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Submission + - Japanese company makes low calorie noodles out of wood

AmiMoJo writes: Omikenshi Co, an Osaka based cloth manufacturer best known for rayon, a fibre made from tree pulp, is expanding into the health food business. Using a similar process, Omikenshi is turning the indigestible cellulose into a pulp that’s mixed with konjac, a yam-like plant grown in Japan. The resulting fibre-rich flour, which the company calls “cell-eat,” contains no gluten, no fat and almost no carbohydrate. It has just 60 calories a kilogram, compared with 3,680 for wheat.

Comment Re:I'm not sure this is as bad as it sounds (Score 1) 63

For example a small transaction over may cards maybe totally unnoticeable.

Also wouldn't be economical for the criminals. Stealing card details or buying them on black markets is not free. There is risk involved in every transaction, especially if it is made to look non-suspicious. Taking amounts small enough for people not to notice in a way that won't get you caught when a small percentage of them do flag it up will probably lose you money.

Comment Re:Not too hard (Score 1) 63

Indeed, the signing part is the security flaw. Card numbers on European cards are fairly predictable, usually being only a few digits different to your old card. It doesn't matter though because you can't buy anything without a PIN number or the chip part, or if online without the CVV code on the back which isn't predictable.

Comment Another useful vacuum tube: Thermionic converter. (Score 1) 92

Another vacuum tube technology with current applications and substantial advantages over semiconductor approaches to the same problems is the Thermionic Converter. This is a vacuum-tube technology heat engine that turns temperature differences into electric power - by boiling electrons off a hot electrode and collecting them, at a somewhat more negative voltage (like 0.5 to 1 volt), at a cooler electrode.

Semiconductor approaches such as the Peltier Cell tend to be limited in operating temperature due to the materials involved, and lose a major fraction of the available power to non-power-producing heat conduction from the hot to the cold side of the device. Thermionic converters, by contrast are vacuum devices, and inherently insulating (with the heat conducted almost entirely by the working electrons, where it is doing the generation, or parasitic infrared radiation, which can be reflected rater than absorbed at the cold side.) They work very well at temperatures of a couple thousand degrees, a good match to combustion, point-focused solar, and nuclear thermal sources.

Thermionic converters have been the subject to recent improvements, such as graphine electrodes. The power density limitation of space charge has been solved, by using a "control grid" to encourage to charge to move along from the emitter to the collector and magnetic fields to guide it (so it doesn't discharge the control grid and waste the power used to charge it).

Current thermionic technology can convert better than 30% of the available thermal energy to electrical power and achieves power densities in the ballpark of a kilowatt per 100 square cm (i.e. a disk about 4 1/2 inches in diameter). That's a reasonably respectable carnot engine. This makes it very useful for things like topping cycles in steam plants: You run it with the flame against the hot side so it is at the combustion temperature, and the "cold" side at the temperature of the superheated steam for your steam cycle. Rather than wasting the energy of that temperature drop (as you would with a pure steam cycle) you collect about a third of it as electricity.

It also beats the efficiency of currently available solar cell technology (and the 33.4% Shockleyâ"Queisser theoretical limit for single-junction cells), if you don't mind mounting it on a sun-tracker. Not only that, but you can capture the "waste heat" at a useful temperature without substantial impairment to the electrical generation or heat collection, and thus use the same surface area for both generation and solar heating. (Doing this with semiconductor solar cells doesn't work well, because they become far less efficient when running a couple tens of degrees above room temparature.)

Comment Re:Less service? (Score 1) 334

I don't know how the expected lifetime service cost shakes down; but what the dealership cares about is the margins on the service and maintenance they perform; not the absolute cost.

I would suspect that battery swaps, while they involve a very expensive part, would be pretty unexciting for the dealer. Unless the manufacturer is extraordinarily tight-lipped, the price of the battery will become public knowledge; and the procedure for swapping it out(while it might require equipment that makes DIY impractical, depending on where the battery is located and what needs to be lifted) should be rigidly documented and leave little room for variation in how much labor you can bill for.

Somebody has to do the swap, and presumably they won't do it for free; but there is little room either for value-added expertise(as with problems that require diagnostic work) or just plain sleazy invoice padding(as with problems where the customer doesn't know the cost of the parts, or which parts are necessary, or what the expected labor time is); it's a rigidly scripted drop-in replacement of a single module.

Comment Re:Many a young engineer.... (Score 2) 92

... 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:Yeah, I've worked with a few of those (Score 1) 454

So if management stops treating engineers like expendable crap we might be less inclined to spend our working hours pondering how to kill them without getting arrested for it?

Seriously, some of those wasters of precious oxygen are only still alive for the only reason that they're not worth the jail time.

Comment David Edmundson answers your questions (Score 5, Interesting) 525

All of your questions are easily answered by reading the link provided at the top of the article:

Why does the desktop care who's booted it up?

The Init System "We don't care. It doesn't affect us."

logind Allows KDE to provide user-switching features.

Device Management Allows KDE to have access to your mouse and keyboard without root access and without random applications being able to sniff your keystrokes.

Inhibitor Locks Allows KDE to react to notifications like "the system is about to go down" and delay until a condition is met (example: delay a suspend until the lock screen is displayed and all your desktop windows are hidden behind the lock screen).

timedated and Friends Allows KDE to set time and date without root; allows KDE apps to be notified if time and date gets changed. (KDE currently runs a daemon just to watch for time and date changes, and they would like to get rid of this daemon and simplify their code.)

User Units If KDE takes advantage of the "units" in systemd, then when any part of KDE crashes or hangs, systemd will restart the misbehaving part.

that implies they won't work on *BSD at all. Right?

"Projects like [SystemBSD] bring the interfaces we need to BSD and as it gets more stable we should be able to start distributing features."

So really, choice is being taken away clear across the board. Either that or I'm missing something really big which implies systemd is not a strict dependency.

I encourage you to read the whole article and see what big things you are missing.

I don't know about you, but when I read that article I didn't think "Man those KDE guys are idiots, why would they want any of that." It all makes sense to me.

It's easier for me to believe that SystemD has some merit than to believe that all the Debian core developers are idiots, plus all the Ubuntu developers, and now all the KDE developers and for that matter the Gnome developers.

My biggest concerns with systemd are the monoculture of it all, so projects like UselessD and SystemBSD sound great to me. Force the SystemD guys to document and justify everything, and provide alternatives.

Why did the Roman Empire collapse? What is the Latin for office automation?