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Comment: Re:You sunk my battleship (Score 1) 439

by QQBoss (#49058007) Attached to: Will Submarines Soon Become As Obsolete As the Battleship?

Depends on when you are talking about. Pre-2K, with the aid of an FO (Forward Observer), the shells could get fairly accurate by the 6th or 7th shell, 10th if the seas are high. Given the size of shells involved, though, that means you probably leveled an area the size of a small shopping center to hit the outhouse that had been your target.

Today, totally different story. With laser guidance from an FO, tiny little winglets will dance enough that as long as your target is within a cone of the shells target it will be hit within 1 meter. No FO? GPS guided shells will hit typically within 3 meters of whatever dot you put on your map. And if you can get optical terminating shells, they don't have the ability to just hit a window, but a particular pane of a window. Look up for yourself what Jane's has to say about cruise missile accuracy for projects like JASSM (because I don't recall what I am at liberty to disclose and too lazy to look it up from a beach in Thailand). Artillery shells can be built that have every bit of accuracy, just less distance and less cost per shell (until you include the cost of the ship, the crew, the support crew, etc...). This is done for land-based artillery guns and tank shells, as well. If you watch cable TV, I am sure you can find one of those "10 Best Whatevers" that will wrap shiny graphics and add in a few reasonably knowledgeable experts around Jane's information.

Comment: Re:Not automatic (Score 1) 60

by QQBoss (#49006289) Attached to: How a Hardware Designer Was Saved By His Own Creation

Demonlapin is correct: if you are doing proper chest compressions, there is a high likelihood you will crack the ribs of most adults over 40 (almost guaranteed if a woman over 60), and a reasonable likelihood of doing it to younger adults.

But, if you got out of the training that you should only do CPR if the AED doesn't work, you misheard the instructor. You shouldn't attempt to use an AED until after the first round of CPR has been performed (though not taught by the ARC at this point to lay rescuers, some schools of thought suggest that no initial rescue breaths are required for the first round if an AED is known to be available or professionals will be on the scene in less than 4 minutes from witnessed collapse). The AED should not be used until at least one round of chest compressions has been attempted. There are multiple reasons for this, which I won't go into. That you need to continue CPR if it can't shock the patient, or if the patient doesn't respond to the first shock, is, of course important. And that you should STOP doing CPR if the person does respond, hopefully that is a given, 'cause it does hurt when done properly!

Comment: Re:Not automatic (Score 5, Informative) 60

by QQBoss (#49004205) Attached to: How a Hardware Designer Was Saved By His Own Creation

Trained personnel? If they were capable of reading the instructions that were in the case, or listening to the directions spoken by the machine, that covers about 95% of what training is really required for a normal adult.

I am a certified First Aid/CPR/AED instructor for the American Red Cross. The level of training required to use an AED if you are calm, cool, and collected (and no cross-chest nipple piercings are involved) is less than is necessary to assemble a table from Ikea. That said, when you need to use one, calm, cool, and collected are frequently out the window, which is why training is recommended. Almost anything you can do wrong, the machine will let you know that something is wrong so you can correct it. Many kits even come with a razor to deal with the overly hirsute. Oh, and I was involved with building an internal pacemaker capable of phoning home to the doctor (though you had to hold the phone up to your chest, it couldn't reach out and grab it) back when they still required DSPs.

The AEDs automatically analyze heart rhythms (or lack thereof) and notify the operator to push a button if a shock is required. They will provide a shock for two different rhythms- V-fib (Ventricular Fibrillation) and V-Tach (Ventricular Tachychardia). They will not shock for asystole (no electrical heart signals detected at all, and must be avoided so you don't try using an AED to jump start your car or do some tiny welding) and PEA (pulseless electrical activity- the wiring is working, but the engine is dead).

Long story longer: Heart Attacks are NONE of these cases. AEDs WILL NOT PRODUCE A SHOCK for a heart attack, which is simply the blockage of blood to the heart, usually caused by a clot breaking loose. Heart attacks can result in cardiac arrest, which does result in one of the four cases above, but an AED will do nothing for a simple heart attack. TFA correctly describes that he had a cardiac arrest (sudden dropping to the ground), but incorrectly says he flat-lined (asystole, AED wouldn't have helped in that case) and that he had a heart attack (if he only had a heart attack, he could have walked off the court and hopefully gotten a quick ride to a hospital).

Any more info needed? I strongly encourage you and everyone to take a First Aid/CPR/AED class from whatever qualified source is available (Red Cross, Heart Association, etc). The chance that you will ever need to perform CPR is pretty low, but I have had to deal with a choking in a restaurant, a compound fracture at a swimming pool, a petite mal siezure on a subway, and other situations that are far more likely.

Comment: Re:Service restored? Umm, not via my ISPs (tested (Score 1) 45

by QQBoss (#48711539) Attached to: Gmail Access Starts To Come Back In China, State-Run Paper Blames Google

As an addendum to my previous comment, starting at approximately 11 pm Beijing time, three different VPNs I am using- one free, one paid, and one corporate- have all been blocked within China. Hopefully this is temporary. IT offices will have heads on the chopping block if this is still happening in 8 more hours (or less).

As of 11:45 pm, two of my three VPNs are working again. The one that isn't is, of course, the one that people will get fired for. C'est la vie, time for bed.

Comment: Service restored? Umm, not via my ISPs (tested 3) (Score 4, Informative) 45

by QQBoss (#48702729) Attached to: Gmail Access Starts To Come Back In China, State-Run Paper Blames Google

I am in Beijing. I know not of this restored service of which TFA speaks. Anything Google related website-wise (and including other services, like Google Earth) have been blocked on the PC since July or so (as opposed to just slowed down to 1 Kbyte/minute previously) but Google's client on cell phones worked without a problem. What was blocked on Friday was the phone client and any other services not covered by the previous block. As of my posting this message, everything G is still only accessible for me via VPN- Freegate or paid, either works fine. Funny thing, though, if I use Freegate, I can't use any services at slashdot (I had to shut off FG so I could post this message and see how a comment I made in another thread had been moderated).

The only thing that I use frequently that is hit and miss functionally without a VPN is Google Translate, which I am guessing is because some big Chinese web sites claiming to do translation are actually just front ends to Google translate and thus stop working.

Comment: Re:Hadrly a new story (Score 3, Interesting) 349

by QQBoss (#48696317) Attached to: United and Orbitz Sue 22-Year-Old Programmer For Compiling Public Info

Actually, it is funny, because Orbitz was started by the airlines themselves. They didn't need to scrape cheap airfares to lower prices as much as cut out the travel agents as middlemen:

Five airlines--United Airlines Inc., Delta Air Lines Inc., Continental Airlines Inc., Northwest Airlines Corp., and, later, AMR Corp. (American Airlines)--teamed to create a new online travel service. (American became an equity partner in March 2000; total start-up funding was around $100 million.) Together, the five founding partners controlled 90 percent of seats on domestic commercial flights. Existing computer reservations systems such as SABRE did not present competing fares in an unbiased way, said company officials.

What makes it even funnier to me is that American Airlines was one of the founding companies of Orbitz who was trying to lower prices from SABRE, which American Airlines started in 1960!!!

Comment: Re:Bogus algorithm (Score 1) 68

by QQBoss (#48687835) Attached to: The World of YouTube Bubble Sort Algorithm Dancing

I teach both C and Data Structures. Bubble sort is for my C class where I am trying to make sure the students fully comprehend arrays (most of my students come from a non-existent programming background, and the school isn't sold on my teaching them Python as a first language just yet as apparently I am the only instructor who can use it meaningfully), how indexes work (getting them to reverse an array or a string doesn't quite seem to do it for about half of them), and my better students will have implemented bubble sort on linked lists by the end of the semester, as well. Understanding that bubble sort works isn't a problem for them, but they are only starting to think beyond what a single loop can do algorithmically. I have tried jumping to insertion sort and as a whole there is poor integration of the knowledge to take forward. Good/better/best options just can't happen for most of these students at this point, and so it has to wait for Data Structures where the first sort they learn is Insertion Sort and I don't care which language they use. I guess if someone started using Mindfuck or Ada I might start to care. They add every sort to one big program where they can calculate how much work each sort does and how much system time it takes to operate for randomly generated lists.

As for concerning themselves with cache misses as one person suggested it, until students have a better understanding of systems, that can't be readily done with a class of 40+ frequently unmotivated students (it can with ~10 motivated students, the breakpoint occurring somewhere in the middle, of course), though I start introducing the penalties of register/cache/RAM/disk in this class so that by the time I am teaching embedded systems the students who chose that path usually have a good grasp of it, with the best ones looking even at divide instructions with disdain. With the semester system being what it is, though, teaching all of that as a simultaneous, cohesive chunk of information just isn't going to happen.

Comment: Re:Many DDR3 modules? (Score 1) 138

by QQBoss (#48666829) Attached to: Many DDR3 Modules Vulnerable To Bit Rot By a Simple Program

It can, but the chances of it staying perfectly readable is very small. And realize that removing RAM from a machine puts it under a very different condition than intentionally accessing the RAM in a pattern which causes faster than normal leakage, so the results aren't mutually exclusive.

Comment: Re:Study financed by (Score 1) 285

by QQBoss (#48650655) Attached to: Study: Red Light Cameras Don't Improve Safety

In this case, you an believe both, as the statements aren't contradictory, only your misunderstanding of what you read. The law the judge is referring to is Illinois Uniform Vehicle Code, not federal law (though it generally does follow Federal Highway Administration guidelines). But you are more than welcome to keep believing your misconceptions and misunderstandings. Every state has one, btw.

Comment: Re:Study financed by (Score 1) 285

by QQBoss (#48645033) Attached to: Study: Red Light Cameras Don't Improve Safety

The summary is shit (not shiat), though, because THERE IS NO FEDERALLY MANDATED MINIMUM TIME FOR AN AMBER SIGNAL LIGHT! Why do people think there is??? There are lots and lots of recommendations, and most states follow them, but local traffic laws aren't covered by federal law, and shouldn't be unless a traffic light gets used on an interstate.

As a general rule, what was taught to the Civvies I knew (I was comp sci, the civivies were on the floor below us) when I was in college was that amber lights should have a minimum duration of 3 seconds and go up by .5 second for every 5 MPH over 30 MPH. The Institute of Traffic Engineers currently suggests it be .5 second longer for each 5 MPH over 25 MPH. But there is no federal law or federally enforced standard. There are just municipalities who can't (or won't) comprehend physics when it works out in their financial favor.

+ - Municipal FTTH Feasibility

Submitted by honestOctave
honestOctave (3893945) writes "Local rural municipality is upset it didn't get Google's Fiber bid that went to Kansas City. They are heavily invested in a proposal that would *supposedly* bring Gigabit to each household via Fiber To The Home with smart metering. The market involves 3700 households, of which they are expect 40-60% to particpate. The price tag is $25 Million with principal and interest over 20 years. Am I the only one thinking the numbers aren't really adding up with contention ratios, backhaul costs, etc.? Current cable company offers 50-80 Mbps. DSL offers 1.5-20 Mbps. Anyone care to provide some holes in this arrangement from any experiences they might have in the industry or similar arrangements?"

Comment: Re:There's a lot more going on... (Score 1) 161

by QQBoss (#47781417) Attached to: Research Shows RISC vs. CISC Doesn't Matter

That is more or less accurate. The goals of the original RISC were stated to be making a Reduced Instruction Set Computer, but what was in fact produced was a Reduced Instruction Set Complexity CPU. By restricting the touching of memory to only loads and stores, all other instructions that were able to be executed in one clock COULD be executed in one clock always. Whereas some CISC instructions involving arrays could kick off 10+ memory touches as a side effect, RISC instructions could never do that (sans via exceptions). So when all 10 of those memory touches weren't required, the RISC architecture could optimize away the unnecessary ones (which was a bitch in 1990, but common place by 2000 and exceedingly trivial by 2010, to put it roughly).

I taught CISC architectures (68K mostly) and was a minor architect for PowerPC (I helped work on the early EABI- embedded application binary interface- architecture)

But this leads to a problem: Cache. That CISC operation that made 10 memory touches took roughly 10-18 bytes of instruction storage (68K example), and 10 data cache accesses that would either hit or miss. But a 16 bit RISC would take 22 bytes (and didn't double the number of useful registers available) and a 32 bit RISC would take 44 bytes (but generally doubled the number of useful registers, reducing the need for so many loads and stores). Thank goodness you took fewer transistors to implement the instruction pipeline, because you need them all back to make the Icache bigger! The hope being that those 10 memory touches were rarely needed if you had more registers, so you could cut back on other loads somewhere (but we didn't get really good at doing that automatically until the late '90s, by which time we could show that the RISC penalty was effectively negated, specific numbers remain the property of my name-changed employer but were down to single digit percentage differences). Dcache would have the same hits and misses, unless you were also able to allocate saved transistors to some Dcache which might affect hit rates by some low single percentage points.

But with complicated instructions come pipeline clocking challenges. Implementing the entire x86 pipeline in 5 stages would result in having a sub-200 MHz pipeline today- the P4 push to 4 GHz required up to 19 stages (and who knows how many designers) worst case, IIRC! Meanwhile, most RISC architectures zoom along happily with 5-7 stages and only manufacturing nodes or target design decisions keep them from clocking up to x86 frequencies.

Hands down, it was never any 'benefits' of CISC (or, specifically, the x86 architecture) that allowed Intel to take the field, it was market forces and manufacturing might. A win is a win.

BTW, to the AC GP, just because an instruction appears complex (most SIMD operations, MADDs, FPSQRTRES, etc...), they still count as RISC if they can be either executed in one clock or at least pipelined with nominally one result per clock if they don't impact the pipeline for all the other commonly executed instructions. After all, we can made a divide instruction execute in 1 clock, too, as long as you don't mind your add instructions taking 16x longer (though still one clock), but that is cheating.

There's no future in time travel.