• Transactions of the Korean hydrogen and new energy society
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• v.24 no.3
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• pp.230-236
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• 2013

In this study, successive coating and co-sintering techniques have been used to fabricate LSM/GDC based cathode supported direct carbon fuel cells. The porous LSM/GDC cathode substrate, dense, thin and crack free GDC and ScSZ layers as bi-layer electrolyte, and a porous Ni/ScSZ anode layer was obtained by co-firing at $1400^{\circ}C$. The porous structure of LSM/GDC cathode substrate, after sintering at $1400^{\circ}C$, was obtained due to the presence of GDC phase, which inhibits sintering of LSM because of its higher sintering temperature. The electrochemical characterization of assembled cell was carried out with air as an oxidant and carbon particles in molten carbonate as fuel. The measured open circuit voltages (OCVs) were obtained to be more than 0.99 V, independent of testing temperature. The peak power densities were 116, 195 and $225mWcm^{-2}$ at 750, 800 and $850^{\circ}C$, respectively.

• Journal of Mechanical Science and Technology
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• v.17 no.3
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• pp.440-448
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• 2003

In the present paper, numerical simulations of buoyant plume dispersion in a neutral and stable atmospheric boundary layer have been carride out. A Lagrangian Stochastic Model (LSM) with a Non-Linear Eddy Viscosity Model (NLEVM) for turbulence is used to generate a Reynolds stress field as an input condition of dispersion simulation. A modified plume-rise equation is included in dispersion simulation in order to consider momentum effect in an initial stage of plume rise resulting in an improved prediction by comparing with the experimental data. The LSM is validated by comparing with the prediction of an Eulerian Dispersion Model (EDM) and by the measured results of vertical profiles of mean concentration in the downstream of an elevated source in an atmospheric boundary layer. The LSM predicts accurate results especially in the vicinity of the source where the EDM underestimates the peak concentration by 40% due to inherent limitations of gradient diffusion theory. As a verification study, the LSM simulation of buoyant plume dispersions under a neutral and stable atmospheric condition is compared with a wind-tunnel experiment, which shows good qualitative agreements.

• KSBB Journal
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• v.7 no.2
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• pp.96-101
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• 1992

A low serum medium(LSM) suitable for the growth of a self-constructed hybridoma cell line, KA112, was established by selecting ingredients to replace serum. Insulin and sodium pyruvate was important for the growth of cell line KA112. Various basal media were tested and DMEM gave the most favorable result. Low serum medium (LSM) developed in this work showed cell line stability in the culture for more than 6 months and exhibited cell growth equivalent to that carried out in medium supplemented with 7% FBS. LSM was found to be applicable to the suspension culture of KA112. The reduction of serum level down to 1%(V/V) FBS in LSM resulted in a substantial saving in the cost of media preparation for large scale culture.

• The Transactions of the Korea Information Processing Society
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• v.4 no.12
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• pp.3200-3210
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• 1997

In image processing we encounter some tasks to detect ellipse or to discriminate the curves. LSM is well used to fit curves to ellipse but it can fail to fit correctly when fitting to defected one. To overcome this problem, we propose Modified LSM. Only 2-parameters among 5-paramaters are to be determined by LSM, while 3-parameters are to be calculated by the constrain that the curve must pass 3 given points. Those 3 points are selected by operator so as to have elliptic feature. Such proposed MLSM shows better result than genunal LSM in case when the ellipse is severely defected. and is proved to be good method for determing the human dentition.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.830-837
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• 2010

Since it started the researches on a maglev train on 1960, Germany and Japan arrived to putting to practical use level and accomplished most tests from their test-line. Korea is in progress the preparation for a practical use of low-speed maglev train in 110 [km/h] class and Korea Railroad Research Institute(KRRI) is in progress of a research about core technology of maglev system for high-speed tube train of 700 [km/h] class. In this paper, authors suggest an effective design method of Linear Synchronous Motor(LSM) for high-speed tube train of 700 [km/h] class which has a wound type electro-magnet. Then, authors calculate a variety of properties by changing speed of the LSM model which is designed by a method based on some theoretical equations. Then, authors verify the validity of the method based on some theoretical equations through a verification of property values by Finite Element Method(FEM) analysis method. Finally, in order to design a shape of pole-shoe part of LSM electro-magnet which is hard to design with a basic design method, authors analyze a transition of property values by changing a pole-shoe width and current of the electro-magnet through an analytical method by FEM.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.68-73
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• 2020

This paper proposes an asynchronous circuit design methodology using a new Single Gate Sleep Convention Logic (SG-SCL) with advantages such as low area overhead, low power consumption compared with the conventional null convention logic (NCL) methodologies. The delay-insensitive NCL asynchronous circuits consist of dual-rail structures using {DATA0, DATA1, NULL} encoding which carry a significant area overhead by comparison with single-rail structures. The area overhead can lead to high power consumption. In this paper, the proposed single gate SCL deploys a power gating structure for a new {DATA, SLEEP} encoding to achieve low area overhead and low power consumption maintaining high performance during DATA cycle. In this paper, the proposed methodology has been evaluated by a liquid state machine (LSM) for pattern and digit recognition using FPGA and a 0.18 ㎛ CMOS technology with a supply voltage of 1.8 V. the LSM is a neural network (NN) algorithm similar to a spiking neural network (SNN). The experimental results show that the proposed SG-SCL LSM reduced power consumption by 10% compared to the conventional LSM.

• Journal of the Korean Ceramic Society
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• v.38 no.1
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• pp.93-99
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• 2001

(La,Sr)MnO$_3$(LSM)-YSZ 복합체 양극에 있어서 소결온도 및 전극두께와 cathodic potential이 전극 특성에 미치는 영향을 고찰하였다. 양극의 소결은 삼상계면의 양을 결정하는 중요한 변수로 LSM 단미 양극과 YSZ가 40 wt% 포함된 LSM-YSZ 복합체 양극 모두 120$0^{\circ}C$에 소결했을 때 가장 낮은 분극저항을 나타내었다. 또한 양극 후막의 두께가 얇아지면 양극의 in-plane 저항이 증가하여 ohmic 저항이 증가하였는데, LSM-YSZ 복합체 양극의 경우 약 30$mu extrm{m}$ 정도의 전극두께가 가장 효과적인 전극 특성을 나타내었다. 한편, LSM-YSZ 복합체 양극에 -0.5 V의 cathodic potential을 인가함에 따라 양극에서 일어나는 산소환원반응의 활성이 증가하였는데, 1가 산소이온의 표면확산반응의 분극저항은 감소하였으나, 고주파수 영역에서 나타나는 산소이온전달반응의 저항은 거의 변화하지 않았다. 이것은 Mn의 환원에 의한 양극표면에 생성된 산소공공에 기인한다.

• Atmosphere
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• v.20 no.3
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• pp.319-332
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• 2010

Sensitivity experiments of WRF model using different planetary boundary layer (PBL) and land surface model (LSM) parameterizations are evaluated for prediction of wind fields within the surface layer. The experiments were performed with three PBL schemes (YSU, Pleim, MYJ) in combination with three land surface models (Noah, RUC, Pleim). The WRF model was conducted on a nested grid from 27-km to 1-km horizontal resolution. The simulations validated wind speed and direction at 10 m and 80 m above ground level at a 1-km spatial resolution over the South Korea. Statistical verification results indicate that Pleim and YSU PBL schemes are in good agreement with observations at 10 m above ground level, while the MYJ scheme produced predictions similar to the observed wind speed at 80 m above ground level. LSM comparisons indicate that the RUC model performs best in predicting 10-m and 80-m wind speed. It is found that MYJ (PBL) - RUC (LSM) simulations yielded the best results for wind field in the surface layer. The choice of PBL and LSM parameterization will contribute to more accurate wind predictions for air quality studies and wind power using WRF.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.3
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• pp.85-93
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• 2015

This paper mainly introduces the methods of extracting landslide information using ALOS(Advanced Land Observing Satellite) images and GIS(Geographical Information System) technology. In this study, we classified images using three different methods which are the unsupervised the supervised and the PCA(Principal Components Analysis) for extracting landslide information based on characteristics of ALOS image. From the image classification results, we found out that the quality of classified image extracted with PCA supervised method was superior than the other images extracted with the other methods. But the accuracy of landslide information extracted from this image classification was still very low as the pixels were very similar between the landslide and safety regions. It means that it is really difficult to distinguish those areas with an image classification method alone because the values of pixels between the landslide and other areas were similar, particularly in a region where the landslide and other areas coexist. To solve this problem, we used the LSM(Landslide Susceptibility Map) created with ArcView software through weighted overlay GIS method in the areas. Finally, the developed LSM was applied to the image classification process using the ALOS images. The accuracy of the extracted landslide information was improved after adopting the PCA and LSM methods. Finally, we found that the landslide region in the study area can be calculated and the accuracy can also be improved with the LSM and PCA image classification methods using GIS tools.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.221-222
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• 2012

3대의 인버터를 이용한 루프형 LSM 소형 시험장치의 섹션전환 기법의 모델링 방법에 대한 연구를 수행하였다. 원통형 동기 전동기를 선형 전동기로 변환하여 모델링을 하였다. 3대의 인버터가 교차되어 있는 형태이므로 Section Change시 변하는 역기전력에 따른 Force변화와 Jerk에 대해 시뮬레이션을 통하여 결과를 도출하였다.