Archived Data User Services (ADUS)

1. Archived Data User Services (ADUS)

2. ITS Produce Data • The (sensor) data are used for to help take transportation management actions • Traffic control systems • Transit vehicle performance improvements • Traveler information • Commercial vehicle operations improvements • Etc…

3. So, • Did those management actions actually improve travel? • Could you have done better? • Were the assumptions you used when you built the system valid? • Are there other actions you could take?

4. To Answer Those Questions • Collect, store, and use the ITS data you generate to • Understand the performance of the transportation system • Understand the performance of your management systems • Feed the analysis efforts that examine ways to improve the transportation system

5. ADUS • Management of the transportation system can not be done without knowledge of its performance • You can’t manage what you can’t measure

6. What you measure gets managed

7. ADUS • We are now beginning to store the data we already collect • The next step will be to actually use the data we store to improve management of the system

8. ADUS • The difficulty comes not from collecting ITS data but from storing the data and making the stored data useful

9. ADUS • Data storage and use requires an archive system • Data collection • Data transfer to the archive • Data storage (aggregation?) • Analysis and reporting • Quality assurance • Integration with other data sources • Database management

10. ADUS • ITS systems produce data – already - often continuous data • Large volumes of data are: • Difficult to handle • Expensive to store and manipulate • Not something DOTs are used to dealing with

11. ADUS • The collection of data for data’s sake is a waste of money • Collecting data is only a good idea, if you intend to use it

12. ADUS • To maintain a useful archive (they’re expensive), the key is: • Does the data you collect help you run the system more effectively? • Decision support • Performance reporting

13. ADUS • Data can be used for • Operations planning • Maintenance planning • Safety analysis • Facility performance monitoring • Policy analyses • Congestion monitoring • Systems planning • Environmental analysis

14. But are the data actually used for those purposes?

15. ATMS – Types of Data Available • Vehicle volumes • Vehicle speeds • Travel time measurements • Origin / destination patterns (from tolls) • Incident locations and durations • A variety of more specialized data items • Volumes by various vehicle classifications

16. APTS – Types of Data Available • Transit ridership • Transit vehicle performance • Vehicle maintenance performance • Signal system performance

17. ITS Data • Continuous data allows measurement of transportation system performance variability • Reliability is a key to management of the transportation system

18. ITS Data Are Different • Allows more detailed analysis • Requires creativity

19. Why Creativity? • ITS often provide different (better) measures of performance than traditionally used

20. An Example of Using an Archive Freeway Performance Data Used for Policy Analysis (Are our policies doing any good?)

21. Traditional Performance Measures • Do not describe the complexity of what is happening on the roadway • Are not easily understood by most decision makers and/or the public

22. Traditional Performance Measures • Reported measures traditionally are: • v / c ratios • Usually based on limited data, and a poor mechanism for showing changing conditions during the day • LOS • Hard for non-technical people to understand • Based on limited data • Travel time and delay • Often based on very limited sample, or some very imperfect calculations

24. Improved Performance Measures • This allows you to illustrate some very important trends to a general audience in non-technical terms

26. Improved Performance Measures • But volume alone does not tell someone whether the facility is working effectively • Color coding speed information on top of volume data yields a more descriptive picture of performance

29. Improved Performance Measures • Unfortunately, averaging speeds over many days often hides the fact of how often a facility is congested

31. Improved Performance Measures • We display that information based on the percentage of time a facility falls below a designated speed

32. Freq. Of LOS F (stop and go)

33. Improved Performance Measures • This can show you what happens when a major change in freeway operations takes place • In this case a switch from outside to inside HOV lane operation • It also illustrates other trends

37. Improved Performance Measures • But freeway performance varies significantly from location to location

41. The Effect of Starting AM Ramp Metering on SR-520 2001 Congestion LOS F occurs 1 day per week less often 90 2000 1999 Congestion 2001 Volume 1800 80 1999 Volume 1600 70 1400 60 1200 50 170 veh / hr / ln improvement Frequency of Congestion Hourly Volume Per Lane (vplph) 1000 40 800 30 600 20 400 10 200 0 0 5:30 AM 7:30 AM 9:30 AM 11:30 AM 1:30 PM 3:30 PM 5:30 PM 7:30 PM Time of Day

42. Improved Performance Measures • This means that it is important to • Choose your location carefully • Report on multiple locations • Report on geographic variation • So we developed a geographic illustration of traffic performance

43. Traffic Profile SR 520 General Purpose Lanes 1997 Weekday Average West bound Ea st bound NE 60th St. 148 th Ave. 405 B’vue. Way 92nd Ave. 84th Ave. 520 Lk. Wash. Arboretum Montlake Blvd. 5 0 2 4 6 8 10 12 2 4 6 8 10 12 0 2 4 6 8 10 12 2 4 6 8 10 12 AM PM AM PM Time Time Uncongested, near Restricted movement More heavily congested, Extremely congested, speed limit but near speed limit 45 - 55 mph unstable flow

44. Improved Performance Measures • Geographic illustration can be • Volume • Speed • Lane occupancy • Other

49. Improved Performance Measures • The basic geographic by time of day matrix allows us to compute travel times starting every five minutes, 365 days per year • These travel times can then be summarized