It wasn't just something he posted on his blog. His memo was approved by the committee. It just happened that the committee quickly retracted the memo after their true masters (their largest campaign contributors) expressed their disapproval.
ARM has 730 employees. Average revenue per employee is $287K. For comparison, Microsoft has an average revenue per employee of $646K (and 57,000 employees)
Think again, Dr. Out of the millions of installed DVD players out there, 5% will come to hundreds of thousands of players. And if you consider that there is probably a larger proportion of older players out there (the study seemed to weight them equally, or even be biased towards new players), the number of incompatible players will be even higher.
Wrong. DC is very useful for long distance power transmission -- it is both cheaper and easier for distances over about 300-400km. Here are a couple links:
How sad. That post is rated +5 Informative and it is wrong. Which could have been checked by anyone in 10 seconds by looking up the shares outstanding (13.1M) and the float (7.1M) on yahoo or whatever. That comes to a float of about 54% of shares outstanding.
How efficient can the convection tower possibly be? It is a heat engine, so the theoretical max efficiency is (T2-T1)/T2, with temperature in Kelvin. I can't imagine that the blacktop or whatever heats up more than 50K above the outside air temperature. So that max efficiency is about 50/300, or less than 17%. That's theoretical max. In reality, I guess the actual efficiency is much lower.
Do you have any numbers for how much electrical energy per square meter one of the convection towers can generate per year?
Your figure of $0.035/kWh assumes that wind is only generating a fraction amount of the country's power, as it is today in America.
As others have pointed out to you, you have made a mistake in scaling wind power up to the sole power source for America while assuming the same cost as when it only provides a small fraction of the power.
The problem is that wind provides "low quality" power. In most US locations, the average power generated over a year from a wind turbine is less than 20% of the peak power on the turbine nameplate. Also, keep in mind that many of the sites used for wind power today have natural land Venturi formations that concentrate the wind. If you scaled wind power up to cover the countryside, many sites you would be forced to use would be lower quality (you might try to put the turbines only in the best wind sites, but then you have to transport the power further and line losses are higher, so you can't really eliminate this problem).
Since peak power demand will certainly not correspond perfectly with peak wind supply, you cannot just take the energy consumed in the US per year and divide by the energy generated by a wind turbine per year and divide to get the number of turbines required. You will probably need to double or triple the number you give so that you can generate enough power to provide peak demand at times when the average wind in the country is low. Otherwise, rolling blackouts.
So, the real cost of supplying America's power demands sole with wind turbines is at least double or triple what you quote.
Personally, I think solar has more potential than wind, although it is also too expensive right now. But photovoltaics are much lower maintenance than turbines, and I think photovoltaics have more potential to increase the energy generated per dollar of cost (by increasing efficiency and/or reducing manufacturing costs). Also, the energy density available to be harnessed is much higher for solar than wind (in the US, there is about 200 W/m^2 of solar available averaged over a year, compared to only about 6 W/m^2 of wind).
I guess that in the long run, the best source of energy will be photovoltaics combined with some efficient energy storage mechanism (flywheels or pumped water towers perhaps?), with some amount of nuclear power plants providing additional capacity at night or during extended low-sunlight periods. (Okay, in the REALLY long term nuclear fusion may become feasible, but that has been 30 years away for each of the past 30 years)
But all of this is mostly pie-in-the-sky. If you really want to help the environment, the best way is to have better insulated homes and businesses with higher thermal mass, geo-thermal heatpumps (where feasible), replace incandescent light-bulbs with compact fluorescents, use mass-transit, car-pooling, or lobby for better mass-transit in your area, and try to drive the most fuel efficient car you can and drive it as little as possible.
L2 is about 1/6 further from the Earth than the moon, and L3 is a tiny bit further from the Earth than the moon. Normally, a further orbit will take longer to go around the earth than a closer orbit. But at L2 and L3, a little extra gravity is provided by the moon, but in the exact same direction as the Earth's gravity, and that is enough to speed the further orbit up so that it takes the same time as the moon to go around.
The "missing" force you are looking for might be thought of as the "centrifugal" force, which isn't a "real" force but feels real to someone going around in a circle.
It becomes especially bad when you get a group of like-minded individuals together, each patting each other on the back and removing any insecurities about what they're doing. Soon you have a bunch of anti-social weenies who are certain that their theft is somehow bettering the world.
For a minute there, I thought you were talking about Enron or Worldcom execs (or maybe Microsoft execs?)
Re:Another PDA Whoopee!!!
on
PDAs, PDAs
·
· Score: 1
I haven't yet been tempted to replace my pocket paper-notebook with a PDA yet, but if I were to do so, I would go for something like the Psion 5 with a keyboard and 640 pixel wide screen.
But I really don't see much benefit over a good paper notebook. My notebook has a calendar section, an addressbook section, and blank paper for notes. And it is FAST!
The only thing that would tempt we to get a PDA is if I could have easy wireless shell access to telnet to a UNIX box wherever I go. Does this exist? It seems the the G3 wireless networks are just being built in the US and won't be ready for a couple years.
"Hunter announced Cree had landed the services of Shuji Nakamura, who has attained legendary status in the optoelectronics field."
I read this article a couple months ago and I haven't heard anything about it since. None of the articles given in the story mention anything but his professor job. Is Nakamura working for CREE or not?
Is there any possibility of building Freenet capability into existing web browsers? So we could just type a URL like fnet://key=k3jdJd8LDjdk/ and access the file?
Corvis' switch is probably using semiconductor optical amplifier (SOA) technology. To make an NxN switch, you passively split each of N incoming signals into N parts, and then send each part through an SOA (N^2 total SOA's).
When there is no current applied to an SOA, it is a strong absorber. So you only apply current to N of the N^2 SOA's, and those will be the only paths that allow light to pass. Then you take the N^2 paths and combine them in an interleaved pattern back into N paths forming the outputs of the switch.
The article I read claims Corvis' switch is 6x6. The advantage over MEMS is that there are no moving parts. The disadvantage is that you cannot easily make big switches since this scales as N^2, and that the noise figure is fundamentally high because of the 1XN splitting loss.
1) Transit to satellite: 120ms
2) Unknown delay: x
3) Transit to groundstation: 120ms
4) Some typical ping time on wired Internet (roundtrip from groundstation to ping site to groundstation): y
5) Transit to satellite: 120ms
6) Unknown delay: x
7) Transit to home: 120ms
Add it all up and we have 480ms + 2x + y. Seems to me that could easily be 900ms.
"there are few good reasons to stare at the face of the person you're talking to"
Most people I know would disagree strongly with this statement. I know that when I am talking with someone in person, I spend a great deal of time looking at that person's face to see reactions to what I am saying, or to draw some additional context out of what the person is saying. While it is possible to get some of that from the voice intonations when speaking on the phone, I know that I much prefer having conversations in person rather than on the phone because the visual cues add a lot to the conversation.
They also review Kodak's Picture CD where you can take your standard print film to a regular film development house and for about $8-10 extra get back a CD with your pictures in addition to the prints. (resolution about 1.5K by 1K, but equivalent in quality to most 2Megapixel cameras)
Does the linux M15 build work with encryption? The M14 required a special build to work with crypto, and the crypto FAQ hasn't been updated in a while.
If the drum is mounted with a horizontal rotation axis, then the forklift WOULD have difficulty turning...
Oops, I had typed in the last sentence as an afterthought, but I just realized that the part about it not tilting was wrong. If the axis of rotation of the drum is horizontal, of course the drive would tilt if the forklift turned, just like a precessing gryoscope. Duh. So it must be that the drum drive had the platter mounted vertically (horizontal axis of rotation), since if it were mounted like a dinner plate, there would be no problem.
The trick about things with a lot of angular momentum is that they have a certain axis (vector) about which that angular momentum exists, and that AXIS resists rotation. Translating the axis but keeping it pointing in the same direction is easy.
One example of this is that if you were to make a flywheel-powered automobile, and you set the flywheel spinning with a vertical axis of rotation, then your car will be able to turn corners without difficulty but transitioning from a level road to a hill will be a disaster (incidentally, the solution is counter-rotating flywheels).
Before this gets even more off topic, the point is that the story about the drum drive either has some details wrong, or it is apocryphal. If the drum drive has a vertical angular momentum vector, than the forklift should have no troubles unless it tries to go up a ramp. If the drum is mounted with a horizontal rotation axis, then the forklift WOULD have difficulty turning, but the drive would NOT stand on one leg -- it would simply resist the turn, probably holding its orientation while the forklift turns underneath it (of course, it could fall off the edge of the forklift....)
The article doesn't say much about how it works. It sounds like it may be using the silicon micro-mirror technology developed by Texas Instruments where silicon is polished and etched into thousands of tiny, deflectable micro-mirrors, each one controlled by a transistor.
Slashdot Mirror
It wasn't just something he posted on his blog. His memo was approved by the committee. It just happened that the committee quickly retracted the memo after their true masters (their largest campaign contributors) expressed their disapproval.
ARM has 730 employees. Average revenue per employee is $287K. For comparison, Microsoft has an average revenue per employee of $646K (and 57,000 employees)
The Archos ARCDisk uses a 1.8" HD unit, measures about 3" x 3" x 0.35", and is available now (amazon.com sells it, for example)
Archos ARCdisk
DrEldarion wrote "5% isn't very significant"
Think again, Dr. Out of the millions of installed DVD players out there, 5% will come to hundreds of thousands of players. And if you consider that there is probably a larger proportion of older players out there (the study seemed to weight them equally, or even be biased towards new players), the number of incompatible players will be even higher.
The speed of sound in air at sea level is about 340 m/s. Two miles is about 3219 meters. One gee is about 9.8 m/s^2.
_ __21.16
dist = x = integral( v(t) dt ) = integral( a t dt ) = 0.5 a t^2
v = a t --> t = v / a
x = 0.5 a ( v / a )^2 = 0.5 v^2 / a
a = 0.5 v^2 / x = 0.5 v^2 / 3219 = v^2 / 6438
gees = ( s * 340 )^2 / 6438 / 9.8
= s^2 * 1.83
speed__gees
(mach)_(std grav)
1______1.83
2______7.32
3_____16.47
3.4
So, your statement is a bit off. Zero to MACH 3.4 in 2 miles requires more than 20 gee's. But Zero to MACH 1 in 2 miles only requires 1.8 gee's.
Wrong. DC is very useful for long distance power transmission -- it is both cheaper and easier for distances over about 300-400km. Here are a couple links:
Pacific Intertie
Gas to wire PDF (has some cost graphs vs. distance for AC and DC)
The really sad thing is that the parent rated +5, and it is WRONG that there is no mention of noise. Ah, slashdot moderators.
How sad. That post is rated +5 Informative and it is wrong. Which could have been checked by anyone in 10 seconds by looking up the shares outstanding (13.1M) and the float (7.1M) on yahoo or whatever. That comes to a float of about 54% of shares outstanding.
How efficient can the convection tower possibly be? It is a heat engine, so the theoretical max efficiency is (T2-T1)/T2, with temperature in Kelvin. I can't imagine that the blacktop or whatever heats up more than 50K above the outside air temperature. So that max efficiency is about 50/300, or less than 17%. That's theoretical max. In reality, I guess the actual efficiency is much lower.
Do you have any numbers for how much electrical energy per square meter one of the convection towers can generate per year?
Your figure of $0.035/kWh assumes that wind is only generating a fraction amount of the country's power, as it is today in America.
As others have pointed out to you, you have made a mistake in scaling wind power up to the sole power source for America while assuming the same cost as when it only provides a small fraction of the power.
The problem is that wind provides "low quality" power. In most US locations, the average power generated over a year from a wind turbine is less than 20% of the peak power on the turbine nameplate. Also, keep in mind that many of the sites used for wind power today have natural land Venturi formations that concentrate the wind. If you scaled wind power up to cover the countryside, many sites you would be forced to use would be lower quality (you might try to put the turbines only in the best wind sites, but then you have to transport the power further and line losses are higher, so you can't really eliminate this problem).
Since peak power demand will certainly not correspond perfectly with peak wind supply, you cannot just take the energy consumed in the US per year and divide by the energy generated by a wind turbine per year and divide to get the number of turbines required. You will probably need to double or triple the number you give so that you can generate enough power to provide peak demand at times when the average wind in the country is low. Otherwise, rolling blackouts.
So, the real cost of supplying America's power demands sole with wind turbines is at least double or triple what you quote.
Personally, I think solar has more potential than wind, although it is also too expensive right now. But photovoltaics are much lower maintenance than turbines, and I think photovoltaics have more potential to increase the energy generated per dollar of cost (by increasing efficiency and/or reducing manufacturing costs). Also, the energy density available to be harnessed is much higher for solar than wind (in the US, there is about 200 W/m^2 of solar available averaged over a year, compared to only about 6 W/m^2 of wind).
I guess that in the long run, the best source of energy will be photovoltaics combined with some efficient energy storage mechanism (flywheels or pumped water towers perhaps?), with some amount of nuclear power plants providing additional capacity at night or during extended low-sunlight periods. (Okay, in the REALLY long term nuclear fusion may become feasible, but that has been 30 years away for each of the past 30 years)
But all of this is mostly pie-in-the-sky. If you really want to help the environment, the best way is to have better insulated homes and businesses with higher thermal mass, geo-thermal heatpumps (where feasible), replace incandescent light-bulbs with compact fluorescents, use mass-transit, car-pooling, or lobby for better mass-transit in your area, and try to drive the most fuel efficient car you can and drive it as little as possible.
L2 is about 1/6 further from the Earth than the moon, and L3 is a tiny bit further from the Earth than the moon. Normally, a further orbit will take longer to go around the earth than a closer orbit. But at L2 and L3, a little extra gravity is provided by the moon, but in the exact same direction as the Earth's gravity, and that is enough to speed the further orbit up so that it takes the same time as the moon to go around.
The "missing" force you are looking for might be thought of as the "centrifugal" force, which isn't a "real" force but feels real to someone going around in a circle.
It becomes especially bad when you get a group of like-minded individuals together, each patting each other on the back and removing any insecurities about what they're doing. Soon you have a bunch of anti-social weenies who are certain that their theft is somehow bettering the world.
For a minute there, I thought you were talking about Enron or Worldcom execs (or maybe Microsoft execs?)
But I really don't see much benefit over a good paper notebook. My notebook has a calendar section, an addressbook section, and blank paper for notes. And it is FAST!
The only thing that would tempt we to get a PDA is if I could have easy wireless shell access to telnet to a UNIX box wherever I go. Does this exist? It seems the the G3 wireless networks are just being built in the US and won't be ready for a couple years.
I don't care how my service comes, but this is what I want:
(1) minimum 384 kbps, both ways, 24 hours per day
(2) static IP addresses with reverse DNS set to my domain name
(3) permission to run (low-volume) servers
I haven't found any cable provide that has that, but Speakeasy DSL and Telocity DSL do.
I read this article a couple months ago and I haven't heard anything about it since. None of the articles given in the story mention anything but his professor job. Is Nakamura working for CREE or not?
Is there any possibility of building Freenet capability into existing web browsers? So we could just type a URL like fnet://key=k3jdJd8LDjdk/ and access the file?
Corvis' switch is probably using semiconductor optical amplifier (SOA) technology. To make an NxN switch, you passively split each of N incoming signals into N parts, and then send each part through an SOA (N^2 total SOA's).
When there is no current applied to an SOA, it is a strong absorber. So you only apply current to N of the N^2 SOA's, and those will be the only paths that allow light to pass. Then you take the N^2 paths and combine them in an interleaved pattern back into N paths forming the outputs of the switch.
The article I read claims Corvis' switch is 6x6. The advantage over MEMS is that there are no moving parts. The disadvantage is that you cannot easily make big switches since this scales as N^2, and that the noise figure is fundamentally high because of the 1XN splitting loss.
lightreading article
I think the sequence goes something like this:
1) Transit to satellite: 120ms
2) Unknown delay: x
3) Transit to groundstation: 120ms
4) Some typical ping time on wired Internet (roundtrip from groundstation to ping site to groundstation): y
5) Transit to satellite: 120ms
6) Unknown delay: x
7) Transit to home: 120ms
Add it all up and we have 480ms + 2x + y. Seems to me that could easily be 900ms.
So, is anyone selling the Mann sunglass display or something equally discreet? If not, why not?
Most people I know would disagree strongly with this statement. I know that when I am talking with someone in person, I spend a great deal of time looking at that person's face to see reactions to what I am saying, or to draw some additional context out of what the person is saying. While it is possible to get some of that from the voice intonations when speaking on the phone, I know that I much prefer having conversations in person rather than on the phone because the visual cues add a lot to the conversation.
Here is an excellent website that has many in-depth reviews of digital cameras, including sample pictures:
http://www.imaging-resource.com/DIGCAM 01.HTM
They also review Kodak's Picture CD where you can take your standard print film to a regular film development house and for about $8-10 extra get back a CD with your pictures in addition to the prints. (resolution about 1.5K by 1K, but equivalent in quality to most 2Megapixel cameras)
Does the linux M15 build work with encryption? The M14 required a special build to work with crypto, and the crypto FAQ hasn't been updated in a while.
Oops, I had typed in the last sentence as an afterthought, but I just realized that the part about it not tilting was wrong. If the axis of rotation of the drum is horizontal, of course the drive would tilt if the forklift turned, just like a precessing gryoscope. Duh. So it must be that the drum drive had the platter mounted vertically (horizontal axis of rotation), since if it were mounted like a dinner plate, there would be no problem.
The trick about things with a lot of angular momentum is that they have a certain axis (vector) about which that angular momentum exists, and that AXIS resists rotation. Translating the axis but keeping it pointing in the same direction is easy.
One example of this is that if you were to make a flywheel-powered automobile, and you set the flywheel spinning with a vertical axis of rotation, then your car will be able to turn corners without difficulty but transitioning from a level road to a hill will be a disaster (incidentally, the solution is counter-rotating flywheels).
Before this gets even more off topic, the point is that the story about the drum drive either has some details wrong, or it is apocryphal. If the drum drive has a vertical angular momentum vector, than the forklift should have no troubles unless it tries to go up a ramp. If the drum is mounted with a horizontal rotation axis, then the forklift WOULD have difficulty turning, but the drive would NOT stand on one leg -- it would simply resist the turn, probably holding its orientation while the forklift turns underneath it (of course, it could fall off the edge of the forklift....)
The article doesn't say much about how it works. It sounds like it may be using the silicon micro-mirror technology developed by Texas Instruments where silicon is polished and etched into thousands of tiny, deflectable micro-mirrors, each one controlled by a transistor.
Anyone know if that's what they are using?