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Comment: Re:Big Data (Score 1) 439

by srmalloy (#49063053) Attached to: Will Submarines Soon Become As Obsolete As the Battleship?

Take for instance the Harpoon, it's comparatively slow compared to the Russian stuff. But it is designed to be fired in huge numbers to overwhelm air defence systems.

Actually, all antiship missiles are designed to be fired in large numbers to overwhelm air-defense systems; that's one of the things that the US Navy's VLS systems were designed to counter. Defenses against antiship missiles are limited by their cycle times and total load -- how fast they can attack a new target and how many shots they carry. Swing-arm launchers that have to load a new missile each time they fire (or fire twice, depending on the launcher) have a slower cycle time, and may not be able to use their entire combat load in the time from detection to target (this is one of the things that drove Soviet supersonic antiship missile design, to reduce the engagement window); with a VLS system the reload cycle time is eliminated, allowing a guard ship to fire as fast as it needs to. This changes the parameters of engagement to a question of how many missiles can be carried, and produced the proposals for fleet-defense ships that were essentially nothing but massive VLS arrays, carrying several hundred launch cells each and relying on the task force's Aegis vessels to provide guidance.

While a battleship with a CIWS which has unlimited shots and can track super fast targets kind of cripples airpower and missiles (or is advertised to do so).

I can't speak for other CIWS systems, but the Phalanx system definitely does not have unlimited shots; the weapon has an internal load of ammunition (roughly 30 seconds of firing at low cyclic rate), and once the combat load is shot, the CIWS needs to be reloaded. Block 0 Phalanx would require 10 to 30 minutes to be reloaded; the Block I and later Phalanx systems can be reloaded in under five minutes. Five minutes for a Mach 2 antiship missile is 100 miles; once the incoming missile comes over the horizon, you don't have time to reload your CIWS.

Comment: Re:Higher temperature?!?!?! (Score 2) 42

by srmalloy (#49053191) Attached to: Scientists In China Predict Pentagonal Graphene

730C for this pentagonal graphene seems much lower, which also suggests a much lower stability.

You can see that from the molecular diagram. Look at the way carbon-carbon bonds form in molecules, and what this does to the geometry of the molecule. By themselves, the bonds would 'spread out' until evenly separated in angle. In the pentagonal arrangement, the angles between bonds are not distributed evenly, which means that there is more energy stored in the bond than there is for the normal 'spread' of carbon-carbon bonds, lowering the energy that would be required to break the bonds. This is reflected in a lower temperature limit before degradation occurs. Depending on what the normal operating environment is, there may well be no noticeable difference in stability.

Comment: Re:So to cicumvent the screen locker... (Score 1) 375

by srmalloy (#48926723) Attached to: Why Screen Lockers On X11 Cannot Be Secure

... there has to be a trojan on the system or at least something connected to the X server over the network.

Not always; sometimes it's just bad design. At a previous job many years ago, I recall being able to demonstrate getting past the screen lock on Perq computers by taking advantage of processing lag -- when you hit the key combination that would bring up the password input to unlock the screen, it would briefly clear the screen lock and show the desktop -- with full access to the computer until the screen lock process updated and showed the password prompt, which blanked the rest of the screen. Doing this repeatedly, you would first open a new shell window, then run a ps -ef command to show the active processes, look up the process for the screen lock, and then do a kill -9 on the screen lock process, which got you back to the desktop. We wrote this up and sent it to Perq, and they went back and altered the screen lock code so that it didn't display the desktop when you hit the unlock key combination.

Comment: Re:Keypunch machine (Score 1) 790

by srmalloy (#48785135) Attached to: Ask Slashdot: Sounds We Don't Hear Any More?

Not just the chunk-chunk-chunk of the keypunch machine, but the rapid-fire chunkchunkchunkchunkchunk when you pulled a prank on someone and made a program card for one of the IBM 029 keypunches that declared every column a duplicate column and stuck it on the program card cylinder. Most people didn't look at the window you could see the cylinder behind, so if they started punching cards, when the first one left the punch station and hit the read station, with a second card feeding to the read station, it would automatically punch the new card as a duplicate of the first one in about a second and a half -- and then repeat the process over and over again until they figured out to turn the 'use program' switch off.

Comment: Re:Related - the clack of wheels on the tracks (Score 4, Insightful) 790

by srmalloy (#48785059) Attached to: Ask Slashdot: Sounds We Don't Hear Any More?

Most lines are welded now, so it doesn't happen any more.

Not the same way, or as often, but you still get the clack as you go over a rail joint; they're just expansion joints and less common. I recall a problem that I ran across in high school, that posited a one-mile continuous length of railroad track, and asked 'if the track expands by one inch, and buckles rigidly, so that it bends only at the middle, and is otherwise straight, how far off the ground is the rail at its midpoint?' The answer is, surprisingly, almost 15 feet (do the math: Pythagorean theorem, hypotenuse 1/2 mile + 1/2 inch, one side 1/2 mile, solve for third side). And you'll still get the rail clacking going over points and frogs in areas where you have switches.

Comment: Re:My mother is an optometrist (Score 2) 464

by srmalloy (#48722175) Attached to: Ask Slashdot: Are Progressive Glasses a Mistake For Computer Users?

One problem for computer users is that -- especially for desktop uses, we often are reading at mid distances -- neither far focus nor book distances.

The other primary problem is that both bifocals and progressive lenses have the near-focus section of the lens at the bottom, where for most computer work you are looking at your screen through the middle and upper parts of the lens. This makes both bifocals and progressive lenses pretty much useless for computer work.

What I did was to visit a supermarket and use the display of reading glasses to determine what amount of additional correction gave me clear view at normal monitor distances, then order some clip-on reading glasses with that correction. The clip-ons are about $12 -- much less than another full pair of glasses with a different distance correction -- and just as easy to keep around. I look like more of a geek while wearing them, but they're less trouble than keeping track of which glasses I'm wearing.

Comment: Re:Rubbish (Score 1) 250

by srmalloy (#48693937) Attached to: How Amazon's Ebook Subscriptions Are Changing the Writing Industry

"Absolutely and unambiguously make writing and publishing a zero-sum game"
Um, no - the more readers, the more money. It's not zero sum at all from the writers' point of view.

Actually, it always was a zero-sum game within any given pool of readers. Each individual has some amount of money that they are willing to spend buying books, and if they buy one author's books, it reduces the available funds that can be used to buy another author's books. The subscription model that Amazon is adopting changes the model by paying authors , not when their work is purchased, but when it is read. This changes the way a book is valued by its author; previously, once the book was sold, the author has no direct interest in how many times the purchaser reads it. Under Amazon's model, readers no longer own their books; they effectively rent them anew each time they want to read them. And a book that would have been purchased, read once, and binned to go to a second-hand bookstore has less value to an author than a book that would have been re-read again and again over time. And there are two ways for authors to respond to this change -- they can produce works that are worth reading again and again, or they can produce more books for Amazon to 'charge' for. As Scalzi points out, we are seeing authors, resigned to the lack of quality and rereadability of their work, breaking books up into chunks so that each piece of the book can be counted as a separate publication for the purposes of receiving payments. It will work to the detriment of the 'story collection' books -- why should an author publish an e-book that collects a dozen of their stories, when they can get a dozen times the 'read count' by publishing each story individually? Other authors might break up books into chapters as individual publications to artificially boost their 'read count', or write shorter stories instead of novels. By treating all works as equal, regardless of size, the payment method encourages authors "gaming" the system to artificially inflate the number of times their works have been read.

Comment: Re:Huh (Score 1) 279

by srmalloy (#48681893) Attached to: Newest Stealth Fighter's Ground Attack Sensors 10 Years Behind Older Jets'

Basically the USAF brass doesn't want to do air-ground missions...

As an illustration of this attitude, there was a slogan during the development of the F-15 Eagle -- "Not a pound for air-to-ground". And look at all of the upgrades and rework to make the Strike Eagle when it turned out that the Air Force didn't have the planes to conduct the CAS operations they had to do (because they continue to hoard non-Navy fixed-wing air assets to themselves, rather than letting the Army operate their own fixed-wing CAS units, even though the USAF doesn't want the CAS role), so they had to turn the F-15 into a mud mover.

Comment: Re:wow (Score 1) 571

by srmalloy (#48151263) Attached to: Lockheed Claims Breakthrough On Fusion Energy Project

And just think -- with the waste products from a fusion reactor, we can alleviate the increasing scarcity of helium.

However, we'll have to start dealing with all the environmentalists pitching a fit about people inhaling reactor waste products, or filling balloons with them and letting them float off across the countryside.

Suburbia is where the developer bulldozes out the trees, then names the streets after them. -- Bill Vaughn

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