For an example of how this works, go into a mostly dark room with a camera. Have a look around. Turn on the camera, look straight into the flash as you fire it. Have a look around again.... Your wide-open pupils just let the full force of the flash in before you could blink, every receptor on your retina just fired, and it's going to be a few minutes before you can see anything again.
With a high enough power light source, this works just fine in daylight. I know this because I've flashed myself with a MIG welder - It was just a brief flash as I flicked the trigger at an inopportune moment, but the center of my vision was completely blank for several minutes. Simply turning off the machine and finding a safe place to sit down to wait for my vision to return was a challenge. I would have been screwed in a melee.
Anyway, no, goggles won't save you. If it's white light, you can't filter a narrow band like laser goggles. When welding with a shade 10 filter, when the arc is on, you can see what you're working on OK, but the arc itself is just white, completely clipping at the top of your eyes' sensitivity. When you turn the arc off, you're blind if you're indoors unless you have a 150 watt light inches away from what you're looking at. Outdoors you can just barely see what's going on, but at many angles the reflections of light leaking in from behind you overwhelm your forward vision (like with glossy screen laptops used outdoors, but worse). Using those kind of lenses will leave you blind anyway - they wouldn't need to flash you. Anything less and you'll still be vulnerable to the flash.
I think it's because of the hubris of calling it "awesome". Some people were bound to not like it, but being told it's awesome when you don't like it makes them feel like it's being forced on them by completely out of touch developers.
More specifically, people make very poor safety judgments on very rare, high-consequences events. For instance:
* Computerized flight envelope protection systems increase safety overall, but pilots balk at the idea that the computer is taking away some of their control
* Nuclear reactors have the best safety record of any large scale power generation technology, but people are terrified of them
* Pretty much anything the TSA does
And there are idiotic memes that just won't go away:
* People's belief that cell phones and WiFi will give them cancer, which holds up infrastructure deployments
* People disabling airbags and not using seat belts because they have a friend of a friend who got away unscathed without them
* Religion.:)
I'm a satisfied Crashplan user. I subscribe to the Crashplan Central service (They're calling it Crashplan+ Family Unlimited now), which means I get unlimited (Which appears to be *actually* unlimited, not Comcast-unlimited) backups to their disk farm in a bank vault in Minnesota. I get to back up all my computers - laptops, desktops, and even my personal VPS - all automatically, with staged version retention, and no hassles of running out of disk or other typical backups shenanigans. Totally does what it says.
I picked it because it: has unlimited seats so I can back up all my computers; it works on Linux, OSX, and Windows; and it has several security models, including "manually generate and install encryption keys on a per-machine basis, and make damn sure you back them up somewhere safe because we only have your encrypted data", which I use because it's compatible with my tinfoil hat.
One complaint: On my VPS, it creates some sort of cache that gradually grows to gigs in size. I suspect it's due to indexing the very large number of files that maildirs create. If it runs out of disk, the process starts consuming 100% CPU. Lame. So I have a cron job that shuts it down, blows away the cache, and restarts it periodically.
On the whole: Completely worth 600 pennies a month.
Review 2: My previous solution was BackupPC. I arrived at it after using similar but less refined backups like rsnapshot and dirvish. BackupPC was the best - you just have to throw lots of disk at it, and it does what it promises. If you can do cross-site backups, it's pretty damn good. The downsides were that you have to plan ahead to have enough disk, and the disk IO during backups was unexpectedly high.
I still occasionally make a manual copy of everything and leave it in a safe deposit box. Defense in Depth is a good thing.
Mods are where it's at. Boxed releases are meant to be easy for a broad audience, most of who can't handle teamwork.
PR is *brutal* on people who can't work as a team. Occasionally you get some dork who won't follow orders and just Rambos around. He quickly ends up without a squad. Soloing in PR sucks - long stretches of hiking with no action, then a well organized squad takes you out. They get frustrated with that routine pretty quickly and uninstall the mod, having decided it's lame. The ones that remain are fair to good.
I used to be in Bellum Aeternus on PlanetSide. We played the Vanu team (generally considered to be "hard mode" for PlanetSide, at least back then). The clan was great - coordinated assaults and organized defense can take out utter hordes of Terran / NC zerglings. Over the course of the day we'd completely take over most of the universe, triumphing even when the other two races would team up against us. I heard it fell apart eventually, though.
Long ago, it was lmctf (Loki's Minions CTF mod) for Quake 2. That was the most fun I've ever had. Again, lots of people who know the basics: Coordinated, communicating base defense organized at choke points; designated flag carriers and escorts carrying appropriate runes; people who understand and use sophisticated tactics. "ROAR!... This... is CNN."... You had to be there.:)
That depends on the game. If you're playing Quake-style deathmatch, sure, that kind of camping is lame.
I play things like Project Reality where the maps are enormous and the gameplay is much slower. You squad up and hike across the map for a good several minutes without any enemy contact (though you have to be constantly on your toes). You reach a river. The whole squad crossing at once is suicidal, so you go in pairs, with everyone else staying in the trees and ready to provide cover fire. With 30 seconds for each pair to cross the river, you're going to be sitting there watching your sector for a while. Constantly looking around to keep your mouse awake just makes you easier to see. When you see a muzzle flash on the far bank, you have to react fast: the shooter's already cycling in the next round, and he's sure to have friends. The 1 second it takes your mouse to wake up is an eternity when the guy crouching next to you just took one in the head.
If you live through that exercise and make it to the enemy base, the first part is easy: run in, blow away anyone who objects to your presence. But then you have to hold the territory until you achieve the capture, which means a couple minutes of hiding on the porch or behind some sandbags, holding your breath. It's not going to be a surprise attack: you know the reinforcements are coming; it's just a matter of when and where. Moving means you become the canary. Lag - including from your mouse - means you will let your squad down when half a dozen bad guys with assault rifles jump out of the alley.
* An ergonomic shape to hold for a couple hours at a time. I find that it works well to have a more arched shape for continuous use, instead of a flatter shape for reaching over to occasionally click something. Thumb rests are also popular.
* Lots of buttons, in a convenient arrangement.
* High resolution. Even if you don't want it to track fast, you want the tracking quantum to be small. For productivity apps, on the other hand, a larger quantum is nice to prevent it from accidentally moving.
There are also firmware differences. Ever notice how the LED goes dim when you're idling? That's a power saving strategy. It's actually just flashing it on occasionally to see if it's moved, then going back to sleep. Cordless productivity mice do this very aggressively, and you *will* miss that golden headshot opportunity if your mouse is idled down, since it won't start tracking again until the next flash - which can be as infrequent as once every couple seconds if you've been camping a while and it's gone into deep sleep.
TFA is measuring performance of speed clicking a bunch of icons. The mouse will never go to sleep in this scenario. If they tried another benchmark - like, hold still for 30 seconds and then click the icon as fast as you can - you will see some BIG differences, and gaming mice that don't go to deep sleep will win handily.
Bluetooth mice also gave wireless mice a bad name, and so a lot of gaming mice still have tails. The proprietary wireless interfaces are much less power hungry and respond so fast I can't tell the difference between my current midrange wireless mouse and the midrange corded one it replaced, other than no longer having the wire get tangled at inopportune moments.
Any time you have a 975-member team to do your taxes - I don't care how big a company you have - something is broken. That's an immense waste, mirrored by similar wastes on the IRS's side.
That waste runs all the way down to the smallest scale. I shouldn't need to hire a professional to handle my individual tax return.
This is why we need municipal fiber. Not service on the fiber - just the physical glass.
The model is simple: the city rents you a pair of strands for a nominal charge per month (about $10). That gets you into a central data center, where it may be cross-connected to your choice of service providers. For example, in Palo Alto, that means PAIX, where there are about 150 ISPs competing for your business, and similar situations exist in several other cities. Try a cheap one! Crappy service? Switch to a classier provider! Want one that runs ATM to get latency guarantees for traditional telephony? Switch to one that does it! Decided you'd rather pay by the bit than by the month? You can! Switching is easy: you sign up with the new place, and when they're ready for you, you or the ISP issue a change request to the data center. They unplug your patch from the old ISP and into the new one, and away you go.
Everyone wins except for the incumbent telcos who are raping you for services because they control the natural monopoly: the physical line.
You present a false dichotomy. It's not a black and white issue. I didn't say it was safe. I said it was less than Chernobyl. I wouldn't want to live next door to the plant, but I would not have any qualms about living a quarter of the Chernobyl exclusion zone's radius from Daiichi. Closer in you'll see temporary evacuations and I wouldn't want to deal with that, but long-term I'd have no problem moving there. Also, the situation has the potential to get worse, though I think we hit bottom some days ago and it's only going to get better from here.
Ummm no, what this shows is that they used sea water to cool the reactors instead of de-mineralised water.
How do you form large quantities of I-131 and Cs-137 by cooling a shut down reactor with seawater? The heaviest nuclei you get in appreciable amounts (>.001%) in seawater are Br-81 and Sr-88.
As to the corium issue, there has been no indication what so ever that the core temp has risen above 1000C (and hence no corium).
The first indication is the I-131 and Cs-137. These are formed by the fission of uranium. Normally they're contained within the zircalloy fuel cladding. The cladding starts to fail about 850C. Some of it bursts releasing the above radionuclides. Around 1250C it rapidly oxidizes, generating hydrogen. Remember those hydrogen explosions? That's your second indication.
You're partly right - these isotopes are the most hazardous. However, radiation is really only dangerous in high concentrations. These radionuclides disperse easily down to irrelevant levels. The real problem is when you have large amounts of radioactive soot coming down in high concentrations in a specific area. That's what made such a mess in the USSR.
They're a lower thermal load than the recently shut down reactors, and since they're outside of containment, it's an easier job to monitor and fill them. I had a low confidence that this was being done adequately until they started taking IR temperature measurements which have been showing the pools are considerably below boiling. As long as they can keep enough water in them, they should be fine.
Since it appears none of the reactors have actually melted down or suffered a substantial failure in containment in the immediate vicinity of the rods themselves, it's quite likely that they'll be able to take them through a more or less normal shutdown and decommissioning once proper cooling is restored...
Actually, the high I-131 and Cs-137 levels pretty well indicate that at least a partial meltdown has occurred. We'll only know for sure once we're able to crack them open and see what's inside, but my money's on it looking a lot like the TMI leftovers. With a mess of corium casserole inside, they're not going to just pop the lid off and pull the fuel bundles like any other shutdown. It'll be years before they peek inside, and years more before they've finished scraping the slag out. That's much better than Chernobyl where angry flaming core got spooed everywhere, but it's hardly a "normal" decommissioning.
A becquerel is a specific quantity of I-131. It can be converted to grams. It will be a much smaller mass than a becquerel of I-129, which has a much longer half-life. When they say "N becquerels per day", think "N * (conversion factor) grams per day".
Another way to think about it is this: The amount released each day will result in 1.3E17 decays per second occurring in the wild. After two days, you will have 2.6E17 decays per second scattered through the world. (It will actually be slightly less than this since some of it already decayed, but I think you get the idea.)
More generally, (Quantity) / ( (Time) * (Time ) ) == Quantity / (Time ** 2) == Acceleration. For instance, 1 mile per hour per second actually makes sense: It means each second you're going 1 MPH faster.
The problem is the title: "Fukushima radioactive fallout nears Chernobyl levels"
The headline is actually worse than sensationalist: It's an outright lie. Fallout of Cs-137 and I-131 are at near Chernobyl levels, but the fallout, as a whole, is far far less than Chernobyl.
I actually don't have a problem with that. RedHat does not have an exclusive right as a distributor. My personal belief is that if the world gets better use of the software by distributing it more in this manner, that net good is being done.
The GPL ethos is you sell support, not software. The playing field is supposed to be level for the software, and you make a name by being the best at support. What RH is doing here is pushing for the software itself to be the feature they're selling, and that's going to rub a lot of people the wrong way - it wasn't the deal intended when they GPLed their code.
TFA doesn't specify what this actually means, so let me speculate. They're not going to go closed-source; they'd be lynched. I think this is a reference to the fact that they're distributing their source prepatched now, to make it harder to just take their patches and apply them to other distros.
IMO that's kind of sleazy. They got where they are standing on the shoulders of giants. The deal was: here, have this free stuff, build on it, make money with it, but you have to keep giving back. And they got their value out of it, but now they're trying to give back only the minimum they're contractually obligated to do. It's legal and not purely evil, but still moderately scummy.
I don't really see it being that good for them, either. Oracle isn't going to have much trouble reverse-engineering the patches back out, but RedHat now ends up in a more difficult position: fewer of their patches will be incorporated upstream, so they have to spend more work porting them into each new release; they'll have less community review and bugfixes in their patches; and they're going to alienate the community.
On the other hand RH users won't end up in the worst scenario: stuck using RH's buggy crap and unable to do anything about it. The source will still be there; they can still dive in to figure out what's wrong and fix it instead of dealing with a black box. I know I had to more than a few times when supporting RHEL systems.
This is common objection to flight envelope protection systems. People's gut reaction is that in an emergency, they'd rather be in total control than have some computer "interfering" with them. But the statistics are on the other side: Pilot error is more common than computer error.
China Airlines Flight 006 is a prime example. They had a mechanical failure, and while the flight crew was distracted, the plane ended up in an ugly dive. They pulled it out after exceeding 5 Gs, badly damaging the airframe, and losing a considerable amount of altitude. Manual-control advocates say this is a good example of why you don't want a computer imposing limits on you - they had to do drastic things to save the plane. I disagree - if they were flying an Airbus, the computer would have prevented the situation from ever occurring.
The second argument in favor of flight envelope protection is that it actually enables the pilot to push the plane harder in an emergency. Consider this scenario: you're landing in low visibility, still a good ways out. Everything looks fine, but as you break out of the clouds, holy crap there's a skyscraper. You have a split second to evade it. With mechanical controls, you have to roll hard, but not *too* hard, or you'll ( break the plane | spin | exceed max angle of attack | etc). In a modern Airbus, you slam the stick over, and the plane will roll as fast as it can within its mechanical limits. Perhaps that's not as fast as an experienced military pilot could in a familiar plane which they regularly take to its limits, but a commercial pilot probably hasn't been over 2 Gs in a while, and in that split-second emergency, the computer will let them fly it harder than they ever could on their own.
So it's time for a car analogy. I have two cars I drive regularly: one has antilock brakes; the other does not. The mechanical limits are similar: light cars, good sticky tires, brake pads with plenty of bite, etc. On a good day, my stopping distance is similar between them, +/- a meter. But I've been put in emergency deer-avoidance situations with both cars on multiple occasions. In the ABS car, that means stomp on the brakes, burn off as much speed as possible in a straight line, and swerve at the last minute once the deer's finally decided which way to dart. In the non-ABS car, I'm pretty good at braking on the track, but both times it's been for a deer, my response was the same: ease into it, feeling where the limit is; crap locked up a wheel, let go for a moment and ease back into it to try to get just shy of the limit again; and occasionally letting off to steer early, because my ability to manage my grip budget is too taxed to get it perfectly right at the last minute. I haven't hit a deer yet - but that's only because I drive the non-ABS car slower.
The difference is very noticeable: when taken by surprise, the computer can stop faster than I can, AND it lets me focus on the situation instead of the limits of the machine. I believe the same is true for flight control systems, and statistics agree: they prevent more accidents due to pilot error than they cause due to computer malfunction. Note that there's not much difference between Airbus and Boeing these days, but Airbus pulled ahead in safety until Boeing started equipping their planes with flight envelope protection systems. Both brands are considerably safer than they were in the full-manual days.
I've done a fair bit of CAD work, and am pretty fluent in AutoCAD. I tried to use qcad for some simple things, but it's *really* lacking in basic functionality. Things like: Create a block. Assign layers to elements of a block. Set certain line colors to specific values, some to bylayer. Give the layer a color. Insert the block into a drawing. Change its color. The elements on a layer within the block inherit the attributes from the BLOCK's layer.
It's so wrong on such a simple bit of functionality that I couldn't take it seriously for anything more than arranging the furniture in my room, and even for that I felt like its limits were sometimes exceeded.
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I don't weld that much but yes, I have discovered the joy of cheater helmets. I miss a lot less now. :)
For an example of how this works, go into a mostly dark room with a camera. Have a look around. Turn on the camera, look straight into the flash as you fire it. Have a look around again.... Your wide-open pupils just let the full force of the flash in before you could blink, every receptor on your retina just fired, and it's going to be a few minutes before you can see anything again.
With a high enough power light source, this works just fine in daylight. I know this because I've flashed myself with a MIG welder - It was just a brief flash as I flicked the trigger at an inopportune moment, but the center of my vision was completely blank for several minutes. Simply turning off the machine and finding a safe place to sit down to wait for my vision to return was a challenge. I would have been screwed in a melee.
Anyway, no, goggles won't save you. If it's white light, you can't filter a narrow band like laser goggles. When welding with a shade 10 filter, when the arc is on, you can see what you're working on OK, but the arc itself is just white, completely clipping at the top of your eyes' sensitivity. When you turn the arc off, you're blind if you're indoors unless you have a 150 watt light inches away from what you're looking at. Outdoors you can just barely see what's going on, but at many angles the reflections of light leaking in from behind you overwhelm your forward vision (like with glossy screen laptops used outdoors, but worse). Using those kind of lenses will leave you blind anyway - they wouldn't need to flash you. Anything less and you'll still be vulnerable to the flash.
I think it's because of the hubris of calling it "awesome". Some people were bound to not like it, but being told it's awesome when you don't like it makes them feel like it's being forced on them by completely out of touch developers.
More specifically, people make very poor safety judgments on very rare, high-consequences events. For instance:
* Computerized flight envelope protection systems increase safety overall, but pilots balk at the idea that the computer is taking away some of their control
* Nuclear reactors have the best safety record of any large scale power generation technology, but people are terrified of them
* Pretty much anything the TSA does
And there are idiotic memes that just won't go away:
* People's belief that cell phones and WiFi will give them cancer, which holds up infrastructure deployments :)
* People disabling airbags and not using seat belts because they have a friend of a friend who got away unscathed without them
* Religion.
I'm a satisfied Crashplan user. I subscribe to the Crashplan Central service (They're calling it Crashplan+ Family Unlimited now), which means I get unlimited (Which appears to be *actually* unlimited, not Comcast-unlimited) backups to their disk farm in a bank vault in Minnesota. I get to back up all my computers - laptops, desktops, and even my personal VPS - all automatically, with staged version retention, and no hassles of running out of disk or other typical backups shenanigans. Totally does what it says.
I picked it because it: has unlimited seats so I can back up all my computers; it works on Linux, OSX, and Windows; and it has several security models, including "manually generate and install encryption keys on a per-machine basis, and make damn sure you back them up somewhere safe because we only have your encrypted data", which I use because it's compatible with my tinfoil hat.
One complaint: On my VPS, it creates some sort of cache that gradually grows to gigs in size. I suspect it's due to indexing the very large number of files that maildirs create. If it runs out of disk, the process starts consuming 100% CPU. Lame. So I have a cron job that shuts it down, blows away the cache, and restarts it periodically.
On the whole: Completely worth 600 pennies a month.
Review 2: My previous solution was BackupPC. I arrived at it after using similar but less refined backups like rsnapshot and dirvish. BackupPC was the best - you just have to throw lots of disk at it, and it does what it promises. If you can do cross-site backups, it's pretty damn good. The downsides were that you have to plan ahead to have enough disk, and the disk IO during backups was unexpectedly high.
I still occasionally make a manual copy of everything and leave it in a safe deposit box. Defense in Depth is a good thing.
Mods are where it's at. Boxed releases are meant to be easy for a broad audience, most of who can't handle teamwork.
PR is *brutal* on people who can't work as a team. Occasionally you get some dork who won't follow orders and just Rambos around. He quickly ends up without a squad. Soloing in PR sucks - long stretches of hiking with no action, then a well organized squad takes you out. They get frustrated with that routine pretty quickly and uninstall the mod, having decided it's lame. The ones that remain are fair to good.
I used to be in Bellum Aeternus on PlanetSide. We played the Vanu team (generally considered to be "hard mode" for PlanetSide, at least back then). The clan was great - coordinated assaults and organized defense can take out utter hordes of Terran / NC zerglings. Over the course of the day we'd completely take over most of the universe, triumphing even when the other two races would team up against us. I heard it fell apart eventually, though.
Long ago, it was lmctf (Loki's Minions CTF mod) for Quake 2. That was the most fun I've ever had. Again, lots of people who know the basics: Coordinated, communicating base defense organized at choke points; designated flag carriers and escorts carrying appropriate runes; people who understand and use sophisticated tactics. "ROAR! ... This... is CNN." ... You had to be there. :)
If it's a corded mouse, it may never goes to really deep sleep. Cordless mice are the ones that have very aggressive sleep patterns.
I agree that it'll be overblown, BUT...
If the correlation is real, and it holds up under review (don't count on it), it'll certainly get my attention even if the effect is minuscule.
That depends on the game. If you're playing Quake-style deathmatch, sure, that kind of camping is lame.
I play things like Project Reality where the maps are enormous and the gameplay is much slower. You squad up and hike across the map for a good several minutes without any enemy contact (though you have to be constantly on your toes). You reach a river. The whole squad crossing at once is suicidal, so you go in pairs, with everyone else staying in the trees and ready to provide cover fire. With 30 seconds for each pair to cross the river, you're going to be sitting there watching your sector for a while. Constantly looking around to keep your mouse awake just makes you easier to see. When you see a muzzle flash on the far bank, you have to react fast: the shooter's already cycling in the next round, and he's sure to have friends. The 1 second it takes your mouse to wake up is an eternity when the guy crouching next to you just took one in the head.
If you live through that exercise and make it to the enemy base, the first part is easy: run in, blow away anyone who objects to your presence. But then you have to hold the territory until you achieve the capture, which means a couple minutes of hiding on the porch or behind some sandbags, holding your breath. It's not going to be a surprise attack: you know the reinforcements are coming; it's just a matter of when and where. Moving means you become the canary. Lag - including from your mouse - means you will let your squad down when half a dozen bad guys with assault rifles jump out of the alley.
A good gaming mouse should have:
* An ergonomic shape to hold for a couple hours at a time. I find that it works well to have a more arched shape for continuous use, instead of a flatter shape for reaching over to occasionally click something. Thumb rests are also popular.
* Lots of buttons, in a convenient arrangement.
* High resolution. Even if you don't want it to track fast, you want the tracking quantum to be small. For productivity apps, on the other hand, a larger quantum is nice to prevent it from accidentally moving.
There are also firmware differences. Ever notice how the LED goes dim when you're idling? That's a power saving strategy. It's actually just flashing it on occasionally to see if it's moved, then going back to sleep. Cordless productivity mice do this very aggressively, and you *will* miss that golden headshot opportunity if your mouse is idled down, since it won't start tracking again until the next flash - which can be as infrequent as once every couple seconds if you've been camping a while and it's gone into deep sleep.
TFA is measuring performance of speed clicking a bunch of icons. The mouse will never go to sleep in this scenario. If they tried another benchmark - like, hold still for 30 seconds and then click the icon as fast as you can - you will see some BIG differences, and gaming mice that don't go to deep sleep will win handily.
Bluetooth mice also gave wireless mice a bad name, and so a lot of gaming mice still have tails. The proprietary wireless interfaces are much less power hungry and respond so fast I can't tell the difference between my current midrange wireless mouse and the midrange corded one it replaced, other than no longer having the wire get tangled at inopportune moments.
Any time you have a 975-member team to do your taxes - I don't care how big a company you have - something is broken. That's an immense waste, mirrored by similar wastes on the IRS's side.
That waste runs all the way down to the smallest scale. I shouldn't need to hire a professional to handle my individual tax return.
This is why we need municipal fiber. Not service on the fiber - just the physical glass.
The model is simple: the city rents you a pair of strands for a nominal charge per month (about $10). That gets you into a central data center, where it may be cross-connected to your choice of service providers. For example, in Palo Alto, that means PAIX, where there are about 150 ISPs competing for your business, and similar situations exist in several other cities. Try a cheap one! Crappy service? Switch to a classier provider! Want one that runs ATM to get latency guarantees for traditional telephony? Switch to one that does it! Decided you'd rather pay by the bit than by the month? You can! Switching is easy: you sign up with the new place, and when they're ready for you, you or the ISP issue a change request to the data center. They unplug your patch from the old ISP and into the new one, and away you go.
Everyone wins except for the incumbent telcos who are raping you for services because they control the natural monopoly: the physical line.
[Steps back off soapbox]
You present a false dichotomy. It's not a black and white issue. I didn't say it was safe. I said it was less than Chernobyl. I wouldn't want to live next door to the plant, but I would not have any qualms about living a quarter of the Chernobyl exclusion zone's radius from Daiichi. Closer in you'll see temporary evacuations and I wouldn't want to deal with that, but long-term I'd have no problem moving there. Also, the situation has the potential to get worse, though I think we hit bottom some days ago and it's only going to get better from here.
Ummm no, what this shows is that they used sea water to cool the reactors instead of de-mineralised water.
How do you form large quantities of I-131 and Cs-137 by cooling a shut down reactor with seawater? The heaviest nuclei you get in appreciable amounts (> .001%) in seawater are Br-81 and Sr-88.
As to the corium issue, there has been no indication what so ever that the core temp has risen above 1000C (and hence no corium).
The first indication is the I-131 and Cs-137. These are formed by the fission of uranium. Normally they're contained within the zircalloy fuel cladding. The cladding starts to fail about 850C. Some of it bursts releasing the above radionuclides. Around 1250C it rapidly oxidizes, generating hydrogen. Remember those hydrogen explosions? That's your second indication.
You're partly right - these isotopes are the most hazardous. However, radiation is really only dangerous in high concentrations. These radionuclides disperse easily down to irrelevant levels. The real problem is when you have large amounts of radioactive soot coming down in high concentrations in a specific area. That's what made such a mess in the USSR.
They're a lower thermal load than the recently shut down reactors, and since they're outside of containment, it's an easier job to monitor and fill them. I had a low confidence that this was being done adequately until they started taking IR temperature measurements which have been showing the pools are considerably below boiling. As long as they can keep enough water in them, they should be fine.
Since it appears none of the reactors have actually melted down or suffered a substantial failure in containment in the immediate vicinity of the rods themselves, it's quite likely that they'll be able to take them through a more or less normal shutdown and decommissioning once proper cooling is restored ...
Actually, the high I-131 and Cs-137 levels pretty well indicate that at least a partial meltdown has occurred. We'll only know for sure once we're able to crack them open and see what's inside, but my money's on it looking a lot like the TMI leftovers. With a mess of corium casserole inside, they're not going to just pop the lid off and pull the fuel bundles like any other shutdown. It'll be years before they peek inside, and years more before they've finished scraping the slag out. That's much better than Chernobyl where angry flaming core got spooed everywhere, but it's hardly a "normal" decommissioning.
A becquerel is a specific quantity of I-131. It can be converted to grams. It will be a much smaller mass than a becquerel of I-129, which has a much longer half-life. When they say "N becquerels per day", think "N * (conversion factor) grams per day".
Another way to think about it is this: The amount released each day will result in 1.3E17 decays per second occurring in the wild. After two days, you will have 2.6E17 decays per second scattered through the world. (It will actually be slightly less than this since some of it already decayed, but I think you get the idea.)
More generally, (Quantity) / ( (Time) * (Time ) ) == Quantity / (Time ** 2) == Acceleration. For instance, 1 mile per hour per second actually makes sense: It means each second you're going 1 MPH faster.
Hopefully one of these explanations will help. :)
The problem is the title: "Fukushima radioactive fallout nears Chernobyl levels"
The headline is actually worse than sensationalist: It's an outright lie. Fallout of Cs-137 and I-131 are at near Chernobyl levels, but the fallout, as a whole, is far far less than Chernobyl.
RHEL customers don't need the individual patches. They just download and install the updated RPMs from RedHat.
Or do I misunderstand what you're saying?
I actually don't have a problem with that. RedHat does not have an exclusive right as a distributor. My personal belief is that if the world gets better use of the software by distributing it more in this manner, that net good is being done.
The GPL ethos is you sell support, not software. The playing field is supposed to be level for the software, and you make a name by being the best at support. What RH is doing here is pushing for the software itself to be the feature they're selling, and that's going to rub a lot of people the wrong way - it wasn't the deal intended when they GPLed their code.
That's a good point. And a lot of their work is in backporting new features into old kernels, to which my criticism is less valid.
TFA doesn't specify what this actually means, so let me speculate. They're not going to go closed-source; they'd be lynched. I think this is a reference to the fact that they're distributing their source prepatched now, to make it harder to just take their patches and apply them to other distros.
IMO that's kind of sleazy. They got where they are standing on the shoulders of giants. The deal was: here, have this free stuff, build on it, make money with it, but you have to keep giving back. And they got their value out of it, but now they're trying to give back only the minimum they're contractually obligated to do. It's legal and not purely evil, but still moderately scummy.
I don't really see it being that good for them, either. Oracle isn't going to have much trouble reverse-engineering the patches back out, but RedHat now ends up in a more difficult position: fewer of their patches will be incorporated upstream, so they have to spend more work porting them into each new release; they'll have less community review and bugfixes in their patches; and they're going to alienate the community.
On the other hand RH users won't end up in the worst scenario: stuck using RH's buggy crap and unable to do anything about it. The source will still be there; they can still dive in to figure out what's wrong and fix it instead of dealing with a black box. I know I had to more than a few times when supporting RHEL systems.
This is common objection to flight envelope protection systems. People's gut reaction is that in an emergency, they'd rather be in total control than have some computer "interfering" with them. But the statistics are on the other side: Pilot error is more common than computer error.
China Airlines Flight 006 is a prime example. They had a mechanical failure, and while the flight crew was distracted, the plane ended up in an ugly dive. They pulled it out after exceeding 5 Gs, badly damaging the airframe, and losing a considerable amount of altitude. Manual-control advocates say this is a good example of why you don't want a computer imposing limits on you - they had to do drastic things to save the plane. I disagree - if they were flying an Airbus, the computer would have prevented the situation from ever occurring.
The second argument in favor of flight envelope protection is that it actually enables the pilot to push the plane harder in an emergency. Consider this scenario: you're landing in low visibility, still a good ways out. Everything looks fine, but as you break out of the clouds, holy crap there's a skyscraper. You have a split second to evade it. With mechanical controls, you have to roll hard, but not *too* hard, or you'll ( break the plane | spin | exceed max angle of attack | etc). In a modern Airbus, you slam the stick over, and the plane will roll as fast as it can within its mechanical limits. Perhaps that's not as fast as an experienced military pilot could in a familiar plane which they regularly take to its limits, but a commercial pilot probably hasn't been over 2 Gs in a while, and in that split-second emergency, the computer will let them fly it harder than they ever could on their own.
So it's time for a car analogy. I have two cars I drive regularly: one has antilock brakes; the other does not. The mechanical limits are similar: light cars, good sticky tires, brake pads with plenty of bite, etc. On a good day, my stopping distance is similar between them, +/- a meter. But I've been put in emergency deer-avoidance situations with both cars on multiple occasions. In the ABS car, that means stomp on the brakes, burn off as much speed as possible in a straight line, and swerve at the last minute once the deer's finally decided which way to dart. In the non-ABS car, I'm pretty good at braking on the track, but both times it's been for a deer, my response was the same: ease into it, feeling where the limit is; crap locked up a wheel, let go for a moment and ease back into it to try to get just shy of the limit again; and occasionally letting off to steer early, because my ability to manage my grip budget is too taxed to get it perfectly right at the last minute. I haven't hit a deer yet - but that's only because I drive the non-ABS car slower.
The difference is very noticeable: when taken by surprise, the computer can stop faster than I can, AND it lets me focus on the situation instead of the limits of the machine. I believe the same is true for flight control systems, and statistics agree: they prevent more accidents due to pilot error than they cause due to computer malfunction. Note that there's not much difference between Airbus and Boeing these days, but Airbus pulled ahead in safety until Boeing started equipping their planes with flight envelope protection systems. Both brands are considerably safer than they were in the full-manual days.
qcad is *very* low-end.
I've done a fair bit of CAD work, and am pretty fluent in AutoCAD. I tried to use qcad for some simple things, but it's *really* lacking in basic functionality. Things like: Create a block. Assign layers to elements of a block. Set certain line colors to specific values, some to bylayer. Give the layer a color. Insert the block into a drawing. Change its color. The elements on a layer within the block inherit the attributes from the BLOCK's layer.
It's so wrong on such a simple bit of functionality that I couldn't take it seriously for anything more than arranging the furniture in my room, and even for that I felt like its limits were sometimes exceeded.
We really need more 2D CAD options in Linux.