For the purpose of solving the flexible job-shop scheduling problem (FJSP), an improved quantum genetic algorithm based on earliness/tardiness penalty coefficient is proposed in this paper. For minimizing the completion time and the job-shop cost, a simulation model was established firstly. Next, according to the characteristics of the due in production, a double penalty coefficient was designe...

Crossover operators that preserve common components can also preserve representation level constraints. Consequently, these constraints can be used to beneficially reduce the search space. For example, in flow shop scheduling problems with order-based objectives (e.g. tardiness costs and earliness costs), search space reductions have been implemented with precedence constraints. Experiments sho...

We examine the problem of scheduling jobs, on a single processor to minimise the total earliness and tardiness costs about a common due date. Jobs belong to mutually exclusive families and a sequence independent setup task is required when processing switches from a job of one family to a job of another. We extend earlier results to obtain necessary optimal conditions for this problem. These ar...

In this paper we investigate scheduling problems with a deteriorating and resource-dependent maintenance activity on a single machine. The duration of the maintenance is assumed to be dependent both on its starting time and on the resource allocated to it. The objective is determining the job sequence, the position to perform a maintenance activity and the amount of additional resource allocate...

Background One of the Millennium Development Goals (MDG’s) targets is improving reproductive and sexual health especially on adolescents. High-risk sexual behaviours like earliness of initiation of sexual intercourse in adolescents will have bad impact on their future. We need to explore the predictors of premarital sexual intercourse in adolescents based on theoretical framework. This study ai...

This paper addresses a one-machine scheduling problem in which the efficiency of the machine is not constant, that is the duration of a task is longer in badly efficient time periods. Each task has an irregular completion cost. Under the assumption that the efficiency constraints are time-periodic, we show that the special case where the sequence is fixed can be solved in polynomial time. The g...

This study proposes an exact algorithm for the precedence-constrained singlemachine scheduling problem to minimize total job completion cost where machine idle time is forbidden. The proposed algorithm is an extension of the authors’ previous algorithms for the problem without precedence-constraints and is based on the SSDP (Successive Sublimation Dynamic Programming) method. Numerical experime...

We present a new mathematical model for a permutation flowshop scheduling problem with sequence-dependent setup times considering minimization of two objectives, namely makespan and weighted mean total earliness/tardiness. Only small-sized problems with up to 20 jobs can be solved by the proposed integer programming approach. Thus, an effective multi-objective immune system (MOIS) is specially ...

Ethephon sprayed directly onto pepino fruits (Solanum muricatum Ait., Chilean clone CH8) at 1920 mg lÿ1 advanced colour changes and therefore earliness of the crop. Colour changes evaluated with a HunterLab colorimeter occurred more quickly in ethephon-treated fruits in which a*/b* ratio changed soon after treatment and reached the highest values in treated fruits. Among four visually classifie...

This study investigates the single-machine scheduling problem with common due-win -dow assignment, past-sequence-dependent (p-s-d) setup times and a deteriorating maintenance activity. By past-sequence-dependent setup times, we mean that the setup time of a job is proportional to the sum of the processing times of the jobs already processed. The objective is to minimize a cost function based on...