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Submission + - Supposedly GPL-Compliant FAT32 (design-reuse.com) 1

walterbyrd writes: Tuxera Inc., announced the release of a complete, GPL-compliant FAT32 replacement package for Android and Linux. But, I think the code is closed source and proprietary. Also, since the FAT file system is patent encumbered, I don't know if being GPL matters.

Comment Re:dBm vs dB (Score 1) 253

Writing "3dB" is conceptually *exactly* the same as writing "200%".

I just checked the Wikipedia article, and it is totally correct, and agrees 100% with what I stated, as does every physics text that I've ever seen. The definition is what it is, and your assertion that "3dB" is exactly the same as "200%" is simply incorrect.

I don't want to repeat myself or belabor the point, but 3dB represents a 2:1 ratio of power, and a 1.41:1 ratio of voltage. This follows simply and irrefutably from the laws of physics at work, and the underlying mathematical relationship of the quantities being measured, be they field quantities or power quantities.

Remember the basic definitions of the quantities, which is that power is proportional to voltage^2, so it is mathematically impossible for them to change together by the same ratio.

When power changes 2:1, or expressed in dB, 10 * log(2) = 3dB,

Then voltage changes 1.41:1, or expressed in dB, 20 * log(1.41) = 3dB.

I hope that you can see now that your mistaken idea that "3dB==2:1 or 200%" for both voltage and power is impossible, because power is proportional to voltage^2, it is mathematically impossible for them to both vary by 2:1 at the same time.

Comment Re:dBm vs dB (Score 1) 253

(Just for posterity, a factor of 2 == 3dB *always*.)

That last point that you made for posterity is not correct, because the definition of dB relates to power ratios, and a 2:1 ratio of power is 3dB, whereas a 2:1 ratio of voltage results in a 4:1 ratio of power and 6dB of change.

So, a factor of 2 is only 3dB when measuring power, because for power dB is defined as: dB = 10 * log(P1/P0),

and 10 * log(2) = 3

But when measuring voltage, a factor of 2 is 6dB, because for voltage ratios, dB is defined as: dB = 20 * log(V1/V0),

and 20 * log(2) = 6

Comment Re:Ordering and Convergence (Score 1) 981

"I have several pieces of fruit, one of which is a banana grown in Ecuador."

It may well be that the second piece of fruit was also grown in Ecuador, just like the first one was, but I simply don't know, so I don't make any statement about its country of origin, nor do I ask you to make any assumption or draw any inference about its country of origin. Therefore, this statement isn't deliberately misleading, because I don't know the country of origin of the second piece of fruit, as it doesn't have a country of origin sticker on it. My statement is totally true and complete to the best of my knowledge, and does not deliberately withold any information.

The way I see it, the fact that I stated that the country of origin of the first piece of fruit is Ecuador does not imply or require that the second piece of fruit is or is not from Ecuador also.

The way I read and analyze the sentence is that it is conveying complete information about just one piece of fruit, and no information at all about the other piece of fruit. I don't think that it's correct to assume any facts or restrictions not explicitly stated.

Likewise, in the original problem, "I have two children, one of whom is a boy born on Tuesday. What is the probability that the other is also a boy?"

The parent may not know what day of the week their other child was born on, for many reasons, such as separation due to war from the pregnant mother before the child was born. The father may have escaped from the conflict with one child, and only know from witnesses that his pregnant wife was captured and gave birth to a child while in a prison camp. The child born in prison may have been born on a Tuesday too, but the father doesn't know, and doesn't say. So his statement is totally true and complete to the best of his knowledge. But we can't assume that his statement says anything at all about the day of birth of the second child, nor use it in our calculation of the probability that he or she is a boy.

Comment Re:Ordering and Convergence (Score 1) 981

You offer the analogy:

I have several pieces of fruit and one of them is a banana

But the statement in the puzzle is: "I have two children, one of whom is a boy born on a Tuesday

Your example sentence is not analagous to the original problem, because the original statement provides two facts about one of the children, whereas your sentence provides only one fact about one of the pieces of fruit, therefore your argument is flawed.

The correct analogy is: "I have several pieces of fruit, one of which is a banana grown in Ecuador."

It is obvious that this statement about one of the pieces of fruit does not make any statements about the nature of the other piece of fruit, and certainly does not preclude the possiblility that the second piece of fruit is also a banana. For example, the second piece of fruit could very easily be a banana grown in Honduras, and nobody would consider the statement about the first piece of fruit to be a lie.

Submission + - New Air Conditioner Process cuts energy use 50-90% (nrel.gov) 2

necro81 writes: The U.S. National Renewable Energy Laboratory has announced that it has developed a new method for air conditioning that reduces energy use by 50-90%. The DEVap system cools air using evaporative cooling, which is not new, but combines the process with a liquid dessicant for pulling the water vapor out of the cooled air stream. The liquid dessicant, a very strong aqueous solution of lithium chloride or sodium chloride, is separated from the air stream by a permeable hydrophobic membrane. Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas. The dessicants are, compared to typical refrigerants like HCFCs, relatively safe for the environment.
Science

Submission + - Why Being Wrong Makes Humans So Smart 1

Hugh Pickens writes: "Kathryn Schulz writes in the Boston Globe that the more scientists understand about cognitive functioning, the more it becomes clear that our capacity to make mistakes is utterly inextricable from what makes the human brain so swift, adaptable, and intelligent and that rather than treating errors like the bedbugs of the intellect — an appalling and embarrassing nuisance we try to pretend out of existence, we need to recognize that human fallibility is part and parcel of human brilliance. Neuroscientists increasingly think that inductive reasoning undergirds virtually all of human cognition. Humans use inductive reasoning to learn language, organize the world into meaningful categories, and grasp the relationship between cause and effect in the physical, biological, and psychological realms and thanks to inductive reasoning, we are able to form nearly instantaneous beliefs and take action accordingly. But our use of inductive reasoning comes with a price. "The distinctive thing about inductive reasoning is that it generates conclusions that aren’t necessarily true. They are, instead, probabilistically true — which means they are possibly false," writes Schulz. "Because we reason inductively, we will sometimes get things wrong." Schulz recommends that we respond to the mistakes (or putative mistakes) of those around us with empathy and generosity and demand that our business and political leaders acknowledge and redress their errors rather than ignoring or denying them. "Once we recognize that we do not err out of laziness, stupidity, or evil intent, we can liberate ourselves from the impossible burden of trying to be permanently right. We can take seriously the proposition that we could be in error, without deeming ourselves idiotic or unworthy.""
Google

Submission + - Britain's BPI goes after Google -- with US DMCA ! (p2pnet.net) 1

An anonymous reader writes: The BPI, the RIAA's UK counterpart, has gone up against the Holiest of Holies, American online advertising conglomerate Google, says Chilling Effects. The BPI contributed to the British government's Digital Ecomy bill, complete with its ACTA Three Strikes and you're Off The Net element, with hardly a murmur from the UK lamescream media. Now Chilling Effects quotes a missive directed at Gargle by the BPI. It states, in part, "We have identified the following links that are available via Google's search engine, and request the following links be removed as soon as possible as they directly link to sound recordings owned by our members ... " And what's even more interesting is: this British 'trade' outfity is using the American DMCA to attack Google. Can it do that?

Submission + - Man Accused of AT&T Breach Arrested on Drug Ch (theregister.co.uk)

ActionDesignStudios writes: Andrew Auernheimer, the man accused of the recent data breach related to AT&T iPad user data was arrested on Tuesday. The FBI executed a search warrant on Auernheimer's home and allegedly found cocaine, ecstasy and LSD. He faces four felony charges of possession of a controlled substance and one misdemeanor possession charge.

Submission + - iPad customers forced to buy unnecessary add-ons (smh.com.au) 1

CuteSteveJobs writes: Australian iPad buyers have been forced to buy all manner of unnecessary add-ons including screen protectors, docking stations, covers, chargers and extended warranties due to a reported Official Apple policy. Shoppers reported sales assistants said it was “company policy” or “Apple policy” to sell the devices only with accessories, or not at all. A store manager for Authorised Apple Reseller JB Hi-Fi said it was “a bad policy but it was Apple’s policy and they couldn’t sell one without it”. Other customers were told they must "buy a Telstra SIM because the iPad is locked to Telstra", even though it wasn't. The Australian Consumer and Competition Commission and Consumer affairs are investigating the complaints.

What's the point of having Authorized Apple Resellers in this environment? Is it Official Apple policy? Don't look for any help from Apple; An Apple spokeswoman said "she could not comment on company policy", but did offer "consumers could buy iPads directly from us" without any add-ons.

Power

Submission + - From defibrillator batteries to a green revolution (buffalo.edu)

An anonymous reader writes: This month is the 50th anniversary of the first US cardiac pacemaker implantation in a patient (in Buffalo NY at the VA Hospital). The company that made the batteries for the pacemaker, Greatbatch Inc., also Buffalo-based, later went on to hire Esther Takeuchi, who in turn made the cardiac defibrillator possible by developing its tiny but powerful battery.

Now, Esther Takeuchi is seeking a green breakthrough. As a SUNY Distinguished Professor at the University at Buffalo, (btw, she has more patents than any other woman in the US and is a recent winner of the National Medal for Technology and Innovation) she is applying her expertise in battery breakthroughs to environmental technologies like electric cars and wind turbines.

UB's story and video about her (link is in story) are here: http://www.buffalo.edu/news/11424

Censorship

Submission + - Turkey has imposed an indefinite ban on Google

oxide7 writes: Turkey’s Telecommunications Presidency said it has banned access to many of Google IP addresses without assigning clear reasons. The statement did not confirm if the ban is temporary or permanent. Google’s translation and document sharing sites have also been banned indefinitely along with YouTube and Facebook in the country. Other services such as AppEngine, FeedBurner, Analytics etc have also been reportedly banned.

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Quantum Mechanics is a lovely introduction to Hilbert Spaces! -- Overheard at last year's Archimedeans' Garden Party

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