• Journal of the Semiconductor & Display Technology
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• v.5 no.4 s.17
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• pp.29-34
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• 2006

In order to design an OLED(Organic Luminescent Emitting Device) evaporation system, geometric simulation of film thickness distribution profile is required. For the OLED evaporation process, thin film thickness uniformity is of great practical importance. In this paper, a geometric modeling algorithm is introduced for process simulation of the OLED evaporating process. The physical fact of the evaporating process is modeled mathematically. Based on the developed method, the thickness of the thin-film layer can be successfully controlled.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.252-255
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• 2003

The pulsed laser deposition process modeling is investigated using neural networks based on radial basis function networks and multi-layer perceptron. Two input factors are examined with respect to the PL intensity. In order to minimize the joint confidence region of fabrication process with varying the conditions, D-optimal experimental design technique is performed and photoluminescence intensity is characterized by neural networks. The statistical results were then used to verify the fitness of the nonlinear process model. Based on the results, this modeling methodology can be optimized process conditions for pulsed laser deposition process.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2327-2335
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• 2018

Fluid catalytic cracking (FCC) is an important chemical process that is widely used to produce valuable petrochemical products by cracking heavier components. However, many difficulties exist in modeling the FCC process due to its complexity. In this study, a dynamic process model of a FCC process is suggested and its structural observability is analyzed. In the process modeling, yield function for the kinetic model of the riser reactor was applied to explain the product distribution. Hydrodynamics, mass balance and energy balance equations of the riser reactor and the regenerator were used to complete the modeling. The process model was tested in steady-state simulation and dynamic simulation, which gives dynamic responses to the change of process variables. The result was compared with the measured data from operating plaint. In the structural analysis, the system was analyzed using the process model and the process design to identify the structural observability of the system. The reactor and regenerator unit in the system were divided into six nodes based on their functions and modeling relationship equations were built based on nodes and edges of the directed graph of the system. Output-set assignment algorithm was demonstrated on the occurrence matrix to find observable nodes and variables. Optimal locations for minimal addition of measurements could be found by completing the whole output-set assignment algorithm of the system. The result of this study can help predict the state more accurately and improve observability of a complex chemical process with minimal cost.

• Korean Journal of Computational Design and Engineering
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• v.6 no.3
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• pp.157-168
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• 2001

The description of enterprise activities is the basis fur process improvement and information system building. To describe such activities, it is necessary to model the enterprise activities from the abstraction level to the implementation level in a stepwise and integrated form. For this reason, several modeling approaches have been proposed. However, most of them lacked the stepwise or integration aspects although some of them covered overall levels. This study proposes the hierarchical modeling approach for integrating the enterprise activity model from the abstraction level to the implementation level systematically. It is composed of five modeling levels such as function level, process level, task level, document workflow level, and event flow level. This study discusses the definition and characteristics of each level and compare our modeling frame with other modeling methodologies in case study.

• Journal of Korea Multimedia Society
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• v.11 no.4
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• pp.525-543
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• 2008

Recently, the scope of user interface is increasing the relative importance in software development dramatically. As a result, there are various relative technologies like as SWING, MFC, Web 2.0, and etc. However, most current software developments are progressed in separate development process with user interface part and business part respectively. This causes the problems, like as a difficulty in the integration process, an development period's delay, and a poor reusability for the constructed models. That is, the extendability and reusability of the created models is being decreased because UI modeling is not systematic and hierarchical, and the consistent integration technique between UI modeling and business modeling does not supported. To solve these problems, this paper proposes an unified and systematic UI modeling process based on UML, using the hierarchical metamodel according to the abstraction levels of development phase. We suggest an UI metamodel, which contains a hierarchy by layering the modeling elements in PIM and PSM based on maturity degree of the development. An hierarchical modeling process combined UI modeling and business modeling is built by applying the UI and business metamodel in terms of three modeling phases(concept/specification/concrete). The effectiveness of the modeling process is shown by applying the proposed process into an Internet Shopping Mall System. Through the exploratory results, the hierarchical UI metamodel and process can produce systematic and layered UI models. This can improve the quality and reusability of models.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.4
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• pp.227-238
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• 2013

The business based existing BPMN model is a lack of service oriented modeling techniques. Therefore, it requires a layered technique of service oriented business modeling so that can meet the design for a complex application system, developing a system based on SOA. In order to enhance reusability and modularity of BPMN business model, this paper proposes a metamodel and business modeling process based on this metamodel that can hierarchically build a BPMN model. Towards this end, the XL-BPMN metamodel hierarchically established based on MDA and MVS styles are first defined. Then a BPMN service modeling process is constructed based on modeling elements of this metamodel according to the modeling phases. Finally, the result of a case study in which the proposed method is applied to an online shopping mall system is discussed. With the use of well-defined metamodel and modeling process, it is hoped that it can be shown that a service dominated and layered BPMN business model can be established, and that the modularity and reusability of the constructed BPMN business model can be maximized.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.487-490
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• 2004

In order to simulate OLED evaporation process, modeling of directional distribution of the vaporized organic materials, film thickness distribution profile and pattern-mask shadow effect are required In accordance with many literatures; all of them except shadow effect modeling are studied and developed. In this paper, modeling algorithm of evaporation shadow is presented for process simulation of full-color OLED evaporating system. In OLED evaporating process the offset position of the point cell-source against the substrate rotation axis and the usage of the patterned mask are the principal causes for evaporation shadow. For geometric simulation of shadow using z-map, the film thickness profile, which is condensed on a glass substrate, is converted to the z-map data. In practical evaporation process, the glass substrate is rotated. This physical fact is solved and modeled mathematically for z-map simulation. After simulating the evaporation process, the z-map data can present the shadow-effected film thickness profile. Z-map is an efficient method in that the cross-sectional presentations of the film thickness profile and thickness distribution evaluation are easily and rapidly achieved.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.133-136
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• 2000

In recent years, hybrid neural network approaches which combine neural networks and mechanistic models have been gaining considerable interests. These approaches are potentially very efficient to obtain more accurate predictions of process dynamics by combining mechanistic and neural models in such a way that the neural network model properly captures unknown and nonlinear parts of the mechanistic model. In this work, such an approach was applied in the modeling of a full-scale coke wastewater treatment process. First, a simplified mechanistic model was developed based on the Activated Sludge Model No.1 and the specific process knowledge, Then neural network was incorporated with the mechanistic model to compensate the errors between the mechanistic model and the process data. Simulation and actual process data showed that the hybrid modeling approach could predict accurate process dynamics of industrial wastewater treatment plant. The promising results indicated that the hybrid modeling approach could be a useful tool for accurate and cost-effective modeling of biochemical processes.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.2
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• pp.190-194
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• 2004

This paper shows the application of fuzzy system for a modeling of nonlinear biochemical process. A wastewater treatment process for nitrogen removal in a sequencing batch reactor (SBR) is presented and fuzzy systems with different consequent polynomials in the fuzzy rules to model and identify the oxidation reduction potential (ORP) of the process are introduced. The paper compares, analyzes the results of fuzzy modeling, and shows the nonlinear process can be modeled reasonably well by the present scheme.

• The Journal of Society for e-Business Studies
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• v.3 no.2
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• pp.141-160
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• 1998

In order to achieve a successful introduction of CALS, an enterprise model which is a concise description of what an enterprise does is required. The enterprise model mainly consists of a process model and a data model. The process model describes processes that create, change, combine, or destroy the entities within the enterprise. Several process modeling methodologies have been proposed. Each modeling methodology requires its own modeling view point, elements, and syntax. In developing a process model for CALS, these models created at different view points are required to analyze and design a system in a broad view. This paper aims at proposing an integration methodology for a process model. Specifically, IDEF0, IDEF3, and Petri Net are considered to be integrated. An IDEF0 model describing static functions of enterprise is transformed to an IDEF3 model describing behaviour of a system with additional information. Also, the IDEF3 model is transformed to a Petri Net model. These transformations will be automatically accomplished once the additional information for the transformation is provided.