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User Journal

Journal Journal: Contract contract...

Let's see. Contracting can be interesting - hacking around on Solaris 10 more than is probably good for me.

And my home PC's mainboard had a capacitor blow up after 3 1/2 years of service, and turn into a smoke machine. Never thought I'd see old gear die like that.

User Journal

Journal Journal: 1-3% of all mainstream stars have planets?

The venerable BBC is reporting that a survey of light emitted from white dwarfs showed that between 1% and 3% had material (such as silicon) falling into the star on a continuous basis, potential evidence of dead worlds and asteroids. On this basis, the authors of the study speculate that the same percentage of mainstream stars in the active part of their life will have rocky matter. This is not firm evidence of actual planetary formation, as asteroids would produce the same results, but it does give an upper bound and some idea of what a lower bound might be for planetary formation.

Aside from being a useful value for Drake's Equation, the rate of planetary formation would be valuable in understanding how solar systems develop and what sort of preconditions are required for an accretion disk of suitable material to form.

Because the test only looked for elements too heavy to have been formed in the star, we can rule out the observations being that of cometary debris.

User Journal

Journal Journal: Seven Dead Men 1

I have released my first feature, Seven Dead Men, under a creative commons license. Feel free to download it off of LegalTorrents. If you would like to buy a copy, order it though google checkout and use the coupon code "slashdot" for a discount. The path to get to this point has been a long and circuitous one. If you have any questions about the process, ask away and I'll do my best to answer them.

User Journal

Journal Journal: Fireball, but not XL5 3

Four fireballs, glowing blue and orange, were visible last night over the skies of the Carolinas on the southeast coast of the United States, followed by the sound of an explosion described as being like thunder. Reports of hearing the noise were coming in from as far afield as Connecticut. There is currently no word from NASA or the USAF as to what it could be, but it seems improbable that anything non-nuclear the military could put up could be heard over that kind of distance. It therefore seems likely to be a very big meteorite.

The next question would be what type of meteorite. This is not an idle question. The one slamming into the Sudan recently was (a) extremely big at an estimated 80 tonnes, and (b) from the extremely rare F-class of asteroid. If this new meteorite is also from an F-class asteroid, then it is likely associated with the one that hit Sudan. This is important as it means we might want to be looking very closely for other fragments yet to hit.

The colours are interesting and allow us to limit what the composition could have been and therefore where it came from. We can deduce this because anything slamming through the atmosphere is basically undergoing a giant version of your basic chemistry "flame test" for substance identification. We simply need to look up what metals produce blue, and in so doing we see that cadmium does produce a blue/violet colour, with copper producing more of a blue/green.

Other metals also produce a blue glow and tables of these colours abound, but some are more likely in meteoric material than others. Cadmium exists in meteorites. Well, all elements do, if you find enough meteorites. but it exists in sufficient quantity that it could produce this sort of effect. (As noted in the chemmaster link, low concentrations can't be detected by this method, however this is going to be vastly worsened by the fact that this isn't a bunsen burner being used and the distance over which you're observing is extreme.)

Ok, what else do we know? The fireballs were also orange. Urelites, such as the Sudan impact, contain a great deal of calcium, which burns brick-red, not orange. This suggests we can rule out the same source, which in turn means we probably don't have to worry about being strafed the way Jupiter was with the Shoemaker-Levy comet (21 impacts).

What can we say about it, though? Well, provided the surviving fragments didn't fall into the ocean, it means every meteorite hunter on the planet will be scouring newspaper stories that might indicate where impacts occurred. Meteoric material is valuable and anything on a scale big enough to be heard across the entire east coast of the US is going to be worth looking for. It had split into four in the upper atmosphere, so you're probably looking at a few thousand fragments reaching ground level that would exceed a year's average pay.

User Journal

Journal Journal: feature 6

Spent the last couple of years making my first feature. Shot/wrote/edited/etc it myself on a shoe-string budget. Sent it off to a few film festivals not expecting much. The response thus far has matched my expectations. Hard to compete with people who have a thousand dollars for every one of mine.

The old saw goes it takes ten years to get good at anything. Made my first short back in 1999, keep on feeling like I'm just a single step away from breaking through. But as of yet, nothing.

And so, slogging ever onward. Been debating whether it would be a good idea to self-distribute/release the project under a CC license the same as I have with my shorts. If I sold a few dvds they would pay for the shooting if nothing else.

All I really want any more is somebody out there to watch the damn thing. And this cockamamie scheme would seem as decent as any other. Or rather, something something about doing it for the cause. Thoughts, yay or nay?

User Journal

Journal Journal: What constitutes a good hash anyway? 3

In light of the NIST complaint that there are so many applicants for their cryptographic hash challenge that a good evaluation cannot be given, I am curious as to whether they have adequately defined the challenge in the first place. If the criteria are too loose, then of course they will get entries that are unsuitable. However, the number of hashes entered do not seem to be significantly more than the number of encryption modes entered in the encryption mode challenge. If this is impossible for them to evaluate well, then maybe that was also, in which case maybe we should take their recommendations over encryption modes with a pinch of salt. If, however, they are confident in the security and performance of their encryption mode selections, what is their real objection in the hashing challenge case?

But another question one must ask is why there are so many applicants for this, when NESSIE (the European version of this challenge) managed just one? Has the mathematics become suddenly easier? Was this challenge better-promoted? (In which case, why did Slashdot only mention it on the day it closed?) Were the Europeans' criteria that much tougher to meet? If so, why did NIST loosen the requirements so much that they were overwhelmed?

These questions, and others, look doomed to not be seriously answered. However, we can take a stab at the criteria and evaluation problem. A strong cryptographic hash must have certain mathematical properties. For example, the distance between any two distinct inputs must be unconnected to the distance between the corresponding outputs. Otherwise, knowing the output for a known input and the output for an unknown input will tell you something about the unknown input, which you don't want. If you have a large enough number of inputs and plot the distance of inputs in relation to the distance in outputs, you should get a completely random scatter-plot. Also, if you take a large enough number of inputs at fixed intervals, the distance between the corresponding outputs should be a uniform distribution. Since you can't reasonably test 2^512 inputs, you can only apply statistical tests on a reasonable subset and see if the probability that you have the expected patterns is within your desired limits. These two tests can be done automatically. Any hash that exhibits a skew that could expose information can then be rejected equally automatically.

This is a trivial example. There will be other tests that can also be applied automatically that can weed out the more obviously flawed hashing algorithms. But this raises an important question. If you can filter out the more problematic entries automatically, why does NIST have a problem with the number of entries per-se? They might legitimately have a problem with the number of GOOD entries, but even then all they need to do is have multiple levels of acceptance and an additional round or two. eg: At the end of human analysis round 2, NIST might qualify all hashes that are successful at that level as "sensitive-grade" with respect to FIPS compliance, so that people can actually start using them, then have a round 3 which produces a pool of 3-4 hashes that are "classified-grade" and a final round to produce the "definitive SHA-3". By adding more rounds, it takes longer, but by producing lower-grade certifications, the extra time needed to perform a thorough cryptanalysis isn't going to impede those who actually use such functions.

(Yes, it means vendors will need to support more functions. Cry me a river. At the current scale of ICs, you can put one hell of a lot of hash functions onto one chip, and have one hell of a lot of instances of each. Software implementations are just as flexible, with many libraries supporting a huge range. Yes, validating will be more expensive, but it won't take any longer if the implementations are orthogonal, as they won't interact. If you can prove that, then one function or a hundred will take about the same time to validate to accepted standards. If the implementations are correctly designed and documented, then proving the design against the theory and then the implementation against the design should be relatively cheap. It's crappy programming styles that make validation expensive, and if you make crappy programming too expensive for commercial vendors, I can't see there being any problems for anyone other than cheap-minded PHBs - and they deserve to have problems.)

User Journal

Journal Journal: Beowulf MMORGs 3

Found this interesting site, which is focussing on developing grid computing systems for gaming. The software they seem to be using is a mix of closed and open source.

This could be an important break for Linux, as most of the open source software being written is Linux compatible, and gaming has been the biggest problem area. The ability to play very high-end games - MMORGs, distributed simulators, wide-area FPS, and so on, could transform Linux in the gaming market from being seen as a throwback to the 1980s (as unfair as that is) to being considered world-class.

(Windows machines don't play nearly so nicely with grid computing, so it follows that it will take longer for Microsoft and Microsoft-allied vendors to catch up to the potential. That is time Linux enthusiasts can use to get a head-start and to set the pace.)

The question that interests me is - will they? Will Linux coders use this opportunity of big University research teams and big vendor interest to leapfrog the existing markets completely and go straight for the market after? Or will this be seen as not worth the time, the same way that a lot of potentially exciting projects have petered out (eg: Open Library, Berlin/Fresco, KGI, OpenMOSIX)?

User Journal

Journal Journal: The Lost Tapes of Delia Derbyshire

Two hundred and sixty seven tapes of previously unheard electronic music by Delia Derbyshire have been found and are being cataloged.

For those unfamiliar with Delia Derbyshire, she was one of the top pioneers of electronic music in the 1950s and 1960s. One of her best-known pieces was the original theme tune to Doctor Who. According to Wikipedia, "much of the Doctor Who theme was constructed by recording the individual notes from electronic sources one by one onto magnetic tape, cutting the tape with a razor blade to get individual notes on little pieces of tape a few centimetres long and sticking all the pieces of tape back together one by one to make up the tune".

Included in the finds was a piece of dance music recorded in the mid 60s, examined by contemporary artists, revealed that it would be considered better-quality mainstream today. Another piece was incidental music for a production of Hamlet.

The majority of her music mixed wholly electronic sounds, from a sophisticated set of tone generators and modulators, and electronically-altered natural sounds, such as could be made from gourds, lampshades and voices.

Christmas Cheer

Journal Journal: for those of you not on multiply... 4

boyfriend of tuxette and I graded successfully to P5 in Krav Maga on Thursday. Next up is G1 and we won't be allowed to grade to that for at least another year :-)
User Journal

Journal Journal: Well, this is irritating. 3

Someone has trawled through YouTube and flagged not only the episodes of The Tripods, but also all fan productions, fan cine footage and fan photography of the series. How so, can't you buy it on DVD? Only the first season, the second exists only in pirated form at scifi conventions, and of course the fan material doesn't exist elsewhere at all. The third season, of course, was never made, as the BBC had a frothing xenophobic hatred of science fiction at the time. (So why they made a dalek their general director at about that time, I will never know...)

What makes this exceptionally annoying is that the vast bulk of British scifi has been destroyed by the companies that produced it, the vast bulk of the remainder has never seen the light of day since broadcast, and the vast bulk of what has been released has been either tampered with or damaged in some other way, often (it turns out later) very deliberately, sometimes (again it turns out later) for the purpose of distressing the potential audience.

I've nothing against companies enforcing their rights, but when those companies are acting in a cruel and vindictive fashion towards the audience (such as John Nathan Turner's FUD of audiences being too stupid to know what they like, or too braindead to remember what they have liked), and the audiences vote with their feet, on what possible grounds can it be considered justified for those companies to (a) chain the audience to the ground, and (b) then use the immobility of the audience to rationalize and excuse the abuse by claiming the audience isn't going anywhere?

I put it to the Slashdot Court of Human/Cyborg Rights that scifi fans are entitled to a better, saner, civilized explanation, and that whilst two wrongs can never make a right, one wrong is never better.

Christmas Cheer

Journal Journal: wheeeee!

Just so I can boast about it here as well... I'm going to Svalbard next week! :-D

For business. But still...

Linux Business

Journal Journal: update for those of you who aren't on Multiply 7

Let's see...

- The new job (started 3rd of March) is going OK though there are still quite a lot of adjustment pains. At the very least I have close to a carte blanche when it comes to going to external courses and conferences, which is quite cool.

- It's finally warm enough to start running outside. Yay!

- Still doing Krav Maga. Some of you know I missed out last semester due to an injury, but now everything seems to be OK. I'm not sure if I'll go up to P5 this semester though.

- I met an ex-slashdotter/Multiply refugee in real life, making the total to three.

- I've been taking lots of bird photos lately, but I really need to learn how to use my camera properly. It's good to know I'm not short on subjects :-)

- I have mod points :-D

How are you all doing?

User Journal

Journal Journal: 1nm transistors on graphene

Well, it now appears the University of Manchester in England has built 1nm transistors on graphene. The article is short on details, but it appears to be a ring of carbon atoms surrounding a quantum dot, where the quantum dot is not used for quantum computing or quantum states but rather for regulating the electrical properties. This is still a long way from building a practical IC using graphene. It is, however, a critical step forward. The article mentions other bizare behaviours of graphene but does not go into much detail. This is the smallest transistor produced to date.

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The rule on staying alive as a forecaster is to give 'em a number or give 'em a date, but never give 'em both at once. -- Jane Bryant Quinn

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