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Submission + - Nanoscale Device Makes Light Travel Infinitely Fast (sciencemag.org)

sciencehabit writes: Physicists have developed a tiny device in which the index of refraction for visible light is zero—so that within it, visible light travels infinitely fast. The gizmo won't lead to instantaneous communication—the famous speed limit of Albert Einstein's theory of relativity remains in force—but it could have a variety of pretty cool uses, including serving as an element in a type of optical circuitry.

Comment Just a nutcase blogger with a grudge? (Score 1) 130

I have yet to see even one example of plagiarism among the 92 examples given. The blogger seems unable to understand that it is common academic praxis to sum up e.g. a theory from a work. Of course such a summery will bear some resemblance to the original work, otherwise it wouldn't be a summery. But as long as there are good footnotes documenting this, it isn't a problem.

One could in fact argue, that since the blogger doesn't seem to have found even one good clear case of plagiarism, the dissertation comes out strengthened.

Comment Re:Ext4 metadata checksums (Score 1) 277

It is not that I doesn't drool over Btrfs. I also think it is very stable, but if the Fedora committee decided that Ext4 was the default FS for F17 I think it is better for me (who doesn't compile my own kernel any more, but a cheer to those that still do that like you) to wait for at least Fedora 18.

And advanced filesystems are really really hard to get right, I will be really surprised if some corner case bugs doesn't show up when Btrfs is deployed on a large scale. There is also the various support tools to consider, like Btrfsck that wasn't fully production ready last I checked.

But you got a point with the added benefit of data CRC checks and scrubbing, these features are both highly desirable and makes me feel much more confident in changing to a new filesystem since the dreaded "silent data corruption" is what I fear most.

Comment I am impressed (Score 4, Insightful) 62

I have played around with it for 10 minutes and have already found several alternative routes for my new cycling commute route, some even shorter than my current route.
The "Streetview" feature combined with this new cycling route planning feature makes Google maps really awesome.

I think exercising like running is totally boring, but somehow how cycling is different to me, it is just some much fun. Commuting to work is a blast; I arrive fresh, awake, full of energy, and with a smile on my face. Commuting home is nice too; I can unwind stress by going fast, so when I arrive home I am just relaxed. Endorphin rush is probably part of this good feeling, but my blood pressure and rest heart rate have improved a lot since I started cycling again.

Comment Re:Oversimplified article: (Score 5, Insightful) 214

Wegener's idea of continental drift was correct, but he didn't have a good mechanism for how these continents could plow through oceanic crust to move. That takes a massive force, and there wasn't enough energy to do it.

Later it was realized the continents were relatively light and floated atop moving plates. That provided a mechanism where the internal heat engine of the earth could provide enough energy to make them move.

It wasn't just stodginess that kept Wegener's idea from being accepted. It was also real physical objections. Until the 50s/60s and the discovery of seafloor spreading from the patterns of magnetisation in the seabed, the dynamics just didn't work out.

Now, in hindsight, it's "obvious". But it certainly wasn't at the time. The matching of geological features was intriguing, but without a mechanism for the continents moving, it couldn't overcome the objections.

Excellent summary of the usual excuse for why leading geologist snubbed Wegeners theory. But there are several problems in this excuse; first of all, while Wegener didn't have a mechanism for explaining /how/ continental drift worked, neither did his opponents when it came to explain their opposing theories! They had to invent suddenly raising land-bridges that spanned 1000 of kilometres between all the continents to explain away the identical fossil records, land-bridges that appeared and disappeared without any trace or explanation, or without any known mechanism to cause them. The "anti-Wegeners" had even more severe problems than the "continental drifters" when it came to "mechanisms" explaining the data.
Wegeners theory could explain a lot of observed geological and biological data at the same time, while the "anti-Wegeners" had to invent many different theories to explain the same data, many without any explaining mechanisms or any physical evidence like the land-bridge network between all continents, or hot water streams that conveniently appeared when it came to explain why temperate fossils appeared in Arctic regions, or why /identical/ rocks didn't come from the same source. Wegeners idea wasn't armchair speculation, he had lots of hard data from many different sources, data that had baffled scientist before.

Newton didn't have any "mechanism" or explanation on what gravity was or what caused it in his "Principia..."; he only described its effect, yet his work was widely accepted. Darwin didn't have any mechanism explaining why beneficial traits to be inherited by the offspring, since DNA wasn't known, yet his work was widely accepted because it explained the observed data so well.

I think a much better explanation of why continental drift was suppressed with quite some vigour, is Not-Invented-Here syndrome, group-think, and conservative and stagnant leading scientists suppressing new theories, rather than any sensible scientific process.

Comment We did it a decade ago (Score 1) 257

A short brain dump;
Rule number One: Everything should be done in such a way, that it requires as little works as possible for the volunteers.

Let everything be hosted at a provider; email isn't a core service the same way it used to be since people use gmail, sms etc. Same with web servers. Only provide "pure" Internet access. Buy outside knowledge if necessary. We still run our own email servers and firewall, but that is because we are Linux freaks willing to invest the necessary time in such projects. It certainly helped the careerer of some of the volunteers that we ran things like DNS, email, Squid, Apache, firewall etc.

Install LAN cables. Install Coax for TV and radio if needed, set-up a separate TV committee if there is interest. Keep the cables as a separate investment. Not everybody wants (your) internet access since eg. their employer pays their present internet access, but every condo should be wired regardless if possible. Sell it as an investment that increase the property value.
Make sure the cable installer knows what they are doing. Buy outside help if needed.

For historic reasons our network is a NAT'ted LAN. Not sure it makes sense any more to be able to directly share resources between condos since eg. running you own game server is on its way out, so it may provide less hassle to simply isolate every LAN access. That also helps against some LAN scanning malware. As a minimum run intelligent switches that can firewall rogue DNS servers etc.

Have a charter or similar, that stipulate what can be done and can't be done with the network; IMHO, you should firewall the internet access pretty strict; don't allow people to host their own email or web servers, since eg. spambots spewing out spam mails from your LAN can cause all kinds of trouble for you (see rule number one).

Internet access is now considered an important utility; so spend some time on service monitoring; eg. if switch 4 is down, who should be informed, who should they call. Make sure the provider has a detailed page on service status, and they inform you when there is maintenance downtime.

After the first hurdles, things will settle down so the committee will get a more reasonable work load. The bonus of all the work is that we have had high speed, (low latency and fat pipes) Internet access for a very low price for more than a decade. It is also a good selling point that the condo have 100 mbit Internet access for $10 a month.

Comment Re:Plagiarism and Attribution (Score 5, Insightful) 166

Being hard is no excuse for not doing it. .

Of course not.

Keeping track of your sources is not a huge task, since the information most often is available right in front of you when you're reading someones work already.

I humbly suggest you are entirely wrong. Even simple manual copying of information leads to errors. Not even double or triple checking will find them all. The errors may be small, but may be significant like writing down a wrong page number. Now imagine 350 pages of text with 1200 foot notes derived from a text corpus of 100 major works ( 30.000 pages) produced over 3 years with some chapters having more than 10 re-writes or revisions. Not counting all the notes and foot notes that never made it into the dissertation, but was produced and needed tracking. You are simply bound to have errors; a simple move of a text section may delete a crucial foot note or place the right foot note at a wrong place. Now imagine doing all this tracking without any computer at all, and only using pen and paper (index cards and notebooks), and type it using a typewriter like the accused did in 1980.

Errors and errata are facts of life, even with the most meticulously produced work, and likewise it is a major challenge and hard work to ensure that the sources in a dissertation are as correct as possible. You simply have to reread and check them all when finished. Not easy at all.

Comment Re:It's plagiarism (Score 1) 166

>Starting at page 7 is where it gets good...and definitely not explainable.

That isn't good example of plagiarism: She gives full sources for the content including specific page numbers in her foot note. Her (anonymous?) accuser can't find any fault in that, but claims that it is plagiarism anyway. Presumably because her accuser doesn't understand what paraphrasing is, or won't accept it as a useful academic tool.
Her accuser claims that this text section /may/ be misinterpreted because of subtle wordings may suggest that not everything in the section is paraphrasing, but her own analysis (of Freud). But again, that is a misunderstanding of paraphrasing. Paraphrasing is a dynamic interpretation of the text content, not just a summery.

Is the section a page 7 too long? Who sets such standards anyway, and where are such rules written down? Is it OK to accuse somebody with plagiarism using standards that few academics would agree on? Should she have broken it up using direct citations. Perhaps, but perhaps not. One can discuss such matter, but accusing one of the serious offence of plagiarism even though they give full sources, is taking things too far.

Comment Doesn't seem like anything serious to me (Score 4, Insightful) 166

Remember that this was written in 1980 probably using at typewriter handwritten notes. It was an absolute nightmare in those days to keep track of sources with small paper cards or notebooks (notebook as in paper notebook).

Errors in major academic works when it came to sources was probably more common in those days, simply because of manual errors in handling stacks of paper-notes. As a rule you will also find far fewer foot-notes in works before electronic word-processing became common, because the workload associated with the footnotes was so high. It was much more acceptable to give general source notes for a chapter instead of placing a foot-note after each paragraph.

I haven't looked at all the claims of plagiarism, but those I have seen seems very minor, like she could have quoted a source from page 14 instead of page 15. Most of claims seems very vague or downright wrong, like claiming 1-2 citations per paragraph is plagiarism when paraphrasing. That is simply absurd.

I haven't seen even one example of substantial plagiarism in the dissertation, in fact, looking at the very few accusations they call "exceptional" all I see is errors likely to be caused by simple mistakes, or outright absurd claims because her accuser doesn't seem to know that paraphrasing with full sources given, is an acceptable and useful academic tool. It is, and especially was, acceptable to paraphrase eg. an academic theory by stating the source used once, instead of after each and every paragraph.

I don't see any pattern of cheating. Her foot-notes are plentiful, she seems to have both read and understood the cited works, the paragraphs allegedly quoted without sources seems more like trivial error than cheating because they seem to contain banal information, not her conclusions. Most of the rest of the accusations seems to bickering about citation standards. Of course, one can discuss when a paragraph should be a direct citation or how much word changing is necessary to call it a paraphrase, but as long as full sources are given for that paragraph (which she seems to do) so that no one can be in doubt where the informations stems from, it is way over the top to bring forth accusations of plagiarism.
There is simply no comparison to former defence minister "Guttenberg"'s wholesale copy-paste cheating (I doubt he even wrote a single word of it, he probably paid a hack to do it for him).

Comment It comes in waves (Score 4, Interesting) 470

There have been several dips in typographic quality over the years, usually when the book industry transitions to a new technology or way of working. Going from Linotype machines to computer typesetting lead to some serious dips in typographic quality for a while. The dip was even more severe when printing was outsourced and most typographers was fired and replaced with layouters and designers. The desktop publishing (DTP) horrors from the late 1980's and 1990 also springs to mind. Usually it wasn't the new technology that was to blame, but that typographic knowledge got lost in the transition to the new technology because of cost cutting measures. The new technologies promised productivity improvements and lower cost through reduction in the workforce, but when the workforce is sacked, their knowledge disappear too.

So it is no surprise that e-books etc. will introduce horrible sloppy typography with no sense of line length versus font size, weird line and word spacing, no knowledge of kerning, no reasoning behind the font used, or matching between text and font.

But over time decent publishing houses will ensure at least some basic standard of typography for their e-books. There will probably not be a return to the high typographic standards of the 1950's early 1960's, but the default quality will be good and unobtrusive enough that it won't disturb the readers. However, the next group of knowledge workers in the firing line are the editors; when they are gone or reduced to merely salespeople, the text qualities of the books and e-books will drop to new low standards.

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Regards

Comment Re:The important part is missing from the summary (Score 2, Interesting) 173

Can't let lack of evidence interfere with how the French feel about themselves. They're still pissed off from Lance Armstrong.

The French media just loved Lance Armstrong, as anybody who actually knows anything about the subject can attest. But of course when it turned out that he was just a cheating doper, some journalists began to write critical articles about him and the entire doping circus he represented.

Lance Armstrong is a cheating doper, no doubt about that; he has simply failed too many doping tests that anybody can deny that. But for technical reasons he can't get a doping sentence because retro-testing can't be used as evidence.

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Regards

Comment Re:The important part is missing from the summary (Score 5, Informative) 173

"Judges said that although no evidence directly linked Messrs. Landis and Baker to the hacking of the antidoping lab, both men benefited from the illegal intrusion."
So, basically, anyone who benefits from a crime is somehow culpable whether or not they actually had anything to do with it.
Gotta love that French "justice" system...

So some clueless blogger totally misrepresent the case and the submitter gives it a flat out wrong headline.

Landis, a known lying doper and cheater, hasn't been convicted for hacking, but for being in possession of stolen documents. Landis, when he was still lying about his doping, was showing these documents to everyone interested, claiming that they showed his innocence, so there is no arguments about him being in possession of these documents.

So Landis escaped a hacking charge and mere got a sentence for being in possession of stolen documents. I am sure that any US citizen publicly showing medical lab records stolen in an hacking accident, would get into trouble with US laws, and rightly so.

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Regards

Science

Submission + - The Secret of Speedy Sharks (sciencemag.org)

sciencehabit writes: Researchers have discovered what makes the shark almost impossible to outswim. By using an engineering imaging technique, researchers have discovered that as a shark’s tail swings from side to side, it creates twice as many jets of water as other fishes’ tails, smoothing out the thrust and likely making swimming more efficient. Sharks do this by stiffening the tail midswing, a strategy that might one day be applied to underwater vehicles to improve their performance.

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