II. The Intermodal Freight Movement Process

Most freight shipments are intermodal. Virtually all air, waterborne, and non-bulk rail shipments involve more than one mode of transportation. Motor carrier movements are apt to be part of almost all intermodal movements, although motor carrier movements are also the most likely to be uni-modal. Long-haul highway shipments in particular are becoming noticeably more intermodal as trucking companies have shifted line haul movement legs to railroad trailer- or container-on-flat-car movements.[2] This section of the paper relates the intermodal freight movement process to freight identification "events."

A. Freight Terminals and Freight Identification Events

From a freight identification perspective, the most important segment of most transportation movements is in the terminals. Critical transactions are concentrated in terminals, including mode shifts for intermodal movements and changes in the relationship between a freight shipment and its means of conveyance. (For example, in a less-than-truckload (LTL) terminal, shipments arrive in one truck, get sorted, and leave in another truck.) Although many documentation and identification errors begin at the shipment origin, terminals are the focus of operational complexity and they are the place where most problems occur.

"Terminals" covers a wide range of facilities and activities in every mode of transportation. Figure 1, taken from an excellent overview of intermodal freight transportation in relation to intelligent transportation systems, summarizes the kinds of intermodal connections and terminal operations that characterize international freight shipments.[3] By extension, Figure 1 can be used also to describe domestic freight shipments.

Figure 1 encompasses virtually every opportunity for and requirement to apply freight identification technologies:

• Every arrowhead in Figure 1 represents the arrival or departure of a shipment at an origin, destination, terminal, or junction such as a border crossing
• Every box represents at least one internal process transactions that must be recorded—such as the creation of a shipment or the tracking of a small shipment through a container consolidation station
• Almost every connecting line represents a linehaul ripe for position reports about moving transportation equipment—trucks, railcars, planes, ships—and, by deduction, their associated freight shipments.

Figure 1: An Overview of the International Freight Transportation System

All of these movements and transactions call for some degree of visibility and management control. Transportation carriers are concerned about the identification and location of their equipment and the logical connections to customer shipments. Consignors and consignees are concerned about the status of their materiel. The timeliness of visibility information and the degree of management control vary with the value of the freight, the mode of transportation, and the logistics strategy of the customer. However, in almost all cases, technology of some sort is applied to detect, record, or report events such as:

• Key transactions that affect control of or responsibility for a shipment—for example, consolidate, load, unload, arrive, depart
• Changes in condition that affect the integrity of the shipment—breaking a seal, opening a door, spiking temperature
• Regulatory compliance—truck or container weight
• Activity levels or status at key terminals—congestion reports
• Actual equipment or shipment location—referenced to passing a milepost or on a continuous, near real-time basis
  

B. Freight Identification vs. Equipment Identification

Each automated process mentioned in the preceding section identifies and reports on the status of transportation equipment, whether railcars, tractors, or aircraft. The traditional and logical focus of transportation operators is on managing their own assets and operations—focusing on trailers, containers, and railcars; and on tractors, locomotives, aircraft, and ships. The carriers maintain a data file with the current assignments of their equipment to customer loads, and they highlight important shipment characteristics, such as hazardous materials. However, the full detail on the freight itself customarily resides with the consignors or consignees, not the carriers. The difference is reflected in terminology, as some carriers speak of Automatic Equipment Identification (AEI) while some shippers address Intransit Visibility (ITV).

The relationship between transportation equipment and freight is the first in an often complex set of relationships. Freight transportation involves multiple nestings of materiel packages, best pictured as a set of hollow Russian dolls, each stored inside a slightly larger version of itself. Figure 2 illustrates a five-deep set of relationships, one of many possible freight nesting scenarios.[4] Relatively small piece parts are being shipped together to a consignee. Several small shipments are combined in a box or multi-pack. Multiple boxes are combined on a pallet. Multiple pallets are stuffed in a container and a tractor hauls the container. Several methods are available to identify each level of item or consolidation, from plain text labels through simple barcodes to more sophisticated media. In any effective and economical process, each level and each identification serves a useful purpose.

It is important to establish correct nesting relationships as materiel is prepared for shipment, and then to maintain correct relationships as changes occur in the life cycle of a shipment. At a minimum, failure to keep the relationships in order will disrupt intransit shipment visibility and, at a maximum, result in lost or astray freight.

Building and maintaining correct database relationships between nested items is necessary but insufficient for an effective freight identification and status reporting process. Users and their systems also must be able to move easily and transparently across nesting levels and changing relationships to retrieve information as they need it. The need for good access to the information demands effective communication channels for detailed data and transaction confirmations, plus well-integrated application systems and query tools.

Freight identification technologies are rarely of value in and of themselves. Their worth is enhanced or diminished by the total information system and business process of which they are a part. Hence, unless one is concerned only with engineering issues, trends in freight identification technologies must be considered in relation to broader logistics process trends.

Figure 2: Freight Nesting Relationships Illustrating Multi-Level Freight Identification Options

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