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Intermodal Transportation
Network
This
web page contains five different data systems available for distribution:
1. ck - The intermodal network with county centroids
plus the four component modal networks and terminals used to construct
it:
2. nh - Oak Ridge National Highway Network
3. qc - CTA operational railroad network
4. ws - National Waterways Network with attached global seaways
5. Intermodal terminals
The individual modal networks are provided primarily to support users
who wish to modify network ck, most commonly to calculate different link
impedances, and must refer to original elements in order to do so. The
component networks are therefore provided only in standard ascii form.
For alternate formats and later versions of these networks, consult their
separate web pages.
We expect a range of expertise and intentions on the part of users. To
accommodate this range, the Intermodal Network comes in two forms:
1. cks - A standard ORNL version, described in accompanying documentation,
contains the complete range of data in the system, but is difficult to
use except in custom-written programs. This is the form that will probably
be most convenient for users who have or wish to create their own network
analysis programs, or who wish to modify data values.
2. ckg - GIS versions should be importable into TransCAD or Arc/Info with
modest effort for the casual user.
The
Arc/Info version includes ascii link and node location and attribute files,
the Arc/Info macro that will create link and node covers, and export versions
of the covers (which may be imported into ArcView and some other GIS systems).
The Maptitude/TransCAD version contains
the link and node location and attribute files and the attribute dictionaries
suitable for creating layers.
Attribute files are identical for all GIS
versions. Geographic coordinates are in decimal degrees (no projection),
datum NAD27. Although the network should be "routable" in any
GIS, users are cautioned about the use of native impedances and unrestricted
centroid connections (see documentation).
Since the component network qc94 did not reflect the recent Conrail restructuring
at the time this network was assembled (Feb 2000), the effective date
of the composite network is May 1999.
The following two data systems are not documented on independent web pages:
1. The ws waterway network uses the same
BTS format, and the same variables, as were included in the distribution
of the National Waterways Network on the National Transportation Atlas
Database CD-ROM in early 1997. There is no documentation. The documentation
in the NTAD should be adequate, and is downloadable from their website
www.bts.gov. Network 'ws' is simply the NWN with selected links and attachments
from the global seaways network concatenated at the bottom.
2. ORNL terminals - There are two comma-delimited
data files (BTS format) with variable names listed in the first (comment)
record of each. Documentation is included.
It is unlikely that any user would wish to download every file on this
site. Typical users who write their own programs will download (or
print) the ck documentation Cnetdoc.txt and download the cks network files.
Serious users who write their own impedance functions will also download
the component modal networks. A typical ArcView user will download the
ckg export files (.e00 extension) only.
Contents of the Intermodal Transportation Network:
| cks
(standard) |
ckg
(GIS version) |
|
| |
Maptitude |
Arc/Info |
|
| cks02hrw.llp |
ckg02ll.txt |
ckg02hrw.lla |
link
attributes |
| cks02hrw.lcp |
ckg02lc.geo |
ckg02hrw.lca |
link
locations |
| cks02hrw.ndp |
ckg02nd.txt |
ckg02hrw.nda |
node
attributes |
| . |
ckg02nc.geo |
ckg02hrw.nca |
node
locations |
| . |
ckg02ll.dcc |
rcap.aml |
link
attr dict |
| . |
ckg02nd.dcc |
download |
node
attr dict |
| . |
. |
|
cover
creation |
| . |
. |
ckg02lvd.e00 |
link
cover |
| . |
. |
ckg02nvd.e00 |
node
cover |
| download |
download |
download |
|
| nh
- |
highways |
download |
| |
Standard
format |
|
| |
nhpa1us.lnk |
link
attributes |
| |
nhpa1us.nod |
node
attributes |
| |
|
|
| qc
- |
operational
RR network |
Temporarily
unavailable |
| |
Standard
format |
|
| |
qc94us.llr |
link
attributes |
| |
qc94us.lcr |
link
locations |
| |
qc94us.ndr |
node
attributes |
| |
qc94us.iln |
interlines |
| |
|
|
| ws
- |
waterways |
download |
| |
BTS
format |
|
| |
ws79.lnk |
link
loc/names |
| |
ws79.tl1 |
link
attributes |
| |
ws79.geo |
link
locations |
| |
ws79.nod |
node
loc/names |
| |
ws79.tn1 |
node
attributes |
| |
|
|
| Terminals |
|
|
| download |
terminal.chm
|
on-line
help |
| |
ortrm02.nod |
trm
loc/names |
| |
ortrm02.atr |
trm
attributes |
Note: Files with an extension of 'lnk'
(ie, nhpa1us.lnk and ws79.lnk) may not appear in a Windows directory listing
because they are assumed to be shortcuts.
CTA Transportation Networks - Home
Page
Revised August,
2000 WebMaster ORNL Disclaimer
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