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Comment Re:Martian atmosphere - another quibble (Score 1) 229

While I loved the repairing the cracked visor with duct tape scene, I have to say the repairing the blown out hatch with duct tape and polyethylene film stretched credulity to the breaking point.

We are to believe that patch could hold the difference between basically full vacuum and one Earth atmosphere air pressure.
Then why is the rest of the hab apparently made of apparently 3+ inch thick metal / carbon fibre or whatever?

Also, with an open hatch patched with a thick plastic bag, the heating system of the hab wouldn't be able to cope, and also the outside cold would probably render the affixing tape and polyethylene brittle and useless after a short time.

Other than that I agree it was an awesome hard sci-fi movie, with great plot, acting, and science.

Comment Re:The obligation of an engeer (Score 1) 569

What exactly what you be attesting to if you sealed and signed off on your software.

Let's assume your software is reasonably large and complex (non-trivial).

Therefore, it is a given that your software has unknown bugs.

It is a given that you do not know in advance the effect of those unknown bugs on the system that the software will be operating.

Software is just like that.

The only thing I can think of that you would be signing would be that you had gone through:
Some sort of design process
Some sort of design review
Some sort of code review
Some sort (there are many possible sorts and scopes) of testing

Therefore, your non-trivial software will have unknown bugs, of unknown consequence.
Heck, it is probably even theoreticall impossible for you to know if your program will halt, given the inputs it is getting, never mind for you to know what value it will output when/if it 'halt's.

Good thing you didn't sign and seal that your program was correct and safe.

The arbitrary novelty and complexity, and exteme brittleness and fragility, of each unique piece of software, is why software engineering doesn't sign off on its work.
It would be a silly game from the start.

Comment Re:EPA standards (Score 5, Informative) 569

Not condoning the cheating, but there is another issue. Many Americans drive, as their family vehicle as well as work vehicle, "light" trucks (e.g. Dodge RAM 3500) and SUVs which have much larger Diesel engines in them than the ones being discussed in these VW cars.

What I've been told about the structure of the EPA regulations is that driving a much more polluting large Diesel pickup truck as your personal vehicle is allowed, but driving a relatively much more efficient and less polluting small European Diesel vehicle is not allowed.

Something is seriously messed up there.

Comment Re:The information is just dispersed (Score 1) 172

The Kolmogorov-Chaitin definition of random says something to the effect that if there is no process simpler/shorter than the process which produced the sequence/arrangement of events which could predict what that sequence/arrangement of events would have been (and would evolve to next), then the sequence/arrangement is random. It is equivalent to saying that the process which produced the sequence/arrangement is maximally complex.

So if there is a deterministic pattern but it (or its originaing/generating process) is complex enough to be inherently unpredictable, then it is random.

Comment Time should be used in occlusion problem (Score 1) 32

If a series of images is available and observer or target or intermediate objects are moving, occlusion will vary image to image and the nature of the delta portions should be highly informative for recognition. This requires an object/region re-identification subsystem.

Also, scene context statistics should be used, much as preceding utterances are used in speech recognition. Given that we've already recognized a situation type with this that and the other object-type in it in this (possibly dynamic) relation, what are the a priori probabilities for these other types of objects to occur in scene, and assess occluded objects against highest probability objects in situation type. Much more constrained/determined recognition problem in which pieces of objects might suffice to identify them.

Comment The information is just dispersed (Score 2) 172

So when the black hole evaporates by giving off Hawking radiation, who's to say the information (albeit all mixed together) isn't coming out in the particular spatio-temporal pattern of emanation of the radiation?

Sure, the radiation seems (and is effectively to any observer) random, but it is well known that a random bitstring (k-random bitstring) can encode information, and in fact can be the most compact encoding of information.

Random simply means you don't have the means or supplementary information to deduce/detect the pattern. It does not mean that no pattern is there.

Comment Re:Climate trolls consistently misleading (Score 1) 370

Collectively insane, yes.

In denial, not willing to admit we've been destructive idiots, on balance.
Unwilling to be flexible or adaptable at slight cost.

Acting contrary to our best information.

Pretty much insane, or at least, societally addicted to profligate fossil fuel use.

Comment Re:why have countries been increasing their CO2 (Score 1) 370

It's because organized, and particularly democratically organized groups of people seem generally socially incapable of acting on long-term, large-scale threats (threats which are abstract to most individual people.)
See "boiling frog" syndrome.

"I'm not afraid of dying, I just don't want to be there when it happens." -- Woody Allen