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Comment Re:Many a young engineer.... (Score 2) 72

... every schematic drawn by every semiconductor engineer got the arrow backwards.

As I heard it, The arrow is "backward" because Benjamin Franklin, when doing his work unifying "vitreous" and "resinous" electricity as surplus and deficit of a single charge carrier (and identifying the "electrical pressure" later named "voltage"), took a guess at which corresponded to a surplus of a movable charge carrier. He had a 50% chance to assign "positive" to the TYPICAL moving charge carrier in the situations being experimented with (charge transfer by friction between different substances, currents in metallic conductors, and high voltage discharges in air and water-in-air aerosols) and happened to guess "wrong".

Thus we say electrons have a negative charge, "classical current" corresponds to the sum of the flow of moving positive charge minus the flow of negative charge (i.e. the negative of the electron current, which is all there is in normal-matter metallic conductors), the arrowhead on diodes (and junction transistors) points in the direction of classical current across a junction, and so on.

But though it's the charge carrier in metallic conduction and (hard) vacuum tubes, the electron ISN'T the only charge carrier. Even in the above list of phenomena, positive ion flow is a substantial part of electrical discharge currents in air - static sparks and lightning. Positive moving charge carriers are substantial contributors to current as you get to other plasma phenomena and technologies - gas-filled "vacuum" tubes (such as thyratons), gas an LIQUID filled "vacuum" tubes (ignatrons), gas discharge lighting, arc lighting, arc welding, prototype nuclear fusion reactors, ...

Move on to electrochemistry and ALL the charge carriers are ions - atoms or molecular groups with an unequal electron and proton count, and thus a net charge - which may be either positive or negative (and you're usually working wit a mix of both).

And then there's semiconductors, where you have both electrons and "holes" participating in metallic conduction. Yes, you can argue that hole propagation is actually electron movement. But holes act like a coherent physical entity in SO many ways that it's easier to treat them as charge carriers in their own right, with their own properties, than to drill down to the electron hops that underlie them. For starters, they're the only entity in "hole current" that maintains a long-term association with the movement of a bit of charge - any given electron is only involved in a single hop, while the hole exists from its creation (by an electron being ejected from a place in the semiconductor that an electron should be, by doping or excitation, leaving a hole) to their destruction (by a free electron falling into them and releasing the energy of electron-hole-pair separation). They move around - like a charge carrier with a very short (like usually just to the next atom of the solid material) mean free path.

For me the big tell is that they participate in the Hall Effect just as if they were a positive charge carrier being deflected by a magnetic field. The hall voltage tells you the difference between the fraction of the current carried by electrons excited into a conduction band and that carried by holes - whether you think of them as actual moving positive charge carriers or a coordinated hopping phenomenon among electrons that are still in a lower energy state. Further, much of interesting semiconductor behavior is mediated by whether electrons or holes are the "majority carrier" in a given region - exactly what the hall effect tells you about it.

So, as with many engineering phenomena, the sign for charge and current is arbitrary, and there are both real and virtual current carriers with positive charge. Saying "they got it wrong" when classical current is the reverse of electron current is just metallic/thermionic conduction chauvinism. B

Comment Re:Vacuum tubes handle EMP's better (Score 1) 72

"No point progressing since the bombs are gonna fall any day now. Then where will your fancy silicon highways and databases be?"

Given that the Internet Protocol and much of the rest of the networking technology that still underpins the Internet were developed as part of a cold-war program to create a communication system that could survive a nuclear attack that destroyed most of it, and still reorganize itself to pass messages quickly, efficiently, and automatically among any nodes that still had SOME path between them, your post seems to come from some alternate universe to the one I inhabit.

Comment Re:anti-business liberal scoring points (Score 1) 240

If they are publicly traded and their principal business is not risk, then they are required to be by law.


I'm fairly certain there is no such law. What publicly-traded businesses are required to do is to do what they say they'll do in their articles of incorporation and their prospectus. For most, these documents state that their focus is to generate a responsible return on investment (language varies, but that's what it boils down to). However, it is perfectly acceptable for them to include other goals, and even to prioritize those goals over making money.

Were SpaceX to go public, they could specify that their primary goal is to get to Mars, for example, rather than to make money. That would probably lower their valuation, but there would be nothing at all illegal about it.

Comment Re:yet more engineer bashing (Score 1) 423

The real question is not are engineers 9 times more likely to be terrorists. The real question is are they 9 times more likely to hold extremist beliefs, or just 9 times more likely to act on them because to engineers the point is to solve problems.

I suspect it's some of both. It seems to me that engineers do tend to be more passionate about their interests (whatever those may be) than the average person. And they think in terms of how to solve problems.

Comment Re:I'll believe it when I see it (Score 1) 47

And yet for all your misdirected Windows whining DirectX for Windows is the only area that AMD cards perform well. Their Linux drivers blow, as noted by other posts here, and that is because AMD can't write OpenGL drivers to save their life.

nVidia, on the other hand, has extremely fast and solid drivers for Linux.

Submission + - Why Car Salesmen Don't Want to Sell Electric Cars writes: Matt Richtel writes in the NYT that one big reason there are only about 330,000 electric vehicles on the road is that car dealers show little enthusiasm for putting consumers into electric cars. Industry insiders say that electric vehicles do not offer dealers the same profits as gas-powered cars, they take more time to sell because of the explaining required, and electric vehicles may require less maintenance, undermining the biggest source of dealer profits — their service departments. Some electric car buyers have said they felt as if they were the ones doing the selling. Chelsea Dell made an appointment to test-drive a used Volt but when she arrived, she said, a salesman told her that the car hadn’t been washed, and that he had instead readied a less expensive, gas-powered car. “I was ready to pull the trigger, and they were trying to muscle me into a Chevy Sonic,” says Dell. “The thing I was baffled at was that the Volt was a lot more expensive.” Marc Deutsch, Nissan’s business development manager for electric vehicles says some salespeople just can’t rationalize the time it takes to sell the cars. A salesperson “can sell two gas burners in less than it takes to sell a Leaf,” Deutsch says. “It’s a lot of work for a little pay.”

Jared Allen says that service is crucial to dealer profits and that dealers didn’t want to push consumers into electric cars that might make them less inclined to return for service. Maybe that helps explains the experience of Robert Kast, who last year leased a Volkswagen e-Golf from a local dealer. He said the salesman offered him a $15-per-month maintenance package that included service for oil changes, belt repair and water pumps. “I said: ‘You know it doesn’t have any of those things,’” Mr. Kast recalled. He said the salesman excused himself to go confirm this with his manager. Of the whole experience, Mr. Kast, 61, said: “I knew a whole lot more about the car than anyone in the building.” "Until selling a plug-in electric car is as quick and easy as selling any other vehicle that nets the dealer the same profit, many dealers will avoid them, for very logical and understandable reasons," says John Voelker. "That means that the appropriate question should be directed to makers of electric cars: What are you doing to make selling electric cars as profitable and painless for your dealers as selling gasoline or diesel vehicles?"

Comment Re:Those who can, program. (Score 1) 84

I apply the scientific method to figuring out how to talk to undocumented "black boxes"

Don't we all :-) But I think that is not so much programming (ie writing program code) as it is intelligent planning before you make you next move.

In mathematics, you can spend a career mentally masturbating over your favorite "hard" problem, and retire after decades with nothing to show for it. In programming, if you work on a problem for five years, you'd damned well better get world-changing results, or find a new job.

Not really - universities do in fact require any scientist to be productive. Results don't have to be of the same order of magnitude as the achievements of Einstein, Gauss, Riemann etc. to be valuable. Lots of scientific research is farily humdrum, predictable stuff, that still has a very useful function. It is largely a myth that being a scientist is some sort of sinecure; and just because the general public can't see the point of it, doesn't mean that it isn't going to be important later.

Comment Well of course, because Linux is OpenGL (Score 1) 47

And AMD can't handle OpenGL. I don't know why, I'm not sure what's so hard, I'm not sure if there's a monster that guards the OpenGL specs in the AMD office or something, but they have sucked at GL for over a decade, and show no signs of getting any better. They can't claim it is because of an API limitation either. For whatever you want to say about the mess that is OpenGL, nVidia makes their GL drivers dead even with their DX drivers. You can use either rendering path and can't tell the difference in features or speed.

That is also why I'm real skeptical that Vulkan is going to do anything for AMD. While they are heavily involved in the development, they are involved with OpenGL's development too (ATi was a voting member on the ARB and is a promoter with Khronos Group). Given that Vulkan is heavily GL based, originally being named glNext, I worry that AMD will suck at performance with it as well.

Comment I'll believe it when I see it (Score 2, Insightful) 47

Not the driver, that's out, but that they are going to change how they do drivers. They've said that numerous times before, and always the situation is the same. They are very slow at getting actual release drivers out (they are forever beta versions) and their OpenGL performance and support is garbage (to the point that HFSS would fail to run on systems with AMD cards).

So AMD: Less talk, more good drivers. I want to support you, I really do, but I've been burned too many times.

Comment 'Black Friday' - what's that? (Score 1) 135

I stoppd paying attention to Christmas, Easter, etc - even birthdays - many years ago exactly because of the commercialisation of it. The thought of gorging myself on food and drinks that I don't actually like, in the company of people that I mostly don't care about and wouldn't see at any other time, just doesn't appeal for some reason. Plus, of course, the frenzy to buy gifts that are mostly misplaced and unwanted. (Sorry, did that sound cynical?)

I very pointedly do not buy gifts for birthdays or Christmas; instead I buy useful things for people I want to give something special - my wife and children, mostly - on days throughout the year. My form of protest - childish, you might say, but that's how I stay young ;-)

Be careful when a loop exits to the same place from side and bottom.