But the finding of bacteria who could survive a prolonged space journey (which I believe we have now found) means that the mechanism that the Drake equation ignores completely (the probability of life travelling from one planet to another via pieces knocked off the planet by large scale meterorite impacts) could easily come to dominate the dissemination of life from a very small number of independently evolved sources.
Since we know the probability of life spontaneously appearing in at least ONE place in the universe is 1.0 (because we're here), you can come up with a new set of equations to predict the rate at which life could spread on meteorite fragments.
Some of the numbers in the Drake equations are truly unknowns - putting a huge uncertainty factor on the results. Using dissemination of life from a single point should provide much more reliable lower bounds on the estimates for intelligent alien life that we might search for with SETI.
There is some clever science involved in this stuff.
Our house is built on a heavy clay soil known locally as 'black gumbo' - the surface of our land rises and falls up to 6" between the wettest and driest parts of the year. As a consequence, the house is built on a 'waffle slab' - which means that they dug broad trenches in a waffle pattern, threaded steel cables through tubes in the center of those trenches - then filled them up with reinforced concrete. Once the slab was poured and dried, they 'post-tensioned' it by pulling the cables very tight to apply positive pressure over the whole thing. The re-bar in the slab was left poking upwards around the edges so that when the walls were poured, they form a seamless concrete 'container'.
The whole house is therefore like a solid concrete box (except for the roof and door/window openings). It's designed to float on the underlying clay soil - with the waffles in the slab providing traction to stop it sliding sideways. Since concrete is very strong under compression but has almost no strength under tension, the post-tensioning trick prevents it from cracking under the hydrostatic forces from the clay soil.
The 'waffle slab' part is a very standard construction technique on this kind of soil.
The interior walls are just regular wood-framed walls with sheet-rock. Since they don't play any part in supporting anything - or insulating anything, they are little more than room dividers. Making them out of concrete would be unnecessary - and limit scope for remodelling the interior in the future.
The floor upstairs is bolted to the exterior concrete walls using bolts that were placed into the walls as the concrete was setting. This means that the interior walls play no part in supporting the floor at all.
There are a couple of other 'convenience' features of the foam 'bricks' that I didn't mention: The carbon fibre 'webs' that keep the foam in place while the concrete is poured have to be strong because they support the pressure of the liquid concrete until it sets. They also extend into the foam blocks. This turns out to be useful if you need to screw something to the exterior walls because you can screw into the carbon-fibre instead of trying to hold up a shelf with just foam and sheet-rock!
I designed the house myself (although I paid an architect to redraw my plans, certify that it was legal and such) - but the idea to use this construction technique happened after I thought I'd finalised the plans. In retrospect, that was a bad thing.
Just like Lego bricks, your house design is limited by the size and shapes of the 'bricks' they make. When I built (about 6 years ago) they only had 90 and 45 degree corner bricks - so my design for hexagonal 'turrets' in the corners of the house had to be changed to octagonal turrets - with smaller windows as a consequence.
There was also a problem with where I wanted an exterior door that resulted in a long chain of complicated dependancies breaking down. As a result, my kitchen is 6" smaller than I designed it to be - so the refrigerator doesn't fit where I wanted it to be - so the kitchen isn't as ergonomically 'correct' as I'd intended...urgh!
Another downside is that routing cables and pipes through the outside walls had to be done before the sheet rock was put up so that they could cut channels into the foam for the conduits. Hence, it's essentially impossible to add more cabling along the external walls of the house - which is why all my 1GHz ethernet outlets are on the interior walls of the house!
Our house will certainly last well over 25 years - I used that number as a worst case.
The technology in our house is known as 'insulated concrete forms'. They built the house out of foam blocks just exactly as if they were Lego bricks (they even have the studs on top and interlocking holes underneath). Each brick is two thick foam blocks with a 6" gap between them. The two blocks are held at that spacing by a pair of carbon-fibre plates. As they build, they thread a web of re-bar inside. Once one floor is finished, they pour concrete down between the foam block, then build the interior walls, and the upstairs floor - then proceed with another layer of "lego" bricks - and then fill that with concrete. Then they brick up the outside and sheet-rock the inside. The result is brick/1"foam/6"concrete/1"foam/quarter-inch plaster. The walls are now almost a foot thick.
The house is supposed to be able to resist 300mph winds (which is actually a significant bonus in Texas).
Whilst concrete isn't the most ecologically sound material, the long life the house should have (FAR in excess of most Texas wood + stucco or siding buildings) ought to be worth it on balance.
It has a couple of other unexpected benefits - one is that there are almost never any insects in the house because the floor slab and the walls form one continuous concrete barrier. Another is that it's very quiet inside. The insulation that keeps out the summer heat also keeps out the noise.
The major downside is that it's not possible to add new windows or doors once construction is underway. It's also necessary that the garage is heated/air-conditioned because there is no insulated wall between it and the main body of the house. We needed a special insulated garage door in order to avoid that being a major energy lossage.
The problem with a device like this at it's high price is that it changes just too many variables.
* You might pursuade people that the wonderous new input device was worth looking at on a fairly standard PDA.
* You might sell them a fairly standard PDA with some new no-name Operating System.
* You might even convince them that they need 7 CPU's on a regular PDA.
* You might maybe sell people a pretty standard PalmOS PDA from a company you've never heard of (if it's cheap enough).
But all those things at once (and at such a high price) are just spelling "DISASTER" to me.
It only takes one of those wonderously innovative things to be somewhat broken to make the darned thing useless - and what happens if the company goes bust tomorrow? They've already admitted that they've paid a fortune up-front to tool up to build a half million of these things. They must owe money out the wazoo - it's a high risk venture they are engaged with here.
Will they be there to fix up the bugs in an untried OS running on 7 CPU's in parallel? Will there be new applications for it? Will there be endless teething troubles with all of these new hardware widgets?
(And if it's a "TDA", why to they have 'pda' in their URL?)
In order to extract energy from the water, it's gotta slow it down somewhat. When you do that, you cause sediment to settle out prematurely where it never settled out before. That can change the direction of flow, causing erosion in new places and deposition in others - maybe cause loss of habitat for some animals and plants.
There isn't *ANY* power generation system that doesn't have some kind of impact. The issue is whether this has a more acceptable impact than the other ways to get that much power.
The problem I have with these projects is that if you spent the same amount of money on energy saving plans, you'd end up with the same results - but with LESS environmental impact - not more.
For example, I live in Texas where a large fraction of everyone's electricity bill is paying for airconditioning and heating. By spending about an extra 5% on the price of my house, I ended up with about three times better thermal insulation factor compared to a typical Texas home. As a result (since A/C and Heat are such large fraction of electric bills here), it's no suprise that my electric bills are about half what my friends and neighbours are getting for similar sized houses. (My house is built with this stuff: http://oikos.com/companies/grnblock.html)
Crunching the numbers, my additional 5% up-front cost is repayed in about 5 years...and the house should last at least 25 years so this is a really good deal.
However, getting people to pay that 5% up-front cost is HARD. (Why else would so few houses be built that way?)
But what if the government or the electricity generation companies paid you to add that extra insulation and took the cost of it back from your fuel bill savings in the form of a tax of some kind? An initial outlay of $20M would halve the electicity consumption of about 5,000 houses like mine. That's about the same as building a 3.5MW powerstation. Not as good as the 10MW one that they are planning to build in NY for $20M - but mine lasts for 25 years without maintenance, labor, etc - has not technical risk and has a really GOOD effect on the environment by reducing the net amount of electricity that has to be generated.
That's just one example - I'm sure there are others.
Did I read that right? In order to for me to bring a complaint against the broadcaster, *I* have to provide a tape of the show? Doesn't that conflict rather seriously with the broadcast flag that will in future prevent me from making that recording?
Three times redder than they human eye can see?!?!
on
Titan's Surface Revealed
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· Score: 3, Insightful
"Near-infrared colors, some three times redder than the human eye can see"
What the fsck does that mean?
Some of the wavelengths are three times as long as 'Red'?
Visible 'red' light is around.65 to maybe.75 micrometers. So are they are saying 2.1um or so?
I do wish these articles would just say what they mean and not try to make it seem more 'amazing' with fuzzy statements like that. It's like "WOW! THREE TIMES REDDER!" - when in fact, near IR is nothing special - most cheap camcorders can take pretty good pictures in that frequency range.
Back in the early 1980's, we took delivery of our first UNIX machine - a 68000 based box with a bunch of dumb terminals.
I had used UNIX quite a bit in college - so I knew the basics but I'd never been a sysadmin.
When the machine was delivered and installed, the field tech guy who dropped it off was in a bit of a hurry so he set the system up - left me to play with it and said he be back the next day to show us how to start it up and shut it down cleanly...but told us NOT to reboot it that night because we didn't know the shutdown procedures.
So later that night, I was dinking with the system - I had all of the dumb terminals logged in and did a 'ps -ef'. There seemed to be a lot of processes running that I didn't recognise. Well, I was a complete newbie - but brimming with overconfidence because I was the only one in the company who 'knew UNIX'.
I knew that keeping a sharp eye out for 'rogue processes' was the sysadmin's job. So I killed off the ones I didn't recognise. Then, deciding that I'd had enough, I logged off, intending to head home. I was suprised to find that I didn't get a new login prompt. So I went over to one of the other terminals and tried logging out of that...same thing - no 'login:' prompt. (At this point, you'll realise that I'd killed off the 'init' task).
I was getting frantic - I didn't know how to deal with this and I was down to only one remaining logged in terminal which I didn't dare to log out of. I didn't want to look a complete idiot in front of the field tech guy and my co-workers the following day - and I didn't know how to properly reboot the system.
In the end, I flipped off the circuit breaker to that room and went home.
Fortunately (and perhaps unsuprisingly), nothing actually went wrong - but I was scared and shaking when the system was coming back up and went into a protracted disk startup check.
We have the Sony AV2100 - it was once considered up-market for a 'learning remote' but not in the thousands of dollars range. I paid a little over $100 - but nowadays you can pick one up on eBay for around $30.
Ours has replaced every single remote we have in our family room (EIGHT of them!!). It even successfully learned Lego Mindstorms commands.
It's better than just a regular record/replay learning remote because it can chain together bunches of commands from different remotes and knows things like "when you are controlling the TV, you should still send volume control messages to the home-theatre amplifier". With the chained commands, I can press a single touch-screen button to tell my TV to listen to the DVD player, the DVD player to eject so I can put a disk in, the Amplifier to go to 'Action Movie' mode, the TV to accept wide-format video and the dimmer on the room lighting to go to 10% brightness. Now if I can just get the Lego robot to fetch me a beer, I'll be in business!
The AV2100 has regular mechanical buttons for common things like channel changing, volume control and switching major modes - but it also has a large LCD panel with a touch screen for everything else. The blue back-light on the LCD is worth having so you can see what you are doing in a darkened room.
The best thing of all - it's too big to lose between two sofa cushions. Trust me - that's far-and-away it's best feature!
Given that there are a finite number of viewers - and the market is pretty much saturated, who would be the extra eyeballs to expand the market?
Whether TV is paid for by advertising or by subscription: that finite number of people fixes the total amount of cash that's available for making programs.
If there are more channels - then there must either be vastly more reruns - or vastly lower production costs for new shows. Neither of those are very acceptable to either viewership or advertisers - both of whom want new, high quality shows.
I don't understand how anyone ever thought this would be a sustainable model.
The problem with the US constitutional right to free speech is that it doesn't say anything about a necessary symmetry - the right not to have to listen.
In the case of Spam, Spyware and other such intrusions, I have no problem with these people posting their spam and their spyware on websites, clearly labelled as what they are. In fact, I'd strongly uphold their rights to do so.
However, when I say that I don't want to listen to that stuff, I REALLY need a constitutionally protected right to not listen.
When someone stands on a soapbox and starts some political diatribe on a street corner, the constitution gives him the right to do so. Where is my right to cover my ears and walk the other way?
I don't think the intention was ever to give people the right to force others to listen to their speech...it's there to stop third parties from preventing a speaker from conveying information to a willing recipient.
They can't implement anything like a challenge/response method (unless they don't want to sell cars in California) because the method for reading codes is mandated by Californian state law. What they *don't* mandate is the values for all possible error codes - presumably because there is no way to know up-front what kinds of errors cars might have in the future (Error J1234 - Your "Mr Fusion" unit needs more beer cans).
However, the error codes they could think of back in the mid-1990's that might be useful during a state-mandated emissions control test *ARE* fully documented. Hence, you can tell whether your Oxygen sensor has crapped out - but not necessarily whether the flat tyre monitor is reporting a problem.
HOWEVER, they most certainly DO implement that kind of system for doing things like re-flashing the ECU software. The protection on THAT is like Fort Knox! On my MINI Cooper, if you try to reflash the ECU and get the response to the challenge wrong, the entire car completely shuts down (to the point where you can't even open the doors) for THREE HOURS!
I don't think anyone mentioned this yet - so I will.
I'm running a project to write a GPL'ed car diagnostic tool that runs under Linux (and probably BSD too). It's called 'freediag' and the current version works well enough to read out error codes (and possibly zero them) on at least a few types of car.
You'll need to buy or build a cable to connect a laptop to the OBD-II port on your car. A simple serial cable won't do because you have to have optoisolators to protect your valuable laptop from the rigours of the crappy signal quality you get from most cars. If you buy one, it'll set you back maybe $70.
Anyway - the project needs developers - and it needs testers (there are lot of different interface cables and a lot of different subtle variations on the supposed standard car interface).
If you are interested - head over to http://freediag.sf.net (of course!) and sign up to the developer's mailing list.
It's not a matter of 'encryption'. The codes are just four digit numbers - you can easily find out what codes your car has stored - what you don't know is what that number *MEANS*.
The state of California has mandated a certain set of error codes be standardized as a part of the 'OBD-II' standard. Those are mostly emissions-related - but they ARE standardized and well documented all over the place for cars less than maybe 5 or 6 years old. Older cars don't have to conform to any special standard - so they are all over the place.
Some car companies play nice and release all of their error codes publically - others treat them as closely-guarded secrets. Sometimes those secrets 'leak out' and you can find out what they mean with an appropriate web search. Sometimes they don't.:-(
I don't see how the DMCA could be involved here - you read out codes - they are just numbers.
There is certainly a trick to do that on the MINI Cooper. Something like holding down the trip-meter reset button for 20 seconds whilst turning on the ignition. That dumps you into some kind of menu that pops up on the odometer display. You can step through that menu with the trip meter - one step of which displays the error code(s).
This isn't documented anywhere in the owner's manual - but heck - that's what mailing lists are for!
Tightening the gas cap (at least on my car - A MINI Cooper'S) doesn't make the error code go away immediately. The Engine management system has to ascertain that the fuel tank pressurization stuff is all working correctly before it'll turn the 'Check Engine' light off - and that takes several days of normal driving.
Think about solving two clues that intersect on a 2D crossword. You have to find two words that fit the clues that share a common letter at the point where they intersect - right?
One of the things that makes crosswords harder is when there are multiple possible solutions for each clue - and the only way to find which is the right one is by co-solving the two clues. However, it might be that even then there are multiple pairs of words that fit the clues and satisfy the common-letter constraint. In that case, you have to look at another word or words that shares a common letter with one of the two clues. This could lead you off into solving MANY more clues just in order to get those first two words right.
Well, in a 3D crossword (presuming there are locations where THREE clues intersect), there would be fewer sets of THREE words solutions that satisfy the constraints at each intersection than there are TWO word solutions in a 2D crossword.
However, this is definitely a bit of a stretch. I don't think a nicely presented 3D crossword would be much different from a 2D one - the hardest part of hard crosswords is finding answers that fit the clues - and that doesn't change when you go to 3D.
Many years ago, when I was into radio controlled planes, there was a guy who built lots of improbable flying machines. Most of them were constructed from foam polystyrene with relatively large motors. With enough thrust, and very little weight, you don't need much in the way of aerodynamics to make something fly.
I recall he built and successfully flew several flying saucers, a brick, a flying carpet (complete with a guy with a turban riding cross-legged on it)...and his crowning achievement: Santa's sleigh - complete with reindeer. Compared to that, getting a model of the Enterprise to fly is a piece of cake - it has plenty of surfaces that could generate lift - and you can see from the video that it needs a pretty steep angle of attack to keep it up.
The phenomenon of CD-Rot has been known for at least 15 years.
I believe it comes about when there are microscopic pin-holes in the aluminium layer within the CD. Over time, an effect akin to surface-tension in liquids causes these holes to grow - until they get sufficiently large (and numerous) to cause enough data dropout to overwhelm the error correction mechanisms of the player.
CD's that never had pin-holes don't develop them later - which explains how come some disks are magically immune to the problem where others die in only a few years.
I once heard that you can actually see these pin-holes once they've grown to a size that's not yet large enough to cause permenant errors. Hold the disk up to a bright light and see if you can see them. This may give you time to back up one that's "on the way out" before you lose it completely.
I believe the manufacturers developed an alternative material for the reflective layer about 10 years ago - but most pressing plants have not switched over to it. I wonder whether their reluctance to do so is rooted in a desire to have people re-buy the same CD's over and over.
It's roughly a cylinder 2.9 miles long x 1.5 miles in cross-sectional diameter. That's a volume of about 21 cubic kilometers...21 giga-cubic-meters. A cubic meter of basalt rock weighs in at 2800kg under earth gravity...so we are up to something like 5.5 tera-newtons of mass.
We know that:
Force = mass x accelleration
dist = accelleration x time x time / 2
What saves you when you are trying to move something like this is that 'time-squared' term. Doubling the time over which you push on the rock quadruples the distance you finally move it by. This means that a tiny accelleration applied over a long time is the way to go (not a multi-megaton nuclear blast applied over a millisecond).
The rock has a huge mass - but the force you need is the mass times the accelleration - so that tiny accelleration times that huge mass gets you into the realm of reasonably small forces...but you have to plan on applying them for many YEARS.
To deflect this rock by a couple of earth radii, (say 10,000 km) over 100 years, needs a tiny (but continuous) accelleration of.0000000000001 meters per second per second - and even for a rock that big, that's only about half a newton/meter of force - that's *nothing*, a car engine can do a couple of hundred Newton/meters.
So - the most gentle of pushes - if applied over a 100 years is plenty.
This also eliminates any risk of smashing it to bits - and gives you plenty of time to correct any mistakes, refuel your motor, etc.
Of course if you leave it until the final year before impact before you act, you need 10,000 times as much power (still do-able with enough 'bolt-on' rockets I think - but maybe you could break it up with that much force).
If you let the politicians argue about who'se going to pay for it until a month before impact, you need a million times as much power and it's obviously too late.
That's why we need LOTS of notice if one of these brutes coming close. 600 years is enough - but I'd definitely get very nervous if it was only 100 years away.
Saving individual humans is a lot different from saving humanity.
All we'd need to do would be to send a genetically reasonable sample - then apply vigerous birth control to the population of earth a couple of generations before the big crunch so nobody actually dies when it happens. Life would not be good for the few most elderly survivors - so once the population has naturally dwindled to something reasonable, you pack them off in the last few spaceships.
Slashdot Mirror
But the finding of bacteria who could survive a prolonged space journey (which I believe we have now found) means that the mechanism that the Drake equation ignores completely (the probability of life travelling from one planet to another via pieces knocked off the planet by large scale meterorite impacts) could easily come to dominate the dissemination of life from a very small number of independently evolved sources.
Since we know the probability of life spontaneously appearing in at least ONE place in the universe is 1.0 (because we're here), you can come up with a new set of equations to predict the rate at which life could spread on meteorite fragments.
Some of the numbers in the Drake equations are truly unknowns - putting a huge uncertainty factor on the results. Using dissemination of life from a single point should provide much more reliable lower bounds on the estimates for intelligent alien life that we might search for with SETI.
There is some clever science involved in this stuff.
Our house is built on a heavy clay soil known locally as 'black gumbo' - the surface of our land rises and falls up to 6" between the wettest and driest parts of the year. As a consequence, the house is built on a 'waffle slab' - which means that they dug broad trenches in a waffle pattern, threaded steel cables through tubes in the center of those trenches - then filled them up with reinforced concrete. Once the slab was poured and dried, they 'post-tensioned' it by pulling the cables very tight to apply positive pressure over the whole thing. The re-bar in the slab was left poking upwards around the edges so that when the walls were poured, they form a seamless concrete 'container'.
The whole house is therefore like a solid concrete box (except for the roof and door/window openings). It's designed to float on the underlying clay soil - with the waffles in the slab providing traction to stop it sliding sideways. Since concrete is very strong under compression but has almost no strength under tension, the post-tensioning trick prevents it from cracking under the hydrostatic forces from the clay soil.
The 'waffle slab' part is a very standard construction technique on this kind of soil.
The interior walls are just regular wood-framed walls with sheet-rock. Since they don't play any part in supporting anything - or insulating anything, they are little more than room dividers. Making them out of concrete would be unnecessary - and limit scope for remodelling the interior in the future.
The floor upstairs is bolted to the exterior concrete walls using bolts that were placed into the walls as the concrete was setting. This means that the interior walls play no part in supporting the floor at all.
There are a couple of other 'convenience' features of the foam 'bricks' that I didn't mention: The carbon fibre 'webs' that keep the foam in place while the concrete is poured have to be strong because they support the pressure of the liquid concrete until it sets. They also extend into the foam blocks. This turns out to be useful if you need to screw something to the exterior walls because you can screw into the carbon-fibre instead of trying to hold up a shelf with just foam and sheet-rock!
I designed the house myself (although I paid an architect to redraw my plans, certify that it was legal and such) - but the idea to use this construction technique happened after I thought I'd finalised the plans. In retrospect, that was a bad thing.
Just like Lego bricks, your house design is limited by the size and shapes of the 'bricks' they make. When I built (about 6 years ago) they only had 90 and 45 degree corner bricks - so my design for hexagonal 'turrets' in the corners of the house had to be changed to octagonal turrets - with smaller windows as a consequence.
There was also a problem with where I wanted an exterior door that resulted in a long chain of complicated dependancies breaking down. As a result, my kitchen is 6" smaller than I designed it to be - so the refrigerator doesn't fit where I wanted it to be - so the kitchen isn't as ergonomically 'correct' as I'd intended...urgh!
Another downside is that routing cables and pipes through the outside walls had to be done before the sheet rock was put up so that they could cut channels into the foam for the conduits. Hence, it's essentially impossible to add more cabling along the external walls of the house - which is why all my 1GHz ethernet outlets are on the interior walls of the house!
Our house will certainly last well over 25 years - I used that number as a worst case.
The technology in our house is known as 'insulated concrete forms'. They built the house out of foam blocks just exactly as if they were Lego bricks (they even have the studs on top and interlocking holes underneath). Each brick is two thick foam blocks with a 6" gap between them. The two blocks are held at that spacing by a pair of carbon-fibre plates. As they build, they thread a web of re-bar inside. Once one floor is finished, they pour concrete down between the foam block, then build the interior walls, and the upstairs floor - then proceed with another layer of "lego" bricks - and then fill that with concrete. Then they brick up the outside and sheet-rock the inside. The result is brick/1"foam/6"concrete/1"foam/quarter-inch plaster. The walls are now almost a foot thick.
The house is supposed to be able to resist 300mph winds (which is actually a significant bonus in Texas).
Whilst concrete isn't the most ecologically sound material, the long life the house should have (FAR in excess of most Texas wood + stucco or siding buildings) ought to be worth it on balance.
It has a couple of other unexpected benefits - one is that there are almost never any insects in the house because the floor slab and the walls form one continuous concrete barrier. Another is that it's very quiet inside. The insulation that keeps out the summer heat also keeps out the noise.
The major downside is that it's not possible to add new windows or doors once construction is underway. It's also necessary that the garage is heated/air-conditioned because there is no insulated wall between it and the main body of the house. We needed a special insulated garage door in order to avoid that being a major energy lossage.
The problem with a device like this at it's high price is that it changes just too many variables.
* You might pursuade people that the wonderous new input device was worth looking at on a fairly standard PDA.
* You might sell them a fairly standard PDA with some new no-name Operating System.
* You might even convince them that they need 7 CPU's on a regular PDA.
* You might maybe sell people a pretty standard PalmOS PDA from a company you've never heard of (if it's cheap enough).
But all those things at once (and at such a high price) are just spelling "DISASTER" to me.
It only takes one of those wonderously innovative things to be somewhat broken to make the darned thing useless - and what happens if the company goes bust tomorrow? They've already admitted that they've paid a fortune up-front to tool up to build a half million of these things. They must owe money out the wazoo - it's a high risk venture they are engaged with here.
Will they be there to fix up the bugs in an untried OS running on 7 CPU's in parallel? Will there be new applications for it? Will there be endless teething troubles with all of these new hardware widgets?
(And if it's a "TDA", why to they have 'pda' in their URL?)
In order to extract energy from the water, it's gotta slow it down somewhat. When you do that, you cause sediment to settle out prematurely where it never settled out before. That can change the direction of flow, causing erosion in new places and deposition in others - maybe cause loss of habitat for some animals and plants.
There isn't *ANY* power generation system that doesn't have some kind of impact. The issue is whether this has a more acceptable impact than the other ways to get that much power.
The problem I have with these projects is that if you spent the same amount of money on energy saving plans, you'd end up with the same results - but with LESS environmental impact - not more.
For example, I live in Texas where a large fraction of everyone's electricity bill is paying for airconditioning and heating. By spending about an extra 5% on the price of my house, I ended up with about three times better thermal insulation factor compared to a typical Texas home. As a result (since A/C and Heat are such large fraction of electric bills here), it's no suprise that my electric bills are about half what my friends and neighbours are getting for similar sized houses. (My house is built with this stuff: http://oikos.com/companies/grnblock.html)
Crunching the numbers, my additional 5% up-front cost is repayed in about 5 years...and the house should last at least 25 years so this is a really good deal.
However, getting people to pay that 5% up-front cost is HARD. (Why else would so few houses be built that way?)
But what if the government or the electricity generation companies paid you to add that extra insulation and took the cost of it back from your fuel bill savings in the form of a tax of some kind? An initial outlay of $20M would halve the electicity consumption of about 5,000 houses like mine. That's about the same as building a 3.5MW powerstation. Not as good as the 10MW one that they are planning to build in NY for $20M - but mine lasts for 25 years without maintenance, labor, etc - has not technical risk and has a really GOOD effect on the environment by reducing the net amount of electricity that has to be generated.
That's just one example - I'm sure there are others.
Did I read that right? In order to for me to bring a complaint against the broadcaster, *I* have to provide a tape of the show? Doesn't that conflict rather seriously with the broadcast flag that will in future prevent me from making that recording?
"Near-infrared colors, some three times redder than the human eye can see"
.65 to maybe .75 micrometers. So are they are saying 2.1um or so?
What the fsck does that mean?
Some of the wavelengths are three times as long as 'Red'?
Visible 'red' light is around
I do wish these articles would just say what they mean and not try to make it seem more 'amazing' with fuzzy statements like that. It's like "WOW! THREE TIMES REDDER!" - when in fact, near IR is nothing special - most cheap camcorders can take pretty good pictures in that frequency range.
Ack!
So on Titan they play tic-tac-toe with Oh's, X's *and* Zeroes! Boy those guys are just *so* alien - we may never learn to communicate with them.
Back in the early 1980's, we took delivery of our first UNIX machine - a 68000 based box with a bunch of dumb terminals.
I had used UNIX quite a bit in college - so I knew the basics but I'd never been a sysadmin.
When the machine was delivered and installed, the field tech guy who dropped it off was in a bit of a hurry so he set the system up - left me to play with it and said he be back the next day to show us how to start it up and shut it down cleanly...but told us NOT to reboot it that night because we didn't know the shutdown procedures.
So later that night, I was dinking with the system - I had all of the dumb terminals logged in and did a 'ps -ef'. There seemed to be a lot of processes running that I didn't recognise. Well, I was a complete newbie - but brimming with overconfidence because I was the only one in the company who 'knew UNIX'.
I knew that keeping a sharp eye out for 'rogue processes' was the sysadmin's job. So I killed off the ones I didn't recognise. Then, deciding that I'd had enough, I logged off, intending to head home. I was suprised to find that I didn't get a new login prompt. So I went over to one of the other terminals and tried logging out of that...same thing - no 'login:' prompt. (At this point, you'll realise that I'd killed off the 'init' task).
I was getting frantic - I didn't know how to deal with this and I was down to only one remaining logged in terminal which I didn't dare to log out of. I didn't want to look a complete idiot in front of the field tech guy and my co-workers the following day - and I didn't know how to properly reboot the system.
In the end, I flipped off the circuit breaker to that room and went home.
Fortunately (and perhaps unsuprisingly), nothing actually went wrong - but I was scared and shaking when the system was coming back up and went into a protracted disk startup check.
We have the Sony AV2100 - it was once considered up-market for a 'learning remote' but not in the thousands of dollars range. I paid a little over $100 - but nowadays you can pick one up on eBay for around $30.
Ours has replaced every single remote we have in our family room (EIGHT of them!!). It even successfully learned Lego Mindstorms commands.
It's better than just a regular record/replay learning remote because it can chain together bunches of commands from different remotes and knows things like "when you are controlling the TV, you should still send volume control messages to the home-theatre amplifier". With the chained commands, I can press a single touch-screen button to tell my TV to listen to the DVD player, the DVD player to eject so I can put a disk in, the Amplifier to go to 'Action Movie' mode, the TV to accept wide-format video and the dimmer on the room lighting to go to 10% brightness. Now if I can just get the Lego robot to fetch me a beer, I'll be in business!
The AV2100 has regular mechanical buttons for common things like channel changing, volume control and switching major modes - but it also has a large LCD panel with a touch screen for everything else. The blue back-light on the LCD is worth having so you can see what you are doing in a darkened room.
The best thing of all - it's too big to lose between two sofa cushions. Trust me - that's far-and-away it's best feature!
Given that there are a finite number of viewers - and the market is pretty much saturated, who would be the extra eyeballs to expand the market?
Whether TV is paid for by advertising or by subscription: that finite number of people fixes the total amount of cash that's available for making programs.
If there are more channels - then there must either be vastly more reruns - or vastly lower production costs for new shows. Neither of those are very acceptable to either viewership or advertisers - both of whom want new, high quality shows.
I don't understand how anyone ever thought this would be a sustainable model.
The problem with the US constitutional right to free speech is that it doesn't say anything about a necessary symmetry - the right not to have to listen.
In the case of Spam, Spyware and other such intrusions, I have no problem with these people posting their spam and their spyware on websites, clearly labelled as what they are. In fact, I'd strongly uphold their rights to do so.
However, when I say that I don't want to listen to that stuff, I REALLY need a constitutionally protected right to not listen.
When someone stands on a soapbox and starts some political diatribe on a street corner, the constitution gives him the right to do so. Where is my right to cover my ears and walk the other way?
I don't think the intention was ever to give people the right to force others to listen to their speech...it's there to stop third parties from preventing a speaker from conveying information to a willing recipient.
So there is a million dollar prize for proving Reimann - how much do you get if you manage to disprove it?
Yes - it does.
They can't implement anything like a challenge/response method (unless they don't want to sell cars in California) because the method for reading codes is mandated by Californian state law. What they *don't* mandate is the values for all possible error codes - presumably because there is no way to know up-front what kinds of errors cars might have in the future (Error J1234 - Your "Mr Fusion" unit needs more beer cans).
However, the error codes they could think of back in the mid-1990's that might be useful during a state-mandated emissions control test *ARE* fully documented. Hence, you can tell whether your Oxygen sensor has crapped out - but not necessarily whether the flat tyre monitor is reporting a problem.
HOWEVER, they most certainly DO implement that kind of system for doing things like re-flashing the ECU software. The protection on THAT is like Fort Knox! On my MINI Cooper, if you try to reflash the ECU and get the response to the challenge wrong, the entire car completely shuts down (to the point where you can't even open the doors) for THREE HOURS!
I don't think anyone mentioned this yet - so I will.
I'm running a project to write a GPL'ed car diagnostic tool that runs under Linux (and probably BSD too). It's called 'freediag' and the current version works well enough to read out error codes (and possibly zero them) on at least a few types of car.
You'll need to buy or build a cable to connect a laptop to the OBD-II port on your car. A simple serial cable won't do because you have to have optoisolators to protect your valuable laptop from the rigours of the crappy signal quality you get from most cars. If you buy one, it'll set you back maybe $70.
Anyway - the project needs developers - and it needs testers (there are lot of different interface cables and a lot of different subtle variations on the supposed standard car interface).
If you are interested - head over to http://freediag.sf.net (of course!) and sign up to the developer's mailing list.
It's not a matter of 'encryption'. The codes are just four digit numbers - you can easily find out what codes your car has stored - what you don't know is what that number *MEANS*.
:-(
The state of California has mandated a certain set of error codes be standardized as a part of the 'OBD-II' standard. Those are mostly emissions-related - but they ARE standardized and well documented all over the place for cars less than maybe 5 or 6 years old. Older cars don't have to conform to any special standard - so they are all over the place.
Some car companies play nice and release all of their error codes publically - others treat them as closely-guarded secrets. Sometimes those secrets 'leak out' and you can find out what they mean with an appropriate web search. Sometimes they don't.
I don't see how the DMCA could be involved here - you read out codes - they are just numbers.
There is certainly a trick to do that on the MINI Cooper. Something like holding down the trip-meter reset button for 20 seconds whilst turning on the ignition. That dumps you into some kind of menu that pops up on the odometer display. You can step through that menu with the trip meter - one step of which displays the error code(s).
This isn't documented anywhere in the owner's manual - but heck - that's what mailing lists are for!
Tightening the gas cap (at least on my car - A MINI Cooper'S) doesn't make the error code go away immediately. The Engine management system has to ascertain that the fuel tank pressurization stuff is all working correctly before it'll turn the 'Check Engine' light off - and that takes several days of normal driving.
It could be easier...maybe.
Think about solving two clues that intersect on a 2D crossword. You have to find two words that fit the clues that share a common letter at the point where they intersect - right?
One of the things that makes crosswords harder is when there are multiple possible solutions for each clue - and the only way to find which is the right one is by co-solving the two clues. However, it might be that even then there are multiple pairs of words that fit the clues and satisfy the common-letter constraint. In that case, you have to look at another word or words that shares a common letter with one of the two clues. This could lead you off into solving MANY more clues just in order to get those first two words right.
Well, in a 3D crossword (presuming there are locations where THREE clues intersect), there would be fewer sets of THREE words solutions that satisfy the constraints at each intersection than there are TWO word solutions in a 2D crossword.
However, this is definitely a bit of a stretch. I don't think a nicely presented 3D crossword would be much different from a 2D one - the hardest part of hard crosswords is finding answers that fit the clues - and that doesn't change when you go to 3D.
My son figured this out - with the help of some Lego - the answer is 332 (except for the Cherry ones that take a few less):
t ml
http://www.sjbaker.org/gallery/lickomatic/index.h
Many years ago, when I was into radio controlled planes, there was a guy who built lots of improbable flying machines. Most of them were constructed from foam polystyrene with relatively large motors. With enough thrust, and very little weight, you don't need much in the way of aerodynamics to make something fly.
I recall he built and successfully flew several flying saucers, a brick, a flying carpet (complete with a guy with a turban riding cross-legged on it)...and his crowning achievement: Santa's sleigh - complete with reindeer. Compared to that, getting a model of the Enterprise to fly is a piece of cake - it has plenty of surfaces that could generate lift - and you can see from the video that it needs a pretty steep angle of attack to keep it up.
The phenomenon of CD-Rot has been known for at least 15 years.
I believe it comes about when there are microscopic pin-holes in the aluminium layer within the CD. Over time, an effect akin to surface-tension in liquids causes these holes to grow - until they get sufficiently large (and numerous) to cause enough data dropout to overwhelm the error correction mechanisms of the player.
CD's that never had pin-holes don't develop them later - which explains how come some disks are magically immune to the problem where others die in only a few years.
I once heard that you can actually see these pin-holes once they've grown to a size that's not yet large enough to cause permenant errors. Hold the disk up to a bright light and see if you can see them. This may give you time to back up one that's "on the way out" before you lose it completely.
I believe the manufacturers developed an alternative material for the reflective layer about 10 years ago - but most pressing plants have not switched over to it. I wonder whether their reluctance to do so is rooted in a desire to have people re-buy the same CD's over and over.
Well, let's see. (Apologies for rough math!)
.0000000000001 meters per second per second - and even for a rock that big, that's only about half a newton/meter of force - that's *nothing*, a car engine can do a couple of hundred Newton/meters.
It's roughly a cylinder 2.9 miles long x 1.5 miles in cross-sectional diameter. That's a volume of about 21 cubic kilometers...21 giga-cubic-meters. A cubic meter of basalt rock weighs in at 2800kg under earth gravity...so we are up to something like 5.5 tera-newtons of mass.
We know that:
Force = mass x accelleration
dist = accelleration x time x time / 2
What saves you when you are trying to move something like this is that 'time-squared' term. Doubling the time over which you push on the rock quadruples the distance you finally move it by. This means that a tiny accelleration applied over a long time is the way to go (not a multi-megaton nuclear blast applied over a millisecond).
The rock has a huge mass - but the force you need is the mass times the accelleration - so that tiny accelleration times that huge mass gets you into the realm of reasonably small forces...but you have to plan on applying them for many YEARS.
To deflect this rock by a couple of earth radii, (say 10,000 km) over 100 years, needs a tiny (but continuous) accelleration of
So - the most gentle of pushes - if applied over a 100 years is plenty.
This also eliminates any risk of smashing it to bits - and gives you plenty of time to correct any mistakes, refuel your motor, etc.
Of course if you leave it until the final year before impact before you act, you need 10,000 times as much power (still do-able with enough 'bolt-on' rockets I think - but maybe you could break it up with that much force).
If you let the politicians argue about who'se going to pay for it until a month before impact, you need a million times as much power and it's obviously too late.
That's why we need LOTS of notice if one of these brutes coming close. 600 years is enough - but I'd definitely get very nervous if it was only 100 years away.
Saving individual humans is a lot different from saving humanity.
All we'd need to do would be to send a genetically reasonable sample - then apply vigerous birth control to the population of earth a couple of generations before the big crunch so nobody actually dies when it happens. Life would not be good for the few most elderly survivors - so once the population has naturally dwindled to something reasonable, you pack them off in the last few spaceships.