I'd be making a wild guess here, but I'd say the fuel would weigh much, much more. Look at how little mass is required on the Soyuz vehicle for an example.
Now imagine how much fuel would be required to decelerate the craft (a fairly hefty piece of mass) by even one Mach number. Now multiply that out to orbital velocity...
While you can't keep this going forever (energy is not free as in beer)
The great thing about this is that the sun's energy is absorbed by the elements used in this process (algae) to add some of the energy to the cycle that we are extracting energy from...
What better way to "get the word out" on your political party and its stance on various issues than to run for President?
It seems to me like it'd be a pretty cost-effective way to reach the people that aren't too into politics... the people that tend to vote every four years, at best.
Several hours?! Wow... that really, really sucks. I have no idea what could possibly take that long, given a default setup.
I wonder if it might be something resulting from the fact that the TiVo is already saving 2 MPEG2 streams in the background, while you are fiddling with the SP Manager? I never checked, does it keep buffering the tuners' data while it is recomputing the To Do list? I imagine that it does, as that'd be a pretty nasty feature gap. Maybe part of the problem is that the systems are woefully underpowered, memory bandwidth-wise, to handle all three operations... especially when the recomputation is large and complex (many SP's set to record all broadcasts)...
I'm interested in using something like this to be a universal remote that controls IR devices and devices accessible via VNC. I want a real universal remote... one that can control my AVR, DVD, TV as well as display a VNC session to my MP3 player PC.
BTW, anyone have any tips on doing this in a reasonably cost-effective manner?
It's probably making sure that every desired broadcast of each show can be recorded, in the case that there are overlaps. Two tuners, 30 shows, say maybe 20 channels, and about two weeks' worth of guide data. Add in the fact that it should look for re-broadcasts in the case of an overlap, and whether or not you want it to record reruns and keep as many shows as possible. It probably also keeps its own internal "To Do" list for things it has decided you "should" watch, so it has to go through and modify that as well.
I can see why it takes it a minute or two, but 5+ seems excessive. The longest mine has taken is about 2 minutes, when I did a major reordering of my 25-ish season passes, some of which were set to record every possible showing.
It still seems to me like that'd be a bad idea. The applications that use such a system would have to be written specifically to take advantage of it. If not, the driver/card would have to cache the entire frame's operations before being able to begin the real rendering pass.
Maybe it'd be better to just start at a 50/50 split, then based on which card finishes first, adjust the split per-frame to match the actual load of the scene? Or even use last frame's vertex-only results to compute the split factor for the next frame...
The problem with that is (I think) you've automatically made every frame at least two passes, one to figure out which card should render which portion of the screen, and one to actually do it. I need to read more about how they are getting the two cards to work together as well, though. It's most certainly not as simple as the Voodoo2 SLI systems:)
When you upgraded your mobo, did you upgrade your processor as well? IIRC, the A7N8X-E also supports dual channel memory access if you populate the appropriate DIMM slots. This could explain a large portion of your AGP 4x -> 8x upgrade.
For example, I have an Athlon 2000+ (1.67GHz, 266FSB). I have a 9800 Pro 128MB. Doom 3's timedemo performance was around 32fps, up to and including 1024x768. My friend with a slower card (9800 128MB non-Pro), but a faster CPU/mobo (nForce2-based with Athlon clocked at 333FSB and 13x multiplier, using the dual channel ram feature) gets timedemo performance around 45fps. I upgraded to a 6800 GT 256MB, and my performance went up to ~37fps (again, timedemo). I can get this performance all the way up to 1280x1024 4xAA, but it never goes higher.
The morale of this story is: there's more to modern games than GPU performance.
Are you sure you know what "T&L and other stuff" means? Transform & Lighting... nowadays, you need to think of it this way: Transform ~= Vertex Shader (vertex-level lighting is done here), Lighting ~= Pixel Shader. Given the advances in "T&L" with GPUs, do you really think that "that's a negligable part of the work nowadays"? So basically, because of the non-pixel-specific nature of Vertex Shading, each card needs to run the appropriate vertex program on each vertex that it might need to have data for in rasterization. They could do some neat stuff with sending particular fragments to another card for pixel shading, which may be what they are doing. That'd make this new SLI system likely to perform about as well as a single card with twice the memory bandwidth and twice the pixel shader pipelines. It'll certainly be faster, but IMHO, until it matures it won't get near 2x speed.
Do I detect a note of sarcasm? And how exactly is random noise the same as cyclic noise? If the cyclic noise turns out to be a pulsar, so be it. Either way, it would be an interesting discovery.
And if you are wondering, I have a degree in astronautical engineering. Does that mean that the above is right? Not at all! In fact, the bottle of wine I just helped finish says there is a good chance I am full of shit! No math was even attempted in this analysis....
Excellent. I don't have a degree in astronautics, but I did work for a competitor of AGI, building a "simplified" STK-style app (FreeFlyer, built by AI Solutions). I tried to keep my post simple for two reasons:
1) I wasn't sure how much I mis-remembered 2) I wanted to keep it non-technical enough for the AC that I was responding to, since s/he seemed to be missing some pretty important points of orbital mechanics
If geo is ~20K miles, why does the elevator need to be so long? Does this mean that they're now thinking about a lighter counter weight? They used to talk about capturing an asteroid.
Last I read, they are planning on using lighter counterweights: I mentioned it here
As far as I understand it (from the recent Discover article), once the ribbon is initially deployed (starts out small), they send up small lifters that build onto the main ribbon, increasing its width. These initial lifters would park at the end of the cable forever, increasing the size of the counterweight. They claim that the initial ribbon would take about 2 years to build to full width with this method. Additional ribbons could be constructed in 7 months each, for MUCH less cost... after all, they can use the first elevator to start the construction, instead of sending the initial materials up on big tanks of burning rocket fuel.
A couple of rebuttals, mainly from the recent issue of Discover magazine:
So your space station is makeing rather fast circles (ellipses to be exact) at 300km height and your elevator drops it of at 60000 miles. Stopping the elevator at 300km and letting the ISS pick up the cargo is impossible, unless the astronauts got a mighty set of reflexes as they pass the elevator at around 20000 km/h. If you let it go all the way to 60000 miles you need rockets to slow the cargo down and bring it in a lower orbit, it would probably be cheaper then launching it from earth, but would it be more efficient?
I think the idea for this is using the elevators to lift the mass up to an appropriate altitude and letting it go. Part of the mass is a booster rocket to get the mass into the appropriate orbit. It'd take a whole hell of a lot less rocket fuel to do this than to launch it directly from Earth's surface. Taking the mass to an altitude above geosynch and letting it go would give it a huge boost for getting out of Earth's gravity well. As far as efficiency, they are planning on driving these things with lasers powered by solar cells. I forget the exact details, but they imply that the propulsion systems are one of the easier components to develop for the project.
Next problem that might arise is the need to move the cable not only for satellites (a few hundred in operation) but also for the thousands of pieces of spacejunk larger then 1 cm. An encounter with such a piece would probablyy make the cable make a nasty "snap" sound, which noone could ever hear cause it's space.
IIRC, the main rebuttal for this is that the cable will be much wider than the minimum required for the target maximum liftable mass, and that there will be "repair lifters" that go up on occasion to patch holes in the ribbon cable. For the larger, trackable space junk masses, the cable will be tied down to a mobile oil rig platform to allow for evasive maneuvers.
Thirdly, 60000 miles? Geosynchronous orbit is at 42000km from the centre of earth, how the hell are they going to keep the "weight" where it's supposed to be? Rockets? Unless they manage to keep the centre of mass at 42000 km I don't think it's possible, and you'll end up with 60000 miles of expensive ribbon wrapped around earth (2.5 rounds) and a small crater where the "weight" met earth.
Above geosynch orbit altitude, masses "moving" (quoted because it depends on your reference frame) at the speed at which the weighted end would be moving tend to want to leave orbit. Put simply, things trying to maintain synchronous orbit (staying over one spot) below geosynch altitude want to fall (not moving fast enough), things at geosynch altitude stay where they are (speed is just right), and things above goesynch altitude want to leave orbit (moving too fast). For example, the moon's orbital speed is 1.03km/s (about 2200 mph, or about Mach 3), performing one revolution every ~28 days. The speed of something maintaining a geosynch orbit at 60k miles would be insanely fast, revolving once a day (at that altitude, it would be moving at ~7.5km/s). That would put a lot of stress (not sure how to calculate that) on the ribbon, which is part of the reason it needs to be so strong. The centripetal force would keep the cable taut. The weighted end would be quite massive, enough that the relatively small mass of the lifter and its cargo wouldn't cause enough of a change in mass to the elevator system as a whole.
Also, if the cable were to be in danger of getting dragged down, they'd probably just let it go, and the weighted end would rip the ribbon out into orbit and away. I don't think they are too worried about it getting dragged down, based on the designs I've read about.
The article in the recent Discover goes into more depth than the article attached to this thread... it even goes so far as to claim that many of the scientists that attend these conferences end up signing on to help the Space Elevator along towards being realized.
Wow, I didn't realize it had gotten that bad. I stopped playing when they moved authentication to Steam, so I guess I'm a little behind. Maybe something like that would work with HL2, once it gets hacked to hell... sigh. I was really looking forward to CS2, too.
I've always thought that some smart cheater-hater should come up with the ultimate cheat that just happens to be a trojan that transmits the cheaters' cd keys and/or steam ids back to a home server... then randomly add those IDs to a published "Master Ban Page" somewhere. It'd be great if said smart person could get Valve to secretly add code to the servers so that the ID transmission went through the game channel itself, then had the server send the data back through steam and then to the ban server for processing. You'd at least get a large list of kiddies that just want the latest and greatest hacks. Probably wouldn't do much good against cheat clans that have their own programmers and in-house hacks, though.
Slashdot Mirror
I'd be making a wild guess here, but I'd say the fuel would weigh much, much more. Look at how little mass is required on the Soyuz vehicle for an example.
Now imagine how much fuel would be required to decelerate the craft (a fairly hefty piece of mass) by even one Mach number. Now multiply that out to orbital velocity...
Would orbital reentry speeds be on the order of Mach 4?
Try Mach 20...
While you can't keep this going forever (energy is not free as in beer)
The great thing about this is that the sun's energy is absorbed by the elements used in this process (algae) to add some of the energy to the cycle that we are extracting energy from...
What better way to "get the word out" on your political party and its stance on various issues than to run for President?
It seems to me like it'd be a pretty cost-effective way to reach the people that aren't too into politics... the people that tend to vote every four years, at best.
Now imagine being one of the other 99,992 players that were unable to affect any portion of the storyline.
They can just hang some of that nifty new "Faraday cage" wallpaper... the stuff that blocks RF.
And here I thought Alpha had been dead for years... maybe it was just the impression DEC gave. Perhaps this is a lesson in self-fulfilling prophecy.
Nevermind, I found a source for range data...
Thanks for the info, I'll look into it.
:)
How is the IR tranmitter on the Tungsten C? Can I get 5m range? More? I want to drive my A/V components too
Several hours?! Wow... that really, really sucks. I have no idea what could possibly take that long, given a default setup.
I wonder if it might be something resulting from the fact that the TiVo is already saving 2 MPEG2 streams in the background, while you are fiddling with the SP Manager? I never checked, does it keep buffering the tuners' data while it is recomputing the To Do list? I imagine that it does, as that'd be a pretty nasty feature gap. Maybe part of the problem is that the systems are woefully underpowered, memory bandwidth-wise, to handle all three operations... especially when the recomputation is large and complex (many SP's set to record all broadcasts)...
I'm interested in using something like this to be a universal remote that controls IR devices and devices accessible via VNC. I want a real universal remote... one that can control my AVR, DVD, TV as well as display a VNC session to my MP3 player PC.
BTW, anyone have any tips on doing this in a reasonably cost-effective manner?
It's probably making sure that every desired broadcast of each show can be recorded, in the case that there are overlaps. Two tuners, 30 shows, say maybe 20 channels, and about two weeks' worth of guide data. Add in the fact that it should look for re-broadcasts in the case of an overlap, and whether or not you want it to record reruns and keep as many shows as possible. It probably also keeps its own internal "To Do" list for things it has decided you "should" watch, so it has to go through and modify that as well.
I can see why it takes it a minute or two, but 5+ seems excessive. The longest mine has taken is about 2 minutes, when I did a major reordering of my 25-ish season passes, some of which were set to record every possible showing.
Much cheaper, but not nearly as fast...
It still seems to me like that'd be a bad idea. The applications that use such a system would have to be written specifically to take advantage of it. If not, the driver/card would have to cache the entire frame's operations before being able to begin the real rendering pass.
Maybe it'd be better to just start at a 50/50 split, then based on which card finishes first, adjust the split per-frame to match the actual load of the scene? Or even use last frame's vertex-only results to compute the split factor for the next frame...
The problem with that is (I think) you've automatically made every frame at least two passes, one to figure out which card should render which portion of the screen, and one to actually do it. I need to read more about how they are getting the two cards to work together as well, though. It's most certainly not as simple as the Voodoo2 SLI systems :)
When you upgraded your mobo, did you upgrade your processor as well? IIRC, the A7N8X-E also supports dual channel memory access if you populate the appropriate DIMM slots. This could explain a large portion of your AGP 4x -> 8x upgrade.
For example, I have an Athlon 2000+ (1.67GHz, 266FSB). I have a 9800 Pro 128MB. Doom 3's timedemo performance was around 32fps, up to and including 1024x768. My friend with a slower card (9800 128MB non-Pro), but a faster CPU/mobo (nForce2-based with Athlon clocked at 333FSB and 13x multiplier, using the dual channel ram feature) gets timedemo performance around 45fps. I upgraded to a 6800 GT 256MB, and my performance went up to ~37fps (again, timedemo). I can get this performance all the way up to 1280x1024 4xAA, but it never goes higher.
The morale of this story is: there's more to modern games than GPU performance.
Are you sure you know what "T&L and other stuff" means? Transform & Lighting... nowadays, you need to think of it this way: Transform ~= Vertex Shader (vertex-level lighting is done here), Lighting ~= Pixel Shader. Given the advances in "T&L" with GPUs, do you really think that "that's a negligable part of the work nowadays"? So basically, because of the non-pixel-specific nature of Vertex Shading, each card needs to run the appropriate vertex program on each vertex that it might need to have data for in rasterization. They could do some neat stuff with sending particular fragments to another card for pixel shading, which may be what they are doing. That'd make this new SLI system likely to perform about as well as a single card with twice the memory bandwidth and twice the pixel shader pipelines. It'll certainly be faster, but IMHO, until it matures it won't get near 2x speed.
Do I detect a note of sarcasm? And how exactly is random noise the same as cyclic noise? If the cyclic noise turns out to be a pulsar, so be it. Either way, it would be an interesting discovery.
Random noise from machinery would likely appear the same as random noise from a star, but such things tend to generate noise that is cyclic.
Excellent. I don't have a degree in astronautics, but I did work for a competitor of AGI, building a "simplified" STK-style app (FreeFlyer, built by AI Solutions). I tried to keep my post simple for two reasons:
1) I wasn't sure how much I mis-remembered
2) I wanted to keep it non-technical enough for the AC that I was responding to, since s/he seemed to be missing some pretty important points of orbital mechanics
Last I read, they are planning on using lighter counterweights: I mentioned it here
As far as I understand it (from the recent Discover article), once the ribbon is initially deployed (starts out small), they send up small lifters that build onto the main ribbon, increasing its width. These initial lifters would park at the end of the cable forever, increasing the size of the counterweight. They claim that the initial ribbon would take about 2 years to build to full width with this method. Additional ribbons could be constructed in 7 months each, for MUCH less cost... after all, they can use the first elevator to start the construction, instead of sending the initial materials up on big tanks of burning rocket fuel.
I think the idea for this is using the elevators to lift the mass up to an appropriate altitude and letting it go. Part of the mass is a booster rocket to get the mass into the appropriate orbit. It'd take a whole hell of a lot less rocket fuel to do this than to launch it directly from Earth's surface. Taking the mass to an altitude above geosynch and letting it go would give it a huge boost for getting out of Earth's gravity well. As far as efficiency, they are planning on driving these things with lasers powered by solar cells. I forget the exact details, but they imply that the propulsion systems are one of the easier components to develop for the project.
IIRC, the main rebuttal for this is that the cable will be much wider than the minimum required for the target maximum liftable mass, and that there will be "repair lifters" that go up on occasion to patch holes in the ribbon cable. For the larger, trackable space junk masses, the cable will be tied down to a mobile oil rig platform to allow for evasive maneuvers.
Above geosynch orbit altitude, masses "moving" (quoted because it depends on your reference frame) at the speed at which the weighted end would be moving tend to want to leave orbit. Put simply, things trying to maintain synchronous orbit (staying over one spot) below geosynch altitude want to fall (not moving fast enough), things at geosynch altitude stay where they are (speed is just right), and things above goesynch altitude want to leave orbit (moving too fast). For example, the moon's orbital speed is 1.03km/s (about 2200 mph, or about Mach 3), performing one revolution every ~28 days. The speed of something maintaining a geosynch orbit at 60k miles would be insanely fast, revolving once a day (at that altitude, it would be moving at ~7.5km/s). That would put a lot of stress (not sure how to calculate that) on the ribbon, which is part of the reason it needs to be so strong. The centripetal force would keep the cable taut. The weighted end would be quite massive, enough that the relatively small mass of the lifter and its cargo wouldn't cause enough of a change in mass to the elevator system as a whole.
Also, if the cable were to be in danger of getting dragged down, they'd probably just let it go, and the weighted end would rip the ribbon out into orbit and away. I don't think they are too worried about it getting dragged down, based on the designs I've read about.
The article in the recent Discover goes into more depth than the article attached to this thread... it even goes so far as to claim that many of the scientists that attend these conferences end up signing on to help the Space Elevator along towards being realized.
Wow, I didn't realize it had gotten that bad. I stopped playing when they moved authentication to Steam, so I guess I'm a little behind. Maybe something like that would work with HL2, once it gets hacked to hell... sigh. I was really looking forward to CS2, too.
I've always thought that some smart cheater-hater should come up with the ultimate cheat that just happens to be a trojan that transmits the cheaters' cd keys and/or steam ids back to a home server... then randomly add those IDs to a published "Master Ban Page" somewhere. It'd be great if said smart person could get Valve to secretly add code to the servers so that the ID transmission went through the game channel itself, then had the server send the data back through steam and then to the ban server for processing. You'd at least get a large list of kiddies that just want the latest and greatest hacks. Probably wouldn't do much good against cheat clans that have their own programmers and in-house hacks, though.