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Comment Re:I can juggle three ... (Score 1) 59

I usually begin a session by telling my student that it's only gonna take 10 minutes.

Instead of the success stories, I would be more interested in how many students are like me and the guy I replied to: hours and hours of practicing to get anywhere.

Mind you, people like me are also behind the rest in dance classes, car driving (with stick shift and Dutch bicyclists everywhere) and everything else that requires motoric coordination skills.

Comment Re:I can juggle three ... (Score 1) 59

It took an hour a day for a solid month before I could juggle three balls at all.

Sounds familiar. Then I met a woman (who ended up becoming my wife) and explained her the basics and within twenty minutes she was able to keep three balls in the air for ten throws or so.

That day, I decided to restrict myself to practicing skils that I actually have some talent for. :-)

Comment Re:In a good way, balancing diameter (Score 3, Informative) 94

"From TFA, the changing cross srction reduces resistance as it stretches. ... they could be designed for no change when stretched"

Well, that's not quite what TFA writes: "As expected, electrical measurements show that the fibers increase resistance as the fiber elongates and the cross sectional area narrows. Fibers with large diameters (~600 [micrometers]) change from a triangular to a more circular cross-section during stretching, which has the appeal of lowering the resistance below that predicted by theory."

The abstract doesn't mention how the circular/triangular transition would affect the resistance - with conservation of volume it shouldn't matter. But I don't read here in any way that this effect would be able to cancel the resistance increase due to stretching.

Note that in first approximation, resistance would scale as L^2 for a wire with length L (both diameter decrease and length increase affect the resistance). With stretching up to a factor 10, i.e. 100x increase in resistance, a small effect due to the shape of the cross section would be negligible.

Submission + - EU fines TV makers for 1.47 billion euro (europa.eu)

hankwang writes: The European commission fined a number manufacturers for pricing fixing of cathode ray tubes in the period between 1996 and 2005. The total fine was EUR 1.47 billion (USD 1.92 billion), for Philips, LG Electronics, Samsung SDI, and three other firms. According to the European Commission: "For almost 10 years, the cartelists carried out the most harmful anti-competitive practices including price fixing, market sharing, customer allocation, capacity and output coordination and exchanges of commercial sensitive information. The cartelists also monitored the implementation, including auditing compliance with the capacity restrictions by plant visits in the case of the computer monitor tubes cartel. "

Other news sources:

Comment Re:Hey Slashdot Editor! (Score 4, Insightful) 341

"Coal spews more radiation than a nuclear meltdown"

I'd like to see a source for that. More radiation than a properly functioning nuclear plant, maybe. But accidents like Chernobyl or Fukushima: no way!

Plus: the radioactivity released by coal plants is mostly in the fly ash, which is filtered out in modern plants. So it's essentially comparing near zero amounts of radioactivity.

Comment Re:Still shitty consumer protections (Score 1) 148

Self-reply: the Dutch version actually has a link to the T&C, at http://www.cleafs.nl/publisher-registratie.html :

Rough translation of section VIII: The publisher is not allowed to [generate artificial traffic]. In case of a violation, the publisher is instantaneously and without warning subject to a fine of EUR 50,000 plus EUR 500 for every additional day of violation.

Comment Re:Still shitty consumer protections (Score 1) 148

a website could put in T&Cs ... terms for $1,000,000 per day penalty for late payment on an account worth $10,000 in it's total life.

In 2008, I got an email inviting me to participate in an affiliate network. I was curious, but the T&C indeed had a statement along the lines of "if you generate invalid clicks, as judged solely by us, you will be obliged to pay EUR 50,000 fine". I wonder what would have happened if I had done business with them. As a business-to-business deal, consumer protection laws would probably not have applied there.

The website still exists: http://www.cleafs.com/ ; they are still fishy: there is a form to apply as a publisher, with a checkbox for accepting the T&C, but no link to the T&C.

Comment Re:You can have 2: cheap, realtime, or resolution. (Score 1) 549

An analog filter doesn't peek ahead either, and is therefore limited in what it can do. But such a limited analog filter should be trivial to simulate as a digital no-peak-ahead filter.

Give me one example of something that can be done with an analog filter which is not trivial to simulate in a zero-delay streaming digital filter.

Comment Re:You can have 2: cheap, realtime, or resolution. (Score 1) 549

"all of the cheap ways to do digital signal processing add intolerable amounts of latency, so hearing aids are stuck with hybrid analog+digital designs"

I don't see what kind of analog filter circuits would would be so difficult to simulate digitally with more than 1 sample of latency. An analog filter is essentially a network of components that subtract, add, multiply, and accumulate voltages. That's trivial to do with a low end dsp which acts on a digital stream and has a couple of bytes storage.

Comment Re:The iPhone effect? (Score 1) 280

"I have three spare batteries (ie 4 batteries) to make damn sure I can use it!"

I used to carry a spare with my previous phone, but I found it a pain to keep track of which one needs charging. Plus, you need to power cycle the phone both to switch batteries and to recharge the spare, which is annoyingly slow on a smartphone.

Nowadays I carry a usb cable to charge my phone from my laptop, and a Duracell portable recharger in case I don't have a laptop around. The portable charger is good for about 2/3 recharge of the built in battery of my htc Desire S.

Comment Re:So how really do they account for the swirling (Score 1) 105

According to TFA they didn't account for Coriolis effects. The overall rotation causes 60 pixels of shift per hour, whereas the differences in rotation speed are only good for 3 pixels per hour.

I don't know much about hydrodynamics of gas giants, but I suppose that there is a mechanism that prevents the formation of hurricane-like structures that are big enough and rotating fast enough to show up on photos of this resolution. Typical photos of Jupiter show only small scale eddies. Except for Jupiter's big spot, but even that one doesn't change shape on a timescale of a few hours.

Comment Re:Did the signal degrade, or the noise increase? (Score 2) 615

"make your router and computers with directional antennas so your gear can just ignore interference. using a phased array antenna"

I've built improvised directional antennas for wifi routers out of cardboard, paper, and aluminum foil. Bend a sheet of aluminum foil on paper (25x15 cm will do) into a curved shape and mount it on the router antenna. Convenient if placing the router in the center of the house is impractical. Because the wavelength is 12 cm at 2.4 GHz it won't generate a tighly focused beam, but it will help reducing interference with transmitters behind the reflector and boost the signal in front.

See e.g. here for inspiration.

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