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Comment: Catch them! (Score 1) 169 169

The cutting process must take some time as the bundle is large and armored.

The photodetectors receiving the light on each end of the fibers should be able to detect disturbances associated with the fiber being cut AS IT IS CUT. (If you physically disturb the fiber it affects the transmission efficiency.)

With the appropriate automated analysis (time-delay reflectometry), police could be requested to deploy to the vandals' location before they have even finished cutting through the bundle.

Alternatively, DHS' secret drones could have missiles on that spot in seconds. (I'm joking... or am I.)

Just saying...

Comment: When can we end the corporate experiment? (Score 0) 313 313

When can we end this stupid experiment of having multiple corporations try to recreate NASA's 50 years of launch experience and reliability?

If congress feels that they must cater to the private industry lobby, fine. Hold a small carrot out to encourage a competitive private space industry. But let's refund NASA to continue these mission critical activities and to actually develop a space shuttle successor.

Some activities do not work well on a corporate schedule or budget. Blackwater didn't do a satisfactory job in Iraq. No one is doing a satisfactory job with developing a private launch technology.

Please stop selling our national security out to private industry.

Comment: Good. (Score 1) 292 292

Maybe now we'll see an election where we don't actually know who has won until the voting is complete.

All of this polling has created a self-fulfilling prophecy where sketchy polls predict a winner, undecided people vote for that winner to make their vote "count," and others for or against the the projected winner don't bother to vote. Meanwhile, political candidates don't really bother to take a stand on issues unless they have verified via polling that XX% of their constituents support their position.

Let's get back to a situation where the news corporations and the 10% of the population with landlines (who answer the phone) don't actually decide the entirety of public opinion.

Comment: Re:FFS (Score 1) 412 412

If you are offended by what he said, in the context of why he said it, it says more about ridiculous you are, than he is. Political Correctness is a disease, not the cure for what ails us.

Political correctness is definitely a disease, but so sexism.

As a young(er) male researcher, I am offended by what he said. There are way to many old sexist assholes in science, who need to be pushed out. (This particular individual also needs to learn how to trim his nose hair... my god!) What is amusing is that he is actually married to a fellow scientist.

As an aside, I've made two people cry in my career due to giving overly critical feedback, and both were middle-aged men.

Comment: Re:I know a lot of this is cutting edge... (Score 1) 41 41

It's not the first time they've had problems with chutes either, however this is the biggest one they've done so far, and things don't always scale up (you need thicker fabric, etc to handle larger stresses)

From the limited video footage, the chute looked to be already torn at deployment, so it may have been doomed to fail well before it opened (though NASA have had tearing problems before, one wonders if they had built anything in to mitigate that known risk into the design)

(*i am not an expert, just an average thickie)

The parent is right. A supersonic parachute deployment will require modeling the fluid (air) and the chute's structural mechanical response in a coupled fashion. This would push current computational limits. The fact that they modeling materials whose dynamic response is poorly studied (fabric) makes it all that much harder from an engineering perspective.

Realistically, some computational modeling might get you in the right ballpark, depending on the quality of the modeler and model, but you're going to need to do a whole lot of validation testing. The three tests that NASA has schedule for the project appear insufficient, especially since it appears that their design and modeling approach is not predictive. (Sorry NASA, but it's true on this one!)

That said, this could be tested at smaller sizes and then scaled up using an analytical approach. The scaling isn't always going to be linear, however and it will require experts to identify the relevant and dominate dimensionless groups to correctly scale things. I'd recommend that they scale things down, schedule a whole lot of sub-scale tests in their supersonic wind tunnel (which you can instrument more substantially), and only field full-scale tests once they have good sub-scale predictive performance at a variety of different sub-scales, including predicting chute failure. In today's levels of high oversight on each full-scale test, they really can't afford to fail twice... especially if you can't cough up a lot of videos of subscale testing working perfectly. Frankly, if this was a for-profit company, the team would already be shitcanned based on their response to the failure: "... take a look at the high-resolution video that we’re going to get back, along with the rest of our data, to make a determination about what is going to happen." (If "high-resolution video" is the best diagnostic that you have, you're screwed. Hopefully there are strain gauges and accelerometers on each load bearing component so that you can actually conlcusively figure out what failed and why.)

Comment: Re:What's that you say? (Score 4, Insightful) 528 528

"Free". You keep using that word. I do not think it means what you think it means. They pay out the ass in taxes for that "free" education and over the course of their career, they'll pay more money than if they just took out loans and paid for it themselves. But sure, keep using the word "free" for things paid for via taxes.

You know what else you get for all those taxes? A work/life balance, health care, retirement, and a lot of other benefits.

Seriously, this excuse that Americans "save" money by paying for everything individually is crap. You pay federal taxes, state taxes, sales taxes (you have now taxed me three times for each dollar spent, thanks). I have to work out my tax liability myself, unlike the Germans, who get a government estimate. Then I pay for half of my health care premiums on top of that. Since Obamacare, premiums have gone up for me and coverage has gone down, so I pay more money for each non-wellcare doctor's visit. (And then taxes on top of that.) I get two weeks of vacation a year (which I will be unofficially penalized at work if I actually use all of it) and no paternity leave.

Let's not forget the 401K that constitutes the entirety of my retirement savings, since pensions no longer exist for younger workers in the US. (They are even taking them away for older workers now!) I also have no paid retirement health care (a future financial concern for me), so that will be an out of pocket expense too. And, on top of all that, I have to pay for college out of pocket and save for my childrens' potential college costs (and who knows if they will even want to go).

So, explain to me again how paying a 50% tax rate instead of a 25% tax rate saves me money in the long run. I still have to pay for the same things, but they are future expenses with unknown costs that will definitely be higher than an additional 25% of my tax rate.

Comment: Re:Social mobility was killed, but not this way (Score 1) 1032 1032

Any degree worth getting can easily repay itself. 1) Get a useful degree, 2) Go to a state school, 3) Quit the narcissist entitlement mentality.

Education has the best ROI, but like any investment you still have to watch how and what you invest in.

You missed the zeroth step:

0. Look at a list of salaries for graduates in each degree field.

Often this step doesn't occur to students until too late in their careers to be useful. It is a real shame that guidance counselors and some parents are not more proactive with that point. Not everyone needs a lot of money to be happy, but everyone needs "enough" money. It's important for people to pick a career that will give them that level of cash.

Personally, I think that colleges downplay this point out of self-interest to make sure that all of their degree programs are attended.

Comment: Re:Still in sad condition (Score 1) 176 176

It really speaks to the immense power, wealth and engineering skill of the ancients that they BUILT this thing so long ago.

You're forgetting the key ingredient: SLAVES.

They used lots and lots of slaves to build it. And they didn't give them workers comp or health benefits. Their retirement was probably a shallow grave.

It's in disrepair and so expensive to fix today because you can't abuse people like that anymore, although with all the retirement benefit cuts and debt restructuring, governments are doing their best to get back to that point!

Comment: What I don't understand is... (Score 1) 286 286

... how the government gets upset at Snowden and Wikileaks for giving away information that is supposed to be critical to our national security, and then goes and brags about the operational details of the Bin Ladin raid and their social networking surveillance based attacks.

Do as I say, not as I do?

Comment: Re:Fear of guns (Score 1) 535 535

If the blaster was black plastic, would you be able to distinguish it from a real gun from 100 feet away?

What you should really be worried about is:
If a real gun was put under someone's shirt or under their jacket, could you distinguish it from 100 feet away?

Because that is how a real sociopath intent on inflicting serious damage would approach a target.

He wouldn't dress up in a stupid TIGHT white suit that not only stands out like a sore thumb, but also restricts his field of view, his movement, and his ability to hide any weapons.

He'd do something that would enhance his changes of accomplishing his goals. For example, he'd dress up like a cop, walk into the school with his badge out, say he was responding to a threat, and then start killing people. There, now you have a real concern to worry about.

Comment: Re:Publicly Funded Research (Score 1) 39 39

What I don't get is why I, as one of the millions of taxpayers that funded this research, don't have free access to the paper.

Yes. I know. Preaching to the choir, OA journals, etc. That still doesn't change the fact that I find this both irritating and wrong.

You don't get free access because the authors chose not to post a preprint/author's draft online and also chose not to submit to an open access journal. Why not pay the $35 and then deduct it from your taxes? :)

Frankly, I'd be more pissed about how you also don't have free access to the Trans-Pacific Partnership agreement.

Comment: Re:North Pole (Score 4, Funny) 496 496

The north pole and a circle of lat 1 + 1 / (2 * PI) north of the south pole.

Actually the answer is the north pole and a circles of lat 1 + 1 / (2*pi*n) north of the south pole where n=1,2,3,4... etc. plus there is a slight correction because the surface of the earth is not entirely flat and so the circumference of a line of latitude is actually less than 2*pi*s where s is the arc length from the line to the south pole for the distances involved it would probably be negligible compared to surface defects.

See, if you gave the above answer, you would get a SpaceX job as an engineer due to the detailed, exact nature of your answer. Or maybe a job in their legal department.

If you just casually said "the North Pole," you would get a SpaceX job as a manager of engineers.

Steve Jobs said two years ago that X is brain-damaged and it will be gone in two years. He was half right. -- Dennis Ritchie

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