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CrypticVapor

Member Since: October 26, 2013

Country: United States

  • Hold still, I’ve almost got the neural-net processor integrated.

  • Found an article for calculating the UV Index, it takes into account elevation and cloud cover for the day which I think can be used to calculate back to the fluence rate (which from the short reading, is what this sensor is measuring [mW/cm2] although the formal unit is [W/m2]).

    http://www.epa.gov/sunwise/uvicalc.html

    http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CDQQFjAB&url=http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F230754106_Standardization_of_Methods_for_Fluence_UV_Dose_Determination_in_Bench-Scale_UV_Experiments%2Ffile%2F9fcfd503e8e2026e94.pdf&ei=qcVmU9v2NdGiyASusYGQCg&usg=AFQjCNGzhXJVF2JKwYFcaX_2IkCu7-z_vQ&sig2=WoZTzzL5dX41BKoNj5wKBw&bvm=bv.65788261,d.aWw

  • I am using the following sequence of conversions.

    1) Get the voltage value: ((samples UV) / (samples @ 3.3V)) * 3.3

    2) Get the current UV point based on mx + b. b is a positive offset of 1V (see page 3 of the data sheet “Output Voltage (Shading)”) so we need to subtract it out and the slope I calculated around 8.33 (someone check my math), so:

    ((#1 above) - 1.0) * 8.33

    This will give you a result in [mW/cm2]. I’m not sure if this is a UV Index though, but judging that this sensor ranges between 0 and 15 [mW/cm2] I’d say this very well could be the UV Index.

    Again, someone double check my math….

  • This is the only way I can get her to take a nap.

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