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The main operations of the powder-coating process are staggered along a closed-loop conveyor. Given the volatile market demands, using a fixed level of staffing may result in significant productivity losses. The present study aims to capture stochastic behavior and optimize operator assignment problems in a practical powder-coating process. By using the proposed methodology, when demand changes, the optimal operator assignment configuration can be provided, ensuring high labor productivity.

The powder-coating process is an important industrial application and is often a labor-intensive system. The present study adopts a practical case to optimize its staffing level. Because of its operational complexity, the problem is solved by a proposed simulation-optimization approach. The results are promising, and the proposed methodology is shown to be an effective approach.

The proposed methodology was tested for various demand levels. The optimized operator assignment configuration always improves on the performance of other staffing levels. Given the same daily throughput, the optimized operator assignment configuration can improve performance by as much as 19%. In scenarios where there is increased demand, the resulting reduction in overtime work improves performance by between 20.33% and 56.72%. In scenarios where there is reduced demand, the optimized staffing level produces improvements between 3.13% and 50%. Compared with the fixed staffing policy of the case company, the flexible staffing policy of the proposed methodology can maintain high labor productivity across demand variations. The results are consistent with the Shojinka philosophy of the Toyota Production System.

This study proposes a solution to the operator assignment decision in a labor-intensive manufacturing system – a powder-coating processing system. Powder coating provides a solid powder coating without any solvent. Because of its excellent application performance and environmental protection, it is widely used in the field of metal coating, especially appliances for offices and homes. Most of the existing literature has solved the problem by making unrealistic assumptions. The present study proposes a simulation-optimization method to solve a practical problem in powder-coating processing. The effectiveness of the proposed methodology is illustrated by a practical application. According to the experimental results, five operators can be saved for the same daily throughput. An average of 35 and 19 min of overtimes can be saved when demand increases by 10% and 20% with one less operator; between 2 and 16 operators can be saved when demand falls by 10%–60%.

The purpose of this paper is to analyze abnormal behavior patterns in a maintenance outsourcing process. Based on the results, the managers can focus on the abnormal behavior and the direction of the investigation can be narrowed. The abnormal behavior can be identified more easily.

Maholanobis Distance (MD) and Decision Tree (DT) are integrated to analyze for abnormal behavior patterns. To prevent abnormal behaviors, a maintenance outsourcing case must be passed by several managers in different departments. In this research, some criteria for pairs of managers are calculated first. Based on the criteria, the MDs of these pairs can be calculated. Pairs are categorized by their MDs. Any pair whose MD is higher than a threshold is labeled “abnormal” while the remaining are labeled “normal”. After oversampling the minority class of abnormal, a DT is built by Classification and Regression Trees (CART) based on the labeled dataset. Finally, the combination of criteria for abnormal categories is extracted from the tree.

Through the results from the DT, the combinations of criteria provide obvious characteristics of cases that are categorized as abnormal, and then provide a direction for investigators. Thus, the range of investigation can be narrowed. The empirical results show that the result of the proposed integrated methodology is helpful for abnormal behavior pattern analysis.

This research is intended to help an organization to enhance their investigation in a large number of maintenance outsourcing cases. About 8,000 cases are collected for analysis.

The integration of MD and DT for analyzing abnormal behavior patterns in a maintenance outsourcing process is not found in the literature. Moreover, the empirical results show that the proposed integrated methodology is helpful in a real application.

In recent years, people have started to realize the importance of environmental protection, and in particular the problem of global warming. Consequently, many governments have started to view decreasing carbon emissions as a priority. Green transportation is one of the policies that is relevant to these efforts. This research aims to optimize the routing plan with minimizing fuel consumption.

In this research, a model is proposed for calculating the total fuel consumption when given a routing plan. Three factors which greatly affect fuel consumption of transportation – transportation distance, transportation speed and loading weight – are taken into consideration. Then a simple Tabu Search is used to optimize the routing plan and an experimental evaluation of the proposed method is performed.

It is shown that the proposed method provides substantial improvements over a method based on minimizing transportation distances.

The experimental results show that the routing plans found by the proposed method require less fuel consumption than that found by optimizing methods in which the distance travelled was minimized. That means that, if the distribution center can transport goods using vehicles with better fuel consumption, and the drivers can drive in the such a way as to reduce the discharge of carbon, then the proposed method can be a strategy for the continuous improvement of fuel consumption.

Thin film transistor liquid crystal display (TFT‐LCD) is the primary flat panel display (FPD) technology, which is quickly becoming pervasive in many applications including computers, mobile phones, TV monitors, and so on. The finished product of a TFT‐LCD display device is called “module”. A module is subject to a final inspection and packaging (I/P) process before it is shipped to the customer. The I/P operations are primarily manual and the present study seeks to focus on these. The I/P process is strategically important since it directly impacts on both customer service and out‐going quality levels. The operator allocation decision for I/P operations determines the through‐put of the I/P line, and is a function of demand requirement, operator availability, and product dedication.

This research proposes to solve the I/P process operator allocation problem by mixed‐integer programming formulations. A practical case study has been adopted for the empirical illustrations.

Empirical results are promising. The potential improvement is ranging from 9 to 20 percent against the current practice at the case study company.

A structured experimental design shows the effectiveness and efficiency of the proposed formulations in solving the problem of the case study.

The purpose of this paper is to solve an integration of customer and supplier flexibility problem in a make-to-order (MTO) industry. The flexible strategies, where delivery leadtime and unit price (or raw material cost) can be negotiated, are provided by customers and suppliers. Its effectiveness is illustrated by a practical application.

The present study is a rolling decision-making problem and is solved by a proposed combined mixed integer program (MIP) and simulation approach. A simulation model was developed for evaluating solutions of the MIP and will serve as the virtual factory to provide the initial work-in-process status for a new incoming order evaluation.

The experimental results show that when either customers or suppliers provide flexible strategies to the manufacturer, total profits can be increased. Moreover, when both customers and suppliers provide flexibility strategies to the manufacturer simultaneously, total profits can be significantly increased.

An expanded experiment would be of help in realizing the relationship between the flexibility and profit. Moreover, there are other price-sensitivity functions for both customers and suppliers.

A fishing-net manufacturing company was used for the case study to illustrate the effectiveness and the feasibility of the proposed methodology and its application to industry.

The proposed methodology innovatively solved a practical application. The customer and supplier flexibility was investigated in a MTO production system that has no inventory of raw material. The experimental results are promising.

This paper aims to provide a more inclusive perspective on corporate greenwashing. Major ideas from impression management and transaction cost theory (TCT) helped in evaluating the likelihood of greenwashing within the Chinese context.

The sample consists of 184 Chinese public companies – 104 participating and 80 not participating in China’s green watch (GW) program. Using logistic regression, the analysis illustrates the importance of impression management and TCT as indicators of GW participation.

GW participation reduced the likelihood of GW firms joining substantive codes of conduct outside the GW program, indicating an important role of impression management and power relationships; a higher level of firm risk is associated with greater GW participation, signaling a higher level of risk tolerance; and higher levels of asset intensity increase the likelihood of GW participation, indicating a TCT connection.

These findings present a strong case for going beyond greenwashing and further exploring the organizations’ multiple motives for sustainability. They “force” the authors to study impression management and greenwashing from a more “human” perspective.

Besides establishing sustainability legitimacy, substantive codes of conduct enhance a firm’s ability to attract capital – impression management behavior falls within the rules of the game to achieve legitimacy and competitive advantage.

This paper provides a complementary explanation for firms engaging in sustainability acts, beyond that offered by the greenwashing concept. It is demonstrated that firms do not necessarily desire to deceive others, but to realistically impress and influence them, most likely in pursuit of corporate objectives.