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Comment: Re:240km/hr? (Score 2) 419

by rolfwind (#48392629) Attached to: Japanese Maglev Train Hits 500kph

Yes.

Fast trains need well maintained tracks, specially built for the speed, and the curves also have to take that in mind. The advent of cars and later planes have pretty much undermined rail in America in terms of people transport and many lines are only suitable for slow-moving cargo trains, some as low as 10mph.

We're talking track that will bounce up and down out of the ground a good 18 inches into the air. I've seen this often enough with an approaching train in some sections. That track couldn't take 60 mph trains, let along several hundred mph.

America, may as well be trackless for the most part for rail that is in any condition and design for high speed rail. Buses have pretty much put an end to trains as a serious passenger mover, too bad they will never reach speeds that would make it a serious distance mover for anybody but the person with time on their hands, a tourist or sightseer.

Comment: Don't plan on reading too much (Score 1) 223

by rolfwind (#48389737) Attached to: Ask Slashdot: Programming Education Resources For a Year Offline?

I'm going to India for over a year, coming up soon. Although my company is sending me to essentially train my replacements, and then another round after that... sigh, at least the money is good.

I expect to have internet (I don't see how not) but Idk how steady or fast it is in that area so I'm downloading wikipedia on a usb drive just in case. I have my own favorite books, like Pointers on C by Kenneth Reek but that's book specific. As well as some Lisp history and underlying math (original paper).

There is the classic SICP, Knuth's Art of Computer Programming, Concrete Mathematics, etc.

Of course this is all heavy, so I'm putting it in a kindle or tablet. A b/w kindle with some type of manual charger as backup would be ideal.

But you know better than I what your goals are. Don't pack too much, especially dead tree books. Just 1 or 2 of those. You're going to the Himalayas! Enjoy it. Plan on getting through 1 challenging book and don't waste the rest of time reading. It'll still be there when you get back.

Comment: Roomba for skyscrapers (Score 1) 203

by rolfwind (#48386121) Attached to: Window Washing a Skyscraper Is Beyond a Robot's Reach

I'm going to say there will be a window roomba for skyscrapers within a decade. It's too lucrative a market not to pursue.

The improvement in suction cups have been here for a while. Short of some innovative cleaning system that require little/no water, resupply and dirt offloading can be handled by some ancillary robot that runs back and forth to some main hub.

All that will really be needed is some safety system to keep it falling from pedestrians. If it's a cable, then the ancilliary robot might be done away with as tubing can feed solution downward although I'm dubious about a capable pump upward without weighing the robot down too much.

What will stop it is that human labor is still cheap. Unless insurance costs price them out of the market, robots are doable but fall under that "more trouble than it's worth" niche. So while someone may develop something, not sure on uptake.

Comment: Re:No. (Score 1) 237

by rolfwind (#48383131) Attached to: Will Lyft and Uber's Shared-Ride Service Hurt Public Transit?

It will not. It's much cheaper to take public transportation in most cities; the only time it would make sense would be on longer trips, because you are saving alot of time by taking Lyft or Uber, but you sure the hell aren't saving money.

I think it will hurt because people will always pay a reasonable convenience fee. Oh, you're right on steady customers of public fare that take public transit daily. But there's all those people taking special trips and the like.

When I was a college student, I had no car, and a 7 minute car ride to the grocery store, 20 mins and checkout, and 7 minute ride back turned into a 1h30m to 2hr15m with the bus depending on time of day. Would I have taken lyft or uber over the bus for a few bucks? Hell yes. It's not as if the bus ride allowed me to study, it was too short for that, 15 mins at most, it was the waiting at a stop not really conducive to study.

But why is this phrased on /. that it be a problem if the answer is yes? Competition is a good thing. And even government monopolies shouldn't be protected forever.

Comment: Re:analog computer (Score 1) 91

by rolfwind (#48342447) Attached to: fMRI Data Reveals How Many Parallel Processes Run In the Brain

On a brain cell level, but if we zoom out, so to speak, there should come into scope some system we can label where the brain does multipe things at once reliably: balance, process sound and vision, etc.

What interests me the most are the levels of subconscious/consciousness and where all this combines to create our singular, waking awareness.

Comment: Re:The number one thing (Score 3, Informative) 250

Highly disagree, OP sounds like a ripe candidate for solar water, not to be confused with photovoltaics. Solar thermal is highly efficient and pretty cheap in comparison.

A modest setup would need only three hours a day sun just to supply hot water for daily use, and a bigger setup or more time for supplying hot water for heat (radiant heat using water is extremely common there).

He's asking for heat and not electricity per se, solar water is ideal for that and many times cheaper than PV for the same results.

Comment: Where will decent software come from? (Score 5, Interesting) 111

Eh, I think the weakspot in any 3d printing will be the software. As a hobby engineer, I use Solidworks which is several thousand dollars (luckily already on some of my employer's computers so they foot the bill).

But at home, I tried FreeCad, Cubify Invent, and several other free or cheap options and I find them invariably terrible, at least as far my limited experience can discern. FreeCad in particular, asides from UI nonintuitive issues and heaps of bugs (various cuts and operations simply disappearing for no reason), is only up to v0.14 since launching in 2002. It's like the Gnu Hurd of that genre.

I don't see how the 3D printing revolution will remotely come to town without something decent on the software front that's $200 or less.

*Posted this yesterday in a thread, but was too late for anyone to see it.

Comment: There is no free anything (Score 2, Insightful) 262

by rolfwind (#48264749) Attached to: Power and Free Broadband To the People

You don't help the poor by giving them more free handouts. All that will occur is the middle class will pay for it through price hikes and something similiar.

Time and again, history has shown a healthy middle class is the best road to alleviate poverty on a grand scale. Well guess what? It's the middleclass that has to pay for entitlements by and large (especially through fica taxes), taxing them more after decades of no real wage increases (since the 70s iirc) will have the opposite effect.

The best road would be to block the merger, encourage legislatively more competition, prices will drop, and it will help everyone (except Comcast and Warner of course).

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