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Comment Re:Old news. (Score 1) 285

Until four years ago, I worked in Los Angeles as a traffic engineer. The ATSAC system is used on more than 4,000 intersections, is interconnected, and makes adjustments to signal timing either manually or automatically. There aren't cameras at all of the monitored intersections, but you don't need cameras to measure traffic volumes and speed, they're just an additional tool.

Further, the systems that use cameras for vehicle detection are falling out of favor. There are too many conditions, such as rain, snow, fog and bright sunshine that can befuddle the systems and cause them to fall back to pre-set timing rather than relying on vehicle detection. Where inductive loops aren't used, radar is proving to be more reliable than cameras.

Even where there's no interconnection, most intersections have controllers that are considerably more sophisticated than simple timers.

Comment Re:Study financed by (Score 1) 285

Three seconds is the minimum duration as per federal law.

What gave you that impression? Signal timing is determined by an equation, but may have some minimum defined by local or state law, or in a design manual.

At 25 MPH with no grade, depending on law or policy, it may be perfectly permissible to have a 2.8s interval, though it's common in practice to round that to a minimum 3s. Here's the equation from the 1999 ITE handbook:
Y=t + 1.467v/2(a+32g), where
t=perception-reaction time, typically assumed to be 1 s,
v=speed in MPH (ITE recommends using the 85th percentile speed, but many agencies use the posted speed.),
a=deceleration rate, assumed to be 10 ft/sec^2,
g=grade.
If you want to read more, NCHRP report 731details recommended guidelines, and provides some history for the recommendations.

Comment Re:I wonder who bought him (Score 1) 216

Ethanol, by itself, has an octane rating of about 129. The octane rating isn't about the energy content of the fuel, but rather its tendency to ignite under compression ("detonate") as compared to iso-octane.

Those tube-shaped sensors can probably measure a bit more than speed. I don't know what is used where you are, but I recently completed the design for a dozen automatic vehicle classification stations. They measure speed, count axles, and of course, count vehicles. I doubt that the sensors you're talking about are for speed enforcement: That's easily done with radar and photos.

Comment Re:Next step - Semiconductors (Score 1) 69

Don't you need to move the spool of abs (or whatever plastic they're using) up there? I don't think this is about the weight that travels up there, but rather the time to deliver parts there. If X plastic widget will get the primary air scrubber(s) working again right now, that vastly trumps relying on a secondary for six months.

Comment Re:My two cents... (Score 5, Informative) 516

I think it'd be fine for utilities to charge something nominal for the privilege of solar.

I couldn't agree more. Where I live, I pay a monthly fee simply to be connected to the grid, whether I use any electricity or not. I assume that if micro-generation becomes common that the co-op must increase this fee. I will happily pay an increased fee to have the night-time and winter generation that are impossible with solar.

Personally, if I could afford solar panels, I'd be interested in what uses it could provide during power outages combined with a battery backup for certain breakers/circuits (fridge, lights, and maybe one for TV watching).

A transfer switch, combined with a good inverter (or a pair, depending on your load) can provide this today. (The transfer switch is mandatory for any solar install, anyway, so as to keep utility workers safe.) In fact, this has been possible for at least 15 years. In fact, a good inverter can act as the charge controller for your batteries, as well as manage a back-up generator to keep the batteries charged during an extended outage. If you want a good system that provides backup power, I would talk to somebody about designing it for you, rather than trying to cobble it together yourself.

Comment Re:Just as long as it's not XK-class. (Score 2) 145

Bad news for me, though. I live at 65 degrees north latitude, and had a power outage for most of a week last winter in November. (That's fall for those of you who have more than two seasons.) There were so many trees in lines and transformers blown that they had to bring parts from outside, and crews from Anchorage. While the temperatures weren't yet brutal, (actually, they never really got there last winter) 0F in November is quite enough to freeze pipes.

Thankfully, I have a wood stove, a slightly abnormal interest in portable lights, and more portable cooking stoves than any one family can possible need. There's one cell tower close to my home, and I charged a large battery and my devices at work each day, so I didn't even lose internet access. I lost running water, but easily melted enough snow for water for drinking, washing and toilet-flushing. I also used snow to keep everything in the refrigerator cold, and moved everything in the freezer outside into a cooler. I was much happier than the neighbors 1/2 mile each way.

Unfortunately, we're facing an unseasonably warm September. I'm not sure what I'll do if power's out for several days right now. I can buy water and dry ice from town, but will the internet pipes freeze up? ;-)

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