Welcome to the latest edition of Caliper Projections for Transportation. We are reinstituting the Projections newsletter in electronic form to keep you better informed about new developments and happenings at Caliper that are of interest to transportation professionals and the broader context in which we all work.

This issue is devoted to the new TransCAD 4.8 and to our new traffic simulation product TransModeler.

TransCAD 4.8 - Dozens of New Features and Speed Improvements

Caliper has been hard at work on two new versions of TransCAD and the first of these is now ready for deployment. TransCAD 4.8 will shortly be released to all commercial users. An academic version will also be forthcoming. The focal points for the 4.8 enhancements were targeted modeling procedure improvements, greater user convenience, and significantly improved computational performance for large models.

TransCAD has the broadest and most advanced tools for multi-modal analysis. In TransCAD 4.8, there are enhanced multimodal utilities including a new screenline tool and a much more flexible and convenient critical (select) link and zone tool both of which work with the multimodal traffic assignment

There is a new and greatly improved centroid connector tool that more fully exploits TransCAD’s GIS capabilities and gives much more user control over the types of connectors that can be automatically generated.

New GIS tools include accessibility calculators for transit and tools to directly utilize imagery from TerraServer and other sources.

A particularly important development is support for compressed matrices. Matrix files will now be significantly smaller in many instances, and some matrix processing and procedures will be faster as a result.

There is support for running two sessions of TransCAD at the same time, so that you can run a model and edit or set up another at the same time. This can also be attractive when using more powerful hardware as will be discussed further below.

There are a variety of new data sets provided including the most up-to-date ITE rates and the latest US Census data. There are enhanced tools that make it easier to make use of the additional data sets including a unique Table Chooser for all of the Census data that might be of interest to transportation planners and an easier way to apply ITE rates for trip generation and attraction. We will soon be providing Streets 2004 to all U.S. TransCAD users. There will also be an updated U.S. road database for freight and other intercity applications.

There are continued refinements to the transit pathfinder and assignment including additional features and reporting options. Transit Pathfinder enhancements include simultaneous skimming of park and ride and walk access in little more time than it takes to perform one skim. Also, path sets for the pathfinder method can now be saved and then reused in the transit assignment leading to further time savings. There is also a new tool for reporting stop to stop transit flows.

There is built-in support for running FTA’s SUMMIT program from TransCAD. This calculates user benefits and can be a very helpful diagnostic tool for model development.

The traffic assignment for signalized and unsignalized intersections is now based on HCM 2000 delay functions. There is also a new intersection control editor that makes it easier to input data for this procedure and the procedure is much faster to compute.

There have been several improvements to the ODME procedure that should produce better results in some situations.

In addition to some minor enhancements to the multi-class, multi-mode assignment, it is now much easier to write your own volume delay functions.

SATURN Support
TransCAD 4.8 works in conjunction with SATURN (Simulation and Assignment of Traffic to Urban Road Networks). Any user with a valid license of SATURN can maintain databases and set up runs from within TransCAD. TransCAD will also post process SATURN outputs and present them as tables and map displays.

Population Synthesis
TransCAD 4.8 includes a population synthesis procedure that can be used for disaggregate and activity-based models. The same procedure has applications for improved trip generation models. In particular, zonal cross-tabs can be created even if they do not exist directly in Census data. Then these cross-tabs can be used in model application.

Multi-threading Arrives!
TransCAD 4.7 was, without question, the overall fastest modeling software in the world. With 4.8, the gap has widened as we have introduced numerous computational enhancements. Foremost among these is that some of the key procedures in TransCAD 4.8, such as the traffic assignments, are now multithreaded, and thus will run almost twice as fast on a dual CPU computer than on a single CPU device. With the advent of multi-core CPUs, this speed acceleration will be available to most everyone and those with greater resources and larger models will be able to use four and eight CPU machines to achieve remarkable speedups.

Distributed Processing
There is also support for distributed processing which provides similar benefits on a network of machines that have high speed interconnections. The setup for distributed processing is more complex and is not automatic as implementation is dependent upon the details of the model. Caliper can assist you in implementing distributed processing for model scripts.

Revised Travel Demand Forecasting Manual and new tutorial exercises
The travel demand modeling with TransCAD manual has been substantially revised and updated to reflect all of these improvements. There are many new or improved tutorial exercises to help users become familiar with TransCAD capabilities.

Moving to TransCAD 4.8 from 4.7
Most models implemented in TransCAD 4.7 will require little or no changes to run in TransCAD 4.8. Some script changes will be needed to take full advantage of some of the new features. Caliper can assist users in making these changes if they so desire.

Under development for more than five years, TransModeler, Caliper’s new traffic simulator is now shipping in beta release. The official release will be available shortly.

TransModeler is a next generation traffic simulation system that is a great advance upon the capabilities of prior simulation packages. TransModeler simulates the movement of individual vehicles in time steps as small as 0.1 seconds. Advanced behavioral models are used for route choice and lane changing. TransModeler also supports a wide variety of ITS features such as traffic actuated signals, variable message signs, lane control systems, etc.

While TransModeler is a microscopic traffic simulator intended for traffic engineers, it can also be used for planning applications and large networks. Moreover, TransModeler can be used in conjunction with TransCAD to evaluate the detailed traffic impacts of planning model forecasts.

TransModeler also has remarkable new capabilities as a GIS for traffic. You can use it to inventory traffic signals and settings and for a variety of asset management applications. If you already know how to use TransCAD, you will find that you know how to use much of TransModeler.

Animated simulation will add impact and understanding to your travel forecasts. The advanced features and GIS capabilities of TransModeler keep things simpler for everyone, from your organization’s traffic engineers, who time the traffic signals, to transportation engineers and planners, who design the roads and forecast demand. Running detailed traffic simulations has never been easier!

More information on TransModeler can be found at www.caliper.com/transmodeler.

TransCAD for the Web provides an ever-increasing set of free templates for implementing transportation applications on the web. These are easily customized and adapted for your use. Two recent custom TransCAD for the Web examples are:

• Scottsbluff Travel Survey: This custom application automates the collection of travel diaries and also captures individual route choice behavior.
• CCTA LOS Calculator: This custom application allows registered CCTA users to compute intersection level of service and produce maps and reports for selected signalized intersections

Training Update

More than 2000 transportation professionals have completed TransCAD training in the last five years. In the past few months, week long courses in travel demand modeling with TransCAD were given in Indiana, Los Angeles, New York City and Stockton, CA.

The next scheduled TransCAD courses in Massachusetts are the weeks of November 12, 2005 and January 17-20, 2006. The latter course is just before TRB and should be convenient for TRB conference attendees.

Upcoming Meetings

Caliper will be exhibiting at the following conferences. If you are attending, we look forward to seeing you.

• European Transport Conference, Strasbourg, France, October 3-5, 2005
• XIII Congres CLAPTU, Lima, Peru, October 3-7, 2005
• AMPO Conference, Denver, Colorado, October 11-14, 2005
• North Carolina Association of MPOs Conference, Greenville, North Carolina, October 26-28, 2005
• TRB, Washington, DC, January 22-26, 2006