• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.101-110
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• 2002

This article summarises the traditional method of soil-structure interaction based on the modulus of subgrade reaction and shows its weakness. In order to avoid these weakness, a new soil-structure interaction model is proposed. This model considers the soil as a set of connected springs which enables interaction between springs. Its use is as simple as the traditional model but allows to define the soil properties independently from the structural properties and the loading conditions. Thus, the definition of the modulus of subgrade reaction is unnecessary as each component is defined by its own modulii (Young's modulus and shear modulus). The non-linear soil behaviour for the shear stress versus distortion is also incorporated in the model. This feature allows to pinpoint the arching effect in the ground and shows how the stresses concentrate on stiff materials. Based on these principles, three dimensional program has been developed in order to solve the difficult problem of soil improvement by inclusions (stiff or soft). Also the possibility to take into account a flexible mat and/or a subgrade layer has been implemented. Equations used in the model are developed and a parametric study of the necessary data used in the program is presented. In particular, the Westergaard modulus notion and the arching effect are analysed.

• Journal of Environmental Science International
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• v.17 no.6
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• pp.689-698
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• 2008

Numerical study is conducted to predict effects of radiative heat loss and fuel composition in synthetic gas diffusion flame diluted with $CO_2$. The existing reaction models in synthetic gas flames diluted with $CO_2$ are evaluated. Numerical simulations with and without gas radiation, based on an optical thin model, are also performed to concrete impacts on effects of radiative heat loss in flame characteristics. Importantly contributing reaction steps to heat release rate are compared for synthetic gas flames with and without $CO_2$ dilution. It is also addressed that the composition of synthetic gas mixtures and their radiative heat losses through the addition of $CO_2$ modify the reaction pathways of oxidation diluted with $CO_2$.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.165-170
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• 1998

Lipase-catalyzed esterification of n-butyl oleate was carried out in n-hexane as a model reaction. The optimal activity of Candida rugosa lipase was shown in a water activity ($a_w$) range of 0.52 to 0.65 at $30^{\circ}C$. The water produced from the esterification was removed by a tubular type pervaporation system. The rate of ester formed from the enzymatic esterification was allowed to be the same as the rate of water removal by maintaining an optimal $a_w$ of the reaction system using an on-off dewatering control device. The reaction rate and yield with a$a_w$ control were increased two folds higher than the respective values for the uncontrolled reaction.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.589-594
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• 1993

This paper presents a fault detection strategy that discriminates the faulty sensor and that detects the component fault using a bank of observers for the system in which sensor fault and component fault can occur simultaneously. Observers as many as the number of measurements are designed, and each observer uses measurements excluding sequentially one measurement, to estimate the state variables. The faulty sensor can be found out by comparing each state variable from different observer. Next, component fault can be detected by using measurements from the sensors excluding the faulty sensor. The suggested strategy is applied to a nonisothermal, series reaction with unknown reaction kinetics in a CSTR. This strategy is found out to perform well even in the case that the sensor and component fault occur simultaneously. Since each observer is designed to be independent of reaction kinetics, this strategy is not affected by the model uncertainty and nonlinearity of the reaction kinetics.

• Journal of the Korean Ceramic Society
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• v.21 no.1
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• pp.60-66
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• 1984

During the metallization in the manufacturing of the ceramic capacitor at the boundary layer between Pd or Pt electrode and $BaTiO_3$-dielectric reactions were analysed. For the study of the reaction Electron Spin Resonance (ESR) Method was used. With the aid of ESR an increased of the concentration of the paramagnetic $Ti^{3+}$-Centers on the metallizing process could be seen. It meaned a reduction effect although the metallization was accomplished under oxidation atmosphere. Therefore it could be regarded as a reaction at the boundary layer. In order to investigate the reaction ad double octahedral model was compared and the increase of the $Ti^{3+}$-concentration was studied.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.161-167
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• 2002

Cai-go management facility of harbor are required an expansion due to increase of cargo quantity. Design technology of Yard AGV call be possible to deal many cargo rapidly and accurately. So it is produced a profit about cal-go management. This study is presented optimum of suspension parameter for design technology Yard AGV. Model I, II are modeled about Initial of container weight, height. When the maximum stroke of suspension is 0.26m, optimum is achieved to reduce the reaction force at the minimum. Also, the reaction force is study to become stability in I second. A change of spring constant and coefficient of damper make change the reaction force and minimum reaction force appear in optimum value. All modeling and analysis are used combination. contact element of Ansys program.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.287-298
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• 2003

A numerical investigation of a catalytically stabilized thermal (CST) combustor was conducted for a multi-channel catalyst bed, and both the catalyst bed and thermal combustor were simultaneously modeled. The numerical model handled the coupling of the surface and gas reaction in the catalyst bed as well as the gas reaction in the thermal combustor. The behavior of the catalyst bed was investigated at a variety of operating conditions, and location of the flame in the CST combustor was investigated via an analysis of the distribution of CO concentration. Through parametric analyses of the flame position, it was possible to derive a criterion to determine whether the flame is present in the catalyst bed or the thermal combustor for a given inlet condition. The results showed that the maximum inlet temperature at which the flame is located in the thermal combustor increased with increasing inlet velocity.

• Journal of Environmental Science International
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• v.23 no.4
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• pp.615-623
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• 2014

The groundwater level varies according to the characteristics and composite materials of aquifer. In this study, specific yield and reaction factor which are the major two hydrogeological parameters in the WTF(Water Table Fluctuation) method were estimated and analyzed spatial characteristics. 8 groundwater level stations which have enough measuring period and high correlation with rainfall in the Hancheon watershed were used. The results showed that specific yield was randomly distributed and reaction factor showed inverse trend with altitude. If the enough data were collected, reaction factor according to altitude in ungauged points could be estimated by using these parameter characteristics.

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1247-1254
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• 2018

We study the uncertainty stemming from different theoretical models in the spectroscopic factors extracted from experiments. We use three theoretical approaches, the distorted wave Born approximation (DWBA), the adiabatic distorted wave approximation (ADWA) and the continuum discretized coupled-channels method (CDCC), and analyze the $^{12}C(d,p)^{13}C$, $^{14}C(d,p)^{15}C$ reactions. We find that the uncertainty associated with the adopted theoretical models is less than 20%. We also investigate the contribution from the remnant term and observe that it gives less than 10% uncertainty. We finally make an attempt to explain the discrepancy in the spectroscopic factors of $^{17}C(\frac{3}{2}^+)$ between the ones extracted from experiments and from shell model calculations by analyzing the $^{16}C(d,p)^{17}C$ reaction.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.05a
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• pp.94-97
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• 2003

본 연구에서는 반도체제조에 필수적으로 사용되는 플라즈마장비의 성능을 예측.분석하여 개발 시간 및 비용의 절감과 장비의 성능을 극대화 할 수 있도록 이론적 전산모사 환경(VIP-SEPCAD)을 개발하고 있다. VIP-SEPCAD는 플라즈마의 물리.화학적 특성을 예측하는 plasma model, 중성화학종들의 반응 및 유돈 특성을 예측하는 neutral reaction-transport model, particle의 유동 특성을 예측하는 particle transport model, particle의 생성 및 성장 특성을 예측하는 particle formation-growth model, 식각 또는 증착되는 웨이퍼 표면변화를 예측하는 surface evolution model로 구성되어 있다. 현재 개발된 VIP-SEPCAD를 이용하여 산소 플라즈마의 특성과 각종 화학성분들의 분포를 예측하고 particle의 거동에 대하여 분석하였다.