My car can "fly" for 4 hours at 110 mph, and it often does, too. Any particular reason for wanting to go half the speed, quarter as far, just because it's above ground?
They are 3 times cheaper, and come fully charged, as opposed to NiMH, which you have to charge for hours before use. Disposable batteries in high-drain devices are an emergency solution.
I stopped using flashblock -- those "f" icons are so tempting, and for clicking them you get to see an ad, 99.9% of the time. I just adblock the fuckers, along with the rest of their ad server. Amazimgly, about 80% of the ad content on the internet is served by the same 10 or 20 servers, so adblock works very well even if you don't load a fancy filterset. Sadly, however, some companies serve their ad contents from the same servers as their pages.
This is what I don't understand. The working cycle in a fuel-powered engine is:
1. compress 2. heat up 3. release pressure and temp, take energy
This is not very efficient. The efficiency depends on compression ratio, basically, and tops out at some 40%.
A compressed air engine's cycle is:
1. compress 2. cool down in tank 3. release pressure while heating the working body with ambient heat as much as possible, take energy
This is way less efficient than even a heat engine, as much energy is going into the cooling of the exhaust. A car based on this won't need an air conditioner, though:-).
As for LCDs, you're mistaken -- if it's analog (and most still are) then a poor quality signal decoder can result in bleed between pixels, which tends to make them look blurry. Another possibility when using low-quality decoders, or refresh frequencies higher than the decoder can tolerate, is pixel shimmer.
True enough... I was thinking of laptop LCDs. Though I haven't really seen a flickering analog desktop LCD in about two years now. They got better lately. I've had a good experience with Samsung desktop LCDs lately - nice and cheap.
Most color DLPs flicker, because of the color wheel. I'm sure there are some that use 3 projectors instead, though.
Most LCD panels can not be blurry, because the individual pixels are actually electrodes drawn on the inside of the glass with conductive material. I'm sure it would be possible to make an LCD panel that would be blurry on purpose, but naturally they have perfect geometry and focus. Your employer must've had to work hard to find a source of LCD panels that are blurry. Would you care to tell us who your employer get these blurry LCDs from?
You need to transmit enough power to the chip to bring up its transmitter. Low-frequency tags use a 125kHz magnetic field for that. The field is transmitted by a coil antenna in the reader. The transmitter replies by modulating the field, i.e. by connecting a resistor across its little antenna coil. This modulation is very feeble.
Since a reasonably sized 125 kHz magnetic antenna could hardly be made directional, for long range scanning you'd need to create a strong and large field with a large high-power coil, but then you couldn't detect the modulation reliably. A small low-power reader coil in direct proximity of the chip has a much better S/N ratio, but it has to be close to the chip to work.
In other words, it would be very difficult to create a long-range reader, for technical reasons.
...and asks that PSP owners use theirs for at least a week or two, to see if it still bothers them.
As far as I remember that worked really well for Intel, with the division bug. Try to use your new CPU for a week or two, see if the division bug really bothers you. YEAH, RIGHT... I have two words for you, Sony -- PSP KEYCHAIN!
Note to the RIAA/MPAA: profit from P2P, instead of trying to fight it.
How cah they do it? Embracing p2p won't help them keep their 80% margins.
The situation that allowed them to have those margins was only temporary, even though it lasted almost a 100 years, and was mainly due to the lack of technical means to distribute copies of quality music in small production runs. Now the distribution is not a problem anymore, any musician can put mp3s online. Promotion is still a problem, and the copyright law allows the labels to get an ROI on promotion.
But the margins that they have are completely unnatural and unwarranted. Those margins need to go down. The public does not support them. The public pirates the mp3s off p2p networks and copies CDs from friends. In the interest of the public the copyright law would have to be change, making arbitrary pricing impossible somehow. Instead the labels are now succeeding in increasing the enforcement of the obsolete law to a degree that it is already threatening free speech rights.
And I keep wondering how long the freedom-loving public of the U.S will put up with this crap. So far the public seems ignorant of the problem.
There are several unnecessary extras that the Windows install won't let you skip (AFAIK Windows 95 was the last release that did). Outlook express, Windows Movie Maker, IE, Media player, the CD recording capability... that stupid xerox directory...
The only component that's actually necessary is the IE rendering libraries. Those are used for some UI dialogs and help.
But you can't really sell something like a Windows web browser anymore, you have to give it away. As a result, it's harder to make money on something like this. As far as the users are concerned, there are fewer high quality commercial choices, but better-quality free stuff is available. The free stuff is usually cross-platform, which means that by bundling commodity apps with Windows MS actually prompts free software development in a wierd way.
I don't know what edge MS makes by making it impossible to skip installing the free stuff, but it definitely makes some users angry. I know of some cases when Windows was rejected as a platform choice for a embedded projects because it was impossible to create a custom limited install. In one case a project ended up being implemented with linux because of this, even though technically Windows XP would've been a more natural choice.
A good UPS, yes. There is the kind of UPS that always stabilizes the output, they are usually quite expensive. The more common kind of UPS only kicks in if the input fails. Depending on how fast it kicks in it could be useful in protecting your equipment, or not.
I can think of a few ways, but they all would be too involved unless you were about to order a 1000 PSUs for a production run.
Cracking it open and looking at the quality of the PCB fabrication (lack of hand soldering) would be my #1. Hand-soldering usually means cold solder joints in some of the units.
A DESTRUCTIVE test for brown-out response would be quite easy - just load the supply to the rated max, then lower the input voltage. The thing should shut down, and not blow up. Of course, this test would only be destructive to a supply that wasn't worth its name in the first place. Vary the speed with which you lower the voltage.
Another test you could do would be to hook up a scope to the output, and look at how it responds to spikes/dips in the input. If there are any spikes at all, especially in the UP direction, it's no good.
Now, IANA-electrical-engineer. Not all electrical engineers can properly design and test PSUs either, even though the PSU design is usually consireded a low-grade job that's given to an out-of-school junior EE as a "training" excercise. The truth is that you never get hailed a hero for designing a good PDU, yet designing one is quite involved.
Do you have any reason to believe that the power supply that comes with a $40 case is more likely to fail than a more expensive one?
Yes. My sample included 10 computers with hardware failures, about a half of them with cheapo PSUs. 3 of the failures were due to a PSU blowing up, all 3 being of the the cheapo variety.
One of the PSUs took the motherboard with it, and another took a hard drive full of data, and, by some strange fluke, a DIMM socket and a DIMM (the rest of the motherboard still works). This is not real statistics, mind you, but it gives you an idea.
==
A typical failure mechanism is like this. Cheap PSUs can't make it through a brown-out. The H-bridge transistors have to pass higher current to compensate for the lower input voltage, and start to overheat. A good PSU would use heftier transistors, and the controller would shut it down if the voltage dips too low.
In a lousy cheap PSU one of the FETs reaches the point where the silicon starts to melt, and it becomes permanently conductive. Then, the controller switches the bridge, causing a through current that melts the other FET in the same side of the bridge. One of the FETs then vapourizes with a loud bang, leaving a visible crack in the plastic case of the FET. During all this the current through the transformer gets switched chaotically, causing spikes in the secondary windings, and killing the cheap underrated regulators in the secondary circuits, which then pass the spikes to your expensive components. Something like that.
Another problem with poorly built PSUs is that the irregularities in the input sometimes make it to the output, causing crashes and hang-ups. If you want to build a stable system, start with a high quality PSU. It doesn't have to be expensive. Just pick one from a company whose name you (or your friends) recognize.
I've had to fix about 30 computers last year, and about 10 of them had problems caused by faulty power supplies and failing drives, both hard and optical. Power supplies are particularly nasty when they fail, since they often take other components with them. If you build your own box, rip out the supply that comes with your $40 case, and buy a good one.
One box was stepped on, resulting in some connectors ripped out of the motherboard, and was partially fixed by soldering them back on.
The rest of the machines were crippled by malware, which in 70% cases could not be removed automatically and had to be hunted down and exterminated by hand, leaving behind dead pieces of it n many cases. Only one machine had to be reinstalled (I'm sooo good!).
On all those machines I hid IE from the menus and installed firefox, and explained to the users why they should use it. I've only had two repeat calls so far. Both users were web designers who had to have IE available for work, and also had random relatives and friends using their computers for mail, web and itunes. Can't help there:-).
It most definitly is worth doing, and there are thousands of people working on natural language understanding (me included:-). The results are promising, but with the current state of the art it's not possible to make a usable general purpose grammar checker, and it won't be possible for at least another 5 years of research. Or maybe 15. Grammar checkers will be getting better, but they will not become usable for a long while yet.
In other words, anyone who tries to implement a grammar checker in a word processing program now, is not doing it in a good faith, unless he's naive and ignorant. M$ did not put a grammar checker in M$ Word in good faith either -- they did it for marketing reasons.
A friend of mine ran crack over/etc/passwd on his physics department's unix system, successfully cracking 20% of the passwords on file. He sent the results to his sysadmin, with a note asking the sysadmin to implement crack system-wide, and was promptly reprimanded.
On VAX VMS you had to pick a password from a list of randomly generated "pronouncable" strings, if I recall correctly. On many properly-managed UNIX installations the crack program is used to check the user's passwords and will not allow you to use a crackable one. Is there as option to allow only hard passwords on Windows? I honestly don't know...
On the whole, soft password problem seems like a healthy n00b-usability-over-security type thing.
There is no decent grammar checker, period. It's impossible to make one. Takes too much AI; you need to actually understand the text to parse the grammar correctly. It could be possible to make a grammar checker for some very formal and small subset of English. A general grammar checker to be built into a wordprocessor is impossible. The one in M$ Word was a marketing gimmick; it was never seriously supposed to work; it couldn't have been.
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My car can "fly" for 4 hours at 110 mph, and it often does, too. Any particular reason for wanting to go half the speed, quarter as far, just because it's above ground?
Heck, Bush is not that popular either. At least Carter didn't have rotten eggs thrown at his limo on his innaguration day.
What if you incorporate in outer mongolia?
They are 3 times cheaper, and come fully charged, as opposed to NiMH, which you have to charge for hours before use. Disposable batteries in high-drain devices are an emergency solution.
I stopped using flashblock -- those "f" icons are so tempting, and for clicking them you get to see an ad, 99.9% of the time. I just adblock the fuckers, along with the rest of their ad server. Amazimgly, about 80% of the ad content on the internet is served by the same 10 or 20 servers, so adblock works very well even if you don't load a fancy filterset. Sadly, however, some companies serve their ad contents from the same servers as their pages.
That is why when you take your car in to have gas tank work (with torch/weld not epoxy) they have you fill up the tank.
I thought they fill it up with water. Try to visualise welding on a tank full of gasoline, you will understand why...
This is what I don't understand. The working cycle in a fuel-powered engine is:
1. compress
2. heat up
3. release pressure and temp, take energy
This is not very efficient. The efficiency depends on compression ratio, basically, and tops out at some 40%.
A compressed air engine's cycle is:
1. compress
2. cool down in tank
3. release pressure while heating the working body with ambient heat as much as possible, take energy
This is way less efficient than even a heat engine, as much energy is going into the cooling of the exhaust. A car based on this won't need an air conditioner, though:-).
As for LCDs, you're mistaken -- if it's analog (and most still are) then a poor quality signal decoder can result in bleed between pixels, which tends to make them look blurry. Another possibility when using low-quality decoders, or refresh frequencies higher than the decoder can tolerate, is pixel shimmer.
True enough... I was thinking of laptop LCDs. Though I haven't really seen a flickering analog desktop LCD in about two years now. They got better lately. I've had a good experience with Samsung desktop LCDs lately - nice and cheap.
Most color DLPs flicker, because of the color wheel. I'm sure there are some that use 3 projectors instead, though.
Most LCD panels can not be blurry, because the individual pixels are actually electrodes drawn on the inside of the glass with conductive material. I'm sure it would be possible to make an LCD panel that would be blurry on purpose, but naturally they have perfect geometry and focus. Your employer must've had to work hard to find a source of LCD panels that are blurry. Would you care to tell us who your employer get these blurry LCDs from?
Is this an actual real article?
Who knows... Is this an actual real first post? I don't think so...
a good way to hold all these batteries together.
Duct tape, perhaps?
You need to transmit enough power to the chip to bring up its transmitter. Low-frequency tags use a 125kHz magnetic field for that. The field is transmitted by a coil antenna in the reader. The transmitter replies by modulating the field, i.e. by connecting a resistor across its little antenna coil. This modulation is very feeble.
Since a reasonably sized 125 kHz magnetic antenna could hardly be made directional, for long range scanning you'd need to create a strong and large field with a large high-power coil, but then you couldn't detect the modulation reliably. A small low-power reader coil in direct proximity of the chip has a much better S/N ratio, but it has to be close to the chip to work.
In other words, it would be very difficult to create a long-range reader, for technical reasons.
You'd do well installing your Windows 98 on... maybe, in... it.
...and asks that PSP owners use theirs for at least a week or two, to see if it still bothers them.
As far as I remember that worked really well for Intel, with the division bug. Try to use your new CPU for a week or two, see if the division bug really bothers you. YEAH, RIGHT... I have two words for you, Sony -- PSP KEYCHAIN!
Note to the RIAA/MPAA: profit from P2P, instead of trying to fight it.
How cah they do it? Embracing p2p won't help them keep their 80% margins.
The situation that allowed them to have those margins was only temporary, even though it lasted almost a 100 years, and was mainly due to the lack of technical means to distribute copies of quality music in small production runs. Now the distribution is not a problem anymore, any musician can put mp3s online. Promotion is still a problem, and the copyright law allows the labels to get an ROI on promotion.
But the margins that they have are completely unnatural and unwarranted. Those margins need to go down. The public does not support them. The public pirates the mp3s off p2p networks and copies CDs from friends. In the interest of the public the copyright law would have to be change, making arbitrary pricing impossible somehow. Instead the labels are now succeeding in increasing the enforcement of the obsolete law to a degree that it is already threatening free speech rights.
And I keep wondering how long the freedom-loving public of the U.S will put up with this crap. So far the public seems ignorant of the problem.
There are several unnecessary extras that the Windows install won't let you skip (AFAIK Windows 95 was the last release that did). Outlook express, Windows Movie Maker, IE, Media player, the CD recording capability... that stupid xerox directory...
The only component that's actually necessary is the IE rendering libraries. Those are used for some UI dialogs and help.
But you can't really sell something like a Windows web browser anymore, you have to give it away. As a result, it's harder to make money on something like this. As far as the users are concerned, there are fewer high quality commercial choices, but better-quality free stuff is available. The free stuff is usually cross-platform, which means that by bundling commodity apps with Windows MS actually prompts free software development in a wierd way.
I don't know what edge MS makes by making it impossible to skip installing the free stuff, but it definitely makes some users angry. I know of some cases when Windows was rejected as a platform choice for a embedded projects because it was impossible to create a custom limited install. In one case a project ended up being implemented with linux because of this, even though technically Windows XP would've been a more natural choice.
A good UPS, yes. There is the kind of UPS that always stabilizes the output, they are usually quite expensive. The more common kind of UPS only kicks in if the input fails. Depending on how fast it kicks in it could be useful in protecting your equipment, or not.
If you were cracking passwords on my box, I'd reprimand you too.
I bet you wouldn't leave it unshadowed either.
There are usually enough security problems with hackers on a well-secured system to leave gaping holes like that open.
How can you check for a cheap power supply?
I can think of a few ways, but they all would be too involved unless you were about to order a 1000 PSUs for a production run.
Cracking it open and looking at the quality of the PCB fabrication (lack of hand soldering) would be my #1. Hand-soldering usually means cold solder joints in some of the units.
A DESTRUCTIVE test for brown-out response would be quite easy - just load the supply to the rated max, then lower the input voltage. The thing should shut down, and not blow up. Of course, this test would only be destructive to a supply that wasn't worth its name in the first place. Vary the speed with which you lower the voltage.
Another test you could do would be to hook up a scope to the output, and look at how it responds to spikes/dips in the input. If there are any spikes at all, especially in the UP direction, it's no good.
Now, IANA-electrical-engineer. Not all electrical engineers can properly design and test PSUs either, even though the PSU design is usually consireded a low-grade job that's given to an out-of-school junior EE as a "training" excercise. The truth is that you never get hailed a hero for designing a good PDU, yet designing one is quite involved.
Do you have any reason to believe that the power supply that comes with a $40 case is more likely to fail than a more expensive one?
Yes. My sample included 10 computers with hardware failures, about a half of them with cheapo PSUs. 3 of the failures were due to a PSU blowing up, all 3 being of the the cheapo variety.
One of the PSUs took the motherboard with it, and another took a hard drive full of data, and, by some strange fluke, a DIMM socket and a DIMM (the rest of the motherboard still works). This is not real statistics, mind you, but it gives you an idea.
==
A typical failure mechanism is like this. Cheap PSUs can't make it through a brown-out. The H-bridge transistors have to pass higher current to compensate for the lower input voltage, and start to overheat. A good PSU would use heftier transistors, and the controller would shut it down if the voltage dips too low.
In a lousy cheap PSU one of the FETs reaches the point where the silicon starts to melt, and it becomes permanently conductive. Then, the controller switches the bridge, causing a through current that melts the other FET in the same side of the bridge. One of the FETs then vapourizes with a loud bang, leaving a visible crack in the plastic case of the FET. During all this the current through the transformer gets switched chaotically, causing spikes in the secondary windings, and killing the cheap underrated regulators in the secondary circuits, which then pass the spikes to your expensive components. Something like that.
Another problem with poorly built PSUs is that the irregularities in the input sometimes make it to the output, causing crashes and hang-ups. If you want to build a stable system, start with a high quality PSU. It doesn't have to be expensive. Just pick one from a company whose name you (or your friends) recognize.
Well, the people trying to hack into your system remotely won't be able to look under the keyboard.
I've had to fix about 30 computers last year, and about 10 of them had problems caused by faulty power supplies and failing drives, both hard and optical. Power supplies are particularly nasty when they fail, since they often take other components with them. If you build your own box, rip out the supply that comes with your $40 case, and buy a good one.
One box was stepped on, resulting in some connectors ripped out of the motherboard, and was partially fixed by soldering them back on.
The rest of the machines were crippled by malware, which in 70% cases could not be removed automatically and had to be hunted down and exterminated by hand, leaving behind dead pieces of it n many cases. Only one machine had to be reinstalled (I'm sooo good!).
On all those machines I hid IE from the menus and installed firefox, and explained to the users why they should use it. I've only had two repeat calls so far. Both users were web designers who had to have IE available for work, and also had random relatives and friends using their computers for mail, web and itunes. Can't help there:-).
That it's hard just means it's worth doing.
It most definitly is worth doing, and there are thousands of people working on natural language understanding (me included:-). The results are promising, but with the current state of the art it's not possible to make a usable general purpose grammar checker, and it won't be possible for at least another 5 years of research. Or maybe 15. Grammar checkers will be getting better, but they will not become usable for a long while yet.
In other words, anyone who tries to implement a grammar checker in a word processing program now, is not doing it in a good faith, unless he's naive and ignorant. M$ did not put a grammar checker in M$ Word in good faith either -- they did it for marketing reasons.
A friend of mine ran crack over /etc/passwd on his physics department's unix system, successfully cracking 20% of the passwords on file. He sent the results to his sysadmin, with a note asking the sysadmin to implement crack system-wide, and was promptly reprimanded.
On VAX VMS you had to pick a password from a list of randomly generated "pronouncable" strings, if I recall correctly. On many properly-managed UNIX installations the crack program is used to check the user's passwords and will not allow you to use a crackable one. Is there as option to allow only hard passwords on Windows? I honestly don't know...
On the whole, soft password problem seems like a healthy n00b-usability-over-security type thing.
There is no decent grammar checker, period. It's impossible to make one. Takes too much AI; you need to actually understand the text to parse the grammar correctly. It could be possible to make a grammar checker for some very formal and small subset of English. A general grammar checker to be built into a wordprocessor is impossible. The one in M$ Word was a marketing gimmick; it was never seriously supposed to work; it couldn't have been.