Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
DEAL: For $25 - Add A Second Phone Number To Your Smartphone for life! Use promo code SLASHDOT25. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. Check out the new SourceForge HTML5 Internet speed test! ×

Comment Re:First example of an anti-clickbait headline? (Score 1) 226

Europeans usually require a lot fewer workers for a similar TBM project than Americans do. Don't know why that is.

Labour costs. We automate the shit out of things because labour is expensive. You won't find many valet parkers or doormen in Western Europe either.
Not to mention Walmart greeters. Are those for real? How is it possible that a discount store can afford to pay someone to mostly just stand around? It boggles my mind to think of the income disparity that makes such a job possible. What do those people get paid?

"Greeter" is just a euphemism for "person who watches the door to make sure people don't shoplift stuff."

Comment Re:First example of an anti-clickbait headline? (Score 2) 226

He doesn't claim to already have new tunneling tech. He's just done some back of the envelope, first-principles calculations to show it should be possible in theory to go much faster. Typical Musk.

So does he have a faster TBM right now? Definitely not. It'll be interesting to see if he develops one, though. I suspect just reducing the man-power and increasing the up-time would give a significant boost to performance-to-cost, though. Europeans usually require a lot fewer workers for a similar TBM project than Americans do. Don't know why that is. (Or you can also think of it the other way around: for a given number of workers, you can get a lot more tunneling done, thus making tunneling cheaper and more appealing, thus increasing the number of tunneling projects you can afford to do.)

Comment Re:Son of a b... he's got a world domination plan (Score 2) 226

Much more money in building a mega telecommunications satellite constellation in low Earth orbit, which SpaceX has been working on for years now. You have 7 billion potential customers. The market for platinum group metals (even if you were able to get as much as you wanted) is globally much smaller and lower value than telecommunications.

Comment What got Elon moving was employee safety (Score 5, Informative) 226

Not mentioned in the summary is the fact that what got Elon moving on this idea was when some of his SpaceX employees were hit by a car crossing the street to their parking structure:

"A news report about three SpaceX employees who were hit by a car on Dec. 17 after leaving work. The incident occurred at 2:15 a.m. About three hours later, SpaceX CEO Elon Musk posted the following Tweets:
@elonmusk Traffic is driving me nuts. Am going to build a tunnel boring machine and just start digging..."

SpaceX has been trying to get a pedestrian bridge built there for a long time, but haven't been able to get permission from the city (blame NIMBYism or just bureaucracy). But with the tunnel, they're able to start digging down without permits on their own land (still need permission once they start digging under the street, of course).

Comment Re: Imagine the reverse (Score 1) 1069

I would imagine the reverse if Hillary had been supported by Chinese hackers (according to most experts in this alternate reality).

In reality, the whole point of the electoral college is to 1) double-guess the voters and 2) maintain power for slave states. I think there is no hope that the electoral college can do 1, because if the EC had called HRC due to defectors, then the far right wing probably would've violently responded. It honestly could've been worse than Putin-supported Trump. So that point of the EC is impotent. The electors won't check ignorance in or deception of the populace, even in the case of foreign influence. Things are simply too partisan for the electors to function as a safety valve.

And 2 is hardly a good reason for the electoral college, though it no doubt was essential in getting the slave states agree to become part of the US. And we still have traces of this racist past in felon laws, voter ID laws, removal of sufficient polling places in certain districts, etc.

So I think the EC is largely an artifact of the past. If we just went with a straight popular vote, it'd be more fair, and it'd require appealing to a wider voter base. Perhaps Trump could've still won, but he probably couldnt afford quite so many winks and nods toward the real racist elements in our population (who were not a majority of his voters but were his most ardent supporters). And that would be a superior result.

The main arguments against going for such a system is that it shifts the balance of power away from disproportionately favoring certain voters. So it's unlikely to change anytime soon.

It might be for the best if defectors were simply not allowed.

Comment Neural Net Processor... (Score 4, Funny) 186

"To make sense of all of this data, a new onboard computer with more than 40 times the computing power of the previous generation runs the new Tesla-developed neural net for vision, sonar and radar processing software."

So what you're saying is... the cpu is a neural net processor, a learning computer.

Comment Re:self-driving or assisted driving ? (Score 1) 186

The new hardware is for eventual full self-driving. Not autopilot. (Autopilot in airplanes is "assisted driving," too, but is still called autopilot... That's why Tesla chose "autopilot" instead of "self-driving" as the label for their first-generation capability.)

And yeah, there is a warning that goes off if the driver takes their hands of the wheel.

Posters better learn to actually do research before posting. Oh wait, this is the Internet, that'll never happen. :P

Comment Re:Radiation (Score 5, Interesting) 412

It's almost impossible to die of space radiation overdose. The galactic cosmic rays can't kill you via a radiation overdose, they're dose rate is much, MUCH too low.

The only thing with a high enough dose rate is solar particle event. And, in fact, there are very few that are strong enough to kill you (but note, there are winter or thunderstorms that can easily kill you if you're unprotected on Earth). One has occurred, however, in August of 1972, with a dose of about 1 Sievert, but it'd only be that high if your only shielding was a thin space suit ( here's a source for that). If you were inside a capsule or on the surface of Mars (shielded by the yes-still-significant Martian atmosphere), you'd be totally fine. Even 1 Sv not really enough to kill you. You need about 2 Sv to really be in danger of immediate radiation overdose and death. But you could vomit in your spacesuit and suffocate. However, these events are not instantaneous, you'd have a warning and the events occur over a period of an hour or several hours, so you have enough time to get inside or behind a rock or something.

No, it's nearly impossible to die from acute natural radiation overdose in space.

You'll survive the trip. The worry is about an increase in occurrence of cancer when you get back. However, in any case, the risk of cancer from living in space is less than being a smoker. Although, given the huge deal we make about the space radiation issue, you wouldn't know it. You'd think you'd die instantly or something, which just isn't true.

As far as how to deal with it, well Mars' surface has a much lower radiation dose from GCRs and especially solar flares. You're half shielded by the planet itself and secondarily by an average of around 40 grams per square centimeter of CO2 mass, maybe more at lower altitudes. Additionally, just massive amounts of rock or dirt work great. And water is more effective per unit mass.

On the way to Mars, your best bet is to shorten the trip to 90-100 days as Musk suggests, and perhaps use your supplies (water, food, maybe propellant) to shield you from solar particle events. That'd reduce your transit dose to a manageable amount. And you can also use drugs like Amifostine to avoid some of the radiation effects, especially the effects of acute radiation (we're unsure if Amifostine helps for chronic radiation). But once on the surface of Mars, it's possible to reduce the dosage to arbitrarily low levels.

But again, these are long-term health effects, perhaps like you'd see in any kind of hazardous environment. But you'll be able to perform the mission just fine.

Comment Re:Seems Promising, but Let's Not Get Too Excited (Score 5, Insightful) 170

I'm all for replications, HOWEVER: This isn't psychology or medicine. If a single, transparent, well-documented study shows that volcanic rock (of a common and well-characterized type) quickly locks up CO2, then it's not a fluke.

Science works differently in different fields because some things are easier to fundamentally understand, even with a sample size of n=1, than others where fundamental understanding is basically non-existent (i.e. we don't actually know how the mind works on a fundamental level) and you have effects so small (with so many confounding factors) that you need n=1000 to have any hope at statistical significance.

Comment Re:I predict.... (Score 4, Interesting) 224

Nothing in what you just said suggests why you think the mission will certainly end in death. That's a bold prediction, and not one anyone can make.

For some stupid reason, many people seems to conflate "some risk of a bad thing happening" to "it's a certainty that the bad thing WILL happen and will happen to everyone every single time." It's how NASA's 3% cancer risk from space radiation from a Mars mission becomes "your organs will be boiled! and it's impossible because you'll die during the mission from space radiation." This is just dumb. Space radiation isn't even as bad as smoking, and except for well-characterized and easily mitigated problems with acute doses (the biggest risk is if you have electronics which can't withstand the radiation and so fail, but that's easily engineered away), you're not going to die during the mission at all.

The first Shuttle flight, for instance, had a, I don't know, 10% chance of failure. It worked, because if you have a 10% chance of something happening, that means that you also have a 90% chance of it not happening.

I predict that getting to the surface of Mars in 9 years is much more realistic technologically today than getting to the Moon in 1969 (just 7 years after JFK's 1962 Rice University moon speech) was.

And the first flight probably won't kill anyone.

Slashdot Top Deals

"In the face of entropy and nothingness, you kind of have to pretend it's not there if you want to keep writing good code." -- Karl Lehenbauer