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Comment: Re:OR (Score 1) 578

by hankwang (#47369417) Attached to: Unintended Consequences For Traffic Safety Feature

"Advanced driving courses teach vehicle dynamics, skid control, proper reactionary techniques to road hazards, proactive hazard evaluation, and so on; they cost $300 here, and you can go all the way to $1500 for driving/racing combined classes"

That's cheap. Here in Netherlands, a regular driving license will cost you around 30 hours(*) of instruction, plus 10 or so hours to study the traffic rules in all kinds of edge cases, and about 1500 euros for instruction, theory exam, and driving exam. It doesn't include skid control.

Traffic fatalities (per capita) are a factor 3 lower in Netherlands and Germany, compared to the US.

(*) it took me more like 75 hours of instruction and considerably more money... started at later age and generally bad body coordination/multitasking....

Comment: Re:How much reduced sleep is tied to long commutes (Score 1) 710

by hankwang (#47313049) Attached to: Workaholism In America Is Hurting the Economy

"I know people who are losing two hours of their life a day commuting each way, "

I commute well over 2 hours, 4 days per week. I don't see it as lost time. I'm reading slashdot and other sites in the train like now (plenty of space since I travel after the peak hours). In addition, 15 km of cycling per day, which is my only exercise. Fortunately the climate over here allows cycling.

But the idea of driving a car for 2 h/day horrifies me...

Comment: Re:Stronger than steel made from wood! (Score 1) 82

I don't think you quite understand.

Wood is an excellent engineering material, it's widely used in construction, and can and has been very successfully used for ships, aircraft etc. During WWII, even when aluminium alloys were available, British designers used wood, to make very highly successful, fast, and very robust aircraft like the de Havilland Mosquito.

Yes, of course you have to consider multiple properties, but actually, wood is very good under lots of different properties, particularly compression, and wood in general and balsa structures in particular have *surreal* rigidity. See this table:

so by weight, balsa is the most rigid material known, by a long, long way.

Comment: Re:Stronger than steel made from wood! (Score 1) 82


Look down the list for stainless steel... then carry on down to 'balsa'.

Yup. Wood has a better strength to weigh ratio than stainless steel. (Only along the grain though but plywood fixes that, and you can put the strength in the direction you need it.)

Although they're not in the table, other woods are similar, but more dense.

Comment: Re:gullwing doors (Score 1) 136

by WolfWithoutAClause (#47195849) Attached to: Tesla Makes Improvements To Model S

Rocket engines very typically ARE internal combustion engines.

The definition of 'internal combustion' is that the pressures from the combustion gases cause the motion. (In external combustion engines, such as steam engines, the heat from the combustion goes through a heat exchanger and the working fluid on the other side of that does the work.)

In a rocket the exhaust gases push directly on the exhaust nozzle, and the interior of the combustion chamber and causes the motion, making it an internal combustion engine.

Some rockets (such as nuclear-thermal or solar-thermal rockets) do have a heat exchanger, and are not internal combustion engines, but not the common ones.

Comment: Re:From many points of data (Score 2) 772

by WolfWithoutAClause (#47107383) Attached to: Belief In Evolution Doesn't Measure Science Literacy

Yes, isn't believing in the truth of something that has been rigorously proved part of scientific literacy?

What would happen if the ones that don't believe humans evolved were forced to deal with some of the unequivocal data that backs it up, like genetics, would they still deny it and cause practical problems?

Further it raises the question as to who is trying to change the test, and why ;)

Comment: Re:Oblig Prior Art Question (Score 1) 56

by hankwang (#47082943) Attached to: Questionable Patents From MakerBot

When a patent is filed, I believe the USPTO keeps it confidential for a long time (a year?) until it is well along in process, to avoid revealing its secrets long before the patent is decided.

In the standard procedure, the application is kept secret for 18 months; then the application is published; the USPTO will then wait another year or so (depending on the back log it could be much more) before deciding whether or not to grant the patent. In this time slot between publication and decision, competitors could point out relevant prior art to USPTO, which would affect the decision.

In the US system, one can also file a provisional patent application and wait 12 months before filing the final application, which will essentially stretch the confidential period from 18 to 30 months. This was the case here. The final application can differ from the provisional application (errors corrected, more examples provided, reworded claims, etc.). In case of relevant prior art that was published between the provisional and final application, the provisional application will count.

Weekends were made for programming. - Karl Lehenbauer