Apart from the obvious issue with appliances, there's another reason.
Mains 240V AC switches are not rated for that kind of DC voltage - the arc from switching DC at those voltages will most likely destroy the switch. This arc is only brief with AC at 50/60 Hz as the arc will extinguish when the voltage drops to zero every half-cycle.
This is why switches are normally rated along the lines of "240VAC/32VDC"
Music CDR's are "special" CD's that are only for use in audio cd recorders (a standalone unit, as opposed to the burner in your PC).
Audio CD recorders will normally refuse to record onto data CDR's, obligating you to buy the more expensive Audio-CDR so you can record all your filthy pirated works, you filthy pirate,you:-)
Those all all good engineering points, but sadly, higher combustion temperatures mean more NOx. So, the overall engineering intent is to find the sweet spot between NOx production and efficiency... which leads to losses in performance and fuel economy.
You are probably thinking of the system where an air pump pumps air into the exhaust system to burn off the residual fuel products. This page gives a pretty good overview of emission control systems on cars.
Breakfast Pants, Thank you for your completely incorrect post. Now go sit in the corner and get educated:-)
In your car's engine, Nitrogen in the air combines with Oxygen in air to create oxides of nitrogen, commonly called NOx for brevity.
How does it combine? The heat of combustion of the fuel in the engine is sufficient to do it. Lean-running engines that run hotter (well, have a longer burning flame front), while more fuel efficient, also have the unfortunate problem of creating more oxides of nitrogen.
It doesn't matter what you burn in there, any combustion temperatures over a thousand degrees C or so has sufficient energy to drive the NOx chemical reaction. Petrol, Diesel, Hydrogen... all of those fuels indirectly produce NOx.
The goal in modern cars is to lower the combustion chamber temperatures, which is why most cars have some form of exhaust gas recirculation to deliberately "posion" the incoming air/fuel mix to make it burn cooler. Fuel economy suffers as a result of reducing NOx emissons.
You might have a counterweight+spring on the rotor in your distributor. You can tell by taking the distributor cap off and pulling off the rotor - you can normally see a spring arrangement of sorts on the rotor.
Early carburetted Landcruisers had this - when you got to about 5000rpm (500rpm above redline) there was enough centripetal force on it for it to be moved out a little, which shorted out your spark to the distributor shaft. This stopped all sorts of valve-bending hilarity from happening. I know, as an apprentice friend of mine found a cruiser that had one that didn't work, and proceeded to deliberately thrash and rev it off the tacho, above 6000RPM. Strangely enough , when he got it back to the workshop, it was running a little rough.
Note that "Park" (on most auto transmissions) only has a dinky little rod that gets inserted into the teeth of one of your gear packs to stop it from rotating.
Stops your car from rolling away on a hill? Yes.
Stops your car from 60MPH? *small crunching noise* No.
I dunno, your power requirements seem to be a little on the high side.
Eg. 1 horsepower is 750W. An average human can sustain about 200W continuous. So on a flat road, or average slopes (depending on extra weight) a single 1HP motor should give you at least more speed than what your average person can put out.
If only the person doing 80 would stop and say "Is my life worth thinking I could get away with doing 80 in a 60 zone?"
Normally they only think this in the few seconds before they and their vehicle is mangled horribly beyon repair. Straight line control is decptively easy, so everyone speeds. Having to rapidly evade a child, shredded tyre, errant cow etc at 80mph often ends up with you, or somebody else, seriously injured.
Roads are designed for the lowest common denominator of driver. Just because you think you may have supreme ability in controlling your vehicle in all conditions doesn't mean that everyone else believes the same thing.
Take a defensive driving course and see just how little control of your vehicle you actually have at 80mph in good conditions, let alone marginal ones.
It just reminds me of that Simpson's episode about the Stonecutters with Patrick Stewart - where he says "And now, the final ordeal: the 'paddling of the swollen ass' - with paddles!"
It is the most powerful events ever witnessed. Such collisions are second only to the Big Bang in total energy output. The event was captured with the European Space Agency's XMM-Newton observatory. Scientists are calling the event the perfect cosmic storm
There's issues with the implied past tense in this story - this 'event' is still continuing and will do so for many millions of years to come. The impression is that a whole pile of galaxies just had a massive fender-bender and now it's all over.
I don't know about your definition of "entire country" , but it obviously doesn't mesh with mine. I can drive from Mount Isa to Townsville (approx 900km) and have about 500km of that trip with *no* signal, GSM or CDMA.
There's plenty of self-aggrandizing ads that proudly proclaim "Now covering 97% of the population!!". They don't mention the many hundreds-of-kilometer gaps in coverage where people frequent (eg major highways), but where nobody lives. So, all you people that bitch about how your cellphone drops out all the time, consider yourselves lucky that you get service at all.
Look at me! I'm all bitter and twisted over fricken PHONE COVERAGE! Maybe I'll just go and have a lie down for a while:-)
A lot of off-road equipment already have foam-filled or "airless" tyres.
The difficulty is that you can't adjust the foam compound inside the tyre - once you've filled that tyre and the foam is set that's it. If it's too hard, well, too bad.
The underground mine that I work at trialled some tyres for their light vehicles (toyota utes and such), as we regularly tear up tyres on rocks and sharp objects.
The main problems we found were:
Cost - they were AUD600 or so *each*. But they don't go flat, of course:-)
Ride quality- you could tell the vehicles with the foam-filled tyres straight away - they were ABSOLUTELY ROCK SOLID.
Weight - Think about the average volume of a tyre. The tyres on our vehicles were about 60kg each. That's a fair bit more unsprung weight rattling around and loading up your suspension components. The vehicles we trialled them on became noticeably "rattlier" in the suspension over the course of a month. "rattlier" to the point of people saying "what the hell is that noise? Oh , it's just the toyota going by."
They also trialled them on our heavy equipment, but again , they were too hard on the suspension components, even after trying half a dozen different fill compounds. A worrying number of cracks appeared in the bodies of our trial haul trucks as well... so they decided to can that idea.
But hey, you know the relentless march of technology, maybe they'll sort it out. Still think they'd be too heavy for my liking - one of the goals of getting good suspension is to reduce unsprung weight (mag wheels, drilled rotors, etc) and adding another 20kg of extra rubber compound on each wheel aint gonna help.
My MythTV box records directly into mpeg4, at PAL (720x576) resolution at a bitrate of 3Mbps - with no jitters or frame drops. And the qualitys pretty good with a good signal to encode - there's no visible artifacts on my 26" tv.
This is with an AthlonXP 2000+ processor and a generic BTTV card on a nforce based chipset.
At that bitrate, I get about 1.2GB an hour for TV. I've a number of preset recording modes, for example using a "Medium" setting I can drop it back down to 640x480 at 800MB an hour. I've a "Low" setting at VCD resolution and 500MB/hr for the kids cartoons.
And of course there's the option of automagically ripping your rental DVD's to disk via a two-pass xvid encoder for instant viewing later.... but I'm sure no-one does that:-)
Re:Those stats don't really mean much though
on
Mock World Vote
·
· Score: 1
Aren't all elections self-selected samples? By definition?
Only if your country doesn't have mandantory voting. Oh, the US doesn't? Oh dear.
They already do - you generally have a (small) percentage of readdressable memory on-chip, and when they test the chip, they 'blow' the address circuitry for any bad memory (in a similar fashion to PROMS) and then map the address lines for the backup memory cells to the bad memory location.
Or something like that, anyway. But it's all done in hardware, so there's no on-the-fly remapping done - it's all hard-wired address circuits.
I like the memory exclusion patches to linux - they take the output from memtest86 and at boot the kernel immediately allocates that memory permanently. This allow you to use your bad ram chips, minus the bad ram of course.
So, everyone, send me your bad 512MB sticks... i'll find a home for them:-)
Slashdot Mirror
Unix? Probably not even circumcised. Savages.
For all the posters in this thread :
DO NOT USE HIGH VOLTAGE DC IN YOUR HOUSE.
Apart from the obvious issue with appliances, there's another reason.
Mains 240V AC switches are not rated for that kind of DC voltage - the arc from switching DC at those voltages will most likely destroy the switch. This arc is only brief with AC at 50/60 Hz as the arc will extinguish when the voltage drops to zero every half-cycle.
This is why switches are normally rated along the lines of "240VAC/32VDC"
Music CDR's are "special" CD's that are only for use in audio cd recorders (a standalone unit, as opposed to the burner in your PC).
:-)
Audio CD recorders will normally refuse to record onto data CDR's, obligating you to buy the more expensive Audio-CDR so you can record all your filthy pirated works, you filthy pirate,you
Those all all good engineering points, but sadly, higher combustion temperatures mean more NOx. So, the overall engineering intent is to find the sweet spot between NOx production and efficiency... which leads to losses in performance and fuel economy.
And Exhaust gas Recirculation *IS* used primarily for NOx reduction.
You are probably thinking of the system where an air pump pumps air into the exhaust system to burn off the residual fuel products. This page gives a pretty good overview of emission control systems on cars.
Breakfast Pants, Thank you for your completely incorrect post. :-)
Now go sit in the corner and get educated
In your car's engine, Nitrogen in the air combines with Oxygen in air to create oxides of nitrogen, commonly called NOx for brevity.
How does it combine? The heat of combustion of the fuel in the engine is sufficient to do it. Lean-running engines that run hotter (well, have a longer burning flame front), while more fuel efficient, also have the unfortunate problem of creating more oxides of nitrogen.
It doesn't matter what you burn in there, any combustion temperatures over a thousand degrees C or so has sufficient energy to drive the NOx chemical reaction. Petrol, Diesel, Hydrogen... all of those fuels indirectly produce NOx.
The goal in modern cars is to lower the combustion chamber temperatures, which is why most cars have some form of exhaust gas recirculation to deliberately "posion" the incoming air/fuel mix to make it burn cooler. Fuel economy suffers as a result of reducing NOx emissons.
It's just everytime I go to the clubs with a beanie, I get turned away.
:-)
[jamacian accent]
you're just going to the wrong clubs, mon
Coal *is* a clean renewable resource, it's just got a 100 million year cycle :-)
You might have a counterweight+spring on the rotor in your distributor. You can tell by taking the distributor cap off and pulling off the rotor - you can normally see a spring arrangement of sorts on the rotor.
Early carburetted Landcruisers had this - when you got to about 5000rpm (500rpm above redline) there was enough centripetal force on it for it to be moved out a little, which shorted out your spark to the distributor shaft. This stopped all sorts of valve-bending hilarity from happening. I know, as an apprentice friend of mine found a cruiser that had one that didn't work, and proceeded to deliberately thrash and rev it off the tacho, above 6000RPM. Strangely enough , when he got it back to the workshop, it was running a little rough.
Note that "Park" (on most auto transmissions) only has a dinky little rod that gets inserted into the teeth of one of your gear packs to stop it from rotating.
Stops your car from rolling away on a hill? Yes.
Stops your car from 60MPH? *small crunching noise* No.
I dunno, your power requirements seem to be a little on the high side.
Eg. 1 horsepower is 750W. An average human can sustain about 200W continuous. So on a flat road, or average slopes (depending on extra weight) a single 1HP motor should give you at least more speed than what your average person can put out.
If only the person doing 80 would stop and say "Is my life worth thinking I could get away with doing 80 in a 60 zone?"
Normally they only think this in the few seconds before they and their vehicle is mangled horribly beyon repair. Straight line control is decptively easy, so everyone speeds. Having to rapidly evade a child, shredded tyre, errant cow etc at 80mph often ends up with you, or somebody else, seriously injured.
Roads are designed for the lowest common denominator of driver. Just because you think you may have supreme ability in controlling your vehicle in all conditions doesn't mean that everyone else believes the same thing.
Take a defensive driving course and see just how little control of your vehicle you actually have at 80mph in good conditions, let alone marginal ones.
It just reminds me of that Simpson's episode about the Stonecutters with Patrick Stewart - where he says "And now, the final ordeal: the 'paddling of the swollen ass' - with paddles!"
It is the most powerful events ever witnessed. Such collisions are second only to the Big Bang in total energy output. The event was captured with the European Space Agency's XMM-Newton observatory. Scientists are calling the event the perfect cosmic storm
There's issues with the implied past tense in this story - this 'event' is still continuing and will do so for many millions of years to come. The impression is that a whole pile of galaxies just had a massive fender-bender and now it's all over.
don't bother - it's crap.
I don't know about your definition of "entire country" , but it obviously doesn't mesh with mine. I can drive from Mount Isa to Townsville (approx 900km) and have about 500km of that trip with *no* signal, GSM or CDMA.
:-)
There's plenty of self-aggrandizing ads that proudly proclaim "Now covering 97% of the population!!". They don't mention the many hundreds-of-kilometer gaps in coverage where people frequent (eg major highways), but where nobody lives. So, all you people that bitch about how your cellphone drops out all the time, consider yourselves lucky that you get service at all.
Look at me! I'm all bitter and twisted over fricken PHONE COVERAGE! Maybe I'll just go and have a lie down for a while
A lot of off-road equipment already have foam-filled or "airless" tyres.
:
:-)
The difficulty is that you can't adjust the foam compound inside the tyre - once you've filled that tyre and the foam is set that's it. If it's too hard, well, too bad.
The underground mine that I work at trialled some tyres for their light vehicles (toyota utes and such), as we regularly tear up tyres on rocks and sharp objects.
The main problems we found were
Cost - they were AUD600 or so *each*. But they don't go flat, of course
Ride quality- you could tell the vehicles with the foam-filled tyres straight away - they were ABSOLUTELY ROCK SOLID.
Weight - Think about the average volume of a tyre. The tyres on our vehicles were about 60kg each. That's a fair bit more unsprung weight rattling around and loading up your suspension components. The vehicles we trialled them on became noticeably "rattlier" in the suspension over the course of a month. "rattlier" to the point of people saying "what the hell is that noise? Oh , it's just the toyota going by."
They also trialled them on our heavy equipment, but again , they were too hard on the suspension components, even after trying half a dozen different fill compounds. A worrying number of cracks appeared in the bodies of our trial haul trucks as well... so they decided to can that idea.
But hey, you know the relentless march of technology, maybe they'll sort it out. Still think they'd be too heavy for my liking - one of the goals of getting good suspension is to reduce unsprung weight (mag wheels, drilled rotors, etc) and adding another 20kg of extra rubber compound on each wheel aint gonna help.
My MythTV box records directly into mpeg4, at PAL (720x576) resolution at a bitrate of 3Mbps - with no jitters or frame drops. And the qualitys pretty good with a good signal to encode - there's no visible artifacts on my 26" tv.
:-)
This is with an AthlonXP 2000+ processor and a generic BTTV card on a nforce based chipset.
At that bitrate, I get about 1.2GB an hour for TV.
I've a number of preset recording modes, for example using a "Medium" setting I can drop it back down to 640x480 at 800MB an hour. I've a "Low" setting at VCD resolution and 500MB/hr for the kids cartoons.
And of course there's the option of automagically ripping your rental DVD's to disk via a two-pass xvid encoder for instant viewing later.... but I'm sure no-one does that
Aren't all elections self-selected samples? By definition?
Only if your country doesn't have mandantory voting.
Oh, the US doesn't? Oh dear.
That's the sound of thousands of snooty frenchmen spraying wine out through their noses.
They already do - you generally have a (small) percentage of readdressable memory on-chip, and when they test the chip, they 'blow' the address circuitry for any bad memory (in a similar fashion to PROMS) and then map the address lines for the backup memory cells to the bad memory location.
:-)
Or something like that, anyway. But it's all done in hardware, so there's no on-the-fly remapping done - it's all hard-wired address circuits.
I like the memory exclusion patches to linux - they take the output from memtest86 and at boot the kernel immediately allocates that memory permanently. This allow you to use your bad ram chips, minus the bad ram of course.
So, everyone, send me your bad 512MB sticks... i'll find a home for them
Personally, I agree with you, I just don't think Arnie will though.
I'd think he'd say it more along the lines of:
"eeekhonomhic gihrrly mahn"
No.
Vibrations through the earth travel at many kilometers per second, depending on density.
There'd be a delay (thats how you can triangulate earthquakes and such) but not in the order of 9 hours.
But they would just be below average college attendees , not graduates - as you have to be above average to graduate.
A good toast :
"To Pure Mathematics - may it never have any practical use!"
someone's gonna have to pay for those robots, ya know :-)