On shunting over a hump
نویسنده
چکیده
We consider the situation of rearranging freight trains in a shunting yard with a hump and several tracks. Here, an elementary shunting operation is to push a all cars of one track over the hump. On the way back to the tracks the cars can be guided individually to an arbitrary track. The goal is to create one or several trains that have their cars in a particular order. We measure the efficiency of a shunting plan by the number of elementary shunting operations, and to a lesser extent by the total number of car movements. We find optimal shunting operations in the following situations: – The incoming trains are unsorted and the shunting yard has sufficiently many tracks but the length of the tracks is limited (capaci-
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