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Comment: Re:Left or Right? (Score 1) 475

by johnslater (#47708599) Attached to: Google's Driverless Cars Capable of Exceeding Speed Limit

There's a lot of urban myth about this. In UK law the tolerance is actually 10% + 4kph, or 2.5mph, and it applies to the speedometer in the car, not to the true speed. This is merely a wiggle factor allowed for the speedometer in the car, which is allowed to read high up to the above formula, but never low.

So for a true speed of 70mph, the car's speedometer may legally display between 70 and 79.5. So it is not a excuse to speed, as the tolerance is only on the upside. A speedo that reads low is out of spec and illegal. Thus most cars have speedos that read a little high by design, in order to comply with this regulation. In my experience about 5% high is typical, so 73.5 indicated for true 70.

AFAIK any allowance by the cops over the true speed is entirely at their discretion. In theory you can still be ticketed for 71. IMHO this is a good thing, as it allows boy racers to surge along at an indicated 85, while still actually within what most cops would consider a safe envelope.

This policy is in everyone's interests:
- the car manufacturers like it because the wiggle factor means they can build the speedo to a lower, cheaper standard;
- the enthusiastic driver likes it because it gives an exaggerated impression of the car's performance (I was doing 100!^H^H^H^H90!);
- the authorities like it because it curbs excessive speed and thus enhances safety;
- we geeks tolerate it because we have our own independent measuring equipment.

+ - Chicago transit system fooled by federal ID cards

Submitted by johnslater
johnslater (61055) writes "The Chicago Transit Authority's new "Ventra" stored-value fare card system has another big problem. It had a difficult birth, with troubles earlier this fall when legitimate cards failed to allow passage, or sometimes double-billed the holders. Last week a server failure disabled a large portion of the system at rush hour. Now it is reported that some federal government employee ID cards allow free rides on the system. The system is being implemented by Cubic Transportation Systems for the bargain price of $454 million."

+ - Encrypted traffic being intercepted

Submitted by lucag
lucag (24231) writes "It appears that most of the encrypted traffic over the net is currently being intercepted and in some way decoded by NSA.
Here there are some references, unfortunately scant on the details that matter; actually it is not clear if it is broken algorithms, compromised protocols, MITM attacks or just plain old simple "enforced" cooperation by the providers.

http://www.theguardian.com/world/2013/sep/05/nsa-gchq-encryption-codes-security

http://www.nytimes.com/2013/09/06/us/nsa-foils-much-internet-encryption.html?smid=tw-nytimes&_r=0"
The Military

United States Begins Flying Stealth Bombers Over South Korea 567

Posted by samzenpus
from the nice-day-for-a-flight dept.
skade88 writes "The New York Times is reporting that the United States has started flying B-2 stealth bomber runs over South Korea as a show of force to North Korea. The bombers flew 6,500 miles to bomb a South Korean island with mock explosives. Earlier this month the U.S. Military ran mock B-52 bombing runs over the same South Korean island. The U.S. military says it shows that it can execute precision bombing runs at will with little notice needed. The U.S. also reaffirmed their commitment to protecting its allies in the region. The North Koreans have been making threats to turn South Korea into a sea of fire. North Korea has also made threats claiming they will nuke the United States' mainland."
Hardware Hacking

Grad Student Invents Cheap Laser Cutter 137

Posted by samzenpus
from the frugal-cutting dept.
An anonymous reader writes "Peter Jansen, a PhD student and member of the RepRap community, has constructed a working prototype of an inexpensive table-top laser cutter built out of old CD/DVD drives as an offshoot of his efforts to design an under $200 open-source Selective Laser Sintering (SLS) 3D printer. Where traditional laser cutters use powerful, fixed-focus beams, this new technique dynamically adjusts the focal point of the laser using a reciprocating motion similar to a reciprocating saw, allowing a far less powerful and inexpensive laser diode to be used. The technique is currently limited to cutting black materials to a depth of only a few millimeters, but should still be useful and enabling for Makers and other crafters. The end-goal is to create a hybrid inexpensive 3D printer that can be easily reconfigured for 2D laser cutting, providing powerful making tools to the desktop."

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