【正文】 oad a rail boxcar containing 13,000 cases of unpalletized canned goods. With pallets and forklifts, a similar task could be done in about four hours. Better techniques and management units for transferring freight from one mode to another have facilitated intermodal transfers. Early examples include piggyback (TOFC: Trailers On Flat Cars), where truck trailers are placed on rail cars, and LASH (lighter aboard ship), where river barges are placed directly on board seagoing ships.Piggyback and Doublestack Train Cars One of the first attempts at piggybacking dates back to 1872 when the Barnum amp。 Bailey Circus used its own special train of flat railroad cars to tour cities in the United States. It took 3 to 5 hours and considerable effort to unload and load trailers, but the concept remained and piggybacking started to be adopted by railroad operators. By the 1950s piggybacking became increasingly used and a good source of ine for rail panies.Containerization however changed piggybacking to stacking and then to doublestacking where possible. Doublestacking of containers (Container on Flat Car。 COFC) saves much more convoy space than the piggyback method (Trailer on Flat Car。 TOFC) with the added advantage of not to have to carry a trailer. However, several rail lines are not patible with doublestacking because of the required height clearance for bridges and tunnels ( meters). Converting a rail line to doublestacking can be a costly undertaking, especially on the much older European rail system where bridge clearances tend to be lower. In North America, such investments are done over high priority corridors.While handling technology has influenced the development of intermodalism, another important factor has been changes in public policy. Deregulation in the United States in the early 1980s liberated firms from government control. Companies were no longer prohibited from owning across modes, and there developed a strong impetus towards intermodal cooperation. Shipping lines in particular, began to offer integrated rail and road service to customers. The advantages of each mode could be exploited in a seamless system, which created multiplying effects. Customers could purchase the service to ship their products from door to door, without having to concern themselves of modal barriers. With one bill of lading clients can obtain one through rate, despite the transfer of goods from one mode to another.The most important feature of intermodalism is the provision of a service with one ticket (for passengers) or one bill of lading (for freight). This has necessitated a revolution in organization and information control. At the heart of modern intermodalism are data handling, processing and distribution systems that are essential to ensure the safe, reliable and cost effective control of freight and passenger movements being transported by several modes. Electronic Data Interchange (EDI) is an evolving technology that is helping panies and government agencies (customs documentation) cope with an increasingly plex global transport system. Multimodal Transport SystemToday, intermodal transport is transforming a growing share of the medium and longhaul freight flows across the globe. Large integrated transport carriers provide door to door services. The limits of intermodality are imposed by factors of space, time, form, pattern of the network, the number of nodes and linkages, and the type and characteristic of the vehicles and terminals.A multimodal transport system integrates different geographical scales from the global to the local. With the development of new modal and intermodal infrastructure, urban regions have a growing accessibility to the international market。 several parameters of regional transportation are transformed, or at least significantly modified. The above figure represents the regulation of movements of a corridor within a multimodal transportation system posed of a set of peting hub centers where converge regional and local transportation networks. Depending on the geographical scale being considered, the regulation of flows is coordinated at the local level by distribution centers, monly posed of a single transport terminal, or at the global level by articulation points, posed of major transport terminals and related activities.An articulation point can simultaneously have a modal and intermodal convergence of functions。 particularly if it is the interface between several modes. Its modal function relates to its while its intermodal function indicates its level of service. The regional multimodal network converges at major articulation points allowing linkages with the international transportation system through a maritime / land interface. Port cities are the main agent of that function. Containerization has particularly developed the maritime / land interface. It insures flexibility of shipments and several ports have opted for this multimodal transportation technology to keep and consolidate their status of hub center. Containerization IntroductionThe driver of intermodal transportation has undoubtedly been the container, which permits easy handling between modal systems:Container. A large standard size metal box into which cargo is packed for shipment aboard specially configured transport modes. It is designed to be moved with mon handling equipment enabling highspeed intermodal transfers in economically large units between ships, railcars, truck chassis, and barges using a minimum of labor. The container, therefore, serves as the load unit rather than the cargo contained therein, making it the foremost expression of intermodal transportation. The usage of containers shows the plementarity between freight transportation modes by offering a higher fluidity to movements and a standardization of loads. Thus, the relevance of containers is not what they are simple boxes but what they enables。 intermodalism. The reference size is the 20 foot bo