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UPS Using Software To Eliminate Left Turns
cybermage writes "The NY Times has a story about UPS using software to dramatically reduce the number of left turns their drivers take. With a fleet of vehicles their size, the time and money saved by pre-planning routes that try to eliminate left turns means big savings." Some CS major probably figured this out instead of traveling salesman.
There's a difference between concept and implementation. Traffic shaping on highway onramps can help reduce congestion on the highways itself. This must be inplemented with some sort of feedback loop between traffic flow on the highway and the number of cars allowed onto it.
If you are waiting a long time when no traffic is on the highway then the implementation is flawed.
To Terminate, or not to Terminate, that's the question - SCSIROB
It's so you don't have 80 cars coming from the same ramp trying to merge onto the freeway at the same time. When you have that many cars merging at once, they are invariably going at a very slow speed because some jackass who is afraid of the freeway is slowing everyone down, and you end up with a mad scramble as people in the right lane try to get out of the way, and people in the next lane have to move out of their way, and so on. The result is a situation where you are either going to get a collision or the whole works are going to slow down dramatically.
In Denver, they have these lights too, but they only operate during heavy traffic times. I've found them a lot easier to deal with than mass merging, and the wait between greens is never more than a couple of seconds. I can't understand why the wait between greens would be set any longer than that, since the purpose of these should only be to spread out the traffic trying to merge onto the freeway.
While the implementation may well be flawed, it's also possible that the observer's perception of the situation is too limited to adequately judge it. By the nature of the problem, shaping traffic patterns can involve local actions that look non-optimal but have a positive effect on the overall system.
Racing to a red light is definitely dumb, but doing 50MPH on a highway not only "annoys" other people, it contibutes towards more congestion and hence more total fuel usage. When you go slow, many drivers behind you will have to slow down if they are unable to pass you smoothly, in turn someone behind them will have to slow down as well, and suddenly you have a wave of slowness propagating back, ending in a traffic jam. So you might just be wasting a lot of other people's gas.
And meanwhile, in Europe, people sometimes still wonder how US-ians can consider $3/gallon "expensive" - and that is true in countries with much lower average income.
It bothers me anytime people assume their experiences are the definitive norm.
I'm from the Midwest, I've driven from Washington DC to Seattle, and I've never seen a flashing green light in my life, or if I did I didn't given it enough thought to warrant trying to figure out what it meant and just drove through it. I'm glad someone posted the Wikipedia article about it too, or I never would have known that it can mean any number of things depending on where you are.
You're going for fuel efficiency, many others or not.
I'll be the first to tell you that most people who gun it between intersection and weave through traffic trying to go faster are just flailing their arms and panicking. They're not helping anyone, especially not themselves.
However, if you're like me, and you travel the same routes day in and day out you start to see where problems occur. Well calculated lane changes to avoid things like probable stopped buses a block down and left turners without separate lanes can safe you very noticeable amount of time. Suddenly, racing past someone even if it means getting caught at the same light with them means that they're behind you when it all merges down to one lane. Instead of being stuck behind someone going 50mph on the highway, or more than likely 30mph, you're in a position to be in front of the person instead of behind them. Did it save gas? Don't know, don't care. Did it mean I could leave for work ten minutes later and not have to frustrated by slow person in front of me? Yep, and that's what I was looking for.
I hate hypermilers. Your penny pinching tactics contribute to traffic congestion and road rage. Coasting to red lights only benefits YOU if you're in front. If there's a line of cars behind you, the accordion effect kicks in and everyone goes into stop-n-go mode.
Just turn in your drivers license and get a bus pass.
How do you know he bought it up and not her? Or some other situation? Also, why should it be only she, as an asian person, that gets offended? Maybe the guy lives in China for all we know and is the minority there? Maybe he should get uptight and offended.
Whatever the case, stop this PC bullshit. It's funny. My best friend is Polish and he always comes up with the best Pollack jokes.