Junhee Han

Prof. Junhee Han

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 June 2020 in Sustainability
Verified
Journal Article
Open access
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GHgyusun hwang
gyusun hwang
JHJunhee Han
Junhee Han
TCTai-Woo Chang
Tai-Woo Chang
This paper proposes a comprehensive production performance measurement framework and illustrates the method to evaluate the performance and guide practitioners to make further improvement. The development comprises four steps. (1) Performance indicators derived from business excellence models are enumerated to provide the performance model: 74 indicators, which can be classified in terms of their characteristics, are identified in six criteria. (2) A multiple criteria decision-making approach based on the analytic hierarchical and network processes, which determine the weights of the criteria and indicators, is applied. In addition, this study introduced additional formulas to derive the final performance values. (3) A performance measurement framework that integrates the measurement and result analysis processes is implemented. (4) The proposed framework is verified through a case study. The results of the case study show that the proposed framework identifies the gaps and discrepancies among the management levels, enabling the determination of means for continuous improvement.

3 October 2022 in Engineering Optimization
Verified
Journal Article
Open access
JHJunhee Han
Junhee Han
JLJu-Yong Lee
Ju-Yong Lee
Semiconductor manufacturing systems consist of highly complex and constrained processes owing to the requirement for high-quality wafers and dynamic customer orders. This study focuses on waiting time constraints to achieve high-quality wafers, with missing operations, to manufacture different types of orders, which are common scheduling requirements in semiconductor manufacturing systems. Waiting time constraints limit the waiting times between consecutive machines. Although sequential steps are modelled as a flow shop, some jobs can skip some steps in the flow shop. Such jobs can accordingly skip certain machines in the flow shop, which is called ‘missing operations’. This research investigates a scheduling problem for a flow shop with waiting time constraints and missing operations. A mathematical programming formulation and scheduling algorithms are proposed to operate such a flow shop efficiently. Through computational experiments, the proposed algorithms were evaluated, and analysis of various parameters for waiting time constraints and missing operations was conducted.

3 November 2021 in Algorithms
Verified
Journal Article
Open access
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BJBongjoo Jeong
Bongjoo Jeong
JHJunhee Han
Junhee Han
JLJu-Yong Lee
Ju-Yong Lee
This study considers a scheduling problem for a flow shop with urgent jobs and limited waiting times. The urgent jobs and limited waiting times are major considerations for scheduling in semiconductor manufacturing systems. The objective function is to minimize a weighted sum of total tardiness of urgent jobs and the makespan of normal jobs. This problem is formulated in mixed integer programming (MIP). By using a commercial optimization solver, the MIP can be used to find an optimal solution. However, because this problem is proved to be NP-hard, solving to optimality requires a significantly long computation time for a practical size problem. Therefore, this study adopts metaheuristic algorithms to obtain a good solution quickly. To complete this, two metaheuristic algorithms (an iterated greedy algorithm and a simulated annealing algorithm) are proposed, and a series of computational experiments were performed to examine the effectiveness and efficiency of the proposed algorithms.

26 November 2021 in Applied Sciences
Verified
Journal Article
Open access
PDF file
JHJunhee Han
Junhee Han
JLJu-Yong Lee
Ju-Yong Lee
This study investigates a two-stage assembly-type flow shop with limited waiting time constraints for minimizing the makespan. The first stage consists of m machines fabricating m types of components, whereas the second stage has a single machine to assemble the components into the final product. In the flow shop, the assembly operations in the second stage should start within the limited waiting times after those components complete in the first stage. For this problem, a mixed-integer programming formulation is provided, and this formulation is used to find an optimal solution using a commercial optimization solver CPLEX. As this problem is proved to be NP-hard, various heuristic algorithms (priority rule-based list scheduling, constructive heuristic, and metaheuristic) are proposed to solve a large-scale problem within a short computation time. To evaluate the proposed algorithms, a series of computational experiments, including the calibration of the metaheuristics, were performed on randomly generated problem instances, and the results showed outperformance of the proposed iterated greedy algorithm and simulated annealing algorithm in small- and large-sized problems, respectively.

17 October 2021 in Applied Sciences
Verified
Journal Article
Open access
PDF file
JHJunhee Han
Junhee Han
JLJu-Yong Lee
Ju-Yong Lee
BJBongjoo Jeong
Bongjoo Jeong
This study considers a production planning problem with a two-level supply chain consisting of multiple suppliers and a manufacturing plant. Each supplier that consists of multiple production lines can produce several types of semi-finished products, and the manufacturing plant produces the finished products using the semi-finished products from the suppliers to meet dynamic demands. In the suppliers, different types of semi-finished products can be produced in the same batch, and products in the same batch can only be started simultaneously (at the same time) even if they complete at different times. The purpose of this study is to determine the selection of suppliers and their production lines for the production of semi-finished products for each period of a given planning horizon, and the objective is to minimize total costs associated with the supply chain during the whole planning horizon. To solve this problem, we suggest a mixed integer programming model and a heuristic algorithm. To verify performance of the algorithm, a series of tests are conducted on a number of instances, and the results are presented.

6 November 2024 in Maritime Policy & Management
Verified
Journal Article
Closed access
SNSiti Nurminarsih
Siti Nurminarsih
YJYoonjea Jeong
Yoonjea Jeong
BKBosung Kim
Bosung Kim
JHJunhee Han
Junhee Han