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OCR for page 69
69 A. Characterize B. Identify C. Evaluate constraint improvement options actions Resources Compare projects Links to Mode illustrating sources of Constraint Define low-cost, selected options detailed location quickly Decide on option project Constraint type implementable information Listing of actions constraints Figure 22. Framework of methodology. mainline, siding, terminal/yard, or IT/process improvement. 6.2.2 Selection of Improvements For deepwater ports and inland waterways, the subcategories are deepwater ports and inland waterways, and the constraint This second component of the methodology guides the locations are "on the terminal," "outside the gate," or "water- user to identify the potential low-cost improvement options side" to designate physical zones of operation that require to address the constraint identified in the previous compo- various partners and financial responsibility to implement nent. The first screen in this component of the framework actions that address constraints. displays the definition of a low-cost, quickly implementable The next step is to classify the constraint under considera- improvement specific to the selected mode. tion into one of the three types (i.e., physical, operational, or Once the constraint has been characterized, the user can regulatory). Definitions of the different types of constraints then make a selection from a list of possible options that can are displayed to guide the user in selecting the appropriate be used to address that constraint. The improvement options type of constraint. Figure 23 illustrates one example of apply- displayed are determined by the type of constraint. The list of ing the above steps. improvement options are developed from the results of the lit- For the selected type of constraint, a list of constraints that erature review, interviews, and survey of public- and private- could occur at the constraint location selected are displayed; sector stakeholders. from this list, the user can select the constraint that best fits After selecting the improvement, the user can view exam- the situation under consideration. Standard descriptions for ples of projects implemented without going through the eval- the selected constraint are then displayed as pop-up boxes to uation process (see Figure 22). The user can also select multi- confirm that the selection fits the situation under considera- ple improvements and choose to compare the selected options tion. This step is shown in Figure 24 and illustrated with based on their characteristics or view examples of each option. examples of physical constraints for the highway mode. Sim- Note that the examples of improvements in the database per- ilar lists for the other constraint types and for each mode are tain to the public-sector actions only. Even though improve- included in the database. ments are determined by the type of constraint, it is possible Mode Constraint type Highway Physical Mode subcategory Operational Rail Regulatory Rural interstate Rural principal arterial Deepwater ports & inland waterways Urban interstate Urban principal arterial Constraint Location Intermodal connector Interchange/ramp Intersection Mainline Construction zone Figure 23. Characterization of constraint.

OCR for page 69
70 Definition Constraint Type Definition of Physical constraint Physical Constraints Definition Operational Regulatory Weaving Improvements Turning radii Definition Steep grade a Inadequate capacity b Lane drop c No turning lane etc. Figure 24. Selection of constraint. that some constraints may be addressed by different types of options, on the other hand, are reactions to minimize or avoid improvements. For example, the public sector might imple- the effects of the constraints, but do not remove the con- ment a regulatory action to address an operational constraint. straint. For the rail mode, since ownership of the railroads is For this reason, the improvements are not grouped by type. private, public-sector improvements are limited except for Instead, for each selected constraint, improvements that have regulatory actions. Furthermore, based on information gath- been successfully implemented elsewhere are displayed. Fig- ered, the constraints are more operational or regulatory and ure 25 illustrates this step and shows the relationship between less physical in nature. the first two components of the framework. Freight mobility constraints associated with deepwater ports It is important to distinguish between public-sector and inland waterway modes are influenced to some extent, but improvements and private-sector reactions to minimize the not exclusively, by the highway and rail intermodal links to effects of the constraints. For the highway mode, public-sector the ports. Consequently, some of the physical constraints are improvement options are actions that are designed to remove influenced by these intermodal connectors. Others, however, or minimize the effects of the constraint. The private-sector are totally within the jurisdiction of private- or public-sector Characterize constraint Mode Constraint Type Physical Constraints Weaving Highway Physical Inadequate turning radii Steep grade Rail Operational Inadequate interchange/ ramp capacity Deepwater Regulatory Lane drop ports & inland Etc. waterways Definition of Identify improvement actions Definition of improvement improvement type action Improvement Type Physical Actions Add turning lane Definition of Physical Widen lane improvement Ramp meter type Operational Restriping Etc. Definition of Regulatory improvement action Figure 25. Low-cost improvements based on constraints.