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Line–cell conversion and rotation of operators between cells are common in lean production systems. Thus, the purpose of this study is to provide an integrated look at these two practices through integrating job rotation scheduling and line-cell conversion problems, as well as investigating the effect of rotation frequency on flow time of a Seru system.

First, a nonlinear integer programming model of job rotation scheduling problem and line–cell conversion problem (Seru-JRSP) was presented. Then, because Seru-JRSP is NP-hard, an efficient and effective invasive weed optimization (IWO) algorithm was developed. Exploration process of IWO was enhanced by enforcing two shake mechanisms.

Computations of various sample problems showed shorter flow time and less number of assigned operators in a Seru system scheduled through job rotation. Also, nonlinear behavior of flow time versus number of rotation periods was shown. It was demonstrated that, setting number of rotation frequency to one in line with the literature leads to inferior flow time. In addition, ability of developed algorithm to generate clusters of equivalent solutions in terms of flow time was shown.

In this research, integration of job rotation scheduling and line–cell conversion problems was introduced, considering lack of an integrated look at these two practices in the literature. In addition, a new improved IWO equipped with shake enforcement was introduced.

With hybrid simulation techniques getting popular for systems improvement in multiple fields, this study aims to provide insight on the use of hybrid simulation to assess the effect of lean manufacturing (LM) techniques on manufacturing facilities and the transition of a mass production (MP) facility to incorporating LM techniques.

In this paper, the authors apply a hybrid simulation approach to improve an educational automotive assembly line and provide guidelines for implementing different LM techniques. Specifically, the authors describe the design, development, verification and validation of a hybrid discrete-event and agent-based simulation model of a LEGO® car assembly line to analyze, improve and assess the system’s performance. The simulation approach examines the base model (MP) and an alternative scenario (just-in-time [JIT] with Heijunka).

The hybrid simulation approach effectively models the facility. The alternative simulation scenario (implementing JIT and Heijunka LM techniques) improved all examined performance metrics. In more detail, the system’s lead time was reduced by 47.37%, the throughput increased by 5.99% and the work-in-progress for workstations decreased by up to 56.73%.

This novel hybrid simulation approach provides insight and can be potentially extrapolated to model other manufacturing facilities and evaluate transition scenarios from MP to LM.

The purpose of this paper is to examine firms’ knowledge-sourcing behavior in green technology development with respect to the home country’s market- vs nonmarket environmental policy stringency.

This paper empirically analyzes the effects of market and nonmarket environmental policy stringency on firms’ knowledge sourcing activity with patent data from OECD countries during 1991–2010, across five categories of green technologies.

When a nation establishes more stringent market environmental policies, firms likely source more international knowledge rather than domestic knowledge about green technology, up to a point. After that level, this balance shifts (inverted U-shaped curve) due to the risks associated with greater investment costs and commerciality. Nonmarket environmental policies instead should exhibit a positive, linear relationship with international relative to domestic knowledge sourcing. This study also reveals the dynamic roles of a firm’s green technological capability with market-based environmental policy stringency and a substitutive role of the capability with nonmarket-based environmental policy stringency.

This study shows the effect of market and nonmarket environmental policy stringency on firms’ knowledge sourcing. The findings provide meaningful implications for policymakers regarding the optimal levels of market and nonmarket environmental policy stringency that will enhance their countries’ green technology development.

This paper enriches the literature of environmental policy and knowledge sourcing and offers the direction of future research of how environmental policy stringency influences a firm’s knowledge sourcing for green technology development.

The purpose of this paper is to re‐examine the solution methodology to the facility grouping problem in group technology originally outlined by Mukhopadhyay et al. The aim of this re‐examination is to attempt to resolve some of the problems associated with the original solution methodology and to provide the system designer with an improved technique for the creation of an efficient initial system design solution. Cellular manufacture by its very nature requires work‐part transfer both within a machine cell and in some instances between machine cells. By utilising a design methodology which seeks to minimise work‐part transfer, these non‐value but cost adding tasks are kept to a minimum, thereby providing a faster throughput time and lower operational costs for companies who use cellular manufacturing systems in their production operations.

In approach, the technique advocated parallels the possible alternative solution method suggested by John et al. to resolve the problem of edge ranking ties which exists in the original Mukhopadhyay et al. solution technique. Presented and discussed in this contribution is a revised flow direction weighting scheme (FDWS) which simplifies the solution input data requirements and overcomes a perceived disadvantage in the earlier scheme outlined by John et al. The methodology outlined in the paper is subsequently evaluated for its generic nature, applicability and effectiveness via the use of previously published synthetic production data, and the findings compared to the results determined by several alternative approaches to the problem.

The development and application of the FDWS to cellular manufacturing system design is outlined in the paper and the usefulness of the technique is subsequently examined and compared to the results found for several competing methods. The approach provides for the identification of improved solutions to the test problems examined in both of the earlier contributions by Mukhopadhyay et al., and John et al. In addition, the results show that irrespective of the assessment criteria used, the FDWS technique provides solutions that are comparable to or better than the alternative approaches examined.

The proposed FDWS technique further contributes to the existing knowledge base on cellular manufacturing system design. It can provide good initial solution guidance for manufacturing system designers and thereby reduce the time required to achieve an acceptable and cost efficient design for a cellular production system.

Aims to detail the ongoing implementation of lean manufacturing at a UK‐based electronic product‐manufacturing operation.

Describes how and why a manufacturing operation, which had already seen major improvements that had made it a highly regarded plant, is adopting lean manufacturing as part of a manufacturing survival strategy. It also looks at some of the main Lean projects undertaken, the major benefits gained and the key lesson learned.

While the operation's highly effective continuous improvement programme had delivered a major culture change along with significant OEE and quality improvements, the introduction of lean manufacturing highlighted that this had been achieved at the cost of creating a number of “islands of excellence”; resulting in high levels of WIP and long lead times. The implementation of lean manufacturing is now enabling this electronic products manufacturer to build on its excellent foundation of continuous improvement, and start the process of moving away from batch and queue to creating flow through the whole plant; reducing WIP and lead time, and improving productivity, without compromising previous gains.

Brings to the attention of managers how it often takes the wider focus offered by lean manufacturing to discover the hidden waste that can reside even in operations that appear to be very effective. Confirms the importance of moving from a batch and queue mentality to process flow, and the productivity benefits that can be gained, but also highlights that even well‐organised businesses are liable to suffer pain when implementing lean, especially with respect to introducing flow and eliminating WIP, which has to be worked through.

This paper aims to evaluate two operational modes of the worker allocation problem (WAP) in the multiple U-line system (MULS). Five objectives are optimised simultaneously for the most complicated operational modes, i.e. machine-dominant working and fixed-station walking. Besides, the benefits of using multiline workstations (MLWs) are investigated.

The elite non-dominated sorting differential evolutionary III (ENSDE III) algorithm is developed as a solution technique. Also, the largest remaining available time heuristic is proposed as a baseline in determining the number and utilisation of workers when the use of MLWs is not allowed.

ENSDE III outperforms the cutting-edged multi-objective evolutionary algorithms, i.e. multi-objective evolutionary algorithm based on decomposition and non-dominated sorting differential evolutionary III, under two key Pareto metrics, i.e. generational distance and inverted generational distance, regardless of the problem size. The best-found number of workers from ENSDE III is substantially lower than the upper bound. The MULS with MLWs requires fewer workers than the one without.

Although this research has extended several issues in the basic model of multiple U-line systems, some assumptions were used to facilitate mathematical computation as follows. The U-line system in this research assumed that all lines were produced only a single product. Besides, all workers were well-trained to gain the same skill. These assumptions could be extended in the future.

The implication of this research is the benefits of multiline workstations (MLWs) used in the multiple U-line system. Instead of leaving each individual line to operate independently, all lines should be working in parallel through the use of MLWs to gain benefits in terms of worker reduction, balancing worker’s workload, higher system utilisation.

This research is the first to address the WAP in the MULS with machine-dominant working and fixed-station walking modes. Worker’s fatigue due to standing and walking while working is incorporated into the model. The novel ENSDE III algorithm is developed to optimise the multi-objective WAP in a Pareto sense. The benefits of exploiting MLWs are also illustrated.

Seru (cell) manufacturing system has achieved huge success in production. However, related research is limited, especially, the problem of cross-trained worker assignment. The purpose of this paper is to solve this problem for two representative seru types, divisional and rotating seru, and subsequently, compare throughput performance between the two seru types under reasonable worker-task assignment.

For the cross-trained worker assignment problem, this research presents new models aiming at maximum throughput of seru and workload balance of workers under considering skill levels (SLs) and several practical constraints. Furthermore, factorial experiments that involve four factors, the number of tasks (NT), gap of task time, SL and gap of SL, are performed to compare throughput performance between divisional and rotating seru.

First, the maximum throughput of the divisional seru is better than that of the rotating seru under suitable worker assignment. Second, in the seru which has less difference of task time, throughput performance of the rotating seru is better than the divisional seru when the NT is close to the number of assigned workers. Moreover, the influence tendency of the four factors on throughput gap between the two seru types is significant.

This research addresses the worker-task assignment for divisional and rotating seru based on their characteristics. Several findings can help decision maker select more applicable seru type according to various production environments from the perspective of optimum throughput.

This article examines the impact of introducing computer technology in just‐in‐time (JIT) systems. Literature review has generally supported the notion that introducing computers within JIT production systems may enhance productivity. Also, the productivity of a computer integrated manufacturing (CIM) system may be enhanced by integrating it with the just‐in‐time (JIT) production system. This integrated production system is called the computer integrated just‐in‐time (CIJIT) production system. This empirical study provides strong evidence that integration of CIM and JIT can significantly improve a firm′s productivity and competitiveness.

The purpose of this paper is to highlight the lessons learned from two kaizen events for productivity improvement in a printing company. The paper suggests how to organize lean tools to improve productivity through the use of organized kaizen events in the printing industry to meet defined targets.

This paper is based on a field study involving participant observations. The relationships among the three specific tools, line balancing, standardized work and standardized layout that are used in a kaizen event of a printing factory, are examined.

Application of a mix of lean tools resulted in significant productivity improvements of 10-30 percent in the assembly area of the printing company. Based on the outcomes of the lean tools that are applied in various work areas, the best combinations of lean tools are identified and several key considerations are discussed.

This paper shows that a combined set of lean tools such as line balancing, standardized work and standardized layout can be applied to improve productivity in the printing operations, which is identifiable with a mix of processes that are both labor intensive and equipment flexible.

The paper fills the literature gap on the use of specific lean tools: line balancing, standardized work and standardized layout in the printing industry. The findings from this research can be applied to other assembly systems that are similar to the printing industry.

Cellular manufacturing is the organisation of manufacturing equipment based on the requirements of the product or component. Transition to cellular manufacturing generally requires reorganisation of existing equipment. It is likely that the existing equipment alone is not suitable for a cellular layout. During the cell planning and design phase equipment investment analysis is important to identify equipment needs. Transition from job shop production to cellular production is detailed. Cell formation and cell evaluation techniques are provided to assist in equipment procurement decisions. In particular, a structured procedure and analytical tools are given to evaluate fully the cellular system to identify appropriate equipment and methods. A case example is provided to explain the procedure.