Research on Zero-Wait Scheduling Problems in Multiproduct Processes with Due Dates - Intelligent Computing for Sustainable Energy and Environment - page 326

3.2 The Improved Shuffled Frog-Leaping Algorithm (ISFLA)

Based on the general SFLA, the improved Shuffled Frog-Leaping Algorithm (ISFLA)
for zero-wait multiproduct scheduling under uncertainty is proposed. There are some
key notes in the evolution mechanism of the proposed Shuffled Frog-Leaping
Algorithm.

Encoding Scheme. Taking into account the production characteristics of the zero-
wait multiproduct batch processes, every product is represented by a character, and it
can appear only once in the coding. Then, the sequence of the characters in the coding
is the job sequence.

New Updating Rule in Memeplexes. By using the frog-leaping rule of SFLA, it is
often produced illegal solution for multi-product problems. And if the model has
higher dimension, a feasible solution is impossible by applying the updating rule of
SFLA. The original SFLA will always generate a random solution, which makes the
algorithm more random search.
Therefore, a modified updating rule is devised to ensure that can both produce the
feasible solution and maintain the structure characteristic of the SFLA. This will be
clearly illustrated in Fig. 1.

Fig. 1. The illustration of new frog-leaping rule