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Comment Silly conclusions - shorter neural pathways (Score 1) 176

While size would matter, I don't see why metabolic rate should have anything to do with it. It's also funny to hear it described as 'time going slower.'

The nervous system pathways for flies are much shorter. Therefore, flies have lower lag. Go figure.

Just like an L2 cache on a computer processor, since the speed of information travel is pretty well fixed for the selected technology, using shorter path lengths yields faster response times provided the tasks are simple enough to benefit from it. Reflexes in people are like this. http://en.wikipedia.org/wiki/Reflex Detailed thinking has a lot more overhead. And while stimulus-response is more rapid for reflex type behaviors, the speed of thought is the same. (An L2 cache won't change the speed of light.) Using reflex is just a more efficient arrangement for certain types of tasks.

Comment Re:What is it with plastic? (Score 2) 773

The savings happen in the manufacturing process.

Typically for this type of production volume you will heat the material to a liquid state, squeeze it into a mold, let it cool, and then kick it out to make another. It's a lot easier to squeeze and pump plastic into a die, so the manufacturing costs to produce finished plastic products are much lower.

For metals, the process looks like this:

Whereas for plastics, the process looks like this:

Submission + - Microsoft and Google Challenge US Government Gag Orders (informationweek.com)

ace37 writes: Microsoft says it plans to move ahead with a lawsuit filed against the U.S. government in June to affirm the right of businesses to disclose limited information about government demands for data made under the Foreign Intelligence Surveillance Act (FISA).

In separate legal filings, Microsoft and Google challenged the gag order that typically accompanies FISA demands for customer data. The two companies asserted that they have a First Amendment right to publish the total number of FISA requests received and the total number of user accounts covered by such requests.

Submission + - Facebook to include profile photos in its facial recognition database? (sophos.com)

Em Adespoton writes: Facebook has published a summary of the updates it's proposing to make to its Data Use Policy and Statement of Rights and Responsibilities which shows a large volume of rewriting.

Most of the changes are minimal, but one area has caught people's attention — photo tagging.

Facebook has highlighted how it plans to use members' profile pictures as an identification tool to allow their friends to tag them in photos.

NakedSecurity's Lee Munson has more details, including comments from Facebook's chief privacy officer Erin Egan on why this is a "good thing".

Comment Re:1G? (Score 1) 258

Eh, that math is close enough. Between 30 and 35 minutes if you just hold 1G the whole time at both ends. NY to LA is 2,790 miles.

If we assume acceleration at 1G for 15 minutes, then deceleration at 1G for 15 minutes, our average speed is the speed at 7.5 or 22.5 minutes. At 7.5 minutes, that's V_avg = 9.8 m/s^2 * 450 s = 4410 m/s, and V_max is twice that speed. Mach 1 at STP is 331 m/s, for reference.

4410 m/s * (30 min * 60s/min) = 3969 km = 2466 mi.

Add four minutes at the same average speed and we hit LA. Or pull just over 1G. Either way, it's pretty nearly 30 minutes.

Comment Re:Ground effect (Score 3, Informative) 58

I forgot to mention the most important part -- the majority of the flight is done very low:

Power required is shown for rotor height of 60 cm (2 ft) above the ground. The 60-second duration flights will be flown as close to the ground as possible to increase ground effect advantages.


Comment Re:Ground effect (Score 4, Informative) 58

With the speed those rotors are turning, I don't think there'd be much in the way of ground effects generated.

Just an old helicopter mechanic tho, not an aeronautical engineer So I might be completely wrong..

Typically about 1.5 rotor diameters are where it stops helping a traditional helicopeter. In this case, at 10 feet up with a 30 foot diameter, the slow rotor speed notwithstanding it will make a significant contribution. The air below the rotors can't freely move downward until the momentum of the wind dissipates; this energy creates lift.

Ben Berry from Gamera was actually a previous coworker before he went to work on their HPV project.

Source: Aero engineer, rules of thumb there are from asking around at Sikorsky years ago. Also, I don't like how they say this at all, but it at least says the ground effect is significant:

Three years ago, as Staruk and his UMD team began building their first iteration of Gamera, they quickly encountered the boundaries of current aerodynamic understanding. To rise off the ground, human-powered helicopters are helped by a phenomenon called ground effect, in which wings close to the surface of the earth experience a sharp reduction in drag. It's very helpful in getting off the ground but difficult to model. "Ground effect is a very complex phenomenon; there are all sorts of vortices," Chopra says. "You can only validate experimentally. There isn't much theory."


Comment Description words (Score 1) 155

Unlike, say, Finnish, where the Finns will typically just take an English or Swedish, Russian, &c word and spin the pronounciation to expand their tongue, the Navajo typically create a new compound word that is a description. This is a rather laborious way to rapidly expand a language. A fun example is the Navajo word for "Dog," ééch'í. That literally means "one who eats poop."

Outsiders like most of us can't cause a traditional language to adapt. The burden is on the speakers. In this case, teaching English as a second language (or French or w/e) is a better solution than trying to quickly and drastically expand a language spoken by so few, then figuring out how to translate every time we need to interact.

The Navajo language was only written in the 20th century. Even if we were able to fully expand Navajo to cover conversation with the same breadth and depth of a multicultural language like English/French/etc., and if further we could somehow teach all of the new words to all of the Navajo-speaking Indians right away, then if they don't have for instance any Navajo cabinetmakers who use the new words for cabinetry tools all the time, all those related words would die in a few years. After a decade or two, we'd be left very nearly where we are now.

Language is a living thing, and words that are long unspoken die. It's a pity, but at a certain point, a nearly dead language becomes a cultural relic, as Navajo is today. Preservation of this as a cultural relic is great, but not easy.

Comment Re:Awesome (Score 2) 140

Do you feel the Microsoft Windows Phone licensing model fits this royalty and licensing model you suggest? Many on Slashdot claimed that the licensing approach they deployed was simply extortion to increase the cost of Android to match Windows Phone.

Fairly pricing your royalty and licensing costs for patents have always been an issue, a la Xerox. Of course, that's sort of exactly what the patent system is designed to enable - it grants a temporary monopoly to a business in exchange for public disclosure of a proprietary innovation.

It all really falls apart when the patented "innovations" are obvious to the majority of skilled designers or engineers.

Comment Just misleading accounting / journalism (Score 1) 340

I don't think they're claiming to violate the laws of thermodynamics; it appears they're just using an inappropriate reference value. Based on the rest of the quote, it looks like they are using the 100% efficiency energy output from burning the biomass as the reference and comparing it to the net energy output using this method. I base that on the context from the rest of the quote:

...Even more appealing, this reaction occurs at low temperatures, generating hydrogen energy that is greater than the chemical energy stored in xylose and the polyphosphate. This results in an energy efficiency of more than 100 percent — a net energy gain. That means that low-temperature waste heat can be used to produce high-quality chemical energy hydrogen for the first time. Other processes that convert sugar into biofuels such as ethanol and butanol always have energy efficiencies of less than 100 percent, resulting in an energy penalty.

Comment Re:Good. (Score 3, Insightful) 761

Completely agree. It's an issue, so if they want to make a point, put the guy in jail for a week or two. More than a day but less than a month.

A 30 month sentence is not appropriate for being a douchebag. This is essentially just making an example of the guy and is unjust--the punishment doesn't fit the crime at all. Because of that, I hope this knucklehead appeals and gets off scot free.

Comment Re:Enter the new airship age ... (Score 1) 198

So how strong is the aerogel? How big a bag can we make and have it support atmospheric pressure on the other side? That will really determine the lift efficiency.

As an ultralight foam, it has strength, but very little. You can order aerogel samples online - I did a year or two ago (glass aerogel, not graphene). It's extremely brittle and has almost no impact strength, but it has sufficient strength to be made useful. You could conceivably do what you suggest and create a bag of it, then isolate it from the exterior surface or any surface that might see impact damage. It could certainly be made to work if you had enough time, money, and talented minds.

The problem is, if airships using He aren't cost-effective today, it's looks unlikely that making airships of graphene aerogel (or any other type of aerogel) will be cost effective for many decades. As a scientific curiosity, aerogel does have a higher-than-typical chance of benefiting from a game-changing technological development, so hopefully that will be proven wrong.

Comment Poor that pay (Score 1) 416

It's the poor who will pay. I don't mean the middle class, I mean the 1 billion+ people who live on less than $1 a day. They will starve in greater numbers and die in greater numbers - they can't move, or "buy less ski equipment". I get that you don't care about that, but I hope that as a society we can bring ourselves to give a shit.

While I completely agree with your sentiment and emotional judgment, I slightly disagree with the point you make here. If I as a member of society want to reach out to the world's impoverished, I'm not going to effectively demonstrate my altruism by buying a hybrid or pushing for 'better' emissions laws. I'm going to do it by spending some of my resources supporting my favorites of the many community organizations, charities, government organizations, individual efforts, etc. who are striving to implement long term solutions to the problems of impoverished nations.

Those living on $1 a day don't give a damn about my CO2 emissions. They'll be dead before that really bites them. They want food and shelter today. The upcoming generations suffering the same fate is an issue, but with little effort, we can fix many of the the root causes over the coming decades, and it has almost nothing to do with our emissions. We should be developing and executing plans at many levels to build up basic infrastructure and establish the rule of law, and we should be looking at areas with great need and areas where we have a great ability to bring about meaningful change. Hopefully then the great grandchildren of those people can eventually join ours in a world community trying to resolve more of the global warming mess. And if not, they can all compete to buy prime Canadian and Siberian coastal real estate. Either way, nobody is starving, and our world will be much better off than if we continue to sit together arguing about emissions and giving the impoverished our pity while we leave them alone to figure out their problems.

Today, I think one of the biggest battles is to change the views of the citizens of our developed societies. I hope by the end of my lifetime we've started to believe we have a great responsibility to uplift the impoverished fellow citizens of this planet we all share.

Comment Simple matter of self-interest? (Score 4, Insightful) 123

Despite the fact that this is Slashdot, I'm surprised at the number of upvoted anti-MS epithets. I don't see how this needs to have anything to do with the merits of the OS itself when a CEO with an MBA and a Blackberry could easily come to this conclusion on a purely business case.

Neutral phone hardware developers would perceive a small market that requires investment to pursue. Most likely, LG's expected market penetration isn't large enough to justify the investment. And for the cynics, LG could also assume that, to loosely paraphrase Animal Farm, all carriers are equal to MS, but Nokia is 'more equal,' barring antitrust suits. This creates an additional small interest in starving WP of revenue to keep Nokia out of the ring.

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