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12453
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location Vancouver, Canada
age 45
visits member for 4 years, 4 months
seen 2 days ago

VP Research&Development at an image guided surgery startup.

Mostly do C++,python,image processing,machine vision - anything with lots of 3D,maths and data. Background is experimental physics and optics.


Jan
5
comment What fundamental principles or theories are required by modern physics?
@Ron - then the results can't be true! The point is that any 'impossible' result must still allow all current experimental results.
Jan
5
answered What fundamental principles or theories are required by modern physics?
Jan
4
comment How to calculate a firing location from point of impact data?
it works pretty well for a ballistic trajectory, like an artillery shell from only two points - especially if you know the muzzle velocity from the calibre
Jan
4
comment Why does the water rise?
@leonbloy - although with a smoky candle you do get a lot of CO. Plus since O2 is only 20% of air it would at most be a (1-0.65)*0.21 = 7% change in volume even with full combustion
Jan
3
comment Why does the water rise?
As oxygen is burned - how many moles of CO2 do you get for each mole of O2 used?
Jan
3
revised That 10km/day error predicted if GPS satellite clocks not corrected for relativity
added 276 characters in body
Jan
3
comment Limit of human eye flicker perception?
Then anything faster than 50hz would probably be OK. Another trick is a single PWM to modulate the common supply to all the leds (via a switching transistor)
Jan
3
comment Is it humanly possible to change Earth's axis?
We do make measurable changes simply by filling/emptying dams - but only because we can make immensely sensitive measurements (eg radio VLBI)
Jan
3
comment How to calculate a firing location from point of impact data?
But if it went through the ceiling at any sort of arc it's probably falling at terminal velocity so difficult to get a good solution
Jan
2
answered Limit of human eye flicker perception?
Jan
1
revised Heat transfer speed - affected by difference in relative heat?
added 30 characters in body
Dec
31
answered Heat transfer speed - affected by difference in relative heat?
Dec
31
comment How to guess the content of a christmas present?
Only true for solid objects though, you could tell if it was a bottle of liquid rather than a block of glass. You should also be able to measure the viscosity - at least enough to know it's a bottle of wine or cough syrup.
Dec
30
answered Effect of coarse vacuum on consumer electronics?
Dec
27
answered Why do the planets' orbital distances fall on an exponential curve?
Dec
24
answered How much effect does the mass of a bicycle tire have on acceleration?
Dec
23
comment Why can't airplanes just keep going up?
@Jonathon - some heavy transports used disposable rocket boosters (JATO) to help takeoff from short runways. But basically anything that flies in air uses air, it's cheap and widely available and you don't have to carry it!
Dec
23
comment Why can't airplanes just keep going up?
There is no real difference between a turbojet on a fighter and a turbofan on a 747 - they both need air to burn.
Dec
23
answered Why can't airplanes just keep going up?
Dec
22
comment Is electricity instantaneous?
Ironically the cable company here is promoting it's new fibre service as internet at the speed of light. Light goes 1.56 times slower in glass than electricity does in some types of coax