Campbell CR6 Series, Operator'S Manual

Page: 268 / 690

Section 7. Installation
268
Equating the two expressions for Cos (θ') and using the previous equation for s
i
;
Solving for (Θ
i
')
2
, one obtains;
Summing (Θ
i
')
2
over N samples and dividing by N yields the varianc e of Θu.
Note The sum of the last term equals 0.
The term,
is 0 if the deviations in speed are not correlated with the deviation in direction.
This assumption has been verified in tests on wind data by Campbell Scientific;
the Air Resources Laboratory, NOAA, Idaho Falls, ID; and MERDI, Butte, MT.
In these tests, the maximum differences in
and
have never been greater than a few degrees.
The final form is arrived at by converting from radians to degrees (57.296
degrees/radian).
7.7.10 Data Output: Writing High-Frequency Data to Memory
Cards
Related Topics:
•
Memory Card (CRD: Drive) — Overview
(p. 86)
• Memory Card (CRD: Drive) — Details
(p. 495)
•
Memory Cards and Record Numbers
(p. 500)
•
Data Output: Writing High-Frequency Data to Memory Cards
(p. 268)
• File System Errors
(p. 512)
•
Data Storage Devices — List
(p. 661)
•
Data File Format Examples
(p. 498)
•
Data Storage Drives Table
(p. 492)