Modern power control electronics can produce a smooth sign wave, at a pretty good efficiency. The first harmonic as at like the 8th overtone, which is easily filtered. However, there are motor controllers that don't use sign waves, but form the current to match the motor characteristics. Even better.
Here are two reasons why AC is generally better than DC at consumer level:
1: AC arcs are self-extinguishing every half cycle....
2: Human safety:...
The first is true, but the second is not so much. 60Hz current can scramble the coded signals used by your nervous system, in effect "crashing your network". And 60Hz can cause muscle contraction, it just shakes a bit. I think it is harder to let go when hit by 60Hz. It does depend on frequency, though, higher frequencies do not cause this. I think 400Hz was considered less dangerous, in that way.
It's beside the point,though. The application in question does not require long distance or high voltage. For one house, 24 volts might be fine.
I think the real news is, that they are using the newer high efficiency DC motor technology allowed by electronic motor controls. Brushes and mechanical commutators were why this was not done long ago.
... But deadly force should only be used to defend people, not stuff.
That is a common philosophy, but it is philosophy not law or even morality. Many people believe that deadly force is justified, morally at least, to protect property. The alternative is to allow criminals to steal anything that they can escape quickly with, and there is no way to stop them. That may not be practical.
Besides, I put part of my soul into much of what I have. The one who steals it steals part of me.
Firing a weapon in a populated area except in defense of life and limb is a colossally stupid idea and patently against the law, just because your privacy is being violated is no excuse.
A city person, no doubt...
We go target shooting in the back yard, here.
If a prowler was sneaking around people's property, looking over people's daughters. he would get shot with something a lot heavier than a bird-shot. They should expect no less for a drone...
Many people, who type professionally, find it less tiring to hit the capslock key and then type a letter, rather than having to hold down the shift key while typing a letter at the same time. Of course, it might depend on keyboard layout.
However, it is very bad to assume a small statistical usage means something is not needed. Like a seat belt, it might not be used very often, but if you need it and don't have it you could be in big trouble.
It is likely that no one, with any brains, would buy a keyboard with no capslock! 8-)
Yes, but it's distinguished from the steam engine, from what I understand, in that the power output is comparable enough to the margin of error that they're still in the process of verifying that it's actually doing something.
They seem to think it is doing "something". Exactly what, may be in question. 8-)
They are being cautious with the power levels. Microwave energy at high levels can be very dangerous, as shown by the injuries when Radar was being developed. I don't blame them for using the minimum drive levels, to get a reading.
It's one thing to question the very preliminary theory of operation for the thing, it's quite another to demand that it is doing nothing just because it would be inconvenient....
True.
If you have something that works, no theory is required to build one. People built things long before they invented the scientific method.
A good theory is -very- useful for improving things and making them more reliable. But it is not -required-.
It's worth noting that there's a big difference between those theories and this engine. With this engine, they're putting forward a piece of technology and saying, "We don't know how this works, but we're claiming it does." In the case of Newton and Einstein, they put forward a mathematical model that was internally consistent, and the question was whether it applied to reality....
This is much more like the invention of the steam engine. Look it up, they had steam engines working for many years with no valid theory at all. The designs changed radically, when they began to develop some parts of the theory. It was decades before they had it working right, but they got good use out of them, anyway.
Just because you don't have a theory (that works), doesn't mean the tech can't work. Theory is very helpful to technology, but technology does not -require- theory.
Except, claiming that you know it is a scam is just as "shaky" as claiming it is definitely a true thing.
Of course, we get trashed for having the courage to say "I don't know". So I understand some of the statements. Just be aware, when you have to lie to the public, and don't go believing your own "spin".
Most of the time, the real truth is that we -don't- know. We just suspect a lot... 8-)
There are a lot of traditional remedies, that actually work, that are not "pushed" because there is no way to make money on them. And no way to cover the cost of medical testing required, before you can say they work.
So those that know, use them. And those that don't, loose out.
Of course, there are many traditional remedies that don't work, or not enough to be better than new stuff. But not as many as the "establishment" claims.
When you read that HP was "a company founded in a garage by a pair of engineers ", that means that they took off their ties when they got home from their day jobs. After all, this was before the 60's... 8-)
Why is Belinda Gates referred to as Bill's 'better half'? That's so wrong on so many levels. You can say that as a 'joke', but written in an article, it's very wrong.
Well... we know how bad he is, so she -has- to be better, right? 8-)
It's true that rapidly advancing tech requires learning new stuff.
But the problem is marketers changing the UI appearance to make you think it is new tech, when it is not. You put forth the effort to learn the new UI, and then find that it was a fraud and there was no advantage to it. All your effort is wasted!
The difference in the younger people is just that they have not had that happen to them as many times, yet... 8-)
I did the same thing, in an automatic. Slowed for a stop sign, reached for the center gearshift and lifted my left foot.
Then I pushed down the "clutch" and hit the left end of the wide brake pedal. We found out that the car had -really- good brakes!! One of the guys in the back seat ended up in the front... 8-)
Slashdot Mirror
You don't need new wire, you just need new sockets so you don't plug into the wrong voltage. There are already DC socket standards.
But if you just wire the air conditioner to the solar panels, you still save a lot.
Modern power control electronics can produce a smooth sign wave, at a pretty good efficiency. The first harmonic as at like the 8th overtone, which is easily filtered. However, there are motor controllers that don't use sign waves, but form the current to match the motor characteristics. Even better.
Here are two reasons why AC is generally better than DC at consumer level:
1: AC arcs are self-extinguishing every half cycle. ...
2: Human safety: ...
The first is true, but the second is not so much. 60Hz current can scramble the coded signals used by your nervous system, in effect "crashing your network". And 60Hz can cause muscle contraction, it just shakes a bit. I think it is harder to let go when hit by 60Hz. It does depend on frequency, though, higher frequencies do not cause this. I think 400Hz was considered less dangerous, in that way.
It's beside the point,though. The application in question does not require long distance or high voltage. For one house, 24 volts might be fine.
I think the real news is, that they are using the newer high efficiency DC motor technology allowed by electronic motor controls.
Brushes and mechanical commutators were why this was not done long ago.
... But deadly force should only be used to defend people, not stuff.
That is a common philosophy, but it is philosophy not law or even morality.
Many people believe that deadly force is justified, morally at least, to protect property.
The alternative is to allow criminals to steal anything that they can escape quickly with, and there is no way to stop them.
That may not be practical.
Besides, I put part of my soul into much of what I have. The one who steals it steals part of me.
Firing a weapon in a populated area except in defense of life and limb is a colossally stupid idea and patently against the law, just because your privacy is being violated is no excuse.
A city person, no doubt...
We go target shooting in the back yard, here.
If a prowler was sneaking around people's property, looking over people's daughters. he would get shot with something a lot heavier than a bird-shot. They should expect no less for a drone...
Many people, who type professionally, find it less tiring to hit the capslock key and then type a letter, rather than having to hold down the shift key while typing a letter at the same time. Of course, it might depend on keyboard layout.
However, it is very bad to assume a small statistical usage means something is not needed. Like a seat belt, it might not be used very often, but if you need it and don't have it you could be in big trouble.
It is likely that no one, with any brains, would buy a keyboard with no capslock! 8-)
s/hung/hanged/
"Hanged" is killed quickly.
"Hung" is slow starving to death.
I think his usage was correct. 8-}
That was in a message, but I don't think that was what the scientists were saying.
The force was small, but well above the noise.
Yes, but it's distinguished from the steam engine, from what I understand, in that the power output is comparable enough to the margin of error that they're still in the process of verifying that it's actually doing something.
They seem to think it is doing "something". Exactly what, may be in question. 8-)
They are being cautious with the power levels. Microwave energy at high levels can be very dangerous, as shown by the injuries when Radar was being developed. I don't blame them for using the minimum drive levels, to get a reading.
It's one thing to question the very preliminary theory of operation for the thing, it's quite another to demand that it is doing nothing just because it would be inconvenient. ...
True.
If you have something that works, no theory is required to build one. People built things long before they invented the scientific method.
A good theory is -very- useful for improving things and making them more reliable. But it is not -required-.
There is ZERO science behind this. NONE. They have no viable working theory as to why it would even work. ...
Science is a -method- for doing research. It is not a theory.
The word is often used wrong, even by some scientists.
It's worth noting that there's a big difference between those theories and this engine. With this engine, they're putting forward a piece of technology and saying, "We don't know how this works, but we're claiming it does." In the case of Newton and Einstein, they put forward a mathematical model that was internally consistent, and the question was whether it applied to reality. ...
This is much more like the invention of the steam engine. Look it up, they had steam engines working for many years with no valid theory at all. The designs changed radically, when they began to develop some parts of the theory. It was decades before they had it working right, but they got good use out of them, anyway.
Just because you don't have a theory (that works), doesn't mean the tech can't work.
Theory is very helpful to technology, but technology does not -require- theory.
Except, claiming that you know it is a scam is just as "shaky" as claiming it is definitely a true thing.
Of course, we get trashed for having the courage to say "I don't know". So I understand some of the statements. Just be aware, when you have to lie to the public, and don't go believing your own "spin".
Most of the time, the real truth is that we -don't- know. We just suspect a lot... 8-)
Um ... the phama companies can't make money on it?
There are a lot of traditional remedies, that actually work, that are not "pushed" because there is no way to make money on them. And no way to cover the cost of medical testing required, before you can say they work.
So those that know, use them. And those that don't, loose out.
Of course, there are many traditional remedies that don't work, or not enough to be better than new stuff. But not as many as the "establishment" claims.
When you read that HP was "a company founded in a garage by a pair of engineers ", that means that they took off their ties when they got home from their day jobs.
After all, this was before the 60's... 8-)
A legal system that elects judges is always going to fail.
A legal system that does -not- elect judges is also going to fail. Just in a different mode...
Here is another fucking NAZI that thinks they can control everybody else.
Bad writing slows down people's reading. It is a royal pain. It is also a favor to let someone know what they need to do, to be read.
It has gotten so bad that many people just skip over badly written messages, including me.
I have it on good authority that half of all people are stupider than average.
True. However, hardly anyone is anywhere near "average".
Depending, of course, on your definition of "anywhere near"... 8-)
Why is Belinda Gates referred to as Bill's 'better half'?
That's so wrong on so many levels. You can say that as a 'joke', but written in an article, it's very wrong.
Well... we know how bad he is, so she -has- to be better, right? 8-)
It depends very much on what is being done with the equipment.
Some have never been updated and updating it can get you fired!
Some are updated when new hardware is purchased, but not otherwise unless a definate problem shows up.
(Those are not usually connected to any network or internet.)
Some are updated about two weeks after updates are released, unless zero-day exploits are reported.
A few are updated immediatly. Either for hobbies or as early tests for the other machines. (Or both at once.)
It's true that rapidly advancing tech requires learning new stuff.
But the problem is marketers changing the UI appearance to make you think it is new tech, when it is not. You put forth the effort to learn the new UI, and then find that it was a fraud and there was no advantage to it. All your effort is wasted!
The difference in the younger people is just that they have not had that happen to them as many times, yet... 8-)
Yes, I drove a "column shift" way back "when". It was actually not so bad, the reflexes were similar to the floor shifter.
But the column shifters were more loose, particularly after they were no longer brand new. I like the floor shifter better.
I did the same thing, in an automatic. Slowed for a stop sign, reached for the center gearshift and lifted my left foot.
Then I pushed down the "clutch" and hit the left end of the wide brake pedal.
We found out that the car had -really- good brakes!!
One of the guys in the back seat ended up in the front... 8-)
The difference between Magic and Technology, is that technology -works-. 8-)
It's still obsolete if it meets specs, and you can't maintain it if it breaks because it's too old.
The word you want is "obsolescent". 8-)