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The paper formulates a bi-objective mixed-integer nonlinear programming model, aimed at minimizing the total labor hours and the workload unfairness for the multi-skilled worker assignment problem in Seru production system (SPS).

Three approaches, namely epsilon-constraint method, non-dominated sorting genetic algorithm 2 (NSGA-II) and improved strength Pareto evolutionary algorithm (SPEA2), are designed for solving the problem.

Numerous experiments are performed to assess the applicability of the proposed model and evaluate the performance of algorithms. The merged Pareto-fronts obtained from both NSGA-II and SPEA2 were proposed as final solutions to provide useful information for decision-makers.

SPS has the flexibility to respond to the changing demand for small amount production of multiple varieties products. Assigning cross-trained workers to obtain flexibility has emerged as a major concern for the implementation of SPS. Most enterprises focus solely on measures of production efficiency, such as minimizing the total throughput time. Solutions based on optimizing efficiency measures alone can be unacceptable by workers who have high proficiency levels when they are achieved at the expense of the workers taking more workload. Therefore, study the tradeoff between production efficiency and fairness in the multi-skilled worker assignment problem is very important for SPS.

The study investigates a new mixed-integer programming model to optimize worker-to-seru assignment, batch-to-seru assignment and task-to-worker assignment in SPS. In order to solve the proposed problem, three problem-specific solution approaches are proposed.

Agency work represents a unique form of employment that has received increased attention in recent years. Supporters of the agency employment industry have cited increased accessibility and flexibility at an individual and organisational level, yet critics have highlighted disparities in treatment and the limited protection afforded by the contract. Previous psychological studies into the working experiences of these employees have forwarded a series of findings that have frequently conflicted, so this paper begins by exploring research into the areas of motive, job satisfaction, job security, and organisational support. The purpose of this paper is to better understand how this form of employment can psychologically affect agency workers by focusing upon these key areas.

The study's research design incorporated 25 semi-structured interviews with agency workers, recruitment consultants, and representatives from third-party employers. These interviews were then supplemented by longitudinal data from follow-up interviews conducted with agency workers from the initial sample. During the study, the researcher undertook a number of agency working assignments, and ethnographic analysis of diary extracts represented a third source of data.

Results highlighted the importance of motive, as it was found to influence how agency workers viewed their employment. The lack of obligation in temporary contracts was perceived to lead to isolation from permanent colleagues, increase vulnerability, and reduce job security and organisational commitment.

Findings strongly supported the claim that the pre-assignment motives of individuals had a significant impact upon their resulting experiences. Agency workers employed in longer-term assignments reported greater integration into the organisation, resulting in increased commitment towards the third-party employer, and improved relationships with permanent staff.

The current research incorporated multiple perspectives to create an increased understanding of the agency employment industry and its impact upon individuals.

The purpose of this paper is to construct a task assignment model for U-shaped production lines with collaborative task, which is optimized by minimizing the number of workers and balancing the workload of the operators. The ultimate goal is to increase productivity by increasing the U-line balance and balancing the load on the operators.

First, task selection and update mechanism are analyzed and the task selection mechanism suitable for collaborative task is proposed. Second, M-COMOSAL is obtained by improving the original COMOSAL. Finally, The M-COMOSAL algorithm and the COMAOSAL algorithm are used to perform job assignment on the double-acting clutch U-shaped assembly line.

According to the allocation scheme obtained by M-COMSOAL, the beat can be adjusted according to the change of order demand. The final allocation scheme is superior to the COMSOAL algorithm in terms of number of workers, working time, production tempo and balance rate. In particular, compared with the old scheme, the new scheme showed a decrease of 16.7% in the number of employees and a 18.8% increase in the production line balance rate. Thus, the method is helpful to reduce the number of operators and balance the workload.

The new algorithm proposed in this paper for the assignment of collaborative task can minimize the number of workers and balance the load of operators, which is of great significance for improving the balance rate of U-shaped production lines and the utilization of personnel or equipment.

The purpose of this paper is to investigate the multi-skilled workers assignment problem in complex assembly systems such as aircraft assembly lines. An adaptive binary particle swarm optimization (A-BPSO) algorithm is proposed, which is used to balance the workload of both assembly stations and processes and to minimize the human cost.

Firstly, a cycle time model considering the cooperation of multi-skilled workers is constructed. This model provides a quantitative description of the relationship between the cycle time and multi-skilled workers by means of revising the standard learning curve with the “Partition-And-Accumulate” method. Then, to improve the accuracy and stability of the current heuristic algorithms, an A-BPSO algorithm that suits for the discrete optimization problems is proposed to assign multi-skilled workers to assembly stations and processes based on modified sigmoid limiting function.

The proposed method has been successfully applied to a practical case, and the result justifies its advantage as well as adaptability to both theory and engineering application.

A novel cycle time model considering cooperation of multi-skilled workers is constructed so that the calculation results of cycle time are more accurate and closer to reality. An A-BPSO algorithm is proposed to improve the stability and convergence in dealing with the problems with higher dimensional search space. This research can be used by the project managers and dispatchers on assembly field.

The paper is concerned with dynamic job assignment when observed performance is an imperfect signal of the worker's type. When the rate of learning from past performance depends upon the particular job performed, promotion can be due to good performance only at a job for which the resulting probability of mistaking a low‐ability type for a high‐ability type is higher than for the job the worker is upgraded to. Income risk can be greater for old workers than for young workers. The length of the worker's active life is relevant for job mobility notwithstanding optimal myopic procedures for job assignment. The dynamic perspective induced by learning can generate new forms of opportunism.

Research shows that the risk of work-related disorders is higher among temporary agency workers than among other employees. The purpose of this paper is to describe the working conditions of temporary agency workers and explains which factors contribute towards work-related disorders for this group.

This paper is based on a survey responded to by 482 agency workers in Sweden. The dependent variable is the prevalence of work-related disorders. Independent variables include personal characteristics, job characteristics, employment characteristics and temporary agency work characteristics.

The study indicates several risk factors: holding a position as a blue-collar worker; being assigned to more physically demanding work tasks and having fewer opportunities to learn new things than client organization employees; lacking training for work tasks; and lacking clarity regarding which work tasks to do during an assignment.

The theoretical implications of this study are related to the dual employment-management relationship in temporary agency work where the temporary work agency and client organization follow different logics. The logic in the employment relationship is to contract temporary agency workers out to client organizations, thus there is no time for formal training. The logic in the management relationship lies in making temporary agency workers profitable as soon as possible, encouraging shortcuts in training and instruction; thus, temporary agency workers risk being left with a lack of clarity regarding what to do and how to do it.

This chapter studies the negative signals associated with nonpromotion. I first show theoretically that, when workers' productivity rises little with additional years on the same job level, the negative signal associated with nonpromotion leads to wage decreases. On the other hand, when additional job-level tenure leads to a sizable increase in productivity, workers' wages increase. I then test my model's predictions using the personnel records from a large US firm from 1970–1988. I find a clear hump-shaped wage-job-tenure profile for workers who stay at the same job level, which supports my model's prediction.

This chapter presents application of multi-criteria mathematical programming models by integer and mixed-integer programming for optimal allocation of workers among supporting services in a hospital. The services include logistics, inventory management, financial management, operations management, medical analysis, etc. The optimality criteria of the problem are minimization of operational costs of supporting services subject to some specific constraints. The constraints represent specific conditions for resource allocation in a hospital. The overall problems are formulated as assignment models, where the decision variables represent the assignment of people to various jobs. Numerical examples are presented. Some computational results modeled on a real data from a hospital in Poland are reported.

The purpose of this paper is to present the process of balancing a mixed-model assembly line by incorporating unskilled temporary workers who enhance productivity. The authors develop three models to minimize the sum of the workstation costs and the labor costs of skilled and unskilled temporary workers, cycle time and potential work overloads.

This paper deals with the problem of designing an integrated mixed-model assembly line with the assignment of skilled and unskilled temporary workers. Three mathematical models are developed using integer linear programming and mixed integer linear programming. In addition, a hybrid genetic algorithm that minimizes total operation costs is developed.

Computational experiments demonstrate the superiority of the hybrid genetic algorithm over the mathematical model and reveal managerial insights. The experiments show the trade-off between the labor costs of unskilled temporary workers and the operation costs of workstations.

The developed models are based on practical features of a real-world problem, including simultaneous assignments of workers and precedence restrictions for tasks. Special genetic operators and heuristic algorithms are used to ensure the feasibility of solutions and make the hybrid genetic algorithm efficient. Through a case study, the authors demonstrated the validity of employing unskilled temporary workers in an assembly line.