Visum

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Visum
Ptvvisum-logo.png
Vendor PTV Group
License Proprietary
Documentation None found online
Data Input TomTom, HERE. OpenStreetMap, INRIX, Shape files, GTFS, HAFAS, VDV 452, DIVA, railML
Data Output Shape files, SVG
Website http://vision-traffic.ptvgroup.com/en-us/products/ptv-visum/



PTV Visum is a transportation modelling software developed by PTV Group. It is a part of a larger software suite that PTV group offers that offer other types of analysis. Visum models transport networks and travel demand, generating forecasts for traffic flows upon which policy and project decisions can be made.

Functions

Visum offers a supply side model of transportation networks. These can include a number of different transportation modes and types of users. The model allows for user-defined objects that adapt the model to meet the specifications of the area being studied. The demand on these networks can be generated using a 4-step model or a tour-based model (powered by Visem). The models include nest modelling and mode choice calculations. In trip assignment, Visum offers a number of options for road and transit assignment. These include dynamic assignment, static models such as toll and node impedance, time-table assignment, headway assignment, etc. These assignments can be run on multiple user classes simultaneously.

Visium is preset to develop a number of reports to visually illustrate model outcomes. Report output includes:

  • Scenario comparison
  • Matrix histograms
  • Flow bundle calculation
  • Interactive shortest path search
  • Isochrones
  • Environmental analyses (noise, emissions)
  • Analysis of accident data

Modules

Some of the functions of Visum are not available in the base software but added as modules. Examples include timetable management and line costing. For a full list of module functionalities see the | Module Fact Sheet.

Potential Uses

Transportation Master Plan

Visum lets users import PrT and PuT networks from a variety of courses. These are used to generate demand models using a variety of methods, including a 4-step algorithm. Various scenarios can then be tested on top of the base case to determine their impact on demand assignment. These scenarios can include changes to roadway, transit, or development.

Result of a PrT assignment: Link bars correspond to volumes by user class Car and HGV, respectively[1]

Public Transit Analysis

Visum allows users to generate networks based on supply and demand data and then verity the network against an existing timetable. The model allows for a graphical representation of each line and for a depiction of the volumes along lines and within the entire network. Demand along specific routes can offer revenue projections and support decisions for changing supply. Since Visum calculates revenue it can also model the changes to revenue as a result of changes to fare and fare structure.

Project Specific Analysis

Visum can model the effects implementing a project will have on a system. This can include the diversions caused by construction and the total traffic flow implications of the project itself. The details from these models can be used as input in cost-benefit analyses of projects and in analyses of environmental impacts. These projects can include changes to roadways, transit, or development.

Runtime

Visum allows for distributed computing among several computers to improve the runtime of its processes.

References

See Also