11th October 2001Minnerva - GTF Workshop TRIPS, GIS and forecast models Observations and Experience of GTF Issues Miles Logie

11th October 2001Minnerva - GTF Workshop Background Development work with TRIPS software has encountered many issues relevant to GTF Major design activity considered new paradigms for data and software –Object orientation –Components –Data handling –GIS

11th October 2001Minnerva - GTF Workshop Definitions of Objects Need for built-in flexibility –Change is inevitable; polymorphism helps Categories of objects –GTF strong for networks Sufficient for dynamic modelling? –Sufficient for demand modelling? Objects relating to people and freight –Handling different scales Paradigm of changing scales in GIS

11th October 2001Minnerva - GTF Workshop Aids to GTF Object Model Packages –Provide an overview –Makes easier to understand and manage Components –Practical and flexible approach to implementation –Design based around definition of interfaces Compatible with object orientation –Requires librarian of components Spotlights is suitable organisation

11th October 2001Minnerva - GTF Workshop Experience with TRIPS Data transfer –Highway networks, trip matrices, and zonal data is OK –Intersection data, traffic signal data, PT walk/access networks, timetables, etc is not OK Model structure –A distinctive feature of TRIPS –Useful to be able to transfer between applications

11th October 2001Minnerva - GTF Workshop Model Structure in TRIPS

11th October 2001Minnerva - GTF Workshop Further details of structure

11th October 2001Minnerva - GTF Workshop TRIPS experience, continued Command language –Scripts are data too! –Concept of components allows transfer of modelling forms Integration with GIS –Modelling needs simpler networks than GIS presentations Must exploit proprietary network data, e.g. MapInfo’s StreetPro Facilities demonstrated to remove un-required details for model while retaining detailed view for GIS viewing