• 천문학회지
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• 제35권3호
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• pp.123-130
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• 2002

An elliptical accretion disk may be formed by tidally disrupted debris of a flying-by star in an active galactic nucleus (AGN) or by tidal perturbation due to a companion in a binary black hole system. We investigate the iron K$\alpha$ line profiles expecting from a geometrically thin, relativistic, elliptical disk in terms of model parameters, and find that a broad and skewed line profile can be reproduced well. Its shape is variable to the model parameters, such as, the emissivity power-law index, the ellipticity of the disk, and the major axis orientation of the elliptical accretion disk. We suggest that our results may be useful to search for such an elliptical disk and consequently the tidal disruption event.

• Journal of Yeungnam Medical Science
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• 제37권2호
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• pp.79-83
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• 2020

In the 21st-century postmodernism era, which represents diversity and relativity, one of the most essential elements in the field of education is to strengthen individual human values. Accordingly, we must focus on developing capacity in order to adapt to change. It is clear that the medical field maximizes the need for new judgments to solve life-related problems constantly, and this problem-solving capacity is an essential skill for a physician. Problem-solving capacity can be achieved simultaneously with creativity to apply them in an appropriate manner based on standardized expertise and well-trained skills. Creativity is also a key element that medical education is currently pursuing. Many studies on creativity have resulted in confusion and misunderstandings on the concept of creativity due to similar terms and varied definitions, such as creation, innovation, etc. In this study, we attempt to identify the importance of creativity in medical education by comparing and organizing concepts related to creative capacity.

• 천문학회보
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• 제44권1호
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• pp.56.1-56.1
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• 2019

The concordance LCDM model has been very successful at reproducing a wide range of observations. However, the nature of its main components, such as dark energy, dark matter, and inflation, are still unkown. Therefore, it is of prime importance to question the underlying hypotheses of the model and tests there prediction. While most constraints have been obtained assuming a LCDM universe, model-independent approaches, which do not make assumptions regarding the model, are a powerful approach. To falsify the LCDM model, I applied model-indepedent methods to the latests available data to test different aspects of the concordance model, such as the FLRW metric, the curvature, dark energy as the cosmological constant, and gravity as general relativity. The Universe is consistent with flat-LCDM with GR. However, at z>1, tensions start to appear, and more data are required.

• 영미문화
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• 제18권4호
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• pp.189-213
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• 2018

This paper aims to show how Thomas Hardy overturns conventional ideas in opposition and eventually disrupts the hierarchical order of ideas in the Victorian society of Tess of the D'Urbervilles. Divided into four sections, such as feeling/reason, purity/impurity, femininity/masculinity, and death/life, it examines how these binaries are deconstructed in the heroine's tragic life journey. The heroine Tess of the book, who boldly crosses the boundaries marked by traditional society, turns her image as a fallen woman into that of divinity, erasing the boundary between evil and good. In doing so, Hardy leads the reader to question the system of established values and reveals the illegitimacy of absolute values, thence stressing what all one can grasp in this world is nothing else than an absence of a central value. The relativity of truth and the power of overturning established value systems advertised in the book have significant implications for today's readers as well as for the Victorians.

• Journal of Astronomy and Space Sciences
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• 제38권1호
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• pp.39-44
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• 2021

In the general accretion disk model theory, the accretion disk surrounding an astronomical object comprises fluid rings obeying Keplerian motion. However, we should consider relativistic and rotational effects as we close in toward the center of accretion disk surrounding spinning compact massive objects such as a black hole or a neutron star. In this study, we explore the geometry of the inner portion of the accretion disk in the context of Mukhopadhyay's pseudo-Newtonian potential approximation for the full general relativity theory. We found that the shape of the accretion disk "puffs up" or becomes thicker and the luminosity of the disk could exceed the Eddington luminosity near the surface of the compact spinning black hole.

• 천문학회지
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• 제34권4호
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• pp.191-201
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• 2001

My contribution to these proceedings summarizes a general overview on High Resolution Shock Capturing methods (HRSC) in the field of relativistic hydrodynamics with special emphasis on Riemann solvers. HRSC techniques achieve highly accurate numerical approximations (formally second order or better) in smooth regions of the flow, and capture the motion of unresolved steep gradients without creating spurious oscillations. In the first part I will show how these techniques have been extended to relativistic hydrodynamics, making it possible to explore some challenging astrophysical scenarios. I will review recent literature concerning the main properties of different special relativistic Riemann solvers, and discuss several 1D and 2D test problems which are commonly used to evaluate the performance of numerical methods in relativistic hydrodynamics. In the second part I will illustrate the use of HRSC methods in several astrophysical applications where special and general relativistic hydrodynamical processes play a crucial role.

• East Asian mathematical journal
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• 제25권3호
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• pp.399-413
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• 2009

Whitehead's philosophy is evaluated as an applicable philosophy and an accurate, logical explanation system about the world through mathematics. Whitehead's ideological development can be divided into mathematical research, critical consciousness about sciences and philosophical exploration. Although it is presented as a whole unified conceptual framework to understand nature and human beings which is based on modern mathematics and physics in the 20th century, Whitehead's philosophy has not been sufficiently understood and evaluated about the full meaning and mathematics educational values. In this paper, we study relations of Whitehead's philosophy and the mathematical education. Moreover, we study implicity of mathematical education.

• 패션비즈니스
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• 제14권1호
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• pp.11-26
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• 2010

This study was carried out using personal measurement for female college students who have a great interest in fashion at 20-24 age, and examined somatotype character. As a means of a character type test, the grades were laid by using MBTI which proved to be objective, and relativity between character types was laid by conducting correlation analysis. The conclusions which can be drawn from this study are as followed. 1. In 4 preference index, which was classified by MBTI, Sensing(S) type was the highest of 17.27% at the average and 68.5% at the distribution rate each. The average of Extraversion(E) type was 14.56% and it's distribution rate was 64.5%. Index of types were : Intuition(N) 12.49%, Introversion(I) 11.75%, Perceiving(P) 12.50%. Average distribution rate of each types were : N 31.5%, I 35.5%, P 40.3%. And average of Sensing(S) type was the lowest, 11.09%. Like American Students, the subjects of this study showed higher in the E type than in the I type. The distribution rate of 16 character types of MBTI were : ESTJ 18.5%, ESFP 13.7%, ISTJ and ESFJ 9.7%. But INTP and INFP were low, 2.4% and 0.8%. 2. Average sizes of subjects for this study were : height 160.49cm, weight 51.83kg, bust 83.22cm, waist 65.49cm, hips 90.70cm. As compared with measurement of women at 20-24 age of Size Korea(2004), the subjects of this study showed less, about 0.2-5cm in height, 0.2-2cm in circumference except in waist, and 0.5-3.6cm in length. 3. After examining the relativity between personal measurement categories of the subjects and character type through the MBTI, Extraversion(E) type showed inverse correlation in stature, height, biacromial breadth, and subcutaneous fat thickness of posterior iliospinale. Contrary to the E type, the Introversion(I) type showed positive correlation. Sensing(S) type showed inverse correlation only in biacromial breadth, Intuition(N) type showed positive correlation in most categories including height, width and the subcutaneous fat thickness. Thinking(T) type showed positive correlation in bust point-bust point, chest depth and hip width. Feeling(F) type, on the other hand, showed inverse correlation. The Judging(J) type showed inverse correlation in stature, height, length and the parts of chest. In contrast, Perceiving(P) type showed positive correlation in other categories including biacromial breadth, same as the J type.

• 대한임상검사과학회지
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• 제48권1호
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• pp.22-29
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• 2016

혈중 gamma-glutamyltransferase (GGT)는 지금까지 간기능장애와 대표적인 알코올 섭취 관련 지표로서 폭넓게 사용되어 왔다. 현재 다양한 질환과의 관련성이 밝혀지면서 그 관심이 커지고 있다. 본 연구에서는 고도의 음주군에 해당하는 대상자를 제외하고 GGT 수치가 정상 범위에 속하는 대상자들에서 GGT 수치에 따른 관상동맥 질환 위험 요인과의 관련성을 살펴보고, 연령과 성별에 따른 특성을 비교 검토 하였다. 분석 자료는 2011 국민건강영양조사 데이터를 이용하였다(N=3,619). GGT(IU/L) 수준에 따라 사분위수(quartile) 네 군으로 나누었을 때 GGT기준은 남성의 경우 순서대로 10~20, 21~27, 28~38, 39~71 IU/L 이었고, 여성의 경우 각각 6~12, 13~16, 17~22, 23~42 IU/L 였다. 대부분의 변수에서 평균치는 GGT 4분위수로 갈수록 수치가 높게 나타났으나, 남성에서 연령과 저밀도콜레스테롤은 GGT 2분위수에서 수치가 가장 높았다. FRS와 10년 관상동맥 질환 위험도는 남성에서 GGT 2분위수에서 유의하게 높았고, 여성의 경우 GGT 4분위수에서 유의하게 높았다. 여성의 경우 GGT 수준이 높아질수록 연령이 증가하였으나, 남성의 경우 GGT 2분위수에서 가장 높았다. 연령 70대에서 남성의 경우 1,2분위수 분포가 가장 많고, 여성의 경우 3,4분위수 분포가 많아 그 차이가 뚜렷하게 나타났다. GGT 수치가 정상 범위에 속하더라도 GGT 수치가 증가함에 따라 여러 위험인자와 관련성이 있음을 증명하였다. 그러나 GGT 수치 증가와 함께 관상동맥질환 관련 수치와 10년 위험도 관련 예측치 증가에 대한 부분은 연령과 성별에 따라 서로 다른 양상을 보였다.

• 정보관리학회지
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• 제33권2호
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• pp.157-176
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• 2016

Cited-by Linking 서비스는 CrossRef에서 제공하는 주요 서비스 중 하나로 해당 논문이 DOI를 통하여 얼마나 인용되었는지 누적하여 집계된 데이터이다. 이에 본 연구에서는 KISTI의 학술정보통합관리시스템에서 월단위로 구축 관리하는 Cited-by Linking 데이터를 분석하여 자연과학과 공학 분야의 인용 패턴을 규명하고자 하였다. 이를 위해서 전체 기탁된 21만 건 중 자연과학과 공학 분야 총 170,999건(315종)을 분석 대상으로 하고, 2016년 3월까지 누적된 Cited-by Linking 데이터를 수집하였다. 연구의 분석 결과, 첫째, 글로벌하게 인용될 가능성에서 사용 언어는 영향을 미치고 있으며, 둘째, SCIE 및 SCOPUS 등재 여부 역시 인용가능성에 상당 부분 기여하고 있음을 확인하였다. 셋째, 자연과학 분야는 거의 동일한 주제 분야에서 인용을 받고 있으며, 상대적으로 공학 분야는 타주제 분야에서 더 인용 받고 있음을 파악하였다. 이러한 연구의 결과는 자연과학과 공학 분야의 세부주제 분야별 인용 행태를 규명하고, 향후, 인용 행태에 관한 연구에서 유용하게 활용될 것으로 기대한다.