• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.459-463
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• 1997

핵의학적 유방영상법은 오랜동안 시범되어 왔지만 임상에서 큰 역할을 못했고, 근래에 핵의약품과 핵의학기기 사용방법의 발전으로 scintimammogram(SM)이 다시 각광을 받게 되었다. 유방암 진단에 대한 핵의학영상법의 특이도와 예민도가 방사선 유방촬영법보다 높다고 보고되었으나 1cm보다 작은 유방암은 SM에 용이하게 발견되지 않는다. 본 보고에서는 1cm보다 작은 유방암이 발견된 두 증례를 발표한다. 한증례는 $^{99m}Tc$ MDP를 수술전 골영상을 위해서 사용하였고, 두 번째 증례는 비촉지 유방종괴를 $^{99m}Tc$ MIBI로 유방촬영 하였다.

• Geophysics and Geophysical Exploration
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• v.12 no.1
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• pp.99-104
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• 2009

We propose a waveform inversion method for SH-wave data obtained in a shallow seismic refraction survey, to determine a 2D inhomogeneous S-wave profile of shallow soils. In this method, a 2.5D equation is used to simulate SH-wave propagation in 2D media. The equation is solved with the staggered grid finite-difference approximation to the 4th-order in space and 2nd-order in time, to compute a synthetic wave. The misfit, defined using differences between calculated and observed waveforms, is minimised with a hybrid heuristic search method. We parameterise a 2D subsurface structural model with blocks with different depth boundaries, and S-wave velocities in each block. Numerical experiments were conducted using synthetic SH-wave data with white noise for a model having a blind layer and irregular interfaces. We could reconstruct a structure including a blind layer with reasonable computation time from surface seismic refraction data.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1843-1845
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• 2002

유입식변압기 내부고장의 조기발견을 위하여 유중가스분석법이 가장 일반적으로 사용되고 있다. 본 연구에서는 변압기 내부이상의 종류에 따른 발생가스의 특성과 유중가스분석법으로 사용되고 있는 key gas법 Donenburg법, Rosers법, IEC법에 대한 특성을 비교분석하였다. 동일한 가스성분에 의해서도 각 진단법이 의한 진단결과가 다르고, 또한 진단결과가 발생하지 않는 경우가 발생하고 있으며, 고장원인이 2가지 이상으로 복합되어 있는 경우 모든 고장원인을 밝혀낼 수 없는 것으로 나타났다.

• 건강소식
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• v.18 no.9 s.190
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• pp.14-17
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• 1994

• 지반과기술
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• v.8 no.3
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• pp.39-42
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• 2011

• Journal of Welding and Joining
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• v.20 no.4
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• pp.451-458
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• 2002

플라즈마 용사법에 의한 섬유강화 복합 소재를 개발하면서 독특한 미세구조가 발견되었다. 이러한 형상은 코팅의 물리적 특성과 직접적으로 관련이 있다고 사료된다 섬유강화 코팅의 구조를 밝히기 위해 고배율 전자현미경이 사용되었으며 분석을 통해 일반적 용사코팅 의 미세구조가 내부에 투입된 강화 섬유(FIBER 또는 WHISKER)에 의해 변형되며 열적으로 anisotropic한 상태로 되었음을 보여주었다.

• Journal of the Korean Chemical Society
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• v.47 no.5
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• pp.460-465
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• 2003

Structural alteration of p53 and overexpression of p53 protein are the most common genetic abnormalities in various kinds of human cancer. Mutations in the p53 tumor-suppressor gene are usually associated with an advanced development of colorectal cancer characterized by the transition from the adenoma to carcinoma stage. Mutations in exons 5-8 of the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) and denaturing high performance liquid chromatography(DHPLC). SSCP analysis detected 7 mutations(C13109>T) in 50 colorectal cancer samples(14%) at exon 5, and DHPLC analysis detected 7 mutations (C13109>T) and 2 mutation(C13202>A, C13204>G) in 50 colorectal cancer samples(18%) at exon 5. All of 9 mutations were proved by sequencing analysis. We conclude that DHPLC is a highly sensitive and specific method for p53 gene mutations.

• School Mathematics
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• v.18 no.4
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• pp.839-856
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• 2016

In 2009 revision and 2015 revision mathematics national curriculum, 'proof' was moved to high school from middle school in consideration of the cognitive development level of students, and 'proof by contradiction' was stated in the "success criteria of learning contents" of the first year high school subject while it had been not officially introduced in $7^{th}$ and 2007 revision national curriculum. Proof by contradiction is known that it induces a cognitive conflict due to the unique nature of rather assuming the opposite of the statement for proving it. In this article, based on the logical, mathematical and historical analysis of Proof by contradiction, we looked about the introductions and the applications of the current textbooks which had been revised recently, and searched for improvement measures from the viewpoint of discovery, explanation, and consilience. We suggested introducing Proof by contradiction after describing the discovery process earlier, separately but organically describing parts necessary to assume the opposite and parts not necessary, disclosing the relationships with proof by contrapositive, and using the viewpoint of consilience.

• Journal of The Korean Association For Science Education
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• v.30 no.5
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• pp.557-575
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• 2010

The purpose of the study was to suggest the characteristics and goals of the science teaching model for use as criteria in selecting the appropriate teaching model for science in secondary schools. These characteristics and the goals have been organized based on the analyses of the literature on the teaching and/or instructional model. The teaching models have been classified into four areas, and the characteristics and goals of each area have been summarized as follows: $\cdot$ Traditional models: teaching of scientific knowledge through lectures, acquisition of scientific knowledge through discovery, acquisition of inquiry process skills through inquiry-based teaching/learning $\cdot$ Transitional models: demonstration and discovery as teaching strategies, acquisition of inquiry process skills through inquiry approach, acquisition and change of scientific knowledge $\cdot$ Modernistic model - conceptual change models: differentiation of scientific knowledge, exchange of misconceptions for scientific concepts - learning cycle models: conceptual differentiation, exchange of misconceptions, acquisition of science process skills Also described in this paper are the model's characteristics and goals that can be used as the criteria for selecting the appropriate teaching model for the subject that will be taught.

• Investigative Magnetic Resonance Imaging
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• v.16 no.1
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• pp.1-5
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• 2012

Breast MRI is the most accurate adjunctive to the mammography for the screening of breast cancer. Despite lack of randomized controlled trials on the effectiveness of MRI screening, it is now recommended for the women at high risk for breast cancer by the American Cancer Society and the National Comprehensive Cancer Network based on several prospective observational studies. In Korea, a retrospective study reported that preoperative MRI screening of the contralateral breast in women with unilateral breast cancer was associated with reduced metachronous cancer incidence. To introduce breast MRI as a supplemental modality to screening mammography in Korea, standardization and education of interpretation, establishment of MR-guided biopsy and adequate indication, and evaluation of cost-effectiveness and should be preceded.