• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.542-546
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• 2008

In this study, we developed a whole cardiovascular system model combined with a Laplace heart based on the numerical cardiac cell model and a detailed arterial network structure. The present model incorporates the Laplace heart model and pulmonary model using the lumped parameter model with the distributed arterial system model. The Laplace heart plays a role of the pump consisted of the atrium and ventricle. We applied a cellular contraction model modulated by calcium concentration and action potential in the single cell. The numerical arterial model is based upon a numerical solution of the one-dimensional momentum equations and continuity equation of flow and vessel wall motion in a geometrically accurate branching network of the arterial system including energy losses at bifurcations. For validation of the present method, the computed pressure waves are compared with the existing experimental observations. Using the cell-system-arterial network combined model, the pathophysiological events from cells to arterial network are delineated.

• Water for future
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• v.26 no.4
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• pp.117-125
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• 1993

A flood -flow management system model of river basin has been developed in this study. The system model consists of the observation and telemetering system, the rainfall forecasting and data-bank system, the flood runoff simulation system, the dam operation simulation system, the flood forecasting simulation system and the flood warning system. The Multivariate model(MV) and Meterological-factor regression model(FR) for rainfall forecasting and the Streamflow synthesis and reservoir regulation(SSARR) model for flood runoff simulation have been adopted for the development of a new system model for flood-flow management. These models are calibrated to determine the optimal parameters on the basis of observed rainfall, streamflow and other hydrological data during the past flood periods. The flood-flow management system model with SSARR model(FFMM-SR,FFMM-SR(FR) and FFMM-SR(MV)), in which the integrated operation of dams and rainfall forecasting in the basin are considered, is then suggested and applied for flood-flow management and forecasting. The results of the simulations done at the base stations are analysed and were found to be more accurate and effective in the FFMM-SR and FFMM0-SR(MV).

• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.126-135
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• 1993

Recently, the characteristic of plant production systems in Korea has been changed with the strong trends of integration and large scale, using environmental control techniques. To satisfy this change successfully, first of all, the environmental prediction inside the system must be preceded. While many environmental prediction models for plant production system were developed by many persons, each model cannot be applied to the every situation without the perfect understanding of source codes and the technical modification. The purpose of this study is building the environmental prediction model to predict and evaluate the environment inside the system numerically, and also developing the multipurpose program available for practical design. The model consisted of the basic system model, the cultivation related model and the environmental control related model. The contents of each model are as follows : the basic system model is dealing with thermal and light environments, soil environment and ventilation : the cultivation related model with soil and hydroponic cultures ; and the environmental control related model with thermal curtain and heat exchanging system. The environmental prediction model was developed using a common simulation program, PCSMP, so that it could be easily understood and modified by anyone. Finally, the model was executed and verified through comparison between simulated and measured results for soil culture, and both results showed good agreements.

• Korean Journal of Computational Design and Engineering
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• v.10 no.1
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• pp.49-60
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• 2005

Existing CAD systems have configured geometry data and it is necessary to extend the configured geometry into a knowledge-based system. An intelligent CAD system emerged to provide such a knowledge-based system. However the intelligent CAD system has a limited product model to represent various knowledge models. This paper presents a model, called extended intelligent CAD model, which can extend the product model of the intelligent CAD system into further detailed knowledge model. The extended intelligent CAD model includes a whole design process knowledge and an efficiency of the model has been verified via a knowledge based wiper design system. The model can improve the functionality and efficiency of the existing CAD systems.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.3_4
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• pp.48-60
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• 1995

A flood - flow forecasting system model of river basins has been developed in this study. The system model consists of the data management system(the observation and telemetering system, the rainfall forecasting and data-bank system), the flood runoff simulation system, the reservoir operation simulation system, the flood forecasting simulation system, the flood warning system and the user's menu system. The Multivariate Rainfall Forecasting model, Meteorological factor regression model and Zone expected rainfall model for rainfall forecasting and the Streamflow synthesis and reservoir regulation(SSARR) model for flood runoff simulation have been adopted for the development of a new system model for flood - flow forecasting. These models are calibrated to determine the optimal parameters on the basis of observed rainfall, 7 streamfiow and other hydrological data during the past flood periods.

• Journal of the Korea Safety Management & Science
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• v.7 no.4
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• pp.165-177
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• 2005

Supply Chain Management(SCM) system is a critical investment that can affect future competitiveness and performance of a company. Selection of a right SCM system is one of the critical issues. This paper provides the characteristic factors of SCM system selection and the SCM system evaluation and selection model based on Analytic Hierarchy Process(AHP). The proposed model can systematically construct the objectives of SCM system selection to support the business goals. A empirical example demonstrates the feasibility of the proposed model and the model can help a company to make better decision-making in selecting SCM system.

• Journal of Biosystems Engineering
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• v.12 no.1
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• pp.31-38
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• 1987

In order to improve the traditional post harvest system in Korea, a model for mechanized rice drying and storage system was developed and introduced as the first part of the study(Park, 1986). As the second part of the study, capital requirement and cost of the model system was analyzed. Also, optimum size of the model system was estimated by comparing with the traditional harvest system. From the study, the following results can be concluded: 1. The capital requirement of the model system decreases as the model size increases. For example, a model system having 500 ton storage capacity requires 439,000 Won/ton. However it requires 313,200 Won/ton only, if the model size increases to 1000 ton. 2. Also, total cost of the model system decreases as the model size increases. For example, total costs of the model system having 500 ton and 1000 ton storage capacity are 101,208 Won/ton and 69,320 Won/ton, respectively. 3. The breakeven point (optimum size) of the model can be estimated around 630 ton storage capacity if the operation rate is assumed as 100%. However, the optimum size of the model is 710 ton, if the operation rate it assumed 80%.

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.506-514
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• 2008

This paper presents an intelligent model; named as free model, approach for a closed-loop system identification using input and output data and its application to design a power system stabilizer (PSS). The free model concept is introduced as an alternative intelligent system technique to design a controller for such dynamic system, which is complex, difficult to know, or unknown, with input and output data only, and it does not require the detail knowledge of mathematical model for the system. In the free model, the data used has incremental forms using backward difference operators. The parameters of the free model can be obtained by simultaneous perturbation stochastic approximation (SPSA) method. A linear transformation is introduced to convert the free model into a linear model so that a conventional linear controller design method can be applied. In this paper, the feasibility of the proposed method is demonstrated in a one-machine infinite bus power system. The linear quadratic regulator (LQR) method is applied to the free model to design a PSS for the system, and compared with the conventional PSS. The proposed SPSA-based LQR controller is robust in different loading conditions and system failures such as the outage of a major transmission line or a three phase to ground fault which causes the change of the system structure.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.8-23
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• 2008

The purpose of this study is to develop a Cross Impact System Alternatives Tree(CISAT) model necessary for selecting the interdependent R&D planning system alternatives. This model modifies System Alternatives Tree(SAT) model developed by Kwon et al.. The SAT model is composed of several functions necessary for the achievement of a final goal and several subsystems for satisfying each function. In case that the relationship of technology alternatives is interdependent, this model overlooked a relative importance derived from occurrence or nonoccurrence of the technology alternatives in the future time varience. However, a complex evaluation process within the ballot system is another disadvantage of the SAT. To solve such problems, the Cross Impact Analysis(CIA) model is applied in the SAT model so as to consider the cross impact among interdependent system alternatives.

• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.167-170
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• 2003

In this paper, a design and experiment of PCI Express Core verification Model is described. The model targeting Endpoint core verification is designed by using newly-emerging SystemC which is a system design language based on a new C++ class library and simulation engine. In the verification model, we developed a SystemC Host System model which act as a Root Complex and Device Driver dedicated to the PCI Express Endpoint RTL Core. The test of Host System Model is guided by scenarios which implements and acts point of Device Driver and Root Complex and shows the result of simulation. Also, We present the full structure of verification model and Host model.