• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 추계 학술대회논문집
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• pp.152-157
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• 1999

For the simulation of the blood flow in coronary artery, the system modeling of coronary hemodynamics is combined with CFD technique. The blood flow in coronary artery interacts with the global coronary circulation. Especially in case of the coronary artery with stenosis, the interaction plays an important role in the hemodynamics of the circulation. In this study we present a combined numerical approach using both the CFD technique for flow simulation and the global system model of coronary circulation. We use a lumped parameter model for the global simulation of coronary circulation whereas the finite element method is employed to compute the viscous flow field in stenosed coronary artery, The time variation of the pressure drop due to stenosis is obtained from the proposed numerical method. Numerical results shows that the flow resistance and pressure drop due to stenosis has a relatively large value in systole.

• 한국멀티미디어학회논문지
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• 제18권7호
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• pp.873-885
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• 2015

Today, It is difficult to search the various and numerous information efficiently. For this reason, Semantic Web emerged to provide searching services more easily through the structuring of a variety of unstructured format data and the definition of meaningful relationships between information. Especially, definition of relationship and meaning among resources is significant to share and infer related information. Ontology modeling plays just that role. Weapon parts development information is unstructured and dispersed all over. There are many difficulties in finding desired information, leading to getting improper outcomes. In this paper, we present an intuitive ontology model with weapon parts development information including the multi-dimensional information analysis and expansion of the relevant information. This study build up a ontology model through creating class and hierarchy about parts information and defining the properties of classes with Ontology Development 101[1] procedures using Protégé tools. The ontology model provides users with a platform on which search of needed information can be easy and efficient.

• 통상정보연구
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• 제7권3호
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• pp.159-175
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• 2005

The purpose of the present study is to empirically and theoretically assess the logistics information systems (LIS) success in a quasi-voluntary IS use context. It is important to understand what factors impact the successful use of LIS. The research model is basically based on the framework of IS success proposed by DeLone & McLean(1992) and Seddon(1997). Structural modeling techniques were applied to data collected by questionnaire from 203 LIS users. The results show that user satisfaction play a significant role in influencing the system dependency. The results also revealed that user characteristics is directly affected by perceived usefulness, system quality and information quality, and indirectly influenced by user characteristics.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.713-718
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• 1998

Due to high power ratings and low conduction loss, the IGBT has become more attractive in high power applications. However, its slower characteristics than those of MOSFET cause severe switching losses and switching frequency limitation. This paper proposes the IGBT's soft switching concept with the help of MOSFET, where each of the IGBT and MOSFET plays its role during on-periods and switching instants. Also, the switching losses are analyzed by using the linearized modeling and the modeling and the operations of a converter are investigated to confirm the soft switching of IGBT's.

• 한국경영과학회지
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• 제29권1호
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• pp.127-146
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• 2004

While 'Computer self-efficacy' is widely studied In the social science field with regard to the training effectiveness, little research has focused on clarifying the role of 'needs' in relation to self-efficacy and outcome expectations. in this regard, this study investigated the effects of 'needs to learn computer shills,' extending the social cognitive theory. A survey instrument was adopted and modified from previous studies to measure behavioral modeling, prior experience, Perceived computer self-efficacy, Perceived needs to learn computer skills and outcome expectations. A total of 209 practitioners were surveyed in this study. As a result, most part of the social cognitive theory was again Proven to be effective, and the 'needs to learn computer skills' was proven to be significant as a moderating variable between computer self-efficacy and outcome expectations. Implications of the research were discussed, and further studies were suggested at the end.

• Communications for Statistical Applications and Methods
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• 제13권1호
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• pp.177-190
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• 2006

The aim of this study is to propose a Bayesian model for fitting mortality rate of colon cancer. For the analysis of mortality rate of a disease, factors such as age classes of population and spatial characteristics of the location are very important. The model proposed in this study allows the age class to be a random effect in addition to its conventional role as the covariate of a linear regression, while the spatial factor being a random effect. The model is fitted using Metropolis-Hastings algorithm. Posterior expected predictive deviances, standardized residuals, and residual plots are used for comparison of models. It is found that the proposed model has smaller residuals and better predictive accuracy. Lastly, we described patterns in disease maps for colon cancer.

• Asia pacific journal of information systems
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• 제11권3호
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• pp.149-164
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• 2001

In this paper, an adaptive workflow management system, called K-WFMS, is proposed. The K-WFMS integrates database system and knowledge-based system to automate business processes that are executed with complex and various business rules such as task scheduling, role resolution, and exception handling rules. The K-WFMS is adaptable in the sense that it allows its users to change workflow schema in the course of workflow execution as well as it provides rule-based modeling constructs to handle predictable exceptions during workflow modeling. The overall architecture and implementation of K-WFMS are explained, and the change propagation mechanism to maintain validity of workflow model is suggested.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1999년도 KOBA 방송기술 워크샵 KOBA Broadcasting Technology Workshop
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• pp.11-14
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• 1999

The forthcoming century will be the "era of cyber society" . In a virtual environment, a cyber character plays the role of an agent for the human being. In this paper, we introduce active researches of industries, universities, and research institutes in Korea. After Adam Soft Inc. presented a cyber singer,“Adam”, a few cyber characters have succeeded commercially through Internet, TV, CF, movies and etc. Some universities had their own characters to make fundamental researches in the fields of modeling, motion control, and VR. Research institutes have been funded recently to a cyber character related researches. This paper briefly reviews the recent research works, and future trends in Korea. in Korea.

• 대한공간정보학회지
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• 제10권5호
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• pp.17-28
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• 2002

Time is regarded as an essential feature of land information enabling to track historical landmarks of land uses, ownerships, and taxations based on cadastral maps. Object-oriented temporal modeling helps to simulate and imitate time-varying cadastral data in a chronological and persistent manner. The aim of study is to analyze the role of temporal cadastre tracing footprints of foregoing events in response to various needs and demands associated with historical information of cadastral transactions. In this paper, temporal cadastral object model (TCOM) is proposed to delineate object version history. As an evidence of a new approach and conceptual idea for the importance of temporal cadastre, a part of spatio-temporal processes is illustrated to explain major changes of cadastral map. The feasibility and application of the approach is confirmed by proof-of-concept of temporal cadastre in land information management.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.453-457
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• 2009

Distributed Generation (DG) is predicted to play a important role in electric power system in the near future. insertion of DG system into existing distribution network has great impact on real-time system operation and planning. It is widely accepted that micro turbine generation (MTG) systems are currently attracting lot of attention to meet customers need in the distributed power generation market. In order to investigate the performance of MT generation systems, their efficient modeling is required. This paper presents the modeling and simulation of a MT generation system suitable for isolated operation. The system comprises of a Permanent magnet synchronous generator driven by a MT. A brief description of the overall system is given, and mathematical models for the MT and permanent magnet synchronous generator are presented. Also, the use of power electronics in conditioning the power output of the generating system is demonstrated. Simulation studies with MATLAB/Simulink have been carried out in islanding operation mode of a DG system.