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45 Costs of licensing fees and the highly sophisticated This difference in the results can be explained with combi- expertise needed to set up and fine-tune the system. In nations of the factors against another ATCS deployment, addition, it requires lots of vehicle detection that is well- which are shown in Figure 17. maintained and working properly; Difficult to program and data intensive; To determine whether there is any relationship between High cost of supplying communications or low-priority the size of an ATCS and user satisfaction of the agency that sites; and runs the ATCS, responses on the question from Figure 17 Only use it at times of high traffic flows, as standard were divided into two categories. One category represented vehicle actuation is more reactive at quieter times when large ATCS deployments with 50 or more intersections under linking becomes less important. an ATCS and the other category included all other ATCS deployments. The findings showed that approximately 90% Future Adaptive Traffic Control System Deployments of the users with large ATCS deployments would install their systems again versus only 47% of users of small ATCSs. The Approximately 73% of the ATCS users interviewed would findings imply that users with more intersections under an install the same system again. The remaining 27% of the ATCS have a better experience with their ATCSs. The better ATCS users, who would not install the same ATCS, indi- experience is most likely the result of more resources that are cated various reasons for such a decision. The single greatest available to these agencies to operate and maintain ATCSs, problem is the high cost of operating and maintaining an more staff to develop and maintain in-house expertise, and ATCS. Other problems, as shown in Figure 17, included high more attention being given by ATCS vendors. installation costs and a lack of expertise within an agency. Also, ATCS users found, with an approximately equal level SUMMARY of importance, that they did not achieve the expected benefits from their systems and that technical support is weak. Only This chapter identified lessons learned by ATCS users from 5% of the interviewed agencies would not install the same various perspectives such as deployment surprises, hind- ATCS because they are convinced that other ATCSs work sight opinions, factors that influenced ATCS turn-offs, rea- better. Interestingly, when results from Figure 4 and Figure 17 sons preventing ATCS expansions, and potential for new are compared, it can be noted that 79% are satisfied with their ATCS deployments. ATCS agencies were mostly pleasantly systems, but only 73% would install the same systems again. surprised by the system's abilities to provide what was No, ATCS deployment is not No, for other reasons; 3; 6% necessary we did not see expected benefits; 2; 4% No, technical support from vendor is weak; 2; 4% No, we do not have enough expertise within the agency; 4; 8% No, operations and maintenance costs are too high; 6; 11% Yes, we would probably install the same ATCS again; 30; 57% No, installation costs are too high; 3; 6% No, other ATCSs seem to work better; 2; 4% FIGURE 17 Deploying an ATCS again. Would you install the same ATCS in another location?

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46 observed as efficient operations and to adjust to within-day an ATCS (e.g., employing and training the staff). Overall, and day-to-day traffic fluctuations. Negatives were mostly most ATCS users (73%) would install the same system related to difficulties in learning how to operate the system again. This number increases when larger ATCS deploy- and hardware issues (mostly communications). Lessons ments are considered. Smaller systems tend to have more learned can be summarized in four categories: (1) better problems in securing funding and therefore their overall local support from the vendors; (2) better planning for in- experience with an ATCS is not as positive. Major draw- house support; (3) a good preparation of the infrastructure backs for those agencies that would not install the ATCSs (detection and communications); and (4) detailed pre-instal- again are the high costs of operating and maintaining an lation evaluation to estimate operational benefits. When an ATCS (where the emphasis is given to operations and engi- ATCS was turned off it was done for a variety of reasons; neering and not physical maintenance), weak (local) techni- with low operational benefits being one of the major rea- cal support, and that the benefits of running an ATCS are not sons. A major reason preventing ATCSs from further expan- always clearly expressed. The next chapter provides the sions are the high costs related to operating and maintaining conclusions drawn from the study.