Re: [Vo]:Towel folding robot

[FZNIDARSIC]

 

 
 
Re: [Vo]:Towel folding robot
Harry Veeder
Sat, 10 Apr 2010  11:46:53 -0700

I like the way the robot's torso slides up and down instead of bending.



Harry

.
 
I do too Harry.  I wonder, does that robot come with fringe benefits?
 
Frank

Re: [Vo]:"Clearscan" in Adobe Acrobat 9

[Michel Jullian]

I believe the original images were the same as these (page 18-11 was
missing too, I had to rescan it from my print version):
http://www.scribd.com/doc/13252808/Feynman-Lectures-on-Physics-Volume-3

FYI, there is an annoying bug in AA9, which occurs on some pages of
ClearScan OCRd pdfs when using the text touch up tool, preventing you
to do corrections. It's described here, with a work around:
http://forums.adobe.com/thread/514567
In short, one must use Acrobat 8 (other programs may work too) to do
text touch up on Acrobat 9 produced Clearscan pdfs!

Also, I have found that OCR artifacts are produced on some figures,
sometimes to the extent that the figure is unreadable. That's very
rare (one in several hundred in the Feynman books), but unless one is
prepared to check every image in a large file (and then "declare" the
mangled ones as images on the original file before re_OCRing, I
believe that's possible in Acrobat) maybe it's safer to stick to the
less glamorous but more faithful "searchable image" format for now.

Michel

2010/4/11 Jed Rothwell :
> Michel Jullian wrote:
>>
>> Jed, it seems the way it performs depends on the original document's
>> characteristics (resolution, fonts, multiplicity of fonts maybe?).
>
> Yes. There is remarkable variability between different kinds of documents
> and different versions of Acrobat. I cannot figure out what all of the
> controlling parameters are. It also depends a lot on the number and size of
> the figures, and the amount of noise in the scan (extraneous dots).
>
>>
>> In the case of the Feynman Lectures on Physics, volume 3 (quantum
>> mechanics), of which I made a searchable backup of my print version
>> from an image format pdf found on scribd :
>>
>>
>> 1/ The ClearScan'd pdf file size was several times *smaller* than the
>> original image-only pdf found on the web
>
> What is the URL of that file? I will run it through a variety of different
> Acrobat programs. If ClearScan reduced the size I expect the original was
> made a long time ago with an early version of Acrobat.
>
>>
>> 3/ The OCR quality is much better than what you got with your EPRI
>> document, without any "touching up" I got, for page 1-1 :
>
> That's probably a function of the quality of scan. A good quality scan of
> cleanly printed text without a skew and without much noise will OCR far
> better than an old one like the EPRI document.
> - Jed
>

Re: [Vo]:"Clearscan" in Adobe Acrobat 9

[Jed Rothwell]

Michel Jullian wrote:

Jed, it seems the way it performs depends on the original document's
> characteristics (resolution, fonts, multiplicity of fonts maybe?).


Yes. There is remarkable variability between different kinds of documents
and different versions of Acrobat. I cannot figure out what all of the
controlling parameters are. It also depends a lot on the number and size of
the figures, and the amount of noise in the scan (extraneous dots).



> In the case of the Feynman Lectures on Physics, volume 3 (quantum
> mechanics), of which I made a searchable backup of my print version
> from an image format pdf found on scribd :
>

1/ The ClearScan'd pdf file size was several times *smaller* than the
> original image-only pdf found on the web
>

What is the URL of that file? I will run it through a variety of different
Acrobat programs. If ClearScan reduced the size I expect the original was
made a long time ago with an early version of Acrobat.



> 3/ The OCR quality is much better than what you got with your EPRI
> document, without any "touching up" I got, for page 1-1 :
>

That's probably a function of the quality of scan. A good quality scan of
cleanly printed text without a skew and without much noise will OCR far
better than an old one like the EPRI document.

- Jed

[Vo]:Mpemba Cylinder on its side

[Wm. Scott Smith]

A completely filled curved cylinder on its side would be best, especially if 
the curvature was smaller on one side than the other.

 

A vertical tube shaped like a Force-Free Spiral (google this!) would probably 
be the very best, but very tricky to design and build.

 

Scott
 


From: jone...@pacbell.net
To: vortex-l@eskimo.com
Subject: RE: [Vo]:Scott on Mpemba effect
Date: Sun, 11 Apr 2010 08:32:04 -0700







Pardon the wordy and repetitive prior post… geeze …. one might think I got 
locked out of my car yesterday J
 
There was one point I forgot to make – which might make a good subject for 
further study: the “geometry of the container being used” for freezing and how 
the shape of that container might affect convection, and more particularly the 
“momentum of convection” as it becomes cooler and the active zone becomes 
diminished.
 
My premise is that “convection-inertia” will be maintained at a higher level 
with a geometry that promotes a symmetrical and circular flow. Why? 
 
A form of inertia applicable to convection currents might be rotational inertia 
(moment of inertia), which refers to the fact that a rotating body maintains a 
state of uniform rotational motion. The “body” in this case is not rigid, but 
there is some similarity and analogy.
 
Assuming that conservation of angular momentum is applicable, then – the 
geometry of the freezing container could come into play if it promotes or 
hinders that factor. We might expect the Mpemba effect to be minimal with a 
capillary tube, low with test tube, for instance - but maximized with spherical 
pyrex (labware).
 
Rotational inertia depends on a spin object (“metaphorical” ) and therefore its 
structurally integrity as a rigid body, would come into play - and any geometry 
that diminished that hidden “structure”, would thereby lower the convection 
rate (of the hotter container).
 
 
 
 
From: Jones Beene 
 
Yes, the “continuity” of an established convection rate, which Scott mentions - 
is the only detail not specifically addressed (but it is implied) in  Horace 
Heffner’s fine 10 yr old analysis which is still online at:
 
http://www.mtaonline.net/~hheffner/Mpemba.pdf
 
… and it is a key detail which is quantifiable by analyzing the convection 
currents over time.
 
A key point of Horace’s paper is that it takes as much heat transfer to drop 
~80 deg. C as it does to then freeze 0 deg. C water. 
 
The “heat transfer rate” then is the key to any anomaly – and this rate is 
controlled by convection currents which themselves have momentum.
 
“Momentum” then, or inertia, and its continuity - may be the key to any 
improved understanding… although it is implied in the prior analysis.
 
HH: “Convection currents can dramatically affect heat transfer rates, by 
exposing large volumes of the liquid directly to the heat transfer boundary, be 
that the container walls or the
ice itself. Slow moving molecules are culled out of the moving stream of water 
at the
water-ice boundary. If the water does not move, then the relatively slower 
mechanism of thermal conduction is all that remains to effect the freezing…. If 
the heat transfer rate at 0 deg. C is only doubled by the increased convection, 
then water with an initial temperature of less than about 39.9 deg. C will 
freeze at about the same time as water initially at 0 deg. C. *An almost 40 
deg. advantage is given to the hotter water.*
 
If the convection momentum is greater than doubled, which it probably is – then 
more than 40 degrees can be offset.
 
Jones
 
From: Wm. Scott Smith 
 
I think that water that is warmer than its surrounding will experience greater 
convection; this means that the water is set into a more vigorous motion that 
is sustained even as the temperature difference passes that of the more-still, 
originally colder water.
 
Scott
 
 

Remarkably consistent results. See:

http://arxiv.org/abs/1003.3185

A search for the Mpemba effect: When hot water freezes faster than cold water

James D. Brownridge 


(Submitted on 16 Mar 2010)

Abstract


An explanation for why hot water will sometime freeze more rapidly than cold 
water is offered. Two specimens of water from the same source will often have 
different spontaneous freezing temperatures; that is, the temperature at which 
freezing begins. When both specimens supercool and the spontaneous freezing 
temperature of the hot water is higher than that of the cold water, then the 
hot water will usually freeze first, if all other conditions are equal and 
remain so during cooling. The probability that the hot water will freeze first 
if it has the higher spontaneous freezing temperature will be larger for a 
larger difference in spontaneous freezing temperature. Heating the water may 
lower, raise or not change the spontaneous freezing temperature. The keys to 
observing hot water freezing before cold water are supercooling the water and 
having a significant difference in the spontaneous freezing temperature of the 
two wa

Re: [Vo]:"Clearscan" in Adobe Acrobat 9

[Michel Jullian]

Jed, it seems the way it performs depends on the original document's
characteristics (resolution, fonts, multiplicity of fonts maybe?). In
the case of the Feynman Lectures on Physics, volume 3 (quantum
mechanics), of which I made a searchable backup of my print version
from an image format pdf found on scribd :

1/ The ClearScan'd pdf file size was several times *smaller* than the
original image-only pdf found on the web

2/ Haven't tried printing but it does look better on screen, even
without zooming in

3/ The OCR quality is much better than what you got with your EPRI
document, without any "touching up" I got, for page 1-1 :
<<
1
Quantum Behavior
1-1 Atomic mechanics
"Quantum mechanics" is the description of the behavior of matter and light
in all its details and, in particular, of the happenings on an atomic
scale. Things
on a very small scale behave like nothing that you have any direct experience
about . They do not behave like waves, they do not behave like
particles, they do
not behave like clouds, or billiard balls, or weights on springs, or
like anything
that you have ever seen.
Newton thought that light was made up of particles, but then it was discovered
that it behaves like a wave. Later, however (in the beginning of the twentieth
century), it was found that light did indeed sometimes behave like a particle.
Historically, the electron, for example, was thought to behave like a
particle, and
then it was found that in many respects it behaved like a wave. So it
really behaves
like neither. Now we have given up. We say : "It is like neither. "
There is one lucky break, however-electrons behave just like light. The
quantum behavior of atomic objects (electrons, protons, neutrons, photons, and
so on) is the same for all, they are all "particle waves," or whatever
you want to
call them. So what we learn about the properties of electrons (which
we shall use
for our examples) will apply also to all "particles," including
photons of light.
The gradual accumulation of information about atomic and small-scale behavior
during the first quarter of this century, which gave some indications about
how small things do behave, produced an increasing confusion which was finally
resolved in 1 926 and 1 927 by Schrodinger, Heisenberg, and Born. They finally
obtained a consistent description of the behavior of matter on a small scale. We
take up the main features of that description in this chapter.
Because atomic behavior is so unlike ordinary experience, it is very difficult
to gel used to, and it appears peculiar and mysterious to everyone-both to the
novice and to the experienced physicist. Even the experts do not understand it
the way they would like to, and it is perfectly reasonable that they should not,
because all of direct, human experience and of human intuition applies to large
objects. We know how large objects will act, but things on a small scale just do
not act that way. So we have to learn about them in a sort of abstract
or imaginative
fashion and not by connection with our direct experience.
In this chapter we shall tackle immediately the basic element of the mysterious
behavior in its most strange form . We choose to examine a phenomenon which is
impossible, absolutely impossible, to explain in any classical way,
and which has
in it the heart of quantum mechanics. I n reality, it contains the only mystery.
We cannot make the mystery go away by "explaining" how it works. We will just
tell you how it works. In telling you how it works we will have told
you about the
basic peculiarities of all quantum mechanics.
1-2 An experiment with bullets
To try to understand the quantum behavior of electrons, we shall compare
and contrast their behavior, in a particular experimental setup, with the more
familiar behavior of particles like bullets, and with the behavior of waves like
water waves. We consider first the behavior of bullets in the experimental setup
shown diagrammatically in Fig. 1 - 1 . We have a machine gun that
shoots a stream
of bullets. It is not a very good gun, in that it sprays the bullets
(randomly) over a
fairly large angular spread, as i ndicated i n the figure. I n front
of the gun we have
1-1
1-1 Atomic mechanics
1-2 An experiment with bullets
1-3 An experiment with waves
1-4 An experiment with electrons
1-5 The interference of electron
waves
1-6 Watching the electrons
1-7 First principles of quantum
mechanics
1-8 The uncertainty principle
Note : This chapter is almost exactly
the same as Chapter 37 of Volume I .
>>

I can spot only 4 broken words in the whole page: three "i n" and one
"i ndicated", but why it  makes such silly errors is beyond me, doen't
it use a dictionary?

Michel

2010/4/9 Jed Rothwell :
> I got the latest version of Adobe Acrobat 9 and I am testing this
> "clearscan" OCR option. It looks great in high resolution but unfortunately
> it has some problems:
>
> 1. It makes the files ~3 times bigger.
>
> 2. It does not look any different when printed.
>
> 3. The OCR 

RE: [Vo]:Scott on Mpemba effect

[Jones Beene]

Pardon the wordy and repetitive prior post. geeze .. one might think I got
locked out of my car yesterday :-)

 

There was one point I forgot to make - which might make a good subject for
further study: the "geometry of the container being used" for freezing and
how the shape of that container might affect convection, and more
particularly the "momentum of convection" as it becomes cooler and the
active zone becomes diminished.

 

My premise is that "convection-inertia" will be maintained at a higher level
with a geometry that promotes a symmetrical and circular flow. Why? 

 

A form of inertia applicable to convection currents might be rotational
inertia (moment of inertia), which refers to the fact that a rotating body
maintains a state of uniform rotational motion. The "body" in this case is
not rigid, but there is some similarity and analogy.

 

Assuming that conservation of angular momentum is applicable, then - the
geometry of the freezing container could come into play if it promotes or
hinders that factor. We might expect the Mpemba effect to be minimal with a
capillary tube, low with test tube, for instance - but maximized with
spherical pyrex (labware).

 

Rotational inertia depends on a spin object ("metaphorical" ) and therefore
its structurally integrity as a rigid body, would come into play - and any
geometry that diminished that hidden "structure", would thereby lower the
convection rate (of the hotter container).

 

 

 

 

From: Jones Beene 

 

Yes, the "continuity" of an established convection rate, which Scott
mentions - is the only detail not specifically addressed (but it is implied)
in  Horace Heffner's fine 10 yr old analysis which is still online at:

 

http://www.mtaonline.net/~hheffner/Mpemba.pdf

 

. and it is a key detail which is quantifiable by analyzing the convection
currents over time.

 

A key point of Horace's paper is that it takes as much heat transfer to drop
~80 deg. C as it does to then freeze 0 deg. C water. 

 

The "heat transfer rate" then is the key to any anomaly - and this rate is
controlled by convection currents which themselves have momentum.

 

"Momentum" then, or inertia, and its continuity - may be the key to any
improved understanding. although it is implied in the prior analysis.

 

HH: "Convection currents can dramatically affect heat transfer rates, by
exposing large volumes of the liquid directly to the heat transfer boundary,
be that the container walls or the

ice itself. Slow moving molecules are culled out of the moving stream of
water at the

water-ice boundary. If the water does not move, then the relatively slower
mechanism of thermal conduction is all that remains to effect the freezing..
If the heat transfer rate at 0 deg. C is only doubled by the increased
convection, then water with an initial temperature of less than about 39.9
deg. C will freeze at about the same time as water initially at 0 deg. C.
*An almost 40 deg. advantage is given to the hotter water.*

 

If the convection momentum is greater than doubled, which it probably is -
then more than 40 degrees can be offset.

 

Jones

 

From: Wm. Scott Smith 

 

I think that water that is warmer than its surrounding will experience
greater convection; this means that the water is set into a more vigorous
motion that is sustained even as the temperature difference passes that of
the more-still, originally colder water.
 
Scott
 

 


Remarkably consistent results. See:

http://arxiv.org/abs/1003.3185

A search for the Mpemba effect: When hot water freezes faster than cold
water

James D. Brownridge 


(Submitted on 16 Mar 2010)

Abstract


An explanation for why hot water will sometime freeze more rapidly than cold
water is offered. Two specimens of water from the same source will often
have different spontaneous freezing temperatures; that is, the temperature
at which freezing begins. When both specimens supercool and the spontaneous
freezing temperature of the hot water is higher than that of the cold water,
then the hot water will usually freeze first, if all other conditions are
equal and remain so during cooling. The probability that the hot water will
freeze first if it has the higher spontaneous freezing temperature will be
larger for a larger difference in spontaneous freezing temperature. Heating
the water may lower, raise or not change the spontaneous freezing
temperature. The keys to observing hot water freezing before cold water are
supercooling the water and having a significant difference in the
spontaneous freezing temperature of the two water specimens. We observed hot
water freezing before cold water 28 times in 28 attempts under the
conditions described here.

 

- Jed

 

 

  _  

The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with
Hotmail. Get busy.
 

RE: [Vo]:Scott on Mpemba effect

[Jones Beene]

Yes, the "continuity" of an established convection rate, which Scott
mentions - is the only detail not specifically addressed (but it is implied)
in  Horace Heffner's fine 10 yr old analysis which is still online at:

 

http://www.mtaonline.net/~hheffner/Mpemba.pdf

 

. and it is a key detail which is quantifiable by analyzing the convection
currents over time.

 

A key point of Horace's paper is that it takes as much heat transfer to drop
~80 deg. C as it does to then freeze 0 deg. C water. 

 

The "heat transfer rate" then is the key to any anomaly - and this rate is
controlled by convection currents which themselves have momentum.

 

"Momentum" then, or inertia, and its continuity - may be the key to any
improved understanding. although it is implied in the prior analysis.

 

HH: "Convection currents can dramatically affect heat transfer rates, by
exposing large volumes of the liquid directly to the heat transfer boundary,
be that the container walls or the

ice itself. Slow moving molecules are culled out of the moving stream of
water at the

water-ice boundary. If the water does not move, then the relatively slower
mechanism of thermal conduction is all that remains to effect the freezing..
If the heat transfer rate at 0 deg. C is only doubled by the increased
convection, then water with an initial temperature of less than about 39.9
deg. C will freeze at about the same time as water initially at 0 deg. C.
*An almost 40 deg. advantage is given to the hotter water.*

 

If the convection momentum is greater than doubled, which it probably is -
then more than 40 degrees can be offset.

 

Jones

 

From: Wm. Scott Smith 

 

I think that water that is warmer than its surrounding will experience
greater convection; this means that the water is set into a more vigorous
motion that is sustained even as the temperature difference passes that of
the more-still, originally colder water.
 
Scott
 



 


Remarkably consistent results. See:

http://arxiv.org/abs/1003.3185

A search for the Mpemba effect: When hot water freezes faster than cold
water

James D. Brownridge 


(Submitted on 16 Mar 2010)

Abstract


An explanation for why hot water will sometime freeze more rapidly than cold
water is offered. Two specimens of water from the same source will often
have different spontaneous freezing temperatures; that is, the temperature
at which freezing begins. When both specimens supercool and the spontaneous
freezing temperature of the hot water is higher than that of the cold water,
then the hot water will usually freeze first, if all other conditions are
equal and remain so during cooling. The probability that the hot water will
freeze first if it has the higher spontaneous freezing temperature will be
larger for a larger difference in spontaneous freezing temperature. Heating
the water may lower, raise or not change the spontaneous freezing
temperature. The keys to observing hot water freezing before cold water are
supercooling the water and having a significant difference in the
spontaneous freezing temperature of the two water specimens. We observed hot
water freezing before cold water 28 times in 28 attempts under the
conditions described here.

 

- Jed

 

 

  _  

The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with
Hotmail. Get busy.
 

Re: [Vo]:Towel folding robot

[Stephen A. Lawrence]

On 04/11/2010 09:44 AM, Jed Rothwell wrote:
> Stephen A. Lawrence wrote:
>  
> 
> Second towel took about 22 seconds to fold on camera (chose second towel
> to time for no particular reason).  That's 1/67 the average real time
> per towel, so we can probably conclude that the time lapse rate for the
> video is at least 50 times real time.
> 
> 
> Plus, it says "50 X" on the top left.

  Overlooked that!


> 
> - Jed
> 

Re: [Vo]:Towel folding robot

[Jed Rothwell]

Stephen A. Lawrence wrote:


> Second towel took about 22 seconds to fold on camera (chose second towel
> to time for no particular reason).  That's 1/67 the average real time
> per towel, so we can probably conclude that the time lapse rate for the
> video is at least 50 times real time.
>

Plus, it says "50 X" on the top left.

- Jed

[Vo]:Scott on Mpemba effect

[Wm. Scott Smith]

I think that water that is warmer than its surrounding will experience greater 
convection; this means that the water is set into a more vigorous motion that 
is sustained even as the temperature difference passes that of the more-still, 
originally colder water.

 

Scott

 


 


Date: Sat, 10 Apr 2010 14:23:41 -0400
From: jedrothw...@gmail.com
To: vortex-l@eskimo.com
Subject: [Vo]:New paper on Mpemba effect

Remarkably consistent results. See:

http://arxiv.org/abs/1003.3185

A search for the Mpemba effect: When hot water freezes faster then cold water

James D. Brownridge

(Submitted on 16 Mar 2010)


Abstract

An explanation for why hot water will sometime freeze more rapidly than cold 
water is offered. Two specimens of water from the same source will often have 
different spontaneous freezing temperatures; that is, the temperature at which 
freezing begins. When both specimens supercool and the spontaneous freezing 
temperature of the hot water is higher than that of the cold water, then the 
hot water will usually freeze first, if all other conditions are equal and 
remain so during cooling. The probability that the hot water will freeze first 
if it has the higher spontaneous freezing temperature will be larger for a 
larger difference in spontaneous freezing temperature. Heating the water may 
lower, raise or not change the spontaneous freezing temperature. The keys to 
observing hot water freezing before cold water are supercooling the water and 
having a significant difference in the spontaneous freezing temperature of the 
two water specimens. We observed hot water freezing before cold water 28 times 
in 28 attempts under the conditions described here.


- Jed

  
_
The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with 
Hotmail. 
http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5