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Comment Re:A step forward, but... (Score 1) 399

Even when practical, we're still talking very big, very expensive plants

That's actually not true. When you look at the Lockheed Martin Compact Fusion Reactor, it's being designed to be small enough to fit on an airplane. It's a lot bigger than a "Mr. Fusion", but compared to a typical fission reactor, it's tiny.

Comment Re:No thanks (Score 2) 326

Just for the edification of the other readers here, which parts specifically do you feel you don't have to follow?

For the record, I know exactly which ones I would choose, but I'm interested to know what exactly you think makes Stallmann a 'crazy outlier'. Because, in my estimation, it would take a lot for someone to qualify for that kind of labeling.

On a number of occasions RMS has been asked how professional software developers can make enough money to earn a normal middle class income using only Free software licensing, and his response has been that earning money should not be a priority, to the extent that if a developer cannot earn enough money to support a family, that's ok. Software developers shouldn't have children. (example link)

If he had said that most software developers shouldn't expect to have as much money as Gates/Ballmer/Zuckerberg/Jobs/Ellison type people, I'd have been ok with that, but to take it to the extreme that you should deny developers the ability to have children, one of the most basic and fundamental life experiences, that was what tipped the balance into 'crazy outlier' in my opinion.

Comment Re:Autonomous cars can't use V2V (Score 1) 475

V2V isn't just for collision avoidance. You need this kind of communication to safely narrow the following distance to form "road trains" at highway speed. This both allows more cars to fit on the same road and reduces fuel consumption due to reduced air resistance in the following cars.

For example, see the SARTRE project.

Comment Re:Resolution wars (Score 1) 70

The idea is not to scale the whole image down to 300x400, but to crop it down. There isn't space on a phone to include a mechanical zoom lens, so you either need to use "digital zoom", or just take a wide shot and crop it down to the part you want later. A higher than necessary resolution sensor for full image shots is what allows a cropped image to still look sharp.

Comment Re:Oh, not again. (Score 1) 401

As a practical matter, there's a widely used program that tries to solve the halting problem by formal means - the Microsoft Static Driver Verifier. Every signed driver for Windows 7 and later has been through that verifier, which attempts to formally prove that the driver will not infinitely loop, break the system memory model with a bad pointer, or incorrectly call a driver-level API. In other words, it is trying to prove that the driver won't screw up the rest of the OS kernel. This is a real proof of correctness system in widespread use.

The verifier reports Pass, Fail, or Inconclusive. Inconclusive is reported if the verifier runs out of time or memory space. That's usually an indication that the driver's logic is a mess. If you're getting close to undecidability in a device driver, it's not a good thing.

Doesn't the fact that it includes an "Inconclusive" category pretty much mean that it absolutely does not try to solve the halting problem?

The halting problem doesn't state that you can never determine if any specific algorithm halts or not, just that there exists some algorithms which will be inconclusive for any finite bound on the time used to determine if it halts or not.

Comment Re:PDFs are programs for printing 2D objects (Score 1) 258

A pdf file is a program, written in the postscript language, directing a 2D printer to create some 2D object. I can't print copies of someone's book and sell them without permission based on the argument that the book is the output of the PDF program.

I don't see how adding an extra D changes that.

It doesn't. But not all pdf's are copyrightable.


You can't print someone's book because the book is a work of literary authorship. If you get a non-copyrightable pdf, such as a simple list of facts or ingredients, then you can print that and sell it. We will likely see something similar happen in the 3D printing world.

At issue here is not whether or not the printer has two dimensions or three, but rather if the underlying object would be considered an original work of authorship. Probably not.

If you compare this to the fashion industry, for example, where a designs for clothing are *not* eligible for copyright. The fashion industry has responded to this by elevating trademarkable labels to be elements of fashion themselves. I can take a Tommy Hilfiger t-shirt and produce another shirt with its dimensions exactly, but I can't put that logo on it.

Comment Re:#1 - Not managing the pointers and memory yours (Score 1) 394

#2 - Initialize all variables to known values. int i; doesn't cut it. int i=0; does.

True dat. Lots security pitfalls here too -- not just garden variety bugs.

This is a pet peeve of mine. It's very bad advice to throw in meaningless initializations. If a variable has no meaningful value, you want tools like valgrind to be able to recognize this and catch code that tries to use this value. If you set it to 0, but then don't mean that variable to be read without being set to something else first, you've done yourself a disservice.

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