• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.153-166
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• 2016

Purpose: Government quality assurance (QA) activities in Korea, which is carried out by the Defense Agency for Technology and Quality, is not effective due to 1) the obscureness of the QA implementation method, 2) the gap between QA activities of provisions and those conducted in the fields, and 3) the variation in subjective judgement among the QA personnel. The purpose of this paper is to propose some suggestions to enhance the effectiveness of government QA activities for military supplies in the production stage. Methods: QA activities for military supplies are investigated and problematic aspects are deduced for the production stage. To secure the effectiveness of the QA activities, Defense Contract Management Agency of the United Sates is benchmarked and five improvement methods are presented. Results: Five improvement aspects are 1) reflecting special terms and conditions of government mandatory inspection in contract, 2) classifying QA personnel, 3) making use of data collection and analysis template compulsory, 4) providing checklist for process review, and 5) establishing guidelines for sampling plans for product examination. Conclusion: Suggestions of this paper can lead to consistency and balance in government QA activities, reducing military suppliers' complaints and enhancing the effectiveness of QA effort, and ultimately contributing to the quality improvement of military supplies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.63-72
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• 2017

This paper proposes a procedure to improve the operational efficiency of the automotive parts manufacturing process by applying classical IE techniques composed of process analysis, work method analysis, and motion analysis, and a specific application case is outlined. The proposed procedure was developed originally by the Task Force organized in L company's automotive parts manufacturing business unit. The balance efficiency and production capacity were used as measures of operational efficiency. The developed procedure follows the general procedure of analyzing the phenomenon at the manufacturing shop, deriving an improvement solution to solve the problem, evaluating each derived alternative, and implementing it to the field to achieve productivity improvement. Among the methods used in each phase of the procedure, function analysis used in the waste discovery phase and R&R evaluation method used in the alternative assessment phase are unique techniques developed by L company's TF. The R&R Evaluation method techniques are described in detail because this method is highly applicable and extensible. A case of applying developed procedures to improve the EPS motor manufacturing process is discussed. As a result, the line balance efficiency and production capacity were increased to a satisfactory level.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.428-439
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• 2020

The continuous development of information and communication technologies has resulted in an exponential increase in data. Consequently, technologies related to data analysis are growing in importance. The shipbuilding industry has high production uncertainty and variability, which has created an urgent need for data analysis techniques, such as machine learning. In particular, the industry cannot effectively respond to changes in the production-related standard time information systems, such as the basic cycle time and lead time. Improvement measures are necessary to enable the industry to respond swiftly to changes in the production environment. In this study, the lead times for fabrication, assembly of ship block, spool fabrication and painting were predicted using machine learning technology to propose a new management method for the process lead time using a master data system for the time element in the production data. Data preprocessing was performed in various ways using R and Python, which are open source programming languages, and process variables were selected considering their relationships with the lead time through correlation analysis and analysis of variables. Various machine learning, deep learning, and ensemble learning algorithms were applied to create the lead time prediction models. In addition, the applicability of the proposed machine learning methodology to standard work hour prediction was verified by evaluating the prediction models using the evaluation criteria, such as the Mean Absolute Percentage Error (MAPE) and Root Mean Squared Logarithmic Error (RMSLE).

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.337-348
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• 2015

This research introduces the Financial Effect Measurement (FEM) models which measures both the improvement and the innovation performance of Quality Control Circle (QCC) and activities of Six Sigma. Concepts and principle of Comprehensive Income Statement (CIS), Balanced Scorecard (BSC), Time-Driven Activity Based-Costing (TDABC) and Total Productive Maintenance (TPM) are applied in order to develop the 4 FEM models presented in this paper. First of all, FEM using CIS depicts the improvement effects of production capacity and yield using relationships between demand and supply, and line balancing efficiency between bottleneck process and non-bottleneck processes. Secondly, cause-and-effect relation of Key Performance Indicator (KPI) is used to present Critical Success Factor (CSF) effects for QC Story 15 steps of QCC and DMAIC (Define, Measure, Analyze, Improve, and Control) of Six Sigma. The next is FEM model for service management innovation activities that uses TDABC to calculate the time-driven effect for improving the indirect activities according to the cost object. Lastly, FEM model for TPM activities presents the interpretation of improvement effect model of TPM Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) maintenance using profit, cash and Economic Added Value (EVA) as metrics of enterprise values. To better understand and further investigate FEMs, recent cases on National Quality Circle Contest are used to evaluate new financial effect measurement developed in this paper.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.6 s.261
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• pp.522-530
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• 2007

The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method and the composition analysis for data collection and data analysis were respectively used in the main board and the cellular phone module production lines. And these methods were evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. While in case that the composition analysis was applied, the critical sources were selected and yield loss reduction through improvement actions was also investigated. From these results, it is concluded that the partition check and the composition analysis are effective solutions for particle contamination control in the cleanroom production lines.

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.21-31
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• 2013

There is a high demand for the diagnostic medical blood analyzer in the global medical device market. The domestic market is in infant stage, but expected to grow very fast. In this study, we attempt to provide several ways for production improvement in order to secure price competitiveness of domestic medical blood analyzer. For this purpose we identify the problems of current production process using ARENA simulation and suggest several alternatives for productivity improvement.. Five steps of TOC (Theory of Constraints) and ARENA simulation are employed to predict productivity of each alternative and to suggest further improvement.

• Transactions of Materials Processing
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• v.16 no.7
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• pp.555-560
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• 2007

This paper shows some achievements at bending of extruded aluminum profiles during the extrusion process. The conventional process for the production of bent profiles involves a successive extrusion, stretching, and bending of the profiles. Conventional bending methods can not meet demands far precision and cost-effective production in some cases, due to cross sectional deformation, irregular decrease of tube wall thickness and a complication of the process design. An estimation of spring-back required for precision of the bending radius can not always be achieved by the over bending of the profile. Since the profile is hot during the bending process, the spring-back phenomenon can be avoided. This means that an additional bending process is not necessary. Consequently, flexible bending can be achieved with cost reduction and quality improvement. Experimental tests were completed to study the relationship between curvature radius of profile and position of guide on the extrusion for vehicle bumper. A7108 is applied as a billet material in order to increase strength. The overall correlation between the experimental and numerical results is good. It is therefore concluded that the present method provides an efficient means for the constant curvature extrusion process.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.5
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• pp.87-97
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• 2008

Importance of service competitive power is greatly increasing. Domestic enterprises are recognizing the importance of service competitive power, but the correspondence is insufficient level. Because service has the characteristic that production and consumption synchronizes, it can be considered as process. In this study, we utilize the process reform by plan for service competitive power elevation. We divide service process reform by four types based upon special quality of goods(form and formlessness) and reform target (new process design and existing process improvement), and present various examples by each type. On the this basis, we suggest the specific elevation plan of competitive power.

• Journal of Hydrogen and New Energy
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• v.33 no.5
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• pp.515-524
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• 2022

In this study, the on-site hydrogen production process for refueling stations that were not energy-optimized was improved through exergy analysis and heat exchange network synthesis. Furthermore, the process was scaled up from 30 Nm3/h to 150 Nm3/h to improve hydrogen production capacity. Exergy analysis results show that exergy destruction in the SMR reactor and the heat exchanger accounts for 58.1 and 19.8%, respectively. Thus, the process is improved by modifying the heat exchange network to reduce the exergy loss in these units. As a result of the process simulation analysis, thermal and exergy efficiency is improved from 75.7 to 78.6% and 68.1 to 70.4%, respectively. In conclusion, it is expected to improve the process efficiency when installing on-site hydrogen refueling stations.

• IE interfaces
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• v.21 no.4
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• pp.403-410
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• 2008

Manufacture enterprise's environment is felt difficulty more and more by suddenly rise of oil and raw material price lately. In such difficult environment, Toyota Productive System is becoming good example to all enterprises because Toyota competitive power is rising every year. Now, Toyota Company is becoming benchmarking target. In this paper, we survey Toyota Production System, we try to apply advantage of Toyota Production System to Office Work. We propose TOOF (TOyota OFfice) system which is applied to modifying Toyota Production System in financial aid Business. We hope that Office Work are improved through TOOF system.