• 대한화학회지
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• 제52권5호
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• pp.569-579
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• 2008

• 한국환경교육학회지:환경교육
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• 제24권1호
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• pp.76-87
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• 2011

The purpose of this study was to investigate middle school students' perceptions about global environmental problems using drawings. The study was involved the collection of drawing data from 112 ninth grade students from a middle school in Daegu Metropolitan City. The environment task was administrated to students drew a drawing of an global environmental problems and explained their drawing in their own words. Also, students was asked to write what he or she can do to solve global environmental problems. The results are as follows: First, air pollution is the most important global environmental problem, followed by water pollution, global warming, sea level rise, deforestation, waste, loss of biodiversity, and so on. Second, the students' drawings were characterized into two aspects: One is a macroscopic viewpoint and the other is everyday viewpoint. Third, the students' practical action plan to do solve global environmental problems were walk, public traffic, do not throw trash, plant trees, etc. Educators should take into account the perceptions of global environmental problems and teaching-learning strategies to enhance students' understanding of global environment.

• 한국항해학회지
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• 제15권2호
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• pp.1-11
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• 1991

The ship's magnetic compass even if corrected is feasible to indicate the erroneous information due to the change of this ship's magnetism. But if the north-seeking sensor of the transmitting magnetic compass system is located where the effect of the ship's magnetism is the least , that problem is expected to be removed. In this paper, as a basic research to enhance the accuracy and the stability of the ship's magnetic compass by placing the north-seeking sensor at the adequate location, the theoretical model for the overall ship's magnetism were studied from the macroscopic viewpoint, The parameters of the theoretical model were determined by the least square method on the assumption that the overall magnetism of a ship can be regarded as that of the prolate spheroidal magnetic body. The agreement between the modelled and the observed values was found to be good.

• 자원환경지질
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• 제5권1호
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• pp.21-38
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• 1972

In this paper, the author discussed about following subjects for the studies of acidic plutonic rocks in Korea. (1) The criteria of distinction between ortho-origin and para.origin of acidic plutonic rocks using the statistic chemical treatment of lognormal type distribution of H.L. Arhens (1954, 1957, 1963), the normative Q-Ab-Or triangle of O.F. Tuttle and N.L. Bowen(1958), plagioclase twin type of M. Gorai(1952) and optical measurement of ordering degree of plagioclase of K. Uruno(1963), (2) Macroscopic structural classification of migmatites of K.R. Mehnert(l968), (3) Volcano-plutonism comparing the geological features in the younger orogenic belts in Japan and Cordillera in America and (4) The original sources of granitic magma in the viewpoint of isotope geology.

• 대한교통학회지
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• 제8권2호
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• pp.99-107
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• 1990

본 연구에서는 대형차의 승용차환산계수(PCE)를 결정하기 위해 혼합교통류의 흐름-저항의 관계를 나타내는 일반식을 확장하여 차두시간의 하여 항으로써 환산치를 산정하는 공식을 개발하였다. 여기서 차량배열 형태에 따른 각 경우 외 차두시간의 값은 수집된 교통자료의 희귀분석을 통해 추정토록 하였으며, 제시된 PCE치의 적절성을 검증하기 위해 거시적 접근방법에 의한 산정된 산치와 비교 분석토록 하였다.

• 한국세라믹학회지
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• 제54권3호
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• pp.235-242
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• 2017

Changes in polarization and thermal expansion coefficients during temperature increase of a poled lead zirconate titanate (PZT) cube specimen switched by an electric field at room temperature are measured. The measured data are analyzed to construct governing differential equations for polarization and strain changes. By solving the differential equations, an experimental formula for the high temperature behavior of ferroelectric materials is obtained. It is found that the predictions by the formula are in good agreement with measures. From the viewpoint of macroscopic remnant state variables, it appears that the processes of electric field-induced switching at different temperatures are identical and independent of temperature between $20^{\circ}C$ and $110^{\circ}C$.

• Current Optics and Photonics
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• 제3권4호
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• pp.275-284
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• 2019

Chirality is ubiquitous in physics and biology from microscopic to macroscopic phenomena, such as fermionic interactions and DNA duplication. In photonics, chirality has traditionally represented differentiated optical responses for right and left circular polarizations. This definition of optical chirality in the polarization domain includes handedness-dependent phase velocities or optical absorption inside chiral media, which enable polarimetry for measuring the material concentration and circular dichroism spectroscopy for sensing biological or chemical enantiomers. Recently, the emerging field of non-Hermitian photonics, which explores exotic phenomena in gain or loss media, has provided a new viewpoint on chirality in photonics that is not restricted to the traditional polarization domain but is extended to other physical quantities such as the orbital angular momentum, propagation direction, and system parameter space. Here, we introduce recent milestones in chiral light-matter interactions in non-Hermitian photonics and show an enhanced degree of design freedom in photonic devices for spin and orbital angular momenta, directionality, and asymmetric modal conversion.

• 대한지구과학교육학회지
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• 제11권3호
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• pp.212-223
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• 2018

본 연구의 목적은 초등학생들의 '지구환경'에 대한 인식을 조사하는데 있다. 연구방법은 '지구환경'에 대해 떠오르는 생각을 그림과 함께 그림에 대한 학생들의 설명에 나타난 지구환경 요소들을 언어네트워크 분석법을 사용하였다. 연구의 결과는 다음과 같다. 첫째, 학생들의 그림과 함께 그림에 대한 학생들의 설명을 분석한 결과 초등학생들은 '환경오염', '지구온난화', '쓰레기' 등과 같이 지구환경에 대해 부정적으로 인식을 하고 있었다. 둘째, 그림에 표현된 지구환경에 대한 이미지를 분석한 결과 우주적 관점보다는 일상적 관점에서 표현된 그림이 많았으며, 지구를 의인화하여 표현하는 경향이 있었다. 또한, 깨끗한 지구환경을 표현한 그림은 자연환경요소로 나무를 가장 많이 표현하였고, 바다, 산, 땅 꽁 등 다양한 자연요소로 건강한 지구를 표현하였다. 셋째, 지구환경에 대한 학년별 인식의 차이를 분석한 결과 학년에 따른 지구환경에 대한 인식의 차이는 크게 다르지 않다는 것을 알 수 있었다.

• 한국주거학회논문집
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• 제24권4호
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• pp.39-52
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• 2013

This study examined the key factors that significantly improved the demand of multi-habitation. It determined the factors at the macroscopic level (or push factors) and the microscopic level (or pull factors). Focusing on a microscopic viewpoint, this study looked at the process of settlement through investigating 78 MH residents in the Seoul metropolitan area. The survey included the questions, such as who they are, how they prepared for moving, and how much they enjoyed their rural lives. In addition, any differences in this process were analyzed depending on respondents' characteristics. Major findings are as follows: First, general macro-level circumstances seemed supportive for the MH lifestyles. Second, six keywords were determined to represent the recent MH trends. They are "semi-sedentism, clustering, young people, female, money, and policy". Third, the distances between the original towns for native residents and new second-home towns for MH residents affected the interactions among them. However, these two groups had better relationships when the second-home towns were apart from the original towns. I then considered the need of a buffer zone between the two residential areas for MH residents. The conceptual difference between MH residents (i.e., semi-sedentism) and original rural residents (i.e., sedentism) might require certain types of buffer zones to continue good relationships among them.

• 한국정보통신학회논문지
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• 제19권5호
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• pp.1110-1116
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• 2015

본 논문에서는 정보보안에 대한 글로벌 연구 트렌드에 대한 분석을 다룬다. 정보를 이용하는 모든 분야에서 보안을 필요로 하기 때문에, 새롭게 생성되거나 급격하게 발전하는 분야를 발굴하는 것이 정보보안의 방향을 설정하는 것이 될 수 있다. 이에 본 연구의 목적은 정보보안과 관련한 기술들을 파악하고, 이들을 트렌드 관점에서 해석함으로써 향후를 전망해보고자 한다. 현재의 수준은 거시적 관점에서의 분석을 위한 초기 연구로써, 기술들 사이의 연도별 공기정보를 이용하여 2001년부터 2014년까지의 연관성을 측정하고, 상위 연관 기술 자체의 트렌드와 상호 비교하여 그 의미를 분석하였다. 결론적으로는 안드로이드 플랫폼, 빅데이터, 사물인터넷, 모바일 분야, 클라우드 컴퓨팅이 정보보안에 유망한 기술 분야라 할 수 있다.