• 한국재료학회지
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• 제15권10호
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• pp.657-661
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• 2005

[ $ZnHgGa_4Se_8\;and\;ZnHgGa_4Se_8::Co^{2+}$ ] single crystals were grown by the Bridgman-Stockbarger method. The single crystals crystallized into a defect chalcopyrite structure. The optical energy band gap of the single crystals was investigated in the temperature range 11-300K. The optical energy band gap of the $ZnHgGa_4Se_8:Co^{2+}$ single crystal was smaller than that of the $ZnHgGa_4Se_8$ single crystal. The temperature dependence of the optical energy band gap of the single crystals was well fitted by the Varshni equqtion. The impurity optical absorption spectrum of the $ZnHgGa_4Se_8:Co^{2+}$ single crystal was measured in the wavelength region 300-2300 m at 80 K. Impurity absorption peaks in the spectrum were analyzed within the framework of the crystal field theory and were attributed to the electron transitions between the energy levels of $Co^{2+}$ sited in the Td symmetry point.

• 한국지진공학회논문집
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• 제6권2호
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• pp.1-7
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• 2002

본 연구에서는 구조물의 설계방법에 국한되어 있는 직접 변위설계법을 응용하여 기존 구조물의 성능점을 산정하는 방법에 관하여 연구하였다. 개발된 방법을 이용하여 단자유도 구조물의 주기, 항복 후 강성비, 요구되는 탄성강도에 대한 항복강도비 등의 설계변수를 변화시키며, 지진 하중에 대한 응답을 구하고 그 결과를 분석하였다. 또한 10층 철골 골조의 내진성능 평가에 적용하였다. 제안된 방법의 정확성을 검증하기 위하여 기존의 내진성능 평가방법인 능력스펙트럼법과 시간이력해석법에 의한 결과와 비교하였다. 제안된 방법은 능력스펙트럼법과 동일한 결과를 보였으며 시간이력해석 결과와도 비교적 잘 일치하였다.

• 소음진동
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• 제8권5호
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• pp.957-963
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• 1998

A new signal processing technique, the directional harmonic wavelet map(dHWM), is presented to characterize the instantaneous planar motion of a measurement point in a structure from its transient complex-valued vibration signal. It is proven that the directional auto-HWM essentially tracks the shape and directively of the instantaneous planar motion, whereas the phase of the directional cross-HWM indicates its inclination angle. Finally, the technique is suessfully applied to an automobile engine for characterization of its transient motion during crank-on/idling/engine-off.

• 천문학논총
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• 제19권1호
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• pp.1-10
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• 2004

On the framework of a linearly perturbed Friedmann-Robertson-Walker spacetime, we derive an expression for the cosmological angular diameter distance affected by scalar and tensor perturbations. Our expression is applicable in linear order to distances in general FRW models. We study the effect of a stocastic gravitaional wave background on the two-point correlation function of the angular diameter distance fluctuations and, on the basis of this we also derive an expression for the power spectrum of the angular diameter distance fluctuations.

• 생약학회지
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• 제7권3호
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• pp.209-210
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• 1976

To identify eriodictyol from the leaves of Lespedeza maximowiczii C.K. $S_{CHNEIDER}$, growing in Korea, the fresh leaves collected at Mt. Chil Bo, Geong Gi Province were used in the investigation. A white crystal was isolated from the water extract and it was identified as eriodictyol by its melting point, physico-chemical properties, thin layer chromatography and infrared absorption spectrum patterns.

• 대한수학회논문집
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• 제16권3호
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• pp.437-443
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• 2001

In this paper the inverse problems for the Dirac Operator are studied. A set of values of eigenfunctions in some internal point and spectrum are taken as a data. Uniqueness theorems are obtained. The approach that was used in the investigation of inverse problems for interior spectral data of the Sturm-Liouville operator is employed.

• Elastomers and Composites
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• 제52권3호
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• pp.194-200
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• 2017

After the grafting of methacrylic acid (MA) to ethylene propylene diene monomer (EPDM), a new peak at $1704cm^{-1}$ corresponding to the carboxylic acid group was observed in the infrared (IR) spectrum. This characteristic MA molecule peak grew larger as the MA contents were increased. After casting films were prepared from pure EPDM and MA-grafted EPDM, differential scanning calorimeter (DSC) measurements were made the pure EPDM exhibited a melting point of approximately $45^{\circ}C$ while that of the MA-grafted EPDM was $135{\sim}140^{\circ}C$. As the graft ratio of MA increased, the absorbed heat capacity increased at temperatures near $135{\sim}140^{\circ}C$, indicating that an increased amount of MA reacted. Furthermore, owing to the addition of crystalline MA, it is expected that strength of the elastomer will improve as the graft ratio increases, as a result of the increased number of hard segments.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2177-2185
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• 2015

Breast cancer is the most common malignancy in women around the world. About one in 12 women in the West develop breast cancer at some point in life. It is estimated that 5%-10% of all breast cancer cases in women are linked to hereditary susceptibility due to mutations in autosomal dominant genes. The two key players associated with high breast cancer risk are mutations in BRCA 1 and BRCA 2. Another highly important mutation can occur in TP53 resulting in a triple negative breast cancer. However, the great majority of breast cancer cases are not related to a mutated gene of high penetrance, but to genes of low penetrance such as CHEK2, CDH1, NBS1, RAD50, BRIP1 and PALB2, which are frequently mutated in the general population. In this review, we discuss the entire spectrum of mutations which are associated with breast cancer.

• 대한수학회보
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• 제57권4호
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• pp.909-919
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• 2020

The 4-dimensional solvable Lie group Sol₀⁴ does not admit a lattice. The purpose of this paper is two-fold. We study poly-crystallographic groups of Sol₀⁴, and then we study Nielsen fixed point theory on the spaces modeled on Sol₀⁴.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.111-116
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• 2001

This paper introduces how to adopt the X-12-ARIMA to decompose the railway passenger demand of the Korea National Railroad Especially, selecting on proper filters is focused. The trend filter is identical to the low pass filter in the signal Processing field, and so the seasonal filter is to band pass filter too. Some considerations, selecting a filter, are provided from the view-point of the spectrum analysis. The technique introduced in this paper will be adopted to the project that is to develope the forecasting system of Korea railway passenger demand which is a part of the high speed rail information system.