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Open Source

Video The MinnowBoard is a Low-Cost, Open Hardware Single-Board Computer (Video) 84

Out in the Northeast Texas town of Ft. Worth, a company called CircuitCo started making something they called the BeagleBoard -- an open source hardware single-board computer for educators and experimenters. Now, with help and support from Intel, they're making and supporting the Atom-based MinnowBoard, which is also open source, and comes with Angstrom Linux to help experimenters get started with it. David Anders is the Senior Embedded Systems Engineer at CircuitCo. Slashdot's Timothy Lord met David at LinuxCon North America 2013 in New Orleans and made this video of him talking about the recently-released MinnowBoard and the more mature BeagleBoard.

Comment I think I know what this is about. (Score 3, Informative) 142

The article says they have spent 6 years researching the technology. 6 years ago is also when German researchers published their discovery: http://en.wikipedia.org/wiki/Hydrothermal_carbonization (The German version of the Wikipedia article is much more informative.)

As far as I know, it started with a researcher wondering how exactly the Earth produced coal and oil and discovering that for almost a century nobody had done any new experiments. So he did some, adding some of today's knowledge.

It turns out that if you put water and basically arbitrary organic waste (wood, grass cuttings, leaves, entire weeds, whatever) into a pressure cooker, add some citric acid as a catalyser and then heat it to 200 degrees Celsius, then you get an exothermic reaction which makes the stuff keep that temperature without further input of energy. Provided you are not using an ordinary pressure cooker (which will explode) but some special thingy.

You stop the reaction after 8-12 hours and filtrate the water to get the product. Depending on the precise time you stop, you can create topsoil, oil, brown coal or low-quality stone coal. While the method doesn't seem to produce any excess heat, you can theoretically make an industrialised country CO2 neutral by treating all of its green waste that way and storing the resulting low-quality coal underground, e.g. in an old coal mine.

Comment It was the Germans' fault. (Score 3, Informative) 258

As Gutenberg was German, the first printing presses only had letters as required for German. Discarding the umlauts from the printing presses imported from Germany was easy, but creating new letter types for eth and thorn was tricky. An initial workaround for eth was to use y because in certain handwritings the two looked similar. Later they used th for both eth and thorn.

Comment Re:Units in the summary (Score 1) 307

Well, yes, there are times when I have to use the system of measurement used by roughly 5 % of the world population rather than the one used by the other 95%. But there shouldn't be so many of these occasions.

Just like a news report in the US should not assume familiarity with the Spanish language just because it's the mother tongue of 12 % of the US population.

Comment Little known fact about whaling (Score 5, Interesting) 311

It's not really about whales or their meat. It's about oil and similar resources.

According to international treaties, under certain conditions a country has the right to drill for oil in a certain area if it has traditionally and recently been exploiting the area economically in other ways. This explains a few things about the Japanese whaling programme that would make no sense otherwise. Why they are doing this even though they have no need for the meat, as the article makes clear. But also why they are not making a better effort to disguise the whaling as scientific. Sure, they are arguing before the IWC that it's primarily scientific. But sooner or later they will have to argue before a different body that it's primarily economic, and has always been so. The more obviously economic the programme is, the better it is for their purpose, so long as they can get away with it before the IWC.

Comment Re:Impossible? (Score 5, Informative) 192

Who would have thought that the f... article addresses this devilishly ingenious workaround?

"And even if Eve steals the glass, they estimate that it would take her at least 24 hours to extract any relevant information about its structure.

This extraction can only be done by passing light through the glass at a rate that is limited by the amount of heat this creates (since any heating changes the microstructure of the material). And the time this takes should give the owners enough time to realise what has happened and take the necessary mitigating actions."

Comment Re:Relative of the tomato??? (Score 1) 116

Obviously you (the authors) are not to blame for this. In the original article everything was in the proper context. But the author of the report in Science should have explained what bladderworts are like and instead ran away with a misunderstood bit of information ripped out of context. *This* is what provoked comments such as "Where pray tell then are the GM tomatoes that eat aphids?" and references to killer tomatos. (Of course, otherwise we might have been speculating instead on how many of you gave their lives for science during this research. Carnivorous plants are still a man-bits-dog topic, after all.)

Comment Relative of the tomato??? (Score 3, Informative) 116

That claim is seriously misleading. According to Wikipedia, the closest connection between the bladderwort and the tomato seems to be that both are asterids of clade euasterids I. As are all other solanaceae besides tomatos (e.g. potatos, tobacco, petunias), all other lamiales besides bladderwort (e.g. acanthus, olives, plantains - the little green plants not the bananas, verbena) and many other plants such as forget-me-nots or gentiana. Initially they even got the time of the evolutionary split wrong by a factor of 1000!

I guess the truth is that the tomato genome is exceptionally well known and the two species are close enough to make a comparison reasonable. And to quote from the actual original article's abstract: "Unexpectedly, we identified at least three rounds of WGD [whole genome duplication] in U. gibba since common ancestry with tomato (Solanum) and grape (Vitis)."

Comment Re:0.001km = 0.01hm = 1m = 10dm = 100cm = 1000mm (Score 1) 909

Nope.

1/25 is a big improvement because it's 4/100, with the 100 on the metric side -- where it doesn't matter (4 in = 1/3 ft = 100 mm = 10 cm = 1 dm).

There is nothing wrong with calling 1/2 litre a metric pint if it facilitates your sense of the amount, just like 1/2 kg is a metric pound. The metric system doesn't force you to dramatically change unit sizes, it just urges you to adapt them a little bit to get round numbers. So the following further response doesn't even matter:

1 litre sizes are more commonly seen in German shops than 2 litres or 1/2 litre. I guess that's in part because we still have lots of inner cities where people walk to for shopping, in part because glass bottles are still relatively popular, and in part because we are not being supersized. The most common sizes here are 1 litre tetrapaks and glass bottles for milk, juice and wine, 0.7 litres and 3/4 litre for mineral water (glass/plastic bottles) and 1 1/2 litre plastic bottles for lemonades. 1/2 litre and 330 ml (roughly 1/3 litre) are also common, but only because they are virtually the only unit size for (glass) bottles of beer. The unit in which beer is sold in Munich at Oktoberfest, called the "Maß", was 1.069 litres before metrication and is precisely 1 litre now. Otherwise the most common drink sizes in restaurants are 0.2 litres, 0.3 litres and 0.4 litres. 2 litre bottles are extremely rare here.

"1 liter bottles of anything are unloved orphans -- too big for one serving, but not big enough for the leftovers to even be worth saving."

I can't tell you how happy I am that I am neither your balance nor your rubbish container. And that there is still such a thing as a family meal without TV here, for which 1 litre of apple juice, 3/4 litres of carbonated mineral water and 1 litre of beer seems about right in the case of 2 adults and 2 children.

Comment Re:Did you actually check the law? (Score 1) 909

Many months ago I actually read a lot of laws and documents published by various national standardisation bodies in order to get to the bottom of the mass/weight/pound problems. But I did this in connection with specific discussions, not scientifically. I vaguely remember reading the UK's W&MA 1985 and noting that it specifies explicitly that the pound is a unit of mass. Apparently I missed, or later forgot, that this act distinguishes between mass and weight in the same way that physicists do. I believe that's a relatively recent development. I believe the W&MA 1976 only uses the words "mass" and "weight" in the form "mass or weight", so treats them as synonyms in the sense of the act. I guess this was an intermediate step towards making the distinction, probably reflecting a gradual change of approach.

I have also re-read the US' Mendenhall Order of 1893 now. It also referred explicitly to mass. So I definitely stand corrected as far as usage of "mass" and "weight" in recent key legislation of the US and UK is concerned.

I am still pretty sure that historically only mass featured in UK law, but was called weight. But apparently that was earlier, probably until early 19th century or so.

Comment Re:0.001km = 0.01hm = 1m = 10dm = 100cm = 1000mm (Score 1) 909

It's a shame Ben Franklin and Thomas Jefferson couldn't have talked the French into a compromise & gotten them to define 1mm as being exactly 1/24th of an imperial inch.

More likely 1/25th, which is more in the spirit of the metric system and closer to what we have. But at the time nobody expected that the Americans of all people would be so mad as to hold out against the metric system longer than everybody else. Part of the appeal of the metric system came from the fact that it was a completely new system and derived from things that everybody could connect with - such as the length of the equator for the metre. If they had wanted to compromise this, there were a numer of other systems that they might have wanted to connect with instead.

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