thanks. As a real-world example an old crystal microphone could put out one volt peak-to-peak into one megohm if you talked close. So that's about.3 volts rms, p = e^2/r or 10^-7 watts. So I get 100 nanowatts, close enough.
You'd get 100 x more power from a one square cm solar cell, even from moonlight.
It does not matter if they improve the microphone efficiency to exactly 100% The amount of power in any reasonable voice is miniscule at best. And most of the power is in the lower part of the register, where the sound wavelengths are several meters long. And to get even a fraction of the power out of a wave, you need a microphone at least a quarter wavelength across.
So even if cell phone microphones were a foot in diameter, they'd only capture a few milliwatts on voice peaks. And cell phones need a couple watts of power full-time to output a watt or so to the antenna. No way, Jose, and by at least three zeros after the "1".
Yep, this offer is great for folks that subscribe to record clubs, 10-year gym contracts, "free" tire rotations, vacation time-shares, tenth-cone-free punch cards, and all that.
so this guy can design $26,000 wheelchairs that no one can afford. $12,000 electric mopeds that no one buys.
Call me not impressed.
And now he has some water filtration system, cost unknown, but probably pricey.
And a Stirling engine of unknown efficiency and reliability.
If you read between the lines of TFA you might get the impression that investors are not clamoring to invest in another expensive set of gadgets that are over-designed and over-priced and under-powered.
it's kinda sad. They tried. But the juggernauts ran them right over. Their technology was gee-whizzy and innovative. But they had a hard job getting anybody to buy into such a radical change.
So for some reason all these guys are getting terrific efficiency from their Stirling engines but everybody is being really shy and coy and squeamish about even hinting as to the efficiency they're getting. Use some common sense, people. The Stirling engine has been the next big thing for 160 years, and may very well continue to be that for just as long into the future.
Ah, no. The temp difference sets an UPPER LIMIT to the efficiency. There is no limit to how bad it can be. And a Stirling engine tends to be really poor as you need unobtainables such as perfect insulators with high thermal conductivity.
A single example of a govt-subsidized one-off experiment that has not been running for very long is a mighty poor flagship example.
When you can point to a Stirling engine that has been running for a year or two with minimal maintenance and is economical compared to the many proven alternatives, then we can talk.
Please show me a single verifiable efficiency number for a closed loop Stirling engine in use for more than 6 months in the real world. I have not been able to find one. That may be a clue.
* You don't arc-weld with those round oxy-acetylene goggles, at least not for long. You'll get sunburn on your face and blow out your retinas.
* If you want the outer panels to stay on, you weld them to the supporting framework, like from the INSIDE. There's nothing you can do from the outer side.
* If we assume the Enterprise is made of something better than mild steel, the welding would probably be done in an inert gas atmosphere.
* There's only one guy working on the ship at a time? That would take like 1073 years. Oh....
It's been refined for 160 years plus change. So it ought to be really spiffy, right? Well, no. There are definite upper limits to the efficiency of such a device. Most Stirling sites are very cagey when it comes to mentioning the efficiency of what they're selling. For good reason, it's terrible. Like 3 to 6 percent. That kinda explains why it's not in use everywhere, more like nowhere.
this is the usual hobson's choice. you load up some framework and WOW, 70% of the work is done for you! Whopee! Then the boss wants the buttons to update differently and you find it really hard to do that within the framework, but you manage by adding kludges in 73 places. Then you realize you really need a way to rollback or failover or fooswank and of course it's hard to impossible to wedge that into the framework. And then version 2 of the framework comes out and all your kludges you have to reimplement.
in other words the framework makes the first 70% easy, the next 20% difficult or slow, and the critically needed last 10 percent very difficult to impossible.
I've seen this time after time, with Hypercard, PowerBuilder, Notes, etc, etc, etc...
Let's assume these are the very best of next decade's solar cells, say 30% efficient. Let's guess they're about 10x15 cm. Also assume we are not in England so the sun shines maybe 30% of the time. crank, crank, crank.... this gadget can at best supply very nearly ONE FREEPIN WATT !!
This notebook I'm typing on draws about 30 watts, so this expensive gadget would let me run the laptop for about 50 minutes per day in Tuscon, Arizona.
Or looked at another way, in a year this thingy will produce about eight kilowatt hours, about sixty cents worth of power. If you'd kept your cash in the bank at 3% interest you'd have made exactly ten times as much, without the bother of keeping this thing pointed at the sun. not exactly an economic win of any sort,
I understand that demos may be simplified, but this one is ridiculous, for many reasons.
* There isn't any attempt made to check for actual x-rays. The crystal and geiger counter are both sensitive to a very wide spectrum.
* The sensors could be fooled by static discharges. Geiger counters and scintilating crystals are both very sensitive to electric fields, just what you expect to find around tape and adhesives and friction.
* The geiger counter is not a calibrated piece of lab equipment, but just about the cheapest handheld consumer device. Does not reflect well on the experimenters scientific accuracy.
* They don't take the slightest effort to filter out non x-rays. A simple piece of aluminum foil over the plexiglass cover would stop electric fields, the most probably confounding element. Even Roentgen was more scientific, determining that X-rays acted like light, in that they could be reflected and refracted. 130 years later and these guys can't even do the simple due diligence that's been in the books for over a century.
* These guys have no clue what's happening. A scientist would try to work up a theory and a mechanism for X-ray emission. Quite a challenge as x-ray radiation is almost always associated with abrupt electron acceleration near high-Z elements.
All in all the demo video is very shabby experimentation, I don't dare call it "science". If it was science they would try null experiments, say using other sources of sparks against their rather inappropriate sensors. This does not seem to have been done.
If you do the math, assuming you want to reflect an extra 1%, you have to cover about 3% of ground with 10 mil aluminum foil, you get that you'll need about 10 billion tons of aluminum.
That's about 35 years of world production.
And that foil is unlikely to last 35 years, so you can never get it done.
And for our next analysis, we will have Zbignew Brzenski give his opinion on quantum cryptography versus Enigma machines.
Why is it when a genius in field X has some free time, they think they can do immediately have deep insights in field Q?
----
As an obvious counterexample, a nuclear plant, to avoid disaster, needs continuous monitoring and maintenance by dozens of fallible humans, plus the critical reactor vessel gets steadily weaker due to neutron bombardment. It's not a question of "if", but of "when" something gives.
OTOH nuclear weapons, by comparison, are intrinsically inert. Only by a special sequence of ministrations can they be activated.
Personally I'd rather live next to something in category 2 than category 1.
Ethernet is more of a generic name than a specific thing. It's more like "soup" than it is like "VHS".
Ethernet started as a daisy-chained garden-hose-size coax cable with vampire taps. Then RG-58 with BNC connectors, then twisted pairs to a hub, then switching hubs, then wireless... Not much stayed the same, not speed, media, topology,... except maybe carrier-sense. It's basically a comforting name, with the Ethernet-of-the-day varying at the chef's whim.
Keeping the name while tossing out the last remaining bit of commonality is a bit bizarre.
I read TFA and was waiting for all the reasons this was a good idea. Like why all Buicks have three holes in each side. Or why glad bags are so much better with yellow and blue zippers. I expected to read that the machine was like, totally silent. Or that things ran, well, slicker. Maybe I missed a whole page of pluses? There gotta be a whole lot of pluses for a $4K box that you can't change the motherboard.
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Yes, Python 3.0 is a break.
But in the past and forseeable future, Python has been exceedingly helpful, much more than most languages, during upgrades.
Usually one has several months to try out new features-- they're in the current version but turned off until you ask for them with "future_builtins".
Plus there's often a backwards feature in the next version to revert back to old behavior.
Not to mention a -3 option to point out the lines in your old program that will need changing for version 3.
But sometimes the changes are so big they can't be encompassed by a compiler switch. Such it is with 3.0.
thanks. As a real-world example an old crystal microphone could put out one volt peak-to-peak into one megohm if you talked close. So that's about .3 volts rms, p = e^2/r or 10^-7 watts.
So I get 100 nanowatts, close enough.
You'd get 100 x more power from a one square cm solar cell, even from moonlight.
It does not matter if they improve the microphone efficiency to exactly 100% The amount of power in any reasonable voice is miniscule at best. And most of the power is in the lower part of the register, where the sound wavelengths are several meters long. And to get even a fraction of the power out of a wave, you need a microphone at least a quarter wavelength across.
So even if cell phone microphones were a foot in diameter, they'd only capture a few milliwatts on voice peaks. And cell phones need a couple watts of power full-time to output a watt or so to the antenna. No way, Jose, and by at least three zeros after the "1".
Yep, this offer is great for folks that subscribe to record clubs, 10-year gym contracts, "free" tire rotations, vacation time-shares, tenth-cone-free punch cards, and all that.
The rest of us value lack of lock-in.
so this guy can design $26,000 wheelchairs that no one can afford. $12,000 electric mopeds that no one buys.
Call me not impressed.
And now he has some water filtration system, cost unknown, but probably pricey.
And a Stirling engine of unknown efficiency and reliability.
If you read between the lines of TFA you might get the impression that investors are not clamoring to invest in another expensive set of gadgets that are over-designed and over-priced and under-powered.
This does not prove anything about E=mc2. You can't "prove" fundamental equations by twiddling bits.
They ASSUME that E=mc2, then use that equation to calculate the details of nuclear energies.
it's kinda sad. They tried. But the juggernauts ran them right over. Their technology was gee-whizzy and innovative. But they had a hard job getting anybody to buy into such a radical change.
11% is mighty good for a Stirling.
But lamentable as a diesel generator can do 33% and for 1/5 the initial cost.
Not many folks are going to spend five times as much for the privilege of burning three times as much fuel.
And the diesel has proven reliability and can be fixed most anywhere. While the Stirling has to be shipped to New Zealand if it goes awry.
So for some reason all these guys are getting terrific efficiency from their Stirling engines but everybody is being really shy and coy and squeamish about even hinting as to the efficiency they're getting. Use some common sense, people. The Stirling engine has been the next big thing for 160 years, and may very well continue to be that for just as long into the future.
Ah, no. The temp difference sets an UPPER LIMIT to the efficiency. There is no limit to how bad it can be. And a Stirling engine tends to be really poor as you need unobtainables such as perfect insulators with high thermal conductivity.
A single example of a govt-subsidized one-off experiment that has not been running for very long is a mighty poor flagship example.
When you can point to a Stirling engine that has been running for a year or two with minimal maintenance and is economical compared to the many proven alternatives, then we can talk.
Please show me a single verifiable efficiency number for a closed loop Stirling engine in use for more than 6 months in the real world. I have not been able to find one. That may be a clue.
Okay, think. It's been around for 160 years and you can only point to examples in cost-is-no-object applications. Does that tell you something?
Looks intriguing, but:
* You don't arc-weld with those round oxy-acetylene goggles, at least not for long. You'll get sunburn on your face and blow out your retinas.
* If you want the outer panels to stay on, you weld them to the supporting framework, like from the INSIDE. There's nothing you can do from the outer side.
* If we assume the Enterprise is made of something better than mild steel, the welding would probably be done in an inert gas atmosphere.
* There's only one guy working on the ship at a time? That would take like 1073 years. Oh....
your basic garbage has a high water content, up to 60%.
There is no way to come out ahead energy-wise if you're going to heat the water to 10,000 degrees. There isn't enough energy in the trash to do so.
Now perhaps a careful preliminary drying using waste heat might help, but that adds more cost and complexity.
It's been refined for 160 years plus change. So it ought to be really spiffy, right? Well, no. There are definite upper limits to the efficiency of such a device. Most Stirling sites are very cagey when it comes to mentioning the efficiency of what they're selling. For good reason, it's terrible. Like 3 to 6 percent. That kinda explains why it's not in use everywhere, more like nowhere.
this is the usual hobson's choice. you load up some framework and WOW, 70% of the work is done for you! Whopee! Then the boss wants the buttons to update differently and you find it really hard to do that within the framework, but you manage by adding kludges in 73 places. Then you realize you really need a way to rollback or failover or fooswank and of course it's hard to impossible to wedge that into the framework. And then version 2 of the framework comes out and all your kludges you have to reimplement.
in other words the framework makes the first 70% easy, the next 20% difficult or slow, and the critically needed last 10 percent very difficult to impossible.
I've seen this time after time, with Hypercard, PowerBuilder, Notes, etc, etc, etc...
one hundred forty pounds ?
Let's do a little math.
Let's assume these are the very best of next decade's solar cells, say 30% efficient. Let's guess they're about 10x15 cm. Also assume we are not in England so the sun shines maybe 30% of the time. crank, crank, crank.... this gadget can at best supply very nearly ONE FREEPIN WATT !!
This notebook I'm typing on draws about 30 watts, so this expensive gadget would let me run the laptop for about 50 minutes per day in Tuscon, Arizona.
Or looked at another way, in a year this thingy will produce about eight kilowatt hours, about sixty cents worth of power. If you'd kept your cash in the bank at 3% interest you'd have made exactly ten times as much, without the bother of keeping this thing pointed at the sun. not exactly an economic win of any sort,
I understand that demos may be simplified, but this one is ridiculous, for many reasons.
* There isn't any attempt made to check for actual x-rays. The crystal and geiger counter are both sensitive to a very wide spectrum.
* The sensors could be fooled by static discharges. Geiger counters and scintilating crystals are both very sensitive to electric fields, just what you expect to find around tape and adhesives and friction.
* The geiger counter is not a calibrated piece of lab equipment, but just about the cheapest handheld consumer device. Does not reflect well on the experimenters scientific accuracy.
* They don't take the slightest effort to filter out non x-rays. A simple piece of aluminum foil over the plexiglass cover would stop electric fields, the most probably confounding element. Even Roentgen was more scientific, determining that X-rays acted like light, in that they could be reflected and refracted. 130 years later and these guys can't even do the simple due diligence that's been in the books for over a century.
* These guys have no clue what's happening. A scientist would try to work up a theory and a mechanism for X-ray emission. Quite a challenge as x-ray radiation is almost always associated with abrupt electron acceleration near high-Z elements.
All in all the demo video is very shabby experimentation, I don't dare call it "science". If it was science they would try null experiments, say using other sources of sparks against their rather inappropriate sensors. This does not seem to have been done.
You can generate x-rays with significantly less than that (both voltage and current). Why do you think there's so much lead in a CRT, Hmmmm?
In a CRT you have milliamps of electrons at 20KV or thereabouts hitting a nickel mask, for thousands of hours.
In a strip of tape you have maybe a microamp at 1KV hitting plastic for a microsecond.
About thirteen orders of magnitude between them. Not to mention there's a steep quantum dropoff to zero emission around 13KV.
Using Occam's razor, static discharge is a much more plausible explanation.
Typical X-ray machines use 50 to 200 kilovolts and milliamps of electrons slamming into a tungsten target. Nothing less will do.
It's kinda unlikely Scotch (brand) tape can bypass all the bottlenecks and emit copious X-rays.
It's much more likely they're getting electrostatic discharges in the film. The New Age loonballs call it "Kirlian Photography".
I'll be glad to eat a hat if this pans out. Until then I'll just wear it.
If you do the math, assuming you want to reflect an extra 1%, you have to cover about 3% of ground with 10 mil aluminum foil, you get that you'll need about 10 billion tons of aluminum.
That's about 35 years of world production.
And that foil is unlikely to last 35 years, so you can never get it done.
And for our next analysis, we will have Zbignew Brzenski give his opinion on quantum cryptography versus Enigma machines.
Why is it when a genius in field X has some free time, they think they can do immediately have deep insights in field Q?
----
As an obvious counterexample, a nuclear plant, to avoid disaster, needs continuous monitoring and maintenance by dozens of fallible humans, plus the critical reactor vessel gets steadily weaker due to neutron bombardment. It's not a question of "if", but of "when" something gives.
OTOH nuclear weapons, by comparison, are intrinsically inert. Only by a special sequence of ministrations can they be activated.
Personally I'd rather live next to something in category 2 than category 1.
Ethernet is more of a generic name than a specific thing. It's more like "soup" than it is like "VHS".
Ethernet started as a daisy-chained garden-hose-size coax cable with vampire taps. Then RG-58 with BNC connectors, then twisted pairs to a hub, then switching hubs, then wireless... Not much stayed the same, not speed, media, topology,... except maybe carrier-sense. It's basically a comforting name, with the Ethernet-of-the-day varying at the chef's whim.
Keeping the name while tossing out the last remaining bit of commonality is a bit bizarre.
I read TFA and was waiting for all the reasons this was a good idea. Like why all Buicks have three holes in each side. Or why glad bags are so much better with yellow and blue zippers. I expected to read that the machine was like, totally silent. Or that things ran, well, slicker. Maybe I missed a whole page of pluses? There gotta be a whole lot of pluses for a $4K box that you can't change the motherboard.