Quantification of Relief Displacement and Effect of Datum Conversion on IRS-1C Image Maps for Undulating Terrain

A luggage structure to which an additional luggage case can be freely added. The luggage structure includes a luggage pull rod and a pair of adjustable latch boards. The luggage pull rod includes a pair of inner tubes, a handle, an engaging board and a base seat. The adjustable latch boards includes an upper pressing board and a base board. The upper pressing board is a reverse L-shaped board body having a vertical section disposed with two latch clips on two sides. Each latch clip is disposed with a through hole for the outer tube to pass thereinto and for a bolt to tighten the outer tube. A horizontal section of the pressing board is formed with several through holes for riveting pin members therein so as to secure the additional luggage case. The base board is an L-shaped board body having a vertical section disposed with two latch clips on two sides. Each latch clip is disposed with a through hole for the outer tube to pass thereinto and for a bolt to tighten the outer tube. A horizontal section of the base board is also formed with several through holes.