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Comment: Re:What about a bus? (Score 1) 279

by Cochonou (#49589509) Attached to: New Study Suggests Flying Is Greener Than Driving
I think you got your ordering wrong. From your source:
The overall energy intensity of the intercity bus mode, which is measured in BTUs (British thermal units) per passenger-mile, is 713, compared with 2,441 for intercity passenger rail (Amtrak); 3,999 for certified air carriers; and 4,238 for public transit buses. Automobiles experience 3,671 BTUs per passenger-mile.

Comment: For a smartphone a TOF camera could be more suited (Score 2) 62

For a smartphones, I'd rather expect so-called "time of flight" cameras to catch-up before LIDARs. Basically, you have an array of LEDs which illuminate the scene using sine or square wave intensity modulation. The imager works at a high framerate (or uses other windowing techniques) to extract the phase shift in each pixel, which gives you 2D ranging information. Of course, there is still the problem of phase unwrapping.
So in this kind of system, you trade off dynamic range for accuracy and cost. As most measurements with smartphones will probably be performed at short distance, this system seems more suitable than regular LIDARs.

Comment: Re:Pilot priorities during an emergency (Score 1) 208

by Cochonou (#49213239) Attached to: A Year On, What Flight Simulators Can't Prove About Flight MH370
Tell me what the plane that went down in the Hudson did? Communicate, aviate, navigate. At least until the decision to go in the Hudson was made, after which there was no need to communicate, and it because Aviate-only. But while crashing (after engine failure), he had a conversation with ATC. That's more important than anything else, despite being last on the list.

Indeed. Now compare this to other recent high profile crashes: AF447 (Rio-Paris, crashed in the middle of the pacific) - no mayday. QZ8501 (Surabaya - Singapore, crashed in the java sea) - no mayday. From these recent events, I wouldn't say that not communicating before regaining control of the aircraft is unusual.

That list is for the Cessna fliers who never have, and never will fly anything else.

I am far for being an aviator. However I got this information from people who do fly airliners. Maybe they are not real pilots, maybe they have been badly trained... but in this case, they are far from being the only ones.

Comment: Pilot priorities during an emergency (Score 4, Informative) 208

by Cochonou (#49210967) Attached to: A Year On, What Flight Simulators Can't Prove About Flight MH370
He added that "the first thing you're going to do" as a pilot during an emergency is "don the oxygen mask" and "confess to ATC [air traffic control], 'We've got an issue, we need to return.'"

This is quite a surprising statement. In an emergency, the pilot priorities are:
1 - Aviate -- Maintain control of the aircraft
2 - Navigate -- Know where you are and where you intend to go
3 - Communicate -- Let someone know your plans and needs
in that precise order, and not in any other order. They are trained to proceed like this.

Comment: Re:Really? Come on now, you should know better. (Score 2) 362

by Cochonou (#49187229) Attached to: Would You Need a License To Drive a Self-Driving Car?
The story of the AF447 crash is precisely that: the human took over, and crashed.
What I wanted to show by bringing up this example is that in current airplane design, there are circumstances in which automation is known to fail (in this case, unreliable/defective sensors). In these circumstances, the systems are designed to give control back to the pilot. The rationale for this is quite clear. It could be argued that fully working automated systems are safer and more reliable than humans. However, automated systems with detected failures are not.
So the pilot is not there to make passengers feel better: he is a part of the automation backup system. Of course, sometimes this backup does not work: no system is perfect.
For automated cars, the situation is a bit different. As you pointed out, drivers are not trained for such contingencies. And if a problem happens, the car can just stop on the side of the road, while the plane does not have this option.

Comment: Re:So far Areva has not delivered anything but del (Score 3, Interesting) 384

by Cochonou (#49187163) Attached to: French Nuclear Industry In Turmoil As Manufacturer Buckles
There is something particular with the EPR and Olkiluoto 3 that is worth pointing out.
For the building of a french nuclear plant, the usual workshare is the following: Areva delivers the reactor equipment, while the EDF utility acts as the prime contractor for the construction of the plant.
For Olkiluoto 3, Areva took the lead, and operated as a turnkey plant manufacturer. This was actually part of a power struggle between Areva and EDF. You can see it did not turn out well.
Newer EPR plants (Flamanville, Taishan) reverted to a more traditional workshare.

Comment: Re:Insurance and registration (Score 1) 362

by Cochonou (#49186923) Attached to: Would You Need a License To Drive a Self-Driving Car?
Yes, the autonomous car would probably be much better in avoiding an unexpected road hazard such as a deer jumping out of the forest. On the other hand, it would probably have more problems to avoid such hazards in a urban environment, since a big part of avoiding accidents in such a context is recognizing potentially dangerous situations before they happen. Computers are not very good currently at recognizing patterns.

Comment: Re:If "yes," then it's not self-driving (Score 2) 362

by Cochonou (#49186633) Attached to: Would You Need a License To Drive a Self-Driving Car?
I would like to see your studies.
In France, the DUI limit is 0.05%. My anecdotical experience is that this threshold does not seem too low: I certainly do not have the same reflexes or spatial awareness when I am close to this threshold. And I do not think this is a corner case.

Comment: Re:And still (Score 1) 196

by Cochonou (#49157677) Attached to: One Astronomer's Quest To Reinstate Pluto As a Planet
You seem to have missed this peculiar characteristic of the 2006 definition of a dwarf planet: it is not a category of planets. Have a look here:

The IAU members gathered at the 2006 General Assembly agreed that a "planet" is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

This means that the Solar System consists of eight "planets" Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A new distinct class of objects called "dwarf planets" was also decided. It was agreed that "planets" and "dwarf planets" are two distinct classes of objects. The first members of the "dwarf planet" category are Ceres, Pluto and 2003 UB313 (temporary name). More "dwarf planets" are expected to be announced by the IAU in the coming months and years. Currently a dozen candidate "dwarf planets" are listed on IAU's "dwarf planet" watchlist, which keeps changing as new objects are found and the physics of the existing candidates becomes better known.

So this definition actually enrages three kinds of people:
- People who think Pluto should be classified as a planet for historical reasons.
- People who think Pluto should be classified as a planet, precisely because as you said, they are many categories of planets which are quite different (terrestrials, gas giants...).
- People who think it is gramatically incorrect for "dwarf planets" not to be "planets".

The perversity of nature is nowhere better demonstrated by the fact that, when exposed to the same atmosphere, bread becomes hard while crackers become soft.

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