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Interstellar Ark 703

xantox writes "There are three strategies to travel 10.5 light-years from Earth to Epsilon Eridani and bring humanity into a new stellar system : 1) Wait for future discovery of Star Trek physics and go there almost instantaneously, 2) Build a relativistic rocket powered by antimatter and go there in 22 years by accelerating constantly at 1g, provided that you master stellar amounts of energy (so, nothing realistic until now), but what about 3): go there by classical means, by building a gigantic Ark of several miles in radius, propulsed by nuclear fusion and featuring artificial gravity, oceans and cities, for a travel of seven centuries — where many generations of men and women would live ? This new speculation uses some actual physics and math to figure out how far are our fantasies of space travel from their actual implementation."
Hardware Hacking

Submission + - How to improve a water distribution system?

ildefonso writes: Hi!

I live in an small community which have a "rural" aqueduct, and I would like to improve it. Currently, it is just a pipe from the river to a tank, and a 2" pipe down the mountain and 1/2" pipes to each house. In summer time, when water starts to fail, they close the main valve in order to allow the tank to fill, and then open again for some time. But due to the lack of some kind of control, when the main valve is open, the only houses that receive water for a long time are the ones that are at the lowest height, the ones that are higher receive water for a short period of time, and sometimes doesn't receive anything at all.

Anyway, here are my ideas:

My "normal" idea: I think that if I add some valves at different heights and adjust them correctly, I can get an improvement in the fairness of water distribution.

Now, my geek idea (sorry, it can't be helped, I'm a geek): I have also thought about adding volumetric flow meters to each house, and have an automatic cut-off valve, centrally controlled, to cut the water when the house have consumed it's daily quota.

The system could be implemented using a ZigBee mesh (geek), or an RS-485 network (not so geek) and some hardware that is not so expensive (around US$20-US$30 electronics per device), but if you add each of the about 500 houses, then you have big bucks, I can go with the electronic design and building myself, but I don't have enough knowledge as to choose valves, flow meters, and that kind of stuff.

My geek solution can lead to a "never-ending" supply of water to the houses that save water, but can probe to be expensive, even by building the system myself.

I would appreciate any suggestion on how to improve a water distribution system. (yes, even the fun ones). Also, any opinion on my normal and geek idea, is also welcome.

Thanks in advance,

Ildefonso Camargo

Submission + - Einstein's twin paradox resolved

slashthedot writes: "An Indian American scientist Subhash Kak from Louisiana State University has resolved the 100+ years old Einstein's twin paradox. "The fact that time slows down on moving objects has been documented and verified over the years through repeated experimentation. But, in the previous scenario, the paradox is that the earthbound twin is the one who would be considered to be in motion — in relation to the sibling — and therefore should be the one aging more slowly. Einstein and other scientists have attempted to resolve this problem before, but none of the formulas they presented proved satisfactory. Kak's findings were published online in the International Journal of Theoretical Science, and will appear in the upcoming print version of the publication."
"The implications of this resolution will be widespread, generally enhancing the scientific community's comprehension of relativity. It may eventually even have some impact on quantum communications and computers, potentially making it possible to design more efficient and reliable communication systems for space applications." -lpr021407.php"

Submission + - The *REAL* facts of Linux vs Windows ?

yorugua writes: From the report: "Considering the publicity that has surrounded — and, despite super new security-focused Service Packs, continues to surround — Windows security issues, Microsoft's determination to demonstrate that Linux is less secure than Windows shows a certain chutzpah. The company has however had some support here; Forrester, for example, provides some numbers that can be used to support the contention that Microsoft flaws are less severe, less numerous and fixed faster. And although there's a general readiness among users to believe that Windows is a security disaster area, there's also a reasonable amount of support for the view that Linux would get just as many security issues if it had anything like Windows' user base.". PDF available at indows_vs_linux.pdf . Let the flam^H^H^H^Hdiscussion begin.

Suppressed Report Shows Cancer Link to GM Potatoes 325

Doc Ruby writes "After an 8-year-long court battle, Welsh activists have finally been allowed to released a Russian study showing an increased cancer risk linked to eating genetically modified potatoes. While the victory of the Welsh Greenpeace members in the courtroom would seem to vindicate the work of the Russian scientists that did the original research, there are still serious questions to be answered. The trials involved rats being fed several types of potatoes as feed. The rats who were fed GM potatoes suffered much more extensive damage to their organs than with any other type; just the same, serious questions remain about the validity of the findings. The Welsh group wants to use this information to stop the testing of GM crops in the UK, tests currently slated for the spring of this year."

Creating Power From Wasted Heat 186

Roland Piquepaille writes "Today, about 90 percent of the world's electricity is created through an indirect and inefficient conversion of heat. It is estimated that two thirds of the heat used by thermoelectric converters are wasted and released. But now, researchers from the University of California at Berkeley have found a new way to convert this wasted heat into electricity by trapping organic molecules between metal nanoparticles. So far, this method of creating electricity creation is in its very early stage, but if it can scale up to mass production it may lead to a new and inexpensive source of energy."

Asteroid Highlighted as Impact Threat 297

Maggie McKee writes "The asteroid Apophis has been traversing the void of space for untold years; in just a few decades time it will make a very close pass to Earth, and could make an unwelcome stop on our planet's surface. Even still, it's nothing to get too worked up about. The 20-million-tonne object has a 1 in 45,000 chance of hitting the Pacific Ocean in early April of 2036. If it did hit, it could trigger a tsunami that would do an untold amount of damage to the California coastline and many other places on Earth. Despite the low level of the threat, it's still a real enough danger to prompt the United Nations to develop a protocol about the scenario. We'll get a closeup look at the object in 2029, and at that point we should have a better idea of what 2036 will bring us."

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Technological progress has merely provided us with more efficient means for going backwards. -- Aldous Huxley