I'm working in the field, and have never heard this distinction. You're right about collider, but anything which accelerates particles (including particles which are destined to be collided with another beam) can be called a particle accelerator.
This is pretty much what the LHC does. If you look at the dipole magnet cross section [1], you see there are two beam pipes, with oposite magnetic field. Thus we actually have two rings in (mostly) one set of magnets, with counter-rotating beams. These beams are then focused and brought into collision at the four interaction points ATLAS, CMS, LHCb, and ALICE.
If one uses particles of opposite charge, such as matter and antimatter (which was done for LEP, Sp\bar pS and TEVATRON), one can use the same magnets and beam pipes for bending in the ring, but you still need separate sets of magnets for focusing etc., and probably also separate set of RF cavities for acceleration.
Oh, and when you mention electronic brakes: The guy/girl who came out with the idea of the electronic parking brake should be heavily reprimanded, especially for the choice of user interface: A 4th pedal or "drawer", neither which permit quick and precise control of braking force, gives no feedback, and for the 4th pedal, using your HAND on the HANDBRAKE while both your feet are occupied with the clutch and throtle (very usefull when starting in a steep hill with a heavy load or a weak engine).
Gah. I admit to freaking out the first time I got into a car and realized there where 4 pedals and not the 3 I'm used to seeing. I hope they place it far to the left, away from where the clutch is normally sitting, when they build it into a car with automatic transmission. If not, I can totally see myself pushing the parking brake while expecting it to be the clutch, with unexpected effects.
Yeah, I noticed there where no "mechanical feel" to some automatic rentals I've had in the US (living in Europe, where 95% are manuals). It always feels very strange / "video-game-like" to use the manual gear selector on a automatic (for steep downhills / dirt roads / etc. - cases where I'm not going very fast but really want the control myself.).
Does really steer-by-wire steering excist for cars? Also, in ABS brakes, how does it actually interupt braking power - as the breaks DO work (sans amplifier) when power is switched off and there is a hydraulic line from the pedal to the brakes? As for electronic throtles, the ones I've heard of before have some kind of failure detection (usually using redundant & voting systems), and if an error is detected, it sets the throtle angle to "fast idle" (often by a spring loading), i.e. a limp-home-mode where you control the speed by the gear changer. Unless there is a really bad error of course, like in this article...
By the way, there are one completely mechanical mode where you'll get unintended (and very-hard-to-control) acceleration: A diesel engine is controlled not by air flow but by fuel flow. Thus if there is a large leak of engine oil into the cylinders, or the air contains fuel (gas leak etc.), it may rev uncontrollably, and the only way (I know) to stop it is to put so much load on it that its killed, i.e. braking and abruptly dropping it into the highest gear at slow speed. I would think petrol engines may have a similar failure mode if there is a large air leak past the throtle?
And anyway, damaged or broken engine >> (>>>>>) uncontrolled acceleration. People just need to learn to prioritize - a thing you may replace, your life not so much. OTOH, some people behave like idiots, and hopefully they just take themselves out of the gene pool...
Still happy that my car (not a Toyota) has a stick and thus a mechanical clutch pedal:)
On the other hand, doesn't automatic gearboxes have neutral setting? Wouldn't moving into this be roughly the same as depressing the clutch on a manual gearbox? Of course, the reaction times are longer (since you have to do something unusual when driving an automatic, i.e. touching the shifter while in motion), but for the cases you hear of where they managed to call 911 while figthing to control the vehicle...
It's not always cold: http://www.yr.no/place/Norway/Oslo/Oslo/Oslo/statistics.html Sorry if it's in C not F, but in general: 0C is the freezing temp of water, 20 is comfortable, 30 is really hot, -5 is normal cold, -10 is quite cold, and -20 is freeze-your-balls-off-cold. Luckilly, that doesn't happen to often.
Generally the winter weather in the city (which is by the sea, or at least a small fjord) is quite variable. The proximity to water also means that it *may* be humid - and humidity amplifies the feeling of coldness. -20 and dry is really prefferable to -1 when its snowing wet snow (melting on the ground, freezing overnight... Makes it interesting to live in the university student village where most of the exchange students also live...), especially if there is any wind chill...
So yeah, we also do get sticky snow, especially at the ends of the seasons. The frequent temperature cycles also makes for tons of ice. Still, this isn't a problem for trafic lights - I guess it's down to the design. All trafic light lamps have a "baseball cap" sticking out over them, which is rounded and smooth on the top, meaning that wet snow just slips off. Also, there is no need for collimator "blinds" to make it visible in strong sunlight. An finally, there has been a trend for the last ~30 years or so (as in most of Europe) to build roundabouts wherever there is space for one.
Sounds like they're doing something wrong. Most of the trafic lights in Oslo* where switched to LED the last 10 years, and I can't remember that ever happening...
* Where it does sometimes get... hmm.. cold. And sometimes we get a few meters of snow too, which stays untill... spring. No polar bears walking around in the streets tough, that's Longyearbyen at Svalbard (island faaaaaaaaar north):)
Unfortunately, so does LED. They tested a similar rollout in Oslo recently, but had to stop when they discovered that the LEDs aged far more rapidly than the old sodium fixtures.
In this case its not patented, but if it where, just declaring the patents invalid would be a bad idea. If they did that, european nations may also look at which patents are annoying AND held by US companies, and declare some of them invalid as well.
Basically, this isn't worth risking a trade war over, and it isn't worth starting up a production line because of it. Alternatives exsist. The EU also knows that it isn't worth the risk for the US - that's why they do it.
But is Iran using these drugs for executions? Because that's what the threathened export ban to the US is about. I doubt we're selling high-speed centrifuges (for isotope separation / nuclear weapons programs) etc. to Iran either.
Yeah. I've visited SF a few times (living in Europe), and the transit there is a sad joke. BART must be the worlds slowest subway system, CalTrain is a diesel train crossing everywhere at street level (making HOOOOT HOOOOT HOOOOOOOOOOT noises as it does), the highways are generally clogged, and inside SF its even worse. Only good thing is that CalTrain alows you to bring your bike - most sensible method of transportation inside SF, and the Marguerite shuttle network around Stanford/SLAC, which also allows you to bring a bike - excelent when you're working at SLAC on the top of the hill, while living in Menlo at the bottom of it, and the SLAC shuttle stops running before I normally leave work...
This isn't a (huge) problem in most other subway systems I've used. Never been to NY tough, so maybe people are completely different there - but I would suspect not.
Having frequent departures also helps this - missing a train isn't a big deal if there is another one comming in ~5 minutes or so, worse if you have to wait 15 or more.
I would be surprised if everything - especially valve springs and other timing-critical parts - are just scaled dimensionally.
A better example than a engine is a pendulum, which period is 2*pi*sqrt(L/g). If you change L, the frequency changes. If this pendulum (or similar part) is part of a machine, and there are multiple such parts, which doesn't neccessarily scale the same way, you end up with parts which was syncronized at one scale, not being synchronized at another scale. For an interference engine, that would mean something like the valve not closing properly before the cylinder comes -> clash & extensive damage.
I've been thinking the same about US universities - they all seem to have some kind of "campus police" - is that really needed, can't you just call the normal police when needed, plus maybe have a few normal security people to switch off the lights, lock the doors, and let people who's forgotten their keys/access card in/out?
But wounded horses, especially those that where unlucky to break a leg (not easy to heal properly), end up on the table. And yes, horse meat often taste very good - more taste than beef, usually tender, and much cheaper.
At least here in France there is a nice section with horse in the supermarket next to beef etc. - I think it is actually bigger than sheep meat (opposite of my native Norway, where most supermarkets carry horse (and good ones, whale), but sheep is at least as common as cow).
BTW, this is one reason why I take all the global warming predictions with a big grain of salt - they are all based on computer simulations which are difficult if not impossible to validate, and given what I've seen, I don't trust the results from them at all.
In the case of climate simulations, different models (both physics-wise and code-wise) are run with different computers on the same input data, and yield basically the same results.
When simulation chaotic behaviour, very small differences can make a big difference in the outcome of your simulations. As an example, I'm currently working on simulations of sparks in vacuum, which is a "runaway" process. In this case, adding a single particle early in the simulations (before the spark actually happens) can change the time for the spark to appear by several tens of %. This also happens if we are running with different library versions (SuperLU, Lapack), different compilers, and different compiler flags. Once the spark happens, the behaviour is predictable and repeatable - but the time for it to happen, as the system is "balancing on the edge, before falling over", is quite random.
Slashdot Mirror
Shame that these tunnels gets too radioactive that I would want to live in one...
No, not really - I would rather estimate it as roughly half the cost.
The big problem with the SSC is that it was a complete green field project, unlike to CERN which started small and then built up.
I'm working in the field, and have never heard this distinction. You're right about collider, but anything which accelerates particles (including particles which are destined to be collided with another beam) can be called a particle accelerator.
This is pretty much what the LHC does. If you look at the dipole magnet cross section [1], you see there are two beam pipes, with oposite magnetic field. Thus we actually have two rings in (mostly) one set of magnets, with counter-rotating beams. These beams are then focused and brought into collision at the four interaction points ATLAS, CMS, LHCb, and ALICE.
If one uses particles of opposite charge, such as matter and antimatter (which was done for LEP, Sp\bar pS and TEVATRON), one can use the same magnets and beam pipes for bending in the ring, but you still need separate sets of magnets for focusing etc., and probably also separate set of RF cavities for acceleration.
[1] http://lhc-machine-outreach.web.cern.ch/lhc-machine-outreach/components/magnets.htm
Thorium is pretty abundant, so its probably not worth figthing over. Most countries have access to enough of the stuff.
Yeah, I've heard the test is pretty easy in the US. We (Norway) have a lot of obligatory training, so for most people the license costs ~2-4000* $.
*) Basic salaries and cost of living is higher than in the US as well, but still, f*ing expensive when you're 18.
Oh, and when you mention electronic brakes: The guy/girl who came out with the idea of the electronic parking brake should be heavily reprimanded, especially for the choice of user interface: A 4th pedal or "drawer", neither which permit quick and precise control of braking force, gives no feedback, and for the 4th pedal, using your HAND on the HANDBRAKE while both your feet are occupied with the clutch and throtle (very usefull when starting in a steep hill with a heavy load or a weak engine).
Gah. I admit to freaking out the first time I got into a car and realized there where 4 pedals and not the 3 I'm used to seeing. I hope they place it far to the left, away from where the clutch is normally sitting, when they build it into a car with automatic transmission. If not, I can totally see myself pushing the parking brake while expecting it to be the clutch, with unexpected effects.
Yeah, I noticed there where no "mechanical feel" to some automatic rentals I've had in the US (living in Europe, where 95% are manuals). It always feels very strange / "video-game-like" to use the manual gear selector on a automatic (for steep downhills / dirt roads / etc. - cases where I'm not going very fast but really want the control myself.).
Does really steer-by-wire steering excist for cars? Also, in ABS brakes, how does it actually interupt braking power - as the breaks DO work (sans amplifier) when power is switched off and there is a hydraulic line from the pedal to the brakes? As for electronic throtles, the ones I've heard of before have some kind of failure detection (usually using redundant & voting systems), and if an error is detected, it sets the throtle angle to "fast idle" (often by a spring loading), i.e. a limp-home-mode where you control the speed by the gear changer. Unless there is a really bad error of course, like in this article...
By the way, there are one completely mechanical mode where you'll get unintended (and very-hard-to-control) acceleration: A diesel engine is controlled not by air flow but by fuel flow. Thus if there is a large leak of engine oil into the cylinders, or the air contains fuel (gas leak etc.), it may rev uncontrollably, and the only way (I know) to stop it is to put so much load on it that its killed, i.e. braking and abruptly dropping it into the highest gear at slow speed. I would think petrol engines may have a similar failure mode if there is a large air leak past the throtle?
And anyway, damaged or broken engine >> (>>>>>) uncontrolled acceleration. People just need to learn to prioritize - a thing you may replace, your life not so much. OTOH, some people behave like idiots, and hopefully they just take themselves out of the gene pool...
Still happy that my car (not a Toyota) has a stick and thus a mechanical clutch pedal :)
On the other hand, doesn't automatic gearboxes have neutral setting? Wouldn't moving into this be roughly the same as depressing the clutch on a manual gearbox? Of course, the reaction times are longer (since you have to do something unusual when driving an automatic, i.e. touching the shifter while in motion), but for the cases you hear of where they managed to call 911 while figthing to control the vehicle...
It's not always cold:
http://www.yr.no/place/Norway/Oslo/Oslo/Oslo/statistics.html
Sorry if it's in C not F, but in general: 0C is the freezing temp of water, 20 is comfortable, 30 is really hot, -5 is normal cold, -10 is quite cold, and -20 is freeze-your-balls-off-cold. Luckilly, that doesn't happen to often.
Generally the winter weather in the city (which is by the sea, or at least a small fjord) is quite variable. The proximity to water also means that it *may* be humid - and humidity amplifies the feeling of coldness. -20 and dry is really prefferable to -1 when its snowing wet snow (melting on the ground, freezing overnight... Makes it interesting to live in the university student village where most of the exchange students also live...), especially if there is any wind chill...
So yeah, we also do get sticky snow, especially at the ends of the seasons. The frequent temperature cycles also makes for tons of ice. Still, this isn't a problem for trafic lights - I guess it's down to the design. All trafic light lamps have a "baseball cap" sticking out over them, which is rounded and smooth on the top, meaning that wet snow just slips off. Also, there is no need for collimator "blinds" to make it visible in strong sunlight. An finally, there has been a trend for the last ~30 years or so (as in most of Europe) to build roundabouts wherever there is space for one.
They might also have to move the poles around / add more poles. So it migth not be possible to do it on a pole-by-pole basis.
Sounds like they're doing something wrong. Most of the trafic lights in Oslo* where switched to LED the last 10 years, and I can't remember that ever happening...
* Where it does sometimes get... hmm.. cold. And sometimes we get a few meters of snow too, which stays untill... spring. No polar bears walking around in the streets tough, that's Longyearbyen at Svalbard (island faaaaaaaaar north) :)
Unfortunately, so does LED. They tested a similar rollout in Oslo recently, but had to stop when they discovered that the LEDs aged far more rapidly than the old sodium fixtures.
Source:
http://www.abcnyheter.no/nyheter/2013/06/17/her-er-grunnen-til-oslo-satte-full-stopp-pa-led-utbyttingen
In this case its not patented, but if it where, just declaring the patents invalid would be a bad idea. If they did that, european nations may also look at which patents are annoying AND held by US companies, and declare some of them invalid as well.
Basically, this isn't worth risking a trade war over, and it isn't worth starting up a production line because of it. Alternatives exsist. The EU also knows that it isn't worth the risk for the US - that's why they do it.
But is Iran using these drugs for executions? Because that's what the threathened export ban to the US is about. I doubt we're selling high-speed centrifuges (for isotope separation / nuclear weapons programs) etc. to Iran either.
Yeah. I've visited SF a few times (living in Europe), and the transit there is a sad joke. BART must be the worlds slowest subway system, CalTrain is a diesel train crossing everywhere at street level (making HOOOOT HOOOOT HOOOOOOOOOOT noises as it does), the highways are generally clogged, and inside SF its even worse. Only good thing is that CalTrain alows you to bring your bike - most sensible method of transportation inside SF, and the Marguerite shuttle network around Stanford/SLAC, which also allows you to bring a bike - excelent when you're working at SLAC on the top of the hill, while living in Menlo at the bottom of it, and the SLAC shuttle stops running before I normally leave work...
This isn't a (huge) problem in most other subway systems I've used. Never been to NY tough, so maybe people are completely different there - but I would suspect not.
Having frequent departures also helps this - missing a train isn't a big deal if there is another one comming in ~5 minutes or so, worse if you have to wait 15 or more.
Quantuum mech on simple systems != large systems. For larger systems, "normal" thermodynamics applies.
I would be surprised if everything - especially valve springs and other timing-critical parts - are just scaled dimensionally.
A better example than a engine is a pendulum, which period is 2*pi*sqrt(L/g). If you change L, the frequency changes. If this pendulum (or similar part) is part of a machine, and there are multiple such parts, which doesn't neccessarily scale the same way, you end up with parts which was syncronized at one scale, not being synchronized at another scale. For an interference engine, that would mean something like the valve not closing properly before the cylinder comes -> clash & extensive damage.
The illegality may at least discourage repair shops from publicly advertizing such services.
I've been thinking the same about US universities - they all seem to have some kind of "campus police" - is that really needed, can't you just call the normal police when needed, plus maybe have a few normal security people to switch off the lights, lock the doors, and let people who's forgotten their keys/access card in/out?
But wounded horses, especially those that where unlucky to break a leg (not easy to heal properly), end up on the table. And yes, horse meat often taste very good - more taste than beef, usually tender, and much cheaper.
At least here in France there is a nice section with horse in the supermarket next to beef etc. - I think it is actually bigger than sheep meat (opposite of my native Norway, where most supermarkets carry horse (and good ones, whale), but sheep is at least as common as cow).
Please mod parent up!
*SNIP*
BTW, this is one reason why I take all the global warming predictions with a big grain of salt - they are all based on computer simulations which are difficult if not impossible to validate, and given what I've seen, I don't trust the results from them at all.
In the case of climate simulations, different models (both physics-wise and code-wise) are run with different computers on the same input data, and yield basically the same results.
When simulation chaotic behaviour, very small differences can make a big difference in the outcome of your simulations. As an example, I'm currently working on simulations of sparks in vacuum, which is a "runaway" process. In this case, adding a single particle early in the simulations (before the spark actually happens) can change the time for the spark to appear by several tens of %. This also happens if we are running with different library versions (SuperLU, Lapack), different compilers, and different compiler flags. Once the spark happens, the behaviour is predictable and repeatable - but the time for it to happen, as the system is "balancing on the edge, before falling over", is quite random.
There are plenty of sources of coal around the world - for example Germany runs / used to run quite large coal mines.