4,630 research outputs found
A heuristic approach to incremental and reactive scheduling
An heuristic approach to incremental and reactive scheduling is described. Incremental scheduling is the process of modifying an existing schedule if the initial schedule does not meet its stated initial goals. Reactive scheduling occurs in near real-time in response to changes in available resources or the occurrence of targets of opportunity. Only minor changes are made during both incremental and reactive scheduling because a goal of re-scheduling procedures is to minimally impact the schedule. The described heuristic search techniques, which are employed by the Request Oriented Scheduling Engine (ROSE), a prototype generic scheduler, efficiently approximate the cost of reaching a goal from a given state and effective mechanisms for controlling search
Swarm intelligence for scheduling: a review
Swarm Intelligence generally refers to a problem-solving ability that emerges from the
interaction of simple information-processing units. The concept of Swarm suggests multiplicity,
distribution, stochasticity, randomness, and messiness. The concept of Intelligence suggests that
problem-solving approach is successful considering learning, creativity, cognition capabilities. This paper
introduces some of the theoretical foundations, the biological motivation and fundamental aspects of
swarm intelligence based optimization techniques such Particle Swarm Optimization (PSO), Ant Colony
Optimization (ACO) and Artificial Bees Colony (ABC) algorithms for scheduling optimization
A Multi Objective Evolutionary Algorithm based on Decomposition for a Flow Shop Scheduling Problem in the Context of Industry 4.0
Under the novel paradigm of Industry 4.0, missing operations have arisen as a result of the increasingly customization of the industrial products in which customers have an extended control over the characteristics of the final products. As a result, this has completely modified the scheduling and planning management of jobs in modern factories. As a contribution in this area, this article presents a multi objective evolutionary approach based on decomposition for efficiently addressing the multi objective flow shop problem with missing operations, a relevant problem in modern industry. Tests performed over a representative set of instances show the competitiveness of the proposed approach when compared with other baseline metaheuristics.Fil: Rossit, Diego Gabriel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca. Instituto de Matemática BahÃa Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática BahÃa Blanca; Argentina. Universidad Nacional del Sur. Departamento de IngenierÃa; ArgentinaFil: Nesmachnow, Sergio. Universidad de la República; UruguayFil: Rossit, Daniel Alejandro. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca. Instituto de Matemática BahÃa Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática BahÃa Blanca; Argentina. Universidad Nacional del Sur. Departamento de IngenierÃa; Argentin
Novel heuristic for low-batch manufacturing process scheduling optimisation with reference to process engineering
YesScheduling is an important element that has a major impact on the efficiency of all
manufacturing processes. It plays an important role in optimising the manufacturing times and
costs resulting in energy efficient processes. It has been estimated that more than 75% of
manufacturing processes occur in small batches. In such environments, processes must be able to
perform a variety of operations on a mix of different batches. Batch-job scheduling optimisation is
the response to such low batch manufacturing problems. The optimisation of batch-job process
scheduling problem is still a challenge to researchers and is far from being completely solved due
to its combinatorial nature. In this paper, a novel hybrid heuristic (HybH) solution approach for
batch-job scheduling problem is presented with the objective of optimising the overall Makespan
(Cmax). The proposed HybH is the combination of Index Based Heuristic (IBH) and the Finished
Batch-Job (FBJ) process schedule. The heuristic assigns the first operation to a batch-job using
IBH and the remaining operations on the basis FBJ process schedule. The FBJ process schedule
gives priority to the batch-job with early finished operations, without violating the constraints of
process order. The proposed HybH is explained with the help of a detailed example. Several
benchmark problems are solved from the literature to check the validity and effectiveness of the
proposed heuristic. The presented HybH has achieved batch-job process schedules which have
outperformed the traditional heuristics. The results are encouraging and show that the proposed
heuristic is a valid methodology for batch process scheduling optimisation
Adaptation and parameters studies of CS algorithm for flow shop scheduling problem
Scheduling concerns the allocation of limited resources overtime to perform tasks to fulfill certain criterion and optimize one or several objective functions. One of the most popular models in scheduling theory is that of the flow-shop scheduling. During the last 40 years, the permutation flow-shop sequencing problem with the objective of makespan minimization has held the attraction of many researchers. This problem characterized as Fm/prmu/Cmax in the notation of Graham, involves the determination of the order of processing of n jobs on m machines. In addition, there was evidence that m-machine permutation flow-shop scheduling problem (PFSP) is strongly NP-hard for m ≥3. Due to this NP-hardness, many heuristic approaches have been proposed, this work falls within the framework of the scientific research, whose purpose is to study Cuckoo search algorithm. Also, the objective of this study is to adapt the cuckoo algorithm to a generalized permutation flow-shop problem for minimizing the total completion time, so the problem is denoted as follow: Fm | | Cmax. Simulation results are judged by the total completion time and algorithm run time for each instance processed
Modeling and Solving Flow Shop Scheduling Problem Considering Worker Resource
In this paper, an uninterrupted hybrid flow scheduling problem is modeled under uncertainty conditions. Due to the uncertainty of processing time in workshops, fuzzy programming method has been used to control the parameters of processing time and preparation time. In the proposed model, there are several jobs that must be processed by machines and workers, respectively. The main purpose of the proposed model is to determine the correct sequence of operations and assign operations to each machine and each worker at each stage, so that the total completion time (Cmax) is minimized. Also this paper, fuzzy programming method is used for control unspecified parameter has been used from GAMS software to solve sample problems. The results of problem solving in small and medium dimensions show that with increasing uncertainty, the amount of processing time and consequently the completion time increases. Increases from the whole work. On the other hand, with the increase in the number of machines and workers in each stage due to the high efficiency of the machines, the completion time of all works has decreased. Innovations in this paper include uninterrupted hybrid flow storage scheduling with respect to fuzzy processing time and preparation time in addition to payment time. The allocation of workers and machines to jobs is another innovation of this article
Total Tardiness Minimization in a Single-Machine with Periodical Resource Constraints
In this paper we introduce a variant of the single machine considering resource restriction per period. The objective function to be minimized is the total tardiness. We proposed an integer linear programming modeling based on a bin packing formulation. In view of the NP-hardness of the introduced variant, heuristic algorithms are required to find high-quality solutions within an admissible computation times. In this sense, we present a new hybrid matheuristic called Relax-and-Fix with Variable Fixing Search (RFVFS). This innovative solution approach combines the relax-and-fix algorithm and a strategy for the fixation of decision variables based on the concept of the variable neighborhood search metaheuristic. As statistical indicators to evaluate the solution procedures under comparison, we employ the Average Relative Deviation Index (ARDI) and the Success Rate (SR). We performed extensive computational experimentation with a testbed composed by 450 proposed test problems. Considering the results for the number of jobs, the RFVFS returned ARDI and SR values of 35.6% and 41.3%, respectively. Our proposal outperformed the best solution approach available for a closely-related problem with statistical significance
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