• 한국지진공학회논문집
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• 제14권5호
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• pp.53-64
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• 2010

구조물의 지진취약도 곡선은 지진의 다양한 강도를 최대지반가속도 등의 함수로 하여 몇 가지로 구분된 손상상태를 초과할 확률을 나타내는 것으로 구조물의 내진성능과 지진위험도를 평가하는데 유용하게 활용된다. 기존의 많은 연구자들이 수행한 지진취약도 곡선에 대한 연구에서 근거리 및 원거리 지진하중의 특성에 대하여 고려하지 못하였다. 본 연구에서는 근거리 및 원거리 지진으로 구분되는 지진가속도 기록을 사용하여 국내 교량의 대표적인 형식의 하나인 PSC상자형교에 대한 지진취약도 곡선을 평가하였으며 근거리와 원거리로 구분된 지진 특성이 지진취약도 곡선에 미치는 영향을 분석하였다. 예제교량의 지진취약도 곡선에 대한 근거리 및 원거리 지진의 영향이 현저한 차이를 나타내므로 지진취약도 해석시 근거리와 원거리로 구분되는 지진의 특성을 반영하여야 할 것이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.487-491
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• 2004

For tile hydrogeological data of the National Groundwater Monitoring Wells(NGMW), a statistical analysis is made to reveal aquifer characteristics of the country. Results of the pumping and recovery test are classified into 4～5 types by the pattern of drawdown and residual drawdown curves. The analysis of aquifer characteristics shows that the hydraulic conductivity of alluvial aquifers is greater than that of fractured-rock aquifers. The hydraulic conductivity of alluvial aquifers slightly increases as the distance to the discharge area decreases. 77.5% of the NGMWs, where the distance to the discharge area is more than 100m, shows the constant head boundary. This result suggests that the fractured and the alluvial aquifers are fairly interconnected, and water can be supplied from one aquifer to tile other where pumping tests are performed. It is analyzed that the wells showing the impermeable boundary are influenced by small scale of aquifers, poor aquifer transmissivities, and impermeable layers.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.13-16
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• 1998

An anomalous current characteristics which show the superposition of a low current level and high current level at the subthreshold region when SONOSFETs are in memory states were investigated. We have assumed this phenomena were resulted from the effect of parasitic transistors by LOCOS isolation and were modeled to a parallel equivalent circuit of one memory transistor and two parasitic transistors. Theoretical curves are well fitted in measured log I$_{D}$-V$_{G}$ curves independent of channel width of memory devices. The difference between low current level and high current level is apparently decreased with decrease of channel width of devices because parasitic devices dominantly contribute to the current conduction with decrease of channel width of memory devices. As a result, we concluded that the LOCOS isolation has to selectively adopt in the design of process for charge-trap type NVSM.VSM.

• 한국초전도ㆍ저온공학회논문지
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• 제1권2호
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• pp.30-36
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• 1999

Superconductors are dissipative when exposed to time-varying magnetic fields. To analyze the AC characteristics of a superconductor, one usually needs to know magnetization curves of it. Good magnetization curves can be obtained only in homogeneous magnetic filed. In This paper, we report the setup and test results of a magnetization measurement system, which consists mainly of frequency-variable power supply and homeogenous magnet with 7-cm long air gap. Special emphasis are foused on the design and fabrication of the magnet, which aims to give background magnetic fields, and on the overall characteristics of the system.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.98-106
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• 2001

The deformation characteristics of cohesionless soils in Korea were investigated using resonant column tests. Total 60 samples, which were sampled from sedimentary and residual soils and reconstituted using controlled particle-size distributions, were prepared. The confining pressure applied in the tests ranges from 20 kPa to 500 kPa. The test results ware categorized into 3 groups including clean sands, silt and silty sand, and residual soils. Based on test results, the small-strain shear modulus(G$_{max}$) and damping ratio(D$_{min}$) were determined and the effects of confinement on G$_{max}$ and D$_{max}$ were characterized. The empirical correlations predicting G$_{max}$ were suggested for 3 group soils. Nonlinear deformational characteristics of clean sands are significantly affected by confining pressure and the ranges and mean curves for G and D are suggested considering the range of confining Pressure. The silt and silty sand and residual soils were weakly affected by confining pressure, so the representative ranges and curves, independent of confining pressure, were proposed.d.posed.d.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.238-240
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• 2008

This paper gives a basic data of the breakdown characteristics of Dry-Air and air based on their dew point and humidity variations in experimental GIS model by applying AC voltage. The breakdown voltage of Dry-Air was increased as gap length had been increased. The characteristics of Dry-air which had low dew point were higher. In the case of air, the breakdown voltage curves were like Dry-Air' s. But the curves were slightly folded up and down because of impurities.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.813-819
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• 2008

For the wear characteristics assessment of Saemaul train passing through curves, an analysis model for multi-car system has been developed. By using this model and ADAMS/Rail, sensitivity analyses have been conducted for the wear characteristics by changing the related parameters. According to the increase of running speed, the wear number, the sliding mean and friction coefficient were increased. At high speed, the wear number, the sliding mean and friction coefficient of left wheel showed higher than right wheel. If the cant increased, the wear number the sliding mean and friction coefficient increased. but decreased based on the balance cant value by the curvature and running speed.

• 전자공학회논문지A
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• 제30A권4호
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• pp.40-50
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• 1993

In this paper, MODFET devices with various gate length are simulated using the Monte-Carlo method. The number of superparticle is 5000 and the Poisson equation is solved to obtain field distribution. The structure of MODFET is n-AlGaAs/i-AlGaAs/iGaAs and doping concentration of n-AlGaAs layer is 1${\times}10^{17}/cm^{3}$ and the thickness is 500.angs., and the thickness of i-AlGaAs is 50$\AA$. The devices with gate length 0.2$\mu$m, 0.5$\mu$m, 1.0$\mu$m respctively are simulated and the current-voltage curves and transport characteristics of that devices are obtained. Occupancy of each subband and electron energy distribution and conduction energy band in channel have been analyzed to obtain transport characteristics, and particles transposed from source to drain have been analyzed to current-voltage curves. Current level is highest for the device of Lg=0.2$\mu$m and transconductance of this device is 310mS/mm.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.307-310
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• 1999

In this panel test, the toughness and post-cracking tensile strength of SFRC(Steel Fiber Reinforced Concrete) measured on 24 panels(size; 60cm $\times$ 60cm $\times$ 10cm) which are the basic characteristics than can determine the load bearing capacity of SFRC are investigated. Those values are calculated using load-deflection curves and load-absorbed energy curves. Post-cracking tensile strength of SFRC in this study are determined by yield line theory. From the test results, it is seen that the higher the volume of steel fiber is, the higher the absorbed energy is.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2000년도 춘계정기학술대회 e-Business를 위한 지능형 정보기술 / 한국지능정보시스템학회
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• pp.475-478
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• 2000

Recently encryption algorithms based on difficulties of factorization have been used with popularization. Prime number factorizations are progressed rapidly. In this paper, characteristics of elliptic curve are analyzed and generation of elliptic curves suitable for prime number factorization is discussed.