What I'd really like to see is one of these for cooling the CPU. I know there are heatpipe CPU coolers out there, but they all use fans. Making the video card cooler silent is great, but kind of pointless if you're still using a fan on the CPU.
It seems like the ideal solution would be a heatpipe system that dumped the heat directly to the case chassis, probably using an intermediate-stage heat spreader that could be bonded to the case. I've looked for such a thing, but never found one. Does anyone know of one?
I probably shouldn't even bite down on this, but I feel compelled to set the record straight:
If you had claimed to be "the principle designer of the XX rocket" or something along those lines, then it would mean something. As it stands, you're just another voice bagging from the sidelines.
I have done injector and combustion chamber design for rocket engines up to 2400 PSI chamber pressure. Furthermore, my designs were built and test-fired, which is something that few aerospace engineers under the age of fifty can claim.
Really, though, my qualifications are irrelevant to my original point, which was basically that they did not observe the KISS principle. Keep It Simple, Stupid is the first principle of good engineering design, regardless of the field in question.
As a aside, I think it will be really amusing when Carmack's small, low-funded venture beats XCor's well-funded mongolian-hoard venture to the X-Prize.:)
This is funny as hell to me. Xcor has done everything they have done (including the first privately-built rocket powered, piloted airplane) with something on the order of a million in funding over the last four years. They are the small, low-funded venture.
As far as I can tell from reading the report and looking at the video, this crash was not due to a computer failure.
It was due to a design failure.
The rocket appears to be unstable, which is to say that the center of gravity is behind the center of pressure. Looking at the pictures, it's not too surprising. The vehicle is too short vs. it's diameter, and the flared base isn't big enough to stabilize it (i.e. not big enough to push the Cp back behind the Cg of the vehicle).
I imagine that Carmack etc. knew that it was aerodynamically unstable and counted on active feedback controls to compensate, which was their primary mistake. By doing so, they greatly increased the critical complexity of the system, which is to say they increased the number of things that would kill the vehicle if any one of them failed.
It would have been far better to design for simplicity and graceful failure by building a vehicle that is aerodynamically stable. Someone forgot KISS.
I guess I shouldn't be surprised -- this is what happens when you let programmers design rockets.:)
I am using 90% H2o2 because using it as a monopropellant is the safest method of propulsion for my particular rocket. There is no chance of a catastrophic explosion or fire. This alone eliminates about one half of all standard problems that are encountered for any rocket flight./
This is just flat out bullshit. Peroxide works as a monopropellant because it has a positive heat of formation: When H2O2 breaks down into H2O and O2, it releases heat. The problem is that, at high concentrations, if the breakdown process starts, it can easily run away. Excessive heat or inappropriate contamination or just bad luck can start the process. It may not techincally be a "fire" but you aren't going to be able to tell the difference if you're sitting on it when it happens.
I don't know what is being referenced by "all the trouble with catalyst packs..." Peroxide reaction engines have been around for years, and follow specific scientific formulas.
Yes, peroxide rockets have been around for years. And in fact there is a well documented problem with the peroxide poisoning the catalyst bed. This isn't an issue if you don't care about reusability (and I doubt he does), but he obviously hasn't done much research if he hasn't at least encountered mention of this issue.
These days, no reputable environmental scientist is going to say that we're about to "run out of oil". What's probably going to happen instead is the scenario described by the peak oil hypothesis. Basically, there is a well known curve that describes how most wells produce (i.e. how hard/expensive it is to get to that oil). Generally the well is under pressure when you first tap it, so you get the first 50% or so very easily. After that, it becomes exponentially harder to get at the remaining oil. Very few wells really "run dry". Instead they become uneconomical to pump and get mothballed until the price of crude goes up enough to make them economical.
Even at our current rate of consumption, we're not going to run out of oil any time soon. But there is mounting evidence that most of our existing wells (both foreign and domestic) have passed their peak or will do so within the next 10-20 years. This is actually a good thing, IMO, because it means that rather than a catastrophic collapse of our oil-based economy, the oil will just start getting more and more expensive, which means that our economy will hopefully have time to adjust and roll out new technologies based on other energy sources.
But it's not going to be easy or painless, and a scenario like this will happen sooner or later -- you can't consume a finite resource forever -- so it behooves us to start thinking about the transition NOW, rather than while we're staring down the barrel of $5/gallon gasoline. (Sorry 'bout the pun. It wasn't intentional... at least not initially.)
Bear in mind that alot of computers that are collected for recycling wind up in some poor Asian country, where they create a horrible enviormental problem.
Well, I never claimed that 100 sq miles of solarcells would provide that much power. That was the previous poster. I probably should have checked his math, but I was lazy. Yeah, your de-rating figures are probably on the conservative side (which is to say, real world would probably be worse). Solar cells are not very efficient, which is why I don't really like them very much.
If I was going to a big centralized solar power plant, I'd go the solar-concentrator route anyway. It's cheaper, and the efficiency is comparable (and probably easier to improve than that of solar cells).
As to your other question, if you want to see some numbers, go pick up a copy of "Natural Capitalism". Or walk into any small-medium sized manufacturing outfit. Or store. Or almost any business. The waste is profligate, and it's all around you. Once you become aware of it, it's hard to stop seeing it. Eliminating it will require totally redesiging many of our established industrial processes, but the payback is enormous. The trick is convincing beancounters and businessmen that this is true.
Hell, we could reduce our energy demands by 20-40% just by switching to a distributed generation model -- the losses in those long-distance high tension lines are just sickening. And don't even get me started on the trucking industry. A variety of perverse incentives, combined with outmoded manufacturing models that place far too much faith in centralization, mean that it is not uncommon to, for example, grow garlic in California, ship it to Florida for processing, and then ship the jars of it back to California to sell them. And most of this shipping is happening by truck, which is 5x more power consumptive than freight train (freight trains don't have to stop as often, and when they do, they can accelerate and decelerate slowly, which makes a HUGE difference in energy use).
Would you like more examples? I can provide them. The low-hanging fruit is far from picked. We're just now becoming aware that that stuff we're bumping our heads on is fruit, and we should pick it.
All of the US's current electricity could be generated by a 10mi x 10 mi solar grid (100 square miles).*
While this may be true, I would not endorse this solution. Instead, consider that intelligent design with an eye towards efficiency could reduce our power consumption by 70-90% without compromising delivered value. Now you can do with with 1/4 to 1/10 of cells you used to need. That's where the real savings comes in.
Your point is well taken, that not all environmentalists apply their thinking evenly to their own ideas as they do to more traditional methods. However, it is equally true that there are relatively few opportunities for "green" technologies to externalize their costs, largely because they aren't well-established with long historical traditions and powerful lobbies to back them up. That's why they tend to cost so much.
Speaking to your particular points:
1) The bird kill problem is much reduced with the newer windmills, because they are HUGE (1-2 MW) and slower-turning, so the birds see them and avoid them.
2) I'll worry about the cost of covering large tracts of land with solar cells very shortly after we have got every south-facing roof, and every parking lot papered with solar cells (in sunny areas). I really don't think it's likely to be much of a problem. The toxic chemicals are more of a concern, but solar-cell manufacturers don't have the same privledge of dumping their polutants willy-nilly the way established oil and chemical companies tend to do. It would be better to eliminate those toxics from the process altogether, but as it stands their cost is at least included in the bottom line.
3) Wood is renewable, but is not sustainable as a power source for high population densities. And to hell with the CO2 impact of deforestation; worry instead about the release of previously-fixed carbon into the atmosphere (which is an issue with any hydrocarbon combustion, from wood to methane). Wood is a fine structural matieral (but hemp and bamboo are better for most things), but it's a lousy fuel.
We need to develop alternatives, but they need to be affordable alternatives.
Again, no arguement here, but think about what "affordable" means in this context. Does it mean, "must be able to compete with currently subsidized technologies" or does it mean "must be able to compete with established technologies on a level playing field". If you mean the former, then you ask far too much. If you mean the latter, then the answer is: They already do, where the field is in fact leveled.
Soory Greenies, that's the way it works. You want to save the enviroment, prove to someone with dollars that there is more dollars to be had and quickly.
Couldn't agree more. It's been done. Read Natural Capitalism by (among others) Amory Lovins.
Or, to paraphrase The Natural Step, every business, regardless of industry, produces only two things: Product, and non-product. Selling product makes money. Non-product is, at best, worthless and is frequently a liability.
The ratio varies by industry of course, but when you trace through the entire supply chain, usually only 5-10% of the materials stream winds up in product. Improving this figure is a huge opportunity to add money to the bottom line, and generally speaking, there is alot of room for improvement!
As far as the political process goes, the main thing the government needs to do is to:
1) Stop subsidizing waste.
2) Correct the legal structures that currently allow industries to externalze costs. Just to give a timely example, a gallon of gas would cost alot more than $1.50 if the oil companies had to foot, say, 25% of the nation's defense budget every year to preserve access to the oil (the ethical considerations notwithstanding, of course.) As it is, the taxpayers pick up the tab instead. A whole lot of "fringe" and "green" technologies would be much more in demand if the users of current technology had to pay the true costs of that technology.
And at $16 for.3 megapixels, this sounds like more of a novelty than a bargain, considering that 4-megapixel cameras are available now for less than a thousand dollars.
No they're not a substitute for one's personal primary camera. But they're excellent for two applications:
1) Taking pictures in places that put the camera at significant risk (hiking, rafting, Burning Man)
2) Handing out to lots of people -- i.e. weddings -- without spending a bunch of money.
Actually, I'm willing to concede the particular issue of email privacy, per se. As you suggest, unencrypted email is not secure to begin with. However, neither is it a part of the public record.
There are two elements of this issue that concern me very much:
1) Access to privately owned servers: In order to tap email, the authorities must tie in somewhere, probably at the ISP. I don't like the idea of the law being able to demand access to this informaiton without court approval via subpoena or warrent. First of all, it sets a bad precedent -- the information, while not inherently secure, resides on privately-owned servers to which the government should not automatically have the right of access. Secondly, it encourages "fishing expeditions", in which the law obtains and sorts through this information just because it can.
2) The assumption of access to electronic communications: Giving the law access to this information in this fashion implies, by its lack of checks and balances (i.e. court authorization), that the authorities have the right to see this information. If you extend this principle just a little further, you wind up with crypto key escrow and compulsory back doors. And such measures (which will be attempted, count on it) definately trod all over the right to privacy and the right to free communication.
Already did it. Here's a generic version of the letter I am writing. It is intentionally short and non-specific -- customize it to discuss the issues that concern you.
Dear XYZ,
Like you, I am aggrieved at the tragic loss of life resulting from the horrendous events of Sept. 11. Every American has been touched by this trauma which will linger forever in the memory of our nation.
Though I want to see the perpetrators of these acts brought to justice, I must beg you not to compromise American civil liberties in your pursuit of justice. The loss of American citizens' ability to move and communicate freely would be a greater casualty than the thousands killed Tuesday morning.
Benjamin Franklin said that those who give up necessary liberties for security deserve neither security nor freedom. I must echo his sentiment. Do not allow our sacred rights of freedom of speech, association or movement to be abridged in the coming days of difficult choices. America's enemies hate us precisely because we are a free and open society, and they fear the potential that that represents. Do not give them the victory they cannot themselves win by destroying the core of our society, our beloved liberties.
It has already begun. The "War on Terrorism" will supplant "saving the children" as a catchphrase to justify an increasing level of government control over daily life. It will start with an increase the interception of electronic communications and a new push for encryption key escrow. We could even see restrictions on movement and a mandatory national ID card. Don't doubt for an instant that law enforcement and government officials would like to see this happen -- because these things would in fact make their jobs easier. Whether or not these things come to pass is going to depend entirely on whether or not the public will tolerate it. If you care about your liberty, get ready to fight for it.
Write your congress(wo)men. Write the President. Get the address here, and use paper and a stamp, or at least make a phone call. Do it now. It's time to stand up and be counted, before the knee-jerk reaction to this disaster gains momentum.
I've included a generic version of the letter I am writing. It is intentionally short and non-specific -- customize it to discuss the issues that concern you.
Dear XYZ,
Like you, I am aggrieved at the tragic loss of life resulting from the horrendous events of Sept. 11. Every American has been touched by this trauma which will linger forever in the memory of our nation.
Though I want to see the perpetrators of these acts brought to justice, I must beg you not to compromise American civil liberties in your pursuit of justice. The loss of American citizens' ability to move and communicate freely would be a greater casualty than the thousands killed Tuesday morning.
Benjamin Franklin said that those who give up necessary liberties for security deserve neither security nor freedom. I must echo his sentiment. Do not allow our sacred rights of freedom of speech, association or movement to be abridged in the coming days of difficult choices. America's enemies hate us precisely because we are a free and open society, and they fear the potential that that represents. Do not give them the victory they cannot themselves win by destroying the core of our society, our beloved liberties.
There is a thing called a Glaser Safety Slug. It's basically a pistol bullet loaded with shot suspended in oil. Devastating against flesh, but it won't penetrate even wood: It's market is for people who want a gun for home defense, but don't want to risk having the bullet go through the wall and hit a neighbor
It's the George Orwell Principle: Pass so many laws that everyone, everywhere is a lawbreaker no matter what they do. Then you can arrest whoever you want to when it is convenient to do so.
(OK, I don't know if he was the one who said this first, but I first encountered this notion, stated more or less this way, in 1984.)
What we need is not smaller payments (micropayments) but bigger (or "chunkier") content. If I could pay $10-15/month to a central authority and know that I would have free reign to reload/. all day...
You have a good point, but consider this: What you describe sounds an awful lot like how the RIAA works, especially with regards to radio. As we all know, the guys that do the actual work see little of the money -- most of it goes to middlemen. It wouldn't necessarily have to happen this way, but it's always a danger when you introduce a middleman. Is this really what you want?
Slashdot Mirror
It seems like the ideal solution would be a heatpipe system that dumped the heat directly to the case chassis, probably using an intermediate-stage heat spreader that could be bonded to the case. I've looked for such a thing, but never found one. Does anyone know of one?
If you had claimed to be "the principle designer of the XX rocket" or something along those lines, then it would mean something. As it stands, you're just another voice bagging from the sidelines.
I have done injector and combustion chamber design for rocket engines up to 2400 PSI chamber pressure. Furthermore, my designs were built and test-fired, which is something that few aerospace engineers under the age of fifty can claim.
Really, though, my qualifications are irrelevant to my original point, which was basically that they did not observe the KISS principle. Keep It Simple, Stupid is the first principle of good engineering design, regardless of the field in question.
As a aside, I think it will be really amusing when Carmack's small, low-funded venture beats XCor's well-funded mongolian-hoard venture to the X-Prize.
This is funny as hell to me. Xcor has done everything they have done (including the first privately-built rocket powered, piloted airplane) with something on the order of a million in funding over the last four years. They are the small, low-funded venture.
Oh, and by the way, it's Caltech, not CalTech.
I'm not with Xcor any more.
It was due to a design failure.
The rocket appears to be unstable, which is to say that the center of gravity is behind the center of pressure. Looking at the pictures, it's not too surprising. The vehicle is too short vs. it's diameter, and the flared base isn't big enough to stabilize it (i.e. not big enough to push the Cp back behind the Cg of the vehicle).
I imagine that Carmack etc. knew that it was aerodynamically unstable and counted on active feedback controls to compensate, which was their primary mistake. By doing so, they greatly increased the critical complexity of the system, which is to say they increased the number of things that would kill the vehicle if any one of them failed.
It would have been far better to design for simplicity and graceful failure by building a vehicle that is aerodynamically stable. Someone forgot KISS.
I guess I shouldn't be surprised -- this is what happens when you let programmers design rockets.
This is just flat out bullshit. Peroxide works as a monopropellant because it has a positive heat of formation: When H2O2 breaks down into H2O and O2, it releases heat. The problem is that, at high concentrations, if the breakdown process starts, it can easily run away. Excessive heat or inappropriate contamination or just bad luck can start the process. It may not techincally be a "fire" but you aren't going to be able to tell the difference if you're sitting on it when it happens.
I don't know what is being referenced by "all the trouble with catalyst packs..." Peroxide reaction engines have been around for years, and follow specific scientific formulas.
Yes, peroxide rockets have been around for years. And in fact there is a well documented problem with the peroxide poisoning the catalyst bed. This isn't an issue if you don't care about reusability (and I doubt he does), but he obviously hasn't done much research if he hasn't at least encountered mention of this issue.
Even at our current rate of consumption, we're not going to run out of oil any time soon. But there is mounting evidence that most of our existing wells (both foreign and domestic) have passed their peak or will do so within the next 10-20 years. This is actually a good thing, IMO, because it means that rather than a catastrophic collapse of our oil-based economy, the oil will just start getting more and more expensive, which means that our economy will hopefully have time to adjust and roll out new technologies based on other energy sources.
But it's not going to be easy or painless, and a scenario like this will happen sooner or later -- you can't consume a finite resource forever -- so it behooves us to start thinking about the transition NOW, rather than while we're staring down the barrel of $5/gallon gasoline. (Sorry 'bout the pun. It wasn't intentional... at least not initially.)
If you're into his ideas, check out his book (just published) Cradle to Cradle
If I was going to a big centralized solar power plant, I'd go the solar-concentrator route anyway. It's cheaper, and the efficiency is comparable (and probably easier to improve than that of solar cells).
As to your other question, if you want to see some numbers, go pick up a copy of "Natural Capitalism". Or walk into any small-medium sized manufacturing outfit. Or store. Or almost any business. The waste is profligate, and it's all around you. Once you become aware of it, it's hard to stop seeing it. Eliminating it will require totally redesiging many of our established industrial processes, but the payback is enormous. The trick is convincing beancounters and businessmen that this is true.
Hell, we could reduce our energy demands by 20-40% just by switching to a distributed generation model -- the losses in those long-distance high tension lines are just sickening. And don't even get me started on the trucking industry. A variety of perverse incentives, combined with outmoded manufacturing models that place far too much faith in centralization, mean that it is not uncommon to, for example, grow garlic in California, ship it to Florida for processing, and then ship the jars of it back to California to sell them. And most of this shipping is happening by truck, which is 5x more power consumptive than freight train (freight trains don't have to stop as often, and when they do, they can accelerate and decelerate slowly, which makes a HUGE difference in energy use).
Would you like more examples? I can provide them. The low-hanging fruit is far from picked. We're just now becoming aware that that stuff we're bumping our heads on is fruit, and we should pick it.
While this may be true, I would not endorse this solution. Instead, consider that intelligent design with an eye towards efficiency could reduce our power consumption by 70-90% without compromising delivered value. Now you can do with with 1/4 to 1/10 of cells you used to need. That's where the real savings comes in.
Speaking to your particular points:
1) The bird kill problem is much reduced with the newer windmills, because they are HUGE (1-2 MW) and slower-turning, so the birds see them and avoid them.
2) I'll worry about the cost of covering large tracts of land with solar cells very shortly after we have got every south-facing roof, and every parking lot papered with solar cells (in sunny areas). I really don't think it's likely to be much of a problem. The toxic chemicals are more of a concern, but solar-cell manufacturers don't have the same privledge of dumping their polutants willy-nilly the way established oil and chemical companies tend to do. It would be better to eliminate those toxics from the process altogether, but as it stands their cost is at least included in the bottom line.
3) Wood is renewable, but is not sustainable as a power source for high population densities. And to hell with the CO2 impact of deforestation; worry instead about the release of previously-fixed carbon into the atmosphere (which is an issue with any hydrocarbon combustion, from wood to methane). Wood is a fine structural matieral (but hemp and bamboo are better for most things), but it's a lousy fuel.
We need to develop alternatives, but they need to be affordable alternatives.
Again, no arguement here, but think about what "affordable" means in this context. Does it mean, "must be able to compete with currently subsidized technologies" or does it mean "must be able to compete with established technologies on a level playing field". If you mean the former, then you ask far too much. If you mean the latter, then the answer is: They already do, where the field is in fact leveled.
Couldn't agree more. It's been done. Read Natural Capitalism by (among others) Amory Lovins.
Or, to paraphrase The Natural Step, every business, regardless of industry, produces only two things: Product, and non-product. Selling product makes money. Non-product is, at best, worthless and is frequently a liability.
The ratio varies by industry of course, but when you trace through the entire supply chain, usually only 5-10% of the materials stream winds up in product. Improving this figure is a huge opportunity to add money to the bottom line, and generally speaking, there is alot of room for improvement!
As far as the political process goes, the main thing the government needs to do is to:
1) Stop subsidizing waste.
2) Correct the legal structures that currently allow industries to externalze costs. Just to give a timely example, a gallon of gas would cost alot more than $1.50 if the oil companies had to foot, say, 25% of the nation's defense budget every year to preserve access to the oil (the ethical considerations notwithstanding, of course.) As it is, the taxpayers pick up the tab instead. A whole lot of "fringe" and "green" technologies would be much more in demand if the users of current technology had to pay the true costs of that technology.
No they're not a substitute for one's personal primary camera. But they're excellent for two applications:
1) Taking pictures in places that put the camera at significant risk (hiking, rafting, Burning Man)
2) Handing out to lots of people -- i.e. weddings -- without spending a bunch of money.
There are two elements of this issue that concern me very much:
1) Access to privately owned servers: In order to tap email, the authorities must tie in somewhere, probably at the ISP. I don't like the idea of the law being able to demand access to this informaiton without court approval via subpoena or warrent. First of all, it sets a bad precedent -- the information, while not inherently secure, resides on privately-owned servers to which the government should not automatically have the right of access. Secondly, it encourages "fishing expeditions", in which the law obtains and sorts through this information just because it can.
2) The assumption of access to electronic communications: Giving the law access to this information in this fashion implies, by its lack of checks and balances (i.e. court authorization), that the authorities have the right to see this information. If you extend this principle just a little further, you wind up with crypto key escrow and compulsory back doors. And such measures (which will be attempted, count on it) definately trod all over the right to privacy and the right to free communication.
Dear XYZ,
Like you, I am aggrieved at the tragic loss of life resulting from the horrendous events of Sept. 11. Every American has been touched by this trauma which will linger forever in the memory of our nation.
Though I want to see the perpetrators of these acts brought to justice, I must beg you not to compromise American civil liberties in your pursuit of justice. The loss of American citizens' ability to move and communicate freely would be a greater casualty than the thousands killed Tuesday morning.
Benjamin Franklin said that those who give up necessary liberties for security deserve neither security nor freedom. I must echo his sentiment. Do not allow our sacred rights of freedom of speech, association or movement to be abridged in the coming days of difficult choices. America's enemies hate us precisely because we are a free and open society, and they fear the potential that that represents. Do not give them the victory they cannot themselves win by destroying the core of our society, our beloved liberties.
God Bless America,
Write your congress(wo)men. Write the President. Get the address here, and use paper and a stamp, or at least make a phone call. Do it now. It's time to stand up and be counted, before the knee-jerk reaction to this disaster gains momentum.
I've included a generic version of the letter I am writing. It is intentionally short and non-specific -- customize it to discuss the issues that concern you.
Dear XYZ,
Like you, I am aggrieved at the tragic loss of life resulting from the horrendous events of Sept. 11. Every American has been touched by this trauma which will linger forever in the memory of our nation.
Though I want to see the perpetrators of these acts brought to justice, I must beg you not to compromise American civil liberties in your pursuit of justice. The loss of American citizens' ability to move and communicate freely would be a greater casualty than the thousands killed Tuesday morning.
Benjamin Franklin said that those who give up necessary liberties for security deserve neither security nor freedom. I must echo his sentiment. Do not allow our sacred rights of freedom of speech, association or movement to be abridged in the coming days of difficult choices. America's enemies hate us precisely because we are a free and open society, and they fear the potential that that represents. Do not give them the victory they cannot themselves win by destroying the core of our society, our beloved liberties.
God Bless America,
There is a thing called a Glaser Safety Slug. It's basically a pistol bullet loaded with shot suspended in oil. Devastating against flesh, but it won't penetrate even wood: It's market is for people who want a gun for home defense, but don't want to risk having the bullet go through the wall and hit a neighbor
Silly frosh! Grad turkeys don't live in the houses, although I suppose he might have been a social member.
(OK, I don't know if he was the one who said this first, but I first encountered this notion, stated more or less this way, in 1984.)
Need I say more?
You have a good point, but consider this: What you describe sounds an awful lot like how the RIAA works, especially with regards to radio. As we all know, the guys that do the actual work see little of the money -- most of it goes to middlemen. It wouldn't necessarily have to happen this way, but it's always a danger when you introduce a middleman. Is this really what you want?