[LEAPSECS] leapseconds on trains

Rob Seaman seaman at noao.edu
Thu Nov 17 11:52:53 EST 2011


On Nov 17, 2011, at 8:02 AM, Poul-Henning Kamp wrote:


> First: I have an estimate on the recertification cost from a credible industry source.


Citation? Methodology?

…and is recertification actually necessary given the circumstances? This is a shell game. There is no equivalence between the continuation of leap seconds and recertifying s scandal-ridden Danish train project.

And what about the recertification needed when UTC is redefined? The leap seconds are a means to an end. You are assuming that changing the fundamental meaning of UTC itself will have no engineering implications. You previously asserted that nobody in the train industry understands time, but somehow they are credible enough to know that shifting their timebase to TAI will have no implications. Why not just change the clocks right now? Oh, I see - because that would require certification, but changing the clocks in exactly the same way but *calling it* UTC won't.

Yeah, right.


> Second: I have a budgetary price for the ELT


And ELT is one project among many. There is no zero sum equation here.


> Third: I learned division in school.


And both rail and astronomy projects are richly connected to vast numbers of other systems that have always known a world in which UTC meant "Universal Time". "Division" is not the appropriate operation for this exercise in cost estimation and risk assessment.


>> And you don't think they should invest even one penny to understand

>> potential dependencies they have that Coordinated Universal Time

>> remain a type of Universal Time?

>

> If they thought there were a credible indication that any such

> dependencies existed, they probably would.


If the ITU were attempting to inform this and other communities of the issue, they might think to look into it.

Real-world issues will occur whether or not they are aware of the issue and whether or not they regard it as important.

Rob



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