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Comment: Re:Real porpose of the road (Score 1) 226

by bored_engineer (#49348573) Attached to: Russian Official Proposes Road That Could Connect London To NYC

Nobody drives between Los Angeles and Anchorage, except as a road trip just to say they did it.

I've driven between Los Angeles and Fairbanks three times, plus three other trips including one from Austin, TX to Anchorage, AK. Not a single one of the trips was a tourist jaunt. There's also freight that comes up the Alaska Highway.

Comment: Re:moonquakes (Score 1) 111

by bored_engineer (#49302349) Attached to: Giant Lava Tubes Possible On the Moon

I didnt see ay mention of moonquakes.

Did you read the paper? They didn't model any seismic activity, nor did they model any confining stresses. As such, their:

failure values are slightly conservative (i.e. low in magnitude) in order to compensate for [their] not modeling other stress sources such as seismic shaking from meteorite bombardment.

The point of the exercise was to theoretically confirm that large lava tubes can exist because:

Recent in-depth analysis of lunar gravity data from the Gravity Recovery And Interior Laboratory (GRAIL) spacecraft has suggested the possibility of lava tubes on the Moon with diameters in excess of 1 km.

Comment: Re:My LED bulb didn't last! (Score 1) 328

I've been using CFLs and flourescents for 20 years, but continued to use incandescents in a few places because my Mrs. didn't approve. I've managed to win her over with LEDs, though. For the last few days, I've been contemplating whether to replace the vanity light with bulbs similar to those mentioned in the article, or to purchase an LED fixture.

Comment: Re:Becasue... the children! (Score 1) 190

by bored_engineer (#49250787) Attached to: Powdered Alcohol Approved By Feds, Banned By States

Alaska has local option for alcohol imports*. Many of the villages ban it, but many still see a steady flow of booze. It would be impossible to control alcohol movement into villages if it could be smuggled in small sachets.

I'm not trying to run down that Alaska is dangerous, as I've certainly known people maimed or killed by cold or bears.

*For many of the villages, anything they don't make or harvest locally is brought in by barge, plane or barter with other villages 10s of miles away by trails. Much of Alaska has no connection to the road network.

Comment: A load of waffle? (Score 2) 374

by bored_engineer (#49131623) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt
I can't speak to your utility company, but each of the two electricity utilities that I've purchased service from have charged me a monthly fee for the privilege of being connected to its grid. Nor did that utility company pay to connect my house to that grid: I did. Even if I generate an excess, the utility is still compensated for the maintenance of the grid.

Comment: Re:Old news. (Score 1) 285

by bored_engineer (#48660429) Attached to: Study: Red Light Cameras Don't Improve Safety

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

by bored_engineer (#48654723) Attached to: Study: Red Light Cameras Don't Improve Safety

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.

What is worth doing is worth the trouble of asking somebody to do.

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