Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. ×

Comment Re:Too good to be true. (Score 1) 174

Not in the sense of a mirror, but yes, it does, nondirectionally. More importanty, it tends to radiate at frequencies not absorbed by the material.

Look, "reflection" is a specific concept, OK? It's a different thing than absorption and emission. They are two different effects, which is why we use different words to describe them. There is some refraction by clouds, and I'm sure some trivial percentage is refracted multiple times to end up headed back towards the surface, but that's about it.

Why does the distinction matter? Actual reflection of IR nearly blocks radiative cooling (at some point the reflective surface, not being perfect, heats up and starts radiating). This is why a really good thermos needs a reflective layer in addition to a vacuum gap. If IR were being reflected close to the emitter, which it's not, changing the frequency to one not reflected would make a huge difference.

Absorption is very different. Sure, the atmosphere absorbs IR and becomes warmer as a result, but it's not like that happens meaningfully within a few yards of the ground! Changing the frequency of your thermal radiation a bit will not make a meaningful difference in cooling. OTOH, covering something sitting in the sun with a reflective surface makes a significant difference.

Comment Re:/. editors: why do you maintain this shit hole? (Score 1) 921

That's the natural result when you tell yourself a story where a politician is essentially a comic book supervillain. There's no room to coexist with others who don't believe the story. They're all dupes or sheep or collaborators in supervillainy, and the world around you seems to be filled with darkness.

The way out is to stop telling yourself scary stories and try to objectively, dispassionately observe the facts and events.

Comment Re:No (Score 1) 114

Technology is extremely brittle.

And yet it has never gone backwards.

If the power grid were down for two weeks, society would devolve into barbarian survival fighting.

In some of the cities, perhaps. People will riot over anything. But there are a lot of "preppers" out there who would take 2 weeks just to stop patting themselves on the back. Power would be restored and the military would restore order.

large a population wanting too much energy, generating too much pollution for the balloon to keep inflating forever

Pollution in the US has fallen dramatically in my lifetime. The same will eventually happen in China and India as they become fully industrialized; heck, there's already some movement in China.

. It is now beyond obvious that individual greed will prevent humans from doing anything about this because it is not profitable to a few individuals

Human nature hasn't changed ever, but here we are, with centuries of amazing scientific and technological advancement.

Comment Re:You don't own common sense (Score 1) 921

So when one is presented with a model that works better then ones own one shouldnt try to emulate the more effective model?

A culture isn't "one", a culture is "many". Cultures don't try things, individuals do. I don't get to decide what the culture does. You don't either. The culture does what it does.

If you don't like it, go ahead and say so and see if it helps. I don't think it will help. One new aspect of the US culture is that we collectively seem to be about done listening to lectures from people who don't like us.

Comment Re:Should have listened (Score 1) 921

Unless you are a native american, you should be packing too.

Why? "Native Americans" were conquered. So where those that conquered them until we have the US. There should be none of this nation within a nation crap either. It's all United States.

Now if someone wants to come here, we allow that. They need to do it legally and they need to assimilate. Muhammadists aren't doing that. They set up enclaves and no go zones in Europe as well as the US. They have absolutely no interest in US law, just sharia law and they'll even tell you that. They think we have to bend to what they want. Screw them, they need to go back to where they can practice their sharia law and honor a man that was really nothing more than a thug and a pedophile. We are experiencing an invasion just as they said they would do.

Comment Sha-1, what about md5? (Score 1) 185

I still get a bunch of back talk by people that insist we still use MD5. Something that has been broken for almost a decade. Sometimes we have to, like when dealing with Microsoft servers. They still have to use MD5 because Microsoft doesn't care about security. They even recommend turning off FIPS because they say there are better algorithms and such... that they DON'T EVEN OFFER! So you're using stuff that isn't even FIPS. Often that's an export grade or you can break it in real time encryption.

Don't understand, why not just say -OK and fix it right now?

Comment Re:I'd be happy to work for local airports (Score 1) 47

You have no idea just how absurd what you're saying is. Airports are big. I mean really big. Even the smallest airport I've been to is big. It's very unlikely you'd ever be able to get close enough for bird shot to do anything. If a drone is in your backyard - yea, you have a chance. Airport - we'd be laughing at you.

Might be good for a weight loss program, however.

Comment Re:Too good to be true. (Score 3, Informative) 174

Outer space is at ~3K/-270C: having that as your cold sink *day and night* is really quite significant.

Radiative cooling doesn't work that way: all that matters is your temperature. You don't radiate more into a cold area than a hot (a hot area sends more thermal radiation to warm you up, but that's orthogonal). It would be different if the atmosphere reflected IR, but that's not the case.

Comment Re:Using SHA-1 in this day and age is just lazy (Score 1) 185

It's arguably a major Bug in Git if the Git software keeps track of an object Solely by Hash, and lazily assumes that the Hash uniquely identifies a specific version of the file,

A hash of 128 bits or more is a more reliable unique ID than anything custom you could code up. Safe vs malicious attackers is different, and as others have pointed out, sign your commits. But as just a way to get a reliably unique ID for a document (or set thereof)? It's a very solid approach.

Comment Re:He's just a populist, it's just rhetoric! (Score 1) 921

Unfortunately guys like Trump really do embolden people and cause an increase in hate crime.

Massive increase in hate crime, all right. Let's see. We have one (1) murder confirmed by a drunkard since The Donald got to be The Pres.

On average, we have somewhere around 750 murders nationwide in any given month. and ONE (1) of them attributed to "hate" (presumably, the rest of them were just "extreme dislike"?). So, 0.14% increase in murder due to "hate crimes" since The Donald got to be The Pres....

Somehow, I can't find it in myself to see a massive epidemic in "hate crimes" in a drunkard doing something stupid....

Slashdot Top Deals

"There... I've run rings 'round you logically" -- Monty Python's Flying Circus

Working...