Displaying 3 results from an estimated 3 matches for "relativistic".
2009 Apr 28
2
Dropping 'empty' panels from lattice
I have 8 cofactors possibly affecting one and only one variable.
I make conditional histograms:
<-pdf(file="tst3.pdf",paper="special",width=36,height=36)
<-histogram(~Oversized|dat$c1*dat$c2*dat$c5*dat$c6*dat$c7*dat$c8*dat$c9*dat$c10,nint=21,layout=c(32,8),data=dat,type="count")
<-dev.off()
This works (compliments to R developers!) but it does generate a
2017 May 24
11
System Time Source
One of our STEM interns recently observed that there are
inexpensive clocks that sync via radio to standard time
services.? This begged a question about why every computer
would not have a radio module to receive time.? Our senior
staff did not have a good answer or if time from such a
radio module would be supported by the operating system.
When I was a student, such questions would have earned
2017 May 24
0
System Time Source
...ons only keep to within about +/- 0.5s per day, with
resynchronisation happening about once a day.
The GPS time system is also notoriously very precisely wrong. The time
was set when the first satellite was sent up and has never been
corrected since - so hasn't taken account of leap seconds or
relativistic effects. All that matters for GPS is that the time on each
satellite transmission is identical, and to that end you can get a
precision of about 3ns (which is what you need to get metre GPS
accuracy) and which you then have to correct for all the various
artefacts since inception. Lower cost GPS re...