2430 posts • joined 10 Jun 2009
Where is it all going?
In the first instance, into plants. Measuring CO2 in the atmosphere shows minima every Northern hemisphere summer, and maxima every winter, as the leaves in the Northern hemisphere's deciduous and annual plants grow and decay. (The land area of the Southern hemisphere is considerably smaller so it doesn't fully compensate).
Some of that plant matter doesn't decay annually. It may be trapped for longer, as dead roots, humus in soil, peat bogs, and organics in sediment.
What's going on with plankton in the oceans is probably the most important thing long-term. Much of the carbon in dead plankton sinks down to the ocean deeps, from where it may not be released for geological ages. Is more CO2 being matched by an increase in plankton and therefore accumulation of organic matter on the deep ocean floor? We don't know. I'd neither count on it, nor rule it out.
Incidentally, our agricultural practices that create unnatural dust in the atmosphere are almost certainly resulting in an increased supply of iron to the ocean surface. And the biggest limitation on oceanic plankton growth is a shortage of iron. Accidental geo-engineering in progress?
Root to shoot ratio
How much of this is explained by plants optimizing themselves?
As "food", plants need CO2 from the atmosphere, and everything else from in the ground. They'll grow so as to balance the availability of those two sources. More CO2 in the atmosphere means that the plant can grow faster and bigger, but only if it shifts its growth to favour its root system, thereby obtaining a proportionately increased supply of water and minerals.
When the plant dies, the deeper its roots, the longer the carbon in them stays out of the atmosphere.
Re: This one is way too easy
Could you make a gun barrel out of plastic, even for just one shot at short range? I'd have thought it had to be steel to resist the firing pressure (and of course extreme precision machining needed as well for long-range accuracy). Definitely the hardest component to DIY and the one most in need of regulatory control.
If I wanted to kill someone at short range I'd make a crossbow. Just as deadly, less noisy, no technology needed that they didn't have in the middle ages (though modern alloys and composites would let you make it smaller and more powerful).
Re: This is going to get interesting soon...
Polythene and paraffin wax are pretty similar. (Same chemical formula CH3.(CH2)N.CH3, much bigger N for polythene). I expect with a bit of tinkering, they're interchangeable. At the printer end, the problem would be feeding wax "wire" which wouldn't have the tensile strength of polythene. At the lost wax end, you'd need to investigate whether it burns out of a clay mould as cleanly as wax. Molten wax will rapidly soak into porous clay. With polythene, you'd probably have to "cook" it for longer, and watch out for problems caused by gas pressure build-up behind a still-solid or highly viscous polythene plug.
Re: Metalwork class
Lathes and milling machines are computer-controlled these days. Have been for quite a while (since before 3D printers arrived).
I expect that a keen hobbyist could pick up an old manual milling machine and convert it to computer operation in his garage. You'd just have to replace the wheels that are turned by hand with appropriate stepper motors and sensors and controllers. The rest is programming.
BTW learning to use a manual lathe or milling machine is not at all hard. (Learning to use it well, that's quite another matter).
Re: Bloody wonderful, dont idiots ever think first?
It's just as likely that microdots or similar will be added to the plastic, so that an item can be traced through the purchasing system to the person who bought it.
Fail. Make your own feedstock out of commodity plastic items purchased at Wal-Mart, if you've got something to hide. Can it be that hard to work out how to re-melt and extrude polythene, ABS, etc.?
Restrict the technology and it will be driven underground, which means that you won;t be able to use it for tinkering with harmless things, but there will still be someone turning out knock-off copies of gun components for a black-market profit. Same as for recreational drugs, commercial sex, illegal porn, ....
At present the best hope is to restrict the gun barrels, which are clearly the hardest components to make. And despite the above, I'm still glad I live in a country where posession of a complete gun is strictly controlled. I feel I have less to fear from gun-bearing career criminals than from gun-bearing lunatics or gun-bearing mobs.
Re: Bloody wonderful, dont idiots ever think first?
Surely would make a lot more sense to regulate guns. Or if you insist on the right to bear arms, to insist on the gun barrels being "serialized" and controlled rather than the bit which works even if printed out of plastic.
Out of interest, how much does a computer-controlled milling machine cost these days? How hard would it be for a hobbyist to make his own computer-controlled milling machine out of a surplus manually-controlled milling machine plus some stepper motors and controllers?
I wonder whether J. Random Lunatic really cares much about "precise". How precise do you need on full auto at a range of ten yards?
Immortality - cause for optimism?
Just realized, no-one seems to have mentioned the one SF dream that might make things a lot better in a hurry and which might come about in some of our lifetimes. Immortality (second-grade). It may be possible to slow down or turn off the senescence mechanism that's biologically programmed into our stem cells. If perfect, we'd then enjoy the same life-expectancy and health at 70, or 100, or 200, that we enjoyed at 30. If less perfect, we might still get a few more decades of middle-aged health. We'd still die, eventually, of accident or incurable illness or other sorts of ageing that medicine couldn't deal with. But we might start treating the future of our planet with the respect it deserves, if we knew we might be living a few hundred years longer, rather than just a few decades.
Re: Sci-fi 'tech'
Actually there is at least one technological revolution in full flood right now: biotech (and GM). It's (surprisingly? ) far under most people's radar, because the main applications so far are
- pharmaceuticals, which we don't think about until we're ill, and then either the medics can cure us, or they can't and we accept our fate. No change since the middle ages, really, except the pills work somewhat more often these days.
- food, which we eat the same way whether it's GM or not, and most of us don't really know or care.
- raw materials (made by bacteria, GM or just selectively bred) which then go into the same old manufacturing chains. Once upon a time, citric acid was extracted from citrus fruit.
But one day soon, that might change dramatically. For example, on the optimistic side, what if instead of having a house built, you could just plant some seeds, and occasionally spray the developing house-treees with hormones to control the shapes of the walls and windows? Or grow GM seaweed that concentrates your element of need (Gold? Uranium? Europium?) out of the seawater, courtesy of a precisely engineered molecular sieve? Or solve global warming with a crop plant engineered to grow its roots far deeper than nature says it needs to, thereby burying lots of carbon for a long time?
And on the pessimistic side, it could all go horribly wrong (the cliche being zombie-horror fiction).
Some SF authors do get it, but a lot of those I've read illustrate that people who know their bioscience often don't know their physics.
Mirror of our times?
The state of SF is because it's reflecting the times we live in, or extrapolating them into the future. And there's not much to be optimistic about in today's society.
IT, for example, seems to have gone from being an enabling tool, to being a tool for repression. Omnipresent surveillance. No respect for privacy. Patent wars (that the small guys can't afford to fight). A complete disrespect for sound engineering principles, especially if they get in the way of making money in the short term. And worst, we've layered all the new infrastructure (which is frighteningly fragile) on top of old infrastructure (which was once robust, but which we're allowing to crumble, because our leaders don't understand that it supports the new stuff).
More widely there are issues of resource depletion, population increase and ecological overload, that are almost universally regarded as "too hard" and ignored. By the time they bite so hard they cannot be ignored, it'll be far too late to fix them.
Personally, I'd call today's reality a dystopia, and I can't see it getting any better. Pessimism is assuming it's going to get much worse very fast in the near future. A global crash (and not just the financial one, that we're already in). Thinking things are going to get a lot better very quickly isn't optimism, it's denial. Optimism is thinking that we'll muddle though, somehow.
Yes, I read it. The physics was nonsense. As a parable, I've read much better SF. I found the fall of Namqem particularly worrisome (along with most of the other back-story in Vinge's "A Deepness in the Sky").
No reason for a gel to resist ice shear (which wouuld be quite impossible). As I understood it, liquid water circulation under the glacier is bringing in warm seawater which is melting the ice from below. Gel that water and the circulation would stop, which would slow down the melting. It might even result in the gelled water becoming cold enough to freeze.
As for the dangers of meddling with things that aren't well-understood and which consist of lots of interlocked feedback loops, I agree. Except, we've already done that on a massive scale with atmospheric CO2. If sea level is rising seriously fast because of the melting of this area of ice, slowing or stopping the melt might be the least bad option. Especially so, if there's evidence that it was frozen all the way down in recent geological time.
There's a way to slow this process, if anyone dare try. Inject a gelling agent into the water at the bottom of these valleys, so it can't circulate to the ocean. It's amazing how small a quantity of the right material can turn water from a runny liquid into a viscous or near-solid gel. Once immobilized, it might even freeze solid.
Of interest only to a techie, but does anyone know why they've rotated the controller chip 45 degrees with respect to the others? It's not obviously making the most efficient use of PCB real estate (and neither does it look "cool", not that many people look inside the plastic case).
So how on earth did we manage to have both friends and privacy in the days before the internet existed?
Re: Mines fantastic
Or that he's reviewing one with a faulty display, and he ought to return it for a warranty replacement.
That's an expensive and silly promise for a bank to make (if they actually made it, which I doubt).
24/7 is much harder than (say) 5am to 1am six days/week, and I for one don't care if my bank is occasionally offline for planned maintenance between (say) 1am and 5am. I know that at least one of my financial services providers starts its scheduled downtimes at midnight - a bit early for my liking (which is how I know) but not enough to actually annoy me. Likewise, if they sometimes need to take a longer time-out on a Sunday, I'd not be very bothered. Certainly given a choice between 24/7 or free banking, I'd take the latter without hesitation!
U-CLOD does not begin with C
I think I spy someone who didn't get the joke?
Re: If you knew SUSY like I know SUSY...
Non-scientists often ask for a simplified, non-mathematical explanation. What they don't understand is that the two adjectives are mutually contradictory. Mathematics is the simplest language we've got for describing how the universe works.
And no, we don't know why. Maybe God is a mathematician.
Re: Is there an end point?
It's also possible to have no end-point or start-point, if time, space and any other dimensions that may exist are all cyclic.
This is not a popular viewpoint, given the overwhelming evidence that about 20 Gyears ago, the entire universe was compressed into a very matter-dense, very hot, very small and very ordered volume. We call that the big bang. Nevertheless, it's huge leap from that, to assuming that it all originated in a mathematical singularity some tiny fraction of a second earlier. That's a leap from the unknown to the fundamentally un-knowable. From something that might one day be understood by observation and deduction, to something that absolutely cannot be.
More like the non-luminiferous aether. Photons do not interact with the Higgs field, therefore remain massless, and consequentially can exist only by travelling at the speed of light. Photons (and maybe gravitons, if they exist) are the only things which do NOT disturb the Higgs field.
Not yet at enough sigmas to even justify calling it a hint. Well, that if the lines in the New Scientist graphic were the conventional length of one sigma. Hopefully they'll have a better idea before the CERN upgrade commences.
Re: "what happened before the big bang"
Actually (in theory) black holes evaporate, albeit very slowly for large ones. (In practice, we don't have any black holes that we can observe in enough detail to know). Anyway, as they evaporate they spit out photons, and so the end-point of the universe is a sea of stable particles, mostly photons, spread very thin by the expansion of space-time.
The other thing that seems to be happening is that the expansion of space-time is accelerating ("dark energy"). This is observational astronomy, not theory. This might mean that the ultimate end comes much sooner (relatively speaking - mere gigayears or terayears - tomorrow is unlikely but not impossible) when the velocity of every particle in the universe with repect to every other particle becomes greater than the speed of light. All interaction ceases, there are no events left to happen, the universe is done. Everything is past. Time, and "what happens next?", no longer have meaning.
(There's no ban in relativity on purely geometric speeds in excess of the speed of light - the framework can expand faster than the speed of light. That's why we talk of the known universe, because there may be parts of the whole universe that are receding from us at greater than the speed of light, which we'll never be able to see unless the expansion slows down or reverses).
Re: Well Duh!
> THAT is why Microsoft is moving away from the mouse, which was always a terrible input device.
Just in case you are not trolling, and haven't worked this out, despite your claimed pain.
A mouse is the only pointer device(*) that is not anchored to the rest of the hardware, and is therefore capable of being used in a way that does NOT cause muscular strain or carpal tunnel syndrome. The problem is that 9/10 users don't know how, and 9/10 won't change even when you show them how.
Take the mouse off the desktop and put it on your thigh. Learn to move the cursor with several swipes, rather than thinking you have to move it from top left to bottom right without taking it off the surface it's resting on.
This way, you can control your computer without using any muscles other than those in your fingers, until you have to switch to the keyboard. It might feel awkward at first (I can't remember). So does riding a bicycle.
(*) actually not quite true, the other option is a trackball.
Elephant in the room?
A long time ago, Microsoft ripped off an elephant -- called IBM. Supposedly, elephants never forget.
It it possible that IBM will decide the time is ripe for revenge? In the form of an IBM-supported Linux-based corporate desktop offering? They've certainly got the know-how and experience.
Personally, I'm thinking "if only". They'll never have a better chance.
> But only a moron will still be struggling after a day or two
Let's assume you're right, and say one day. That means the added cost of adopting windows is one day's salary. Multiply up. Or just think of the economic loss as being the same as a flu epidemic (regular flu, not the killer variety).
That's the downside. Now, what is the upside, that makes you happy to pay for this shoer-term loss of productivity? Upside for your organisation, that is. Not for Microsoft.
Re: Fecking Mozilla
Mozilla are one of the few that recognise the problem. What you want is the Extended Support Release of Firefox. Bugfixes only, not new features you never asked for.
Re: Who the hell cares?
One should also note that in UK vernacular (not sure about USA, Oz, etc) a boob can mean a mistake. Referencing uninitialized storage can accurately be described as a "big boob" for a programmer.
BTW, 0xB16B00B5 has been patched to 0x0DEFACED
Personally I wonder why the original wasn't 0x0B00B1E5
Re: Are you kidding me?
The number is written into "uninitialized" storage in a VM environment where uninitialized is not an option. It's useful to a programmer to have a distinctive hex pattern. If he sees that in a register after a core dump, it's a pretty good clue as to what went wrong.
These days in scientific codes, you want to have everything initialized to an IEEE Floating-point NAN pattern ("Not A Number"). Then, instead of crunching garbage up with your data if a bug references uninitialized storage, your program immediately throws a floating-point exception. ISTR NAN can also be customised to have humorous hex representations (or more boringly, to encode the address of where it came from).
Re: Oh noes 0xDEADBEEF
I believe that was also a patch to the original version which was 0xDEADBABE. That code was written at about the same time as a young lady died in a car belonging to one of the Kennedy dynasty (ie rather before my time).
Re: how much carbon is burned
Very little. The reason is that the soluble iron is like a catalyst for the plankton. It's a shortage of small amounts of iron which limits the rate at which plankton can grow. Supply those small amounts, and a massively greater weight of plankton grows, much of which is carbon. And when it dies, it sinks, taking the carbon to the ocean deeps. (Also the iron, which is WHY it's in short supply in ocean waters).
I wonder if there's a stabilizing feedback mechanism here. We're causing the oceans to become more acidic as they absorb the CO2 we emit. Will the increased acidity increase the amount od iron that the oceans can dissolve out of the dust that the winds blow from land deserts out to sea? If so, that means more plankton dragging more CO2 down to the ocean deeps.
Re: Timing is perfect!
The judge can't order Apple to change its corporate mind. The case-law implications in other jurisdictions would be the same, whether or not the judge had ordered the publicity. With respect to future Apple vs Samsung action, the publicity order is a non-issue.
Whether it'll hurt Apple's sales remain to be seen. People do not like bully-boy companies, though to what extent this will tar Apple with that brush remains to be seen. Their Teflon coat is probably good for a while yet.
Re: Spun down or Offline disk?
> Because when a disk is spun up, you notice if it's failed. When a disk is on a shelf, there is no notice, unless you spin them up every so often to check them, in which case you rapidly start to lessen and possible advantage.
I'm not convinced. Many office PCs are powered up and down daily. Many are configured to save electricity by sleeping with the disk spun down, several times per day. They're acceptably reliable. I look after ~100 such and see 2-3 HD failures per annum. With about half there's advance warning of incipient failure (SMART error counts) .
For an archive, the disks would be in RAID sets (multiple partity disks, at least two). Have the automation spin the disk up once a week if that hasn't happened by normal operations. Fail? same as any other failure in a RAID system. (Automatically) replace the failed disk, reconstruct, set bright red failed light on failed disk canister so dumb tired human knows which drive he's supposed to unplug and toss. Disk life expectancy would be close to shelf life, if they were powered up only for a couple of hours, one day in seven. MTBF ten years? Close to office PC disk life, if active two hours every day and spun up and down a few times per day. Certainly no worse than three years.
Main problem I see with a big disk archive is the running cost of replacing failed disk drives. There again, how long are tapes safe before you are advised to copy them to new media? Cost per Gbyte is pretty much the same. In a few years time, will tape have caught up with 10Tb disks? And if BPM/ HAMR tech gets out of the labs, we'll probably have 100Tb disks by 2022.
Re: Spun down or Offline disk?
> I would not trust a disk to be off for a year or more and expect it to come back
Why distrust that, any more than you distrust a disk that's powered up, wearing out some mechanical or electronic component with an in-service life considerably less than its shelf life?
Anyway, for archive you are surely using RAID techniques with multiply redundant disks, so a single failure or even a double failure won't hurt.
"New" disks may have been in the pipeline from manufacturer's testing to your installation for many months. True, new drives fail rather more often in their first few weeks and occasionally are even DOA. Most, though, are just fine. So as long as you have RAID with two or more redundant disks you should be OK.
Re: I remember a time...
Yes, it's very important to match the reliability of the storage to the importance of being able to retrieve it down the line. My CD archive is of physics data most of which will never be read again, and of which a statistical sampling (say 80% of the files) will be almost as good as 100%.
Wonder if anyone would be interested in software to create RAID-6 sets of DVDs? (Not that I have time to write it, but someone might like to run with the idea, especially if their data archiving needs are a few tens of Gb per run).
Spun down or Offline disk?
No reason to keep your archive disks powered and spinning. If access is infrequent, the system should spin them down between accesses. If even less frequent, they could be unplugged completely (robotic hot-swap SATA storage? Or just some custom electronics to cut the power completely on drives that won't be accessed again for weeks.
Arguments have raged for decades on whether drives last longer spinning or powered down. I don't expect a resolution any time soon. Whenever someone has a statistically valid answer, the drives for which it's an answer are many years obsolete.
Re: I remember a time...
Anyone know why they can't / don't do write-once optical tape? Holes burned in a stable dye layer between polymer films? 2400 feet of 1-inch tape is the area of about 1500 DVD-Rs, or about 7Tb at the same data density.
BTW I have no trouble reading CD-R's burned over a decade ago, that have been kept in sleeves in the dark at office temperature. Ditto DVD-R going back slightly less time. People who say they don't last, are probably letting sunlight get to them.
Re: Tape this !
> Cheaper TB for TB? Really?
DLT-S4 cartridge, 800Gb (1.6Tb compressed), £40
2Tb disk drive, £80 at inflated post-Thai-flood price. £50 expected again soon-ish. 4Tb drives on the market but so far at "premium" prices.
I make that a tie, depending on whether your data is already compressed or hugely inefficient. Now, if the argument was whether you'd be able to read it after twenty years' offline storage, tape might make the better case. Certainly, the results of the accelerated ageing tests for tape don't need to be taken with quite as much salt. But if the data really matters, you'll probably be reading or even re-copying every couple of years to be on the safe side of entropy.
Unscrew the socket, rotate 180 degrees, screw back in place. It's only convention that the earth pin goes at the top and the switch (if any) is "down" for on. Obviously, make sure you don't strain the mains wiring in the socket box when you do this.
Re: Cat5 and Gigabit
you want at least Cat6 for a stable gigabit network. Just like I have here at home, in fact.
Overkill. Gigabit was specified for cat-5. Experience with cat-5 in the field suggested insufficient margin to tolerate all the kinks and scrapes that the cable plant got subjected to in the field, and cat-5e was born. I doubt you can still purchase non-e plain cat-5. Cat-5e is extremely widely used for Gbit ethernet (such as everywhere in my workplace) and has no stability issues at all provided you respect the distance limits (max 94m of fixed wiring with max 6m total of patch cable at the ends, no joins in the middle. If the cable run in the middle is considerably shorter, as it usually is, you can take some liberties with longer patch cables at the ends).
Comparative tests with 2.4GHz and 5.8GHz a/b/g/n?
Pointless. Comparing apples and oranges. Comparison against other powerline networking products used with the same domestic power wiring and household appliances is at least apples with apples.
Comparison with wired Cat5e via 1Gbps Switch?
Pointless. A 1Gbps switch gives you 1Gbps end to end, and no variability from interference etc. That translates to at least 100Mbyte/sec data transfer on any sufficiently agile PC and NIC.
Effect of all the light sockets with cheap CFL lamps?
You'd need to characterize the CFL lamps. Cheap but minimally EU legal? Cheap and illegal? How illegal? Are any two bulbs even from the same batch comparable in terms of powerline interference? Do they change with ageing (I know that the gas discharge does). And if you did all this, how is a reader supposed to apply it to his random collection of mains wiring and appliances?
Frankly, buy it, try it, fiddle around with your own domestic locations and extension cables and so on if you can be bothered. It works well enough for most people. Be aware your mileage will vary from the reviewers', sometimes very much so. If you want seriously predictable and consistent network performance, install cat-5e and a switch!
Is this a problem?
Life expectancy "in excess of 100K cycles" but each cycle takes only 1us. So might it be vulnerable to burn-out within a few seconds, if someone makes a programming error? 100k x 1us = 0.1 second!
Re: fine the bustard!
Is that a joke or a spelling mistake?
(Great bustard - world's heaviest flying land bird - a bit like a flying turkey)
Re: The EC finally sorted the brower wars, after microsoft had won.
Protect Linux and multi-boot. Yes PLEASE.
I noticed that the browser choice screen had gone. Big deal. I assumed it was my employer doing something sensible, that they'd somehow removed it because it just confused users who did not have admin rights to install anything. Firefox was in the standard builds in any case.
The EU should offer to let MS off the hook in exchange for pre-emptively knocking on the head any future attempt at locking Linux out of PC hardware. Microsoft should be required to agree not to do what they aren't presently doing and claim not to be planning, with a pre-agreed fine of say ten billion Euros the moment they breach their undertaking. And if Microsoft starts wriggling, well, we'll all know what that means!
Re: Lets take it a bit farther
In the EU we have an expectation of privacy under EU law. Employers are allowed to monitor e-mail and telephone calls only if they let you know in advance that they are doing so, and it's for appropriate purposes such as financial compliance or business dispute resolution. That still doesn't mean that they can act against you if they "overhear" you say something they don't like in a conversation or e-mail to a person you call a friend. You'd have to have broken the conditions that the monitoring was put in place to enforce, and that monitoring would have to be reasonable. They'd have to be rather careful even if a now ex-friend forwarded to your employer, messages that you believed were private communications when you sent them in the first place..
But if you post in a public forum, you can't argue that you expected privacy. It's more akin to shouting in a public place (where bringing your employer into disrepute has long been held acceptable cause for disciplinary action).
The name "Twitter" conveys to me an image of immature fledgelings in a nest. They Twitter for attention. Quite often the attention they get is from a cat or magpie thinking "lunch".
Maybe also to do with censorship? The more bandwidth is available, the harder it gets to censor and filter it.
Re: Old news ...
Nice story but the physics is wrong. Oxygen and Acetylene gases are both denser than air. Such a balloon wouldn't get off the ground.
Presumably the lightest possible batteries that pack enough charge for the duration of the flight. I'd guess non-rechargeable Lithium cells. Obviously one would check that the voltage and current needed are maintained at low temperatures (or weight-budget for enough thermal insulation to prevent them getting too cold).
Re: silly questions...
Even without a parachute, the drag created by a burst weather balloon is fairly considerable. I expect that for the weight of payload that it can lift, packed into something without any sharp corners, the risk of causing serious injury is negligible even if it does land on someone's head at terminal velocity.
The odds of hitting someone with an object dropped randomly on the earth's surface are very small. There are probably more meteorites dropping to earth every year than there are weather balloons, and even a small lump of nickel-iron at terminal velocity could do serious injury or worse.
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