• 한국측량학회지
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• 제2권1호
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• pp.34-45
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• 1984

국토의 이용을 극대화하기 위한 지하저장시설의 기초조동에 물리탐사방법중 탄성파측량을 이용하여 지하암반 조건을 규명하고 공동의 위치를 선정할 수 있다. 본 연구에서는 암반의 탄성파속도 및 저속도대의 분포를 분석하여 암반 연약대를 파악하므로써 지하시설물 설치의 타당성 결정에 한 기법을 제시하는데 의의를 두고 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.789-792
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• 2004

This study aims to detect only voids and estimate the cross-sectional size and thickness of voids using radar. A new method based on radar image processing is carried out with various void sizes and depths. The regression relationship between void size which has different depth and the amplitude characteristics of the radar return is considered in a new method of this research. For the purpose of examining; this regression relationship, experiments with change of void depth, surface area and thickness were carried out. Finally, the threshold value for image processing which aims to represent only voids to be fitted size (width) can be obtained. As the results, a proposed method in this study has a possibility of detecting only voids and estimating void size and thickness with good accuracy.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.1171-1178
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• 2005

근래에 이르러 인도네시아의 지진해일 때 수많은 사상자가 나오고, 일본근해의 지진의 영향으로 우리나라에도 영향을 미쳤다. 이에 따라, 지진에 대한 대비와 지진이 발생하였을 때의 신속한 정보전달이 중요한 요인이 되었다. 따라서 지진을 감지한 관측지에서 지진의 영향이 우려되는 지역으로의 신속한 정보 전달체계를 확립하고, 더 나은 지진 관측 장비를 개발함으로써, 지진피해로 인한 시민의 재산과 생명의 손실을 최소화 하는데 이바지 하고자 한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권4호
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• pp.174-180
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• 2005

Linear pulse motor (LPM) has the vibration during the operation because of magnetic characteristic which is caused by the mechanical configuration and the electromagnetic property. This paper proposes the calculation of thrust on the base of magnetic equivalent circuit for the purpose of the vibration minimization of LPM. The permeance of LPM is calculated and simulated from the construction tooth. The thrust is compared with the analytical method, the 3D finite element method (FEM) and the experimental values. The vibration of LPM is measured and estimated to select the input current wave for an optimal operation condition.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.267-270
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• 2000

This paper describes measurement of relative permittivity of illite found in young-dong area. A measurement of relative permittivity of illite used to cylindrical cavity resonators with moveable cap. A concentric dielectric-rod inserted cylindrical cavity resonator and an exact field representation of travelling wave mode are introduced for measurement of relative permittivity. The exact electromagnetic fields in cylindrical cavity with concentric dielectric rod is analysed. A relative permittivity of dielectric in cavity is calculated by analyzing the characteristic equation. The characteristic equation is solved by using the ContourPlot graph of Mathematica. We know that the field representation of travelling mode is exact. As a result, relative permittivity of dielectric materials were 7.820 at sample-1 and 7.894 at sample-2.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.349-353
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• 1999

In this paper, to fabricate the AC power electroluminescent device (PELD) with high brightness, new structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material were BaTiO3 and ZnS:Cu respectively. Fabricated AC power EL devices were estimated by optical and electrical properties of EL spectrum, brightness, CIE coordinate system, transferred charge density and EL emission wave in time domain. With above results, we found that brightness of newly proposed AC powder EL power EL device was 2754 cd/m2 at 100V, 400 Hz and compared with conventional device structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.3246-3248
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• 1999

The APC is a coding algorithm which has the middle property of both Wave Coding(ex ADPCM) and Vocoding(ex CELP) and can decode a proper quality of sound by using scalar quantizer instead of vector quantizer at computation a low calculation. So, the APC required for Voice Codec of INMARSAT-B could be successfully implemented by full duplex using TMS32OC30(DSP).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.57-60
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• 2003

This paper describes the modeling and simulation results for film bulk acoustic resonators(FBAR). We present the frequency tuning mechanisms, analytical solutions of the wave equation and the influence of the thickness of the electrodes. The impedance for PZT based FBAR is derived utilizing proper boundary conditions and their material parameters. Ferroelectrics-based RF filter composed of FBARs are designed.

• 센서학회지
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• 제15권4호
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• pp.263-268
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• 2006

We have demonstrated a highly sensitive temperature sensor using an etched single mode fiber with a thermally expanded core region. Large core size of thermally expanded core facilitates access to evanescent wave by the wet etching. The etched region was surrounded by a low dispersive external medium with high thermo-optic coefficient. Due to the large difference between the dispersion property of the fiber and that of the external medium, the device reveals a cut-off properties at spectral region. The cut-off wavelength was shifted by the variations of the environmental temperatures because of thermo-optic effect of the external medium. The sensitivity of the fabricated device was found to be $45nm/^{\circ}C$.

• 전기학회논문지
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• 제58권11호
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• pp.2242-2246
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• 2009

In this paper, a homogeneous dual composite right/left-handed (D-CRLH) transmission line (TL) is proposed by using a defected ground structure (DGS) on the ground plane. In order to satisfy a homogeneity condition of metamaterial, a subwavelength unit cell is designed by way of a spiral DGS and a meander stub. From a dispersion diagram, it is expected that the frequency bands for the left-handed (LH) property is 3.5 - 4.4 GHz. At 3.8 GHz in the LH band, backward propagating phenomenon is observed from full-wave analysis. The experimental results show that the proposed TL has a stop-band in 1.75 - 3.6 GHz.