So when estimating static wind load I would recommend using the combined projected frontal and lateral areas - at your vessel's observed max yaw angle. I would then add to this an estimate of the impulse load at max deceleration.

I shall of course be making several phone calls in an attempt to get estimates for this work, but thought I might do as well from the experience of the list members. Any help appreciated. Jim Alexander, Realtor Boatless again (but not for long) Port Charlotte, FL

The wind drag estimates I gave are based on each 100 sq. ft. of area. Remember that you have to multiply the wind drag figure by frontal area/100. Thus, in a 100 kt. frontal wind, the Willard has a drag of 3990 lbs., the N40 a drag of 6384 lbs, the N47 a drag of 7980 lbs, the N72 a drag of 13,164 lbs.

I would love to have some functions that calculate information about the model: facets, edges, estimated hard disk space for a given export e.g. storage_space(type="stl") volume, surface area, principal rotation axes, (output as a matrix?)

Now, if you want to convert your (estimated seconds, estimated nanoseconds) into "real" time, you've got tricky arithmetic to do (with all the roundoff and arithmetic issues to deal with). Ticks = secondscounter*nominaltickrate + subsecondscounter; Realseconds = floor(ticks/actualtickrate) Realsubseconds = remainder/actualtickrate;

On 06/05/2010 01:19 PM, Steve Rooke wrote: > So, at best, it's an estimate. Yes. How good it is, how fast you get it, how much you pay for it and how much effort it is to get and operate is the issue. Getting accurate measurements is hard to prove actually.

For example the OPA653 has a measured PN floor of around -163dBc/Hz for a +13dBm input and the measured PN @1Hz offset is -150dBc/Hz (comparable with the NIST isolation amps).However the voltage noise is (estimated) to be 300nV/rtHz @1Hz and about 8nVrtHz @ 10kHz. Whilst the measured PN floor agrees closely with the measured value.

The > dearth of observatories on Mars suggests the current error bars on > current rate estimates pretty wide. I'd guess the rate estimate is quite good. Wikipedia says 88,775.24409 seconds/sol We can do very good ranging to MER and MSL. Phoenix didn't carry a direct to earth transponder.

It assumes a perfect estimate of the location (no bias from antenna multipath). IT also does not take into account any delay in the antenna or coax to the antenna. Time errors between Glonass and GPS are not included (bad broadcast offset estimate etc). Finally there is the fairly important qualifier of “one sigma” on the 15 ns number.

It's not 100% clear that estimating the frequency using an FFT is unbiased in this case, thus you might get worse (or better) results than what the oscillator actually does. What you are trying to do is spectral estimation from a limited number of samples.