Couple of problems with this.. First, the internal surfaces of a divergent (subsonic) duct experience adverse pressure gradients. This means you need to very gradually increase the duct area in order to prevent flow separation. Subsequently, you would need an extremely long duct to achieve an appreciable reduction in flow velocity, all of which is subject to friction and viscous drag. All in all, not good.
The second major problem with this is that a divergent duct in supersonic flow actually increases the flow velocity. You may notice in engines that possess a throat (i.e. the exhaust stream is supersonic), the duct area increases, accelerating the flow (take rocket engines for example). In order to slow down supersonic flow, you need a converging duct.
Aside from that, a couple other points.. shockwaves don't make flow turbulent. In fact, nearly all flow through a jet engine is turbulent, as opposed to laminar. This is actually desirable in most cases, because although turbulent flow causes an increase in skin friction drag, it is highly beneficial in delaying flow separation, which is very bad in most cases.
Finally, with respect to the ramjet, there are some serious issues still to overcome, especially for slower speeds. First and foremost, it can generate no static thrust, meaning you need an alternative means for propulsion to get your bird off the ground. This adds weight and takes up volume, both of which are very bad things.
And as for how fast it goes.. The faster a ramjet travels, the higher the increase in stagnation temperature of the flow. This affects how combustion occurs, and it actually reaches a point that by adding fuel and combustion it, you are cooling off the flow, which is the opposite effect that you desire. This upper limit on speed depends a great deal on the inlet design and the materials used, but in general it is sub-hypersonic (as in hypersonic speeds are too high).
Work is being done to develop a scramjet (supersonic combusition ramjet), which is essentially the same as a ramjet except that the combustion occurs while the flow is travelling at supersonic velocities (meaning less of an increase in stagnation temperature, less pressure loss, etc.), as well as schramjets, which again are similar, however use detonation waves to ignite the fuel/air, reducing profile drag due to burners and flameholders etc.
I hope this at least answered parts of your questions..
You're right, it isn't very hard to understand. Fortunately for them, there's more to it than just understanding that simple fact. Say you want to bring in a system like this.. what are the optimum values for server load to balance speed and energy efficiency? What are the costs involved with bringing hardware on and offline all the time?
They are performing research to gain further insight and data accumulation, something that takes much more than just "oh sure, I know power consumption != load."
Bingo! As your kids are growing up, do not give them a computer with net access in their own room. Keep an eye on them; they are in uncharted territory and are learning as they go. Help them learn some of the dangers and pitfalls of the internet.
As they grow up, you can gradually give them more privacy with computer and internet issues (as you should be giving them in other things as well), easing them into "adulthood." I don't understand how people expect an individual that has been sheltered her entire life to magically and suddenly be ready to take on the internet at midnight on her 18th birthday.
You have to gradually ease them into it, so that by the time they turn 18, they are ready for the internet. Because you helped to prepare them, their 18th birthday will simply be an official sign-post, but they won't notice any difference at all, since you've already reached the point where you trust your children to be responsible.
I believe it is intentional, because immediately outside the lecture halls (still inside the building) reception is perfectly fine, but as soon as you pass through the doorway it drops off to nil.
Notice I said "lecture hall", not "exam room".. also, there are phones and PAs hardwired in the room, so if a code were issued instructors would be informed via this means, just like any other school. It's pretty naive of you to think that students' cell-phones are the only way for security information to make its way around a school.
You don't need this paint to silence cell-phones in a theatre.. conventional construction techniques already exist to block wireless communication.
Here at the University of Toronto, there are several large lecture halls in the Bahen Institute of Technology building that are shielded, preventing students from using cell-phones, PDAs, wireless internet, etc.
I suspect in the case of movie theatres they have done some studies and decided that for whatever reason it is a better idea not to shield the movie halls. Whether this has to with liability issues or what, I don't know..
I think what the movie makers intended was to draw in the largest audience possible. Not everyone likes comic books, but how many people in the North American movie market do you think have never heard that song before?
Yes, I also found the typing notification change quite annoying; I much prefer a little icon in the corner of the window or something, or in a status bar, but for the love of god not right in the middle of what I'm trying to read!
It's also annoying if the person you're talking to decides not to send their message after all, because then you're left with a blank space instead of the previous message being located at the bottom of the chat window.
If the "Print this page" version is just the same page using a stylesheet specifically for print media, then in Firefox you can go to View->Page Style and select the one for print.
Did they ever make any money from their attempts at suing people? I'm afraid I didn't really keep up to speed.. I heard they were doing it and lost what little interest I had in following their career.
If so, I think it would go a long way to make a formal apology to those people they won money from and return the damages.
According to Ben Rich's book "Skunk Works", it wasn't that they optimized it for flight as opposed to on the ground.. it was that no one could come up with a tank sealant that could withstand the intense heats required for Mach 3 flight.
From the book (page 206):
[Kelly Johnson] offered five hundred bucks to anyone who could come up with an effective high-temperature fuel-tank sealant. No one collected that dough either, and our airplane would sit on the tarmac leaking fuel from every pore. But fortunately the tanks sealed themselves in flight from the heat generated by supersonic speeds.
I find this announcement re: the Nighthawk (and this discussion re: the SR-71) quite fascinating, as I am about 2/3 of the way through "Skunk Works" =P
Aikon-
p.s. Kelly Johnson ran the Skunk Works back in the U-2 and A-12 days, then retired and Ben Rich (the author above) took over. It was under Rich that they developed the F-117.
Because, you know, it's not like you already have an electrical infrastructure. The nice thing about electricity as a means of transporting energy is that it doesn't care where it came from.
You could have coal plants, nuclear plants, solar plants, hydro plants, or fusion plants, and all their output goes into the same grid that already exists. Electricity from solar energy doesn't need a special set of tubes to deliver it to your home.
In general, carbon fiber is strong in both compression and tension. Very strong. Where carbon fiber lacks stiffness is in bending and torsion.
However, this is quite easy to overcome. To overcome bending, just use carbon fiber strips with the fiber aligned along the length of a beam. Place them on the top and bottom of the beam; since under a downward load, the top of a beam will experience tension while they bottom will experience compression. You could possibly add a carbon shear web, aligned vertically compared to the top and bottom of the beam, with fibers running at 45 degrees down and up.
To overcome torsion, do something similar, but make it box. Wrap the entire box in carbon fiber with the fibers running at 45 degrees (both 45s).
All this adds weight, however, so you only add stiffness in a particular type of loading if you actually require your structure to be able to take it.
The Canadian robot manipulators! We've got tons of them! The arms on the space shuttles, the twin-armed contraption on the space station, numerous smaller manipulators on many rovers...
It's too bad any new ones won't be Canadian anymore with MDA selling out =( Not that MDA Space Missions / MD Robotics / Dynacs / SPAR were "all Canadian" to start with, but at least it had that "built here!" feeling to it.
I assumed the OP was using hyperbole to make his point; most cases of P2P throttling I have heard of are around 30KiB/s or 50KiB/s. I have never heard of a case of P2P throttling where the speeds were crippled so completely and utterly as to reach dialup speeds.
Erm, no. During "non-peak" hours (whatever those are.. I have never been told when "peak" is), my upload is well above 50KiB/s (I cap it to 50 out of personal preference, but this is beside the point anyway); my downloads normally run about 500KiB/s. Come "peak hours" (this time does not seem to be consistent from night to night), these download speeds drop suddenly to 30KiB/s on the dot and sit there for the rest of the night.
I have performed this test with both public and private trackers; and by private trackers I don't just mean "invite-only" trackers, I also mean someone with a private server that set up a tracker specifically for me to test this out. Just because you aren't getting capped doesn't mean other people aren't. I suggest you be grateful for what you have =/
An excellent point that I didn't even think of until you mentioned it. I totally agree; I'm on Bell where I am and it's awful; ALL of my P2P traffic is capped to 30KiB/s and it's quite painful when I should be able to access that content in a matter of minutes as opposed to a matter of hours.
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Couple of problems with this.. First, the internal surfaces of a divergent (subsonic) duct experience adverse pressure gradients. This means you need to very gradually increase the duct area in order to prevent flow separation. Subsequently, you would need an extremely long duct to achieve an appreciable reduction in flow velocity, all of which is subject to friction and viscous drag. All in all, not good.
The second major problem with this is that a divergent duct in supersonic flow actually increases the flow velocity. You may notice in engines that possess a throat (i.e. the exhaust stream is supersonic), the duct area increases, accelerating the flow (take rocket engines for example). In order to slow down supersonic flow, you need a converging duct.
Aside from that, a couple other points.. shockwaves don't make flow turbulent. In fact, nearly all flow through a jet engine is turbulent, as opposed to laminar. This is actually desirable in most cases, because although turbulent flow causes an increase in skin friction drag, it is highly beneficial in delaying flow separation, which is very bad in most cases.
Finally, with respect to the ramjet, there are some serious issues still to overcome, especially for slower speeds. First and foremost, it can generate no static thrust, meaning you need an alternative means for propulsion to get your bird off the ground. This adds weight and takes up volume, both of which are very bad things.
And as for how fast it goes.. The faster a ramjet travels, the higher the increase in stagnation temperature of the flow. This affects how combustion occurs, and it actually reaches a point that by adding fuel and combustion it, you are cooling off the flow, which is the opposite effect that you desire. This upper limit on speed depends a great deal on the inlet design and the materials used, but in general it is sub-hypersonic (as in hypersonic speeds are too high).
Work is being done to develop a scramjet (supersonic combusition ramjet), which is essentially the same as a ramjet except that the combustion occurs while the flow is travelling at supersonic velocities (meaning less of an increase in stagnation temperature, less pressure loss, etc.), as well as schramjets, which again are similar, however use detonation waves to ignite the fuel/air, reducing profile drag due to burners and flameholders etc.
I hope this at least answered parts of your questions..
Aikon-
You're right, it isn't very hard to understand. Fortunately for them, there's more to it than just understanding that simple fact. Say you want to bring in a system like this.. what are the optimum values for server load to balance speed and energy efficiency? What are the costs involved with bringing hardware on and offline all the time?
They are performing research to gain further insight and data accumulation, something that takes much more than just "oh sure, I know power consumption != load."
Aikon-
Bingo! As your kids are growing up, do not give them a computer with net access in their own room. Keep an eye on them; they are in uncharted territory and are learning as they go. Help them learn some of the dangers and pitfalls of the internet.
As they grow up, you can gradually give them more privacy with computer and internet issues (as you should be giving them in other things as well), easing them into "adulthood." I don't understand how people expect an individual that has been sheltered her entire life to magically and suddenly be ready to take on the internet at midnight on her 18th birthday.
You have to gradually ease them into it, so that by the time they turn 18, they are ready for the internet. Because you helped to prepare them, their 18th birthday will simply be an official sign-post, but they won't notice any difference at all, since you've already reached the point where you trust your children to be responsible.
Aikon-
Well, it is a gaming keyboard.. I kind of took the Windows user thing as given.
Aikon-
I believe it is intentional, because immediately outside the lecture halls (still inside the building) reception is perfectly fine, but as soon as you pass through the doorway it drops off to nil.
Notice I said "lecture hall", not "exam room".. also, there are phones and PAs hardwired in the room, so if a code were issued instructors would be informed via this means, just like any other school. It's pretty naive of you to think that students' cell-phones are the only way for security information to make its way around a school.
You don't need this paint to silence cell-phones in a theatre.. conventional construction techniques already exist to block wireless communication.
Here at the University of Toronto, there are several large lecture halls in the Bahen Institute of Technology building that are shielded, preventing students from using cell-phones, PDAs, wireless internet, etc.
I suspect in the case of movie theatres they have done some studies and decided that for whatever reason it is a better idea not to shield the movie halls. Whether this has to with liability issues or what, I don't know..
Aikon-
I think what the movie makers intended was to draw in the largest audience possible. Not everyone likes comic books, but how many people in the North American movie market do you think have never heard that song before?
Aikon-
Yes, I also found the typing notification change quite annoying; I much prefer a little icon in the corner of the window or something, or in a status bar, but for the love of god not right in the middle of what I'm trying to read!
It's also annoying if the person you're talking to decides not to send their message after all, because then you're left with a blank space instead of the previous message being located at the bottom of the chat window.
Aikon-
So, if I understand you correctly, what you're saying is that... This could be the Year of the Linux Desktop?
Aikon-
If the "Print this page" version is just the same page using a stylesheet specifically for print media, then in Firefox you can go to View->Page Style and select the one for print.
Aikon-
This is one of the problems with GIMP.. Who wants to show someone a picture that they edited and say "I GIMPed her in this picture"?
Aikon-
Did they ever make any money from their attempts at suing people? I'm afraid I didn't really keep up to speed.. I heard they were doing it and lost what little interest I had in following their career.
If so, I think it would go a long way to make a formal apology to those people they won money from and return the damages.
Aikon-
Exactly. Metallica has already shown to the music-going world what they think of their customers and fans, and many aren't likely to forget that.
Trent Reznor's efforts are incredibly successful because he shows the utmost respect for his fans.
Aikon-
You expect us to care about someone who is themselves admittedly intolerant of others?
Aikon-
*Whooooosh*
Aikon-
According to Ben Rich's book "Skunk Works", it wasn't that they optimized it for flight as opposed to on the ground.. it was that no one could come up with a tank sealant that could withstand the intense heats required for Mach 3 flight.
From the book (page 206):
I find this announcement re: the Nighthawk (and this discussion re: the SR-71) quite fascinating, as I am about 2/3 of the way through "Skunk Works" =P
Aikon-
p.s. Kelly Johnson ran the Skunk Works back in the U-2 and A-12 days, then retired and Ben Rich (the author above) took over. It was under Rich that they developed the F-117.
IIRC, the Archangel-12 was a smaller and lighter single-seater version? But yes, same basic body structure and construction methods.
Because, you know, it's not like you already have an electrical infrastructure. The nice thing about electricity as a means of transporting energy is that it doesn't care where it came from.
You could have coal plants, nuclear plants, solar plants, hydro plants, or fusion plants, and all their output goes into the same grid that already exists. Electricity from solar energy doesn't need a special set of tubes to deliver it to your home.
Aikon-
Somehow I don't expect this difference engine to start baking people cakes.
Aikon-
In general, carbon fiber is strong in both compression and tension. Very strong. Where carbon fiber lacks stiffness is in bending and torsion.
However, this is quite easy to overcome. To overcome bending, just use carbon fiber strips with the fiber aligned along the length of a beam. Place them on the top and bottom of the beam; since under a downward load, the top of a beam will experience tension while they bottom will experience compression. You could possibly add a carbon shear web, aligned vertically compared to the top and bottom of the beam, with fibers running at 45 degrees down and up.
To overcome torsion, do something similar, but make it box. Wrap the entire box in carbon fiber with the fibers running at 45 degrees (both 45s).
All this adds weight, however, so you only add stiffness in a particular type of loading if you actually require your structure to be able to take it.
Aikon-
The Canadian robot manipulators! We've got tons of them! The arms on the space shuttles, the twin-armed contraption on the space station, numerous smaller manipulators on many rovers...
It's too bad any new ones won't be Canadian anymore with MDA selling out =( Not that MDA Space Missions / MD Robotics / Dynacs / SPAR were "all Canadian" to start with, but at least it had that "built here!" feeling to it.
Aikon-
I assumed the OP was using hyperbole to make his point; most cases of P2P throttling I have heard of are around 30KiB/s or 50KiB/s. I have never heard of a case of P2P throttling where the speeds were crippled so completely and utterly as to reach dialup speeds.
Aikon-
Erm, no. During "non-peak" hours (whatever those are.. I have never been told when "peak" is), my upload is well above 50KiB/s (I cap it to 50 out of personal preference, but this is beside the point anyway); my downloads normally run about 500KiB/s. Come "peak hours" (this time does not seem to be consistent from night to night), these download speeds drop suddenly to 30KiB/s on the dot and sit there for the rest of the night.
I have performed this test with both public and private trackers; and by private trackers I don't just mean "invite-only" trackers, I also mean someone with a private server that set up a tracker specifically for me to test this out. Just because you aren't getting capped doesn't mean other people aren't. I suggest you be grateful for what you have =/
Aikon-
An excellent point that I didn't even think of until you mentioned it. I totally agree; I'm on Bell where I am and it's awful; ALL of my P2P traffic is capped to 30KiB/s and it's quite painful when I should be able to access that content in a matter of minutes as opposed to a matter of hours.
Aikon-