Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror

Comment Re:How will I cut my grass? (Score 1) 869 869

I don't know how practical a solar powered lawn mower would be. Putting a 100 watt panel on a modified push mower would probably be pushing it, and unless you live in an area with no obstructions (trees, houses, etc) the best you can probably hope for is 18% capacitance (8 hours generation, blocked half the time, no weather considerations). If my back of the napkin calculations are right that would only be about 2 kwh every two weeks. I think your average battery powered mower has a battery pack somewhere north of 3kwh. Assuming all of these quick stats are correct its only going to be able to mow your lawn once every 3 weeks or more. Its possible that you could tweak a few things (lighter construction, lightweight blades, etc) but there are going to be some significant limitations.

Comment Just test it in space already (Score 1) 502 502

Put it on a cheap and simple satellite, piggyback it on another satellites launch and run it for a few months/years. From what I understand this thing has such a small thrust that its difficult to differentiate between any possible thrust and instrument noise (earthquakes, cars/trains driving by, magnetic fields, etc). A real world test where a craft with no other means of propulsion can/can't change its orbit is the only way to be sure.

Comment Re:What!? (Score 1) 157 157

Judges aren't supposed to really utilize either of those, at least not directly. Their job is supposed to be accurately and independently apply the law. The only way in which they exercise morality and ethics is to make sure they don't have a conflict of interest. In this case she seems to be using the most insane interpretation possible, that no one has the ability to challenge these "warrants" (they appear to function much like subpoenas). Which was probably the intent all along, to try to find a loophole whereby the government could go on fishing expeditions while not needing to deal with any of those pesky things like surviving court challenges or offering any real justification. The case may have even been introduced in a district where they knew the judges were sympathetic to their intentions, kind of like how most patent cases take place in an unpleasant little area of Texas where don't you know, patent holders are virtually always favored.

Comment What!? (Score 2) 157 157

So Facebook is receiving the warrant, it is for information on their systems, they are legally obligated to fulfill it and yet they don't have "standing" to challenge it. This judge must have failed most of her coherent arguments classes back in law school, this decision is just plain idiotic.

Comment Dont know if it counts (Score 1) 617 617

Seeing as one it was software, and two its no longer being used I don't know if it counts but for what its worth.... A few years back I was working for a county utility department, they had some ancient DOS based asset tracking database program that would barely run on Windows XP with a bunch of compatibility settings. The thing had to have been pre Windows 3.1. Computers were starting to get upgraded to newer OSs that would in no way run it so I was tasked with migrating it into a Microsoft Access database (I know, not much of a step up). Wasn't too difficult since thankfully it exported to some fairly well formatted CSV files, hardest part was breaking some of the information out into proper field formats which took a little creative work with wildcards and Excel/Open Office.

Comment Reaction mass? (Score 1) 120 120

I realize that moving the power source off of the craft is going to help some but isn't THE major problem in the rocket equation reaction mass? Rockets have to carry it with them and this craft seems no different. Unless this propulsion system produces much higher exhaust velocities I don't see how its going to help much.

Comment Re:ridiculous (Score 1) 183 183

Not that this specific technique won't need extensive testing, but chances are that on occasion you've already driven on a road using plastics as a base material. Geofoam is regularly used in road projects throughout the world.

https://en.wikipedia.org/wiki/...
http://www.komonews.com/news/l...

Comment Might work (Score 1) 183 183

If plastics which would otherwise go into a landfill or are already contaminating the environment can be used, if it has similar/better performance characteristics to traditional road materials and if its is a similar/cheaper in price then of course. But there are a lot of ifs in there.

Comment Re: Maybe... (Score 3, Interesting) 334 334

No doubt government is always attempting to co-opt the press to portray only what makes them look good and they have been successful to a degree. But the various leaks, corruption/waste stories and abuse of power pieces over the last decade or so have show that there are some holdouts that scoff at the government line. Also to a degree the internet has taken over for some of the "shaming" of "oppressive officers" that was once predominantly taken care of the press, with blog stories, Debt clocks & internet video/audio.

Comment Re: Maybe... (Score 5, Insightful) 334 334

The press in its various forms (blogs, newspapers and some filmmakers) are the defense attorneys of a free country. The Founding fathers wrote at length how the press and freedom of speech on its own was one of the major impediments to a government sinking into corruption & totalitarianism.

"The last right we shall mention regards the freedom of the press. The importance of this consists, besides the advancement of truth, science, morality, and arts in general, in its diffusion of liberal sentiments on the administration of Government, its ready communication of thoughts between subjects, and its consequential promotion of union among them, whereby oppressive officers are shamed or intimidated into more honourable and just modes of conducting affairs."
            Continental Congress, 1774

This woman isn't some random person hanging out with "scum", she's an award winning documentary filmmaker. She also helped create the Freedom of the Press Foundation. Unfortunately the press has to hang out with various groups of morally/legally questionable people in order to get to what is important, most of those people reside in our various halls of government.

Comment "Authors and Investors" (Score 2) 178 178

"To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."

Key words spelled out right in the constitution at least here in the US are "Authors and Inventors" and "limited Times", both of which appear to be FAR beyond the veil here. The artists have been dead since 1946 and no one with their head screwed on straight wound consider over a hundred and twenty years to be a "limited time" especially when you take into account that at the time the constitution was written you considered yourself lucky if you lived into your 40s.

Comment hopefully just a proof of concept (Score 1) 53 53

Hopefully this thing is just a proof of concept, any such system should be able to capture multiple pieces of debris whereas this this thing seems physically limited to capturing a single piece of debris and deorbiting. That simply is impractical with over 19k pieces of debris over 3.9 inches in size to launch a satellite for each and every one. Even if each satellite had the fuel and storage to capture 100 pieces of debris that would be around 190 satellites. A better concept might be to have a couple dozen LARGE satellites (Delta IV or Falcon Heavy) in different orbits each with a dozen or so retrieval craft that go out and collect a few pieces of debris and then return to the mother satellite and drop off their debris and refuel for another trip. After the mother satellite is either out of fuel or full of debris it deorbits itself along with its retrieval craft.

Comment Re:Long shot (Score 1) 87 87

I may be reading from some overly cheerful sources but from what I understand the air cooler system was the only real technological hurdle needed to make the SABRE engine viable and it's been tested and proven. No doubt a full prototype engine will need to be built and flown to confirm the engines performance characteristics and viability but beyond that it appears to be "simple" aircraft design/development. Expensive no doubt, but not all that different from developing an advanced airliner which are usually in the $10-15 Billion range.

Comment Long shot (Score 1) 87 87

Who knows, maybe they'll be able to get Skylon up and flying. If that happens they'll be giving rides to the rest of the space-fairing nations. A long shot I know, but beyond SpaceX it is the only fully reusable orbital launch system in some form of active development that has some physical hardware built and tested and no fancy new "10 years out" technological requirements.

UNIX is many things to many people, but it's never been everything to anybody.

Working...