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Comment Re:Pretty sad (Score 1) 156

g++ supports it with __restrict__. And if you're writing high performance code but not having support for the features of modern compilers, you're an idiot. In appropriate situations, the performance difference for using restrict or not is huge. Array-heavy tasks like image processing often get a 2-fold or more benefit with using restrict. There's very few places in the coding word where a single keyword can raise your performance that much.

Comment Re:As with all space missions: (Score 1) 200

I'll begin by stating that I I don't support such a mission, as I prefer robotic exploration. But this proposal isn't as extreme as it may sound - it's probably a heck of a lot easier than landing on a planet and taking off. It's only 640 m/s from earth escape to Venus (3/5ths that of Mars). Transit time is less and launch windows a lot more frequent. Venus offers very easy aerocapture. You don't have to deal with the randomness of the surface - your "landing" is a lot more forgiving. Your habitat is probably simpler, not having to deal with a surface (although there's a few potential complications that need to be studied, such as storms, and I don know the radiation level at the desired altitude). Keeping it aloft is easy - even normal earth air is a lifting gas on Venus. Solar energy arriving at Venus is double that of Earth. Nearly earth's gravity eliminates a lot of the uncertanties about skeletal and muscular wasting.

One of the neat things is that a person could potentially step outside without any sort of special suit, just an oxygen mask. It's a "maybe", though, as there's a few complicating factors. It's 37C (100F) at the same sort of heights that it's about 600mb; for US analogies, it's Phoenix temperatures at Mount Whitney air pressures (lower or higher for both, depending on your exact altitude - you can choose). So it's not a perfect match - but probably tolerable. But there's two potential complicating gases: SO2/sulfuric acid and carbon monoxide. Breathing them is right out, but even long-term (hours at a time) skin exposure might be problematic at the given concentrations; it's not certain whether at these altitudes they'd be prohibitive. They would however make eye protection a must at the very least, the eyes are more sensitive to both CO and SO2 than the skin.

Manned or not, the main advantage of a Venus blimp would be the lower altitude it would provide to scientific equipment versus satellites. So you'll get a lot more information on the atmosphere, which could help answer questions about Venus's evolution (and how other worlds in other systems might be). You'll get higher resolution radar imaging of the surface. You simplify to some extent sample return missions from the surface, as each sample collection doesn't have to be a self contained return mission. Etc.

One thing on Venus I'd love to see studied more is the super-reflective radar surfaces. It's now believed to be due to a "galena snow", snow made of shiny, electrically conductive lead sulfide. I'd really love to know more about the surface minerology of Venus in general.

Comment Re:Not a cargo ship (Score 3, Interesting) 116

Once again, when not using made up numbers, Green energies are the same.

Which is a very odd claim - since you produce no numbers whatsoever for "green" energy.

And you forget that natural gas isn't just a source of BTU's - it's also a major feedstock for a variety of industrial processes. (A significant portion of "oil derived" plastics are actually derived from natural gas.)

Comment Re:Meaningless (Score 3, Interesting) 173

I'd love to be able to publish these statistics for our organization, (I'd estimate we have close to a quarter million drives in the field) but there is a big hurdle in the way: legal liability. If I was to say something negative about Western-Sea-Tachi drives, their lawyers might call our lawyers, and we could easily spend a million in court fees.

The thing I think would be interesting is that we have a completely arbitrary mix of drives, based on drive availability over the last 6 years or so. We also have a mix of different service companies who replace the drives in our workstations. Our contract is such that we don't control the brands, or even the sizes, as long as they meet or exceed our specs. As a service organization, they're responsible for picking the cheapest option for themselves. If our spec says "40 GB minimum", and they can't get anything smaller than 500GB, they'll buy those. If 1TB drives are cheaper than 500GB drives, they'll buy those. And if we're paying them $X/machine/year for service, they can do the reliability decisions on their own, so if they think some premium drives will last two years longer than stock drives, they might be able to avoid an extra service call on each machine if they spend $Y extra per drive. I expect these service organizations all have their preferred drives, but that's not data they're likely to share with their competitors on the service-contract circuit.

Comment Re:As long as they get close it's a win (Score 1) 81

No, I missed the quoting the part that was (more-or-less, mostly less) correct. The parts I quoted were parts that you were wildly incorrect on, as there's considerable distance between what has been tested, and what they are testing. Even so, you're still wrong. Miss the target, by even a little bit, and it's a loss. Land hard and lose the vehicle (not due to sea state) and it's a loss. Tip over and lose the vehicle and damage or lose the barge (not due to sea state), and it's a loss.

So yes, it does matter if they miss, it does matter if they land hard or tip over - because the whole goal of the test is to demonstrate a successful pinpoint landing. You don't really seem to grasp what's being tested here and why.

Comment Re:Man, am I old ... (Score 1) 173

I don't take pictures for "posterity", or for people who outlive me. I take pictures for me, and my family, for now. While I only have thousands of total pictures, (not 10,000 per month) I can still find the pictures I want on my hard drives. So when I die, if some future grandchild wants to trawl through those terabytes in the vain hopes of finding a good picture of a great-great-grandparent they never met, why should I care? What difference would that make to me, today, in how I choose to save or discard photos?

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