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Comment Re:Calculations (Score 3, Informative) 93

They're talking about the theoretical strength of SWNTs, which is upwards of 120GPa. But the highest ever measured SWNT strength, last I read, was around 60Ga - and that's the properties of individual tubes (ropes don't even approach it).

Whenever you're reading something and it mentions needing a "carbon nanotube tether", toss whatever you're reading in the "sci-fi" category. Not even the hard sci-fi category. And all for what - a ~6 year Pluto transit time? Lame.

Don't they have anything better to research?

Heck, even I can think of a more plausible approach than that - one that doesn't require unobtanium at least. Forget the "diamond anchor", land a microsat on it (approaching comet, not a retreating one). Yeah, that takes a lot of delta-V, but if it's just a microsatellite, then that's not a lot of mass. Then, forget about the "carbon nanotube tether"; use a space fountain between the large craft and the lander. Space fountains (such as paired coilguns, for example) are plausible with today's technology, requiring no unobtainium.

But the whole concept of delta-V from a comet is just not a worthwhile avenue to pursue either way. Way too much difficulty and mechanisms for failure for way too little reward.

Comment Re:Does Sony also provide... (Score 3, Informative) 115

20/20 vision is defined by the ability to resolve 1 arc minute. For example, the "E" on an eye doctor's chart on the 20/20 vision line is 5 arc minutes tall, as reading it takes the ability to break it down into five vertical glyphs and distingish between them. That page is based on the premise of a person being able to resolve 0,3 arc minutes.

Problem.

Also, see above. The human eye has a lot more limitations than just a simple single angular resolution figure can express. I even forgot to list one: time. Not only does motion greatly limit one's resolution ability, but even on a stationary image, the person has to be able to focus and take time in order to get even "normal" levels of visual acuity.

Comment Re:Does Sony also provide... (Score 5, Informative) 115

The maximum physically possible resolution for the human eye to see is 2190 dpi. But that's not an average eye, but rather a flawless eye limited only by the size of the pupil; and viewed from as close as an adult can focus, 4 inches.

If we downgrade from a perfect eye to an average eye, the resolution drops down to 876 dpi... but still at 4 inches.

At a more practical 12 inches, this drops to around 300 dpi. Which is why magazines are printed at 300 dpi - it's good enough for most practical circumstances.

Also note some additional limitations:

  * These sort of resolution figures are based on the ability to distingish bright white lines from bright black lines without them blurring together into gray. The smaller the contrast and the dimmer the light, the less the eye can resolve.
  * The human eye also loses a great deal of ability to make out resolution when objects are moving.
  * Obviously the further away one is from the center of the field of view, the lower the resolution - with a rather fast dropoff.

Yes, 808 dpi is complete and total overkill, unless you've got superb eyes and are in the habit of holding your phone as close to them as you can focus while looking at high contrast stationary images.

Comment Re:And? (Score 1) 205

A lot of things come at no cost though. I find it amazing how many people for example will spend a fortune on their graphics card, motherboard, processor, ram, hard drives, etc... but then run it with a cheapo power supply.

Let's say that you're one of those (probably the majority) that leaves their computer on 24/7. Let's say your gaming computer's average power consumption, between idling and heavy usage, is maybe 200W. Let's say the power supply lasts an average 3 years. Let's say that the difference between a cheapo 75% efficient power supply and an excellent 95% efficient supply is $50. Then the better supply saves 40W on average, or 1051 kWh over its lifespan. At an average US electricity price of, what, 12 cents per kWh, that's a savings of $126. You not only help the environment, but you easily save yourself money.

It's not just power supplies that matter - the same logic can be applied to processors, graphics cards, and other hardware as well. Always check the power consumption - not just for the environment, but for your pocketbook as well. Often it saves money to spend more upfront.

Comment Re:Not far enough. (Score 1) 78

IMHO, countries that care about pollution should set up a Pollution-Added Tax (PAT), equivalent to VAT, replacing their current patchwork of pollution regulations. Since VAT is already clearly in compliance with WTO rules (given that it exists), PAT should be as well. Just like how VAT works by taxing products at each stage of adding value to them during manufacture, PAT would tax them by the embodied pollution in their manufacture during that stage (plus any "delayed" pollution released when the product is consumed). And like VAT, PAT goods for export would receive a full tax rebate, and goods for import from non-PAT states would be taxed on entry.

The main point is that states with weaker pollution regulations cannot gain an unfair economic advantage over states with stronger pollution regulations. Thus it encourages even non-member-states to tighten their regulations.

Comment Re:Sanctioning NSA/FBI for spying all? (Score 2) 78

Things like Stuxnet is not at all what the person was talking about. They're talking about hacks to try to embarrass people or steal corporate secrets. Stuxnet was to take down a nuclear program, which is clearly a geopolitical, not industrial, goal.

My personal opinion: countries breaking into each other's governments or trying in general to gather/use classic "spying" data for geopolitical purposes is fair game. State-sponsored industrial espionage is not. That said, even in the first case, one runs the risk of uncontrolled escalation, so it's important for all sides to keep themselves in check and mutually agree to ratchet down the activity from time to time, for everyone's sake.

Also: it probably hasn't gotten past the US that it's in an advantageous state right now. Russia hasn't been more vulnerable in a long time, and now even China's star has taken a pounding in the market. US industry is benefiting from cheap thermal energy prices due to low cost shale gas. And Europe is probably going to be on the US's side in all of this.

Comment Re:"Denali" = anagram for "Denial" (Score 1) 389

I don't have a very clean way - I usually do egrep "^......$" /usr/share/dict/words (with the number of dots matching the length of the word) and then pipe it into a series of other greps - for example for two "r"s I'd do egrep -i "r.*r" while for one d I'd just use grep -i "d". There's probably a better way.

Comment Re:For me, it will always remain the mountain... (Score 4, Interesting) 389

I can't remember who it was... it might have been Halldór Laxnes... who said that a piece of nature isn't really a piece of nature unless it doesn't have a name. That is, the first thing people do once they start interacting with an object or place is to give it a name, and so once something is named it starts to become about the history of people rather than the history of the land itself. And that if you want to establish a real connection with nature, you don't go sit on top of that well-known named peak that people climb... you go to that little nameless stream or that remote nameless cliff or whatnot - places which tell only their own story.

To downgrade the human mind is bad theology. - C. K. Chesterton

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