It seems that the failure to apply the thermodynamic limitations to radiation physics has shown up in many experiments involving radiation pressure. Thus Crookes' radiometer has invariably rotated in the opposite sense to the expected one. The black side of the paddles invariably recedes from the light, and many explanations have been offered, but not including that which would seem the most obvious: the absence of radiation pressure on the bright side. Similarly all attempts to observe a steady deflection of a pendulum exposed to a light beam have always only shown a brief effect following the sudden beginning of the illumination. Experimental evidence has been ignored and "explained away" each time as some unexpected artifact, because of the widespread belief that the conventional momentum conservation law must be correct. But this law was recognized by Newton only for material bodies, and he had no information about radiation effects. But the momentum conservation law can be shown not to apply to the interaction of radiation with any material objects.
But he does not know how a radiometer works. It does not in fact work by radiation pressure but by gas pressure being higher against the heated side. It won't work at all if there is a hard vacuum in the bulb, there has to be only a partial vacuum. See this description or this one.
I also note that it is common to see people who have to control spacecraft (especially those not in earth orbit) say that you cannot neglect the effects of solar radiation pressure on the spacecraft's attitude and trajectory. For example NASA's Microwave Anisotropy Probe plans to use solar radiation pressure for backup attitude control (see page 8) and at the very least, cannot neglect this force on the spacecraft.
I would tend to conclude that this guy doesn't really know what he's talking about.
I assume they must be crowing about the software architecture because IA64 is about as closed as you can get. Intel/HP have patents that will pretty much prevent anyone else from cloning it (assuming anyone would want to).
But if they are talking about the software on the machine, why the emphasis on HP? Did HP fund the IA64 linux port? Perhaps they are referring to HP's willingness to sell a big pile of boxes with Linux as the operating system.
Do you seriously think that Microsoft is capable of producing a system that has tight enough security to prevent somebody from breaking their DRM scheme? If they released such a thing, within a week someone will discover that a buffer-overrun bug in drm.dll or some such thing lets you hack the DRM scheme to disable it or bypass it.
Wrong. Anybody can buy a reader for the OBD-II interface that is on 1996 and newer cars or more importantly build your own if you like.
You can get the SAE document describing the interface for $80 or so (or you can do what I did and borrow it from a university library). Companies such as multiplex engineering and others sell interface blocks that convert the oddball OBD-II electrical interface on your car to RS-232 serial. Then you are free to write your own diagnostic software for your linux laptop. Most of the trouble codes are standardized but if you want more info get your car's service manual from HELM or some other source.
Of course I'd be remiss if I didn't point out that the automotive aftermarket industry (i.e. repair shops) fought to make sure that you could do these things. And it seems like some fraction of car dealers have always been run by crooks (or idiots).
From a search of local libraries it looks like Baen Books also reprinted The Broken Sword in 1988.
If you can't find a copy of an older book to buy, check with your local library. You can usually do a multi-library search from a web site and then email a request for inter-library loan. For instance there are two copies of The Broken Sword in Minnesota libraries, one is the 1971 Ballentine (w/ intro by Lin Carter) and the other is the 1988 Baen edition.
Some researchers at the university of minnesota put together something called the "PowerWall" for Supercomputing '94. It was an array of 4 1600x1200 projectors combined on a single 8'x6' screen for 3200x2400 resolution. There were two SGI Onyx machines with Reality Engine graphics, each driving two of the screens. In addition we had a big stack of RAID 3 disk arrays (Ciprico) so we had enough bandwidth through the system to stream 24 bit/pixel images at full resolution at 20-30 frames/second. The cool thing was that if you stand next to the screen it fills your whole peripheral vision. I tried a couple of times but could never quite get glquake to work on it.
On the subject of triethyl borane, there is a very interesting book on the development of boron based fuels intended for the B-70 bomber: The green flame: surviving government secrecy by Andrew Dequasie. In order for the B-70 to have useful range at mach 3, more energy density was needed than hydrocarbon based fuels could provide, which led to research in various borane compounds. Unfortunately these compounds are extremely dangerous to work with (as the previous poster indicates) and the combustion products include boric oxide (boiling point 1860 C) which tends to solidify on the turbine blades of a turbojet. The project was cancelled along with the XB-70.
A correction and a comment... RS64-IV (aka IStar) has a 4 stage pipe, not 5. Also notable is that due to the short pipe, there is no branch penalty in most cases. This processor also has HMT (hardware multithreading). It only executes one thread at a time, but can switch threads on cache misses or other long latency events.
There are no big surprises here. NASA continues to try to build the most technically advanced craft possible, instead of actually building something that works. For a detailed description of how NASA screwed up and why X-33 is dead (written a year ago) see: http://www.space-access.org/updates/sau91.html
The real problem here is that NASA has become an enormous entrenched bureaucracy. They aren't interested in any solution that doesn't require an army of 10,000 engineers and technicians because then they won't be able to justify an legion of bureaucrats. The DC-X craft was built and tested on a shoestring over the objections of NASA. A scaled up SSTO based on that would require a support staff on the same order as a 747 (hundreds of people rather than tens of thousands as is the case for the shuttle) and would fly daily to weekly. For a detailed description of how we could have built such a craft as early as the '70s, see Halfway to Anywhere: achieving America's destiny in space by G. Harry Stine.
Another problem we have run into along the way here is that NASA has done everything it can to squash the independent, privately funded space transportation startups (Rotary Rocket, Beal, Kistler, etc.). NASA administrator Dan Goldin has made disparaging (and untrue) statements about their technologies which have contributed to their funding difficulties. In addition NASA continues to propose initiatives that would compete against these companies.
I still think NASA's planetary/space science programs (Pioneer/Voyager/Galileo/Cassini/etc.) are something to be proud of, but they have had to take a back seat to the "shuttle-station complex" (sing to the tune of "military-industrial complex") and that really disgusts me. What can you do about it?
Don't reply to this post! Instead, write, call, fax, or email your congresscritters (all 3 of them) and demand that we get NASA out of the launch vehicle development business.
If you think you can dump water on liquid sodium without a catastrophic hydrogen explosion, you've got another think coming. 2 Na + 2 H2O = 2 NaOH + H2 + a bunch of heat energy (which usually ignites the released H2 if O2 is present). This is why sodium metal is usually stored in some kind of oil (to prevent contact with water). A high-school chemistry prank I have heard of is to flush a chunk of sodium metal in a toilet. Sometimes, the toilet is even destroyed by the resulting hydrogen explosion in the sewer pipe.
Lots of people are saying that X is too bloated to ever work on a handheld. Well, in the late 80's I admin'd a Sequent S27, which had 4 processors (16MHz 80386's) and 16MB of memory running "Dynix" which was a 4.?BSD based UNIX. We had 4 Visual x-terminals and about a dozen serial terminals running off this thing. The users were running vi, tex, xdvi, ghostview, and emacs.
I think strongARM based handhelds like the iPAQ probably exceed this machine's capabilities in every category except i/o (it had multiple SMD disk interfaces, SCSI, and a VME bus for slow stuff, if I recall correctly). I don't see why X wouldn't work quite nicely on the iPAQ if you had an appropriate toolkit that worked well with the 320x200 screen resolution.
There's no doubt that domestic pushrod engines can survive more abuse... a friend had a '79 Nova with the straight-6, it ran dry of oil at least twice and still ran reasonably well the last time I saw it at about 120000 miles.
As far as the mitsubishi 3.0 V6 goes, I have another friend with a plymouth acclaim that has one of these; yes, it leaks oil from every available orifice. Good thing it's a non-intereference engine because he's got over 160000 miles on it and hasn't changed the timing belt.
My personal preference (maybe it's an acquired taste) is to drive something smaller and lighter with an engine that likes to rev. I've had fun driving, maintaining (I do all my own work), and tuning my CRX for 12 years. I'm guessing from your email address that your preferences lie elsewhere....
I agree with what you're saying up to the point of saying that a civic will only last 120,000 miles. This may be true if the body totally rusts out. Thin sheet metal suffers badly from rust, as you say. But well maintained honda engines will last a lot longer than that. My '88 CRX Si has 196000 miles, uses no oil, gets 38mpg, and is still as fast as it was when it was new. (but yes, you do have to remove the left axle to replace the alternator )-: ). My '86 accord I bought a year ago with 220000 miles and now has 242000 miles. Similar story with that one; no oil consumption, 32mpg.
To get back to the topic, I'm waiting for the 2002 Civics, which are rumored to have an option for a hybrid gas/electric engine system similar to that used in the Insight.
DC-X tipped and burned because one of the landing legs did not deploy (stayed folded up against the body). Obviously the lesson to be learned is contained in the design of any ANSI-compliant office chair: use 5 or more legs so the loss of one won't cause you to tip over.
The basic design is as safe or safer than winged designs like X-33. Also, you don't need a 3-mile runway, and you don't have to haul those useless wings into space and back every time. Multiple engines give you protection against engine failure, as landing weight of an operational SSTO would be between 5 and 10% of the takeoff weight. I.E. you only need to light 2 or 3 of your 10 engines to land safely.
The craft in question was called DC-X, and it achieved all of its goals in the hands of a small team with minimal funding ($70M for the whole program, flights, vehicle, and all) at McDonnell-Douglas Aerospace. It demonstrated vertical takeoff/landing on rocket thrust. It was able to perform the maneuver from re-entry attitude (nose first) to landing attitude (tail first) that a full scale craft would have to perform. It demonstrated fast turnaround (2 flights in 2 days). The problems happened *AFTER* it as handed over to NASA. They of course decided to rebuild it with a bigger fuel tank made out of an exotic aluminum-lithium alloy. When they were testing it, one of the landing legs failed to deploy, and it tipped over and burned. The follow-on (Delta Clipper) lost the competition to be the X-33 design.
What people are trying to point out is demonstrated in the small with DC-X. NASA loads up these type of programs with advanced technologies as soon as they get their hands on them. Consequently, they go over budget and past schedule and are cancelled (which is about to happen to the X-33 that Lockheed-Martin is building, except that they are afraid to do it before the election). What's needed is to take existing well developed technology and build some operational vehicles. If you canceled 2 shuttle flights (at an estimated $500M each), you could probably do just that. But NASA would never do it because it would endanger their entrenched bureaucracy.
OK, I feel better now having that out of my system....
Also interesting to see that Edwin Land and George Eastman were inducted in the same year (given the corporate wrestling matches that Polariod and Kodak have had over the years).
Actually, Apple is going the opposite way. The newer machines have a smaller boot rom and load a file containing all of the stuff that used to be in the rom. Maybe there's a convergence here... the traditional PC BIOS is too brain-dead, and the Mac had too much stuff (GUI code) in the ROM.
Slashdot Mirror
http://www.usda.gov/oce/reports/energy/net_energy_ balance.pdf
From the table on page 5 ... the energy output is 1.02 to 1.10 times the input if you only look at ethanol.
Here's another:
http://www.usda.gov/oce/reports/energy/aer-814.pdf
This one's conclusions have 1.34 as the ratio.
Corn is not the problem, converting corn sugar into ethanol. That's where 2/3 of the energy used goes.
I also note that it is common to see people who have to control spacecraft (especially those not in earth orbit) say that you cannot neglect the effects of solar radiation pressure on the spacecraft's attitude and trajectory. For example NASA's Microwave Anisotropy Probe plans to use solar radiation pressure for backup attitude control (see page 8) and at the very least, cannot neglect this force on the spacecraft.
I would tend to conclude that this guy doesn't really know what he's talking about.
But if they are talking about the software on the machine, why the emphasis on HP? Did HP fund the IA64 linux port? Perhaps they are referring to HP's willingness to sell a big pile of boxes with Linux as the operating system.
Do you seriously think that Microsoft is capable of producing a system that has tight enough security to prevent somebody from breaking their DRM scheme? If they released such a thing, within a week someone will discover that a buffer-overrun bug in drm.dll or some such thing lets you hack the DRM scheme to disable it or bypass it.
You can get the SAE document describing the interface for $80 or so (or you can do what I did and borrow it from a university library). Companies such as multiplex engineering and others sell interface blocks that convert the oddball OBD-II electrical interface on your car to RS-232 serial. Then you are free to write your own diagnostic software for your linux laptop. Most of the trouble codes are standardized but if you want more info get your car's service manual from HELM or some other source.
Of course I'd be remiss if I didn't point out that the automotive aftermarket industry (i.e. repair shops) fought to make sure that you could do these things. And it seems like some fraction of car dealers have always been run by crooks (or idiots).
If you can't find a copy of an older book to buy, check with your local library. You can usually do a multi-library search from a web site and then email a request for inter-library loan. For instance there are two copies of The Broken Sword in Minnesota libraries, one is the 1971 Ballentine (w/ intro by Lin Carter) and the other is the 1988 Baen edition.
For more info see:
PowerWall link
On the subject of triethyl borane, there is a very interesting book on the development of boron based fuels intended for the B-70 bomber: The green flame: surviving government secrecy by Andrew Dequasie. In order for the B-70 to have useful range at mach 3, more energy density was needed than hydrocarbon based fuels could provide, which led to research in various borane compounds. Unfortunately these compounds are extremely dangerous to work with (as the previous poster indicates) and the combustion products include boric oxide (boiling point 1860 C) which tends to solidify on the turbine blades of a turbojet. The project was cancelled along with the XB-70.
A correction and a comment... RS64-IV (aka IStar) has a 4 stage pipe, not 5. Also notable is that due to the short pipe, there is no branch penalty in most cases. This processor also has HMT (hardware multithreading). It only executes one thread at a time, but can switch threads on cache misses or other long latency events.
There are no big surprises here. NASA continues to try to build the most technically advanced craft possible, instead of actually building something that works. For a detailed description of how NASA screwed up and why X-33 is dead (written a year ago) see: http://www.space-access.org/updates/sau91.html
The real problem here is that NASA has become an enormous entrenched bureaucracy. They aren't interested in any solution that doesn't require an army of 10,000 engineers and technicians because then they won't be able to justify an legion of bureaucrats. The DC-X craft was built and tested on a shoestring over the objections of NASA. A scaled up SSTO based on that would require a support staff on the same order as a 747 (hundreds of people rather than tens of thousands as is the case for the shuttle) and would fly daily to weekly. For a detailed description of how we could have built such a craft as early as the '70s, see Halfway to Anywhere: achieving America's destiny in space by G. Harry Stine.
Another problem we have run into along the way here is that NASA has done everything it can to squash the independent, privately funded space transportation startups (Rotary Rocket, Beal, Kistler, etc.). NASA administrator Dan Goldin has made disparaging (and untrue) statements about their technologies which have contributed to their funding difficulties. In addition NASA continues to propose initiatives that would compete against these companies.
I still think NASA's planetary/space science programs (Pioneer/Voyager/Galileo/Cassini/etc.) are something to be proud of, but they have had to take a back seat to the "shuttle-station complex" (sing to the tune of "military-industrial complex") and that really disgusts me. What can you do about it?
Don't reply to this post! Instead, write, call, fax, or email your congresscritters (all 3 of them) and demand that we get NASA out of the launch vehicle development business.
If you think you can dump water on liquid sodium without a catastrophic hydrogen explosion, you've got another think coming. 2 Na + 2 H2O = 2 NaOH + H2 + a bunch of heat energy (which usually ignites the released H2 if O2 is present). This is why sodium metal is usually stored in some kind of oil (to prevent contact with water). A high-school chemistry prank I have heard of is to flush a chunk of sodium metal in a toilet. Sometimes, the toilet is even destroyed by the resulting hydrogen explosion in the sewer pipe.
I think strongARM based handhelds like the iPAQ probably exceed this machine's capabilities in every category except i/o (it had multiple SMD disk interfaces, SCSI, and a VME bus for slow stuff, if I recall correctly). I don't see why X wouldn't work quite nicely on the iPAQ if you had an appropriate toolkit that worked well with the 320x200 screen resolution.
iPAQ specs: http://www.compaq.com/ products/handhelds/pocketpc/H3650.html
There's no doubt that domestic pushrod engines can survive more abuse... a friend had a '79 Nova with the straight-6, it ran dry of oil at least twice and still ran reasonably well the last time I saw it at about 120000 miles.
As far as the mitsubishi 3.0 V6 goes, I have another friend with a plymouth acclaim that has one of these; yes, it leaks oil from every available orifice. Good thing it's a non-intereference engine because he's got over 160000 miles on it and hasn't changed the timing belt.
My personal preference (maybe it's an acquired taste) is to drive something smaller and lighter with an engine that likes to rev. I've had fun driving, maintaining (I do all my own work), and tuning my CRX for 12 years. I'm guessing from your email address that your preferences lie elsewhere....
I agree with what you're saying up to the point of saying that a civic will only last 120,000 miles. This may be true if the body totally rusts out. Thin sheet metal suffers badly from rust, as you say. But well maintained honda engines will last a lot longer than that. My '88 CRX Si has 196000 miles, uses no oil, gets 38mpg, and is still as fast as it was when it was new. (but yes, you do have to remove the left axle to replace the alternator )-: ). My '86 accord I bought a year ago with 220000 miles and now has 242000 miles. Similar story with that one; no oil consumption, 32mpg.
To get back to the topic, I'm waiting for the 2002 Civics, which are rumored to have an option for a hybrid gas/electric engine system similar to that used in the Insight.
DC-X tipped and burned because one of the landing legs did not deploy (stayed folded up against the body). Obviously the lesson to be learned is contained in the design of any ANSI-compliant office chair: use 5 or more legs so the loss of one won't cause you to tip over.
The basic design is as safe or safer than winged designs like X-33. Also, you don't need a 3-mile runway, and you don't have to haul those useless wings into space and back every time. Multiple engines give you protection against engine failure, as landing weight of an operational SSTO would be between 5 and 10% of the takeoff weight. I.E. you only need to light 2 or 3 of your 10 engines to land safely.
The craft in question was called DC-X, and it achieved all of its goals in the hands of a small team with minimal funding ($70M for the whole program, flights, vehicle, and all) at McDonnell-Douglas Aerospace. It demonstrated vertical takeoff/landing on rocket thrust. It was able to perform the maneuver from re-entry attitude (nose first) to landing attitude (tail first) that a full scale craft would have to perform. It demonstrated fast turnaround (2 flights in 2 days). The problems happened *AFTER* it as handed over to NASA. They of course decided to rebuild it with a bigger fuel tank made out of an exotic aluminum-lithium alloy. When they were testing it, one of the landing legs failed to deploy, and it tipped over and burned. The follow-on (Delta Clipper) lost the competition to be the X-33 design.
What people are trying to point out is demonstrated in the small with DC-X. NASA loads up these type of programs with advanced technologies as soon as they get their hands on them. Consequently, they go over budget and past schedule and are cancelled (which is about to happen to the X-33 that Lockheed-Martin is building, except that they are afraid to do it before the election). What's needed is to take existing well developed technology and build some operational vehicles. If you canceled 2 shuttle flights (at an estimated $500M each), you could probably do just that. But NASA would never do it because it would endanger their entrenched bureaucracy.
OK, I feel better now having that out of my system....
Also interesting to see that Edwin Land and George Eastman were inducted in the same year (given the corporate wrestling matches that Polariod and Kodak have had over the years).
I didn't see any mention of support for the Rage 128 chipset for 3.3.4 or 4.0 ... is there something I missed?
Actually, Apple is going the opposite way. The newer machines have a smaller boot rom and load
a file containing all of the stuff that used to be in the rom. Maybe there's a convergence here... the traditional PC BIOS is too brain-dead, and the Mac had too much stuff (GUI code) in the ROM.
Yes... and many years ago at a TUG conference a guy from MIT gave a presentation that described
a basic interpreter written in TeX.