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Comment Re:What the frack (Score 1) 350

Inertial Navigation Systems are good pieces of hardware, and without giving anything away I can tell you that you can assume most major warships in any of the better NATO navies will be equipped with it. However, no unit (surface or submarine) relies on it as a principal means of navigation, certainly not for months at a time. It is a system that starts out accurate and gets progressively less and less so as you go, especially in rough seas. Remember, it has to add up every bit of inertia in every direction - including wave motion. By the time you reach your destination your area of probability can be so large that celestial navigation (using modern instruments) can actually be more accurate. INS has to be periodically corrected, and when GPS isn't available or is degraded (or we are training without it), this is done by old fashioned traditional navigation methods. Fixes based on visible features (land, nav markers), celestial fixes, bottom contour fixes, etc. It's bottom contour fixes using depth sounders that submerged vessels use as their primary means of navigation.

INS does have its uses. And while I can't discuss when and what situations would call for its use as a primary means of position fixing, it probably shouldn't be too hard to work out likely scenarios. Traditional navigation is still king. INS is only used as a primary means of navigation by the authors of war novels.

Comment Re:What the frack (Score 5, Interesting) 350

I'm an officer for the Royal Canadian Navy. I've spent time on the bridge of some of our American friends' warships and it's sometimes a white-knuckle experience. Sailing into northern waters away from large constellations of GPS satellites can easily bring your dilution of precision to the point where you could be almost anywhere, and yet many of my American friends didn't even know what the reading meant on their display. HDOP would be flashing red on the bridge and they would be all fat and happy sailing at full speed. ECPINS put a dot on the electronic chart as to where they were, so that meant that's where they are.

It was with puzzlement that I first learned that Americans didn't teach celestial navigation to its officers. It's not that celestial navigation by itself is really all that necessary, because yes, even without it, there are other methods. But the training of it produces officers that have a better understanding of when their machines are lying to them. It, and all the related skills you need to learn to make it work, gives more useful things in your toolbox to draw from. Because I will tell you from experience, it is not a matter of if a GPS will give you a wrong answer. It's a matter of when.

It's also, if you ask me, not a matter of if but when a shooting war finally breaks out. And if and when it does, you can guarantee that one of the first priorities for the enemy will be to deny NATO (one way or the other) the use of GPS.

Perhaps with a renewed focus on training techniques that don't rely on toys, the USN will stop having the most collision-dented ships in NATO.

Comment No mention of Concorde (Score 5, Insightful) 238

I love how there is no mention of the Concorde, which did it faster and carried more passengers on 1970's technology.

It's like building a new space shuttle that is smaller than the shuttle was, and then comparing it to the Gemini capsules in the marketing. What, do they think the world has become globally amnesiac in the last ten years?

Comment Re:Never (Score 1) 152

I miss the days when Slashdot tags were sort of a group vote, the more people that entered a tag, the more likely it would show up. Crowdsource publicly visible tagging, But then Slashdot realized that it was used more for people to point out the flamebating, slashvertisement, and just generally fuckwitted posts than it was to actually tag the article's content. A feature that got dropped like a hot potato, and which I am very much missing right about now.

Comment Re:Ha? (Score 5, Informative) 112

DuckDuckGo doesn't have a crawler. Well, they say they do, and I'm sure they have some basic crawling, but they only say that so they don't look silly for being a search engine that doesn't actually do search. They buy their results from Bing, and then do some value added stuff like munging in Wikipedia results. I doubt Apple wants to buy something that sends money to Microsoft, and they certainly won't back Google. And Apple doesn't have the expertise to build an effective search engine on their own.

Comment Interesting wording (Score 3, Insightful) 106

I find it very interesting the wording. They think that they should have "ceased supporting the dual EC_DRBG algorithm immediately after security researchers discovered the potential for a trapdoor" and that their failure to do so was regrettable. What about their helping to develop the algo with a back door to begin with?

They are essentially coming out and admitting they are sorry that they didn't drop support, because if they had dropped support at least they would have been able to cover up the fact they intentionally create algorithms with flaws to begin with.

Comment Re:Pseudoscience Snake-Oil Hogwash (Score 1) 154

What I wrote was completely accurate. It's the reason why there is a campaign right now to train people on the ways to detect a stroke, because there is no feeling when you bleed in your brain. There is no pain, no warmth, no tingling, because there are no sensory receptors in the brain. None. Sensory receptors are nature's burglar alarms. You put sensors on your outer doors, and windows, and maybe in a few main hallways. The master bedroom door likely doesn't have a sensor, because once someone is there it's too late. There's little advantage to putting sensory receptors in the brain, so nature didn't.

Epileptic seizures are neural cascades that are still not well understood. What they are not is electrical, though they are sometimes dumbed down and explained that way because that is the way neural transmission is sometimes explained. There are electrochemical reactions that are involved in a seizure, because they are involved in all neural activity, but what a person who is experiencing the advance symptoms of a seizure is feeling is not electricity in the brain, but the beginnings of that neural cascade and its effects on different areas of the brain. There are as many different pre-symptoms of a seizure as there are people that experience them, though they are sometimes grouped into broad categories. Just like people who experience migraines have many different types of pre-auras (auditory, visual, sometimes olfactory). People who feel headaches feel pain not in the brain (did I mention there are no receptors there?), but in the scalp, neck, eyes, or muscles of the head.

If the person wearing this device we are commenting on here had electricity actually passing through his brain, what he would have felt are the stimulating effects on the part of the brain that the electricity was passing through. He would have seen lights, or heard something, or been hungry. What he wouldn't feel is tingling, because there is nothing in the brain that can feel tingling. There are no sensory receptors in the brain.

Comment Pseudoscience Snake-Oil Hogwash (Score 1) 154

From the article:

I felt "tingles" pulling and hitting my brain on the left side and in the middle.

Wrong. The author may have thought that, because the author was a moron. The author felt exactly nothing hitting his brain because the brain has no sensory nerves servicing it. Anything that anyone feels with this device is sensations in the skin or muscles of the skull.

The idea that putting patches on the skin of your head and applying a voltage ends up passing any actual current through your brain is rather ludicrous to anyone who understands anything about electricity and biology. Think of it this way... take a hard boiled egg and peel the shell off it. This is your brain. Now take the egg and put it in a glass of salt water. Then take that glass and wrap it in slightly damp leather. Now put electrodes on either side of that package. How much electricity do you think is actually passing through the egg?

Submission + - New Technology Projects Solid Feeling Objects Into the Air (bbc.com)

Excelcia writes: Researchers in Bristol are using ultrasound to create invisible objects in the air that you can touch and interact with. The new technology, called ultrahaptics, uses a phased array of ultrasound speakers to focus the sound waves in almost any way they want. It's not in any way actually solid, but it can emulate the haptic response from pressing buttons. Is this one step closer to a holodeck?

Comment I call hogwash (Score 5, Informative) 349

I call this hogwash. When you ask Windows what version it is in software, it doesn't return its marketing name (Windows 95, Windows 2000), it returns it's platform ID (1 for DOS based, 2 for NT based), and its version numbers in major, minor format. Windows 95 returned 4.0 (platform 1), Windows 98 returned 4.1 (platform 1). Windows 2000 returned 5.0 (platform 2).

Comment Servers? (Score 1) 326

Both sets of information — from the car and phone — are sent to Katasi's servers.

Well that's not even a little troubling. I mean, one stop shopping - a central location that stores data on where everyone is all the time, and who is driving where any time someone gets in a car. All because some people drive while texting? That's not overkill at all. Nuh uh.

Betcha law enforcement has a woody about this.

The NSA doesn't need to do covert data surveillance. They just need to start up companies like Google and this Katasi that can do it all right in the open.

Errrr.... wait....

Comment Don't buy off Broadcom directly then (Score 1) 165

No manufacturer wants to sell in small lots. If I called up Intel directly and said I want a hundred of anything, their salesman would laugh at me too. That's what distributors are for. They buy in volume and sell to the little people. Or other board makers that bought more than they need and want to unload some. Looking at Alibaba.com right now I can see more than one, likely in the latter category. Available in any quantity Hardkernel would likely want to buy, and at a price point that should make the boards doable at their current selling price.

I have a hard time believing that their discontinuing the board is linked in any way to Broadcom's refusal to sell to them directly. I would be more inclined to believe they didn't get the interest they thought they would, and that the RPI community's antipathy towards them has given them cold feet.

The solution of this problem is trivial and is left as an exercise for the reader.