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A Look at Smart Gun Technology

Big Smirk Re:No thank you (765 comments)

Make the police get them first!

about 7 months ago
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A Look at Smart Gun Technology

Big Smirk Let the police try it first (765 comments)

Simple, make a law that all firearms involved in domestic policing (FBI, local police, various SWAT teams) must have the smart gun technology.

What's good for the goose...

about 7 months ago
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Bugatti 100P Rebuilt: The Plane That Could've Turned the Battle of Britain

Big Smirk Range, armament, altitude (353 comments)

Planes had to have a significant range - even drop fuel tanks had to be planned for (complicated plumbing + extra drag/weight at takeoff).
Need to carry significant armament - like a few 30ish calibre machine guns (7.62 mm). By the end of the war the US was pretty much .50 caliber only - and 6 to 8 of those in a plane - that is a lot of weight. The ME262 had 4 20 mm guns/cannons. Are you going to shoot through the props? if not, then you needed wing mounted guns. If so, you needed mechanism to keep from shooting the prop off the plane OR an engine/gearbox that allowed shooting through the tip of the propeller.
Finally, naturally aspirated engines might make for a good low level racer, but at 30,000ft, you need turbo or supercharging to keep things alive. More weight, more cooling

about 10 months ago
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Bugatti 100P Rebuilt: The Plane That Could've Turned the Battle of Britain

Big Smirk Fuel (353 comments)

Its actually lack of fuel. Since the US Air force is no longer flying high compression/ high powered piston engine planes, the availability of proper fuel is extremely limited. Leaded fuel plus toluene (I think).

about 10 months ago
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Is the Porsche Carrera GT Too Dangerous?

Big Smirk Re:When you have a bad driver ... (961 comments)

So drop State Farm.

20 years ago, Mustang 5.0 (1990 model) Erie insurance was 1/2 for a plain 5.0 vs. a GT. The GT had the extra spoilers (OK, higher repair cost), but more imporantly, the actuaries figured out that GTs were more likely to be involved in an at-fault accident. I let you ponder why (crazier drivers like spoilers?).
Anyway, for a $13000 car, State Farm wanted $4000/yr and Erie wanted $1100. Keeping in mind that at the time a 200hp 5.0 was considered a wild performance car.

1 year,16 days
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Is the Porsche Carrera GT Too Dangerous?

Big Smirk Re:When you have a bad driver ... (961 comments)

Stability control often interferes with certain maneuvers - especially those that go beyond a tires ability to grip. In particular sliding or spinning the wheels. Stability control has gotten better as algorithms improve, but generally speaking, a professional driver can get a car around a track faster with stability control turned off.

1 year,16 days
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Google: Our Robot Cars Are Better Drivers Than You

Big Smirk At what speed? (722 comments)

Autonomous cars will more than likely drive at exactly the speed limit. So on that stretch of highway you were used to doing 65mph in a 55 zone... well that slow car (hopefully in the right lane) will be the Google one.

I guess that's when the human takes over?

about a year ago
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Ask Slashdot: Advice For Summer Before Ph.D. Program?

Big Smirk Out of the lab? (228 comments)

You mean there is something outside the lab?

about 2 years ago
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Driver Trapped In Speeding Car At 125 Mph

Big Smirk Re:Yikes (1176 comments)

If you have a real stick shift transmission, not only is the stick actually connected to something (the transmission) but you would also have a clutch. Now clutch releases can and do fail, and at full throttle you would not be able to get the stick out of gear (unless you hit the rev limiter). Under load (like during acceleration) many/most manual transmission cannot be taken out of gear without taking the load off. I have driving a semi-clutch less transmission that allowed me to engage gears without using a clutch - but it needed a spark interrupter to get out of whatever gear it was in.

about 2 years ago
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Driver Trapped In Speeding Car At 125 Mph

Big Smirk Re:Some observations (1176 comments)

The prius did have an issue with anti-lock brakes. Essentially you hit the brake after going over rough pavement and the brakes would start pulsating (and not stop the car). This was due in part to software they used to transition from regenerative braking to normal hydraulic braking. It lengthened stopping distances, but didn't prevent the car from stopping.

As for Toyota, as far as I know, not a single crash had been attributed to Toyota. Maybe carmats.

about 2 years ago
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Driver Trapped In Speeding Car At 125 Mph

Big Smirk Re:Some observations (1176 comments)

3) A driver is not strong enough to stop the car against the engine, especially since the engine can down-shift to get more power. Some "mythbusters"-style experimenters disagree with this statement, but their conclusions don't track with these incidents. .

Which is because a vast majority of these 'incidents' are utter BS.

Driver claims total brake failure yet later when examined by technicians, the brake seem to be working fine. Since brakes are an independant system - typically dual/redundant systems - how exactly do they magically completely fail then magically return to normal functions.

More likely the unintended acceleration is from hitting the wrong pedal (or in this case control) or simply coming up with a lie to justify getting caught speeding.

about 2 years ago
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Best Language For Experimental GUI Demo Projects?

Big Smirk Re:When I think of a quick GUI project, C#. (278 comments)

One big negative on C#. Your code ends up looking like Visual Basic.
You end up with single files with massive amounts of code. I've seen C# files with thousands of lines of code. Each button, each rule for the button etc. and they are not grouped by any rhyme or reason. The are simply tacked on the bottom as the next function. Thankfully Visual studio helps you find everything.

Makes code walk throughs either hit or miss (did we go through all the functions on that button?) or scatter brained (function 1 - start button, function 2 - dialog box, funtion 3 - menu item).

more than 2 years ago
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Scientists Print Cheap RFID Tags On Paper

Big Smirk Re:Dynamic RFID Ink? (67 comments)

Long range RFID is pretty much 900Mhz (ish). To get the chip to work at ultra low power levels it has to be pretty small. We are not talking Intel top of the line foundry but 90nm or better. Bottom line, no way to print that chip.

As for the antenna - you can print that but the variations in printing (like 1/64 of an inch makes attaching chips more expensive. The attach costs they are targeting is .25 of a cent per antenna. To achieve these numbers speed is king.

Also, for maximum performance (best antenna tuning) ink technologies don't work so well. I believe most are chemically etched now.

So you can expect the cheapest RFID tags to be around 10 c. Bigger ones cost more (but can be read farther away).

more than 2 years ago
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Shmoocon Demo Shows Easy, Wireless Credit Card Fraud

Big Smirk Re:Glossing over one problem... (273 comments)

Both, wrong... you less so.

The credit cards use an induction form of RFID. The wavelengths in question are very long - would require a big antenna to transmitt and an equally big antenna on the card to receive.... well the cards aren't big enough. So you see this spiral pattern (inductive loop) that is the antenna.
YAGI won't do it. You need something more along the lines of the magnetic sensors as you leave a store (EAS - Electronic Article surveillance).

Credit cards are 13.56 MHz RFID. That's a wavelength of ~75ft. Not going to hide that YAGI very well....

Nope, inductive loops. That's why it only works over about a meter because the strengths of the magnetic fields.

more than 2 years ago
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Shmoocon Demo Shows Easy, Wireless Credit Card Fraud

Big Smirk Re:Glossing over one problem... (273 comments)

A big magnetic field... or a choke point, like a door to the conference center.

more than 2 years ago
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Shmoocon Demo Shows Easy, Wireless Credit Card Fraud

Big Smirk Re:Mitigating factors (273 comments)

The RFID technology used in credit cards is more based on magnetic fields than electric fields. As such, stacking the cards doesn't help. The magnetic ones were somehow assumed to be more secure because they can only be read from a few inches away. Then again, store security systems use magnetic fields as well and they can read at least 4 ft away.

A Faraday cage is one defense.

Or, burn out the chip and just use the magnetic stripe (best defense). I have yet to use one of these no-contact credit card readers and have never even found a need for it. Technology that makes me less safe.... correction, makes my credit card company more expensive/less safe.

more than 2 years ago
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What a Black Box Data Dump Looks Like

Big Smirk Re:Unpossible (643 comments)

If you look at the data and read the report you will note that 40G is the maximum that can be recorded by the black box. More importantly it was only instantanious reading. Most likely a vibration, not a sustained 40G. Peak deceleration, according to the data, was more on the order of 16G, and even then, only for a few milliseconds.

Air force pilots have sustained 9+ G's during manuevers and stunt pilots + or - 9Gs.

According to:
http://en.wikipedia.org/wiki/G-force
100Gs, in short duration, is survivable in car accidents.

more than 2 years ago
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What a Black Box Data Dump Looks Like

Big Smirk Maybe not so fast afterall (643 comments)

Its unclear when the black box stopped recording. But it had a peak of -16G (smoothed average) and it increase almost linearly for 70ms.
So 1G = 32 ft/sec^2. So its a triangle with the area (1/2bh): .070 * 32 * 16 /2 and you have a total velocity change of 17.92 ft/sec or 12 mph.

I see nothing on this plot that would indicate that the car was traveling at any higher speed. Did I miss it?

Note at the beginning of the document it says something like 24mph - which is probably a better estimate than me assuming its a triangle and it take into account all the data, not just the uptick at the end.

Still, no where near 105mph.

more than 2 years ago
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What a Black Box Data Dump Looks Like

Big Smirk Re:Engineering (643 comments)

Not sure what you define as average. The average Toyota? sure 80mph it will probably rattle the wheels off. The car in question is a Crown Vic which was bought via the police department (police service package?). It would probably have been equipped with high performance black wall tires and almoust undoubtably a V-8 (I think about 300hp). Further more, the car was probably maintained by the same mechanics that maintain the police car fleet. In my opinion, most Fords have numb steering which only gets worse with age, but in this case, I would assume it was maintianed in good condition. Bottom line, 80mph on a highway is not a big deal (depends of course on the highway and conditions). The big German car makers (Audi, Mercedes, BMW) often argue against speed limits on the Autobahn because it would water down the need for performance sedans. These cars are often limited by their computer to 155 or 165mph.

Elwood: "It's got a cop motor, a 440 cubic inch plant, it's got cop tires, cop suspensions, cop shocks." (err., OK 4.6liter motor)

more than 2 years ago
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What a Black Box Data Dump Looks Like

Big Smirk Re:Engineering (643 comments)

Depends where the computer got its data.
If the data came from the same speed sensor the car's speedometer uses (a sensor on the transmission), then the moment the car left the road the rear wheels would be spinning on grass or whatever else he was traveling over.

If the black box used the input from the ABS system, that should be based on 3 or 4 sensor that measure actual wheel speed.

Typically the black boxes record the last 5 or 10 seconds before an air-bag deployment event. 5 seconds would be a long time at 75mph (~100 ft per second). So you should be able to trend the data and correspond that with the maximum acceleration of the car.

I suspect a 300hp Crown Vic would take quite some time to go from 75mph to 105... like 10 seconds. I base this on the belief that the car's 0-100 times are on the order of 17 seconds (and I suspect never reaching 100mph in those 17 seconds).

more than 2 years ago

Submissions

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Monster Cable at it again... Monster Golf

Big Smirk Big Smirk writes  |  about 6 years ago

Big Smirk (692056) writes "O.K., not "patents" but "trade marks". The hucksters at Monster Cable are at it again, this time going after a mini golf franchise. Monster Mini Golf is the target. But not to worry. Monster Cable has offered to license the name "Monster Golf" (which Monster Golf has the trademark for) back to Monster Golf for a small fee. What nice guys! I'm sure I have Monster Cable somewhere in my house. I will immediately throw it out and buy Blue Jean equivalent . I wonder if sending a letter to Best Buy and Circuit City would help?"
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