• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.54-60
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• 2014

In industry, several casting process are widely used to manufacture complex and accurate blank part of hard materials such as aluminum, casting steels, bronze and magnesium alloys which are difficult to manufacture in a blank shape. Even if the casting process does not high accuracy superior surface characteristics other machining process, the casting process is widely used in manufacturing blank part. Furthermore, it is difficult to select appropriate casting process a part among several casting process. for effective selection different process, a careful decision given casting application is necessary. An appropriate casting for a given material and shape condition must be selected for novice engineers in industry. In this paper, an expert system based on an analytic network process(ANP) is suggested for best selection of casting considering a prior interdependency effect among various factors such as material, geometry, process capability, economy and equipment.

• Journal of Wetlands Research
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• v.9 no.1
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• pp.61-67
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• 2007

Our life totally depends on activated sludgeprocess for treatment of wastewater: sewage and industrial wastewater. Activated sludge process was the epoch-making technology in Environmental field. One century has been almost passed since the process was developed in England, and the process is still on the development of improvement. Here, history of activated sludge process, its mechanismsof treating the wastewater, expectations that we had on the process in the past, and future image and possibility on the process were presented. By reviewing the events related to the process, we can foresee potentials for new possibility of activated sludge process.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.212-221
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• 2018

Process safety incidents and loss events can be prevented if we identify and adequately take measures on process safety incident precursors in a timely manner. If we look into and take action against the process safety hazard factors causing the incident in the refinery and petrochemical plant, major process safety incidents can be prevented through eliminating or decreasing hazardous factors. We conducted a survey for the major process safety incident precursor to look specifically into the potential process safety hazardous factors of refineries and petrochemical plants in the Yeosu chemical complex. A self-assessment checklist, which was published by Center for Chemical Process Safety "Recognizing catastrophic incident warning signs in the process industry" on major incidents warning sign, was used for the survey. Through this survey, the major process safety incident leading indicators in the process industry were found by process safety management elements, and each site and/or facility can use these leading indicators for activities for process safety incident prevention. In addition, we proposed action items required to eliminate the root cause of those process safety incident leading indicators.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.279-288
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• 2007

Attempts to achieve a higher productivity have led studies to focus on process improvement. Information has been found as an essential element for process improvement. This research has introduced and focused on two types of information, namely: related jobsite information along the process and feedback information. Related jobsite information along the process which needs to be processed and delivered in a timely manner, accurate, and real time is required to streamline the decision making process. Whereas feedback information about process' current practices which have to be captured and stored is a useful for continuous improvement in identifying the problem origin and determining corrective action. In the current practices, although these two types of information are essential for process improvement, construction process has faced barriers in obtaining that information. Therefore, this research will propose a new information system to overcome the aforementioned barriers. The new information system consists of RFID as an automatic identification and data collection device integrated with database to support construction processes. The new system attempts to provide related jobsite information along the process and feedback information to support decision making process and continuous process improvement respectively. A case study of prefabrication installation process in housing projects has been selected to be implemented in conceptual model of RFID application in construction industry. Conceptual model will be presented in this paper as an initial stage of this ongoing research. Expected outcomes of the new system and future works will be discussed briefly.

• Journal of Applied Reliability
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• v.13 no.4
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• pp.273-285
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• 2013

Because process variations have direct influence on yield rate in process industry, it is very important to understand process variations that occur accidentally. In process industry, quality variation due to the activities of process improvement and maintenance and chance effect such as change of work environment and difference in staffs' craftsmanship are mixed with each other, therefore it is difficult to actually detect minute process variations. In this study, objective and rational methods of detection that can detect minute process variations in process industry were designed referring to various methodologies of process management, and they were verified through similar examples.

• Transactions of Materials Processing
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• v.8 no.2
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• pp.188-199
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• 1999

Semi-Solid Forming Process(Thixoforming, Rheocasting) is a novel forming process which has some advantages compared with conventional die casting, squeeze casting and hot/cold forging. In this study. Thixoforming process was selected as analysis processing in terms of billet handling and easiness of automation process. The Thixoforming process consists of reheating process of billet, billet handling, filling inot the die cavity and solidification of SSM part. In filling process, two rheology models which were Newtonian and Non-Nettonian model (Ostwald-deWaele)were verified with experimental results. The Ostwald-deWaele model shows the good agreement to the real flow and filling phenomena in die cavity. To give a boost the economical efficiency of Thixoforming process and to ensure the good forming result, reheating device coupled die set was proposed and the initial billet temperature for system that was found from experimental resluts. This study presents an overview of application of numerical analysis for simulation of semi-solid metal forming process to reduce the lead time for development of manufacturing part in industrial field.

• Proceedings of the Safety Management and Science Conference
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• 2005.11a
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• pp.493-504
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• 2005

Statistical Process Control and Process Adjustment theory is gaining recognition in the process industries where the process frequently experiences a shift mean. This paper aims to study, the theory difference between Statistical Process Control and Process Adjustment in simple terms and presents a case study that demonstrates successful integration of Statistical Process Control and Process Adjustment theory for a product in drifting industry.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.9
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• pp.875-880
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• 2015

Traditional semiconductor process control has been performed through statistical process control techniques in a constant process-recipe conditions. However, the complexity of the interior of the etching apparatus plasma physics, quantitative modeling of process conditions due to the many difficult features constraints apply simple SISO control scheme. The introduction of the Advanced Process Control (APC) as a way to overcome the limits has been using the APC process control methodology run-to-run, wafer-to-wafer, or the yield of the semiconductor manufacturing process to the real-time process control, performance, it is possible to improve production. In addition, it is possible to establish a hierarchical structure of the process control made by the process control unit and associated algorithms and etching apparatus, the process unit, the overall process. In this study, the research focused on the methodology and monitoring improvements in performance needed to consider the process management of future developments in the semiconductor manufacturing process in accordance with the age of the APC analysis in real applications of the semiconductor manufacturing process and process fault diagnosis and control techniques in progress.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1217-1233
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• 2017

Effective monitoring and testing during each step are essential for document verification in research and development (R&D) projects. In software development, proper testing is required to verify it carefully and constantly because of the invisibility features of software. However, not enough studies on test processes for R&D projects have been done. Thus, in this paper, we introduce a Test Maturity Model integration (TMMi)-based software field R&D test process that offers five integrity levels and makes the process compatible for different types of projects. The Software & Systems Process Engineering Metamodel (SPEM) is used widely in the software process-modeling context, but it lacks built-in enactment capabilities, so there is no tool or process engine that enables one to execute the process models described in SPEM. Business Process Model and Notation (BPMN)-based workflow engines can be a solution for process execution, but process models described in SPEM need to be converted to BPMN models. Thus, we propose an approach to support enactment of SPEM-based process models by converting them into business processes. We show the effectiveness of our approach through converting software R&D test processes specified in SPEM in a case study.

• Journal of the Korean Data and Information Science Society
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• v.18 no.3
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• pp.773-782
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• 2007

The statistical process control charts are very extensively used for monitoring of process mean, deviation, defect rate or reject rate. In this paper we consider a control chart to monitor the process reject rate in the high yield process, which is based on the observed cumulative probability of the number of items inspected until r defective items are observed. We first propose selection of the optimal value of r in the CPC-r charts, and also consider the usefulness of the chart in high yield process such as semiconductor or TFT-LCD manufacturing process.