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Comment Mysterious "Aurora" attack not so mysterious. (Score 1) 50

There's nothing mysterious about this. The problem is that if someone gets control of circuit breakers for large rotating equipment, they may be able to disconnect it, let it get out of sync, and reconnect it. This causes huge stresses on motor and generator windings and may damage larger equipment. This is a classic problem in AC electrical systems. A more technical analysis of the Aurora vulnerability is here.

The attack involves taking over control of a power breaker in the transmission system, one that isn't protected by a device that checks for an in-phase condition. Breakers that are intended to be used during synchronization (such as the ones nearest generators) have such protections, but not all breakers do.

Protective relaying in power systems is complicated, because big transient events occur now and then. A lightning strike is a normal event in transmission systems. The system can tolerate many disruptive events, and you don't want to shut everything down and go to full blackout because the fault detection is overly sensitive. A big inductive load joining the grid looks much like an Aurora attack for the first few cycle or two.

There's a problem with someone reprogramming the setpoints on protective relays. This is the classic "let's make it remotely updatable" problem. It's so much easier today to make things remotely updatable than to send someone to adjust a setting. The Aurora attack requires some of this. There's a lot to be said for hard-wired limits that can't be updated remotely, such as "reclosing beyond 20 degrees of phase error is not allowed, no matter what parameters are downloaded."

Comment Web programming sucks. (Score 1) 608

Ignoring the racist whining, he has a point. Web programming really sucks. Even web design sucks.

HTML started as a straightforward declarative layout language. Remember Dreamweaver? Macromedia's WYSIWYG editor for web pages. It was like using a word processor. You laid out a page, and it generated the page in HTML. It understood HTML, and you could read the page back in and edit it. Very straightforward. You didn't even have to look at the HTML. Back then, Netscape Navigator came with an HTML editor, too.

Then came CSS. DIV with float and clear as a primary formatting tool (a 1D concept and a huge step backwards from 2D tables), Javascript to patch the formatting problems of CSS, absolute positioning, Javascript to manage absolute positioning... The reaction to this mess was to layer "content management systems" on top of HTML, introducing another level of complexity and security holes. (Wordpress template attacks...)

It's as bad, if not worse, on the back end. No need to go into the details.

All this is being dumped on programmers, with the demand for "full-stack developers" who understand all the layers. Cheap full-stack developers. Usually for rather banal web sites.

Not only is this stuff unreasonably hard, it's boring. It's a turn-off for anyone with a life.

Comment Being a quant in the early years. (Score 4, Interesting) 96

His fund has an impressive trading record. He had the big advantage of starting early, in 1982, when almost nobody was doing automated trading or using advanced statistical methods. Their best years were 1982-1999. Now everybody grinds on vast amounts of data, and it's much tougher to find an edge. Performance for the last few years has been very poor, below the S&P 500. That's before fees.

The fees on his funds are insane. 5% of capital each year, and 45% of profits. Most hedge funds charge 2% and 20%, and even that's starting to slip due to competitive pressure.

Simons retired in 2009. You have to know when to quit.

Comment Re:What happened to Scheme? (Score 1) 415

Abelson and Sussman is a delightful book for programming theorists. Scheme is a big improvement over Common LISP. Learning Scheme from Abelson and Sussman is straightforward for people who can get into MIT.

This is not most of the programming population. As someone else pointed out, programming today is mostly the creation of glue code to tie together a number of (usually buggy) components. Neither the webcrap crowd nor the appcrap crowd needs Scheme. In fact, if you have that strong a theoretical background, you tend to overdesign simple programs.

Comment Good idea (Score 5, Insightful) 415

Python isn't a bad first language. It has all the important advanced concepts - objects, dictionaries, closures, and threads. The syntax is reasonable. Some people are bothered by the forced indentation, but for new programmers, it will seem natural.

Most of the problems with Python are performance related. They come from obscure features of the language, such as the ability to do "getattr" and "setattr" on almost anything, including objects running in another thread. So everything has to be a dictionary. (This is sometimes called the Guido von Rossum Memorial Boat Anchor.) PyPy is struggling hard to overcome that, with some success. (The optimization approach is "oh, no, program did Obscure Awful Thing which could invalidate running code" - abandon compiled JIT code, shift to backup interpreter, flush JIT code cache, execute Obscure Awful Thing, wait for control to leave area of Obscure Awful Thing while in backup interpreter, rerun JIT compiler, resume running compiled code.)

Comment Re:OMG, not my tooth brushing!!! (Score 1) 150

...There are two sides to that. How would you like an option to buy dental insurance that is dramatically cheaper, but which you can only get if you allow your brushing habits to be monitored and corrected? ...

Already being done for car insurance if you allow a monitoring device to plug into your car's computer port.

We do need to draw a line that prevents preferential treatment based on characteristics which are not within the control of the individual, including past behaviors, but I see no problem and lots of advantages in enabling the use of pricing to encourage behavior that reduces costs.

In general (but not complete) agreement. I still have a significant privacy concern regarding how else any data are used by ~third parties affiliated with the data collector~ (as many privacy policies word it).

Comment Re:OMG, not my tooth brushing!!! (Score 4, Insightful) 150

... If somebody learns every detail of the motions I make when I brush my teeth...

While your comment sounds like over-the-top sarcasm, keep in mind the time when you go to the dentist and your dental insurance company refuses to pay their portion of the bill because you have not been brushing your teeth properly....

Comment Re:Incoming international flights (Score 1) 702

Yeah, no. You can't enumerate every permutation of every weapon imaginable. At some point, you have to expect an adult to assess a new situation using generally acceptable principals to reach a reasonable conclusion.

Ask a random guy on the street whether Scala is a declarative language and you should expect a random distribution. Ask him whether a disassembled rifle is a weapon and you should expect a solid "yes". You shouldn't need to train on that.

Also, this guy was a dumbass.

Comment Re:Power? We dont need no stink'n power! (Score 1) 468

Autoland has been a thing since the early 70s. The first aircraft to have it, the Hawker Siddeley Trident 3 (an aircraft similar to the Boeing 727 in layout - three engines at the back of the aircraft and T-tailed) was flying autolandings in pretty much zero visibility decades ago.

Comment Re:Power? We dont need no stink'n power! (Score 1) 468

Since all modern large airliners are fly by wire, you're screwed anyway.

Airliners have multiple redundant power buses. Each engine has a generator, and there is also an APU (auxilliary power unit) which has a generator. If all three fail (for example, because the plane ran out of fuel, it's happened, or flies through a flock of Canada geese and loses all engines and for some reason the APU won't start) there is a ram air turbine that sticks out into the airflow and powers a generator. There is also a mandated amount of reserve battery power. Talking of losing all engine power, the Airbus A320 that went in the Hudson has purely electronic controls, and remained controllable after a double engine failure.

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