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Comment Re:Correct me if I'm wrong, but... (Score 1) 53

run it for an hour on a dynamometer at highway speeds -- let's see them rig the firmware to cheat on that!

If it were me, I'd use the accelerometer and gyro in the traction control system to detect if the car is actually moving. The car isn't going to go over random bumps or turn a corner when it's strapped on a dyno.

Comment Re:The numbers have gotten worse (Score 1) 53

The average car these days is a lot heavier, due to all the safety requirements. It also produces less pollution.

In order to meet the ever increasing emissions standards, efficiency has had to take a hit.
You can increase the compression, add a turbo charger and direct injection and it's going to be very efficient. It's also going to spew out NOx compounds because that's just what happens when you burn all the fuel and there is excess oxygen left over. It combines with the nitrogen in the air due to the high temperatures.
Catalytic converters aren't 100% effective, don't work at all when they're cold and also restrict the exhaust flow.

Comment Re:Does anyone really use these numbers? (Score 1) 53

1) The amount of energy required to reach a certain speed increases as the rate of acceleration lowers, not the other way around (due to the increased time it takes, more energy is converted to heat via friction). The efficiency of the engine may drastically reduce when you make it produce more power though.
On the other hand, the faster an object accelerates, the more energy it requires to reach a given distance as it will be travelling faster, which implies more friction.

2) A car with regenerative braking can re-capture some of the extra energy used to accelerate it. These cars (are pretty much all hybrid or electric) are both heavier and more fuel efficient than those without regenerative braking.

4) What does mass have to do with anything? Burning fuel is not a nuclear reaction, no mass is converted in to energy. The mass of the exhaust from a car is equal to the mass of the fuel and air going in to it. (Ignoring any build-up of unburnt fuel or dirt inside the engine) The processes that created the oil in the first place are still happening. The water and CO2 being produced still get converted back to sugars by plants. Bacteria still break those sugars down in to simply hydrocarbons. The only problem is the rate at which these processes happen.

*) Your beef seems to be with burning fossil fuels to move a car. Electric cars don't need to burn fossil fuels. Power can be generated by other means - Hydro, wind, solar, nuclear, tides, etc.

In the case of Mitsubishi, the **number** on the sticker is related to the drivetrain of the vehicle, not the vehicle itself. an SUV with the same engine and transmission as sedan can share the same number, where as an SUV with a more efficient engine not available in a smaller car may have a worse number. Where has it been shown there is a positive correlation?

The best one I've experienced was my old Subaru Legacy. It had the same economy ratings as a non-turbo charged Impreza, despite it being maybe 300kg heavier, worse drag due to being a station wagon and two turbo chargers. It's the same engine, same gearbox and same 4wd system though. Different car, different engine management, different engine 'accessories'. This was over 15 years ago though, so no one cared. Petrol was cheap.

Comment A bug? (Score 3, Interesting) 36

Isn't this by design?
You visit a page, it checks a cookie value with the authentication server, if it's invalid you get redirected to the authentication server, with a parameter that allows you to be redirected back to where you first tried to go.
When you're redirected back, the process starts again.

This is how a lot of SSO systems work.

The 'continue' parameter needs to accept every possible entry point to every website the SSO authentication server supports.

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