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Comment Re:Compiler optimizer bugs (Score 1) 268

> Seeing your code work on another computer tells you nothing at all

Oh, it can be quite useful. "Another computer" often means "a system that has not had the interesting local undocumented developer modifications that have replaced basic perl modules with too-new or too-old CPAN dependencies". Or it can mean systems that have not had the latest software update with the new regression in a system library, or a system where a developer has not been tuning sysctl parameters and SELinux. I've run into all of those, in the last week.

I'm afraid I'm unable to post some of my best failures, they're too personally identifiable to me or to a client or colleague. I will mention my most galling, most frequent style of bug in the last five years: It's the complete refusal to bundle software. To just "compile from source" or haphazardly integrate components from CPAN, from pip, from maven, from apt or RPM or other sourceforge or github or any unmaintained, untested repository scattered anywhere in the world without the slightest dependency testing or component verification. Cleaning up the mess is paying a great deal of my salary right now.

Comment Re:Not a monopoly anymore. (Score 1) 367

Oddly, the last time I _chose_ to use Firefox was several years ago. I occassionally choose to use Intenet Explorer to get MS updates, and to work with corporate sites that insist on "Microsoft only" features. But I discarded Firefox in favor of Chrome some time ago, simply for the better performance and compatibility with more websites.

Comment Re:How? (Score 1) 378

I've gotten random links to porn. I'm afraid I also get social email from colleagues and clients who say "Hey, check this out". And I've also had clients who run pornography and escort services. The smaller ones don't always pay their bills, but adult traffic is a _very_ big provider and consumer of high bandwidth Intenet traffic, so they're a difficult market to ignore.

Comment Re:Blimey (Score 1) 516

I had to look deeper to see that you are correct. There _have_ been several NASA published designs using microwaves or other EM for ordinary thrust, I'm afraid I thought the original article concerned one of those.

On review, as I mentioned elsewhere, I'll bet that this is really a "Dean Drive". The Dean Drive never worked well outside the designer's workshop, was never tested properly with a basic "pendulum" test, and seems to have been a basic "oscillation thruster": it interacted with the floor under it to provide net thrust. That would mean the system is not really "sealed", it's interacting with its environment in some subtle way.

From the description at, I'd guess EM interaction with the walls of the stainless steel vacuum chamber. And one of hte people I'd want to review the experiment would be James Randi, who's been helping debunk "mysterious mental force" claims for decades, and has a professional magician's eye for misdirection and sleight of hand.

Comment Re:The argument is "leaky" at best too (Score 1) 195

> evolution does not consider risks and benefits, changes are random

Interestingly, not all changes are random. There are some fascinating changes in DNA triggered by environment, many of them studied as "epigenetics". And there are certainly changes in organisms that are defensive responses to environment. The darkening of skin under sunlight is a classic example. Evolution occurs at _many_ levels. These include environmental, biological, behavioral, cultural.

Comment Re:Not the best summary... (Score 5, Insightful) 195

> The only group that is really helped by other people's vaccinations is a small percentage of the population that cannot get vaccinated.

You obviously don't remember polio. I do. You apparently also don't remember when the flu killed so many people in winter, and fail to understand how modern cities and especially air traffic make pandemics far more likely and far more dangerous.

Comment The Dean Drive is back (Score 3, Informative) 516

There was a similar set of claims roughly 60 years ago for the "Dean Drive" a "reactionless drive" that did not seem to use propellant. To casual review, and letting it push your hand, it seemed to work, and a great campaign for research and to ignore the sceptics of the time was headed by John W. Campbell, the editor of Analog magazine. Analog was, and remains, a science fiction magazine specializing in hard science and science fiction based on it, and it had many real scientists as readers and contributors, so the Dean Drive received quite a lot of attention.

The Dean Drive has since been pretty thoroughly debunked as an "oscillation thruster", a device that relies on tuned "slipping" on the floor it rests on to creep forward and even to provide a modest thrust, _pushing against the floor_. The designer was never willing to allow a full "pendulum" test, or careful testing outside of his own workshop, and there seem to be dozens more of similarly patented "reactonless drives". The ones that work at all also seem to be "isicllation thrusters", pushing against the floor or the mehanism in which they are mounted.

Comment Re:Blimey (Score 1) 516

> As an added added bonus, such a drive would accelerate faster at a given thrust, because of the absence of reaction mass.

If only they didn't require an actual motor, or storage system for the energy for the microwaves. Since the maximum _chemical_ energy available in batteries is quite close to that of a good chemical propellant, it's only a big benefit if the energy for it comes from elsewhere, such as solar cells or a quite large nuclear power source. And if you have low mass space based solar cells, you can use either a solar _sail_ based system, or a transmission base to propel target spacecraft with a larger, more stable microwave source.

Comment Re:Safety (Score 1) 63

I very much agree with you. I'd not expect immediate, dangerous coupling from a relatively low intensity coupling such as a recharger might product, even if someone slept with such a device under their pillow and wore loop earrings.

It was the reasoning from viperidsenz that because MRI is safe, inductive recharging is safe that I meant to call into question. MRI, misused or accidentally mishandled, can cause injury and death. The scanners devices are not a good starting point for comparison of safety.

Comment Re:This is the WRONG focus (Score 1) 63

> It is easy enough to plug it in.

It's also quite awkward and destructive to the connector if any mistakes happen, and lugging around the cabling is awkward. It's hardly a new idea, "" has been selling such stations for years.

Unfortunately, the customized charging case you have to keep the phone in for Powermat to work are quite expensive and make the phones unwieldy.

Comment Re:Safety (Score 1) 63

Thank you for pointing out that a small loop may not cause injury. A casual look at published guidelines shows that they say to remove _all_ metal, and some metal may be safe if designed carefully. But some guidelines accept that wedding rings, in particular, may be impossible to remove without cutting them and accept the modest risk. I'm looking particularly at this as an example:


So you've raised a very good point, thank you for the refinement. In turn, I'll point out that not all patients in an MRI are conscious, and that not all loops are worn on the hand. There is a particular case, described at, where a man with a very serious head injury had a "magnetic resonance safe" pressure monitor implanted in his head. It coupled to the MRI, and the tip melted in his brain.

Comment Re:How about where you can find electric outlets? (Score 1) 40

If you rely on your phone for work messages or reaching loved ones during travel, here are some hard-learned suggestions.

1) Don't leave the house thinking "I've got 30%, that's plenty until I can find a charger!".
2) No video or audio except when it's plugged into power or someone is paying you for it, whether it is your workplace or your family's good will.
3) Use an older phone with simpler features. Real work _does not need_ large screens or high scores on cell phone games.
4) If you get bored, bring or get a book. Even a local daily newspaper can provide fascinating local politics and color to share with business contacts while traveling.
5) Carry a real battery, one that is as large as your phone. Numerous batteries with enough charge to recharge multiple cell phones work very well at long meetings, and it makes you seem well prepared if you can recharge both your own phone and the other person stuck there all day. They're also invaluable on long plane trips, commutes, or drives home when you've had no chance to recharge your phone all day.

"The number of Unix installations has grown to 10, with more expected." -- The Unix Programmer's Manual, 2nd Edition, June, 1972