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Comment: Re: just put a motor on the elevator itself (Score 1) 235

by arth1 (#48926067) Attached to: Engineers Develop 'Ultrarope' For World's Highest Elevator

Elevator brakes are one of the most elegant solutions known to man, and perhaps more crucial to the continued popularity of the cabled elevator. The brake is held open by spring tension generated by the interaction of the elevator and the cable. If the cable gets cut, the brake engages. That's it. Any other type of elevator would need a more complicated break system. Detection of fault conditions would be a separate action that triggers the brakes. That means delays, and the possibility of errors. It is practically impossible for a properly built cable elevator to plummet. You cannot say the same for any cableless concept design. One of the simplest ideas in legal liability is that if you opt to do something the more dangerous way, you're liable. You must have very good grounds to justify the risk.

You miss that in a pinion or cog driven elevator with the motors in the building, there is no need for emergency brakes - being stationary is the default state. Only if a motor moves the cart along will it actually move - up or down.
To me, that seems like far less risks than having a system where you need emergency brakes for safety, no matter how elegant.

And this system is in use in many assembly lines. The motors are stationary, and the carts won't move unless driven. And while most are horizontal systems, there are vertical ones too. Boxes with holes or pinions on the side are lifted or lowered by cogwheels, and there is no possibility of them falling. They can reach quite high speeds too, unlike the typical self-driven pinion-and-rack lifts that you see on boatyards and libraries.

Comment: Re: just put a motor on the elevator itself (Score 1) 235

by arth1 (#48920975) Attached to: Engineers Develop 'Ultrarope' For World's Highest Elevator

The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.

Not necessarily, no. Put fixed motors on the shaft walls, not in the elevator, and put pinions on the outside walls or corners of the elevator. The only extra weight would be of the elevator itself, less the weight of the hanging cable which elevators today have to move, and less the weight of the braking system, which would now be in the building, not the elevator.
And the much smaller building mounted motors can recuperate some of the energy whenever the elevator is descending.
Because each motor would only have to lift the elevator for a small distance before the next motor takes over, I imagine that higher speeds can also be attained, with less energy expenditure.

Comment: Re:Coding vs. literacy (Score 1) 199

by arth1 (#48915523) Attached to: Why Coding Is Not the New Literacy

You seem to have taken this very personal, resorting to personal insults for a post that had nothing whatsoever to do with you.
I suggest you change the relationship and automatically score mod my posts so you don't see them, because I will keep on ranting about things I feel like ranting about, out of the blue, without taking your feelings and opinions into consideration. They're worth exactly nothing to me - sorry.

Comment: Re:Coding vs. literacy (Score 1) 199

by arth1 (#48914105) Attached to: Why Coding Is Not the New Literacy

What you talking about is spending 80% of total effort on 20% of the features of the product. Often these features are not even readily visible to anyone.

Apps not freezing or crashing or becoming unusable by the customers aren't features.
They're side effects of programmers (among other things) actually understanding the underlying system and what happens when you poke the beast.

Comment: Re:First Sale (Score 1) 454

Exactly right! What a lot of people don't understand is that the First Sale Doctrine is a defense not an offense. In other words, if you buy a copyrighted item, like a book, and resell it, the First Sale Doctrine protects you from getting successfully sued by the copyright holder for doing so. In other words, it is a defense. It does not however, put any obligations on the publisher to provide any support to ensure that these later customers can use the product.

Neither does it give them a right to burn my book.

The problem here is that you don't buy a game. You buy a license to use a game. They revoke the license, which is their right, but by doing so, you are no longer bound by the license terms either, which includes the payment you made. Depending on the jurisdiction, you might have a good case for winning a small courts claim or similar, covering the purchase price and reasonable legal expenses.

Comment: Re:Coding vs. literacy (Score 1) 199

by arth1 (#48911695) Attached to: Why Coding Is Not the New Literacy

I'm not talking about messing with IO requests. I'm talking about understanding what happens when they're issued, whether it's by you or a library you use, so you don't lock up a system for no good reason.
But these days, this is considered "arcane knowledge" and is ignored, in favor of blindly using magic toolkits and libs, and blaming the system for not performing when it's the app that is badly designed out of ignorance.

Comment: Re:yes, programming, like poetry, is not words, un (Score 2) 199

by arth1 (#48911271) Attached to: Why Coding Is Not the New Literacy

I've always thought programming is more like writing POETRY than just being literate

I disagree. You don't hire poets to design a space ship - it may be pretty, but it won't work. You don't hire sci-fi writers either - it may look workable to the masses, but the pesky laws of physics and economics will have their say.

Programming is more like engineering. As in being able to construct something that actually works.
Coding, on the other hand, is more like manufacturing, where you produce something based on what the engineers have come up with.
But too often these days, it's not engineers that came up with it, but bloody poets, and the poor coders have to steal bits and pieces they don't understand from people they have no reason to trust in order to make a workable mess out of it.


Comment: Re:Coding vs. literacy (Score 4, Interesting) 199

by arth1 (#48911229) Attached to: Why Coding Is Not the New Literacy

Hmm. If you can't read, you are restricted to looking at pictures. If there is someone to read for you, then you can hear the parts of text they choose to read for you, otherwise you are pretty much restricted to children's picture books. A lot of what happens in the world is simply a mystery to you.

That's happening more and more. I find myself going to web sites looking for manuals and specs, and all they have these days are videos. I don't want videos, I want text, with orders of magnitudes higher information density, searchable and editable.

Dumbing down seems to be across the board. User interfaces, recipes, clothing, handwriting, ability to add and subtract without a cash register or calculator, you name it.

And yes, "coding". Which has taken over for programming. The typical modern "coder" builds houses out of Lego. They may look colorful and shiny, but at the end of the day it's still Lego.

Gone are the days of programmers who actually devised algorithms and discussed them, instead of Googling for something that might be pressured into service. People who would understand what an OS call actually did, instead of treating it as magic. Something as simple as describing what happens behind the scenes when doing an IO request is beyond many newer coders (some of which I work with).
Programmers, they aren't.

We have to start expecting more, and stop rewarding and kowtowing to incompetence.

Comment: Re:Simple solution (Score 1) 422

by arth1 (#48896783) Attached to: Ask Slashdot: Where Can You Get a Good 3-Button Mouse Today?

I use a real computer (what's an "unreal" computer anyway?), and I paste using right-click -> "paste" or CTRL-V, or SHIFT-CTRL-V if it's in a terminal. What's wrong with that?

It requires cooperation from the program you paste into.
With X Window System where left-mouse-drag automatically copies and middle-mouse pastes into any program as if you had typed the text, you don't have to worry about whether paste is supported or not, or how it does it (Ever tried to paste from a web page into, say, Outlook, and you get an unwanted table around the paste because what you copied was in a table? Or got a font or text color you didn't want?)

With mark / paste on middle-mouse, you can be fairly certain that you only get the text you marked. And even more importantly to some of us, it works great with partially overlapping windows - just because you paste some text into a window doesn't make that window pop to the front and obscure what you really were interested in, most likely what you copied from.

Comment: Re:Interstellar missions... (Score 3, Insightful) 210

by arth1 (#48891273) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

This is why a desert can go from 100F to near freezing in a matter of hours when the Earth rotates and the desert is radiating heat out into space.

Deserts are not vacuums. Deserts cool down at night mainly through air convection. High altitude air on the planet's night side is less buoyant, and is replaced by warmer air from lower altitudes, and this process repeats all the way down to the surface. Katabatic winds are often a result, which the California "sundowner" winds is a good example of.
Needless to say, that isn't much of a concern for the microclimates of spacecraft.

Comment: Re:Interstellar missions... (Score 5, Informative) 210

by arth1 (#48890895) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

Deep space tends to be very cold

This is misleading at best.

Space in itself is a near vacuum, which (a) has no temperature of its own, and (b) is a wonderful insulator. Which is why a thermos uses vacuum for insulation.
Objects in space can become very cold over long time spans, as heat slowly radiates away without being replenished at the same rate. But space itself doesn't cool them down.

Voyager 1, which is the operative craft that's been in service the longest and receives the least amount of heat from the sun is, after most of the heaters have been turned off to conserve energy, running at around -80C temperatures. That's a veritable furnace compared to other older objects in space that have radiated away more heat over much longer time.

Also, you say "chemical batteries". Well, yes, it is, but this is a dry battery. The composition doesn't change with colder temperatures, unlike wet batteries where liquids freeze. Dry batteries don't have that problem, which is why it is interesting.

Comment: Re:Why lay fiber at all when you can gouge wireles (Score 1) 200

by arth1 (#48890259) Attached to: Verizon About To End Construction of Its Fiber Network

The free market strikes again!

Let's not forget the billions in tax breaks and incentives that the telcos got in return for a promise to make sure everyone got broadband, no matter where they lived.

But will they be punished? Well, look at campaign contributions and make up your own mind.

Comment: Re:Why not a full-on Linux environment? (Score 0) 169

by arth1 (#48890183) Attached to: Google Just Made It Easier To Run Linux On Your Chromebook

If they are making it easy to run "normal" Linux, why not install the appropriate libs and allow Linux apps to run side-by-side with Chrome apps?

What are Google's business models? Ads and tracking.
Installing anything that is going to make it easier to circumvent either is not likely to happen.

Comment: Re:Pedantic, but... (Score 2) 169

by arth1 (#48890147) Attached to: Google Just Made It Easier To Run Linux On Your Chromebook

You summoned him!
Apparently he doesn't have a /. account, but still is a reader.

He probably doesn't like the license for using the anonymous account, and I can't really blame him.

Anyhow, I think you're triggering a /. law here: As the mentioning of RMS in a Slashdot thread grows, the chance of Bruce Perens posting approaches unity.

When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle. - Edmund Burke