sg (Free Man) writes:

   I am looking for a paper by G.Cybenko entitled 'Approximation by
   superpositions of a sigmoidal function'. It's published in Mathematics
   of control, signals and systems (1989), 2. ...

The journal in question is of course "Mathematics of Control, Signals and
Systems," (Springer Verlag, ISSN 0932-4194), which many consider the best
journal in theoretical aspects of Control and Signal Processing (for one
thing, the rejection rate is extremely high, and this helps maintain
standards).  MCSS is entering Volume 6, and currently has a negligible
publication backlog.  If your library doesn't yet subscribe, I suggest that
you simply ask them to.  It is surprising how many times librarians simply
reply "I didn't know anyone here was interested...".

The paper by Cybenko is a 'classic' and the precise reference is as follows:

  Cybenko, G., ``Approximation by Superpositions of a Sigmoidal Function,''
  {\it Math. Control, Signals, and Systems {\bf 2}(1989): 303-314.

  **** SEE ALSO: ``Correction: Approximation by Superpositions of a Sigmoidal
  Function,'' {\it Math. Control, Signals, and Systems {\bf 5}(1992): 455.

Btw, Cybenko's email address is: George.Cybenko@dartmouth.edu
-- 
Eduardo D. Sontag
Department of Mathematics
Rutgers Center for Systems and Control (SYCON)
Rutgers University
New Brunswick, NJ 08903, USA

(Phone: (908)932-3072; FAX: (908)932-5530)
sontag@hilbert.rutgers.edu

*****  def of "algorithm" (due to Fred Landman, Cornell:)
    'An Al Gore rhythm is what Bill Clinton plays on the saxophone'
Newsgroups: sci.engr.control,sci.engr.mech,sci.physics,sci.engr.civil
From: meyers@lorenz.ocean.fsu.edu (Steve Meyers)
Subject: factory noise elimination?!
Organization: Florida State University
Date: Thu, 19 Nov 92 16:02:38 GMT


A company called Andrea Radio or something like that has recently 
announced an ability to reduce or eliminate noise associated with 
industrial production with a technique that "uses electricity". 
I guess their claim is they can make a factory quiet. Has anyone 
heard about this? Is it true? 

I don't read these group regularly, so please e-mail me 
directly.

Thanks in advance.

-Steve
Xref: sparky sci.engr.control:278 alt.industrial.computing:47
From: bencze@isl.stanford.edu (William J. Bencze)
Subject: Simulab -> SystemBuild translation
Organization: Stanford University
Date: 17 Nov 92 13:27:26


Howdy Folks,

  Has anyone built, used, or heard of a translator/filter which
takes Matlab's Simulab system description files and converts them
to Matrix-x's SystemBuild format automatically?  I currently use
Matlab, but would like to use Matrix-x's Autocode function to
generate real-time code which I then can download to their AC100
real-time control box. 

  If anyone has any pointers, hints, or leads on this, please let
me know, either on this group or via e-mail.  Thanks alot, and
keep 'em stable...

-Bill

--
----
 William Bencze                           bencze@isl.stanford.edu
 Department of Electrical Engineering          (415) 497-4210 (H)
 Stanford University                           (415) 723-5176 (O)



Newsgroups: sci.engr.control
From: stote@tomcat.den.mmc.com (M. Stote)
Subject: Re: Simulink problem!
Organization: Martin Marietta Astronautics Group
Date: Tue, 17 Nov 1992 18:30:57 GMT

In article <1e9hpgINNc8j@iskut.ucs.ubc.ca>, lug@balsam.ppc.ubc.ca (Guoqiano Lu) writes:
|> 
|> I am using Simulink to simulate continuous-time self-tuning algorithms. Generally it works well except
|> sometimes there are some crazy peaks in the output which is supposed to be smooth. It seems to me
|> that these are due to the numerical intrgration algorithms that SimuLink used. Any one has the same
|> experiences or any suggestions to overcome this problem? 

I had some similar problems when simulating a system which had both
very fast and very slow dynamics, as well as high levels of noise
and disturbance inputs.  I had to `tune' the integration parameters
of max & min integration step size and integration error tolerance.
I did this heuristically, varying them until I `optimized' simulation
speed and `smoothness'.
   I unfortunately know little about this area and would appreciate
any formalism someone could bring to this topic.

  The fact that you are using a self-tuning algorithm has me a little
suspicious.  Are you sure your peaks in the output are not a result
of the self-tuning algorithm `losing track'  ?  
  Do you see similar peaks in the output if you use a non-adaptive
controller ?  Of course you may not, and it may still be the integration
algorithm having trouble handling the time variation of the tuning
algorithm.

--
Mike Stoughton
stote@den.mmc.com
Newsgroups: sci.engr.control
From: stote@tomcat.den.mmc.com (M. Stote)
Subject: Re: Translating from Xanalog to Simulink
Organization: Martin Marietta Astronautics Group
Date: Mon, 16 Nov 1992 18:54:44 GMT

Simulink does have the capability of using a text-based approach to 
inputting parameters in blocks, even to building block diagrams.

One has to just look at the .m file created by Simulink to get an idea 
of the structure.

Specifically for entering parameters in a block, use the function:
	set_param     ref: Simulink Manual pg 3-32, 4-131

I'm not sure how useful this will be in your translating from Xanalog to
Siimulink, but it is certainly extremely useful in doing parametric
studies.

I whole-heartedly agree with your ocntention on a common structure for blocks
and remember seeing such a structure proposed in one of the CACSD newsletters.

If anyone at Mathworks is reading this group PLEASE listen to this.  Having 
an open interface structure will make it so much easier (ie possible) to 
automate interfaces between various applications
--
Mike Stoughton
stote@den.mmc.com
Newsgroups: sci.engr.control
From: cmkurker@eos.ncsu.edu (CHRISTOPHER M KURKER)
Subject: continuous system identification
Organization: NCSU Project Eos
Date: Wed, 18 Nov 1992 20:55:37 GMT

Hello,

I hope this is an appropriate forum for a question about identification
of continuous-time (CT) and discrete-time (DT) systems.

In my research I need to parameterize a linear system that is the
cascade of a continuous-time system (an anti-aliasing filter with perhaps
two important poles and one important zero) followed by a discrete-time
system (a fourth-order DT Bessel filter).

My goal is to find the overall system's frequency response and various
measures of it, including 3dB frequency, phase linearity, etc.).

I need to parameterize the system from empirical data consisting of
frequency response data from the CT filter and time-domain impulse 
response data from the DT filter.  (I suppose I could get time-domain 
step response data for the CT filter also.) 

I am aware of the various methods
for DT system identification for the DT filter (e.g. method of least
squares), but am unaware of what to do for the CT filter,
short of doing a DFT on the impulse response.  I am also aware
of direct frequency domain IIR DT system design methods which can calculate
a DT transfer function from magnitude and phase vs. frequency data, 
and wonder if an analog of this exists for identifying CT systems.

Any help on this would be greatly appreciated.  Thanks.


Chris Kurker
cmkurker@eos.ncsu.edu
North Carolina State University
Raleigh, NC
From: andrew@rentec.com (Andrew Mullhaupt)
Newsgroups: sci.engr.control
Subject: Re: Solution of matrix Equation AX=XB
Date: 21 Nov 92 23:21:04 GMT
Distribution: na
Organization: Renaissance Technologies Corp., Setauket, NY.

In article <3784@news.cerf.net> heimbold@nic.cerf.net (John Heimbold) writes:
>In article <6611@dciem.dciem.dnd.ca> sjm@dciem.dciem.dnd.ca (Stewart Moorehead) writes:
>> calculated. To calculate X, the equation AX=XB must be solved, with A
>> and B being known 4x4 matrices. I have found two methods which claim to
>> solve for X. 

To start with, a nonsingular solution X to AX=XB means that A=XBX^-1, and
this means that A and B must be similar. X is available by computing the
normal forms of A and B in this case. Computationally, the Shur
triangularization is probably the best. Note that this allows us to consider
the case where A and B are upper triangular without loss...

Now let L be a linear transformation on X defined by 

		L[X] = AX - XB

and notice that if A and B^T have a common eigenvalue, say

		Au = cu,	v^T B = cv^T

then the matrix uv^T is an eigenvector of L with eigenvalue (c - d).

	L[uv^T] = Auv^T - uv^TB = cuv^T - duv^T = (c-d) uv^T.

This means that any common eigenvalue generates a rank one solution,
and any linear combination of these rank one solutions is also a solution.

There will be lots of these, even for A and B which are similar, so it only
makes sense to worry about uniqueness of solutions X of maximal rank. If 
A and B are similar, the maximal rank solution X is unique.

More on this equation can be found in Gantmacher's _Matrix Theory_ and
Horn and Johnson's _Matrix Analysis_.

Later,
Andrew Mullhaupt
Newsgroups: sci.engr.control,sci.engr.civil,sci.engr.control
From: meyers@lorenz.ocean.fsu.edu (Steve Meyers)
Subject: Factory noise elimination2
Organization: Florida State University
Date: Thu, 19 Nov 92 17:06:22 GMT


The name of the company is Andrea Electronic Corp. Anyone 
have an opinion on their new claims.

Steve
Xref: sparky sci.engr.control:305 sci.engr.mech:559 sci.physics:19488 sci.engr.civil:548
From: wang@nyquist.usc.edu (Weizheng Wang)
Newsgroups: sci.engr.control
Subject: Re: Simulink problem!
Date: 18 Nov 1992 06:20:28 -0800
Organization: University of Southern California, Los Angeles, CA
NNTP-Posting-Host: nyquist.usc.edu

In article 289, Guoqiano Lu asked some questions about simulink.
From the description of the problem, I guess that the problem system belong to
one of two cases:
 
(1) The system has fast transient feature, or the system is a bang-bang
control style caused by reseting parameters in self-tuning control.
If the problem is bang-bang control system, the peaks may be the feature
of the system.
(2) The system contains both continuous time and discrete time models.
 
One should not be surprised if some crazy peaks appeared if the "max
step size" in the integration is as large as 10 as default value in simulink
parameters.
 
As pointed out by Mike Stoughton in article 291, some integration
parameters need to be set up before the simulation.
 
As a rule of thumb, one shoul set the "max step size" to be less or equal to
half of minimum sample time among all of discrete time models in the system.
"min step size" should be less or equal to "max step size"/1000.
Generally, a simulation integration algorithm starts the step size from "max
step size", comparing the integration result with a smaller step size. If the
error between these two are smaller than the tolerance value (which is 
resetable by the user in simulink), then the result is accepted. Otherwise, 
take a step size samller than the "smaller step size" in the previous 
computation and compare the result again. The procedure goes on and on until
the minimum step size is reached. Considering the computation procedure, 
setup the parameters before simulation is very important.
 
For a stiff system, gear method or linsim method will be better. However,
the computation is more complex than Euler or Runge-Kutta method. It is a good
idea to switch between different algorithms and compare the results. One can
choose the computation algorithms in the parameter window in simulink.
 
Weizheng Wang
wang@bode.usc.edu
wang@hot.caltech.edu
From: lug@cork.ppc.ubc.ca (Guoqiano Lu)
Newsgroups: sci.engr.control
Subject: Simulink problem!
Date: 18 Nov 1992 22:45:53 GMT
Organization: University of B.C. Pulp & Paper Centre
Distribution: world
NNTP-Posting-Host: cork.ppc.ubc.ca

M. Stote and D. Mattern have advised me to check if the problem is due to "Self-tuning".  It seems
that this is not the case here. Since my friend has found the same problem in simulation of a
  plant  with smooth nonlinearity in open loop. However, it is a good point to switch integration
algorithms. I've tried several algorithms that but did not went through Euler. the problem with Euler is for
larger steps it goes unsteady and for small one it is extremly slow. I will be patient next time. :-)

Newsgroups: sci.engr.control
From: SASPLUND@finabo.abo.fi (Staffan Asplund AT)
Subject: Planning of Experiments
Organization: Abo Akademi University, Finland
Date: Wed, 18 Nov 1992 08:43:49 GMT
X-News-Reader: VMS NEWS 1.23


Crossposted to sci.engr.chem  and sci.engr.control


Hello Engineers,

I tried to ask the mathematicians in sci.math.stat about experimental 
planning, but I did get answers on a *very* theoretical level.

I would like to use a test plan optimized so that the covariance 
between the variables is as low as possible, becouse I have no 
information about the nonlinear modelstructure  that will describe
the system in the best way.  What do You think about that choise?

If the modelstructure is known a good criteria is the D-critera
( Some feedback from Don Ramirez Univ of Virginia:
>The D-optimality criterion is based on the product of the
>eigenvalues of (X'X)**(-1) and is small when only one of these
>eigenvalues are small.
>	A new criterion is based on the mean standard error of a random
>test of u'b; that is the expectation over the unit sphere of a random
>linear inference. This problem has been recently solved by Charles Dunkl
> and Don Ramirez of the University of Virginia and will appear in The
>Transactions of Mathematical Software ACM. 
)


MY QUESTIONS:

1. References or comments on giving low covariance between independent 
   variables in a testplan high priority ?

2. What's Your criteria when planning tests for unknown modelstructures? 



Post or mail, whatever You prefer.
I will summarize Your comments if they are many and 
not posted to the newsgroup.

All comments appreciated,
Staffan

        
 ----------------------------------------------------------------------------
 -               Project researcher / Environmental Engineering             -   
 ----------------------------------------------------------------------------
 -  Staffan Asplund                  -              email sasplund@abo.fi   -
 -  Process Design Lab.              -              phone +358-21-654552    -
 -  Abo Akademi University           -              ph. home  921-882744    -
 -  Finland                          -              fax   +358-21-654791    -
 ---------------------------------------------------------------------------- 


Newsgroups: sci.engr.control
From: mattern@mars.lerc.nasa.gov (Duane Mattern (Sverdrup))
Subject: Re: Simulink problem!
News-Software: VAX/VMS VNEWS 1.41    
Organization: NASA Lewis Research Center
Distribution: usa
Date: 17 Nov 1992 16:57 EDT  

>In article <1e9hpgINNc8j@iskut.ucs.ubc.ca>, 
>lug@balsam.ppc.ubc.ca (Guoqiano Lu) writes:
>I am using Simulink to simulate continuous-time self-tuning algorithms. 
>Generally it works well except sometimes there are some crazy peaks in 
>the output which is supposed to be smooth. It seems to me that these are 
>due to the numerical intrgration algorithms that SimuLink used. Any one 
>has the same experiences or any suggestions to overcome this problem? 

Numerical integration schemes can cause funny problems, particularly when 
used with something like a self-tuning algorithm.  Variable step integration 
schemes in particular tend to "hunt" in an attempt to converge, particularly 
in simulation that include random noise.  But typically they will only run
slowly and not create "peaks".  To check to see if it is the integration 
scheme and not the self-tuning system, switch to a fixed time step 
integration scheme (like Euler), with a small time step.  (I hope that 
you can switch integration schemes in Simulink.  You can do this in ISI's 
SystemBuild, of which I am familiar).  If this clears up the problem, 
then you know its the integration scheme and you can deal with that issue 
by changing your integration technique.

If you still have the "crazy peaks", all that I can suggest (with the 
given information) is to check to make sure that the self-tuning algorithm 
is "sufficiently excited".  Astrom had published some papers in the early 
1980's about the "bursting" phenomen where a self-tuning or adaptive 
scheme can blow up the varying gains if not receiving the proper system 
excitation.  I've experienced this with self-tuning simulation in the 
past.  Typically this might happen in a simulation during steady
state regulation (non-transient), when the characteristics of the 
system build identified or being tuned to, are not available in the
measurements.

Duane Mattern (mattern@mars.lerc.nasa.gov)	(216)433-8186
Sverdrup @ NASA Lewis Research Center, M/S 77-1, 21000 Brookpark Road
Cleveland, OH 44135
Newsgroups: sci.engr.control
From: elelko@nuscc.nus.sg (Free Man)
Subject: Fn approxn - ref
Organization: National University of Singapore
X-Newsreader: Tin 1.1 PL4
Date: Mon, 16 Nov 1992 09:31:50 GMT

[ Article crossposted from comp.ai.neural-nets ]
[ Author was Free Man ]
[ Posted on Mon, 16 Nov 1992 09:29:37 GMT ]


I am looking for a paper by G.Cybenko entitled 'Approximation by
superpositions of a sigmoidal function'. It's published in Mathematics
of control, signals and systems (1989), 2. The stinker is my uni lib
does not have the publication, and neither do the libs within the
region. So the next best thing they have to offer is a lengthy
repographic search request .. 

Can anyone help, like getting in touch with the author thru the internet
?

Rgds,
K.O.Looi
NUS, S'pore
From: lug@balsam.ppc.ubc.ca (Guoqiano Lu)
Newsgroups: sci.engr.control
Subject: Simulink problem!
Date: 17 Nov 1992 01:27:12 GMT
Organization: University of B.C. Pulp & Paper Centre
Distribution: world
NNTP-Posting-Host: balsam.ppc.ubc.ca


I am using Simulink to simulate continuous-time self-tuning algorithms. Generally it works well except
sometimes there are some crazy peaks in the output which is supposed to be smooth. It seems to me
that these are due to the numerical intrgration algorithms that SimuLink used. Any one has the same
experiences or any suggestions to overcome this problem? In addition, are there any
better Simulink-like software available? say, SystamBuild of MatriX?
From: stote@tomcat.den.mmc.com (M. Stote)
Newsgroups: sci.engr.control
Subject: Re: continuous system identification
Date: 20 Nov 92 18:32:14 GMT
Organization: Martin Marietta Astronautics Group

[Question on system id of continuous systems]

since the data you are using to do the identification is discretized
(I assume) the actual sys id is nominally done in the discrete 
domain, although there are can be some advantages in transforming it
out of a direct digital representation into some kind of pseudo-contin.
representation.   I'm not a system id expert so I'll let those more
qualified than I discuss details.

--
Fare Well
				Fear is useless, what is needed is trust!
Mike Stoughton
stote@den.mmc.com
Newsgroups: sci.engr.control,sci.engr.mech,sci.physics,sci.engr.civil
From: boswell@fnalp.fnal.gov (Chris Boswell JHU CDF (708)840-3638)
Subject: Re: factory noise elimination?!
News-Software: VAX/VMS VNEWS 1.4-a4  
Reply-To: boswell@fnalp.fnal.gov
Organization: Fermilab
Distribution:  world
Date: Mon, 23 Nov 1992 03:15:53 GMT

meyers@lorenz.ocean.fsu.edu (Steve Meyers) writes...
>announced an ability to reduce or eliminate noise associated with 
>industrial production with a technique that "uses electricity". 
>I guess their claim is they can make a factory quiet. Has anyone 
>heard about this? Is it true? 
	Yes, this is true.  Sound waves are waves, and
can be interfered with, both constructively and destructively.
If I have a speaker system such that sound waves are exactly
out of phase with the factory motor, the sound waves are cancelled.
You can either do this right in front of your ear, or on a surface
around the noisy motor.  To do it well with today's audio technology,
the motor has to have a very periodic sound signature,
which most motors do.
  I am afraid I cannot find the articles I have about it,
but search the periodical guide in a library for
active noise elimination or electronic mufflers.
Newsgroups: sci.engr.control