In this article we present an industrial application of our mathematical model that integrates
planning and scheduling. Our main objective is to concretize our model and compare the
reel results with the theoretical ones. Our application is realized on a conditioning line of
pharmaceutical products at the ECAM EPMI production laboratory. For this reason and to
save time, we used Witness simulation tool. It gives an overall idea of how the line works,
the Makespan of each simulation and it highlights areas for improvement. We looked for
the best resulting sequence which corresponds to the minest Makespan and total production
cost. Then this sequence is applied on the conditioning line of pharmaceutical products for
simulation. On the other hand, we program our mathematical model with the parameters of
the conditioning line under python in version 3.6 and we adopt a simulation/optimization
coupling approach to verify our model.
This paper reports a new multi-item planning and scheduling problem in a job-shop production
system with the consideration of energy consumption. A mixed integer linear programming
is proposed to integrate planning and scheduling with the consideration of energy
aspect. In this study a new operational constraint is considered in the tactical level because
of the huge interest given to energy consumption and its strong link existing with production
system. To evaluate the performance of this model, computational experiments are
presented, and numerical results are given using the software CPLEX and then discussed.
The rapid global economic development of the world economy depends on the availability of
substantial energy and resources, which is why in recent years a large share of non-renewable
energy resources has attracted interest in energy control. In addition, inappropriate use of
energy resources raises the serious problem of inadequate emissions of greenhouse effect gases,
with major impact on the environment and climate. On the other hand, it is important
to ensure efficient energy consumption in order to stimulate economic development and
preserve the environment. As scheduling conflicts in the different workshops are closely
associated with energy consumption. However, we find in the literature only a brief work
strictly focused on two directions of research: the scheduling with PM and the scheduling
with energy. Moreover, our objective is to combine both aspects and directions of in-depth
research in a single machine. In this context, this article addresses the problem of integrated
scheduling of production, preventive maintenance (PM) and corrective maintenance (CM)
jobs in a single machine. The objective of this article is to minimize total energy consumption
under the constraints of system robustness and stability. A common model for the integration
of preventive maintenance (PM) in production scheduling is proposed, where the sequence
of production tasks, as well as the preventive maintenance (PM) periods and the expected
times for completion of the tasks are established simultaneously; this makes the theory put
into practice more efficient. On the basis of the exact Branch and Bound method integrated on the CPLEX solver and the genetic algorithm (GA) solved in the Python software,
the performance of the proposed integer binary mixed programming model is tested and
evaluated. Indeed, after numerically experimenting with various parameters of the problem,
the B&B algorithm works relatively satisfactorily and provides accurate results compared
to the GA algorithm. A comparative study of the results proved that the model developed
was sufficiently efficient.
Time-of-use (TOU) electricity pricing has been applied in many countries around the world
to encourage manufacturers to reduce their electricity consumption from peak periods to
off-peak periods. This paper investigates a new model of Optimizing Electricity costs during
Integrated Scheduling of Jobs and Stochastic Preventive Maintenance under time of-use
(TOU) electricity pricing scheme in unrelated parallel machine, in which the electricity price
varies throughout a day. The problem lies in assigning a group of jobs, the flexible intervals
of preventive maintenance to a set of unrelated parallel machines and then scheduling of jobs
and flexible preventive maintenance on each separate machine so as to minimize the total
electricity cost. We build an improved continuous-time mixed-integer linear programming
(MILP) model for the problem. To the best of our knowledge, no papers considering both
production scheduling and Stochastic Preventive Maintenance under time of-use (TOU) electricity
pricing scheme with minimization total Electricity costs in unrelated parallel machine.
To evaluate the performance of this model, computational experiments are presented, and
numerical results are given using the software CPLEX and MATLAB with then discussed.