[Talk-ko] expressway 1 and some thoughts

[Robert Helvie]

OK,

So I "adopted" expressway 1 some time ago and have been working on it off
and on for a while. I guess it is probably as finished as I can get it for
now. I went through and connected all the exits and interchanges, matched
things up with the Yahoo imagery or GPS data when/if needed, corrected
incorrect oneway information, removed duplicate ways, and paired up nodes
where appropriate.

It should be clean from then end (start?) in Busan all the way up past
Suwon. I started checking it a little way into Seoul, but the interchanges
there are many, and I figured there might be some mappers in Seoul who could
better see/understand the unders, overs, ons, and offs because they are on
the ground there.

The Yahoo imagery isn't perfect of course, but in some places it is all we
have, and even then it is not enough. In fact here <
http://www.openstreetmap.org/?lat=35.8846843242645&lon=128.692710399628&zoom=15>
the imagery is old and doesn't reflect the info you can see on other maps.
The expressway exit no longer exists. And, unfortunately, there are no GPS
data points for the actual interchange. I started to match the construction
that can be seen, but I decided to leave it for another mapper. Someone
should eventually go out and drive the different roads so we can get a
better picture of things.

The lack of GPS data brings up another point. It is not necessary, of
course, but it is good practice to upload your traces when possible. It is a
good idea to put up any GPS data you have that way others can work on the
map if you are not able and additionally, if any ways come into question,
their validity can be backed up by the GPS traces in the database.  I rarely
see GPS traces go up for Korea. Or perhaps there are some, but they are not
being tagged. Just as a suggestion, I tag my traces with country (Korea),
city (Daejeon), and 'gu' and 'dong' if I remember where I was riding. If you
are worried about privacy, traces can now be totally anonymous if desired.

One final point ... It is probably a good idea, if you use Yahoo imagery, to
add the tag 'review:no' to ways you actually draw. That way if/when someone
actually does drive/ride the roads, they can go back, make any corrections
and then delete the 'review:no' tag and people will know that the road
doesn't need to be checked again.

Just some thoughts. As OSM says ...

Have fun.

Robert

"We should give meaning to life, not wait for life to give to
give us meaning. "
~ unknown
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