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The manufacturing sector faces unprecedented challenges, including intense competition, a surge in product varieties, heightened customization demands, and shorter product life cycles. These challenges underscore the critical need to optimize manufacturing systems. Among the most enduring and complex challenges within this domain is production scheduling. In practical scenarios, setup time is whenever a machine transitions from processing one product to another. Job scheduling with setup times or associated costs has garnered significant attention in both manufacturing and service environments, prompting extensive research efforts. While previous studies on customer order scheduling primarily focused on orders or jobs to be processed across multiple machines, they often overlooked the crucial factor of setup time. This study addresses a sequence-dependent bi-criterion scheduling problem, incorporating order delivery considerations. The primary objective is to minimize the linear combination of the makespan and the sum of weighted completion times of each order. To tackle this intricate challenge, we propose pertinent dominance rules and a lower bound, which are integral components of a branch-and-bound methodology employed to obtain an exact solution. Additionally, we introduce a heuristic approach tailored to the problem's unique characteristics, along with three refined variants designed to yield high-quality approximate solutions. Subsequently, these three refined approaches serve as seeds to generate three distinct populations or chromosomes, each independently employed in a genetic algorithm to yield a robust approximate solution. Ultimately, we meticulously assess the efficacy of each proposed algorithm through comprehensive simulation trials. [ABSTRACT FROM AUTHOR]

This study evaluates various Mixed Integer Programming (MIP) formulations for solving single-machine and parallel-machine scheduling problems, with the objective of minimizing the total completion time and the makespan of jobs. Through extensive numerical study, the MIP formulation, which is suitable for dealing with each specific single-machine or parallel-machine scheduling problem, is identified. Benchmarks are also provided for the development of other algorithms for future research.

In this paper, we study the issue of single-machine rescheduling with linear deteriorating jobs and position-based learning effects simultaneously in response to an unexpected arrival of new jobs. The scheduling efficiency is measured in terms of the makespan, while the cost of disruption is measured in terms of the maximum difference in processing orders of the original jobs before and after disruption. By introducing the effects of deterioration and learning, the job actual processing time is defined by an increasing function of its starting time, meanwhile a decreasing function of its position. Two types of problems are considered. For the first one, the makespan is minimised subject to a limit on the maximum sequence disruption; while in the second one, a linear combination of the makespan and the maximum sequence disruption is minimised. For each problem, the polynomial solvability is demonstrated, and an efficient algorithm is then developed. Finally, extensive computational experiments are conducted to show the efficiency and running behaviours of the proposed algorithms. [ABSTRACT FROM PUBLISHER]

The paper is devoted to some single-machine scheduling problems with variable job processing times. The objectives are to minimize the makespan (i.e., the maximum completion time of all jobs), and to minimize the total completion time. For some special cases, we show that these problems can be solved in polynomial time. For some another special cases of the makespan and the total completion time minimization problems, we prove that an optimal schedule has an V-shape property in terms of processing times. We also propose a heuristic algorithm by utilizing the V-shape property. [ABSTRACT FROM AUTHOR]

Scheduling with deterioration effects has been widely investigated in the past two decades. In realistic situations, the deterioration effect might accelerate, especially in the food manufacturing industry. In this paper we propose a scheduling model with an accelerating deterioration effect. We show that the single-machine problems under the model to minimize the makespan, total completion time, total weighted completion time, maximum lateness, maximum tardiness, and total tardiness remain polynomially solvable. [ABSTRACT FROM AUTHOR]

In scheduling problems with learning effects, most research assumes that processing times are deterministic. This paper studies a single-machine scheduling problem with a position-based learning effect and fuzzy processing times where the objective is to minimize the makespan. The position-based learning effect of a job is assumed to be a function of its position. The processing times are considered to be triangular fuzzy numbers. Two different polynomial-time algorithms are developed for the problem. The first solution methodology is based on the fuzzy chance-constrained programming, whereas the second is based on a method to rank fuzzy numbers. Computational experiments are then conducted in order to evaluate the performance of the algorithms. [ABSTRACT FROM AUTHOR]

This paper considers single-machine scheduling problems with group technology (GT). We consider the case of group setup times and job processing times are a decreasing function of their starting time. We first prove that the makespan minimization problem remains polynomially solvable under the general decreasing linear deterioration. We then prove that the total weighted completion time minimization problem remains polynomially solvable under the proportional decreasing linear deterioration. [ABSTRACT FROM AUTHOR]

The paper deals with the single-machine scheduling problem with a sum-of-processing-time- based learning effect and deteriorating jobs. By the effects of sum-of-processing-time-based learning and deterioration, we mean that the processing time of a job is defined by function of its starting time and total normal processing time of jobs in front of it in the sequence. It is shown that, even with the introduction of the effects of sum-of-processing-time-based learning and deterioration to job processing times, the single-machine makespan minimization problem remains polynomially solvable. [ABSTRACT FROM AUTHOR]

Machine scheduling problems with deteriorating jobs have received increasing attention in recent years, mostly focusing on the linear deterioration models. However, if certain maintenance procedures fail to be completed prior to a prespecified deadline, jobs will require extra time for successful accomplishment in some situations. Therefore, this paper addresses a single-machine problem where the objective is to minimize the makespan under the piecewise linear deterioration model. A branch-and-bound algorithm and two heuristic algorithms are provided to search for the optimal solution and near-optimal solutions, respectively. Computational results are also presented to evaluate the performance of the proposed algorithms. [ABSTRACT FROM AUTHOR]

Abstract: This paper studies the single-machine scheduling problem with the effects of deterioration and learning under group consumption, where the processing time of a job is defined by the function of the starting time and position in the group. Based on the analysis of properties and polynomial algorithms, it can be shown that both the single-machine makespan minimization problem and the total resource minimization problem under the group consumption are polynomially solvable, even though the deterioration and learning effect on job processing time is introduced. [Copyright &y& Elsevier]

Recently, deteriorating job scheduling problems have received increasing attention. However, the majority of the research assumes that the actual job processing time is a function of its starting time. In this note, we develop a new deterioration model where the actual job processing time is a function of jobs already processed. We show that the single-machine makespan problem remains polynomially solvable under the proposed model. [ABSTRACT FROM AUTHOR]

Abstract: In many situations, the skills of workers continuously improve when repeating the same or similar tasks. This phenomenon is known as the “learning effect” in the literature. In most studies, the learning phenomenon is implemented by assuming the actual job processing time is a function of its scheduled position [D. Biskup, Single-machine scheduling with learning considerations, Eur. J. Oper. Res. 115 (1999) 173–178]. Recently, a new model is proposed where the actual job processing time depends on the sum of the processing times of jobs already processed [C. Koulamas, G.J. Kyparisis, Single-machine and two-machine flowshop scheduling with general learning functions, Eur. J. Oper. Res. 178 (2007) 402–407]. In this paper, we extend their models in which the actual job processing time not only depends on its scheduled position, but also depends on the sum of the processing times of jobs already processed. We then show that the single-machine makespan and the total completion time problems remain polynomially solvable under the proposed model. In addition, we show that the total weighted completion time has a polynomial optimal solution under certain agreeable solutions. [Copyright &y& Elsevier]

In this paper, we study a single-machine scheduling problem with the cyclic process of an aging effect. This phenomenon appears in many realistic production processes. Thus, it is important to consider the phenomenon in scheduling problems. We analyse the single-machine makespan scheduling problem with two different aging effect models and provide a polynomial time algorithm to solve the problem. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the single-machine makespan scheduling problem with start-time dependent processing time. The objectives are to minimize the makespan and to minimize the sum of the th powers of completion times. We prove that several cases are polynomially solvable under some restrictions of the parameters. In addition, these cases still remain polynomially solvable when the restriction of a certain parameter is relaxed from a positive integer to a real number. [Copyright &y& Elsevier]