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Developing the First Law of Robotics

jdagius In theory it's nice. In practice it's ... (164 comments)

... never going to work.

One could argue that computer viruses are merely robots without a solid body. So the First Law has already been trashed by all the big powers on the planet.

And who's going to decide what is 'harmful'? Governments again are producing semi-automated robots (drones) which harm people. But that's OK because "it's to prevent an even greater harm" they say. But who decides if 'they' got it right?

3 days ago

Ask Slashdot: What Are the Strangest Features of Various Programming Languages?

jdagius Quirk in MATLAB array syntax (729 comments)

MATLAB was one of the first languages to allow lists of comma-separated numbers between square brackets e.g. [1,2,3,10] to be interpreted as indexed numeric arrays or vectors. A lot of languages do that now, but MATLAB was perhaps the first to do this in 1984. A little-known quirk is that the commas are optional! [1 2 3 10] etc. This was probably introduced as a 'convenience' feature (though typing a space isn't that much faster than typing a comma). But there is a glitch ("feature") in the syntax that interprets space-separated negative numbers differently than you'd expect. So [ 1 2 -3] is interpreted as [1,2-3] (value = [1,-1]) because the precedence of arithmetic operators is higher than list operations.

MATLAB hasn't fixed this 'feature' yet, because it would undoubtedly break a jillion apps around the world. So you must be careful to type [1 2 (-3)] if you are allergic to commas.

BTW it's been fixed by default in OCTAVE, MATLABS free-software clone, but you turn 'quirks' on, if you want to preserve the quirky behavior.

about two weeks ago

Does Learning To Code Outweigh a Degree In Computer Science?

jdagius Does Learning Mechanical Engineering Outweigh ... (546 comments)

... learning to operate a rivet gun or steam shovel? A bridge or building could be more cheaply built by skilled operators with little or no knowledge of stress and strain, but how long would these structures stand?

The same could be said for computer programmers, who may be skilled in coding, but have little or no knowledge of the best methodologies for constructing robust and reliable software systems and structures.

about two weeks ago

Sand-Based Anode Triples Lithium-Ion Battery Performance

jdagius Re:Structure preserving? (60 comments)

@tsa > I don't think it suggests that at all.

Did you read TFA? It says. "In this very simple process, the salt acted as a heat absorber while the magnesium removed oxygen from the quartz, resulting in pure silicon. "

So the article does indeed 'suggest' that Mg is removing O. My question was concerning how is this oxygen removal related to creating porosity. Or not.

In any case, it seems likely that some formerly filled space must be vacated to create porous openings.

Does anyone know how this happens?

about 2 months ago

Sand-Based Anode Triples Lithium-Ion Battery Performance

jdagius Structure preserving? (60 comments)

The article suggests that making nano-scale silicon by using magnesium to remove oxygen solves the usual degrading issues. Why is this? Does the quartz lattice have optimal conduction geometry, which is somehow preserved after the oxygen is removed?

about 2 months ago

"Eskimo Diet" Lacks Support For Better Cardiovascular Health

jdagius Elephant in the room... (166 comments)

... lipid hypothesis
So I get that the "Eskimo Diet" doesn't improve cardiovascular health. But then it doesn't degrade it either. Then why all the "heart smart" low-fat, no-fat, low-cholesterol propaganda we're constantly bombarded with?
It seems Uffe Ravnskov may be right. Dietary cholesterol very likely has little or no bad effects on health. It is probably "good" for you. In fact, statin drugs used to treat CAD are far worse for your health.
Proof: If statins actually were effective against CAD, then the ads on TV could make that claim. If you listen carefully, they don't make any claim that they lower the incidence of CAD. Their sole claim for "effectiveness" is that they lower your blood cholesterol numbers. It would be more compelling if they could claim health benefits of course, but their is no compelling evidence for this.

about 3 months ago

Satellites Providing Internet To the 'Under-Connected'

jdagius Re: In space ... (50 comments)

Objects "in orbit" around the Earth are actually falling freely to the Earth. But thanks to the very large horizontal component in their motion, orbiting objects always overshoot the horizon and thus stay in orbit.
Such objects have no "weight", because weight is defined as, F=mg, a force F exerted by an object with mass m in a gravity field g, resting on a surface preventing the object from falling freely.
The mass of an object is thus independent of gravity, but it's "weight" is just an artifact imposed by surface constraints, and can vary greatly.

about a year ago

Lowest Mass Exoplanet Ever Directly Imaged. Probably.

jdagius Re:Probably pretty cold (43 comments)

> ... sad part ...

No need to be sad. Increasing effective aperture size of the telescope increases its resolving power. The imaging element doesn't have to be a single mirror or lens, but can consist of an array of elements scattered over a large area. Tricky part is getting all of the elements in phase agreement. Also doesn't have to be visible light. We are already 'imaging' surfaces of planets with synthetic aperture radar, operating on the same principle.

So imagine a much larger optical array network, many miles in diameter, for imaging the surfaces of these exoplanets.

about a year ago

Declassified LBJ Tapes Accuse Richard Nixon of Treason

jdagius Sounds familiar... (536 comments)

So ex-VicePresident Nixon communicated with a foreign leadership, telling them to wait after his "re-election" and that he would be more 'flexible' in his dealings with them. Hmm, where have we heard that treasonous trash talk before? :-|

about a year and a half ago

Atlantic Crossing By Amateur Radio High Altitude Balloon

jdagius Re:wikipedia's got the wrong name (51 comments)

> Wikipedia has the name wrong.

No, you are wrong. Bob Bruinga, WB4APR, the inventor of APRS has reverted in the naming convention, and now supports the "_packet_ reporting" moniker because he wants to emphasize that APRS is not just for position reporting. For example, it's extensively used for weather reporting from mostly non-mobile CWOP (Citizen Weather Observers Program) volunteers, who include a lot of non-amateur radio enthusiasts who augment NWS mesolevel forecasts with thousands of home-made stations reporting every ten minutes or so over the Internet. (The ham-radio CWOP volunteers can also report weather via amateur RF frequencies).

Also APRS has been used ("firenet") for reporting brush and forest fires.

more than 2 years ago

Robots Successfully Invent Their Own Language

jdagius No Big Deal (159 comments)

The first humanoid "words" were probably grunted utterances representing names of other humanoids, animals, places and (eventually) events.

Even so, automatically generating unique labels is no big deal for a computer. Every automatic "builder" program already do this. Except they're usually enumerated (i.e. box1,box2, box3, ..., box999), instead of randomly generated ciphers ("xyzzy" etc). But computers don't do anything randomly, it all has to be programmed by a human.

more than 3 years ago

German Military Braces For Peak Oil

jdagius Re:Thorium Reactors people! (764 comments)

>> ... thousands of years of _safe_ operation ...
Completely "safe"? Then how do you explain this paragraph about 'decommissioning' the ORNL test MSR from the article you cited?
"After shutdown the salt was believed to be in long-term safe storage, but beginning in the mid-1980s, there was concern that radioactivity was migrating through the system. Sampling in 1994 revealed concentrations of uranium that created a potential for a nuclear criticality accident, as well as a potentially dangerous build-up of fluorine gas —"

about 4 years ago

Time For Universal Data Plans?

jdagius Internet is free (245 comments)

You already are paying one very low fee to use the Internet: zero dollars.

What you're paying real dollars for is the right to access the Internet by means of various physical carriers: price to be negotiated between carrier and user.

Peronally I prefer the Asok (Dilbert's intern) sewage activated access. Whereever you have a sewer pipe, then you have turdo-charged access!


more than 4 years ago

US Coast Guard Intends To Kill LORAN-C

jdagius Re:hmm (316 comments)

Technology similar to the Omega system is still in operation in Russian, known as "Radiotehnicheskaya Sistema Dal'ney Navigatsii", RSDN-20. In the West it's known by the nickname "Alpha" and is based on a system of three VLF transmitters located in western, middle and eastern Russian. It provides nearly world-wide coverage and is used primarily by the Russian maritime fleet, some using very ancient semi-mechanical receivers still in operation.

If you want to see how these Alpha signal look like, take a peak at this Web Softwarre Defined Radio located in the Netherlands, operating in the VLF band. It is picking up 2 of the 3 stations (Krasnodar and Novosibirsk). They look like long Morse dashes around 11 to 15 kHz frequencies.


more than 4 years ago

Noctilucent Clouds Likely Caused By Shuttle Launches

jdagius FYI, these clouds are in the mesosphere ... (132 comments)

... which is the layer of the atmosphere, 50km-85km, immediately above the statosphere. This is a very lonely place, the air's too thin to float baloons, airplanes and such, and too thick for orbiting spacecraft. Its major inhabitants are falling meteors and rocket ships enroute to outer spaces. Also hosts the D Layer of the ionosphere (during daylight hours) which tends to absorb radio waves transmitted from the ground.
Convection stops in the stratosphere (because there is no temperature inversion there) so very difficult for gases and vapors rising from the ground to reach this desolate place.

more than 5 years ago

The State of Video Game Physics

jdagius Sounds familiar... (170 comments)

>> "... and the Player can come up with solutions to problems that the Designer might not have thought of. "

Maybe the world is just a big game and we're the Players. What would happen if we did not play the game the way the Designer wanted it to played?

Gen 6:5 And GOD saw that the wickedness of man was great in the earth,
and that every imagination of the thoughts of his heart was only evil continually.
Gen 6:6 And it repented the LORD that he had made man on the earth,
and it grieved him at his heart.
Gen 6:7 And the LORD said, I will destroy man whom I have created from the face of the earth;
both man, and beast, and the creeping thing, and the fowls of the air;
for it repenteth me that I have made them.


more than 5 years ago

Methane On Mars May Indicate Living Planet

jdagius Re:Deep Hot Biosphere (200 comments)

OK, Hubbert, not Burton, but the theory originally was based on gelogical availability. Now it's complicated by other factors.

The so-called U.S. peak in the 70's merely signalled a shift to relying on imported oil. Coal production "peaked" too, but no one can argue that we're running out of coal.

My point is that no one seems to be concerned anymore about running out of oil now, whereas Jimmie Carter et al. warned that it was imminent way back in the 70's. If oil came only from squashed ferns and dinosaur remains, we would have run out a long time ago.

... and the demand for oil will continue to rise. No problem, we'll just import it from Mars. :-)

more than 5 years ago



Big Meteor to Strike Earth Tonite

jdagius jdagius writes  |  more than 5 years ago

jdagius writes "Don't panic! The Minor Planet Center at the Smithsonian Astrophysical Observatory is responsible for monitoring the solar system's small planetoids, comets and other space rocks, including those which might be heading our way. They have detected a meteor, several meteors wide, which will impact Earth tonite at 0246 UTC in northern Sudan. No biggie, these kinds of meteors hit the Earth every few months. But this is first one which has been predicted by the MPC and validates the notion that they might catch a bigger one which could cause a lot of damage. This one is expected to burn up harmlessly in the atmosphere, but will nevertheless be equivalent in energy to a small nuclear weapon, roughly a 1 kiloton blast."


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