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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.

Various staff methodologies of a just‐in‐time (JIT) apparel assembly cell with various numbers of walking workers, and various levels of process time variation were discussed and evaluated by simulation models. Decouplers are placed between two workstations (or subcells) to improve capability and flexibility in an apparel cell. Decouplers enable JIT pull cells to operate with minimum stock‐on‐hand and allow parts and information to flow in opposite directions. Decouplers also provide the JIT pull cell with “make one, check one, and pass one on” capability. A manned assembly cell’s throughput rate depends on the number of workers in the cell and on the variation in each worker’s processing time. Normally, as the processing time variation increases, the throughput rate decreases. However, these simulation studies show that doubling the decoupler capacity increases the cell’s output, even as the processing time variation increases.

The purpose of this paper is to use lean principles and simulation optimization on solving a combined hospital emergency department (ED) layout design and staff assignment problem.

This study is based on value stream mapping for the design and analysis of the ED. Subsequently, the authors investigate cellular manufacturing design, which addresses the decisions of continuous steps in a cell simultaneously and considers the optimal staff assignment. A simulation based on the case study is used for these methodologies. Simulation optimization is then used to optimize the staff assignments, minimize the waiting time and maximize the service level.

The linear layout outperformed in both waiting time and service level. The patients’ average waiting time is reduced from 78 to 38 minutes. The service level increased from 54.86 to 88.55 percent. Moreover, the number of nurses was reduced from nine to six.

First, the tests for model accuracy were performed using the actual arrival rate; however, seasonal variation should be reflected. Second, the staffing levels varied were not tracked. Third, the accuracy of individual patient treatment paths can be dynamic. Fourth, the 25 percent of delays in transferring a patient to an inpatient bed will be discussed in future studies.

A practical case is adopted for empirical illustrations.

The proposed methodology innovatively solved a practical application and the results are promising.

This study aims to examine the impact of lean manufacturing (LM) on the financial performance of companies affected by emergency situations. It additionally explores the role of advanced manufacturing technologies (AMTs) in complementing LM to enhance financial performance in emergency and non-emergency situations.

Both survey and archival data were collected from 219 manufacturing companies in China. With longitudinal data collected before and after an emergency situation (i.e. Typhoon Rumbia), regression analysis was conducted to investigate the effects of LM and AMTs on financial performance in different contexts.

Our results reveal an inverted U-shaped relationship between LM and financial performance in the context of emergency. We also found that AMTs exerted a positive moderation effect on the inverted U-shaped relationship, indicating high levels of AMTs that mitigated the inefficiency of LM in coping with supply chain emergencies.

Through simultaneous investigation of LM and AMTs as bundles of practices and their fit with different contexts, this study takes a systems approach to fit that advances the application of contingency theory in the Operations Management literature to more complex patterns of fit.

This study illuminates how AMTs support LM practices in facilitating organizational performance in different contexts. Specifically, this study unravels the interaction mechanisms between AMTs and LM in influencing financial performance in emergency and non-emergency situations.

Prior studies have confirmed market segmentation as an important shackle to China's macroeconomy upgrade, but the systematic analysis of microenterprise upgrade remains inadequate. This paper aims to investigate the nonlinear impact of market segmentation on microenterprise upgrade.

The price method was applied to calculate China's provincial market segmentation, including commodity, capital, labor and energy. The generalized method of moments was employed to examine the nonlinear impact of market segmentation on the upgrading of manufacturing enterprises based on microenterprise data from 2003 to 2019.

First, China’s heterogeneous market segmentations have been significantly reduced. Macroeconomics and policies are critical factors in market integration. Second, there is an inverted U-shaped relationship between China’s total market segmentation and the upgrading of manufacturing enterprises. Third, the relationship between the commodity market segmentation, labor market segmentation, energy market segmentation and manufacturing enterprises' upgrade is shown as an inverted U-shaped. Nevertheless, the relationship between the capital market segmentation and upgrading of manufacturing enterprises exhibits a U-shape.

The impact of market segmentation on the upgrading of manufacturing enterprises in China performs nonlinearly. An inverted U-shaped relationship exists between market segmentation in commodity, labor and energy and the upgrading of manufacturing enterprises, while a U-shaped relationship prevails between capital market segmentation and the upgrading of manufacturing enterprises.

The purpose of this paper is to examine how households’ engagement in concurrent business (CB), which is measured by the contribution of off-farm income to household income, affects the farm size–technical efficiency (TE) relationship in Northern China.

This paper applies a stochastic frontier analysis method to analyze data on 1,006 rural households collected from four major wheat-producing provinces in Northern China, adopting a translog specification for the underlying production function.

The analysis yields three findings. First, the farm size–TE relationship is inverted U-shaped for all CB engagement levels higher than 5 percent, and the most technically efficient farm size increases with the level of household CB engagement. Second, how TE varies with the level of CB engagement depends on farm size: an inverted-U relationship for relatively small farms (<10μ), a positive relationship for middle-size farms (10–20μ), and a negative relationship for large farms (>20μ). Finally, the overall TE score, 0.88, suggests that wheat output can be increased by 12 percent in Northern China if technical inefficiency were eliminated.

Unlike most previous studies that examine the impacts of farm size and households’ off-farm business involvement separately, this paper examines how these two factors interact with each other.

Describes the application of the Group Technology concept in scheduling industrial bag production in a woven products division of a bag manufacturer. The labour assignments, determined through a linear goal programming model, minimize unbalanced workloads among the operations. This study shows a new application area of the Group Technology concept which leads to a better solution of labour assignments and provides management with valuable information essential to the development of a strategic competitive advantage.

There are both “Swedish” and “Japanese” models for the organization of final assembly. Discusses the theoretical and historical background to these models and the main practical differences between them. Provides an empirical study based on action research conducted in the final assembly area of a Scottish electronics company. The aims of the research were to effect change in the company by applying just‐in‐time (JIT) assembly methods, and to observe the process of change and the consequences for production of the cellular approach to assembly and the formation of assembly teams. Two projects were undertaken. In the first, a JIT cell was built for the assembly of a new product; this cell and an existing, conventional flowline operated in parallel for a period. In the second, a work team was formed, consisting of the operators assembling an older product on a machine‐paced line; the members of this team were given a significantly higher level of work autonomy than before. Provides a detailed account of the two projects.

There is widespread interest and discussion of Just‐in‐Time (JIT) manufacturing but little is known about the actual uptake and pattern of use of JIT and its constituent techniques. This article reports the results of a survey of UK manufacturing companies. The survey examined the level of consideration of JIT in the UK, the nature of the JIT effort, the JIT techniques used and not used, the effectiveness of the various techniques and the benefits reported from JIT. The data are reviewed by industry, sector, size and parent company and conclusions are developed concerning the nature of the application of JIT in the UK. The data indicate that though the overall level of interest in JIT is high, there are a number of causes for concern in the way in which it is being implemented.

Rabbit chase (RC) is used as one of the most effective techniques in manufacturing systems, as such systems have high level of adaptability and increased productivity in addition to providing uniform workload balancing and skill improving environment. In assembly systems, RC inspires the development of walking worker assembly line (WWAL). On the other hand, U-type assembly lines (UALs) may provide higher worker utilization, lower space requirement and more convenient internal logistics when compared to straight assembly lines. In this context, this study aims to improve assembly line performance by generating RC cycles on WWAL with respect to task assignment characteristics of UAL within reasonable walking distance and space requirement. Therefore, a novel line configuration, namely, segmented rabbit chase-oriented U-type assembly line (SRCUAL), emerges.

The mathematical programming approach treats SRCUAL balancing problem in a hierarchical manner to decrease computational burden. Firstly, segments are generated via the first linear programming model in the solution approach for balancing SRCUALs to minimize total number of workers. Then, stations are determined within each segment for forward and backward sections separately using two different pre-emptive goal programming models. Moreover, three heuristics are developed to provide solution quality with computational efficiency.

The proposed mathematical programming approach is applied to the light-emitting diode (LED) luminaire assembly section of a manufacturing company. The adaptation of SRCUAL decreased the number of workers by 15.4% and the space requirement by 17.7% for LED luminaire assembly system when compared to UAL. Moreover, satisfactory results for the proposed heuristics were obtained in terms of deviation from lower bound, especially for SRCUAL heuristics I and II. Moreover, the results indicate that the integration of RC not only decreased the number of workers in 40.28% (29 instances) of test problems in U-lines, but also yielded less number of buffer points (48.48%) with lower workload deviation (75%) among workers in terms of coefficient of variation.

This study provides convenience for capacity management (assessing capacity and adjusting capacity by changing the number of workers) for industrial SRCUAL applications. Meanwhile, SRCUAL applications give the opportunity to increase the capacity for a product or transfer the saved capacity to the assembly of other products. As it is possible to provide one-piece flow with equal workloads via walking workers, SRCUAL has the potential for quick realization of defects and better lead time performance.

To the best of the authors’ knowledge, forward–backward task assignments in U-type lines have not been adapted to WWALs. Moreover, as workers travel overall the line in WWALs, walking time increases drastically. Addressing this research gap and limitation, the main innovative aspect of this study can be considered as the proposal of a new line design (i.e. SRCUAL) which is sourced from the hybridization of UALs and WWAL as well as the segmentation of the line with RC cycles. The superiority of SRCUAL over WWAL and UAL was also discussed. Moreover, operating systematic for SRCUAL was devised. As for methodical aspect, this study is the first attempt to solve the balancing problem for SRCUAL design.