Most people don't know it's available for free today. This is because open-source software on the store shelves is a relatively new phenomenon; the ignorance won't last. Tomorrow is going to be a new ballgame.
You think so? I think he'll buy whichever box he wants the support from (assuming he knows what he's doing). That's all that's really being sold here, folks: support. All the GPL'ed code is available for the cost of copying it.
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it would be neat if the energy generated by walking and breathing could be used to power the wearable.
That seems easy enough, but you'd have to get used to having your clothing tight so that it could pull against your movements. Especially in warm places like SoCal, I could see this being unpopular. The alternative would be to have spandex-like clothes, which might be unsightly for many geeks.
I have given some thought to powering a laptop from muscle motion, and I concluded that reflexively bouncing your knee up and down (with your toe on the floor) could be tapped to generate enough power to run a modest computer. This does, however, makes it difficult to put a laptop on top of your lap. As long as you're walking around it would be trivial to generate some tens or hundreds of milliwatts from the flexing of the soles of your shoes; I put over a kilonewton of force on my foot when I step down, and 5 mm of motion is 5 joules right there. I don't see similar possibilities from breathing.
The 'small efficient government' that you fantasize of only ruled 13 colonies and probably less than 100,000 people (anyone know an actual number here?).
According to the miscellaneous commentary about Paine's pamphlet "Common Sense" which I found here is a statement that the population of the 13 colonies in 1776 was about 1.5 million. You're off by about 12 dB; that's a hell of a lot, dude.
I never said other outlets weren't subject to the same kind of thing; however, even/. hasn't raised a serious objection to the second Mindcraft "benchmark" test results which showed that NT is faster than Red Hat Linux on a certain hardware platform and serving a certain mix of clients (emphasis for flame-proofing). However, while there was the predictable amount of juvenile flaming, the saner posts (and generally, the ones upgraded by the moderators, who stand in for editors) made the point that the results were not relevant to the real world. In other words, they counted for little or nothing.
And that, my friend, is a lesson the editors of Social Text should have learned in school.
Re:Ignorant of the implications
on
Linux on a SIMM
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· Score: 1
if you're a terrorist you can use a ruggadized version of this SIM as your embedded controller for simple "smart" RPG's,or a crude cruise missles system, etc.
This doesn't do anything that a PC-104 system wouldn't do, and you can certainly get more power in an x86-based system.
hack this together with a GPS system
Civilian (non-aircraft) GPS has about a 250 MPH "speed limit" built into it; it won't maintain lock over that speed. Makes it hard to navigate missiles with it.
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many take the phrase about the right to life, liberty, and the pursuit of happiness to mean that nothing can stop us from being happy...
The phrase "Life, liberty, and the pursuit of happiness" appears nowhere in the Constitution of the USA. It is from the Declaration of Independence, which is polemic and has no relation to the laws of the United States.
Realize that it is your duty to NEVER convict a person that has broken an un-Constitutional law...
Unfortunately, by the time a case gets to a jury the defendant is probably ruined already; between the costs of defense and the lost time out of their life, the prosecution can destroy a person even with a case that will never get a guilty verdict. Look at the obvious abuses of denial of bail if you disagree.
Between the fights over abortion, evolution, guns, speech and everything else, this country is likely to fragment into a bunch of warring factions. The only way we are going to survive is to return to an ethos of "life and let live"; going back to a government of strictly limited powers is the only way to preserve a Republic.
I remember Sokal's paper. It was hilarious. And it did an excellent job of proving that the editors (and readers?) of Social Text have no critical-reasoning facilities whatsoever; they will publish or agree with anything that appears to support their preordained conclusions (and given the current fad in leftie circles that logic and evidence [let alone peer-review] are politically incorrect, one would not expect anything better). By doing so, and given Social Text's position at the top of the heap, Sokal single-handedly demonstrated the irrelevance of "lit crit" to anything outside of itself; like a black hole, nothing of use ever comes out. It's time for universities to de-fund the departments which tenure these clowns; they're an embarrassment to our entire nation.
One can legitimately knock Katz for being sloppy. For instance, he didn't bother to save this article without those annoying smart quotes, and he left a number of grammatical errors in it. (Basically, he needs a copy editor.)
On the other hand, I don't see anyone else doing what he does for the/. community. If it weren't for him, we wouldn't have this kind of commentary at all. And that's telling, isn't it?
Almost certainly measurement error. Compensating for sticktion on something which is vibrating from nearby rotating machinery is a very tricky business.
Last I heard, the current research on it was at the point where to raise a 1/2 ton object to 20,000 ft would require (if it could be built, which isn't possible yet, so this is simple scaling) a $40 billion (to construct) laser
Since this is a "simple scaling", please say where you got the figure of $40 million/pound lift from.
costing $3billion/second to operate about 4 minutes
Let's analyze this number a bit, shall we? Electricity is one of the most expensive forms of energy on the planet, so let's assume it's using that. $3 billion a second at ten cents US per KWH is 30 billion KWH/second, or 36 trillion watts. This is about ten times the total electric generating capacity of the USA. This number is clearly ridiculous.
Let's work backwards from the thrust requirements. Pushing 1000 pounds at 2 G's would get it to 20,000 feet (fighting 1 G of gravity) in 35.2 seconds (not 4 minutes). If the propulsion system had an impulse of 5000 seconds, it would consume 0.4 lbm propellant/sec to produce those 2000 pounds of thrust. The minimal energy requirements are thus (0.4 lbm/sec / 2.205 lbm/kg ) * (5000 * 9.81)^2 / 2 = 218 megawatts. If the propulsion loses 50% of the laser pulse and the laser is 10% efficient, the power requirement is 4.36 GW. This is about 1/10000 of the number we get from Rift's figures. At $.10/KWH, consuming 4.36 GW for 4 minutes costs about $29,000. It would take somewhat longer (or greater acceleration) to put that load into orbit, but that's not bad for flying half a ton, eh?
Building a system to lift 20 pound payloads instead of half-ton payloads cuts the numbers by a factor of 50, to about 90 megawatts electric. 20 pounds is a bunch of MRE's, a day's worth of fresh water, or enough H2/O2 to launch more than its mass from LEO to the moon. It's not much of a spacecraft, but 20 pounds could easily be the extrusion dies to make the aluminum frame from pellets (also shipped 20 pounds at a time) or an entire module of the ship's electronics.
Space Shuttle is a Conestoga wagon; HELL is a pipeline. Guess which is cheaper for moving real quantitites of anything?
It's been a dream for years. Every kid who grew up watching Fireball XL-5 in the 60's would agree with you.
There are some drawbacks to the idea. Mostly, going up the side of a mountain means that you have to launch from a mountain range. Usually you have populated areas to the east, and launching over them has been taboo in NASA circles. (Why do you think all the polar launches are done southward from Vandenberg, and the eastward launches are done from Canaveral? It's because the flight path covers nothing but water for thousands of miles.)
On top of the risks and the cost of buying a whole new launch site, you lose some flexibility of launch azimuth (choosing your orbital plane). This shortens your launch windows, assuming that you have them at all. This is a high price to pay for shaving 200 MPH off your delta-V requirements. It might be worth it if you had enough volume to move into a particular orbit, but laser launchers will almost certainly be more cost-effective and more flexible for bulk materials and avoid all of the safety hassles.
I can see it now: All it is able to lift is a little toy. Basically useless.
Depends what you're trying to lift. A lot of what goes into orbit, even today, amounts to bulk commodities (water, rocket fuel, even food and air). You can easily divide that sort of thing into lots of 10-pound packages and ship them up by the thousands. The laser power limits how much you can lift at once, but you forget: you can launch a new payload every few minutes! You can only put a few pounds of stuff on one foot of a conveyor belt, but that conveyor belt can move a whopping amount of material each day.
If your costs fall from $10,000/pound to $50/pound for the bulk stuff, it suddenly becomes a hell of a lot cheaper to do anything in LEO that involves long-term human presence, for example. The same laser system would also be very useful for knocking space junk out of orbit. It makes too much sense not to spend effort on it.
Not that NASA will spend money on anything that threatens Shuttle and its budget, but it should still be done.
Unfortunately, the linear aerospike engine is a boondoggle. It's not necessary, it's just a way of squeezing more R&D money out of the taxpayer.
If Goldin and NASA were really interested in applying "Better, faster, cheaper" to the basic business of earth-to-LEO transport, they would have continued the DC-1 development effort. The atmospheric test vehicle, the DC-X, was a phenomenal success. It proved that all the required low-speed maneuvers, including a reversal in flight and a powered landing, could be done with current technology. And it was all done on a shoestring budget.
Unfortunately for the US taxpayer, the DC-X was built by SDIO, not NASA. SDIO is not in the transport business, so the DC-X was transferred to NASA. On the final flight of the test series, a landing-gear unlock hose was left disconnected. As a result one gear leg did not deploy, the craft fell over after landing, and it caught fire and burned. The pre-flight checklists did not call for the line to be checked before takeoff; now whose fault is that, do you think?
After DC-X's destruction, the DC-1 program (which was slated to have a full-scale transport in operation around now) was shelved. Instead, Goldin announced the VentureStar program (with its fancy linear aerospike engine). VentureStar will take billions in development contracts and will not replace the Shuttle (and its standing army of maintenance people) for many years. The aerospace development lobby's stream of money was protected.
Sorry, you are wrong. There is a line of hybrid motors (made by Hypertek, IIRC) built just for rocket hobbyists.
You will not find them at your local hobby store. Blister-pack motors run about 1/4 A through D ratings. (Each letter designation is twice the total impulse of the one before; a B motor is equivalent to two A motors, a C to two Bs, etc.). The Hypertek is a J (about 64 times as powerful as a D), and is only sold to people with membership in the appropriate high-power rocket groups.
You're half-right. It's the chlorine in the SRB fuel (from the perchlorate oxidizer) which makes it a possible ozone-depleter, so getting rid of it by going to a chlorine-free fuel and liquid oxygen for the oxidizer pretty much eliminates the issue for the SRB's. You can still form a little NOx (another ozone depleter) by applying heat to the outside air, but the temperature, pressure and time are all too low to get much conversion.
Where you're wrong is in thinking that the "environuts" will stop. Take the Cassini "controversy" as an example. The nutcakes were trying to get the Earth flyby banned on the minuscule chance that the probe could hit us and spill plutonium and poison people. They maintain this paranoid scenario despite confirmed facts:
The probe would have to have been at least 600 miles off-course to hit Earth, and JPL's guidance capabilities are such that they can hit a 1-mile wide window at Saturn (literally a billion miles away).
Any guidance error big enough to hit Earth would be many times larger than the error which would put the probe on an track which would never get to Saturn; we'd lose the mission long before it could possibly hit Earth.
RTG's have hit Earth before (Apollo 13's LEM carried two), and we never detected any plutonium from them. As far as we can tell they are sitting on the bottom of the Pacific, containment shells intact.
Above-ground testing in the 40's and 50's released tons of Pu-239 into the atmosphere (half-life: 24,000 years). Cassini carries about 70 pounds of Pu-238 (half-life: 89 years). Even if it did get loose, could anyone tell?
So no, the environuts will always be squawking about something. They'll keep squawking until the news media stop irresponsibly "reporting" their BS without rebuttal, and start providing analysis and facts which show the difference between their FUD and the truth. That requires reporters and editors with an education in science and willing to put truth before controversy. And we all know how likely that is, don't we?
If you bothered to read the commentary in the exchange of letters, you would have found this statment from Dell: "Dell Servers can be shipped without an OS". You have said nothing new.
That aside, it does not mean that purchasers of Dell workstations have any meaningful choice.
Aspartame-->MeOH is why anyone who regularly consumes this artificial sweetener is an absolute moron and deserves all the neurological-related health problems they will certainly get when they grow old.
Obviously you haven't bothered reading the source. A quote:
Aspartame is composed of two amino acids, aspartic acid and the methyl ester of phenylalanine. Aspartame is completely and quickly metabolized to its two amino acids (aspartic acid and phenylalanine) and methanol through normal pathways. Amino acids are building blocks of protein. The body treats aspartame the same way it handles other foods, such as bananas, milk and hamburgers. The methanol is identical to that which we consume in much larger concentrations in fruits, vegetables and their juices, for instance. It is part of the normal diet.
The amount of methanol produced is approximately 10% by weight. The body then converts methanol to formaldehyde and then to a metabolite called formate. Formate is then quickly eliminated by the body in the form of carbon dioxide and water. Some critics point out that methanol, an alcohol, is toxic. However, the amounts produced in metabolism are small, and are no greater than the methanol produced by the metabolism of many fruits and vegetables. For comparison's sake, the amount of methanol resulting from drinking a 12-ounce can of soda sweetened with aspartame is less than obtained from drinking an 8-ounce glass of grape juice.
I assume that this means you've already given up grape juice, since you are so well-informed on this matter. (Basically, anyone who believes unconfirmed bullshit posted by Anonymous Cowards deserves what they get.)
I can confidently predict that if it's rechargable, it'll quietly wither and die. There's too much income at stake from disposables for this to become the dominant player.
You're assuming two things:
That the battery companies will all maintain ranks to preserve the market for disposables (instead of trying to grow the market for batteries, or just plain cutting into the market for the other guy's product), and
That no company outside the disposable-battery market would enter the rechargeable market to take advantage of the unserved need.
As counter-examples, look at the way long-lasting radial tires got rid of bias-ply tires to the ultimate detriment of the tire companies, and recall that dozens of microcomputer companies sprang up to sell devices that mainframe and mini manufacturers did not think were worthwhile. This is all recent history.
The upshot is, if these things work well and provide good value, they'll sell like mad and make lots of money for the company that sells 'em.
But our predecessors were smart cookies. There's a reason why we have lead-acid... cheap, dependable, doesn't freeze at 32 degrees, etc...
Just FYI, these are alkaline batteries we're talking about here. They use a hydroxide electrolyte, and give you similar freezing-point depression to acid electrolytes. (Or did you think there wasn't any water in the H2SO4 in your car's battery?)
Some compounds of carbon, nitrogen and hydrogen can be very toxic (like HCN). Ditto carbon, hydrogen and oxygen (like formaldehyde, CH2O). The toxicity of a compound does not necessarily have anything to do with the toxicity of the elements of which it is composed.
While I'm aware of nickel being somewhat toxic as well as allergenic to some people, iron is an essential nutrient. People work with iron rust all the time and do not get toxic reactions. This ferrate battery is going to be about as safe as you can possibly get.
Gerald Bull. In this case, the cypherpunks aren't going up against the Mossad (Israeli security agency), and killing any of them is probably going to backfire rather badly.
The only threat to "national security" is that the administration won't be able to use wiretapping to get the jump on their political opposition any more. Thank goodness, we may finally exorcise the ghost of the Nixon administration.
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Most people don't know it's available for free today. This is because open-source software on the store shelves is a relatively new phenomenon; the ignorance won't last. Tomorrow is going to be a new ballgame.
You think so? I think he'll buy whichever box he wants the support from (assuming he knows what he's doing). That's all that's really being sold here, folks: support. All the GPL'ed code is available for the cost of copying it.
I have given some thought to powering a laptop from muscle motion, and I concluded that reflexively bouncing your knee up and down (with your toe on the floor) could be tapped to generate enough power to run a modest computer. This does, however, makes it difficult to put a laptop on top of your lap. As long as you're walking around it would be trivial to generate some tens or hundreds of milliwatts from the flexing of the soles of your shoes; I put over a kilonewton of force on my foot when I step down, and 5 mm of motion is 5 joules right there. I don't see similar possibilities from breathing.
And that, my friend, is a lesson the editors of Social Text should have learned in school.
Between the fights over abortion, evolution, guns, speech and everything else, this country is likely to fragment into a bunch of warring factions. The only way we are going to survive is to return to an ethos of "life and let live"; going back to a government of strictly limited powers is the only way to preserve a Republic.
For those interested in the whole affair, look up the paper's title in Altavista. Here's some of Sokal's commentary on the spoof.
On the other hand, I don't see anyone else doing what he does for the /. community. If it weren't for him, we wouldn't have this kind of commentary at all. And that's telling, isn't it?
Almost certainly measurement error. Compensating for sticktion on something which is vibrating from nearby rotating machinery is a very tricky business.
Let's work backwards from the thrust requirements. Pushing 1000 pounds at 2 G's would get it to 20,000 feet (fighting 1 G of gravity) in 35.2 seconds (not 4 minutes). If the propulsion system had an impulse of 5000 seconds, it would consume 0.4 lbm propellant/sec to produce those 2000 pounds of thrust. The minimal energy requirements are thus (0.4 lbm/sec / 2.205 lbm/kg ) * (5000 * 9.81)^2 / 2 = 218 megawatts. If the propulsion loses 50% of the laser pulse and the laser is 10% efficient, the power requirement is 4.36 GW. This is about 1/10000 of the number we get from Rift's figures. At $.10/KWH, consuming 4.36 GW for 4 minutes costs about $29,000. It would take somewhat longer (or greater acceleration) to put that load into orbit, but that's not bad for flying half a ton, eh?
Building a system to lift 20 pound payloads instead of half-ton payloads cuts the numbers by a factor of 50, to about 90 megawatts electric. 20 pounds is a bunch of MRE's, a day's worth of fresh water, or enough H2/O2 to launch more than its mass from LEO to the moon. It's not much of a spacecraft, but 20 pounds could easily be the extrusion dies to make the aluminum frame from pellets (also shipped 20 pounds at a time) or an entire module of the ship's electronics.
Space Shuttle is a Conestoga wagon; HELL is a pipeline. Guess which is cheaper for moving real quantitites of anything?
There are some drawbacks to the idea. Mostly, going up the side of a mountain means that you have to launch from a mountain range. Usually you have populated areas to the east, and launching over them has been taboo in NASA circles. (Why do you think all the polar launches are done southward from Vandenberg, and the eastward launches are done from Canaveral? It's because the flight path covers nothing but water for thousands of miles.)
On top of the risks and the cost of buying a whole new launch site, you lose some flexibility of launch azimuth (choosing your orbital plane). This shortens your launch windows, assuming that you have them at all. This is a high price to pay for shaving 200 MPH off your delta-V requirements. It might be worth it if you had enough volume to move into a particular orbit, but laser launchers will almost certainly be more cost-effective and more flexible for bulk materials and avoid all of the safety hassles.
If your costs fall from $10,000/pound to $50/pound for the bulk stuff, it suddenly becomes a hell of a lot cheaper to do anything in LEO that involves long-term human presence, for example. The same laser system would also be very useful for knocking space junk out of orbit. It makes too much sense not to spend effort on it.
Not that NASA will spend money on anything that threatens Shuttle and its budget, but it should still be done.
If Goldin and NASA were really interested in applying "Better, faster, cheaper" to the basic business of earth-to-LEO transport, they would have continued the DC-1 development effort. The atmospheric test vehicle, the DC-X, was a phenomenal success. It proved that all the required low-speed maneuvers, including a reversal in flight and a powered landing, could be done with current technology. And it was all done on a shoestring budget.
Unfortunately for the US taxpayer, the DC-X was built by SDIO, not NASA. SDIO is not in the transport business, so the DC-X was transferred to NASA. On the final flight of the test series, a landing-gear unlock hose was left disconnected. As a result one gear leg did not deploy, the craft fell over after landing, and it caught fire and burned. The pre-flight checklists did not call for the line to be checked before takeoff; now whose fault is that, do you think?
After DC-X's destruction, the DC-1 program (which was slated to have a full-scale transport in operation around now) was shelved. Instead, Goldin announced the VentureStar program (with its fancy linear aerospike engine). VentureStar will take billions in development contracts and will not replace the Shuttle (and its standing army of maintenance people) for many years. The aerospace development lobby's stream of money was protected.
Not a very good deal for us, I think.
You will not find them at your local hobby store. Blister-pack motors run about 1/4 A through D ratings. (Each letter designation is twice the total impulse of the one before; a B motor is equivalent to two A motors, a C to two Bs, etc.). The Hypertek is a J (about 64 times as powerful as a D), and is only sold to people with membership in the appropriate high-power rocket groups.
Where you're wrong is in thinking that the "environuts" will stop. Take the Cassini "controversy" as an example. The nutcakes were trying to get the Earth flyby banned on the minuscule chance that the probe could hit us and spill plutonium and poison people. They maintain this paranoid scenario despite confirmed facts:
- The probe would have to have been at least 600 miles off-course to hit Earth, and JPL's guidance capabilities are such that they can hit a 1-mile wide window at Saturn (literally a billion miles away).
- Any guidance error big enough to hit Earth would be many times larger than the error which would put the probe on an track which would never get to Saturn; we'd lose the mission long before it could possibly hit Earth.
- RTG's have hit Earth before (Apollo 13's LEM carried two), and we never detected any plutonium from them. As far as we can tell they are sitting on the bottom of the Pacific, containment shells intact.
- Above-ground testing in the 40's and 50's released tons of Pu-239 into the atmosphere (half-life: 24,000 years). Cassini carries about 70 pounds of Pu-238 (half-life: 89 years). Even if it did get loose, could anyone tell?
So no, the environuts will always be squawking about something. They'll keep squawking until the news media stop irresponsibly "reporting" their BS without rebuttal, and start providing analysis and facts which show the difference between their FUD and the truth. That requires reporters and editors with an education in science and willing to put truth before controversy. And we all know how likely that is, don't we?Perhaps. Still, Linux is a better service pack. ;-)
That aside, it does not mean that purchasers of Dell workstations have any meaningful choice.
4.3 billion years = 1.36e20 milliseconds. I don't know where you got the other 7 orders of magnitude from.
- That the battery companies will all maintain ranks to preserve the market for disposables (instead of trying to grow the market for batteries, or just plain cutting into the market for the other guy's product), and
- That no company outside the disposable-battery market would enter the rechargeable market to take advantage of the unserved need.
As counter-examples, look at the way long-lasting radial tires got rid of bias-ply tires to the ultimate detriment of the tire companies, and recall that dozens of microcomputer companies sprang up to sell devices that mainframe and mini manufacturers did not think were worthwhile. This is all recent history.The upshot is, if these things work well and provide good value, they'll sell like mad and make lots of money for the company that sells 'em.
While I'm aware of nickel being somewhat toxic as well as allergenic to some people, iron is an essential nutrient. People work with iron rust all the time and do not get toxic reactions. This ferrate battery is going to be about as safe as you can possibly get.
The only threat to "national security" is that the administration won't be able to use wiretapping to get the jump on their political opposition any more. Thank goodness, we may finally exorcise the ghost of the Nixon administration.