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Comment Re:Will it be practical? (Score 1) 142

EM waves have frequency and polarization and phase. Their "orbital angular momentum" is some combination of these parameters so you can't increase bandwidth over what can be done using some combination of these.

Actually, I don't think their OAM is a combination of those parameters. It's about the spatial distribution of the phase around the axis of transmission.

Comment Re:Here is a paper on this (Score 1) 142

It's using the spatial variation of the signal. In cylindrical coordinates (r,theta,z) aligned with the axis of transmission z, it uses different phases at different thetas. In particular, a bunch of superposed signals each with phase varying around the z axis as cos(i*theta) for i=0,1,2,... should stay conveniently distinct from transmitter to receiver.

I think the axis of transmission is baked into the idea pretty deeply - it's inherently unidirectional. I also think it's not robust to superposition: another such bunch of signals passing obliquely across the receiver would mess everything up.

Technology

Ask Slashdot: Shortcuts To a High Tech House 281

First time accepted submitter phaedrus9779 writes "I'm a recently married man about to take on the next big adventure: home ownership! I came across a great house in a great community but I need a little bit extra: a high tech house. The problem: money, I'm on a budget. I'd love to have home theaters, super high tech weather stations and iPads seamlessly installed in all the walls — but this just isn't possible. So my question to the Slashdot community is: how can I build a high tech house that will be the envy of my friends, provide lots of useful gadgets, and not break the bank? Also, as always, the cooler the better!"

Comment Re:Too many qualifiers (Score 3, Interesting) 469

The Prius Lane Keep Assist feature does steer a bit, gently - the wheel tends to drift toward it's best guess of the center of the lane. It won't drive for you, though: if you take your hands off the wheel it notices (I think it notices the absence of any applied torque over some reasonably short interval), sounds an alarm and turns off the feature.

Comment Copyright? (Score 1) 94

"Images may not be copied or offloaded, and the images and their texts may not be published. All digital images of the Oxyrhynchus Papyri are © Imaging Papyri Project, University of Oxford. The papyri themselves are owned by the Egypt Exploration Society, London. All rights reserved."

They want help transcribing these documents, but don't want anyone to keep copies of the images? How rude.

The Courts

Yahoo! Liable In Italy For Searchable Content 145

h3rr d0kt0r writes "A recent decision of an Italian court could spark considerable discussion over the liability of a search engines. The court actually ordered Yahoo! to remove any link to any site containing unlawful copies of a movie. Under EU Directives 2003/31, liability of search engines is not regulated (save for caching activities). In the case brought to court regarding the film About Elly, it was not the caching activities of Yahoo! that were questioned (or any content hosted on Yahoo!'s servers), but the mere fact that searching for the film made it possible to reach websites allowing the streaming or downloading of the movie (actually, illegal sites got a better ranking then the official one)."
Image

Students Banned From Bringing Pencils To School Screenshot-sm 426

mernilio writes "According to UPI: 'A Massachusetts school district superintendent said a memo banning sixth graders from carrying pencils was written without district approval. North Brookfield School District interim Superintendent Gordon Noseworthy said Wendy Scott, one of two sixth-grade teachers at North Brookfield Elementary School, did not get approval from administrators before sending the memo to all sixth-grade parents, the Worcester Telegram & Gazette reported Thursday. The memo said students would no longer be allowed to bring writing implements to school. It said pencils would be provided for students in class and any students caught with pencils or pens after Nov. 15 would face disciplinary action for having materials 'to build weapons.'"
Image

Garlic Farmer Wards Off High-Speed Internet Screenshot-sm 475

DocVM writes "A Nova Scotia farmer is opposing the construction of a microwave tower for fear it will eventually mutate his organic garlic crop. Lenny Levine, who has been planting and harvesting garlic by hand on his Annapolis Valley land since the 1970s, is afraid his organic crop could be irradiated if EastLink builds a microwave tower for wireless high-speed internet access a few hundred meters from his farm."
Government

Congress Mulls Research Into a Vehicle Mileage Tax 792

BJ_Covert_Action writes to let us know that an Oregon congressman has filed legislation to spend $154.5M for a research project into tracking per-vehicle mileage in the US, and asks: "Do we really want the government to track our movement and driving habits on a regular basis?" "US Representative Earl Blumenauer (D-Oregon) introduced H.R. 3311 earlier this year to appropriate $154,500,000 for research and study into the transition to a per-mile vehicle tax system... Oregon has successfully tested a Vehicle Miles Traveled fee... the [Oregon] report urged a mandate for all drivers to install GPS tracking devices that would report driving habits to roadside RFID scanning devices." Here is the bill (PDF). The article notes that the congressman's major corporate donors would likely benefit with contracts if such a program were begun.
Hardware Hacking

Getting a Classic PC Working After 25 Years? 533

tunersedge writes "Yesterday I dug out of my parents' basement a PC they had bought brand new in 1984: Epson Equity I personal computer; 512K RAM; 82-key keyboard; 2 (count 'em!, 2) 5.25" floppy disk drives; 13' RGB monitor (with contrast/brightness knobs); handy on/off switch; healthy 25-year-old yellowed plastic; absolutely no software. (My mom ran a pre-school, and they used it to keep records and payroll. I cut my programming teeth on this thing. GW-Basic was my friend. Kings Quest screens took 2 minutes to load when you walked into a new one.) When I resurrected this machine I pulled the case off, dusted out a little, and plugged it in. It actually fired up! I'm stoked, except the disks we had are missing. What I'm looking to do is either buy some old working disks with whatever I can find (MS-DOS 3.22, GW-Basic, whatever), or try and recreate some using a USB-based floppy drive and some modern software. Has anyone tried to resurrect a PC this old before?"
The Internet

Experimental Fees Settle Royalty War For Internet Radio 270

S-100 writes "SoundExchange has reached an agreement for royalty rates with a consortium of Internet radio broadcasters. The parties are ecstatic that the issue is finally resolved, and that the new rates are below the previous 'death to Internet radio' levels that had previously been imposed by the CARB. According to NewsFactor, Pandora founder Tim Westergren proclaims that 'the royalty crisis is over!', and other large broadcasters are equally pleased. One unheard-from group is less likely to be pleased: small Internet radio broadcasters. Buried in the details are a new minimum royalty payment: $25,000 per year. So say goodbye to all of the small Internet radio stations that you have been listening to, as they will no longer afford to operate legally."
The Military

US, Russia Reach Nuclear Arsenal Agreement 413

Peace Corps Library writes "The United States and Russia, seeking to move forward on one of the most significant arms control treaties since the end of the cold war, announced that they had reached a preliminary agreement on cutting each country's stockpiles of strategic nuclear weapons, effectively setting the stage for a successor to the Strategic Arms Reduction Treaty (Start), a cold war-era pact that expires in December. Under the framework, negotiators are to be instructed to craft a treaty that would cut strategic warheads for each side to between 1,500 and 1,675, down from the limit of 2,200 slated to take effect in 2012 under the Treaty of Moscow (PDF) signed by President George W. Bush. The limit on delivery vehicles would be cut to between 500 and 1,100 from the 1,600 currently allowed under Start. Perhaps more important than the specific limits would be a revised and extended verification system that otherwise would expire with Start in December. The United States currently has 1,198 land-based intercontinental ballistic missiles, submarine-based missiles and bombers, which together are capable of delivering 5,576 warheads, according to its most recent Start report in January, while Russia reported that it has 816 delivery vehicles capable of delivering 3,909 warheads. 'We have a mutual interest in protecting both of our populations from the kinds of danger that weapons proliferation is presenting today,' said President Obama."

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