Due to spacecraft (or aircraft) motion, stereo pairs are generated along the flightpath if sequential images overlap. In many systems, each image n generates overlap with both image n+1 and n+2. Given the ability to launch two cameras, why not launch a single camera with more capabilities?
Another minor, and common, error is that the Cartosat-1 has a 2.5m pixel on its CCD, which does not transalate into a 2.5m "resolution." CCD resolution corresponds to Ground Sampled Distance (GSD), or the amount of ground sampled on one pixel. Ground resolved distance, (GRD), measures the highest frequency visible in the image and is what we normally think of as "resolution." As a result, for electro optical systems, GRD = 2 x GSD.
What the Clickable Culture story missed is that today's Wall Street Journal reported that the Second Life resident has sold the real world publishing rights of Tringo to Sean Ryan's Donnerwood Media for "low five figures." They plan to publish Tringo for mobile phones and on the web. Also mentioned over at Terra Nova.
"A spacecraft equipped with a telescope would trail tens of thousands of miles behind the starshade to collect and process the light."
How about reading the article (all 297 words) before posting?
1) The research will only go forward with more funding
2) SRI International is involved ("No, really, Uri Geller *is* a psychic!")
3) "Mike McKubre from SRI International, in Menlo Park, Calif., a respected researcher who is influential among those pursuing cold fusion" is not the same as "Mike McKubre, a respected researched who is also working on cold fusion"
4) It's an election year and DOE, hardly a bastion of good science under Bush, is about to announce Cold Fusion is workable at a time of record world oil prices?
Second Life already has a vibrant economy driven by user-created content and some users are choosing to convert their in-world earnings back in US$ via Gaming Open Market. Terra Nova has extensive discussions of the strength of the SL economy, as well as some of the problems that can arise from using real-world currency in virtual worlds -- including resident alienation, loss of suspension of disbelief, and interesting legal implications. It is also somewhat specious to suggest that pulling real-world currency into a virtual world somehow enables user-created content. The billing system, whether in US$ or SL's L$, was certainly a complicated component of the overall product, but it was dwarfed by the complexities of 3D streaming, collaborative creation, and distributed physical simulation.
In a similar way, some Second Life users decided that they wanted to be able to play a traditional RPG within Second Life. The result of their creation was Dark Life, captured in SL's New World Notes. The Dark Lifers have been quite successful and have drawn many players into their game, including many new users. In addition to the usual creature killing, magic spells, healing and leveling, they have also introduced some very interesting twists on traditional RPG gameplay.
This discussion occurred in the afternoon/evening after State of Play. It was very interesting to learn about the rulemaking process. For those who aren't familiar with it, rulemaking is when government agencies convert policy decisions passed by congress ("reduce automobile emissions") into actual federal statutes ("all light trucks lines will reduce their average emissions by 5% by 2007"). Part of the rulemaking process is posting the proposed rules and then soliciting public comment. In the old system, these periods of feedback were announced via the Federal Register and feedback was submitted via snail mail. The result was that a small number of lobbyists and individuals who scoured the Register would submit feedback. The agency in charge of the new statute would then publish a response, and eventually, the new law. The government doesn't have to follow the feedback but is often influenced by multiple submissions with similar viewpoints.
The new system (partially implemented) allows for automated searching of proposed rules and electronic responses. A requirement is that posting be anonymous.
As readers of/. can see, this is a very gamable system. The lobbyists now have a cheap and easy way to scan all proposed rules for ones that touch on their area and a undetectable way to submit massive numbers of similar viewpoints from apparently multiple sources. The new system is supposed to make the system more democratic but the actual result is to make it less democratic. Somehow not at all shocking that the Wired article missed that.
Now, given that there were many smart game designers/developers in the room who've had experiences managing communities that are full of people who try to game systems, there were ideas put forth --/. was even mentioned -- but the government folks who were there weren't particularly interested in hearing that there system was flawed. Instead they just wanted information on how to educate people about the new system.
It was an enlightening and terrifying view into how senior government employees attack problems.
Second Life has been hapily using NSIS -- featuring Super-PIMP(tm) technology -- for 3 years. We played with just about all of the different installers and settled on NSIS because it generated by far the fastest installs and also created the smallest files. Throw in the fact that it was incredibly easy to use and you had a winner. We haven't switched over to 2.0, though.
I can't speak to the standard, but I can cover our experiences using Jpeg2000. In early 2001, the Second Life team did an evaluation of available still image compression schemes in order to determine whether an off-the-shelf solution would meet our requirements of providing flawless visual reproduction at 10:1 compression while preserving chroma at compressions of 100:1 or more, allowing progressive streaming in order to handle level of detail and mipmapping, and be high performance enough to allow for multiple packet decodes per game frame. We went into the search assuming that we would end up having to write out own compression scheme and were pleasantly surprised by the performance of Jpeg2000. We selected the Kakadu libraries for Jpeg2000 compression and decompression and have been happily using them for 3 years on Linux, Mac, and Windows.
It is a shame that Jpeg2000 hasn't seen wider adoption, as it is visually far superior to Jpeg at similar compression levels, especially in reduced "ringing" around high-frequency edges, and its ability to handle progressive streaming is incredibly useful in interactive environments. In Second Life's case, images as large as 2048x2048 are delivered interactively to the client viewer, with a single packet providing enough detail for distant textures. As the user approaches textures, additional packets are delivered to the client, providing a progressive increase in detail with very low latency, thanks to Jpeg2000's ability to deliver fine-grained increases. Kakadu's high performance has also been critical, since many scenes in Second Life have thousands of different textures in view because of user created and uploaded textures.
The "hacking your metabolism" argument is not well defended by the research. However, the constraints of not eating carbos does tend to reduce your caloric intake, leading to weight loss.
For a college engineering course we had to do some massive analysis of an analog feedback control system. For the assignment we were supposed to use MATLAB running on our VAX 11/780 cluster. I had the (then very new and uber-cool) HP 28S clamshell so I programmed the various matrix operations into it and then went to the computer lab late at night race the cluster. I don't remember the exact numbers but the HP finished in many seconds while MATLAB spun for many minutes which I remembered thinking was pretty amazing.
For what it's worth, at WWDC the Blizzard guys said that Warcraft 3 was running around twice as fast on the dual 2GHz G5 as on a dual 1.4GHz G4, and that it ran out of the box. So, for this single data point, performance scaled faster than clock rate, which is a nice change for all of us who experienced the P3 to P4 transition.
A minor error in the article was that beta was stopped by skin while alpha isn't. This is bassackwards.
Alpha particles (He nuclei stripped of their electrons) are the elephants of the radiation world. They are large and charged so they tend to interact with everything and are stopped by dead skin. You wouldn't want to ingest alpha emitters, however. The rem (roentgen equivalent man) is used to measure the potential damage of radiation. It coverts rads (which is the not incredibly useful "absorption of 100 ergs per 1 gram of material) to a more useful number. Alpha particles use a Q (quality) value of 20 or 30 (depending on which country you are in) which means that if the alpha particle gets to living tissue, it does a ton of damage.
Beta particles are either an electron or positron depending upon the reaction involved and are smaller and carry 1/2 the charge of an alpha particle so they interact less than alpha. They still interact fairly aggressively so clothing will stop beta (so wearing a watch with the tritium dial is ok but you wouldn't want to be the worker who licked her brush while painting the dial). Beta sources have a Q of about 1 which means that they don't do a lot of damage.
Neutrons carry no charge but are large, so they are the next most likely to interact with other matter. 10cm of dry air is enough to stop neutron flux. Neutrons have a Q of 3 to 10, depending upon their velocity (fast or thermal) and which country you are in.
Gamma radiation is an electromagnetic wave (like light, radar, &c) and carries no charge. It tends not to interact with matter which is why it is both difficult to build shielding -- even lead is nearly transparent of gamma rays in the "gamma ray window", which is somewhere around 2.3 MeV if I remember, which is particularly important with Cobalt-60 decay which releases 2 gamma rays at this energy level -- and why it is relatively harmless at low levels. Most gamma radiation has a Q of 1.
25 - 50 rem is the minimum one time exposure that will cause blood chemistry changes. Most people who live at sea level get 100 mrem per year from naturally occurring background sources (more if you are a frequent air traveler or live in Denver). Around 500 rem in a one time dose is LD 50/20 (half of those exposed will die within 20 days). National standards (as of 10 years ago, the last time I worked in this field) say that radiation workers can be exposed to up to a maximum of 5 rem per year.
Cheers!
Re:Cooling actually does speed up asynch CPUs
on
Clockless Computing
·
· Score: 1, Flamebait
He's totally making this shit up. Everyone knows that early 90's Caltech research into async computing was doomed since Professor Apgar was funneling NSF funds into his "do-undergrads-in-my-hew-hot-tub" fund and the grad students were spending all their time in beanbag chairs huffing nitrous and finding new uses for superglue. I doubt anyone from that lab even remembers 1993, let alone details about the test harness or latch design.
Slashdot Mirror
Apparently Geekpatrol is hosted on a G4 Powerbook. Were it hosted on a Intellitosh it would have survived a bit longer.
You don't have to rotate the camera. You aren't thinking through the geometry of a photograph from hundreds of miles up.
Due to spacecraft (or aircraft) motion, stereo pairs are generated along the flightpath if sequential images overlap. In many systems, each image n generates overlap with both image n+1 and n+2. Given the ability to launch two cameras, why not launch a single camera with more capabilities? Another minor, and common, error is that the Cartosat-1 has a 2.5m pixel on its CCD, which does not transalate into a 2.5m "resolution." CCD resolution corresponds to Ground Sampled Distance (GSD), or the amount of ground sampled on one pixel. Ground resolved distance, (GRD), measures the highest frequency visible in the image and is what we normally think of as "resolution." As a result, for electro optical systems, GRD = 2 x GSD.
What the Clickable Culture story missed is that today's Wall Street Journal reported that the Second Life resident has sold the real world publishing rights of Tringo to Sean Ryan's Donnerwood Media for "low five figures." They plan to publish Tringo for mobile phones and on the web. Also mentioned over at Terra Nova.
"A spacecraft equipped with a telescope would trail tens of thousands of miles behind the starshade to collect and process the light." How about reading the article (all 297 words) before posting?
1) The research will only go forward with more funding 2) SRI International is involved ("No, really, Uri Geller *is* a psychic!") 3) "Mike McKubre from SRI International, in Menlo Park, Calif., a respected researcher who is influential among those pursuing cold fusion" is not the same as "Mike McKubre, a respected researched who is also working on cold fusion" 4) It's an election year and DOE, hardly a bastion of good science under Bush, is about to announce Cold Fusion is workable at a time of record world oil prices?
Second Life already has a vibrant economy driven by user-created content and some users are choosing to convert their in-world earnings back in US$ via Gaming Open Market. Terra Nova has extensive discussions of the strength of the SL economy, as well as some of the problems that can arise from using real-world currency in virtual worlds -- including resident alienation, loss of suspension of disbelief, and interesting legal implications. It is also somewhat specious to suggest that pulling real-world currency into a virtual world somehow enables user-created content. The billing system, whether in US$ or SL's L$, was certainly a complicated component of the overall product, but it was dwarfed by the complexities of 3D streaming, collaborative creation, and distributed physical simulation.
In a similar way, some Second Life users decided that they wanted to be able to play a traditional RPG within Second Life. The result of their creation was Dark Life, captured in SL's New World Notes. The Dark Lifers have been quite successful and have drawn many players into their game, including many new users. In addition to the usual creature killing, magic spells, healing and leveling, they have also introduced some very interesting twists on traditional RPG gameplay.
This discussion occurred in the afternoon/evening after State of Play. It was very interesting to learn about the rulemaking process. For those who aren't familiar with it, rulemaking is when government agencies convert policy decisions passed by congress ("reduce automobile emissions") into actual federal statutes ("all light trucks lines will reduce their average emissions by 5% by 2007"). Part of the rulemaking process is posting the proposed rules and then soliciting public comment. In the old system, these periods of feedback were announced via the Federal Register and feedback was submitted via snail mail. The result was that a small number of lobbyists and individuals who scoured the Register would submit feedback. The agency in charge of the new statute would then publish a response, and eventually, the new law. The government doesn't have to follow the feedback but is often influenced by multiple submissions with similar viewpoints. The new system (partially implemented) allows for automated searching of proposed rules and electronic responses. A requirement is that posting be anonymous. As readers of /. can see, this is a very gamable system. The lobbyists now have a cheap and easy way to scan all proposed rules for ones that touch on their area and a undetectable way to submit massive numbers of similar viewpoints from apparently multiple sources. The new system is supposed to make the system more democratic but the actual result is to make it less democratic. Somehow not at all shocking that the Wired article missed that.
Now, given that there were many smart game designers/developers in the room who've had experiences managing communities that are full of people who try to game systems, there were ideas put forth -- /. was even mentioned -- but the government folks who were there weren't particularly interested in hearing that there system was flawed. Instead they just wanted information on how to educate people about the new system.
It was an enlightening and terrifying view into how senior government employees attack problems.
Second Life has been hapily using NSIS -- featuring Super-PIMP(tm) technology -- for 3 years. We played with just about all of the different installers and settled on NSIS because it generated by far the fastest installs and also created the smallest files. Throw in the fact that it was incredibly easy to use and you had a winner. We haven't switched over to 2.0, though.
I can't speak to the standard, but I can cover our experiences using Jpeg2000. In early 2001, the Second Life team did an evaluation of available still image compression schemes in order to determine whether an off-the-shelf solution would meet our requirements of providing flawless visual reproduction at 10:1 compression while preserving chroma at compressions of 100:1 or more, allowing progressive streaming in order to handle level of detail and mipmapping, and be high performance enough to allow for multiple packet decodes per game frame. We went into the search assuming that we would end up having to write out own compression scheme and were pleasantly surprised by the performance of Jpeg2000. We selected the Kakadu libraries for Jpeg2000 compression and decompression and have been happily using them for 3 years on Linux, Mac, and Windows.
It is a shame that Jpeg2000 hasn't seen wider adoption, as it is visually far superior to Jpeg at similar compression levels, especially in reduced "ringing" around high-frequency edges, and its ability to handle progressive streaming is incredibly useful in interactive environments. In Second Life's case, images as large as 2048x2048 are delivered interactively to the client viewer, with a single packet providing enough detail for distant textures. As the user approaches textures, additional packets are delivered to the client, providing a progressive increase in detail with very low latency, thanks to Jpeg2000's ability to deliver fine-grained increases. Kakadu's high performance has also been critical, since many scenes in Second Life have thousands of different textures in view because of user created and uploaded textures.
The "hacking your metabolism" argument is not well defended by the research. However, the constraints of not eating carbos does tend to reduce your caloric intake, leading to weight loss.
For a college engineering course we had to do some massive analysis of an analog feedback control system. For the assignment we were supposed to use MATLAB running on our VAX 11/780 cluster. I had the (then very new and uber-cool) HP 28S clamshell so I programmed the various matrix operations into it and then went to the computer lab late at night race the cluster. I don't remember the exact numbers but the HP finished in many seconds while MATLAB spun for many minutes which I remembered thinking was pretty amazing.
For what it's worth, at WWDC the Blizzard guys said that Warcraft 3 was running around twice as fast on the dual 2GHz G5 as on a dual 1.4GHz G4, and that it ran out of the box. So, for this single data point, performance scaled faster than clock rate, which is a nice change for all of us who experienced the P3 to P4 transition.
A minor error in the article was that beta was stopped by skin while alpha isn't. This is bassackwards. Alpha particles (He nuclei stripped of their electrons) are the elephants of the radiation world. They are large and charged so they tend to interact with everything and are stopped by dead skin. You wouldn't want to ingest alpha emitters, however. The rem (roentgen equivalent man) is used to measure the potential damage of radiation. It coverts rads (which is the not incredibly useful "absorption of 100 ergs per 1 gram of material) to a more useful number. Alpha particles use a Q (quality) value of 20 or 30 (depending on which country you are in) which means that if the alpha particle gets to living tissue, it does a ton of damage. Beta particles are either an electron or positron depending upon the reaction involved and are smaller and carry 1/2 the charge of an alpha particle so they interact less than alpha. They still interact fairly aggressively so clothing will stop beta (so wearing a watch with the tritium dial is ok but you wouldn't want to be the worker who licked her brush while painting the dial). Beta sources have a Q of about 1 which means that they don't do a lot of damage. Neutrons carry no charge but are large, so they are the next most likely to interact with other matter. 10cm of dry air is enough to stop neutron flux. Neutrons have a Q of 3 to 10, depending upon their velocity (fast or thermal) and which country you are in. Gamma radiation is an electromagnetic wave (like light, radar, &c) and carries no charge. It tends not to interact with matter which is why it is both difficult to build shielding -- even lead is nearly transparent of gamma rays in the "gamma ray window", which is somewhere around 2.3 MeV if I remember, which is particularly important with Cobalt-60 decay which releases 2 gamma rays at this energy level -- and why it is relatively harmless at low levels. Most gamma radiation has a Q of 1. 25 - 50 rem is the minimum one time exposure that will cause blood chemistry changes. Most people who live at sea level get 100 mrem per year from naturally occurring background sources (more if you are a frequent air traveler or live in Denver). Around 500 rem in a one time dose is LD 50/20 (half of those exposed will die within 20 days). National standards (as of 10 years ago, the last time I worked in this field) say that radiation workers can be exposed to up to a maximum of 5 rem per year. Cheers!
He's totally making this shit up. Everyone knows that early 90's Caltech research into async computing was doomed since Professor Apgar was funneling NSF funds into his "do-undergrads-in-my-hew-hot-tub" fund and the grad students were spending all their time in beanbag chairs huffing nitrous and finding new uses for superglue. I doubt anyone from that lab even remembers 1993, let alone details about the test harness or latch design.