• Nuclear Engineering and Technology
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• v.37 no.1
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• pp.101-108
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• 2005

The neutron induced nuclear cross-section data for Pd-105, Ag-109, Xe-131, and Cs-133 were calculated and evaluated from an unresolved energy to 20 MeV. The energy dependent optical model potential parameters were extracted based on recent experimental data and applied up to 20 MeV. A spherical optical model and a statistical model for the equilibrium energy, and a multistep direct and a multistep compound model for the pre-equilibrium energy were used in the calculation. The direct capture model was recently introduced for fast neutron capture. The theoretically calculated cross-sections were compared with the experimental data and the evaluated files. The total and capture cross-sections calculated using the model were in good agreement with the reference experimental data. The evaluated cross-section results were compiled in ENDF-6 format and merged with the resonance component, already adopted in the ENDF/B-VI release 8. New data library files covering from thermal to 20 MeV were created. They are at the preliminary stage of an ENDF/B- VII release.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.47-50
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• 2006

An active contour model has been used to detect the edges in a still image. In order to apply the active contour model to edge detection, the energy function which consists of internal, external and image energies should be defined. After defining the energy function, the edge of an object is detected through minimization of the value of the energy function. In this paper, the modified internal energy function is proposed to improve the convergence of the energy function when the active contour model is applied to the tracking of deformable objects using the greedy algorithm. In order to show the performance of the proposed energy function, experiments were carried out for the still and animated images.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.17-23
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• 2004

In the present work, the numerical model was refined to predict the thermal analysis of energy storage in a fixed beds during (charging ,storing, discharging) mode. The governing energy equations of both fluid and the solid particles along with their initial and boundary conditions are derived using a two-phase, one dimensional model. The refined model is carried out by taking into account change of (air density , air specific heat) with air temperature and also by taking into considerations heat losses from bed to surrounding. Finite difference method was used to obtain solution of two governing energy equations of both fluid and solid particles through a computer program especially constructed for this purpose. The temperature field for the air and the solid are obtained, also efficiency of energy stored inside the bed is computed. Finally using refined model the effect of air flow rate per unit area Ga (0.2, 0.3, and 0.4 kg/$m^2$-s), and inlet air temperature (200, 250, 300 $^{\circ}C$) on energy storage characteristics was studied in three mode ( charging ,storing, discharging). The rock particles of diameter 1 em is used as bed material in this research.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.1
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• pp.16-21
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• 2018

This work aims to develop a platform to investigate the effect of operation schedules on the building energy consumption and to derive a simulation model based optimal start and stop daily strategy. An open-source building energy simulation tool DOE2 is used for the engine, and the developed simulation model is validated using ASHRAE guideline 14. The effect of late-start/early-stop operation of HVAC system on the daily building energy consumption was analyzed using the developed simulation model. It was found that about 10% of energy consumption cut was possible using the control strategy for an hour of advance of the stop operation, and about 3% per an hour of delay of the start operation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6799-6806
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• 2015

Electric energy consumption is always followed by the introduction of diversity scale-up and state-of-the-art equipments in logistic centers. In order to analyze the status and the characteristic of the electric energy consumption quantitatively, and also to evaluate the efficiency of the electric energy, this research aims to develop an estimation model of standard electric energy consumption for logistic centers. The proposed model applies the thermodynamics theory so as to effectively reflect the peculiarity that the temperature in the logistic center influences the electric energy consumption. And the model consists of the energy consumed by the refrigerator, which can be subdivided into the heat conducted through the wall, the heat convected by the open doors and the heat lost into the goods, and the electric consumption of the machinery equipments. The model also includes a variety of explanatory variables to support an operator of logistics centers in evaluating the efficiency of energy consumption and establishing improvement strategies for energy efficiency. Application of the model developed in this study is discussed with observed data on energy consumption of a logistics center.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.679-680
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• 2011

This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.11a
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• pp.69-76
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• 2001

The coal gasification process of a slurry feed type, entrained-flow coal gasifier was numerically predicted in this paper. By divding the complicated coal gasification process into several simplified stages suh as slurry evaporation, coal devolitilisation and two-phase reactions coupled with turbulent flow and two-phase heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. The k-$\varepsilon$turbulence model was used for the gas phase flow while the Random-trajectory model was applied to describe the behavior of the coal slurry particles. The unreacted-core shrinking model and modified Eddy Break-Up(EBU) model were used to simulate the heterogeneous and homogeneous reactions, respectively. The simulation results obtained the detailed informations about the flow field, temperature inside the gasifier. Meanwhile, the simulation results were compared with the experimental data as function of $O_2$/coal ratio. It illustrated that the calculated carbon conversions agreed with the measured ones and that the measurd quality of the atngas was better than the calculated one when the $O_2$/coal ratio increases. The result was related with the total heat loss through the gasifier and uncertain kinetics for the heterogeneous reactions.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.71-77
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• 2009

A theoretical model of multiple cracking failure mechanism is proposed herein for fiber reinforced high performance Cementitious composites. By introducing partial debonding energy dissipation on non-first cracking plane and fiber reinforcing parameter, the failure mechanism model of multiple cracking is established based on the equilibrium assumption of total energy dissipation on the first crack plane and non-first cracking plane. Based on the assumption of the first crack to be the final failure crack, energy dissipation terms including complete debonding energy, partial debonding energy, strain energy of steel fiber, frictional energy, and matrix fracture energy have been modified and simplified. By comparing multiple cracking number and energy dissipations with experiment results of the reference's data, it indicates that this model can describe the multiple cracking behavior of fiber reinforced high performance cementitious composites and the influence of the partial debonding term on energy dissipation is significant. The model proposed may lay a foundation for the predictions of the first cracking capacity and post cracking capacity of fiber reinforced high performance cementitious composites and also can be a reference for optimal mixture for construction cost.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.579-585
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• 1996

A CATHENA model for the reactor regulating system is developed and tested independently. A CATHENA plant model is created by combining this model with the reference CATHENA model which has been developed to analyze a loss-of-coolant accident (LOCA) for the Wolsong 2 generating station. This model is intended to provide a trip coverage analysis capability. The CATHENA reactor regulating system model includes the demand power routine. the light water zone control absorbers, mechanical control absorbers and adjusters. The CATHENA model is tested for steady state at 103% full power. A postulated accident transient (small LOCA) was also tested. The results show that the control routines in CATHENA were set up properly.

• Nuclear Engineering and Technology
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• v.36 no.2
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• pp.165-174
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• 2004

The distributed resistance model has been recently implemented into the MATRA-LMR code in order to improve its prediction capability over the wire-wrap model for a flow blockage analysis in the LMR. The code capability has been investigated using experimental data observed in the FFM (Fuel Failure Mock-up)-2A and 5B for two typical flow conditions in a blocked channel. The predicted results by the MATRA-LMR with a distributed resistance model agreed well with the experimental data for wire-wrapped subchannels. However, it is suggested that the parameter n in the distributed resistance model needs to be calibrated accurately for a reasonable prediction of the temperature field under a low flow condition. Finally, the analyses of a blockage for the assembly of the KALIMER design are performed. Satisfactory results by the MATRA-LMR code were obtained through and rerified a comparison with results of the SABRE code.