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Comment: Re:My Face (Score 1) 344

by Pinckney (#35001072) Attached to: Your Face Will Soon Be In Facebook Ads

If you pay for the photograph, it's a work for hire that belongs to you, absent a contract saying something different.

In the US, that is false. See wikipedia for details; essentially there are several criteria that must be satisfied for work by an independent contractor to be work for hire, including in particular that there must be a written agreement between the parties stating that the work is made for hire.

Comment: Re:Is it really too much to ask (Score 4, Insightful) 163

by Pinckney (#34900900) Attached to: Cell Phone Industry's Six Biggest Failed Schemes
I'd really rather if they not do that. If it becomes standard to link to the print version of articles, sites will just remove the print option entirely. As it is, we, who care, get to enjoy these articles in a relatively clean form for minimal work, and the people who don't care effectively subsidise us (thanks!) with their ad impressions.

+ - Backscatter X-Ray Machines Easily Fooled->

Submitted by Pinckney
Pinckney writes: A paper by Leon Kaufman and Joseph W. Carlson in the Journal of Transportation Security asserts that x-ray backscatter machines are not very effective even in their intended role. While carelessly placed contraband will be detected, the machines have glaring blind-spots and have difficulty distinguishing explosives from human tissue. As they write, "It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick pancake [of with beveled edges, taped to the abdomen, would be invisible to this technology... It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible."
Link to Original Source

Comment: Re:Wow ! A house full of hidden explosives .... (Score 1) 424

by Pinckney (#34468768) Attached to: Explosive-Laden California Home To Be Destroyed
The MOVE bombing wasn't even remotely similar. Firstly because it was a row house, i.e. physically connected to the adjacent buildings, secondly because the firefighters at that site did nothing to control the resulting fire, and thirdly because the area was not evacuated prior to the bombing. This is a ranch house, so the fire is unlikely to spread, firefighters are on site to control the resulting fire, and the area will be evacuated.

Comment: Related: POW radio (Score 5, Interesting) 238

by Pinckney (#33968914) Attached to: Building a Telegraph Using Only Stone Age Materials

There is a fascinating account of building a radio in a Japanese POW camp during WWII virtually from scratch.

So we hit upon the idea of taking some tin foil or aluminum foil from the lining of the tea chest from which the Japanese supplied with the rice rations, then by the well known equations for calculating capacity and the relationship of the surface area and spacing of the plates, we built a capacitor or, at least, I built a capacitor which according to calculations should have been about ".01 microfarad."

Comment: Re:This is second place (Score 2, Insightful) 1260

by Pinckney (#33899542) Attached to: Proving 0.999... Is Equal To 1

You are confusing a symbolic representation for a number because the symbol contains numbers in it. It is physically impossible to represent certain numbers using base 10. Pi for example. Is is less obvious, but still a fact that 1/3 and 1/9 are in fact impossible to accurately represent using base 10. The .1111... .33333... and .9999... are all of rather limited accuracy symbols, not numbers, just as if I were to say pi = 3.14159+ The 3.14159+ is a symbol representing Pi, not a number, similarly .9999999... is NOT a number, but is instead a symbolic representation of a number.

.1111... is understood to stand for the supremum of the set {0,1/10,11/100,111/1000...}. See Rudin, "Principles of Mathematical Analysis", page 11. Likewise for .3333..., .999999...., and 3.14159+... where the sets are defined accordingly.

The fact that long division or electronic calculators come up with those results is an indication of human accounting for the limitations of our mathematical symptoms.

Calculators produce such results because they are useful approximations of the supremum.

In base 8, .11111111 = 1/8 + 1/80 + 1/800 + .... That number, multiplied by 7 becomes .77777777777... or 7/8 + 7/80 + 7/800 +... You can use the same bad math you used earlier to prove that 1 = .7777777... base 8 that you used to claim that 1 = .99999 in base 10

Here you are in error. 7*.111111...= 7*(1/8+1/8^2+1/8^3+...) = 7/8 + 7/8^2 + 7/8^3 + ... = (7/8)/(1-1/8) = 1; the reduction from an infinite geometric series to 7/8/(1-1/8) is a common result from any high-school algebra course.

Note in particular that 7/8+7/80+7/800+... is not equal to 1.

Comment: Make your own. (Score 4, Insightful) 524

by Pinckney (#33778354) Attached to: US Says Plane Finder App Threatens Security

"Anything that makes it easier for our enemies to find targets is madness. The Government must look at outlawing the marketing of such equipment."

Perhaps they should consider banning the ADS-B transmitters, then?

In any case, banning the app would do nothing to anyone with the funds for a SAM. See this document to make your own reciever.

Comment: Misleading summary (Score 4, Informative) 126

by Pinckney (#33639214) Attached to: Designing Wireless Sensors To Be Dropped Into Volcanoes

According to Horsfall and his fellow nails-tough tech developers, their carbide electronics can keep working up to temperatures of 900C. This is actually sufficient to withstand immersion in some lavas/magmas, though by no means all. In any case it's difficult to see how any wireless signal could be transmitted through molten minerals, so presumably the inventors are talking more about locating their kit in places within a caldera which - although extremely hot - are not enough so to actually melt rock.

The caldera is not a synonym for lava puddles. They're talking about putting a sensor in the caldera where it can detect gasses. It's not likely to be floating, much less submerged, and in fact that would presumably interfere with the mission of detecting various gasses.

(I've only read the article, not the papers)

Comment: I played it only last year... (Score 1) 362

by Pinckney (#33199608) Attached to: Gamer Plays <em>Doom</em> For the First Time

I played it for the first time only last year, and was pleasantly surprised. The controls are perfect. I felt like the shareware Episode I was most enjoyable, perhaps because I was reluctant to use the plasma and rocket weapons when they became available. The later episodes also seemed to involve me getting hemmed in more often.

Personally, I prefer Doom: The Roguelike overall, but Doom is still a fine, if ugly, shooter.

Comment: Not necessarily forced (Score 2, Informative) 423

by Pinckney (#32314480) Attached to: IBM's Patent-Pending Traffic Lights Stop Car Engines

Upon receiving the stop-engine notification, the vehicles may automatically switch off the engine, or display an alert informing drivers to manually switch off the engines. A vehicle may optionally notify the service once its engine is switched off.

For all of you concerned about not having complete control.

The summary doesn't effectively explain when this would be useful. At most lights, it won't matter. The example the patent gives is a 2 minute light, for which it is inefficient to restart the engine state. It suggests "waiting for 10 minutes for a railway to clear" as a case where this would be useful.

The patent seems very vague. It talks about processing information about the movement about other cars, doesn't comment on what should be looked for, how that information is to be determined, or how wait-time should be estimated. It basically seems to be a patent for the idea of signaling the car when a long wait is anticipated.

Comment: Re:Great step forward (Score 2, Informative) 252

by Pinckney (#32313718) Attached to: Air Force Sets Date To Fly Mach-6 Scramjet

Again, horozontal Gs (e.g. normal to the spine). Fighter pilots experience vertical Gs (parallel to the spine). From wikipedia "Early experiments showed that untrained humans were able to tolerate 17 g eyeballs-in (compared to 12 g eyeballs-out) for several minutes without loss of consciousness or apparent long-term harm."

You might want to take a look at the Gloster Meteor F8 Prone Pilot, an experiment to control a plane from a prone position to better cope with Gs.

Comment: Cargo pants are nice. (Score 1) 763

by Pinckney (#32118646) Attached to: How Do You Handle Your Keys?

Do you really need all those keys on you? It seems to me that the *three* keys for your girlfriend's place are probably somewhat redundant. Maybe they're front/back/basement keys, in which case you probably need only one unless you're living there. Your roof key can probably be stashed at home.

Cargo pants are really nice, if you can wear them. In general, keyfobs aren't worth the hassle. If you need what they have--the SAK, for instance--take them off the keychain and carry them either in your pack, which you apparently have with you most of the time, or in some other pocket. Though the later doesn't reduce the total volume of hardware, it does spread it out, and is thus much more comfortable.

"If people are good only because they fear punishment, and hope for reward, then we are a sorry lot indeed." -- Albert Einstein