London Tube Lines
This is the "Northern Line" of the London tube:
It should be clear that whoever designed the tube system in London had a pretty hazy notion of the geometric concept of "line".
Was any other car company gaming emission standards?
As most of you already know, Volkswagen was recently caught cheating on emission tests. But were they really alone in doing so? The EPA data shows some suspicious patterns.
Without getting too technical (in any case, the specifics are still unclear), there's a tradeoff between fuel efficiency, and NOx emissions. So for a given level of performance, the software that controls a modern diesel engine can be tuned so that it is more fuel efficient, but produces more NOx, or it can be tuned so that it is less fuel efficient, but produces less NOx.
Since Volkswagen had problems meeting the NOx standards in the US, they decided to introduce software that detected when an emission test was being performed, and tuned the engine so as to decrease NOx production, in the process potentially worsening fuel economy relative to regular driving conditions.
One possible outcome of this procedure is that the cars involved might actually have better fuel economy in real life conditions, than during …
Without getting too technical (in any case, the specifics are still unclear), there's a tradeoff between fuel efficiency, and NOx emissions. So for a given level of performance, the software that controls a modern diesel engine can be tuned so that it is more fuel efficient, but produces more NOx, or it can be tuned so that it is less fuel efficient, but produces less NOx.
Since Volkswagen had problems meeting the NOx standards in the US, they decided to introduce software that detected when an emission test was being performed, and tuned the engine so as to decrease NOx production, in the process potentially worsening fuel economy relative to regular driving conditions.
One possible outcome of this procedure is that the cars involved might actually have better fuel economy in real life conditions, than during …
Great to see that you are back to blogging! Keep it up.
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