Driver to drive?

On Thu, 19 Nov 2009 12:04:50 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Thu, 19 Nov 2009 11:24:19 -0500, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Jan Panteltje wrote:
On a sunny day (Thu, 19 Nov 2009 03:43:15 -0500) it happened Yousuf Khan
bbbl67@yahoo.com> wrote in<4b050521$1@news.bnb-lp.com>:

They are theorizing that using these quantum dots, that they can recover
close to 90% of Carnot efficiency!

Yousuf Khan

Harnessing waste heat from laptop computers, cell phones may double
battery time
"Theory says that such energy conversion can never exceed a specific
value called the Carnot Limit, based on a 19th-century formula for
determining the maximum efficiency that any device can achieve in
converting heat into work. But current commercial thermoelectric devices
only achieve about one-tenth of that limit, Hagelstein says. In
experiments involving a different new technology, thermal diodes,
Hagelstein worked with Yan Kucherov, now a consultant for the Naval
Research Laboratory, and coworkers to demonstrate efficiency as high as
40 percent of the Carnot Limit. Moreover, the calculations show that
this new kind of system could ultimately reach as much as 90 percent of
that ceiling."
http://www.sciencedaily.com/releases/2009/11/091118101403.htm


Of course the Carnot limit is (1-Tcold/Thot), where Thot is the absolute
(Kelvin) temperature of the hot reservoir (e.g. the boiler in a steam
engine) and Tcold is that of the cold reservoir (the heat sink).

So if your computer is running at 50C and dumping heat at 30C (due to
the heat sink's inefficiency), the Carnot limit is 1-303K/323K = 6%.

Good luck doubling battery life with that.

Cheers

Phil Hobbs

You forgot the Obama multiplier ;-)

Is that the same as dividing by Slowman's IQ?
Click to expand...
 
"krw" <krw@att.bizzzzzzzzzzz> wrote in message
news:j37cg5l9tn7e73ge5qf6hqq29p8av25o8s@4ax.com...
You forgot the Obama multiplier ;-)

Is that the same as dividing by Slowman's IQ?
Click to expand...
No, only God can divide by zero.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms
 
John Larkin wrote:

The coolest current transformer is a second-harmonic DCCT, accurate to
parts-per-million from DC to many kilohertz.
Click to expand...
Enquiring minds etc :). I thought at first that sounded like a
variation on the old fluxgate compass idea from ww2 and earlier, where
the earth's magnetic field varies the saturation of a toroidal ring and
the second harmonic amplitude recovered in 3 levels in 120 degree
segments, but it's quite different. Here's a good article on the principle:

cdsweb.cern.ch/record/1183400/files/CERN-BE-2009-019.pdf

Page 3 of 4 for the block diagram.

Using a feedback loop to cancel the induced magnetic field. Very neat.

Something new to learn in electronics every day :)...

Regards,

Chris
 
ChrisQ wrote:

cdsweb.cern.ch/record/1183400/files/CERN-BE-2009-019.pdf

Page 3 of 4 for the block diagram.

Using a feedback loop to cancel the induced magnetic field. Very neat.
Click to expand...
The above last line is rubbish.

Engage brain and analyse the schematic properly before posting :-( !. In
fact, it is the second harmonic that is detected...

Regards,

Chris
 
On Fri, 20 Nov 2009 12:54:00 +0000, ChrisQ <meru@devnull.com> wrote:

John Larkin wrote:


The coolest current transformer is a second-harmonic DCCT, accurate to
parts-per-million from DC to many kilohertz.


Enquiring minds etc :). I thought at first that sounded like a
variation on the old fluxgate compass idea from ww2 and earlier, where
the earth's magnetic field varies the saturation of a toroidal ring and
the second harmonic amplitude recovered in 3 levels in 120 degree
segments, but it's quite different. Here's a good article on the principle:
Click to expand...
The DCCT essentially uses a fluxgate - two of them, usually - to
detect the cancellation of two currents, one the customer's current
and the other a local feedback current. The null detection can be
insanely sensitive, just as a fluxgate compass is insanely sensitive.

John
 
On Thu, 19 Nov 2009 11:14:13 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Thu, 19 Nov 2009 03:43:15 -0500) it happened Yousuf Khan
bbbl67@yahoo.com> wrote in <4b050521$1@news.bnb-lp.com>:

They are theorizing that using these quantum dots, that they can recover
close to 90% of Carnot efficiency!

Yousuf Khan

Harnessing waste heat from laptop computers, cell phones may double
battery time
"Theory says that such energy conversion can never exceed a specific
value called the Carnot Limit, based on a 19th-century formula for
determining the maximum efficiency that any device can achieve in
converting heat into work. But current commercial thermoelectric devices
only achieve about one-tenth of that limit, Hagelstein says. In
experiments involving a different new technology, thermal diodes,
Hagelstein worked with Yan Kucherov, now a consultant for the Naval
Research Laboratory, and coworkers to demonstrate efficiency as high as
40 percent of the Carnot Limit. Moreover, the calculations show that
this new kind of system could ultimately reach as much as 90 percent of
that ceiling."
http://www.sciencedaily.com/releases/2009/11/091118101403.htm
Click to expand...
If it were as efficient as claimed, there would be no point in using
it as a waste recovery method - it would be used as or within the
primary converter to prevent escape of losses.

RL
 
nuny@bid.nes wrote:
On Nov 19, 12:15 pm, Phil Hobbs
pcdhSpamMeSensel...@electrooptical.net> wrote:
n...@bid.nes wrote:
On Nov 19, 3:14 am, Jan Panteltje<pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Thu, 19 Nov 2009 03:43:15 -0500) it happened Yousuf Khan
bbb...@yahoo.com> wrote in<4b05052...@news.bnb-lp.com>:

They are theorizing that using these quantum dots, that they can recover
close to 90% of Carnot efficiency!

As Phil Hobbs points out, the Carnot max at reasonable temperatures
is a screaming 6%, so they're bragging they can recover nearly 5.4%?

BFD.

...a different new technology, thermal diodes...

Sorry, not gonna happen. Rectifying thermal energy can be better
modeled with microphones. Microphones only work because the sensing
element vibrates out of phase with a static element (the frame). Heat
jiggles both of them, randomly in and out of phase. Other power input
is required to damp the in-phase part (like running a Peltier junction
backwards). Otherwise, no net power. Period.

Mark L. Fergerson

There are energy scavenging techniques that can run off an ambient
temperature gradient, e.g. across an article of clothing. You don't get
much power, but even a few tens of microwatts would be interesting for
some purposes.

They require an energy differential, yes?


Mark L. Fergerson
Click to expand...
Yes, they work off gradients, like hydroelectric dams. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net
 
On Nov 19, 12:15 pm, Phil Hobbs
<pcdhSpamMeSensel...@electrooptical.net> wrote:
n...@bid.nes wrote:
On Nov 19, 3:14 am, Jan Panteltje<pNaonStpealm...@yahoo.com>  wrote:
On a sunny day (Thu, 19 Nov 2009 03:43:15 -0500) it happened Yousuf Khan
bbb...@yahoo.com>  wrote in<4b05052...@news.bnb-lp.com>:

They are theorizing that using these quantum dots, that they can recover
close to 90% of Carnot efficiency!

   As Phil Hobbs points out, the Carnot max at reasonable temperatures
is a screaming 6%, so they're bragging they can recover nearly 5.4%?

   BFD.

...a different new technology, thermal diodes...

   Sorry, not gonna happen. Rectifying thermal energy can be better
modeled with microphones. Microphones only work because the sensing
element vibrates out of phase with a static element (the frame). Heat
jiggles both of them, randomly in and out of phase. Other power input
is required to damp the in-phase part (like running a Peltier junction
backwards). Otherwise, no net power. Period.

   Mark L. Fergerson

There are energy scavenging techniques that can run off an ambient
temperature gradient, e.g. across an article of clothing.  You don't get
much power, but even a few tens of microwatts would be interesting for
some purposes.
Click to expand...
They require an energy differential, yes?


Mark L. Fergerson
 
On Fri, 20 Nov 2009 12:54:00 +0000, ChrisQ <meru@devnull.com> wrote:

John Larkin wrote:


The coolest current transformer is a second-harmonic DCCT, accurate to
parts-per-million from DC to many kilohertz.


Enquiring minds etc :). I thought at first that sounded like a
variation on the old fluxgate compass idea from ww2 and earlier, where
the earth's magnetic field varies the saturation of a toroidal ring and
the second harmonic amplitude recovered in 3 levels in 120 degree
segments, but it's quite different. Here's a good article on the principle:

cdsweb.cern.ch/record/1183400/files/CERN-BE-2009-019.pdf

Page 3 of 4 for the block diagram.

Using a feedback loop to cancel the induced magnetic field. Very neat.

Something new to learn in electronics every day :)...

Regards,

Chris
Click to expand...
No, more like an inside out mag-amp making a detector down to DC.
 
On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

<snip>

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.
Click to expand...
At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

;-)

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
 
On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
<excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."
Click to expand...
Ok, but what does IIV mean?

>;-)
 
krw wrote:
On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

;-)
Click to expand...

That he'll never be number one. :)


--
The movie 'Deliverance' isn't a documentary!
 
On Sat, 21 Nov 2009 10:23:29 -0600, krw wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news
service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

;-)
Click to expand...
Sorry, dont get it. What's the context?

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
 
On Sat, 21 Nov 2009 09:04:57 -0800, Fred Abse
<excretatauris@invalid.invalid> wrote:

On Sat, 21 Nov 2009 10:23:29 -0600, krw wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news
service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

;-)

Sorry, dont get it. What's the context?
Click to expand...
"Proteus IIV", DimBulb's playmate and Jamie's alter ego.
 
On Sat, 21 Nov 2009 10:23:29 -0600, krw <krw@att.bizzzzzzzzzzz> wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?
Click to expand...
---
Since putting smaller Roman numerals to the left of larger ones means to
subtract them from the larger, that's just a cutesy, dumb-ass way of
writing "3".

JF
 
On Sat, 21 Nov 2009 12:23:23 -0600, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 21 Nov 2009 10:23:29 -0600, krw <krw@att.bizzzzzzzzzzz> wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

---
Since putting smaller Roman numerals to the left of larger ones means to
subtract them from the larger, that's just a cutesy, dumb-ass way of
writing "3".
Click to expand...
Only works for one 'I'.
 
On Sat, 21 Nov 2009 11:58:39 -0600, krw wrote:

On Sat, 21 Nov 2009 09:04:57 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Sat, 21 Nov 2009 10:23:29 -0600, krw wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news
service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

;-)

Sorry, dont get it. What's the context?

"Proteus IIV", DimBulb's playmate and Jamie's alter ego.
Click to expand...
Ahh... I'd not seen that.

Maybe means "Ignorant, Irrelevant, Vacuous"

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
 
On Sat, 21 Nov 2009 12:25:11 -0600, krw <krw@att.bizzzzzzzzzzz> wrote:

On Sat, 21 Nov 2009 12:23:23 -0600, John Fields
jfields@austininstruments.com> wrote:

On Sat, 21 Nov 2009 10:23:29 -0600, krw <krw@att.bizzzzzzzzzzz> wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

---
Since putting smaller Roman numerals to the left of larger ones means to
subtract them from the larger, that's just a cutesy, dumb-ass way of
writing "3".

Only works for one 'I'.
Click to expand...
---
One 'I' is to the right of one, so they add to '2', but that sum is
still smaller 'V', and on its left, so it's subtracted, with the
difference being '3'.

That's why it's cutesy and dumb-ass.


JF
 
On Sat, 21 Nov 2009 09:04:57 -0800, Fred Abse
<excretatauris@invalid.invalid> wrote:

On Sat, 21 Nov 2009 10:23:29 -0600, krw wrote:

On Sat, 21 Nov 2009 07:05:36 -0800, Fred Abse
excretatauris@invalid.invalid> wrote:

On Mon, 16 Nov 2009 19:47:23 -0600, krw wrote:

snip

AH, so you are an expert of AC/DC . how's the swinging these days?

You two are a perfect pair.

At least I never get to see Proteus's posts, except as quotes. Google
gets filtered out here. I pray that he'll never get a proper news
service.

From Wikipedia:
"Proteus is a bacterial genus within the medically important group of
Enterobacteriaceae. Species most commonly associated with clinical
disease are Proteus mirabilis, Proteus vulgaris and Proteus penneri.
Proteus species are notorious in medical microbiological laboratories
because of their rapid swarming growth on commonly used agar plates."

Ok, but what does IIV mean?

;-)

Sorry, dont get it. What's the context?
Click to expand...
That P is so third rate that 'e can't form a proper roman numeral.
 
On Mon, 23 Nov 2009 09:24:08 -0800, Geoff <geoff@invalid.invalid>
wrote:

Will sea level rise if the polar caps melt?

Get a container. A tall one will work, like a tumbler.
Fill it about 3/4 full with tap water.

Add ice until the container is full but not so much that the container
overflows or the ice protrudes above the top. Place a cover over the
container to minimize evaporation, a saucer will do. Place the
container on a table and mark the side of it where the water level
appears. Make sure to choose the flattest part of the meniscus away
from any ice contact with the wall.

Let the ice melt.

Once the ice is completely melted, check the new water level.

Tell me again why sea level will rise?

Well, the south polar caps and other glaciers are on land, you say?
What is the volume of the ice on land, precisely? What is the relative
proportion of that volume of ice to the total volume of liquid water
in the oceans? What is the precise total surface area of the oceans?
When that 'precise' volume of ice is spread over the surface area of
the oceans how thick will it be? If you cannot answer these questions
Al Gore, you cannot predict sea level rise.
Click to expand...
You done gone and annoyed the leftist weenies again ;-)

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
 
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