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Comments

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The Grumpy Programmer has Advice for Young Computer Workers (Video)

dtmos Incredibly wise advice (119 comments)

Robin Miller: But age discrimination in employment, have you encountered?

Bob Pendleton: Oh, absolutely. I got laid off on my 49th birthday and haven’t been able to find a full time job since.

One piece of advice I always give younger engineers and programmers is to be increasingly vigilant about your career as you age. In the last decade or so before retirement one is very vulnerable to layoffs, because one's salary is high and one's formal education was a long time ago.

about a week ago
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Princeton Nuclear Fusion Reactor Will Run Again

dtmos Re:Spherical Torus (147 comments)

Spherical Torus?

I wondered the same thing. However, the National Spherical Torus Experiment web site has this explanation:

The magnetic field in NSTX forms a plasma that is a torus since there is a hole through the center, but where the outer boundary of the plasma is almost spherical in shape, hence the name “spherical torus” or “ST”.

There are also some links to more detailed descriptions.

about a week ago
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NASA Announces Mars 2020 Rover Payload

dtmos Coolest of the lot (109 comments)

Can't decide if the UV laser or the ground radar is the coolest of the lot.

That would be the UV laser. Ground-penetrating radar is so Twentieth Century.

about 1 month ago
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Amazon Announces 'Fire Phone'

dtmos Re:Perhaps not the best name (192 comments)

Yeah, "halt and catch fire" has a new meaning when the device has a lithium battery.

about 2 months ago
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Woods Hole Oceanographic Institution Loses Deep Sea Vehicle

dtmos Columbia River. . . . (93 comments)

Well, if it crossed the Pacific and went upstream the Columbia River, it might have made it to Montana -- although there are a surfeit of dams to overcome along the way.

about 4 months ago
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Star Cluster Ejected From Galaxy At 2,000,000 MPH

dtmos Velocity (133 comments)

Two million miles per hour is less than 0.003c, but still quite a clip, even in astronomical terms.

Since they're discussing velocity (vector speed), and not just speed, the headline is correct in saying " -1000 km/s" when the measured value is -1025 km/s, but one can debate whether the abstract is correct in saying "an extraordinary blueshift of -1025 km/s", rather than "an extraordinary blueshift of 1025 km/s", since "blueshift" gives one the sign of the velocity already.

about 3 months ago
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This 1981 BYTE Magazine Cover Explains Why We're So Bad At Tech Predictions

dtmos Most unlikely technology in 1981: Handheld GPS (276 comments)

I always thought the most unlikely technological development in my lifetime was the handheld GPS device. It would be "most unlikely" because it required tremendous, simultaneous, and largely unforeseen advances in several different technologies, each of which was hard to predict in 1981. The list is at least:

1. Low power, low voltage, low noise L-band receivers, sensitive enough to be compatible with the weak signal coming from the internal antenna of a handheld device;
2. Stupendous amounts of digital signal processing, also at low power and low voltage;
3. Digital map databases of (substantially) every road in the world, accurate to a few meters;
4. A substantially world-wide, wideband wireless data link to get the digital map into the handheld device in the first place;
5. Low power, low voltage, high resolution, multicolor flat panel displays;
6. Gigabytes of low power, low voltage data storage memory; and
7. High energy density, high power density batteries capable of supplying the whole thing.

And, perhaps most impressive of all, the manufacturing technology to make all of the above small enough to fit in a handheld device, at a price low enough to sell by the zillions.

Of the list above, probably only #2 could have been predicted, and then only if one were willing to extrapolate the then-relatively-new Moore's Law by a very large amount. (Recall that Mead and Conway had only written their Introduction to VLSI systems the previous year; until then it was not clear that such complex chips could even be designed on human time scales, let alone built for a profit.)

The fact that a handheld GPS device is now an anachronism, since the technology is now small enough and low-power enough to be integrated into other handheld devices, like smart phones, pleases me no end.

about 5 months ago
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Mathematicians Use Mossberg 500 Pump-Action Shotgun To Calculate Pi

dtmos a bunch of dead zombies (311 comments)

AND a bunch of dead zombies.

What's a dead zombie? Is this some kind of recursion?

(Getting old has a lot of advantages, but one of the disadvantages is that it's harder to keep track of popular memes. I mean, I never understood the whole "vampire" thing, and now we're on to zombies. What's next?)

about 5 months ago
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Data Mining the Web Reveals What Makes Puzzles Hard For Humans

dtmos Re:Idiotic summary (44 comments)

The "they" in the quoted line refers to people, not computers. It's the people picking the method (poorly).

The issue with Sudoku is that easy and difficult puzzles can have the same number of boxes to fill.

about 4 months ago
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Data Mining the Web Reveals What Makes Puzzles Hard For Humans

dtmos Value (44 comments)

Somewhere I read an article by a guy who makes and sells Sudoku puzzles to newspapers. He explained that the value of providing the puzzle was near zero, since anyone with a computer could easily generate thousands of them, and anyone without a computer could get them from any number of sources. The value of his service, and the reason newspapers paid him to provide the puzzle, he said, was that he provided an accurate difficulty estimate to the puzzle. People attempting, and failing to solve, a difficult puzzle rated "easy", and people quickly solving an easy puzzle rated "difficult", were dissatisfied, and complained. People that had the experience they expected -- easy puzzles quickly solved, hard puzzles solved only with difficulty -- were much more satisfied.

The result was, newspaper editors got fewer complaints using his puzzles than they did from his competitors, so they bought from him.

He said he spent far more time tweaking his difficulty-rating algorithm than he did his software that generated the puzzles themselves -- since that was what kept him in business.

about 4 months ago
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One Person Successfully Removed From US No-Fly List

dtmos Older than that (286 comments)

[I]t's actually a very strategic piece of property that dates back to the cold war.

It's actually older than that. The US has been there since the Cuban-American Treaty of 1903.

about 5 months ago
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$30K Worth of Multimeters Must Be Destroyed Because They're Yellow

dtmos Re:Baloney (653 comments)

The fact that there are lots of yellow multimeters for sale in the US is not relevant, for that could mean either (a) they are knockoffs, and Fluke is losing the battle against the counterfeit products; or (b) Fluke has a successful side business licensing its trademark. (n.b.: Multimeters were almost uniformly black -- e.g., the Simpson 260 -- in the years before Fluke introduced its first yellow model, in the 1980s. It was very distinctive at the time.)

And you should exercise caution in what you encourage in others: The issue at hand is a trademark, not a patent, and I think you'll find, if you look up the trademark registration certificate (the controlling legal document), that it very specifically mentions the color yellow.

about 5 months ago
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$30K Worth of Multimeters Must Be Destroyed Because They're Yellow

dtmos Baloney (653 comments)

Any "hobbyist electronics retailer" attempting to sell a multimeter in the US knows -- or should know -- what a Fluke multimeter looks like, and any businessman or businesswoman knows -- or should know -- that there will be problems trying to sell a product that looks like the product with a dominant share of the market.

Also, you don't need "an army of consultants or attorneys to find this information." Trademarks are freely available from the USPTO web site, in searchable form. Anybody can look them up.

Finally, most business contracts between a manufacturer and a distributor will have an indemnification clause, in which the manufacturer warrants that the product has no intellectual property issues and, should a claim be made against the distributor, the costs associated with such claims will be borne by the manufacturer. If Sparkfun's contract for the Fluke knock-offs didn't have such a clause, I'm sure their standard contract will in the future.

about 5 months ago
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The Poor Neglected Gifted Child

dtmos Indeed. (529 comments)

I'm from the same era, and can corroborate nani's experience. Even the football players in my high school -- the guys with scratches on the back of their hands, from dragging them along the ground as they walked -- could name the planets in order.

Of course, since schools were funded by a property tax on the local landowners, the same opportunities were not available to the poorer kids going to the school on the other side of town. The desire was to raise that school to the academic level of the rich school, by spending more on education in general, but what seems to have happened is that the funding was just averaged between them, leading to the poor neglected gifted child syndrome.

about 5 months ago
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NASA Forgets How To Talk To ICE/ISEE-3 Spacecraft

dtmos What, exactly, is missing? (166 comments)

Is it the entire 2 GHz transmitter that is missing? Just the power amplifier? Just the PCM modulator? The feed for the 70m dish?

What, exactly, is missing?

about 6 months ago
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Bugatti 100P Rebuilt: The Plane That Could've Turned the Battle of Britain

dtmos Re:What is "computer-directed flight control"? (353 comments)

they need High voltage AC to heat the plate.

Er, no. They need high voltage DC, not AC, to bias the plate, not heat it. The goal is to encourage electrons emitted from the heated cathode due to the Edison effect (thermionic emission) to travel to the plate, rather than stay in a cloud around the cathode as they would otherwise do. To do this, in typical operation the plate is biased positive with respect to the cathode. The plate only gets heated by the energy of the electrons striking it, an undesirable secondary effect.

about 6 months ago
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Adjusting GPAs: A Statistician's Effort To Tackle Grade Inflation

dtmos Re:Grading by statistics (264 comments)

The IQR (inter-quartile range) would probably be a better measure of spread if you are going to use the median as a measure of center.

To be sure. The difficulty with IQR is that the average college sophomore has no idea what it is. I actually tried this one semester, and ended up having to teach statistics one-by-one to each student that came in complaining about his grade. It was easier, and took less of my time, to use a system that had less technical validity, but used terms with which the students were familiar, and could independently calculate.

I personally prefer that the median correspond to the center of the C range, rather than the top.

Consider it my small concession to grade inflation.

about 7 months ago

Submissions

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Amateur Radio Gets Secondary MF Allocation at WRC-12

dtmos dtmos writes  |  more than 2 years ago

dtmos (447842) writes "The ARRL is reporting that "delegates attending the 2012 World Radiocommunication Conference (WRC-12) in Geneva have approved a new 7-kilohertz-wide secondary allocation between 472-479 kHz for the Amateur Radio Service." This band, below the AM broadcast band, will retain its primary ship-to-shore and radionavigation beacon allocation. Due to the unique propagation characteristics of this part of the spectrum, an allocation has long been desired by the amateur radio community. Much as moonbounce and meteor scatter have produced their own amateur digital communication protocols (OSS under the Gnu GPL, of course), I expect the unique channel impairments of this band will lead to the development of dedicated digital communication schemes (beyond QRSS)."
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Coronal Mass Ejection hits Earth

dtmos dtmos writes  |  more than 2 years ago

dtmos (447842) writes "Spaceweather reports "A coronal mass ejection (CME) hit Earth on Oct. 24th at approximately 1800 UT (2:00 pm EDT). The impact strongly compressed Earth's magnetic field, directly exposing geosynchronous satellites to solar wind plasma, and sparked an intense geomagnetic storm. As night fell over North America, auroras spilled across the Canadian border into the contiguous United States." Aurora were seen as far south as Baileyton, Alabama."
Link to Original Source
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Sports Bars Changing Channels to Video Gamers

dtmos dtmos writes  |  about 3 years ago

dtmos (447842) writes "This summer, 'Starcraft II' has become the newest barroom spectator sport. Fans organize so-called Barcraft events, taking over pubs and bistros from Honolulu to Florida and switching big-screen TV sets to Internet broadcasts of professional game matches.

As they root for their on-screen superstars, "Starcraft" enthusiasts can sow confusion among regular patrons ... But for sports-bar owners, "Starcraft" viewers represent a key new source of revenue from a demographic—self-described geeks—they hadn't attracted before."

Link to Original Source
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DARPA Hypersonic Vehicle Splash Down Confirmed

dtmos dtmos writes  |  about 3 years ago

dtmos (447842) writes "The U.S. Defense Advanced Research Projects Agency (DARPA) has announced that its Falcon Hypersonic Technology Vehicle 2 (HTV-2) flight on Thursday, 11 August, "experienced a flight anomaly post perigee and into the vehicle’s climb. The anomaly prompted the vehicle’s autonomous flight safety system to use the craft’s aerodynamic systems to make a controlled descent and splash down into the ocean."

“According to a preliminary review of the data collected prior to the anomaly encountered by the HTV-2 during its second test flight,” said DARPA Director Regina Dugan, “HTV-2 demonstrated stable aerodynamically controlled Mach 20 hypersonic flight for approximately three minutes. It appears that the engineering changes put into place following the vehicle’s first flight test in April 2010 were effective. We do not yet know the cause of the anomaly for Flight 2.”"

Link to Original Source
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IEEEXtreme 24 Hour Programming Challenge Announced

dtmos dtmos writes  |  more than 4 years ago

dtmos (447842) writes "IEEEXtreme is a global challenge in which teams of student members, supported by an IEEE Student Branch, advised and proctored by an IEEE Member, compete in a 24-hour time span against each other to solve a set of programming problems. IEEEXtreme 4.0 will take place on Saturday 23 October, 2010. Not a student? The IEEE is looking for proctors."
Link to Original Source
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Factorization of a 768-bit RSA modulus

dtmos dtmos writes  |  more than 4 years ago

dtmos (447842) writes "The 768-bit, 232-digit number RSA-768 has been factored. From the introduction:

The number RSA-768 was taken from the now obsolete RSA Challenge list as a representative 768-bit RSA modulus. This result is a record for factoring general integers. Factoring a 1024-bit RSA modulus would be about a thousand times harder, and a 768-bit RSA modulus is several thousands times harder to factor than a 512-bit one. Because the first factorization of a 512-bit RSA modulus was reported only a decade ago it is not unreasonable to expect that 1024-bit RSA moduli can be factored well within the next decade by an academic effort such as ours . . . . Thus, it would be prudent to phase out usage of 1024-bit RSA within the next three to four years.

"

Link to Original Source
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USPTO Asking For Ideas to Enhance Patent Quality

dtmos dtmos writes  |  more than 4 years ago

dtmos (447842) writes "Tired of seeing poor-quality patents issue? Have a great way to solve the problem? Well, here's your chance to be part of the solution. The USPTO has issued a Request for Comments on Enhancement in the Quality of Patents [pdf], seeking public comment on ways to improve "the process for obtaining the best prior art, preparation of the initial application, and examination and prosecution of the application." Comments should be sent to patent_quality_comments@uspto.gov by February 8, 2010."
Link to Original Source

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