a3图幅尺寸:英语翻译

An additional area in which railroads suffer in comparison to motor carriers is equipment availability. Railroad lines use each other’s cars, and at times this equipment may not be located where it is most needed. Railcars may be unavailable because they are being loaded, unloaded, moved within railroad sorting yards, or undergoing repair. Other cars may be standing idle or lost within the vast rail network. A number of developments in the rail industry have helped to overcome some of these utilization problems. Advances have included: computer routing and scheduling; the upgrading of equipment, roadbeds, and terminals; improvements in railcar identification systems; and the use of unit trains, cars owned or leased by the shipper; and dedicated through – train service between major metropolitan areas (nonstop shipments of one or a few shippers’ products). Railroads own approximately 80 percent of their car fleet. The remaining 20 percent are either leased or owned by shippers.