Yes, but H.265 is a video compression format. I dont't think they are going to take videos with the OSIRIS camera (or any of the other instruments) nor transmit video data back to earth.
Anyway, after some googling one finds that the most advanced image compression formats are based on some form of wavelet transform. Examples would be JPEG 2000, JPEG LS and ICER. All of them predate 2004 but have seen some improvement over the last years. ICER was used on the mars exploration rovers, so it could be they use something similar on the rosetta probe. Their compression rates are all very similar and differ only in their compational efficiency. Some comparisons can be found in this paper and here (homepage of the MRP Format (Minimum-Rate Predictors), which marginally outperforms JPEG formats but only on 8bit grayscale images). The latter also compares against JPEG XR or HD Photo from Microsoft which was released in 2009 but seems to perform worse than JPEG-LS.
I don't see any advances in still image compression since 2004 that I would describe as huge, but that view is just based on a quick internet research. I'd be happy to change my mind on this. Maybe NASA or ESA have been working on something much better and I just missed it (I didn't check patent databases).
Excuse my ignorance but I'm curious about these "huge" advances in compression technology. Can you give an example of a particular compression algorithm that hasn't been around in 2004 and is much better than the most commonly used formats (i.e. jpeg) ?
Meanwhile annual death rates continue to fall every year. We still have about a month to go but it looks like 2013 will see the lowest number of air traffic casualities since the beginning of world war 2: Casualties since 2010
I wonder if that is because of more and more automation or despite of it?
One possible intuitive explanation (at least for myself) is to imagine a system where its particles cannot exceed a maximum energy (a energy ceiling if you will). Imagine for example a one dimensional gas where its particles can reach but not exceed a certain velocity or kinetic energy (unlike the fundamental limit of light speed where the particle can approach c but not reach it while its energy goes to infinity). If you put energy into such a system starting from a low energy state, where all particles are initially thermally distributed over many different velocities, the particles will start to reach the energy ceiling until all particles have the same maximum velocity. Obviously as all particles now have the same maximum velocity the system is in a state with maximum order (or lowest entropy). So by putting energy E into the system we reduced the entropy S, in mathematical terms dS/dE0 or in other words the system had a negative temperature right before the highest energy was reached.
Same for me. I saw my first porn at the age of 5 or 6. Some friend from kindergarden brought his dads magazines to the playground. I have to admit I was kind of shocked when I saw it. My parents were totally cool with it, but for me it was odd to realize my parents were doing the same things (it didn't occure to me that what they were doing was probably very boring and awkward compared to porn). Anyway growing up you will experience several visual shock moments: first porn pictures, first horror movie, first porn film, first videos of real gore and violence You see it, you're shocked, you get over it (and hopefully maintain your sanity).
Symbotic is an U.S. based company. The robots used in the factory, are developed in the U.S. by mostly american hard- and software engineers. That's real jobs right there! I think it's sad that here on slashdot (a site for nerds which for me means scientists and engineers) news of an automated factory is received with such negativity. Shouldn't we be amazed about the fact that we can actually built a fully automatic factory? I mean those robots need to be programmed by someone, right?
Instead we bitch and moan about factory workers losing their jobs, I mean, what is this Slashdot bad news for blue collar workers ?
Solar cells with 1kW/sqm? How is that possible without using focused sun light? The solar constant is ~1300 kW/sqm outside earths atmosphere and around 740 kW/sqm on the ground (on the equator). Solar cells with 100% (or more:)) efficiency don't exist (last time I checked it was around 30%).
Actually to me it seemed almost too fast. Robotic arm capture in under 3 minutes (from the video) thats a short time considering all the things that could go wrong: -crash into the berthing structure of the dragon module destryoing it->abort docking, loose all the cargo (sorry guys, no food for next month), huge loss for SpaceX -while crashing into dragon destroy the arm itself->wait several months at least for replacement->no dragon resupply missions anymore->SapceX losses major contract->SpaceX goes out of business->1000+ people loose their jobs...
If I were the guy controlling that arm I would have done it much slower and afterwards would have to take a long shower...
By the way nowadays almost all physics papers can be found as a preprint on arxiv, the difference to the puplished version is usually not significant for the layman.
Anyway, the main application of this is that you can use it to prepare entangled pairs of qubits to be used in various quantum secure communication schemes.
First one is from 1968. I know it is a bit pessimistic but this seems like the skin tight space suit is one of those perpetual tech dreams (alongside flying cars, fusion power plants, space elevators, hypersonic aircraft etc.) where once in a while someone comes up and says that we have the technology now or is just around the corner (only wait for 5 more years...). From looking at the history of technological innovation one realizes that if some new technology takes longer than at most 5 years to be turned into a promising(!) prototype chances are it will never ever really work (but will still be funded because the potential benefits are so huge).
Ah you know what I just looked up the history of the jet engine (Timeline of jet power) and realized it took almost 40 years from the first prototype to the first jet powered aircraft, so scratch the above comment.
Well as I said you must be the weird guy. First of all I never mentioned that smelling bad is the problem and I'd like you to point me to scientific evidence that shows that there is a relation between the odor of sweat and lifestyle and eating habits (and I'd happily change my mind about that). And second of all I find your advice of dressing accordingly rather funny. Would you like me to go to the office in my underwear or what? I have no problem doing that at home, but when there are 20 people in a room they on average release 20*40W=800W of heat energy that you need to get rid of. Healthy lifestyle or not that's just not comfortable after a while.
And by the way thank you for implying I smell bad, I mean that was some brilliant deduction from my answer (wtf?) and suggests that you seem to have had problems with that in the past (maybe a girlfriend or two pointed that out) and that made you change your lifestyle so that you are not so socially isolated. You probably are also one of those people who jog through the city for the sole purpose of loosing weight so that the women folk will like you more. Your just pathetic!
Man, you must be the weird unpopular guy at your office and I'm sure your coworkers all agree with you that it is absolutely brilliant having to sit 8 hours a day in a nice cozy 30C office especially in a meeting with 20 other people in the room all sweating their asses off. I live in the south part of germany and every summer I am asking myself why we don't have air conditioned houses here like they have in the US. I quite envy the US in this respect. I once stayed in Florida for 3 weeks and every hotel room and house had full air conditioning and I thought to myself this is paradise! The company I work for (in Munich) has an air conditioning system where cold groundwater is pumped through the building to cool it down. I don't think I could be very productive at 35C inside, also a lot of Computers would get problems with their thermal management. Apart from that we build sensitive electronics, so we actually need stable temperatures.
Anyway I'd gladly trade some of our supposedly superior infrastructure for a little bit of US air conditioning. Travelled with german trains lately? Maybe IC or ICE? They have those brilliant AC systems designed for max. 30C outside which means they regularly fail during hot summer days exactly when you'd need them. It is totally brilliant to sit uncomfortably in a train fully packed with hundreds of people for 3 hours with 33C outside and the AC is not working. You'd think that the third most powerful economy in the world could build trains with some decent AC, but no. I guess that is because of people like you who think that it costs to much power what with our nuclear power plants switched off and all. But that is a whole different chapter in the book of recent german/european sociopolitical decisions of utter brilliance (dumping hundreds of billions of euros in essentially fucked up southern european economies would be another great one). But I better stop now before I wander of into pointless political rant and use the word 'brilliant' too often.
The rocket launch animation in the video does not show the Falcon 9 rocket+Dragon but the not yet fully developed Falcon 9 Heavy (SpaceX) which according to the SpaceX launch manifest will have a first test launch later this year (but I guess late 2013 seems more likely judging from SpaceX's previous track record of delays).
But it should probably be mentioned that his dream died long before he did (which was in 2008 by the way). Their first planned satellite NEAP (Near earth asteroid prospector) would have landed on an asteroid and claimed it as SpaceDev property but they ran into funding problems and cancelled the project. As subsidiary of the Sierra Nevada Corporation they are currently building the dream chaser spacecraft.
As for the plans of Planetary Resources Inc. the only way I see this failing is that the investors pull out after 4-5 years when they are going to realize that it will be far more expensive than originally thought and they'll get annoyed at the amount of red tape they have to wade through in order to get a clearance for earth orbit insertion of an asteroid. So probably very likely!
Can he just delay by one week? There are only small launch windows for Cape Canaveral launches to ISS. Does somebody know the approximate window size for a Falcon 9+Dragon launch to ISS? Also from this ISS launch schedule, there is a launch of a soyuz at may 15th so if he delays too much, he will probably have to move the launch date back by at least a month.
I wonder what the requirements are at NASA versus SpaceX concerning mission failure probabilities? Reaching a 90% chance of success is probably easy but 99.99% chance of success is much harder. And then you could ask if NASA or SpaceX has such high requirements why didn't SpaceX plan accordingly? Are they forced to promise early launch dates to keep investors?
I don't know about the details of the recent embargo enacted for Iran, but I would guess that if any component could be used to build high tech weapon- or reconnaissancesystems nobody is allowed to export it to Iran. On the other hand China will probably supply all these things with or without embargo. Sorry I'm too lazy to look it up on wikipedia, maybe someone here knows more about this?
Interesting, obviously I didn't know this one. Always revealing to realize that most of the things we argue about today have been discussed over and over again by previous generations.
Even if you consider that the destruction is not in your own country or economy (so that one might think one does not need to bear the cost of repair) it will eventually be coming back to bite you in other forms (take the emerging poppy trade as a result of the afghanistan war and the resulting increased trug trafficking as an example) .
But then strictly speaking the money spent on wars is not really wasted. It is used to pay wages, buy weapons, invest in military research. Military personal then put the money back into the economy when spending the money on houses, cars, laptops, smartphones etc. Engineers, mechanics and so on are payed to design and build the weapons who in turn get payed for it. Even the fuel wasted by the military is bought from the oil companies who in turn buy new oil drilling platforms which have to be designed and manufactured by engineers and technicians.
The idea that a lot of the technology comes from the space programming is mostly a myth. Take Teflon for example,discovered in 1938, used as corrosion protection in the Manhattan project in 1943 then in 1954 first applied to kitchen products long before sputnik.
The problem is that you can't expect people to be excited or involved in something that ultimately influences them only very little. People are concerned with their own survival (which in todays world becomes more and more expensive) and not everybody can be a spacecraft engineer or scientist. The main interest of humans has always been to have work and be able to support themselves and their families and if the military-industrial complex provides that you can't blame them for trying to defend it.
We space enthusiasts were lucky for a while that space exploration was fueled by the cold war, when defense interests overlapped with space exploration interests. Without the "need" for ICBMs we would never have built any orbit capable rockets at all.
I mean how do you justify sending a space probe to the heliopause to the common taxpayer? "Please give us your money so that a couple of scientists and graduate students will be able to publish some papers and advance their careers in about 25 years?" Even among the scientific community the (real) interest for heliopause research is probably very small. The timescales of such projects are just too long. A heliopause probe would take maybe 5 years to develop and another 20 years to reach its destination. That's almost the duration of a typical research career, nobody working in science can afford to wait that long for any results.
The way I see it is, that it is not yet the time for such research. Just like 16th century physicists would not have been able to learn something of subnuclear particles as the technology was not available at the time, we today have to wait for a significant amount of space exploration before we can properly investigate the outer regions of our solar system. Once we have research outposts on Titan or Pluto that can send their own probes to the oort cloud this sort of research will be much more affordable and simpler. Alternatively we have to wait for better space propulsion technology so that we can sent those probes faster to their destination.
In the meantime I'm not particulary worried that we will descent into savagery again (at least technology wise). The average citizen has grown too fond of their little tech gadgets and other helpers for everyday lives to just throw it all away. We are at a stage where we will defend with all our strength the right to access the internet and so on and so forth. The time for proper space exploration will come just maybe not in our lifetimes...
The main point of a quantum network is to produce entangled qubit pairs and to store them long enough to use them. With 99.8% failure rate you just have to try 500 times and do it faster than your decay rate (which is easy). Once you succeed, the important figure of merit is your state fidelity (how close the real state is to the desired ideal state). Here they report around 85% fidelity. Which means that if you create 100 entangled pairs 85 of them will be pure (in the sense that any subsequent operation with them, like a teleportation, will work). This not too bad, but not the best in the field. There are so called entanglement purification protocols with which you can filter out the bad apples and get almost 100% fidelity.
The entanglement procedure relies on the polarization of the photons. What they do is to apply some light pulse to atom A which prepares its state into either one of two possible states (qubit A 0 or 1). As long as you don't measure it, the atom is in a superposition of those two state (so you cannot even in principle say whether it is 0 or 1). However depending on this state the photon emitted from atom A during the state preparation will have a specific polarization (so before you measure qubit A the photon will be a superposition of two polarizations). This photon after going through the fiber will be absorbed (with 0.5% probability) by atom B and depending on the polarization this will prepare this atom in either of two states as well (this is then qubit B 0 or 1), but as the polarization is not yet determined qubit B will also be in a superposition of 0 and 1 (again you can't even in principal know the state before measuring). Now qubit A and B are entangled because if you measure either atom A or atom B it will automatically determine the state of the other atom as well.
(Disclaimer: IAAP) This is actually not the first realization of a quantum network, that's not the point. Chinese and other researches have already created a quantum network link over up to 16km distance (see for example here: Experimental free-space quantum teleportation (only abstract)). Allthough strictly speaking this was only a 2-point link. A quantum repeater which is elementary part of a quantum network has also been demonstrated with atomic ensembles.
The new thing here is that their quantum repeater used a single atom in an optical cavity as a photon storage device. The advantage of using only a single atom as qubit storage is the potentially much longer storage time compared to a group of atoms but it is much more difficult to get enough coupling strength to the photon. This is why they use a cavity which is resonant with the atomic transition used in their setup. But even then you only successfully write a photon in 0.5% of all tries. But that doesn't actually matter, all you need is to establish an entangled pair before your storage time runs out, so you just to need to repeat the write attempts fast enough.
To clarify: the applications are in quantum key distribution, distribution of entangled qubits for quantum computing purposes, it cannot be used for FTL communication, if ever it will be a very long time before this can be used for superior data transfer (look up quantum dense coding).
This is all basic research to learn how to handle single atoms, how to couple them to photons (so that you can use optical fiber networks) and how to increase fidelity of state preparation and storage time (the stronger you make the coupling to the photons the faster any quantum state will decay due to coupling to the environment). But the main purpose is (to be as cynical as possible) to advance the careers of the principal scientists involved, ensure the flow of grant money and produce phds:) Seriously the setups they use (ultra high vaccuum, laser cooling etc.) will NEVER be used in any commercial application. You'd need some sort of solid state device where the physics is quiet different and you'd have to do the research all over again.
Well I probably shouldn't have used the word monkey... But I let's be honest, wouldn't it be better? 3D doesn't add any new creative content to a movie, it's a gimmick. And as such the engineer in me was hoping for something like this: Me: "That is some pretty awesome stuff you have there, guys! So how did you do it?" Guys from Stereo D: "Well, you see, we developed this very simple but clever theory and derived this nice little formula here. We then put this formula into our software and voila, 3D conversion! And by the way you can now buy this software do this with all your movies!" You know, so that the work those people did was not to go through every frame themselves but design the software to do it for them. Don't you think it is more impressive to design and build the robot that builds your house automatically instead of building the house yourself? If the house is supposed to be a piece of art then the answer would probably be no, but in this case the original movie was the piece of art, while the 3D conversion was not (it doesn't add any new creative content).
I am a little disillusioned by the article to be honest. It was always clear to me that once you know the depth of every pixel in a movie frame, turning this depth information into a parallax projection is the trivial part (just like once you know the color of a texture in a B&W film, actually putting that color into each frame is easy). The hard part is getting the depth or the color in the first place. So I always thought (or the nerd in me hoped) those studios had some kind of awesome general algorithm or technique with which they extract depth information from the 2D image (in case of 3D conversion) or color information from the pixel grey value (in case of b&w colorization).
The reality is, that there is no such technology. When filming a scene in 2D the depth information is lost in the projection process. There are some tricks you can use: (a) using depth of focus (from gaussian beam theory you can relate the distance from the focus to the spot size), (b) relative movement of objects (closer objects move faster over the frame than more distant objects) (c) and the brightness (further away=darker). But these don't work in general only in special situations, (a) requires a small scene with small depth of focus so that you can see the varying sharpness of objects, (b) only works in situations where movement is linear for example (in a rotating setting like in Matrix, more distant objects move faster) and (c) I guess depends on the illumination of the scene.
To summarize: the studios basically just hire an army of frame monkeys to painstakingly go through every frame using one of the technique (a),(b),(c) (or combinations thereof) or just use the intended distance from the original production (they know how far the camera was away from the object) and paint the depth map pixel by pixel over the frame until it looks realistic. I should have known really, if there was an algorithm that works in general all you'd have to do is to load the movie into a supercomputer wait a few hours and get the 3D version back. It would be dirt cheap and everyone could do it at home:). Come to think of it even with such a general algorithm you'd still need some QA guy going through every frame to make sure it looks good (so instead you need an army of QA frame-checker monkeys and you're back at square one).
The article mentions that at a resolution of 8000x4000 you need a triangle rate of at most 40 billion triangles per second to render your scene perfectly quoting the shannon sampling theorem. Probably I'm just missing something here but how does he arrive at that number?
I'm guessing he argues that you have to process 8000*4000*72FPS=2.3 billion pixels per second and the smallest possible triangle would be 1 pixel sized, so that you need a triangle rate of at most 2.3 billion/sec.
Now there are two levels of sampling going on here. First you use triangles to sample reality (not actually a sampling more an approximation) and then you sample those triangles with the pixels on your screen. The shannon theorem says that with a maximum bandwith/max. frequency in your scene of fmax you need at most a sample rate of 2*fmax. The resolution then gives you maximum frequencies of 1/4000 in one direction and 1/2000 in the other. These are the highest frequencies you can sample in your scene. With the triangles you can now approximate these frequencies, which will always give an infinite bandwidth (i.e. spectrum of a saw tooth function). To perfectly approximate these frequencies you need an infinite number of triangles but it doesn't make sense to make them smaller than 1 pixel.
I mean, basically you don't even need Shannon here, it's 1 pixel =1 triangle, right?
So how does he get from 2.3 to 40 billion?
Slashdot Mirror
Yes, but H.265 is a video compression format. I dont't think they are going to take videos with the OSIRIS camera (or any of the other instruments) nor transmit video data back to earth.
Anyway, after some googling one finds that the most advanced image compression formats are based on some form of wavelet transform.
Examples would be JPEG 2000, JPEG LS and ICER. All of them predate 2004 but have seen some improvement over the last years. ICER was used on the mars exploration rovers, so it could be they use something similar on the rosetta probe.
Their compression rates are all very similar and differ only in their compational efficiency. Some comparisons can be found in this paper and here (homepage of the MRP Format (Minimum-Rate Predictors), which marginally outperforms JPEG formats but only on 8bit grayscale images).
The latter also compares against JPEG XR or HD Photo from Microsoft which was released in 2009 but seems to perform worse than JPEG-LS.
I don't see any advances in still image compression since 2004 that I would describe as huge, but that view is just based on a quick internet research. I'd be happy to change my mind on this.
Maybe NASA or ESA have been working on something much better and I just missed it (I didn't check patent databases).
Excuse my ignorance but I'm curious about these "huge" advances in compression technology. Can you give an example of a particular compression algorithm that hasn't been around in 2004 and is much better than the most commonly used formats (i.e. jpeg) ?
Meanwhile annual death rates continue to fall every year.
We still have about a month to go but it looks like 2013 will see the lowest number of air traffic casualities since
the beginning of world war 2:
Casualties since 2010
I wonder if that is because of more and more automation or despite of it?
One possible intuitive explanation (at least for myself) is to imagine a system where its particles cannot exceed a maximum energy (a energy ceiling if you will). Imagine for example a one dimensional gas where its particles can reach but not exceed a certain velocity or kinetic energy (unlike the fundamental limit of light speed where the particle can approach c but not reach it while its energy goes to infinity).
If you put energy into such a system starting from a low energy state, where all particles are initially thermally distributed over many different velocities, the particles will start to reach the energy ceiling until all particles have the same maximum velocity.
Obviously as all particles now have the same maximum velocity the system is in a state with maximum order (or lowest entropy). So by putting energy E into the system we reduced the entropy S, in mathematical terms dS/dE0 or in other words the system had a negative temperature right before the highest energy was reached.
Same for me. I saw my first porn at the age of 5 or 6. Some friend from kindergarden brought his dads magazines to the playground. I have to admit I was kind of shocked when I saw it. My parents were totally cool with it, but for me it was odd to realize my parents were doing the same things (it didn't occure to me that what they were doing was probably very boring and awkward compared to porn).
Anyway growing up you will experience several visual shock moments:
first porn pictures, first horror movie, first porn film, first videos of real gore and violence
You see it, you're shocked, you get over it (and hopefully maintain your sanity).
Symbotic is an U.S. based company. The robots used in the factory, are developed in the U.S. by mostly american hard- and software engineers. That's real jobs right there!
I think it's sad that here on slashdot (a site for nerds which for me means scientists and engineers) news of an automated factory is received with such negativity.
Shouldn't we be amazed about the fact that we can actually built a fully automatic factory? I mean those robots need to be programmed by someone, right?
Instead we bitch and moan about factory workers losing their jobs, I mean, what is this Slashdot bad news for blue collar workers ?
Now come on, mod me down.
Solar cells with 1kW/sqm? How is that possible without using focused sun light? The solar constant is ~1300 kW/sqm outside earths atmosphere and around 740 kW/sqm on the ground (on the equator).
Solar cells with 100% (or more:)) efficiency don't exist (last time I checked it was around 30%).
Actually to me it seemed almost too fast. Robotic arm capture in under 3 minutes (from the video) thats a short time considering all the things that could go wrong: ...
-crash into the berthing structure of the dragon module destryoing it->abort docking, loose all the cargo (sorry guys, no food for next month), huge loss for SpaceX
-while crashing into dragon destroy the arm itself->wait several months at least for replacement->no dragon resupply missions anymore->SapceX losses major contract->SpaceX goes out of business->1000+ people loose their jobs
If I were the guy controlling that arm I would have done it much slower and afterwards would have to take a long shower...
Here is the link to the paper on arxiv without paywall:
Quantum teleportation using active feed-forward between two Canary Islands
By the way nowadays almost all physics papers can be found as a preprint on arxiv, the difference to the puplished version is usually not significant for the layman.
Anyway, the main application of this is that you can use it to prepare entangled pairs of qubits to be used in various quantum secure communication schemes.
Her website shows a list of papers on this subject:
www.elasticspacesuit.com/documentation/
First one is from 1968. I know it is a bit pessimistic but this seems like the skin tight space suit is one of those perpetual tech dreams (alongside flying cars, fusion power plants, space elevators, hypersonic aircraft etc.) where once in a while someone comes up and says that we have the technology now or is just around the corner (only wait for 5 more years...).
From looking at the history of technological innovation one realizes that if some new technology takes longer than at most 5 years to be turned into a promising(!) prototype chances are it will never ever really work (but will still be funded because the potential benefits are so huge).
Ah you know what I just looked up the history of the jet engine (Timeline of jet power) and realized it took almost 40 years from the first prototype to the first jet powered aircraft, so scratch the above comment.
Well as I said you must be the weird guy. First of all I never mentioned that smelling bad is the problem and I'd like you to point me to scientific evidence that shows that there is a relation between the odor of sweat and lifestyle and eating habits (and I'd happily change my mind about that).
And second of all I find your advice of dressing accordingly rather funny. Would you like me to go to the office in my underwear or what?
I have no problem doing that at home, but when there are 20 people in a room they on average release 20*40W=800W of heat energy that you need to get rid of.
Healthy lifestyle or not that's just not comfortable after a while.
And by the way thank you for implying I smell bad, I mean that was some brilliant deduction from my answer (wtf?) and suggests that you seem to have had problems with that in the past (maybe a girlfriend or two pointed that out) and that made you change your lifestyle so that you are not so socially isolated.
You probably are also one of those people who jog through the city for the sole purpose of loosing weight so that the women folk will like you more.
Your just pathetic!
Man, you must be the weird unpopular guy at your office and I'm sure your coworkers all agree with you that it is absolutely brilliant having to sit 8 hours a day in a nice cozy 30C office especially in a meeting with 20 other people in the room all sweating their asses off. I live in the south part of germany and every summer I am asking myself why we don't have air conditioned houses here like they have in the US. I quite envy the US in this respect. I once stayed in Florida for 3 weeks and every hotel room and house had full air conditioning and I thought to myself this is paradise!
The company I work for (in Munich) has an air conditioning system where cold groundwater is pumped through the building to cool it down. I don't think I could be very productive at 35C inside, also a lot of Computers would get problems with their thermal management. Apart from that we build sensitive electronics, so we actually need stable temperatures.
Anyway I'd gladly trade some of our supposedly superior infrastructure for a little bit of US air conditioning. Travelled with german trains lately? Maybe IC or ICE? They have those brilliant AC systems designed for max. 30C outside which means they regularly fail during hot summer days exactly when you'd need them.
It is totally brilliant to sit uncomfortably in a train fully packed with hundreds of people for 3 hours with 33C outside and the AC is not working. You'd think that the third most powerful economy in the world could build trains with some decent AC, but no. I guess that is because of people like you who think that it costs to much power what with our nuclear power plants switched off and all. But that is a whole different chapter in the book of recent german/european sociopolitical decisions of utter brilliance (dumping hundreds of billions of euros in essentially fucked up southern european economies would be another great one).
But I better stop now before I wander of into pointless political rant and use the word 'brilliant' too often.
The rocket launch animation in the video does not show the Falcon 9 rocket+Dragon but the not yet fully developed Falcon 9 Heavy (SpaceX) which according to the SpaceX launch manifest will have a first test launch later this year (but I guess late 2013 seems more likely judging from SpaceX's previous track record of delays).
But it should probably be mentioned that his dream died long before he did (which was in 2008 by the way). Their first planned satellite NEAP (Near earth asteroid prospector) would have landed on an asteroid and claimed it as SpaceDev property but they ran into funding problems and cancelled the project. As subsidiary of the Sierra Nevada Corporation they are currently building the dream chaser spacecraft.
As for the plans of Planetary Resources Inc. the only way I see this failing is that the investors pull out after 4-5 years when they are going to realize that it will be far more expensive than originally thought and they'll get annoyed at the amount of red tape they have to wade through in order to get a clearance for earth orbit insertion of an asteroid. So probably very likely!
Can he just delay by one week? There are only small launch windows for Cape Canaveral launches to ISS. Does somebody know the approximate window size for a Falcon 9+Dragon launch to ISS? Also from this ISS launch schedule, there is a launch of a soyuz at may 15th so if he delays too much, he will probably have to move the launch date back by at least a month.
I wonder what the requirements are at NASA versus SpaceX concerning mission failure probabilities? Reaching a 90% chance of success is probably easy but 99.99% chance of success is much harder.
And then you could ask if NASA or SpaceX has such high requirements why didn't SpaceX plan accordingly? Are they forced to promise early launch dates to keep investors?
I don't know about the details of the recent embargo enacted for Iran, but I would guess that if any component could be used to build high tech weapon- or reconnaissancesystems nobody is allowed to export it to Iran. On the other hand China will probably supply all these things with or without embargo.
Sorry I'm too lazy to look it up on wikipedia, maybe someone here knows more about this?
Someone asked how the water production rate depends on air humidity. Here is a link to the datasheet of the WMS1000 from their website.
Depending on the available power the production rate drops to 350-550 liters/day in desert area with average relative air humidity of 30-35%.
There is also a neat picture of its internal components.
Interesting, obviously I didn't know this one. Always revealing to realize that most of the things we argue about today have been discussed over and over again by previous generations.
Even if you consider that the destruction is not in your own country or economy (so that one might think one does not need to bear the cost of repair) it will eventually be coming back to bite you in other forms (take the emerging poppy trade as a result of the afghanistan war and the resulting increased trug trafficking as an example) .
But then strictly speaking the money spent on wars is not really wasted. It is used to pay wages, buy weapons, invest in military research. Military personal then put the money back into the economy when spending the money on houses, cars, laptops, smartphones etc. Engineers, mechanics and so on are payed to design and build the weapons who in turn get payed for it.
Even the fuel wasted by the military is bought from the oil companies who in turn buy new oil drilling platforms which have to be designed and manufactured by engineers and technicians.
The idea that a lot of the technology comes from the space programming is mostly a myth. Take Teflon for example,discovered in 1938, used as corrosion protection in the Manhattan project in 1943 then in 1954 first applied to kitchen products long before sputnik.
The problem is that you can't expect people to be excited or involved in something that ultimately influences them only very little. People are concerned with their own survival (which in todays world becomes more and more expensive) and not everybody can be a spacecraft engineer or scientist.
The main interest of humans has always been to have work and be able to support themselves and their families and if the military-industrial complex provides that you can't blame them for trying to defend it.
We space enthusiasts were lucky for a while that space exploration was fueled by the cold war, when defense interests overlapped with space exploration interests. Without the "need" for ICBMs we would never have built any orbit capable rockets at all.
I mean how do you justify sending a space probe to the heliopause to the common taxpayer? "Please give us your money so that a couple of scientists and graduate students will be able to publish some papers and advance their careers in about 25 years?"
Even among the scientific community the (real) interest for heliopause research is probably very small. The timescales of such projects are just too long. A heliopause probe would take maybe 5 years to develop and another 20 years to reach its destination. That's almost the duration of a typical research career, nobody working in science can afford to wait that long for any results.
The way I see it is, that it is not yet the time for such research. Just like 16th century physicists would not have been able to learn something of subnuclear particles as the technology was not available at the time, we today have to wait for a significant amount of space exploration before we can properly investigate the outer regions of our solar system.
Once we have research outposts on Titan or Pluto that can send their own probes to the oort cloud this sort of research will be much more affordable and simpler.
Alternatively we have to wait for better space propulsion technology so that we can sent those probes faster to their destination.
In the meantime I'm not particulary worried that we will descent into savagery again (at least technology wise). The average citizen has grown too fond of their little tech gadgets and other helpers for everyday lives to just throw it all away. We are at a stage where we will defend with all our strength the right to access the internet and so on and so forth.
The time for proper space exploration will come just maybe not in our lifetimes...
The main point of a quantum network is to produce entangled qubit pairs and to store them long enough to use them. With 99.8% failure rate you just have to try 500 times and do it faster than your decay rate (which is easy). Once you succeed, the important figure of merit is your state fidelity (how close the real state is to the desired ideal state). Here they report around 85% fidelity. Which means that if you create 100 entangled pairs 85 of them will be pure (in the sense that any subsequent operation with them, like a teleportation, will work).
This not too bad, but not the best in the field. There are so called entanglement purification protocols with which you can filter out the bad apples and get almost 100% fidelity.
The entanglement procedure relies on the polarization of the photons. What they do is to apply some light pulse to atom A which prepares its state into either one of two possible states (qubit A 0 or 1). As long as you don't measure it, the atom is in a superposition of those two state (so you cannot even in principle say whether it is 0 or 1). However depending on this state the photon emitted from atom A during the state preparation will have a specific polarization (so before you measure qubit A the photon will be a superposition of two polarizations). This photon after going through the fiber will be absorbed (with 0.5% probability) by atom B and depending on the polarization this will prepare this atom in either of two states as well (this is then qubit B 0 or 1), but as the polarization is not yet determined qubit B will also be in a superposition of 0 and 1 (again you can't even in principal know the state before measuring).
Now qubit A and B are entangled because if you measure either atom A or atom B it will automatically determine the state of the other atom as well.
By the way here is a link to arxiv preprint:
An Elementary Quantum Network of Single Atoms in Optical Cavities
(Disclaimer: IAAP) This is actually not the first realization of a quantum network, that's not the point. Chinese and other researches have already created a quantum network link over up to 16km distance (see for example here: Experimental free-space quantum teleportation (only abstract)). Allthough strictly speaking this was only a 2-point link.
A quantum repeater which is elementary part of a quantum network has also been demonstrated with atomic ensembles.
The new thing here is that their quantum repeater used a single atom in an optical cavity as a photon storage device. The advantage of using only a single atom as qubit storage is the potentially much longer storage time compared to a group of atoms but it is much more difficult to get enough coupling strength to the photon.
This is why they use a cavity which is resonant with the atomic transition used in their setup. But even then you only successfully write a photon in 0.5% of all tries.
But that doesn't actually matter, all you need is to establish an entangled pair before your storage time runs out, so you just to need to repeat the write attempts fast enough.
To clarify: the applications are in quantum key distribution, distribution of entangled qubits for quantum computing purposes, it cannot be used for FTL communication, if ever it will be a very long time before this can be used for superior data transfer (look up quantum dense coding).
This is all basic research to learn how to handle single atoms, how to couple them to photons (so that you can use optical fiber networks) and how to increase fidelity of state preparation and storage time (the stronger you make the coupling to the photons the faster any quantum state will decay due to coupling to the environment). But the main purpose is (to be as cynical as possible) to advance the careers of the principal scientists involved, ensure the flow of grant money and produce phds:)
Seriously the setups they use (ultra high vaccuum, laser cooling etc.) will NEVER be used in any commercial application. You'd need some sort of solid state device where the physics is quiet different and you'd have to do the research all over again.
Well I probably shouldn't have used the word monkey... But I let's be honest, wouldn't it be better? 3D doesn't add any new creative content to a movie, it's a gimmick. And as such the engineer in me was hoping for something like this:
Me: "That is some pretty awesome stuff you have there, guys! So how did you do it?"
Guys from Stereo D: "Well, you see, we developed this very simple but clever theory and derived this nice little formula here. We then put this formula into our software and voila, 3D conversion! And by the way you can now buy this software do this with all your movies!"
You know, so that the work those people did was not to go through every frame themselves but design the software to do it for them.
Don't you think it is more impressive to design and build the robot that builds your house automatically instead of building the house yourself?
If the house is supposed to be a piece of art then the answer would probably be no, but in this case the original movie was the piece of art, while the 3D conversion was not (it doesn't add any new creative content).
I'm still on /. here, right?
I am a little disillusioned by the article to be honest. It was always clear to me that once you know the depth of every pixel in a movie frame, turning this depth information into a parallax projection is the trivial part (just like once you know the color of a texture in a B&W film, actually putting that color into each frame is easy).
The hard part is getting the depth or the color in the first place. So I always thought (or the nerd in me hoped) those studios had some kind of awesome general algorithm or technique with which they extract depth information from the 2D image (in case of 3D conversion) or color information from the pixel grey value (in case of b&w colorization).
The reality is, that there is no such technology. When filming a scene in 2D the depth information is lost in the projection process. There are some tricks you can use:
(a) using depth of focus (from gaussian beam theory you can relate the distance from the focus to the spot size),
(b) relative movement of objects (closer objects move faster over the frame than more distant objects)
(c) and the brightness (further away=darker).
But these don't work in general only in special situations, (a) requires a small scene with small depth of focus so that you can see the varying sharpness of objects, (b) only works in situations where movement is linear for example (in a rotating setting like in Matrix, more distant objects move faster) and (c) I guess depends on the illumination of the scene.
To summarize: the studios basically just hire an army of frame monkeys to painstakingly go through every frame using one of the technique (a),(b),(c) (or combinations thereof) or just use the intended distance from the original production (they know how far the camera was away from the object) and paint the depth map pixel by pixel over the frame until it looks realistic.
I should have known really, if there was an algorithm that works in general all you'd have to do is to load the movie into a supercomputer wait a few hours and get the 3D version back. It would be dirt cheap and everyone could do it at home:). Come to think of it even with such a general algorithm you'd still need some QA guy going through every frame to make sure it looks good (so instead you need an army of QA frame-checker monkeys and you're back at square one).
The article mentions that at a resolution of 8000x4000 you need a triangle rate of at most 40 billion triangles per second to render your scene perfectly quoting the shannon sampling theorem. Probably I'm just missing something here but how does he arrive at that number?
I'm guessing he argues that you have to process 8000*4000*72FPS=2.3 billion pixels per second and the smallest possible triangle would be 1 pixel sized, so that you need a triangle rate of at most 2.3 billion/sec.
Now there are two levels of sampling going on here. First you use triangles to sample reality (not actually a sampling more an approximation) and then you sample those triangles with the pixels on your screen. The shannon theorem says that with a maximum bandwith/max. frequency in your scene of fmax you need at most a sample rate of 2*fmax. The resolution then gives you maximum frequencies of 1/4000 in one direction and 1/2000 in the other. These are the highest frequencies you can sample in your scene. With the triangles you can now approximate these frequencies, which will always give an infinite bandwidth (i.e. spectrum of a saw tooth function). To perfectly approximate these frequencies you need an infinite number of triangles but it doesn't make sense to make them smaller than 1 pixel.
I mean, basically you don't even need Shannon here, it's 1 pixel =1 triangle, right?
So how does he get from 2.3 to 40 billion?