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Making Microelectronics Out of Nanodiamond

uid7306m Don't get too excited (80 comments)

I did research on this stuff back in the 1990s. Made the films, did the vacuum chambers, had the world record for emission efficiency for a while. While it may have some niche applications, the basic problem is that it is *not* a low-voltage technology. Modern chips operate on 1.5 V or so; Diamond devices will be more like 5V. So ultra-low power? Nope. They say that the devices are more efficient because the electrons don't bump their way through the silicon crystal lattice. While that's true enough, it doesn't actually make a big difference. Why? Because the electrons very much will dump all their energy when they leave the vacuum and hit the anode.

Ultra-high speed? Again, while vacuum is nice in that it doesn't slow down the electrons, that turns out not to be a big effect. The most important factor in speed is the size of the device, and there is certainly no reason to believe that these vacuum tubes will be smaller than transistors, if built with the same lithography tools. I may be wrong, but I have good reasons to believe that they will be harder to make small.

High temperature? Radiation resistance? Maybe, but that turns out to be a complex question. These devices aren't just diamond and vacuum. They involve insulating layers, too, and those insulators may be affected my high temperatures or radiation. Essentially, a device is as robust as its weakest link, so until you can make the entire device out of truly robust materials, you won't gain too much.

So, it's nice work. I know how hard it is to do this stuff. And, it might be useful eventually. But it won't revolutionize technology any time soon. And, those guys ought to realize that, if they would let themselves. Research lives off publicity these days, because it is being forced to become more and more of a competition between groups. The trouble is, when competition enters and your salary depends on the claims you can make, truth tends to be (shall we say) over-inflated.

That darn free market ideology messes up science. I like it as much as anything for people who make spoons or telephones. But science isn't making spoons. If you get a bad spoon, you'll know it, but if you read an exaggerated research paper, how can you tell, other than by doing the research again? And, that's just not efficient: doing it wrong and then doing it again isn't nearly as good as doing it right the first time.

Oh well. Enough ranting.

more than 3 years ago

Harnessing Interference For Faster Wireless Data

uid7306m Re:Interference from other sources is a killer (91 comments)

Nope. Sorry. You're wrong. Electromagnetic waves add very nicely, so that your signal remains there, even if many other signals are simultaneously being transmitted.

The overall idea is fine, in principle. As other people have said, it is 802.11n beam-forming on steroids. If you had 1000 transmitters, and if you could know the exact time delay and attenuation from each of those transmitters to your cell phone, then (indeed) you could make them all add together precisely where your cell phone is. Elsewhere, they would (on average, mostly) cancel out. As advertised, you would (indeed) get a substantial improvement.

But not a *huge* improvement. With N=1000 transmitters, the signal at your cell phone would be (e.g.) 1000. Elsewhere, the signal would be (in the same units) typically sqrt(N) or about 30. That value of 30 is the noise level for eveyone else, and their transmissions give a similar noise level to you. So, 1000 transmitters gives you a signal-to-noise ratio of 30 times better than one transmitter.[*]

[* ...actially, if you're really gonzo, you can adjust all the transmitters to make their signals cancel out exactly, at everyone else's cell phones, so long as you have more transmitters than cell phones. In principle. But I don't think anyone is seriously proposing that...]

Now, you plug that into Shannon's equation, where the data rate is B*log((S+N)/S), B is the bandwidth, and S is the signal and N is the noise. If you start with S=N=1 which is not too far off for a normal system, and change it to S=1000, N=30, you find that the data rate increases by a factor of 5. Which is good and impressive.

But the problem is that it is very hard to know the attenuation and time delay precisely.

So, anyway, it's not a bad idea, but it's hardly new. It's also not easy to implement, and even if you implement it, you won't get factors of 1000 improvement.

more than 3 years ago

House Websites Jammed After Obama Debt Speech

uid7306m Re:We're a sinking ship (1042 comments)

Yeah, except that lowering taxes doesn't seem to grow the economy. Certainly not enough to make up for the lowered rate. Too bad. It's all sensible except for that point.

Anyway, the top 20% pays 86% of the taxes, maybe, but don't they own an equally large (or larger) share of the wealth and income?

When I was a kid, in the 1960s, tax rates were way over 50%. Tax rates in England peaked at 90%. While 90% marginal tax rates will certainly hurt your economy, it's not at all clear than 30%, 40%, 50% rates will do much damage. If we can manage to spend some of that on useful infrastructure things, it may even be good in the long run. Just think! We could have a well-educated, healthy workforce, streets and networks that work, et cetera.

more than 3 years ago

Google Grabbed Locations of Phones, PCs

uid7306m Re:Not sloppy coding, surely? (230 comments)

Well, find out for us instead of just talking. Write the code both ways and show it.

Anyone with *any* experience of software knows that you cannot tell if something is "easy" or not until you've done it (or done something that's very similar).

more than 3 years ago

Hotspot Found On Moon's Far Side

uid7306m Neat! (96 comments)

That's all I can say.

more than 3 years ago

NJ Judge Rules GPS Tracking of Spouse Legal

uid7306m Re:A simple solution... (241 comments)

Could be a boring life. I suppose you get tired of them rapidly because you don't really know them all that well.

Sounds like you're living your life in fear of losing half your property.... Weird. Property is just stuff. Plastic, mostly. Soon to be junk, mostly. Stuff that requires you to buy closets. Stuff just gets in the way, mostly.

One of my most enlightening experiences was when I moved to England and found out how small the typical English house was, compared to my American house. I ended up throwing out/selling half of everything I owned. And, guess what? I didn't actually need any of it. (Of course, I would have regretted losing some of the *other* half...)

more than 3 years ago

NJ Judge Rules GPS Tracking of Spouse Legal

uid7306m Re:A simple solution... (241 comments)

That's a very self-centered view. Not evil, but just thinking about yourself.

Some of us like the knowledge that there is someone permanent around who is willing to help. Someone to talk to. Someone who gives a shit. You can't buy that last two. You can buy a helper, you can buy sex, but you can only buy people who pretend to care about you or about what you say. If they are in it for the money, they don't care about you. Rather, they only care about your money.

And, some of us are willing to actually pay attention to someone and to give a shit about them, in exchange. You can call it love, you can call it partnership, you can call it whatever you want.

more than 3 years ago

After 7 Years, MyDoom Worm Is Still Spreading

uid7306m Re:Windows is nothing if not backward-compatible (133 comments)

Absolutely. By blocking anything potentially dangerous, you end up with a safe organisation that isn't able to function well.
Obviously, the I.T. guys see their own pain. But, the pain that excess security causes is widely distributed across space and time, and no one counts it all.

So, in this case, yeah, a virus is bad news. But, the question is, is a virus more lost productivity than 1000 people who are unable to send zip files?

more than 3 years ago

Ask Slashdot: How To Encourage Better Research Software?

uid7306m Re:Here is how (104 comments)

Yeah, right. Scientific software is not at all like a word processor. In a word processor, you can tell immediately if it is behaving wrong: you know what it is supposed to do. But in some scientific computation, it's just the reverse. It tells you that the answer is 3.184, and it is not immediately obvious whether the answer is right or wrong. That's the difference.

"To weed out the crap" as you put it, you need to understand the computation in detail, design some test cases that are relevant to your own problem, test it, and think about the approximations that are being made. This can take weeks, months, or even years.

And, then after you've decided if it works well enough for *your* research problem, the next guy is probably going to run it on a slightly different problem. Some of those questions will raise their ugly heads again. Are those approximations still good enough? Do I need different test cases?

Basically, the difference is that with commercial software, you write it once and people run it a billion times. With research software, you write it once, and run it once. Maybe, you'll use it again, once, or maybe not. Maybe three other guys (girls) will use it too. But that's about it. Once the program works, your research question is answered, and that might be the end of it.

more than 3 years ago

Do Violent Games Hinder Development of Empathy?

uid7306m Re:The sponsor is always right (343 comments)

Oh, so young to be so cynical. The interesting thing about real science is that *sometimes* the answers are unexpected/unwanted. The other interesting thing about real science is that you actually find some scientists who care more about the real answers than the answers they were "supposed" to get. The third interesting thing is that there are nonscientists and funding agencies who actually care what the real answer is.

So, sometimes, cynicism fails. Don't be corrosive.

more than 3 years ago

Encrypted VoIP Meets Traffic Analysis

uid7306m Re:useless, and easy countermeasures (98 comments)

Exactly. The phrases used are fairly long, for instance: "Laugh, dance, and sing if fortune smiles upon you." In the TIMIT corpus, there are 122 of them. In the English language, there are hmm, lots of sentences of that length. There are about 1000 different syllables in English, and I count 11 syllables in that sentence. Thus, there are some fraction of 10^33 sentences of that length.

So, if you tried this on English, one of two things would happen. If you used that recognizer without any modification, then it would sit there silently until you said one of the sentences in TIMIT, like "She had your dark suit in greasy wash water all year." And, it would be a *long* wait.

Or, you could change the recognizer so it could recognize more than 122 possible sentences. In that case, the error rate would go way up.

more than 3 years ago

61.9% of Undergraduates Cybercheat

uid7306m Re:What constitutes cheating? (484 comments)

When considered from the point of learning something, there's a certain grey zone. Looking up an answer can be a way to learn, as long as the idea passes through your brain en route. But it's certainly cheating if it goes from the browser to the word processor and you don't understand what you are copying.

more than 3 years ago

61.9% of Undergraduates Cybercheat

uid7306m Use the brain as a cache (484 comments)

Ya gotta cache in the brain.

Yes, it's true you can become an expert in anything these days. I've done it, going from one research field to another, and I'm expert enough to get paid to do the research. But you still have to know a lot of stuff, because it takes 300 milliseconds to pull a fact up from the ol' grey matter and it takes anywhere from 30 seconds to 30 hours to find it on the internet. If you need the internet to answer basic questions about your area of expertise, you aren't an expert. Or, at least your a verrrrrrrrry sloooooow expert.

more than 3 years ago

Scientists Find Tears Are the Anti-Viagra

uid7306m The level of discourse (207 comments)

Geez, guys. Mental age should be at least 16, mental altitude should be at least a foot above the gutter.

about 4 years ago

Social Security Information Systems Near Collapse

uid7306m Re:Typical IT cognitive distortions... (279 comments)

From http://www.cbpp.org/cms/index.cfm?fa=view&id=1648 :
Simple rate-of-return comparisons such as those Glassman and many other individual-accounts proponents use fail to take into account the costs of continuing to pay for the benefits of current beneficiaries (and the benefits that current workers have accrued) when computing rates of returns for individual accounts, while including these costs in the rate of return computed for Social Security. These costs remain, however, even if Social Security is eliminated for new workers and replaced entirely by individual accounts. As a result, such comparisons are inherently biased. Since the payments to current beneficiaries (and the benefits that current workers have accrued) are not avoided by setting up individual accounts, the returns on individual accounts should not be artificially inflated by excluding the cost of these payments.

In other words, we have the obligation to pay for people who don't have 401ks yet.

Also, 10% earnings is unrealistically optimistic! I just looked up my Vanguard accounts, and over 10 years, 5% is more typical. And, *then*, you have to subtract off inflation. In the real world (vs. one's dreams) one has to settle for about 3% yield over inflation.

So, sorry, parent post. You're all wrong.

about 4 years ago

Groklaw — Don't Go Home, Go Big

uid7306m Re:The lesson is... (230 comments)

Oh, don't exaggerate. Corporations have no soul, but profits are not evil.

You can trust a corporation to do things that people are willing to pay for. Most of those things are useful, though some are ethically dubious.

about 4 years ago

The Luck of the Irish Runs Out

uid7306m Re:A parable on taxing the rich (809 comments)

This is, of course, blatant emotionalism. Taxing someone isn't the same as physically beating them up. But, changing countries is a lot like changing pubs. All of a sudden, there's no one to talk to. People don't move from one country to another very easily.

So, what happens to the tenth man?

Should we say that the tenth man ended his days as a sad drunk, drinking alone at home, because he wouldn't drink with his fellows? Or, is it a triumphal outcome for him? Does he go to another bar and find a better class of friends. Who knows?

more than 4 years ago

Google Warns Irish Government Against Tax Increase

uid7306m Re:Wrong about wrong (542 comments)

Except that it's not a perogative for most private persons to move. You have to fulfil immigration requirements, for one thing. You need to learn a language. You need to drop most of your friends and family. You need to be ready to let your mother die, alone, in a nursing home. All of those things make it impractical for many people to pull up their stakes and go to a different country.

People are not very mobile.

more than 4 years ago

How Cornell Plans To Purge Campus Computers of Personal Data

uid7306m Re:What does "computers of university employees" (164 comments)

Maybe they left it there because they didn't know how you set up the system? Maybe you think they should take the time to understand your system, and perhaps you don't take the time to understand your users?

Maybe it's wasn't a good idea to set up a system that dumps scan data to a publicly accessible hard disk?

more than 4 years ago

How Cornell Plans To Purge Campus Computers of Personal Data

uid7306m Re:What IT staff need to understand (164 comments)

You sound like an IT administrator who has never done research.

* When you run computations that take weeks to complete, reboots *need* to be rare events that are negotiated between IT staff and researchers. Otherwise, productivity goes to zero, and then what's the point of having computers or IT staff?
* When you have terabytes of data, scans can be a major time sink. And false positives? If it eats some of my data by accident, that's big trouble.
* When you've spent a few weeks compiling some odd software and getting 17 libraries to work in concert, the last thing you want is some heavy-handed sysadmin messing with your system. Everyone's big fear is that if you touch the system, you might break it in some subtle way. Subtle problems lead to weeks of debugging or wrong answers, and if you get the wrong answer, what's the point of having computers or IT staff?

The sensible approach is that you have to have a sysadmin who works with the researchers and actually believes that his job is to help do some research. And, sure, the researchers have to make some compromises, too. But research is hard enough to do, even with minimal annoyance from outside.

You need a sysadmin who is willing to say "OK, let's figure out how to minimize the risk" instead of some jobsworth who says "Tough sh**, them's the rules, and I don't much care that the rules were designed for the typical desktop system." In my experience, given good IT staff with the right attitude, most researchers are happy to cooperate. IT staff who cause trouble without providing help will get a different reception.

more than 4 years ago



UK Scientists leave labs to protest expected cuts

uid7306m uid7306m writes  |  more than 4 years ago

uid7306m (830787) writes "The UK government is planning an austerity budget, in the wake of the financial crisis and banking bailouts. This involves a 25% overall cut in the government budget, and the indications are that it will hit UK science and university budgets strongly. In response to this, a campaign has started that has managed to get scientists out of their labs and into the streets. The BBC has a story here.

It's not just about saving jobs: science builds the economy, is the basis for just about all the technical toys you can imagine, medicine, and perhaps one day will even sort your socks or save the ecosystem. So, there are good reasons to keep science funded."

Link to Original Source

Solving UK Libel Tourism?

uid7306m uid7306m writes  |  more than 5 years ago

uid7306m (830787) writes "The UK is known as the world's best place to be libeled. That is, to have someone publish a damaging falsehood about you. That's because you don't have to prove libel: you just prove damage, the defendant to prove that what he/she said was true beyond a reasonable doubt. To an extent, it is guilty until proven innocent, and UK courts have a global reach.

This is a concern to every blogger who wants to express an opinion. Unless you are very careful, what you say may harm the reputation of someone in the UK. And, they can sue you. And, if they win, you are liable for their court costs. (Recall that the UK has a "loser pays" system for legal fees.) In fact, you don't even have to libel someone who lives in the UK, merely someone who has business dealings and a reputation in the UK (e.g. here) or an UK organization like the British Chiropractic Association (e.g. here).

Now, I Am Not A Lawyer, but perhaps there is a solution, at least for people outside the UK who publish electronically. The solution may reside in the Computer Misuse Act 1990 (UK), which makes it illegal to access a computer without authorization. Penalties are strict, including prison time.

Suppose people started putting the following header on their web pages: "Access from the United Kingdom or by United Kingdom residents is not authorized. Violators may be subject to the Computer Misuse Act 1990."


Video to Grandmother

uid7306m uid7306m writes  |  more than 6 years ago

uid7306m writes "We have elderly parents who live a long way off. However, my technological radar tells me that it's possible to set up a 24/7 video link between our kitchen and theirs. It'd be good for our kids and good for the parents, and we can now get pretty cheap nearly unlimited broadband connections at this end (UK).

What's the best way to do it? Has anyone tried it? On the far end, it ought to have, in Dilbert's(TM) immortal words "One big button on it, and we push it for you in the factory.""


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