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Comment Re:F2FS is not for SSDs (Score 3, Informative) 120

No, F2FS is not meant for bare NAND and doesn't do wear-levelling. It is meant for cheap flash media such as USB flash drives, SD cards, eMMC and such. Those devices have controllers that perform wear-levelling and other flash-translation layer functions. They present as block devices just like SSDs and regular hard drives. Conventional filesystems such as ext4 are optimized for spinning-rust and have to manage things like the fact that random access takes a significant amount of time while it has to wait for the next sector to come underneath the read/write head. With flash media, the seek time is zero but erasing a block takes a long time. There are of course many other differences. F2FS is designed to exploit the advantages of flash media and cope with the disadvantages. That said, I don't think I'd want to run F2FS on an SSD. SSDs have sophisticated controllers that try to compensate for the advantages and disadvantages of flash media with respect to conventional filesystems. I think you'd wind up with F2FS fighting it out with the SSD controller and I think perform would suffer as a consequence.

Pumpkin Pie increases Male Sex Drive 173

Dr. Alan Hirsch, Director of Chicago's Smell and Taste Treatment and Research Center, says the key to a man's heart, and other parts, is pumpkin pie. Out of the 40 odors tested in Hirsch's study, a mixture of lavender and pumpkin pie got the biggest rise out of men ages 18 to 64. That particular fragrance was found to increase penile blood flow by an average of 40%. "Maybe the odors acted to reduce anxiety. By reducing anxiety, it acted to remove inhibitions," said Hirsch.
Open Source

Open Source OCR That Makes Searchable PDFs 133

An anonymous reader writes "In my job all of our multifunction copiers scan to PDF but many of our users want and expect those PDFs to be text searchable. I looked around for software that would create text searchable pdfs but most are very expensive and I couldn't find any that were open source (free). I did find some open source packages like CuneiForm and Exactimage that could in theory do the job, but they were hard to install and difficult to set up and use over a network. Then I stumbled upon WatchOCR. This is a Live CD distro that can easily create a server on your network that provides an OCR service using watched folders. Now all my scanners scan to a watched folder, WatchOCR picks up those files and OCRs them, and then spits them out into another folder. It uses CuneiForm and ExactImage but it is all configured and ready to deploy. It can even be remotely managed via the Web interface. Hope this proves helpful to someone else who has this same situation."

Low-Level Format For a USB Flash Drive? 252

Luyseyal writes "I unwittingly bought one of these terrible flash cards at Fry's and have managed to nuke two of them, successively. I have a USB flash card reader that will read/write the current one at USB 1.0 speed, but it locks up every Ubuntu and XP machine I've come across in high-speed access mode. I have read that if I low-level format it that it could be fixed, though my current one doesn't support it. My Google-fu must be weak because I cannot seem to find a USB flash reader that specifies that it will do low-level formatting." Can anyone offer advice for resurrecting such drives?
Open Source

Open Source Developer Knighted 101

unixfan writes "Georg Greve, developer of Open Document Format and active FOSS developer, has received a knighthood in Germany for his work. From the article: 'Some weeks ago I received news that the embassy in Berne had unsuccessfully been trying to contact me under FSFE's old office address in Zurich. This was a bit odd and unexpected. So you can probably understand my surprise to be told by the embassy upon contacting them that on 18 December 2009 I had been awarded the Cross of Merit on ribbon (Verdienstkreuz am Bande) by the Federal Republic of Germany. As you might expect, my first reaction was one of disbelief. I was, in fact, rather shaken. You could also say shocked. Quick Wikipedia research revealed this to be part of the orders of knighthood, making this a Knight's Cross.'"

World's Smallest Superconductor Discovered 72

arcticstoat writes "One of the barriers to the development of nanoscale electronics has potentially been eliminated, as scientists have discovered the world's smallest superconductor. Made up of four pairs of molecules, and measuring just 0.87nm, the superconductor could potentially be used as a nanoscale interconnect in electronic devices, but without the heat and power dissipation problems associated with standard metal conductors."

Man Uses Drake Equation To Explain Girlfriend Woes 538

artemis67 writes "A man studying in London has taken a mathematical equation that predicts the possibility of alien life in the universe to explain why he can't find a girlfriend. Peter Backus, a native of Seattle and PhD candidate and Teaching Fellow in the Department of Economics at the University of Warwick, near London, in his paper, 'Why I don't have a girlfriend: An application of the Drake Equation to love in the UK,' used math to estimate the number of potential girlfriends in the UK. In describing the paper on the university Web site he wrote 'the results are not encouraging. The probability of finding love in the UK is only about 100 times better than the probability of finding intelligent life in our galaxy.'"

Comment Re:Cable? Why? (Score 5, Informative) 165

... the ocean might simply be good at blocking transmissions.

The ocean isn't just good at blocking transmissions. It's ridiculously good at blocking radio waves. If you work the math on this page, you can see that your basic WiFi transmission (at 2.4 GHz) will experience an attenuation of almost 1700 dB/meter! At that rate you'd get far less than a millimeter of penetration.

Even the lowest frequency short wave bands (1.8 MHz) get 46 dB/meter attenuation. It starts to get possible to receive RF when you get down in the kHz range but of course, your data rate goes to hell.

For underwater communications under a couple hundred meters or so you can use an acoustic modem. Even then, your best data rate is going to be on the order 2400 baud or less.

If you want high speed underwater communications, you gotta use a cable.


Difficult Times For SF Magazines 218

Lawrence Person writes "Another speculative fiction magazine folds: Realms of Fantasy is ceasing publication. This comes hot on the heels of the announcement that the venerable Fantasy and Science Fiction will be moving from a monthly to a bimonthly schedule, and underscores what a tough environment this is for science fiction and fantasy magazines, all of which have suffered declining circulation for quite some time. This is a real problem, since short fiction is generally where new writers cut their teeth, appearing in print alongside their more famous peers. Given that a one-year subscription costs less than the average video game, those with an interest in science fiction might want to consider buying subscriptions to Asimov's, Fantasy and Science Fiction, and Analog. (Those in the UK might want to add Interzone and/or Black Static and Postscripts as well.)"
It's funny.  Laugh.

Submission + - Thank an Engineer (ti.com)

ssimmons writes: TI has some videos up that try to imagine a world without some of the things that most people take for granted and then ask people to 'Thank an Engineer' for the world we live in. OK, so they're not really funny. Still, as an engineer, it's nice to get a little love for the work I do.

Comment Re:That isn't gps working underwater (Score 1) 99

The sub uses GPS for positioning on and near the surface. The rest of the way it's using inertial navigation.

USL@NOC is also working on multibeam sonar so that the robot can assess its position using geologic features on the bottom (up to about 200m away I expect) for position keeping in a current.

I'm not sure why they'd use a multi-beam for station keeping when they already have an ADCP (Acoustic Doppler Current Profiler) on board. The particular ADCP they're using here was made by a company I used to work for (in fact, I wrote a lot of the firmware in that sucker) and is accurate to within a few tenths of a percent and can track the bottom out to 200m.

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