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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.

Design, balancing, and sequencing are the key issues associated with assembly lines (ALs). The purpose of this paper is to identify AL design issues and to develop an integrated methodology for mixed‐model assembly line balancing (MMALB) and sequencing. Primarily, mixed‐model lines are utilized for high‐variety, low‐volume job shop or batch production. Variation of a generic product is important for the manufacturers as the demand is mostly customer driven in the present global market.

Different AL design norms, performance indexes, and AL workstation indexes have been identified in the initial stage of this work. As the paper progresses, it has focused towards an integrated approach for MMALB and sequencing addressed for small‐ and medium‐scale assembly plants. A small‐scale practical problem has been justified with this integrated methodology implemented by MATLAB.

ALs execution in the production floor require many important factors to be considered. Different line orientations, production approaches, line characteristics, performance and workstation indexes, problem definitions, balancing and product sequencing in accordance with the objective functions are needed to be taken into account by the line designer.

This paper has highlighted the important AL design characteristics and also provided an integrated approach for balancing mixed‐model assembly lines (MMALs) combined with sequencing heuristic. The findings of this paper can be helpful for the designers while designing an AL. The integrated approach for balancing and sequencing of MMALs can be used as a functional tool for assembly‐based contemporary industries.

This second part of the paper presents in more detail the phylogenetic model of automotive assembly factories used in the first part of the paper. The key organizational species and their mutual relationships are described with an emphasis on the speciation points. This paper is purely descriptive.

An interpretative chart is proposed on several levels, which on the one hand acts as a key to the actions aimed at revision of simultaneous design criteria, and on the other is a methodological indication of how to articulate simultaneous actions on the product and the process. For each level the action levers and objectives are further described in an attempt to distinguish both single and multiple lever‐objective relationships. Finally, ways of carrying out simultaneous actions on the product and the process, together with the problems involved are discussed.

This paper aims to study a generalized type of mixed-model assembly line with multi-manned workstations where multiple workers simultaneously perform different tasks on the same product. This special kind of assembly line is usually utilized to assemble different models of large products, such as buses and trucks, on the same production line.

To solve the mixed-model multi-manned assembly line balancing problem optimally, a new mixed-integer-programming (MIP) model is presented. The proposed MIP model is nondeterministic polynomial-time (NP)-hard, and as a result, a simulated annealing (SA) algorithm is developed to find the optimal or near-optimal solution in a small amount of computation time.

The performance of the proposed algorithm is examined for several test problems in terms of solution quality and running time. The experimental results show that the proposed algorithm has a satisfactory performance from computational time efficiency and solution accuracy.

This research is the very first study that minimizes the number of workers and workstations simultaneously, with a higher priority set for the number of workers, in a mixed-model multi-manned assembly line setting using a novel MIP model and an SA algorithm.

Many manufacturers have attempted to improve the productivity of their facilities without much success. The Japanese, on the other hand, have recently achieved significant improvements in productivity by implementing JIT. There are several reasons for the Japanese success. First, JIT adheres to well‐established concepts and methods of production and operations management. Second, JIT is a holistic approach to productivity that directs attention to all resources involved in producing a product, and to all factors affecting their utilization. Third, JIT avoids many obstacles to productivity, in addition to utilizing resources efficiently. Fourth, JIT focuses on shopfloor design and operations where resources are primarily affected. Manufacturing managers can learn several useful lessons for improving productivity from the Japanese experience.

Comparisons of western manufacturing management with Japanese methods have highlighted a number of differences between them. But a comparison of earlier western ideas about manufacturing shows remarkable similarities between the two. Henry Ford′s ideas and practices show many features seen in contemporary Japanese approaches. Ford, in the period from 1908 through the late 1920s, relied on a number of progressive and radical methods in manufacturing management; methods that were similar to the current Japanese methods.

This study aims to investigate how to identify and address production levelling problems in assembly lines utilising an intensive manual workforce when higher productivity levels are urgently requested to meet market demands.

A mixed-methods approach was used in the research design, integrating case study analysis, interviews and qualitative/quantitative data collection and analysis. The methodology implemented also introduces to the literature on operational performance a novel combination of data analysis methods by introducing the use of the Natural Language Understanding (NLU) methods.

First, the findings unveil the impacts on operational performance that transportation, limited documentation and waiting times play in assembly lines composed of an intensive workforce. Second, the paper unveils the understanding of the role that a limited understanding of how the assembly line functions play in productivity. Finally, the authors provide actionable insights into the levelling problems in manual assembly lines.

This research supports industries operating assembly lines with intensive utilisation of manual workforce to improve operational performance. The paper also proposed a novel conceptual model prescriptively guiding quick and long-term improvements in intensive manual workforce assembly lines. The article assists industrial decision-makers with subsequent turnaround strategies to ensure higher efficiency levels requested by the market.

The paper offers actionable findings relevant to other manual assembly lines utilising an intensive workforce looking to improve operational performance. Some of the methods and strategies examined in this study to improve productivity require minimal capital investments. Lastly, the study contributes to the empirical literature by identifying production levelling problems in a real context.

The just‐in‐time (JIT) production system is notable for its emphasis on employee involvement and participation. However, we suggest that the role of participation that is most typically described in the organizational behavior (OB) literature does not match the type of participation practiced in JIT. We introduce a theoretical framework that accounts for these different perspectives: whereas the OB approach treats participation as an intervention and hence as an independent variable, the JIT approach sees it as a side effect of the JIT production system and hence a dependent variable. Understanding of the differences is essential in JIT implementation in the workplace if we are to avoid miscommunication, stress, and disbelief in the system.

Today's market environment is characterized by an increasing demand for greater product variety. This has inevitably led to decreased product life cycle and forced volume manufacturers to consider switching from the mass production of a limited range of products to lower volume production of a wider range. This trend is observable in moves towards lean production within the car industry.