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Comment: Re:My B.S. Detector is Going Off (Score 2) 76

by Bruce Perens (#49515639) Attached to: Old Marconi Patent Inspires Tiny New Gigahertz Antenna

If the end of the coil that is hanging is grounded (earthed), it becomes an autotransformer. As it's shown, it's a variable inductor and the disconnected end is irrelevant and has no meaningful physical effect at the frequency a spark transmitter could have reached.

This comment seems to get closer to what they actually mean in their scientific paper. But the article about it is garble and the paper might suffer from second-language issues, and a lack of familiarity with the terms used in RF engineering.

Comment: Re:Hmm, I guess I invented this as well... (Score 1) 76

by Bruce Perens (#49513567) Attached to: Old Marconi Patent Inspires Tiny New Gigahertz Antenna

Damn, I wish I would have patented that and all its quantum magic...

I noticed that my vertical transmitting antenna often works better if I connect a horizontal wire about the same length as the antenna to ground at its base! The wire isn't connected to the transmitting side of the circuit at all! And how well it works varies depending on the length! Obviously there is some deus ex machina at work here...

Comment: Re:My B.S. Detector is Going Off (Score 1) 76

by Bruce Perens (#49513517) Attached to: Old Marconi Patent Inspires Tiny New Gigahertz Antenna

Clearly you missed the bit where they invoked quantum mechanics, surely that explains away all the inaccuracies, like the fact you can already buy chip scale dielectric antennas

The thing that I really hate about Innovation Stories is that the reporter invariably doesn't understand what's going on, and invariably is easily convinced that The Obviiously Very Technical People have some very valuable invention.

Comment: Re:vs. a Falcon 9 (Score 1) 75

by Bruce Perens (#49501071) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

They can carry about 110kg to LEO, compared to the Falcon 9's 13150kg. That's 0.84% of the payload capacity. A launch is estimated to cost $4 900 000, compared to the Falcon 9's $61 200 000. That's 8.01%. That means cost per mass to orbit is nearly an order of magnitude worse.

Yes, this is a really small rocket. If you are a government or some other entity that needs to put something small in orbit right away, the USD$5 Million price might not deter you, even though you could potentially launch a lot of small satellites on a Falcon 9 for less.

And it's a missile affordable by most small countries, if your payload can handle the re-entry on its own. Uh-oh. :-)

Comment: p-value research is misleading almost always (Score 5, Interesting) 208

by SteveWoz (#49495363) Attached to: Social Science Journal 'Bans' Use of p-values

I studied and tutored experimental design and this use of inferential statistics. I even came up with a formula for 1/5 the calculator keystrokes when learning to calculate the p-value manually. Take the standard deviation and mean for each group, then calculate the standard deviation of these means (how different the groups are) divided by the mean of these standard deviations (how wide the groups of data are) and multiply by the square root of n (sample size for each group). But that's off the point. We had 5 papers in our class for psychology majors (I almost graduated in that instead of engineering) that discussed why controlled experiments (using the p-value) should not be published. In each case my knee-jerk reaction was that they didn't like math or didn't understand math and just wanted to 'suppose' answers. But each article attacked the math abuse, by proficient academics at universities who did this sort of research. I came around too. The math is established for random environments but the scientists control every bit of the environment, not to get better results but to detect thing so tiny that they really don't matter. The math lets them misuse the word 'significant' as though there is a strong connection between cause and effect. Yet every environmental restriction (same living arrangements, same diets, same genetic strain of rats, etc) invalidates the result. It's called intrinsic validity (finding it in the experiment) vs. extrinsic validity (applying in real life). You can also find things that are weaker (by the square root of n) by using larger groups. A study can be set up in a way so as to likely find 'something' tiny and get the research prestige, but another study can be set up with different controls that turn out an opposite result. And none apply to real life like reading the results of an entire population living normal lives. You have to study and think quite a while, as I did (even walking the streets around Berkeley to find books on the subject up to 40 years prior) to see that the words "99 percentage significance level" means not a strong effect but more likely one that is so tiny, maybe a part in a million, that you'd never see it in real life.

Comment: Re:You Can See (Score 1) 113

Microminiature accelerometers are really cheap and very very light, and you don't have to wait for them to spin up or deal with their mechanical issues. I doubt you will see a gyro used as a sensor any longer.

Similarly, computers make good active stabilization possible and steering your engine to stabilize is a lot lighter than having to add a big rotating mass.

"But this one goes to eleven." -- Nigel Tufnel