on the coders. I apologize. I've just had serious issues with traffic control in the past, and have encountered significant resistance. However, this does not come from the coders themselves. I do not apologize to the unimaginative buffoons though. If you've ever dealt with the people in charge of state offices, then you probably know what I'm talking about.
I understand the appeal of classical controls. I mean, everything is exact, and there is no uncertainty. You have all of your models and you can design a controller that has a rise time of x, settling time of y, overshoot of z, etc. It's very precise, and appeals to the extremely logical, mathematical nature of most engineers.
However, how accurate is that model? The model is linear, but is it a linear system? No, you have to linearize it. That linearization is only good over a certain range, and after that it fails. A linear model says I can pump 100 A through a 1 ohm resistor, but I know better.
There's also the issue of noise, but the main problem with traffic control is the model. People are highly nonlinear, and their behavior is not easily modeled. Deriving a transfer function for the driving habits of city full of people is an impossible task. The best you can do is come up with probabilities and go from there. Now, I don't know about you, but I find the math involved ugly and cumbersome.
So why not derive a set of fuzzy rules? A simple case is classifying traffic as light, medium, or heavy, which would correspond to short, medium, and long green phases. The math of membership functions is extremely straightforward. Of course, this is an extremely simple example, but intersection control is still fairly intuitive. Anyone sitting at a red light at 3 am can see that nobody's coming, so there's no reason they shouldn't have a green light. With fuzzy logic, you use the same kind of reasoning, and come up with a much more efficient traffic controller. There are some instances where an imprecise approach can lead to much better result, and this is one of them.
Who the hell needs that? Fuzzy logic can do the job better, and it's far from complicated. You wouldn't have to try and model the intersection as a plant and try to use traditional control methodologies such as cost functions. You simply have to set up some fuzzy rules and you're set. The hardest part is generalizing it to different sensor input and intersection configurations.
The problem is that we have a lot of one-track minded code monkeys writing intersection control software, and a bunch of unimaginative buffoons in charge of the state traffic engineering offices. Believe me, I know from experience.
When you spend more than you take in, and rack up more than 7 times more debt than you have assets, and are still operating at a loss, that's a bad thing.
Check out David Walker's address to the National Press Club when it is available. I'm pretty sure he's had a few more economics classes than you have, and apparently a buttload more experience. But I'm sure you'll say that the Comptroller General of the United States know about economics, right?
I keep seeing all these fantastic speeds for ATA and SCSI, but I'm completely confused. Don't both of them use PCI, which is a 33 MHz bus? How, then, do they propose transferring data any faster than that? While I may not be a hardware expert, I know that you can't transfer data any faster than that.
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on the coders. I apologize. I've just had serious issues with traffic control in the past, and have encountered significant resistance. However, this does not come from the coders themselves. I do not apologize to the unimaginative buffoons though. If you've ever dealt with the people in charge of state offices, then you probably know what I'm talking about.
I understand the appeal of classical controls. I mean, everything is exact, and there is no uncertainty. You have all of your models and you can design a controller that has a rise time of x, settling time of y, overshoot of z, etc. It's very precise, and appeals to the extremely logical, mathematical nature of most engineers.
However, how accurate is that model? The model is linear, but is it a linear system? No, you have to linearize it. That linearization is only good over a certain range, and after that it fails. A linear model says I can pump 100 A through a 1 ohm resistor, but I know better.
There's also the issue of noise, but the main problem with traffic control is the model. People are highly nonlinear, and their behavior is not easily modeled. Deriving a transfer function for the driving habits of city full of people is an impossible task. The best you can do is come up with probabilities and go from there. Now, I don't know about you, but I find the math involved ugly and cumbersome.
So why not derive a set of fuzzy rules? A simple case is classifying traffic as light, medium, or heavy, which would correspond to short, medium, and long green phases. The math of membership functions is extremely straightforward. Of course, this is an extremely simple example, but intersection control is still fairly intuitive. Anyone sitting at a red light at 3 am can see that nobody's coming, so there's no reason they shouldn't have a green light. With fuzzy logic, you use the same kind of reasoning, and come up with a much more efficient traffic controller. There are some instances where an imprecise approach can lead to much better result, and this is one of them.
The problem is that we have a lot of one-track minded code monkeys writing intersection control software, and a bunch of unimaginative buffoons in charge of the state traffic engineering offices. Believe me, I know from experience.
Stupid French! I could be getting free healthcare right now!
When you spend more than you take in, and rack up more than 7 times more debt than you have assets, and are still operating at a loss, that's a bad thing.
Check out David Walker's address to the National Press Club when it is available. I'm pretty sure he's had a few more economics classes than you have, and apparently a buttload more experience. But I'm sure you'll say that the Comptroller General of the United States know about economics, right?
I keep seeing all these fantastic speeds for ATA and SCSI, but I'm completely confused. Don't both of them use PCI, which is a 33 MHz bus? How, then, do they propose transferring data any faster than that? While I may not be a hardware expert, I know that you can't transfer data any faster than that.