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Comment: Re:The source of troubles is usually in humans (Score 1) 386 386

And when C was developed, it was a HIGH-LEVEL language. It was the python or the scala of its day. It was designed as a labor-saving device, a way to write operating systems without fucking around with assembly. "Writing an operating system in a high-level language? You're fucking nuts!" And just like a proper high-level language, it held the programmer's hands and put major restrictions on what he was allowed to do, at least relative to assembly.

I miss Dennis, but I think he would tell you that while you are on the right path, you are wrong in the end. To be a real high level language would have meant surrendering direct-to-the-metal access, and he never considered that as even a possibility. His intention was to create an all-level language for the PDP/11 to improve on B (which was missing byte addressability), and even portability wasn't considered until after he achieved that goal; hand-holding was more to avoid breaking the compiler than to avoid breaking user code. He believed that if you wanted to access array[-16], you should be allowed to do that, even if it cost you your own foot (intentionally or unintentionally). His desire was to make a language that could easily map constructs to the existing hardware's assembly/machine code, which is pretty much the inverse of what high-level languages are today (or were, even then).

C was what Dennis wanted it to be. RIP, dmr.

Comment: Re: Nice Slashvertisement (Score 1) 57 57

There is some confusion in the article about Po-motion - Lumo is a different application, built in Unity and designed to run on a small processor. We used what we learned developing Po-motion (which is built in AIR) but it is a completely different platform. We'll be providing a styleguide and SDK for Unity developers, and we're planning to support them as they come up with new ideas for the system. The main challenge was making a turnkey unit that parents could afford. I'm excited to see what other people come up with for it. :)

Yes, that is my fault. I read the Po-motion page first and came to the wrong conclusion that your Lumo system was based on Po-motion. I realized my mistake after hitting send, of course. But, as I understand it, you have reduced the hardware of Mandala, an Amiga, a projector, and a camera down to one thing to plug into the wall that provides all of those features and probably a similar level of performance to what was available in 1988 (depending on CPU choice, ARM has come a long way since the 68030 was released). I would love it if one of the Mandala creators were around to pipe up (last I left them they were following the Grateful Dead around the world and living out of Hare Krishna temple/hostels). IIRC, they were also from Canada, though I don't remember which city.

BTW, you should probably update your Lumo page to indicate that you are using an ARM CPU, or perhaps "an Android-compatible CPU", rather than an "Android CPU". As for cost, running Android on an Intel NUC would certainly increase your cost, but could also increase your performance by enough to allow orders of magnitude more challenging applications, maybe for the Hammacher Schlemmer version :P.

Comment: Re: Nice Slashvertisement (Score 2) 57 57

The statement that the projector "plays" motion reactive games seems misleading, but for a typical consumer audience I can understand the simplification.

Meg, out of curiousity, other than not needing a stand-alone computer and video input, how does your product differ from Mandala, which was introduced by Very Vivid back in 1988, for the Amiga? It could use any video source (usually a projector aimed at a wall, but most any video output device would suffice) along with a video input from a camera to allow interacting with on screen content, and was quite popular with museums and other entities for setting up interactive displays in the early '90s, prior to Commodore's demise. Do you have anyone working on your team that has ever dealt with a Mandala, or even old enough to remember one?

At a hardware engineering level, has more been done than reducing part count, in effect? The Mandala was purely 2D, for example, having only the ability to determine motion on an X/Y basis parallel to the video display. Have you added another axis since you are supporting the 360 Kinect, perhaps, or could you consider that for your next generation? Additionally, would the use of 1080p or higher resolution video cameras make supporting resolutions higher than 1024x768 feasible in the future, or give more precise movement tracking? What is the granularity of movement tracking currently?

On a software level, how easy is it describe interactive objects and the interactions that can be performed along with the results? What would it take for Minecraft, for example, to be ported so that no controller was needed, just a lot of movement (my nephew REALLY needs some exercise!)? Or is it only really suited for new applications built from the ground up using your Po-Motion tools?

Comment: Re:True on water as well (Score 1) 60 60

On a ship, the captain and the pilot are two different roles and never the same person. It is the captain who has ultimate authority, the pilot is a person brought in on a case by case basis to help the captain navigate through local waters. Captains might travel the world, pilots stick to a particular stretch of water and have the local knowledge to advise the captain, usually as a requirement of maintaining insurance in case of accident. My grandfather was a ship's captain away from home almost 9 months a year, my uncle was a pilot on the Panama Canal and slept at home almost every night.

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

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 60

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 60

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 45

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 45

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) 349 349

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 68

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.

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