Well, as with all wave dynamics, if you hit a wave with it's opposite, it cancels. Quite simple to think of why with sound. You have a high pressure peak and an equal low pressure peak that collide. The net effect is zero pressure (in relation to ambient atmospheric pressure).
OK, now that you explain it that way, it makes much more sense as I visualize it. I had always thought of it in terms of sine waves, where adding an opposite to a display merely doubles the amount of light coming from the screen, rather than in physical terms of what the molecules were doing.
I guess I need to spend less time looking at screens and more time standing in the wind.:)
I have a question about active cancellation, as I've heard of it being used in other places. Does the cancellation of a noise of a given frequency have any potentially harmful effects that become less obvious through cancellation? For example, does a high-pitch tone that could cause hearing loss over time become more dangerous now that there are two high-pitch tones (albeit directly off-phase) now sounding, or is the cancellation that complete?
Pick up some of the new fluid-drive-bearing units most companies are producing these days. I can hear my 60GB drives when they access, but the 250GB drive is completely without any detectable noise.
Of course, I do need one of the prof's nifty new toys for other parts of my system...
A large number of known asteroids are exactly that: clumps of rock weakly held together through their own weak gravitational forces.
This incidentally leads to one of the fears of trying to deflect such an asteroid were it on a collision with the earth -- that it would simply fragment it and cause destruction on a wider scale.
I never said to remove all of the regulations. What I said was that it should be opened up to competition, with streamlined rules that allow private contractors to do what is needed without someone trying to figure out if it will hurt NASA. Getting 100km up may be an order of magnitude easier than getting into LEO, but what happens if Rutan decides he wants to go into LEO? Then he's competing with NASA, and the only people that can get away with that are other nations because they don't have to comply with NASA's rules, and they don't want competition with their own aerospace agencies, either.
Incidentally, I find it somewhat confusing that you admit that privatization prevents abuses within agencies, but then suggest that it boosts abuses somewhere else. Companies are in it for the bottom line, and a lack of safety would compromise that. There's a reason that planes made 40 years ago are still able to fly (assuming proper maintenance) -- the companies, without any significant government funding -- decided that killing passengers would be a bad idea. Yes, problems still occasionally appear, but they're very rare -- much more rare than shuttle accidents have been.
Conservatives love killing off all parts of government not associated with the military or law enforcement.
Maybe because that's all it should be doing at the levels it does.
Look, I'm all for certain reasonable regulations and maybe a few social safety nets funded by FedGov, and NASA has done some very good things over the years that might have been at best difficult to do otherwise, but look at the budget sizes for the X-Prize stuff. Even the Rutan project isn't in the billions of dollars, though it would be if NASA had funded it. If there's anything where federal regulation needs to be eased, it's in the general area of spaceflight. Certification of craft means coming up with more explanations and filing more paperwork than just about anything short of an environmental review -- and that's when you're a government contractor. I know some of the X-Prize groups have gotten some red tape cut, but that was more to avoid the press hassles of the FAA appearing to slow things for no good reason. It took Sea Launch a few years and a few miracles to get their clearance, and even then their launches don't cross US soil at any relevant altitude.
NASA has become a feeding trough for contractors. Yes, they do some spectacular things, but at often vastly inflated costs. Let's see space opened fully for competition, and then see how fast costs can come down, even within NASA. Someone would be putting people into space quickly and inexpensively using simple booster/capsule technology, because it's simple, cheap, and it works incredibly well. We should be going back to this, not funding a new shuttle.
This goes back to the auditing. The government's accounting practices are often slip-shod at best. Invoices come into the mail room, often spend a couple of weeks getting routed around, and then end up in a pile, where it takes time to go through and pay them, assuming some clerk can find what it's attached to, at which point it gets held up until it can be matched with a known purchase, or is over-ridden by someone and paid -- usually, as you mentioned, well after the due date.
If it is, then there is ammo for killing a lot of government programs.
A few weeks ago, I made a post somewhere else about running independent audits on the government by an outside firm (or two). My guess was that in the course of a given year, something like $100 billion could be picked out as inefficiencies, waste, fraud, or abuse. Following a report last week about the Secret Service -- hardly the biggest agency -- unable to account for a few billion on its own, I wonder if my guess was far too low.
No... The F/A-18E/F is replacing the F-14. The F-35 is replacing the A-6, though it will almost certainly participate in air defense patrols as well, much like the original F/A-18 line did even while its primary use for the Navy was as a strike aircraft.
I'm almost certain that if they had the ability to tweak security in MS, they would do so.
They did, sort of, with the security guides, which are well-documented (if rather dry) explanations of how to use existing Windows functionality to improve security on the systems. Some of them are pretty clearly overkill for most people (minimum 12-character passwords and 4GB max size for each log file, for example), but they're generally pretty good use. Apparently, they had such an effect on Microsoft that MS wrote up a "Securing Windows Server 2003" document that was good enough that the NSA people decided that their own document wasn't needed. It's not a matter of laziness, either; they're still publishing and updating the other documents.
Still doesn't make Windows flawless, but it makes it a helluva lot better for those needing to lock things down.
Ferry range on the Super Hornet is about +200km over the Tomcat. The new Hornet can also carry another 4750 pounds of payload (assuming a runway takeoff; carrier takeoffs probably aren't too far apart).
The capabilities of the Super Hornet are where it pays off. While it's a much larger plane than the original Hornet (about 25% larger), it's just as fast, possibly more maneuverable, and simpler and less costly to maintain. The F-14 is a beast when it comes to maintenance; the variable-sweep wings require extra time, and the engines require a lot of time and energy.
The sole advantage in the Tomcat is in the Phoenix missile. With a range of 125+ miles, it can pick off many threats before they're even aware that the enemy is out there. However, the Navy had all kinds of problems with Hughes delivering bad guidance systems in the late 80s/mid 90s, and they cost almost $1M each, so even training was getting cut on them. The need for this kind of range has been negated, for the most part, by various methods of AWACS from the E-2C Hawkeye with upgrades to the full-blown AWACS aircraft that the USAF uses. They can identify targets and vector to within AMRAAM range (probably about 40 miles) for intercept.
The F-35's anti-armor capacity will be completely missile-based for now, though a laser system is in the works. There are concerns about the impact point becoming too bright for surrounding infantry -- it may be so bright for a moment from heating that blindness may ensue.
Actually, Ma Deuce is getting mostly replaced starting next year by the M-312.50-cal. It may stick around in cases where AA is needed (the M-312's cyclic rate is about half of the BMG's), but the new weapon is reportedly much lighter (43 pounds against 128 for the M2) and will be adaptable to fire 25mm high explosive smart rounds when development of that is complete. (The M-312 is a development of the M-307, which fires that 25mm round, and which needs only six parts changed to handle the.50 BMG round.
Unless the A35 works a WHOLE LOT like an A10 in real use, it is destined to go the way of the Comanche.
Unlikely. The F-35 is simply replacing too many aircraft:
* A-6 Intruder * A-10 (possibly) * F-16 * AV-8 Harrier * F/A-18 (some US strike missions, and several countries are switching to it completely) * Tornado (I think -- Britain's been trying to get rid of it for a while)
There's been some talk about this, using swarms of low-cost, high-altitude drones armed with Hellfires to rain death on armor. If your enemy fields 100 tanks, then you put 100 drones in place, and ripple fire them all from 60,000 feet. In seconds, the enemy has little to no armor, leaving its infantry without heavy support.
It's actually called a titanium bathtub. It was provided to help protect the pilot against larger guns than the 23mm cannon most prevalent in Soviet AAA and aircraft.
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Well, as with all wave dynamics, if you hit a wave with it's opposite, it cancels. Quite simple to think of why with sound. You have a high pressure peak and an equal low pressure peak that collide. The net effect is zero pressure (in relation to ambient atmospheric pressure).
:)
OK, now that you explain it that way, it makes much more sense as I visualize it. I had always thought of it in terms of sine waves, where adding an opposite to a display merely doubles the amount of light coming from the screen, rather than in physical terms of what the molecules were doing.
I guess I need to spend less time looking at screens and more time standing in the wind.
...
I have failed. Teh Stupid has arrived.
I have a question about active cancellation, as I've heard of it being used in other places. Does the cancellation of a noise of a given frequency have any potentially harmful effects that become less obvious through cancellation? For example, does a high-pitch tone that could cause hearing loss over time become more dangerous now that there are two high-pitch tones (albeit directly off-phase) now sounding, or is the cancellation that complete?
Pick up some of the new fluid-drive-bearing units most companies are producing these days. I can hear my 60GB drives when they access, but the 250GB drive is completely without any detectable noise.
Of course, I do need one of the prof's nifty new toys for other parts of my system...
Maybe on the inside. On the outside, they're already quiet enough that I miss when they're coming up behind me.
Damned cars always trying to stalk and eat me.
A large number of known asteroids are exactly that: clumps of rock weakly held together through their own weak gravitational forces.
This incidentally leads to one of the fears of trying to deflect such an asteroid were it on a collision with the earth -- that it would simply fragment it and cause destruction on a wider scale.
I never said to remove all of the regulations. What I said was that it should be opened up to competition, with streamlined rules that allow private contractors to do what is needed without someone trying to figure out if it will hurt NASA. Getting 100km up may be an order of magnitude easier than getting into LEO, but what happens if Rutan decides he wants to go into LEO? Then he's competing with NASA, and the only people that can get away with that are other nations because they don't have to comply with NASA's rules, and they don't want competition with their own aerospace agencies, either.
Incidentally, I find it somewhat confusing that you admit that privatization prevents abuses within agencies, but then suggest that it boosts abuses somewhere else. Companies are in it for the bottom line, and a lack of safety would compromise that. There's a reason that planes made 40 years ago are still able to fly (assuming proper maintenance) -- the companies, without any significant government funding -- decided that killing passengers would be a bad idea. Yes, problems still occasionally appear, but they're very rare -- much more rare than shuttle accidents have been.
Conservatives love killing off all parts of government not associated with the military or law enforcement.
Maybe because that's all it should be doing at the levels it does.
Look, I'm all for certain reasonable regulations and maybe a few social safety nets funded by FedGov, and NASA has done some very good things over the years that might have been at best difficult to do otherwise, but look at the budget sizes for the X-Prize stuff. Even the Rutan project isn't in the billions of dollars, though it would be if NASA had funded it. If there's anything where federal regulation needs to be eased, it's in the general area of spaceflight. Certification of craft means coming up with more explanations and filing more paperwork than just about anything short of an environmental review -- and that's when you're a government contractor. I know some of the X-Prize groups have gotten some red tape cut, but that was more to avoid the press hassles of the FAA appearing to slow things for no good reason. It took Sea Launch a few years and a few miracles to get their clearance, and even then their launches don't cross US soil at any relevant altitude.
NASA has become a feeding trough for contractors. Yes, they do some spectacular things, but at often vastly inflated costs. Let's see space opened fully for competition, and then see how fast costs can come down, even within NASA. Someone would be putting people into space quickly and inexpensively using simple booster/capsule technology, because it's simple, cheap, and it works incredibly well. We should be going back to this, not funding a new shuttle.
Weren't some manufacturers (possibly including Dell) including a base hard drive image in a hidden partition to avoid shipping CDs with systems?
This goes back to the auditing. The government's accounting practices are often slip-shod at best. Invoices come into the mail room, often spend a couple of weeks getting routed around, and then end up in a pile, where it takes time to go through and pay them, assuming some clerk can find what it's attached to, at which point it gets held up until it can be matched with a known purchase, or is over-ridden by someone and paid -- usually, as you mentioned, well after the due date.
If it is, then there is ammo for killing a lot of government programs.
A few weeks ago, I made a post somewhere else about running independent audits on the government by an outside firm (or two). My guess was that in the course of a given year, something like $100 billion could be picked out as inefficiencies, waste, fraud, or abuse. Following a report last week about the Secret Service -- hardly the biggest agency -- unable to account for a few billion on its own, I wonder if my guess was far too low.
No... The F/A-18E/F is replacing the F-14. The F-35 is replacing the A-6, though it will almost certainly participate in air defense patrols as well, much like the original F/A-18 line did even while its primary use for the Navy was as a strike aircraft.
Yeah, but a DVD changer doesn't get the geek chicks.
Him: Hey, I've got a 300-disc DVD changer!
Her: So you have a DVD jukebox?
Him: Well, yeah...
Her: That is SO 90's. I'm outta here.
Whereas for an array:
Him: Hey, I've got a terabyte array!
Her: Really? That's SO cool!
Him: Yeah! You can't imagine how much pr0n that is!
Her: I'm outta here.
Hmmm... I guess the array doesn't do much, either...
I'm almost certain that if they had the ability to tweak security in MS, they would do so.
They did, sort of, with the security guides, which are well-documented (if rather dry) explanations of how to use existing Windows functionality to improve security on the systems. Some of them are pretty clearly overkill for most people (minimum 12-character passwords and 4GB max size for each log file, for example), but they're generally pretty good use. Apparently, they had such an effect on Microsoft that MS wrote up a "Securing Windows Server 2003" document that was good enough that the NSA people decided that their own document wasn't needed. It's not a matter of laziness, either; they're still publishing and updating the other documents.
Still doesn't make Windows flawless, but it makes it a helluva lot better for those needing to lock things down.
Why else would it be so popular?
Ferry range on the Super Hornet is about +200km over the Tomcat. The new Hornet can also carry another 4750 pounds of payload (assuming a runway takeoff; carrier takeoffs probably aren't too far apart).
The capabilities of the Super Hornet are where it pays off. While it's a much larger plane than the original Hornet (about 25% larger), it's just as fast, possibly more maneuverable, and simpler and less costly to maintain. The F-14 is a beast when it comes to maintenance; the variable-sweep wings require extra time, and the engines require a lot of time and energy.
The sole advantage in the Tomcat is in the Phoenix missile. With a range of 125+ miles, it can pick off many threats before they're even aware that the enemy is out there. However, the Navy had all kinds of problems with Hughes delivering bad guidance systems in the late 80s/mid 90s, and they cost almost $1M each, so even training was getting cut on them. The need for this kind of range has been negated, for the most part, by various methods of AWACS from the E-2C Hawkeye with upgrades to the full-blown AWACS aircraft that the USAF uses. They can identify targets and vector to within AMRAAM range (probably about 40 miles) for intercept.
The F-35's anti-armor capacity will be completely missile-based for now, though a laser system is in the works. There are concerns about the impact point becoming too bright for surrounding infantry -- it may be so bright for a moment from heating that blindness may ensue.
The F-14 is scheduled to be phased out in 2007, replaced by Super Hornets.
Actually, Ma Deuce is getting mostly replaced starting next year by the M-312 .50-cal. It may stick around in cases where AA is needed (the M-312's cyclic rate is about half of the BMG's), but the new weapon is reportedly much lighter (43 pounds against 128 for the M2) and will be adaptable to fire 25mm high explosive smart rounds when development of that is complete. (The M-312 is a development of the M-307, which fires that 25mm round, and which needs only six parts changed to handle the .50 BMG round.
Unless the A35 works a WHOLE LOT like an A10 in real use, it is destined to go the way of the Comanche.
Unlikely. The F-35 is simply replacing too many aircraft:
* A-6 Intruder
* A-10 (possibly)
* F-16
* AV-8 Harrier
* F/A-18 (some US strike missions, and several countries are switching to it completely)
* Tornado (I think -- Britain's been trying to get rid of it for a while)
There's been some talk about this, using swarms of low-cost, high-altitude drones armed with Hellfires to rain death on armor. If your enemy fields 100 tanks, then you put 100 drones in place, and ripple fire them all from 60,000 feet. In seconds, the enemy has little to no armor, leaving its infantry without heavy support.
It's actually called a titanium bathtub. It was provided to help protect the pilot against larger guns than the 23mm cannon most prevalent in Soviet AAA and aircraft.
Spending $2 billion to shut down the Comanche program is a lot cheaper than $38 billion to continue it to completion.
No, the JSF program was just in the last stages of competition, narrowing it down from two designs (one Boeing, one Lockheed) to one (Lockheed's).