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Comment Re:I did this (Score 1) 725

my g/f was shopping for a new TV. She found the model she wanted, on sale, and was just about to tell the sales guy "I'll take it" when she was interrupted by her phone. She needs to pay attention to incoming messages because she delivers babies. She excused herself and consulted the latest news about one of her patients on her phone. The sales guy must have assumed she was price checking -- he quickly said, "Let me talk to my manager" disappeared and when he came back offered an additional $400 discount!! She got the unexpected benefit of price checking without actually doing anything.

Places that do what it takes to make the sale will outlast the places that cry "waaaah, that's not fair!"

Comment Re:Mac vs. PC (Score 1) 453

Ok, that's fine and dandy, however when using the word "America" the singular refers to the USA, the pl refers to both continents.

No, the word "America" in the singular refers to the USA only in the common usage in the USA. In most of the rest of the world, this is simply not true.

Comment Re:Mac vs. PC (Score 1) 453

So is this a pedantic semantic argument? I guess so, but I don't see how you could possibly justify that usage of America.

How many continents are there? It seems like a simple question, but it really depends on where you are from. In most English speaking countries, we are taught that there are seven continents. In most of the rest of the world, including most of Europe, S.America, and Latin America, the answer is six. What we call North and South America, most of the world refers to as simply America. How could one possibly justify that usage of America? If you grew up in Brazil you would ask the same question but with entirely different meaning.

Comment Re:Yes but... (Score 4, Insightful) 81

It's technically illegal to fly UAVs without visual contact in visual flight rules air space.

Not quite.

The FAA controls the national airspace with a white-list approach. Everything is illegal unless a specific category of safe flight has been defined. AC 91-57 defines the Model Aircraft Operating Standards and creates a specific legal exemption for vehicles flown for recreational purposes. This exemption also applies to UAVs, provided they are flown for recreational purposes. However, there is no exemption for operating a UAV for commercial purposes. Even flying an R/C aircraft is illegal if the operator attaches a camera and attempts to sell the resulting aerial imagery!

The FAA recognizes that people and companies other than modelers might be flying UAS with the mistaken understanding that they are legally operating under the authority of AC 91–57. AC 91–57 only applies to modelers, and thus specifically excludes its use by persons or companies for business purposes.
-- from FAA–2006–25714, Unmanned Aircraft Operations in the National Airspace System; Notice of Policy; Opportunity for Feedback (FAA link to pdf is down right now)

Technically, you or I could fly a 1:1 scale F-22 Raptor, but only if it were for recreational purposes.

Comment Re:paper in your wallet (Score 1) 1007

Now I have an oh-so-sort dictionary (only 160 entries!) to feed to my favorite password-cracking program. The odds of my success just went from potentially being neigh-impossible to almost-certain.

Now tell me, if you happen to find a wallet with a similar password page in it, at which website will you direct your favorite password cracking program? What username will you pair with the password?

Comment Re:No. (Score 1) 203

I'm wondering why there's a need for drones to interfly commercial airspace here in the US,

My company demoed our UAS for the FAA related to this new legislation. The problem is that under current FAA regulations, it's illegal to fly UAS's in the national airspace -- I'm not referring to a UAV flying from LA to NY, I'm referring to a UAV flying over an open field on private property several miles from any human habitation. That's still national airspace and is still regulated by the FAA.

The main purpose of this new legislation is to define terms under which UAS's can legally fly in the US -- so that we can at least develop UAS technology legally. Of course, since they are crafting new regulations, they are thinking much further down the line for when the technology may be ready to safely fly with other passenger airliners and such. But the immediate concern is to allow research and development to occur. If things don't change soon, a lot of UAV/UAS research will simply leave the US for country's where it is already legal.

Comment Re:Wolfenstein 3D? (Score 1) 117

I remember playing Stellar 7 before Starglider (doesn't mean that's the order they were released, of course).

Marathon by Bungie Software is another one that is often forgotten -- probably because it was only available for Apple Macintosh initially (1994). Frankly, it blew Doom out of the water with better storyline, graphics, and 8 person multi-player deathmatch -- appletalk network, no tcp/ip support.

Not sure if Marathon would qualify as a 'game engine' for this list, though the game engine for Marathon 2 was open sourced eventually, now called 'Aleph One'.

Comment Re:And criminals... (Score 1) 389

so the Mayor pointing out "It would be stupid to commit a crime"

If this is true, then why are government officials so reluctant to have their own activities monitored? Why do law enforcement get so edgy about being filmed? Why are cameras not allowed in most court rooms? Why aren't public officials monitored all day long? It just stops crime, after all.

Also ridiculous is that video is worthless without follow through. My bicycle was stolen FROM THE COURTHOUSE when I had to go for jury duty. Sure enough, the whole thing was caught on video. Guy walks up, cuts the locks and wanders off with five bikes (one at a time). The cops watch the video a few times, "Yup, this guy stole your bike. Nothing we can do, really". I fill out a form, and precisely nothing else happens. Hooray for security cameras.

Comment Re:TCP? (Score 1) 536

I just finished updating the checksum routines at my company. Amazingly, they had been using an 8-bit XOR checksum for years (!) on a mission-critical wireless data link. Since this was low-level mission-critical code with lots of proven flight-time, I had to prove conclusively that the new method would, in fact, be better.

TCP uses a 16-bit checksum, so you have 1 in 65536 chance of an error packet being incorrectly validated as being correct. To make matters worse, it uses 1's complement instead of 2's complement, so 0x00 and 0xFF are indistinguishable.

It's not as simple as saying 1 in 2^N chance of error for an N-bit checksum. It depends strongly on the specific checksum algorithm, and to a degree the number of bits, length of data packet, and expected bit error rate.

For example, 8-bit XOR lets 12% of 2-bit errors through undetected, and 16-bit XOR only brings that down to 6%. WAY different than if you expected it to change from 1:256 to 1:65536. But an 8-bit CRC checksum has 1:10^8, and the 16-bit version has 1:10^16 chance of undetected error. Again, WAY different than 1 in 2^N chance.

Surprisingly (to me at least), 1's compliment catches *more* errors than does 2's compliment. (the reason being that a pair of bit inversions involving the MSB remains undetected by 2's complement, but is caught by 1's compliment)

We decided to go with a 32-bit one's compliment Fletcher checksum -- good compromise between performance and error checking for our application.

Comment Re:My call... (Score 5, Interesting) 358

They called my lab repeatedly while I was a grad student, after several calls I kept a log with time, date, and apparent Caller ID number (which was always bogus) and any info I could get out of the operators. But hey, I was a grad student, so I had time to kill, I just kept them on the phone for as long as possible.

scammer: Your car warranty is expired, would you like to renew your auto warranty?
me: expired?
scammer: yes, wou---
me: are you sure my warranty expired?
scammer: yes, would you like to renew your auto warranty?
me: well, which car are we talking about?
scammer: The newer one
me: the new one? i bought them at the same time.....
....
and when I got bored (rare) or sensed that they were about to hang up (usual)
me: I'd like you to know that I report every one of these calls to the FTC (and I really did: http://www.ftc.gov/phonefraud )

I think my number finally got blacklisted by their phone operators or something, after awhile they just hung up on me every time. Once the operator just tried to heckle my school's sports team. (its tough to rattle a geek by making fun of a football team) I *always* pressed '1' when I got those calls, must have logged at least 30 calls on the FTC website.

Comment Re:Problem? Naaaaaah (Score 2, Insightful) 169

Hello, yes, emergency-- What? You are the 9-1-1 dispatch center where? Tulsa?"

Or just dial 404-658-6666, which is the direct line to City of Atlanta 911. (Useful to know when your cell phone happens to connect to a tower outside the city limits, and 911 routes your call to the county emergency services, but the county won't send anyone to your address, because you live inside the city limits, and your call is disconnected when the county operators attempt to transfer you to the correct call center ..... four times in a row ..... )

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