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Re: [Ecrit] Location Protocols in Phone BCP
While I think this is generally true, there are reasonably-common
exceptions. For example, on a cruise ship, the fire warden or EMT
cares about the cabin the emergency is in, not the current longitude
and latitude the cabin happens to be located at, which would be
utterly useless. Same is probably true for other "closed" systems,
such as large buildings or an underground mine. Even on a plane, the
flight attendant finds you by seat number when you press that orange
button, not by longitude and latitude, so it doesn't matter whether
you can determine the latter.
Henning
On Nov 21, 2008, at 2:29 PM, Thomson, Martin wrote:
Hi Roger,
To answer this question, you have to first answer the question: how
many reference frames exist? My answer is one.
It helps to only have a single reference frame for this purpose.
That is, earth-centred, earth-fixed is the single reference frame we
use to determine movement. Anything moving in that reference frame
is moving. Establishing ad hoc reference frames increases the
complexity of any solution that we develop.
In the plane example, you might use a complex of the geodetic
location of the plane with uncertainty, plus a civic address with
SEAT=34C. However, this would be considered to be moving at 3500m/s.
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