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Comment: Not distributed (Score 4, Interesting) 63

by Animats (#47962527) Attached to: Researchers Propose a Revocable Identity-Based Encryption Scheme

I'm not qualified to judge whether it's secure, but it's not distributed. "Each user is provided by PKG with a set of private keys corresponding to his/her identity for each node on the path from his/her associated leaf to the root of the tree via a secure channel as in IBE scheme." So there's a tree of all users, maintained by somebody. I think; the paper suffered in translation.

Comment: Re:What has changed? (Score 1) 208

by Animats (#47960005) Attached to: Secret Service Critics Pounce After White House Breach

There was a time that a citizen could walk right up to the White House.

That lasted until WWII.

Until the 1980s, anyone could enter the Pentagon and wander around the corridors. (George C. Marshall, Army Chief of Staff, decided during WWII that there was no way a building with as many people as the Pentagon could keep spies out, and requiring badges would give a false sense of security.) In the 1960s, anyone could enter most Federal buildings in Washington, including the Capitol and all the House/Senate office buildings, without passing any security checkpoints.

Comment: The President was out. The Secret Service did OK. (Score 3, Insightful) 208

by Animats (#47959581) Attached to: Secret Service Critics Pounce After White House Breach

It was a Friday evening. The President had left for Camp David earlier, and his main protective detail went with him. Most staffers had gone home. The guy got just inside the outer doors, where there is a security checkpoint, before he was tackled.

The Secret Service made the right choice not shooting the intruder dead on the lawn. They certainly had the capability to kill him. They would have been heavily criticized, with pictures of the dead body on national TV.

On September 12, a man wearing a Pokemon hat and carrying a stuffed animal jumped the White House fence. He was tackled and arrested. Should he have been killed?

Comment: Re:Comparable? Not really. (Score 4, Informative) 108

by Animats (#47957187) Attached to: Is Alibaba Comparable To a US Company?

When someone buys a share in Apple, they actually get an ownership share in Apple.

Apple, yes. Google or Facebook, no. Google and Facebook have two classes of stock. The class with all the voting rights is in both cases controlled by the founders. The publicly traded shares cannot outvote them, even if someone bought all of them.

Until recently, multiple classes of stock were prohibited for NYSE-listed companies, which tended to discourage doing this. (The classic exception was Ford, which has two classes of stock, the voting shares controlled by the Ford family. This predates that NYSE rule.)

This matters when the insiders make a big mistake and the stock starts going down. There's no way to kick them out.

Comment: Crash not computer-related (Score 5, Informative) 171

by Animats (#47955905) Attached to: Washington DC To Return To Automatic Metro Trains

The Red Line crash was not computer-related. The signalling system for the Washington Metro is a classic electromechanical relay-based system. Just like the New York subways. The Red Line crash was caused by a failure of a track circuit for detecting trains, trackside equipment using an audio-frequency signal sent through the rails and shorted to the other rail by the train's wheels. All those components are pre-computer technology.

As with most railway systems, manual driving isn't enough to prevent collisions, because stopping distances are often longer than visual distances. That was the case here.

The Washington Metro had been sloppy about maintenance of trackside equipment. They do have a central computer system, and it logs what the relay-based signal systems are doing, although it can't override them. They had logs of previous failures, and should have fixed the problem.

Comment: Re:White House (Score 2) 135

by Animats (#47955101) Attached to: Star Wars Producers Want a 'DroneShield' To Prevent Leaks On Set

the US Government use UCAVs to keep the airspace around DC clear.

Actually, the current response to airspace incursions in the DC area is an F-16 and a Coast Guard helicopter. The F-16 is in case it turns out to be hostile, and the Coast Guard helicopter is for the usual case, which is a clueless VFR pilot who needs directions. This happens several times a week. The FAA now insists that all pilots operating within 60 miles of DC (actually 60NM of the DCA VOR) take this online course. Amazingly, there are still clueless pilots wandering into this airspace, although fewer than a few years ago.

Comment: Some info seems bogus (Score 1) 380

by Animats (#47954977) Attached to: Why You Can't Manufacture Like Apple

Some of that info seems bogus. 10,000 CNC mills? Unlikely. 10,000 CNC machines of all types across all of Apple manufacturing, maybe.

There's a nice video about how Apple machines a round can for their round desktop computer. They're going through a lot of steps to make a can, yet they're doing it in a low-volume way. Here's how soft drink cans are made. Same shape, but much higher production volume.

Apple is doing this to justify charging $2700 for an x86-64 machine with midrange specs.

Comment: Re:Google's storage (Score 4, Interesting) 380

by Animats (#47954875) Attached to: Why You Can't Manufacture Like Apple

There are amusing efforts to sell disk drives to Google. Near Google HQ there is a movie theater complex. I once saw an ad run before a movie. Two minutes of sales pitch for bulk purchases of enterprise hard drives, with lots of technical detail. Clearly this was addressed to a very specific audience.

Comment: Re:"Affluent and accomplished" not the criterion (Score 4, Interesting) 177

by Animats (#47947465) Attached to: Netropolitan Is a Facebook For the Affluent, and It's Only $9000 To Join

Frankly speaking, I'm mostly surprised that this doesn't already exist.

It does. There's a Craiglist-type feature on Bloomberg trading info terminals. Yachts, rentals in the Hamptons, that sort of thing. You can message other people via the Bloomberg system if you see something you like.

There's a paid social network for rich conservatives. This is independent, not a Bloomberg thing. It's only $5/month, which is apparently enough to keep the noise level down.

There's a persistent rumor that there are special news sources for rich people. There are, but they're very narrow. There are lots of newsletters you can buy for $50 to $1000 a month that provide detailed coverage of obscure business subjects. If you really need to know what's going on with bulk carrier leasing, oil drilling equipment activity, or wafer fab capacity shortages, there's a newsletter for that. Offshore Alert, which covers offshore scams, is one of the more readable ones, and you can see the first few lines of each story for free. There are expensive newsletters devoted to security and terrorism, which give the illusion of inside information, but they tend to be marketing tools aimed at rich paranoids.

If you want to know what's going on in the world, read The Economist. After you've been reading it for a year, you'll have a good understanding of how the world works.

Comment: Re:Looking for a Job (Score 1) 70

by Animats (#47923925) Attached to: The Case For a Federal Robotics Commission

Is it just me, or does this sound like an ambitious Law Professor looking for a new job as head of a newly minted agency?

Exactly the feeling I got. We don't even have an Federal Internet Commission, and don't seem to need one.

We do need to have the Consumer Product Safety Commission setting safety standards for the Internet of Things. They're properly the lead agency of safety issues. That will probably happen after the first few deaths due to cloud-based control of home devices.

Comment: Re:Of course you use force control to run fast. (Score 2) 90

by Animats (#47920041) Attached to: MIT's Cheetah Robot Runs Untethered

Pardon my ignorant question, but how is it a problem to have traction control? Wouldn't it be enough to glue traction strips to the feet or something?

That's like wearing shoes with golf spikes all the time.

Traction control for feet does roughly the same thing as automotive traction control for cars. The basic idea is to keep the sideways force below the break-loose point. This is the down force on the wheel times the coefficient of friction.

For car wheels, the down force is mostly constant. For a legged robot, it changes throughout the ground contact phase So the side force has to be actively controlled and changed throughout the ground contact. It's also necessary to compensate for leg angle.

Legs have an additional option. If a leg has three joints, you can adjust the angle at which the contact force is applied. This is a big win on hills.

I used to work on this stuff in the mid-1990s, but nobody was interested in building legged robots back then. It could be used for animation, but it was overkill for games. I never expected that DARPA would spend $120 million on BigDog. Robotics projects in the 1990s were tiny.

If you have to ask how much it is, you can't afford it.

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