• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.621-635
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• 2020

Water quality models are scientific tools that simulate and interpret the relationship between physical, chemical and biological reactions to external pollutant loads in water systems. They are actively used as a key technology in environmental water management. With recent advances in computational power, water quality modeling technology has evolved into a coupled three-dimensional modeling of hydrodynamics, water quality, and ecological inputs. However, there is uncertainty in the simulated results due to the increasing model complexity, knowledge gaps in simulating complex aquatic ecosystem, and the distrust of stakeholders due to nontransparent modeling processes. These issues have become difficult obstacles for the practical use of water quality models in the water management decision process. The objectives of this paper were to review the theoretical background, needs, and development status of water quality modeling technology. Additionally, we present the potential future directions of water quality modeling technology as a scientific tool for national environmental water management. The main development directions can be summarized as follows: quantification of parameter sensitivities and model uncertainty, acquisition and use of high frequency and high resolution data based on IoT sensor technology, conjunctive use of mechanistic models and data-driven models, and securing transparency in the water quality modeling process. These advances in the field of water quality modeling warrant joint research with modeling experts, statisticians, and ecologists, combined with active communication between policy makers and stakeholders.

• Journal of Educational Research in Mathematics
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• v.27 no.1
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• pp.69-88
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• 2017

One of the most important activities in the process of mathematical modeling is to build models by conjecturing mathematical rules and principles in the real phenomena and to validate the models by considering its validity. Due to uncertainty and ambiguity inherent real-contexts, various strategies and solutions for mathematical modeling can be available. This characteristic of mathematical modeling can offer a proper environment in which creativity could intervene in the process and the product of modeling. In this study, first we analyze the process and the product of mathematical modeling, especially focusing on the students' models and validating way, to find evidences about whether modeling can facilitate students'creative thinking. The findings showed that the students' creative thinking related to fluency, flexibility, elaboration, and originality emerged through mathematical modeling.

• Journal of Gifted/Talented Education
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• v.19 no.1
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• pp.187-205
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• 2009

The purpose of this study was to investigate the perception of science high school students for modeling module that contain scientists' thinking process. Modeling modules about 'gas diffusion', 'ion conductivity' and 'ion mobility' were applied to science high school students. Interview, lab report, and dialogue were analyzed to comprehend features of modeling module. Students who performed modeling modules perceived that modeling modules were appropriate to experience scientists' research process. Modeling modules were kind of activity to raise 'muscle of thinking', to be needed 'new views' and 'various representations', and to contain 'designing laboratory process'. Therefore, the development of various modeling modules is needed in the near future.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.34-44
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• 1997

This study presents the recursive constraint bounding(RCB) method to reduce the cycle time in internal cylindrical plunge grinding process. This method can cope with process noise as well as modeling bias. The main features of RCB method are its utilization of measurements at the end of each cycle and its use of monotonicity analysis for determining the extremes of bias and noise. This method is investigated in simulation and evaluated by experiment in internal cylindrical plunge grinding operation. The results from simulation and experiment show that it is effective in reducing cycle time in spite of modeling uncertainty in the forms of process noise and modeling bias.

• IE interfaces
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• v.18 no.4
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• pp.390-401
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• 2005

In this paper, we propose an efficient internet-based logistics brokerage concept which can overcome the weakness of the traditional off-line method to intermediate between vehicle owners and shippers for matching empty vehicles and freights. For defining a business model based on the new concept and implementing an information system, it is necessary to analyze the business process for the internet-based logistics brokerage using a modeling methodology. In this paper, we analyze the logistics brokerage process using the UN/CEFACT Modeling Methodology (UMM) being utilized as a standard modeling methodology in the area of electronic commerce. After analyzing the business process, we can expect that the UMM can be used as a useful tool for modeling the business process of electronic commerce in which the description of the collaborative work is very important.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.42-51
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• 1999

An experimental modeling of cutting and structural dynamics and the on-line detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics of cutting process but also for the analytic realization of diagnostic systems. In this regard, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision round shape machining such as turning, drilling and boring in mold and die making. In this study, simulation and experimental work were performed to show the malfunctioned behaviors. For this purpose, two new recursive approach (REIVM, RLSM) were adopted fur the on-line system identification and monitoring of a machining process, we can apply these new algorithm in real process for the detection of abnormal machining behaviors such as chipping, chatter, wear and round shape lobe waviness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.128-134
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• 2008

Models of the deposition heights in the uncontrolled laser aided direct metal deposition process are constructed for the enhancement of the process integrity. Linear and non-linear statistical models as well as fuzzy model are utilized as the modeling methods. The predictability of the models are evaluated with the values of the sum of square error. The algorithm to use the models in the feedback controlled system is suggested to increase the deposition height accuracy within a layer.

• Macromolecular Research
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• v.10 no.4
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• pp.194-203
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• 2002

In resin infusion process(RIP), the fiber and the resin are in contact with each other for an impregnation step and often results in flow-induced defects such as poor fiber wetting and void formation. Resin flow characteristics in transverse direction and process modeling for woven fabric were studied, and the process modeling was applied to the manufacturing of hybrid composite materials. This study also considered the compressibility of woven fabrics in a series of compression force, and it was fitted well to an elastic model equation. Void formation was varied with the processing conditions in the stage of manufacturing composites using RIP. It was concluded from this study that proper combination of pressure build-up and dynamic heating condition makes important factor for flow-induced composite processing.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.71-88
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• 2006

A business process specification (BPS) plays the role of a contracted business scenario in the execution of the B2B business process instances. XML based specification languages, such as BPSS, WS BPEL, etc., are usually adopted for the specifications. However, composing complex XML based specifications are not easy for humans. As an alternative, graphical modeling languages such as UML and BPMN can be employed. This paper presents an UML based modeling method for graphically specifying ebXML BPSS instances (namely, business process specifications). UML diagrams, directly matching with ebXML BPSS, can be reused for understanding and generating ebXML BPSS instances. We discuss the value of the method by developing a business reference library in the area of supply chain management.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2006.06a
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• pp.629-655
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• 2006

A business process specification (BPS) plays the role of a contracted business scenario in the execution of the B2B business process instances. XML-based specification languages, such as BPSS, WS-BPEL, etc., are usually adopted for the specifications. However, composing complex XML-based specifications are not easy for humans. As an alternative, graphical modeling languages such as UML and BPMN can be employed. This paper presents an UML-based modeling method for graphically specifying ebXML BPSS instances (namely, business process specifications). UML diagrams, directly matching with ebXML BPSS, can be reused for understanding and generating ebXML BPSS instances. We discuss the value of tile method by developing a business reference library in the area of supply chain management.