Emissions
The most recent TMODEL2 update went out in June as scheduled. This latest update included the ability to export emission information to the link file. This then allows you to plot and further analyze just where your emission problems are. We have been using this and find that the analysis of emission locations adds a very interesting dimension. Because it is a combination of vehicle-miles traveled and operating speed, the impact of transportation system improvements are much more apparent. Give it a try.
Subarea Windows
The new update also included the ability to "cut" a subarea out of your larger model by merely selecting lower left and upper right coordinates. If you are detailing a window of your regional model, simply do a plot of the area you want to window in on. Read the coordinates off the plot, select the new menu option 1.7.4, enter the coordinates, and you have a subset of your existing model with which to work. The nodes are all renumbered, and the links that connect to the two nodes included in the window are renumbered to match the new node structure automatically. If you want to also create a subset of your layer file, see section 4.4.9.6. Remember that if you want to extract the through-trip table for the subarea, you can perform a subarea select link analysis with one run using section 3.11. This module will provide the through movements as well as I-X and X-I volumes for the subarea.
Other significant items to note are the ability to list link specific screenline comparisons, link data equations, and the ability to export layer files to .DXF format.
Windows Windows
Work is continuing on TMODEL for Windows. We have not decided what to call it for sure, but it keeps coming out in our programming as TMODEL3. Many of you have asked about it. To answer the most significant question , "What will it cost?", those of you who have current TMODEL2 maintenance will receive all new modules at no charge. We are aiming at Windows95 and WindowsNT. Several of the programs will work with Win3.1 or Win3.1 with Win32s (which allows it to run 32-bit applications).
Two preliminary programs were released with the June update. They are for use in analyzing the importance of the different coefficients for the Link and Node Delay functions. We have been using these in-house for awhile and find them to be very useful in adjusting the speed and delay functions.
A Beta test version of the Distribution and Assignment module we have been working on is on the BBS. It currently performs an integrated distribution and assignment for large models, completely in RAM memory. It is written in 32-bit mode, uses real numbers, and keeps all arrays in memory for maximum speed. If you want to test it out, it is called TM3DNA.ZIP on the BBS.
The above may be sort of exciting, but what really has us excited are the new features we are working on adding to it. The most exciting one is what we are calling MPA or Multi-Point Assignment. This will allow you to load a zone at multiple points on the network, not just at one zone centroid, even to assign intrazonal trips if you wish! The advantage is much better turning movement and link assignment. In essence, it will operate as if you had about 4 times as many zones as you do have without the problems caused by having more zones.
Watch for more in the next newsletter, or call the BBS (206) 463-2133, and look for what is new.