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Comment Re:Don't have to buy one (Score 1) 207

One place where I worked uses a center-punch or hand drill to perforate the disk platters, then bends them with pliers; laptop disk platters tend to be made of glass, and shatter in a most gratifying manner. Physical destruction of the platter is definitely the most effective way to permanently delete its data.

Comment Re:Jeff Bezos knows very little about solar. (Score 1) 306

Solar power in orbit actually isn't as bad an option as you may think; you simply have to go about it a bit differently. True, PV cells degrade form radiation exposure (as will any electronics used), but you can easily deploy several acres of really cheap mirrors made of aluminized Mylar film to concentrate sunlight on, say, a bimetallic thermopile (generates DC power from junctions of dissimilar metals at different temperatures, simple to make and totally radiation-hard) or a Stirling-cycle or steam-driven generator (yes, steam in space sounds utterly wacky, but it gives you a robust, radiation-hard electric generator using low-tech means).

Comment About that gravity well... (Score 1) 306

While I am generally in favor of establishing an orbital industrial base, the mention of orbiting "heavy industry" seems a bit strange. The high cost of lifting material into orbit, even with reduced-cost reusable boosters, would seem to rule out any industry where the term "heavy" equates to "raw materials that weigh a lot."

Don't expect to see, say, metals refining or glassmaking in orbit until we can access the asteroid belt's raw materials; we're far more likely to see industries with a high value-to-mass ratio, like semiconductor fabrication (which the article does mention), that can take best advantage of really hard vacuum, near-total lack of particulate contamination, and the ability to create extremely vibration-free environments. For my money, semiconductor fabrication is probably the killer app for space-based industrialization.

Comment But not necessarily over hobby model aircraft... (Score 2) 115

The FAA's authority over UAS is not as cut-and-dried as all that.
I'm a model aircraft flier and a member of the Academy of Model Aeronautics, and the AMA is of the opinion that the FAA has overreached with its new registration rule. Specifically, they believe that Congress prevents the FAA from regulating model aircraft due to an exemption in the FAA Modernization and Reform Act of 2012. The AMA's official blog has a recent article (link is below, just cut'n'paste it) which includes the following statement: "AMA has also argued that the new registration rule runs counter to Congress' intent in Section 336 of the FAA Modernization and Reform Act of 2012, otherwise known as the Special Rule for Model Aircraft." There is a court challenge in progress on this issue as well.


Now, this exemption won't cover commercial UAS, but the hobbyist model flier is very likely exempt (with the possible exception of some FPV models (controlled using onboard video downlinks rather than direct line-of-sight to the model). It should not need to be pointed out that essentially all of the "drone" troubles being encountered now are due to improper behavior that violates common sense, ordinary caution, the AMA code of conduct, and a variety of state and federal laws relating to full-scale aviation and public safety.

Moreover, the people doing these dumb things aren't likely to properly register their toys in any case, so all of these regulations are worthless in any practical sense to begin with. (I find it useful to think of this type of behavior as comparable to shining lasers at airliners: It's a stupid and potentially dangerous activity practiced by fools who won't behave themselves, and no amount of legislation will change that.)

Comment Lofstrom Loop still seems dicey (Score 1) 171

I think that a space elevator is entirely impractical for a planet with an atmosphere (and air traffic); aside from the material science challenges, there is just too high a risk of one errant aircraft or piece of orbital junk taking the whole thing down.

The Lofstrom loop cited by the parent poster is interesting, but seems to suffer from some of the same material science and fragility issues. Its energy consumption when idle is also an enormous cost factor (the power required to overcome atmospheric drag would be staggering all by itself). From a practical standpoint, I cannot imagine any organization building either one of these on Earth; the costs and risk are too formidable.

For practical space launches, the best alternative would appear to be a hybrid air/space approach similar to Scaled Composites' SpaceShip One (also used by Orbital Sciences' Pegasus satellite launch system). Your first stage is essentially a cargo aircraft, which gets your space vehicle up past the first 10 KM of altitude and the first 600 KPH of velocity without the massive inefficiency of a first-stage rocket booster. The winged second stage is either a pure rocket vehicle or a hybrid air-breathing / rocket vehicle. This system uses atmospheric lift and rocket power where each is most effective; the big airfoils and air-breathing jet turbines stay in-atmosphere for immediate reuse (this is much more cost-effective in the long term than a reusable first-stage rocket booster, as it can be reused literally thousands of times between major overhauls).

IMO, this is what the future of space launch will look like.

Comment Re:What's the point ? (Score 4, Insightful) 76

The point, as I understand it, is that even if these specific vehicles cannot be scaled up to have orbital capabilities (and I think they may well be), they WILL serve as stepping stones to vehicles that WILL have full orbital capabilities. With their suborbital "toys," these firms are building up the knowledge, skills, and technical infrastructure necessary for a real spacegoing capability.

Having multiple private space ventures is the best way for the US to stay in the space game. Why stay in the space game? Because the winners will be the dominant players in the planet's future. The more space-capable players we have, the better off we'll be.

Comment Because, well, it is unrealistic... (Score 1) 574

It might be as simple as the AI saying, "Hey, here's a cool new device I think we should make." It could provide the schematics of a device that would seem to do one thing, but if we're incapable of understanding how the device works, there might be some entirely different purpose.

Vernor Vinge dealt with this topic rather convincingly with the Blight in "A Fire Upon The Deep".

The great stumbling block to any such possibility (aside from the immense improbability of our being able to develop a self-aware machine in the first place) is that we haven't developed computing hardware capable of remaining operational for very long without ongoing maintenance and a reliable supply of electric power. Any AI dependent on these resources would be utterly dependent on human goodwill for its continued existence. Reboot the poor sod and "it's a whole new world for ducks every day." Even the hypothetical Trojan-horse devices suggested by a Blight intelligence would be subject to the same limitations. Not exactly global conquest material.

Comment My favorite Alto application: Mazewar (Score 3, Interesting) 121

In 1977 or thereabouts, I was a co-op student at Xerox' Webster, NY Research Center. At lunchtime, I had access to an Alto, and spent far too much time playing MazeWar, a networked multi-player real-time 3D-perspective game wherein the players navigated a maze (displayed as wireframe 3D with an overhead map at the side), finding other players (who appeared as giant floating eyeballs) and zapping them. Once zapped, you respawned elsewhere in the maze and attempted to sneak up on your opponent and return the favor.

The graphics were extremely simple; there was no detail in the walls, just lines showing the edges, and player positions were limited to the center of each grid square; player movement was in discrete jumps. All of this was done to reduce the computational load for the graphics, of course. As a result, the system was very responsive, and the experience was quite immersive.

Comment Not faked GPUs... (Score 4, Informative) 76

I've read the Heise articles in the original German, and the GPUs were not faked; the cards were an older generation graphics card (~10% of the graphics throughput of the claimed item) with the video BIOS hacked to zero out the card manufacturer ID and the GPU type twiddled to fool the driver into thinking it was the newer card. According to the articles, NVidia is tracing the GPUs through the supply chain by their internal serial numbers.

I would speculate that someone bought up a truckload of obsolete cards, reflashed the BIOS images, and relabeled them with plausible product ID labels. Could have been the Chinese manufacturer, could have been someone elsewhere in the pipeline.

Comment The chilling thing about Ted Unangst's analysis (Score 5, Interesting) 301

As I read his analysis, OpenSSL relies on releasing a buffer, reallocating it, and getting the PREVIOUS contents of that buffer back -- or else it will abort the connection. (Search for the string "On line 1059, we find a call to ssl3_release_read_buffer after we have read the header, which will free the current buffer." in his article referenced by the parent post).

Now, IMO, this goes way beyond sloppy. Releasing a buffer before you're done with it, and relying on a wacky LIFO reallocation scheme giving you back that very same buffer so you can process it, is either 1) an utterly incompetent coding blunder that just happened to work when combined with an utterly terrible, insecure custom allocation scheme, or 2) specifically designed to ensure that this insecure combination is widely deployed to provide a custom-made back door, as it works only with the leaky custom allocator.

If 1), then I must agree with Theo that the OpenSSL team were indeed irresponsible, since at least one of these two cooperating blunders ought to have shown up in a decent security audit of the code, and any decent set of security-oriented coding standards would forbid them both.

If 2), then it was deliberate, and the tinfoil-hat crowd is right for once.

Comment All roads may run ill... (Score 5, Informative) 227

Been there, done that, wondered "What were we thinking?"

In selecting an instrumentation framework for a test system, we went through a careful process of defining what was important, listing the pros and cons of each competing option, ran some tests to see if both would run the instruments we needed, ... Aaaand chose the worse option of the two, as events ultimately showed. The choice was evidence-based, reasonable on the basis of what we knew at the time, and suboptimal. The system worked, but we had to do some ugly stuff to make it work.

Sometimes you just can't outwit Murphy.

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