• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.87.2-87.2
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• 2010

The steady and dynamic process model for an internal reforming molten carbonate fuel cell power plant is discussed in this paper. The dominant thermal and chemical dynamic processes are modeled for the stack module and balance-of-plant, including cathode gas preparation, heat recovery, heat loss (Each heat loss amount for the stack and MBOP is obtained from real plant data) and fuel processing. Based on dynamic model and control demand, PID controllers are designed in the whole system. By applying these controllers we can obtain temperature balance of stack and control system depending on changing steam to carbon ratio, air feed amount, and transient condition.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.4
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• pp.467-472
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• 2012

In this paper, we present a finite element method (FEM) study on the space charge effects in organic light emitting diodes. The physical model covers all the key physical processes in OLEDs, namely charge injection, transport and recombination, exciton diffusion, transfer and decay as well as light coupling, and thin-film-optics. The exciton model includes generation, diffusion, and energy transfer as well as annihilation. We assumed that the light emission originates from oscillation which thus is embodied as exciton in a stack of multilayer. We discuss the accumulation of charges at internal interfaces and their signature in the transient response as well as the electric field distribution. We also report our investigation on the influence of the insertion of the emission layer (EML) in the bilayer structure.

• International Journal of CAD/CAM
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• v.5 no.1
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• pp.39-47
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• 2005

Different CAx systems are being utilized throughout the product lifecycle due to the practical reasons in the supply chain and design processes. One of the major problems facing enterprises of today is how to share and exchange data among heterogeneous applications. Since different software applications use different terminologies, it is difficult to share and exchange the product data with internal and external partners. This paper presents a method to enhance the CAD model interoperability based on feature ontology. The feature ontology has been constructed based on the feature definition of modeling commands of CAD systems. A method for integration of semantic data has been proposed, implemented, and tested with two commercial CAD systems.

• Knowledge Management Research
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• v.18 no.2
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• pp.103-127
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• 2017

This study examines the effects of failed airline services on the consumers' psychological process and their behavioral responses. Having different classifications from the previous studies, this study focuses on dividing important factors of airline services into search attributes(e.g. sale and procedure services, services concerning flight attendant, in-flight services) and experience attributes(e.g. flight services, collateral services). Using structural equation modeling, this study shows that the failure of service factors of the experience attributes provokes the feeling of disappointment with mediation effect of external attribution while the failure of service factors of search attributes provokes the feeling of regret with mediation effect of internal attribution. Finally, disappointment leads to consumers' complaint behavior while regret leads to consumers' switching behavior. Unlike previous studies, we show that when a service failure occurs, depending on each attribute, consumers feel negative emotions of disappointment or regret through different attribution processes and finally show different behavioral responses with an empirical analysis.

• Knowledge Management Research
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• v.12 no.1
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• pp.39-52
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• 2011

Many LCD manufacturers continue to develop the technologies of LCD manufacturing processes for the reduction of production cost, power consumption and high-resolution. The LTPS (Low Temperature Polycrystalline Silicon) crystallization technology is important for rearranging the internal structure of liquid crystal grain by adding certain energy to amorphous silicon and turning it into poly-silicon in order to manufacture LCD with better performance. We consider 14 existing technologies of LTPS crystallization in the LCD manufacturing and present an intelligent analysis methodology using patent map and AHP (Analytic Hierarchy Process) analysis for determining an optimal LTPS crystallization technology. By using patent map analysis, we easily understand the development process and mega-trend of LTPS crystallization technologies and their relationship. By using AHP analysis, we evaluate 14 LTPS technologies. Through the use of proposed methodology, we determine the Continuous Wave Laser Lateral Crystallization technology as an optimal one.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.58-61
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• 2001

An implicit finite element formulation for axisymmetric tube hydroforming is investigated. In order to describe normal anisotropy of the tube, Hill's non-quadratic yield function is employed. The frictional contact between die and tube and frictionless contact between tube and fluid are considered using the mesh-normal vector computed from finite element mesh of the tube. In order to verify the validity of the developed finite element formulation, the axisymmetric tube bulge test is simulated and simulation results are compared with experimental measurements. In the axisymmetric tube hydroforming process, an optimal hydraulic curve is pursued by performing the simulation with various internal pressures and axial forces.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.233-236
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• 2003

A bumper comprises a bumper face, a bumper beam for distributing the load from the impacts applied to the bumper face and reinforcing the bumper, an absorber member interposed between the bumper face and the bumper beam, and a pair of bumper stays which secure the bumper beam to the vehicle body. A conventional bumper stay structure is assembled into several stamped parts, so several processes are needed and the structure is complicated. In this study the bumper stay is applied to the tubular hydroforming which is known to have several advantages such as the reduction of the number of the process and the part weight. The thickness distribution of the tube after hydroforming and the internal energy at the event of the a compression are mainly considered to evaluate the hydro-formability and energy absorption performance.

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.167-180
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• 1997

Data semantics is an well recognized issue in areas of information systems research. It provides indispensable information for management of data, It describes what data mean, how they are created, where they can be applied to, to name a few. Because of these diverse nature of data semantics, it has been described from different perspectives of formalization. This article proposes to formalize data semantics by the processes that data are created or transformed, A scheme is proposed to describe the structure that data are created and transformed, which is called Bill of Data. Bill of Data is a directed graph, whose leaves are primary input data and whose internal nodes are output data objects produced from input data objects. Using Bill of Data, algorithms are developed to compare data semantics.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.60-63
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• 2001

Investigating electromagnetic emissions of inverter power sources for resistance welding existing special aspects of EMI measurements in the field of resistance welding machines resulting from the power rating and intermittent operation mode of these machines have to be taken into account. The characteristics of the internal switching processes determined by the behavior of the applied power semiconductors, snubber circuits and constructional aspects exert a great influence on the conducted emission of resistance welding inverters.

• Journal of Information Technology Applications and Management
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• v.11 no.4
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• pp.1-23
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• 2004

This study identifies communication patterns of groups using synchronous text communication medium for their group decision-making, and examines how these patterns are associated with creative solutions to problems. Our research suggests that certain communication behavior of groups, when appropriately organized, can be of help in enhancing creative production of outcomes. A qualitative study was conducted on communication patterns based on an analysis of text-based electronic conversation protocols. Specifically this research tried to overcome existing studies on electronic groups by focusing on interactive process of communication among participants. The major study conclusion; are: (1) The production of creative outcome may depend on the process or sequence of discussion among group members with synchronous text communication medium. That is, proper interactive responses and appropriate control of the discussion process are essential to obtain a high level of performance. (2) It is importantto make discuss rules based on meta-cognitive and interactive protocols in the early stage. Explicit rules relating to internal group processes as well as communication medium use are even more important to groups with electronic communication medium than face-to-face groups.