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Comment: I thought the point of the charge ... (Score 3, Interesting) 35

by Ungrounded Lightning (#48929295) Attached to: Spider Spins Electrically Charged Silk

I thought the point of the charge was to make the "wooly" side-fibers of the strands wrap around the prey's limbs and/or the microscopic irregularities in the exoskeleton, tangling to it. "Tying" the fibers to the prey would have a similar binding effect to gluing them to it, without the need for glue, and lots of little fibers could make a very strong attachment.

(Stretching fibers made of long chains makes them stronger by aligning the chains along the direction of the stretch.)

Comment: Also: lots of code has been vetted for decades (Score 1) 46

Why are they still using C to deal with network protocol? Is the performance so critical that it's worth all the troubles?

Also, because there's a lot of C code that has been in heavy use, and tested for correctness, for decades, suitable for reuse with substantial confidence that it's correct (though you check it anyhow...).

Let's see you find code like THAT for a language that hasn't been AROUND for decades. B-)

Comment: For starters, because it's transparent. (Score 1) 46

Why are they still using C to deal with network protocol?

For starters, because it's transparent. The "K&R compliant assembly laguage", as one of my former colleagues once characterized it, translates to object in a clearly understandable way (especially if you turn optimization down or off). Though it gives you more opportunities to create bugs, it makes it hard for the bugs to hide from inspection.

The "higher-level" the language, the more it takes over and inserts its own stuff between you and the metal, and the more opportunity for that to inject an invisible vulnerability - which you might have trouble removing even if you DO discover it.

Meanwhile, many of the things "higher-level" languages protect you from can also be detected and flagged by both modern C compilers and code examination tools - starting with the venerable "lint".

Comment: Re:CA requires commercial licenses for pickup truc (Score 1) 208

I can guarantee you that if the Govt. left it up to drivers to get the proper training and instruction on how to operate vehicles safely, people wouldn't do it.

Interesting claim - since it doen't work that way for guns.

Where the government requires training, most gun purchasers take the minimum required, then stop. Where it doesn't, most people start with the course recommended by the gun stores (which is far more comprehensive - and more focussed, with less time spent on political indoctrination B-) ) and also do substantially more range time, until they feel adequately competent. (Then there are those that get interested in shooting as a hobby...)

A similar effect is the reason police normally don't shoot at private ranges simultaneously with civilians. Most police are embarrassingly HORRIBLE shots and pistol-handlers - because they do only the minimum training and practice required by the department (which has lots of other stuff for them to do while they're being paid for their time), and almost never have to actually fire their gun during their work.

Comment: Re:Frickin' Lasers! (Score 1) 234

by prisoner-of-enigma (#48925075) Attached to: White House Drone Incident Exposes Key Security Gap

You can get around this by using an array of lasers, each of which is individually rather harmless, but focused together would be enough to destroy such a target. The "danger area" would be restricted to the focal point. Anything outside/beyond/inside that point would receive much less laser power and likely escape damage.

Now if your drone is using active terrain masking, that makes it more difficult to hit at range. However, such a system would probably require a human remotely controlling it, making that susceptible to jamming. I don't think automated terrain avoidance (in real time) is practical just yet for anything a non-military entity could get its hands on. And in any event, such a terrain-avoidance system would likely need its own sensors (radar/lidar) which could be detected, jammed, or both.

Comment: Re:Stronger regs ? Try a better radar (Score 1) 234

by prisoner-of-enigma (#48924983) Attached to: White House Drone Incident Exposes Key Security Gap

If you shield a drone it becomes heavier and then needs to be bigger. Also at that point the drone needs to either be self guiding or have a communication/control system that won't be knocked out. You get the old little more weight little more propulsion to carry the weight cycle going and all of a sudden your drone isn't small anymore.

So what's your point? That a more capable drone is also bigger? So? So what? That's obvious. Do you think the added size/complexity of such a thing would be any impediment whatsoever to a determined aggressor? If you want to penetrate controlled airspace to do something nefarious, you're perforce going to want something that's difficult to detect, difficult to jam, difficult to shoot down, and has enough payload to carry whatever you need to cause the damage you're looking for.

That seems an incredibly strong statement. So strong that it looks like it doesn't have enough thought behind it.

Really? Then let's hear your alternative options. I already covered sensors and weapons, but let's recap. Radar is vulnerable to stealth, so it won't do the job alone. Lidar is too short ranged to do the job alone. Acoustic is even worse. But put together, a web of such sensors would be very difficult to overcome. If there are other sensors out there that are even remotely applicable, please enumerate them.

As for weapons, you have only three options: ballistic, missiles, or directed-energy weapons. Ballistic weapons have all kinds of downsides, from trajectory computation to wind to limited ammo, not to mention the inevitable collateral damage from misses (of which there will be MANY). Missiles have similar downsides. DEW's have (almost) none of these, the sole one being the potential for (minor) collateral damage in the case of a miss. You could even potentially mitigate this by using an array of low-power lasers, individually almost benign, but focused together to take down a drone.

Comment: Re:radar would have no problem distinguishing quad (Score 1) 234

by prisoner-of-enigma (#48924865) Attached to: White House Drone Incident Exposes Key Security Gap

This assumes you can get a good doppler signature on the rotors at all. I'm not an expert on radar/stealth construction, but I know a fair bit about it. A rotor made of radar-transparent (or absorbent) material would make it rather hard to detect, at least until it was well within range to do damage.

Comment: Re:CA requires commercial licenses for pickup truc (Score 1) 208

Ford F150 Lariat.

For the 5 1/2 ton towing capacity (which also translates to "won't blow the engine head gasket towing a loaded trailer up CA 88 like the van did" - turns out they designed that vehicle's engine with the cylinders too close together so this one pair had a very thin piece of gasket between them,..).

(No time to get the GVR before I have to get to work...)

You know, the difference between this company and the Titanic is that the Titanic had paying customers.