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CHAPTER 3 Drayage Data and Information Sources Data and Information Needs Drayage data are required for the following three basic purposes: To measure and analyze drayage bottlenecks and delays, To evaluate potential solutions and best practices, and To calibrate DrayFLEET or other cost and emissions models. Bottlenecks extend the overall cycle time (e.g., terminal to customer and return) beyond what is necessary to accomplish the actual work of transporting the container. Bottlenecks will thus be manifest as larger-than-necessary cycle times. Identifying and measuring bottlenecks will require data on the overall cycle time, its components, and--especially--those components that contain potential bottlenecks. "Before-and-after" time series data or "with-and-without" cross-section data are needed to eval- uate potential solutions and best practices. Terminal operators often make process or facility improvements to avert the development of significant problems rather than waiting for the prob- lems to develop. The "improvement," therefore, is sometimes only evident in comparing the pres- ent performance with a hypothetically worse performance. Although discussions with drayage firms and terminal operators can suggest likely bottlenecks and sources of delay, more intensive data mining is usually necessary to verify, quantify, analyze, and prioritize the issues. DrayFLEET and other emissions or cost models require data on port characteristics, cargo flows, distances, cost factors, etc. Depending on the issue to be analyzed, data may be needed on the whole drayage cycle, as follows: 1. Travel times to marine terminals, 2. Inbound gate queue times, 3. Inbound gate processing times, 4. Container yard transaction times, 5. Outbound gate queue times, 6. Outbound gate processing times, 7. Travel times to customers (or depots or rail terminals), and 8. Transaction times at customer locations (or depots or rail terminals). Each of these eight generic time segments may need to be investigated in depth and broken down into such levels of detail as are appropriate, supportable, and informative. There are sev- eral potential sources for these data as follows: 16