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Comment Re:Capable of Supporting 1000 times its own mass? (Score 1) 57

From deep within the article:

Tuning the trigger temperature is only one part of the story. We also engineered these materials to store large amount[s] of elastic energy, enabling them to perform more mechanical work during their shape recovery,

The capability to lift 1,000 times its own mass means that a device constructed from 1/28th ounce (about the weight of a typical paper clip), could lift a one-liter bottle of water.

Even the article uses "support" many times, which does relate to stress (measured in N or lbs in the US). However, the scientists involved were talking about lifting, i.e. mechanical work, which is measured in N.m (or lbs.ft for Americans). So there is another dimension that you need to multiply in and you will find that the units do in fact match up. Since this distance is not specified in the article, it's still quantitatively meaningless, since for example an enormous pneumatic piston, could in theory lift a M1 tank a fraction of a millimeter when sneezed into, but by dimensional analysis it still makes sense.

Comment Re: make it user-selectable (Score 4, Insightful) 235

What you are taught when you learn how to drive is "always brake, never swerve". Which also happens to be exactly what a self-driving car would and should do in an emergency situation.

Reformulated as a trolley problem, this is: do not pull the lever.

Why? Because swerving will almost always put the car in more danger for itself and others, since it may cause the car to spin, or approach cars in incoming lanes or pedestrians on the footpath, or any number of bad things.

Since, by law, other cars must maintain a safe distance behind you, slamming on your brakes is always a safe response to an obstruction. Any other response, such as changing lanes, should be considered if it is safe or not. If it is unsafe, then you shouldn't do it, things like "busses of schoolchildren" is completely outside the parameters of the problem.

This whole self driving car issue took a wrong turn the day that someone had decided that they had the moral imperative to break the law in order to prevent crashes. You do not have that imperative yourself, you have the imperative to follow the law in order to prevent crashes. The reason that two drivers can pass each other at enormous speeds without prior communication is that the law forces them into their lanes. The law is the protocol that all drivers follow to interact, since they are unable to talk to each other and as soon as you break it, you expose yourself and others to untold danger. If the law says "don't leave your lane" and best driving practices says "don't swerve", then you don't swerve.

Comment Re: I must have been sick that day. (Score 1) 34

AFAIK, on a tidally locked body, a sidereal day and a year take the same time. You can pick whichever you wish, depending on how long you wish to sound like. You can just call it a "month" though, since cycle of the phases of the earth correspond to those of the moon (new earth corresponds to full moon, full earth with new moon) and do away with ambiguity.

To veer off topic, something that ticked me off with the Martian is that nobody reminded how long a Martian sol lasts, but they were used for time periods even on earth and in space, meaning I had no idea of elapsed time.

Comment Re:Need to protect it well. (Score 5, Funny) 129

According to Wikipedia, one gram of plutonium-238 generates approximately 0.5 watts of thermal power. Thus, 2420 tonnes of Pu-238 will generate 1.21 GW for decades.

An alkaline AA battery weighs 23 g and can put out just over 1 watt of electrical power without overheating. You would need 27830 tonnes of them to output 1.21 GW for about 2 hours.

A golden hamster weighs 125 grams and apparently generates a maximum of 0.4 watts (according to google). This means you need about 378125 tonnes of hamster to generate 1.21 GW for a few hours.

Thus, PU-238 is clearly the most practical solution of those mentioned.

Comment Re: cultural artifact how? (Score 1) 95

The name "Uluru" is used as the primary name by the Australian government and in school textbooks. Though ordinary people have the right to refer to it however they like.

Aboriginal place names have always been a enthusiastically promoted part of Australia, long before Aboriginals even had the right to vote or hold public office. Why Australians never questioned calling their capital city Canberra (which may or may not mean "breasts" or "cleavage"), but a century later seem to find the name of a rock in the desert a sticking point is beyond me. My guess is 1) inertia 2) the perceived implication that this monolith means comparatively little to non-indigenous Australians.

Comment Re: We should differentiate between the two (Score 1) 141

Southern regimes consider abortion to be harmful to fetus (or as they would say: baby), woman and society. Thus, no-matter what federal courts say, they will do their darnedest to ban it. Federal rulings do have effect on the state level, but states still more or less rule themselves as they see fit (as per the US constitution). Thus, southern states are regimes that only ban things that they consider harmful to the people.

I thought someone might bring up something like North Korea. But Dixie? Too easy!

Comment Re: We should differentiate between the two (Score 4, Insightful) 141

No, you and he are making the distinction between laws that you like and laws that you don't like.

I agree that many laws, like the laws against child porn and malware are good. However if we tolerate the notion that these are not political issues since they are stemming from the natural order of things, then we must tolerate that to others, that the list of natural apolitical issues may be broader than they are to you and banning other things is not a political issue either. There is not a regime on earth that bans things that it does not consider harmful to the people. Remember that.

Comment Re: And so it ends. (Score 1) 55

The Chinese Internet has been essentially separate from the other one for some time now. At least in that Chinese users rarely access foreign web services, foreign users barely access Chinese web services and the latency and reliability is punitive if they try. Problem is, the Chinese Internet is not just insular, it's also a bit of a mess internally. Granted

Comment Re: A right? (Score 0) 114

Facebook's raison d'Ãtre is to provide a non-anonymous online forum. While plenty of people like me or whoever happens is reading this post, are happy to talk to "Anonymous Coward" or "donscarletti", there are many people who would rather not do that. Facebook is there for such people.

Many people I know have no Facebook profile whatsoever. I have a Facebook profile, on which I just share pictures from when I travel and sometimes write short updates about where I live and where I work. I do not write anything political, anything praising or criticising other people, anything showing me in an unfavourable light or anything I would not want strangers to see connected to my name. Many people I know post whatever pops into their head no matter how embarrassing since they don't believe in the need for anonymity. Whatever they do, they chose to do.

Facebook is the social network for those who do not like and are threatened by anonymity. Using an alias on Facebook is like wearing clothes in a nudist colony. Transgender people are welcome on Facebook, just like religious people are welcome in a nudist colony, but it cannot bend its rules for everyone's specific situation.

Comment Re:Trading on tragedy (Score 2) 105

My guess this that this made by HIV infected people as a service to others with the same condition, rather than a money making activity, so I don't think we can question the motives of the people providing this service as being exploitative.

However, they should have protected their users' information far better, given the special privacy requirements that their users have, especially in light of the recent Ashley Madison breeches. Blame is not a zero sum game, unless it's falling prey to a 0-day exploit in a third party system, getting hacked is 100% the service provider's fault, even if the hacker is also 100% responsible. Even in the case of 0-day exploits, steps should be taken to contain potential breeches and so the provider at least shares part of the blame.

Furthermore, when someone makes a very credible and sincere sounding threat to infect the family of the perpetrator with a deadly and incurable disease, they should be dealt with according to recent precedent regarding people who make online death threats.

Comment Re: How about (Score 3, Insightful) 93

There is nothing inhuman about being managed by a straight talking lead who tells you exactly what you are doing wrong in blunt, uncertain terms.

What is inhuman and undignified is being managed by HR, to whom you are a number, and follow policies that dictate how your team is to communicate and what you are allowed to say.

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