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Video links and a technical discussion here Engineering Tips - Engineering Failures & Disasters - Self Driving Uber Fatality

http://www.eng-tips.com/viewthread.cfm?qid=78116&page=1
FTL
For those of you not in the know, Smokey Yunick was a legendary race car mechanic and Popular Science correspondant. He died a couple of years ago. In March 1983 Popular Science carried a story about an engine he had developed that only had two cylinders and 78 cubic inches but developed 150 hp and got 60 mpg when installed in what looks like a Volkswagon Rabbit. He called it his "adiabatic engine." Supposedly all sorts of car companies were quite interested in the engine.

When I see this I will belive the oil companies have given up.

http://www.eng-tips.com/viewthread.cfm?qid=78116&page=1
FTL
For those of you not in the know, Smokey Yunick was a legendary race car mechanic and Popular Science correspondant. He died a couple of years ago. In March 1983 Popular Science carried a story about an engine he had developed that only had two cylinders and 78 cubic inches but developed 150 hp and got 60 mpg when installed in what looks like a Volkswagon Rabbit. He called it his "adiabatic engine." Supposedly all sorts of car companies were quite interested in the engine.

When I see this I will belive the oil companies have given up.

NYC has low carbon emissions mostly due to the fact that is has the lowest number of cars per person in the US.

I was alluding to that when I mentioned showing me a place down south where I could ditch the car.

Also less heat is lost due to residential areas being more vertically oriented than other parts of the country.

And we don't need the scads of air conditioning that our southern brethren do.

Laminar flow still has friction losses. There's a decent thread over here. It sounds like the "rules of thumb" that they talk about are all on the same order as electrical losses, and obviously depends on the terrain - with a flat run there are no head losses. And of course, each end-user is going to create considerable efficiency losses with each 90 degree fitting :)

Yes it is, o non compos mentis.

No it's not.

Nice Latin by the way. :-)

I am a CET!

So am I.. Are you an apprentice? Google search a reverse current relay. When measuring the phase of the current and voltage forward power is voltage and current in phase up to 90 degrees out of phase depending on power factor. Beyond 90 degrees toward 180 degrees, you are in a reverse current mode feeding power to the source. In a grid tie system, this is normal as you intend to sell power. The industry norm (including driven inducton motors) is to lag the phase. Upon loss of grid, including islanding, the voltage collapses, or you run at a rapidly receeding phase (low frequency) where you relay out for out of tolerance frequency or voltage or both.

They make controllers which monitor the frequency, current and phase just for this application.

Purchase a copy of IEEE Std 1547. It lists the co-gen requirements.

"Cummins peddles cogeneration switchgear for use with their generators and these are based on Basler's cogeneration relay which combines the protective functions that you need. These packages allow you to do both manual and automatic synchronising. Your utility might want to review the schematic diagram and relay features for these cogeneration packages but they are pretty cut and dried. Alledgedly, Basler's relay is smart enough to know when a line is deenergized from the other end when an arcing fault occurs so that the Basler relay will also trip out.

Similarly, inverters for interactive solar generation include a relay that disconnects from the line when there is a power failure and can sense when 1 or more inverters are the sole source of power. Some of this is done with voltage sensing and some of this is done with impedance sensing. That is, the line impedance that a solar inverter sees changes dramatically when the utility opens its circuit breaker or fuse."

From;
http://www.eng-tips.com/viewthread.cfm?qid=145806&page=1

Neil Postman wrote a book called "How To Watch The TV News" in which he proposed that if a media commentator doesn't have a degree in the subject under discussion, a big flashing red sign should be displayed in the background, that says "I don't know what I'm talking about."

Reporters aren't scientists, and they don't know science. What they know is how to write stories that people want to read, because that's their business. I'm not exactly blaming the reporters: they're doing what they're paid to do. The problem is that the people reading the material don't know that reporters don't actually understand the issues, or that the people watching the TV shows let themselves be biased by reporters who don't actually understand the issues.

Carbon fiber/epoxy aircraft can burn, sure. They release toxic compounds when they burn. So does aluminum, and aluminum fires, while rare, are devastating. Carbon fiber has excellent fatigue characteristics: aircraft built from it will probably put 100,000 hours on airframes without any problems, since some carbon fiber fatigue testing setups have had the steel test setup fatigue-fail before the airframe under test while there are lots of aluminum aircraft out there which have failed catastrophically because of fatigue.

People often claim that carbon fiber fails catastrophically while aluminum fails softly. That hasn't been my experience. I spent years racing mountain bikes, and the majority of aluminum failures I had -- although in every case the crack had started well before the failure -- went from imperceptible to completely broken far faster than I could react to, when I was going comparatively slowly at net-near-zero elevation. (RMS elevation on a mountain bike during a race is roughly +1cm, I think...) In contrast, I've had two carbon fiber components fail just as suddenly and one fail comparatively slowly: from the point where it started to break to the point where I got the bike stopped was maybe ten seconds and it was still hanging together by threads of carbon.

When I build a plane it's going to be welded steel tubing, which can be designed with no fatigue limit, but I'd prefer carbon fiber over aluminum if I had to choose.

Engineering Tips is the website with the original online discussion, as referenced in the DesignNews.com story

link to original discussion

link to related items

Unrelated, but possibly of interest:

Link to their Computer Engineers area

Engineering Tips is the website with the original online discussion, as referenced in the DesignNews.com story

link to original discussion

link to related items

Unrelated, but possibly of interest:

Link to their Computer Engineers area

The eng-tips thread mentioned in the article:

http://www.eng-tips.com/viewthread.cfm?qid=159632& page=1

Water has always been more amazing that what people have thought. The fact is that very little is still fully understood about water and that there is much mystery still surrounding it and much research still being put into it.

For instance homeopathy for medicine, whether you believe it or not, have at least confirmed the 'memory' property of water.

Then there is also the case of highly pure (ultrapure) water being able to disolve (corrode) stainless steen and even glass.

We cannot claim something to be suddenly amazing about water until we find it to be mundane first. ;)

Then you might like these links:

Gun aiming computer
nother
US and Japanese versions
a list with links