[LINK] limits of technology in finding someone
Roger Clarke
Roger.Clarke at xamax.com.au
Fri Dec 8 15:25:46 AEDT 2006
At 14:28 +1100 8/12/06, Danny Yee wrote:
>I had an interesting experience the first time I was on a bushwalk
>where the leader had a GPS. ...
I've asked a couple of people to use GPS to nail down the height
difference between my house and the trig on the ridge about 250-300
metres away as the crow flies, and 600 paces in 5 mins 40 secs +/- 10
secs.
No-one's managed to get a decent reading at the house (which has a
clear northerly view, and is 100m above lake-level). Remarkably,
there's also been difficulties getting a consistent reading on top of
the trig, which is treeless (and blessedly telecomms-towerless) and
has vistas in all directions.
I'll stick with the 650m to 725m that I estimate from the local 1:100,000.
The 1:25,000 says 727m, but the house elevation I don't know, because
within the built-up area the contours are smothered by the
cartographer's ridiculous preference for block-boundaries and colour
over topographical information.
--
Roger Clarke http://www.anu.edu.au/people/Roger.Clarke/
Xamax Consultancy Pty Ltd 78 Sidaway St, Chapman ACT 2611 AUSTRALIA
Tel: +61 2 6288 1472, and 6288 6916
mailto:Roger.Clarke at xamax.com.au http://www.xamax.com.au/
Visiting Professor in Info Science & Eng Australian National University
Visiting Professor in the eCommerce Program University of Hong Kong
Visiting Professor in the Cyberspace Law & Policy Centre Uni of NSW
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