Re: Non-invasive Pressure Gauge?

calibrated thumb?

yes i can do that but it;s still an interesting problem to design an
accurate cheap
external gauge.

wle.

wle said:

calibrated thumb?

yes i can do that but it;s still an interesting problem to design an
accurate cheap
external gauge.

An impossible problem, more likely.

Quoted message said:

An impossible problem, more likely.

ah.
that is what they told edison.
though tesla solved many of the same problems better.

wle.

wle said:

Quoted message said:

An impossible problem, more likely.

ah.
that is what they told edison.
though tesla solved many of the same problems better.

wle.

Yeah, that's why power transmission is wireless today.

no, but that is why motors, generators, transmission lines and
transforrmers use alternating current instead of dc..

actually transformers don;t do anything on dc, and they make most
of the alternating current network feasible.

wle.

it;s why it is based on AC and not DC..

wle.

Peter Cole said:

Yeah, that's why power transmission is wireless today.

ITYM "that's why power transmission is AC today"

Edison was a huge foe of AC. Indeed, he designed the Electric Chair as
an AC device because he thought it would be more deadly.

Westinghouse bought Tesla's AC patents. The rest is history.

--
BMO

Let's not forget to give most of the credit to Steinmetz, where it is due.

right, edison was a DC guy.

AC won even though the powerful and rich edison backed the other team.

AC was infinitely better, and cheaper.

the original poster who said "that's why power transmission is AC
today" ,
i think was being sarcastic.

as in, rudely making fun of tesla;s attempts to send power wirelessly,
which he never perfected.

i think that is what he meant.

wle.

sorry i meant to type:
------
the original poster who said "that's why power transmission is
wireless
today" ,
i think was being sarcastic.
------

wle.

This all has me wondering how often you guys pump up your eyeballs. I
may not be doing it often enough, and rolling out the door with soft
eyeballs. Will this change the handling of my eyelids?

Monk said:

This all has me wondering how often you guys pump up your eyeballs. I
may not be doing it often enough, and rolling out the door with soft
eyeballs. Will this change the handling of my eyelids?

{rolls eyes}

Hmm. Not too much resistance.

:-D

On 9 May 2005 04:00:17 -0700, "Monk" <[email hidden]>

Quoted message said:

This all has me wondering how often you guys pump up your eyeballs. I
may not be doing it often enough, and rolling out the door with soft
eyeballs. Will this change the handling of my eyelids?

Dear Monk,

Typically, an eye exam will check for open-angle glaucoma
three ways because the disease is painless, irreversible,
and unnoticed by the patient in the first stages, but can
usually be controlled by drugs.

First, you play the dull video game in which you stare at a
spot on well-lit, boring white wall and push a button
whenever you notice a faint white dot appear here and there.
The test is checking for blind spots other than the normal
ones created by your optic nerve entering the back of the
eyeball. (The spots are to the outside and a bit below when
you look straight ahead--a red dot on a black piece of paper
will disappear if you move it close to your nose just
right.)

Open-angle glaucoma leads to an arc of new blind spots,
arctuate scotomas. They're permanent and enlarge, but you
aren't likely to notice them in the early stages--you can't
see them any more than you can see your normal blind spots.

Second, a peek into each eyeball (and possibly a photograph)
checks for increased cupping of the optic nerve. A bit of a
dent is normal, but open-angle glaucoma soon leads to the
dent enlarging. This is also irreversible and a bad thing.

Third, intra-ocular pressure is checked--10 to 20 mm Hg is
normal, 23 mm is often considered the cut-off for
controlling the disease. One way to check such a delicate
pressure involves pressing the flat end of rod against the
eye. This is better than a poke in the eye with a sharp
stick, but the more modern method uses just a puff of air
and some clever tricks.

The elevated pressure is the hallmark of the disease. The
"angle" is the name for the natural anatomical outlet. In
closed-angle glaucoma (typically traumatic), something
bashed you in the eye, the angle is swollen shut, and
pressure is rising because the fluid can't escape. Get
surgery or go blind.

In open-angle glaucoma, the angle is demonstrably open, but
pressure is faintly elevated, so the optic nerve is slowly
cupping and blind spots are appearing.

About 90 out of a hundred patients can arrest the disease
with a tedious regimen of drugs applied as eyedrops.
Glaucoma is a disease of age, so the elderly patients often
have trouble maintaining the twice-a-day, four-times-a-day
schedule.

Of the ten patients per 100 who do not respond to drugs,
about two-thirds respond well to surgery that consists of
carving a flap in the eye and sewing it up loosely--there
are numerous flap patterns, but the aim is a leaky flap.

The remaining patient goes blind.

Or so I heard from an eye-surgeon studying for her boards. I
also learned other interesting medical terms. If a patient's
nasal bridge interferes with the doctor's attempt to peer
into the eye at an angle, the physician may privately
complain about an "enormous honker." This famous painting
shows the secret desire of many eye surgeons when faced with
impressive nasal development:

http://www.answers.com/topic/federico-da-montefeltro

Federico da Montefeltro lost his right eye in a training
accident, a jousting match, or a sword fight (accounts vary)
and either lost the bridge of his nose, too, or else had the
wound trimmed to improve his remaining peripheral vision to
his right (accounts vary).

Anyway, you want to have your eyeball pressure checked now
and then, not to see if they're going soft like bike tires,
but to make sure that they're not over-inflated. If you do
this often enough, you may not go blind.

Carl Fogel

On 9 May 2005 04:00:17 -0700, "Monk" <[email hidden]>

Quoted message said:

This all has me wondering how often you guys pump up your eyeballs. I
may not be doing it often enough, and rolling out the door with soft
eyeballs. Will this change the handling of my eyelids?

Dear Monk,

Typically, an eye exam will check for open-angle glaucoma
three ways because the disease is painless, irreversible,
and unnoticed by the patient in the first stages, but can
usually be controlled by drugs.

First, you play the dull video game in which you stare at a
spot on well-lit, boring white wall and push a button
whenever you notice a faint white dot appear here and there.
The test is checking for blind spots other than the normal
ones created by your optic nerve entering the back of the
eyeball. (The spots are to the outside and a bit below when
you look straight ahead--a red dot on a black piece of paper
will disappear if you move it close to your nose just
right.)

Open-angle glaucoma leads to an arc of new blind spots,
arctuate scotomas. They're permanent and enlarge, but you
aren't likely to notice them in the early stages--you can't
see them any more than you can see your normal blind spots.

Second, a peek into each eyeball (and possibly a photograph)
checks for increased cupping of the optic nerve. A bit of a
dent is normal, but open-angle glaucoma soon leads to the
dent enlarging. This is also irreversible and a bad thing.

Third, intra-ocular pressure is checked--10 to 20 mm Hg is
normal, 23 mm is often considered the cut-off for
controlling the disease. One way to check such a delicate
pressure involves pressing the flat end of rod against the
eye. This is better than a poke in the eye with a sharp
stick, but the more modern method uses just a puff of air
and some clever tricks.

The elevated pressure is the hallmark of the disease. The
"angle" is the name for the natural anatomical outlet. In
closed-angle glaucoma (typically traumatic), something
bashed you in the eye, the angle is swollen shut, and
pressure is rising because the fluid can't escape. Get
surgery or go blind.

In open-angle glaucoma, the angle is demonstrably open, but
pressure is faintly elevated, so the optic nerve is slowly
cupping and blind spots are appearing.

About 90 out of a hundred patients can arrest the disease
with a tedious regimen of drugs applied as eyedrops.
Glaucoma is a disease of age, so the elderly patients often
have trouble maintaining the twice-a-day, four-times-a-day
schedule.

Of the ten patients per 100 who do not respond to drugs,
about two-thirds respond well to surgery that consists of
carving a flap in the eye and sewing it up loosely--there
are numerous flap patterns, but the aim is a leaky flap.

The remaining patient goes blind.

Or so I heard from an eye-surgeon studying for her boards. I
also learned other interesting medical terms. If a patient's
nasal bridge interferes with the doctor's attempt to peer
into the eye at an angle, the physician may privately
complain about an "enormous honker." This famous painting
shows the secret desire of many eye surgeons when faced with
impressive nasal development:

http://www.answers.com/topic/federico-da-montefeltro

Federico da Montefeltro lost his right eye in a training
accident, a jousting match, or a sword fight (accounts vary)
and either lost the bridge of his nose, too, or else had the
wound trimmed to improve his remaining peripheral vision to
his right (accounts vary).

Anyway, you want to have your eyeball pressure checked now
and then, not to see if they're going soft like bike tires,
but to make sure that they're not over-inflated. If you do
this often enough, you may not go blind.

Carl Fogel

wle said:

actually transformers don;t do anything on dc, and they make most
of the alternating current network feasible.

On the contrary, transformers can do all sorts of interesting things on
DC -- blow fuses, smoke, catch fire, etc.

--
Ray Heindl
(remove the Xs to reply)

Ray Heindl said:

wle said:

actually transformers don;t do anything on dc, and they make most
of the alternating current network feasible.

On the contrary, transformers can do all sorts of interesting things

on

Quoted message said:

DC -- blow fuses, smoke, catch fire, etc.

well, maybe by 'interesting' i should have said 'work'.
as in transform.

wle.

Quoted message said:

--
Ray Heindl
(remove the Xs to reply)

Peter Cole said:

An impossible problem, more likely.

You can do it with cars pretty easily. Knowing the area of the
contact patch and the pressure of the tires, you can derive the
weight of the car (saw it on "Bill Nye, the Science Guy," or some
such show). Conversely, knowing the weight, deriving the pressure
is just solving for another variable (assuming equal pressure in
all four tires).

However, I don't know how well this translates to a bicycle,
given its light weight.

Larry Coon
University of California

Larry Coon said:

Peter Cole said:

An impossible problem, more likely.

You can do it with cars pretty easily. Knowing the area of the
contact patch and the pressure of the tires, you can derive the
weight of the car (saw it on "Bill Nye, the Science Guy," or some
such show). Conversely, knowing the weight, deriving the pressure
is just solving for another variable (assuming equal pressure in
all four tires).

However, I don't know how well this translates to a bicycle,
given its light weight.

Larry Coon
University of California

Calculate backwards,you know your weight.
Ride through a puddle and then look at the width of your tyre print.

Marty