• Title/Summary/Keyword: Macroscopic viewpoint

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Middle School Students' Perceptions about Global Environmental Problems using Drawings (그리기를 활용한 중학생의 지구 환경 문제에 대한 인식 조사)

  • Cheong, Cheol
    • Hwankyungkyoyuk
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    • v.24 no.1
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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.

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A Study on the Overall Ship's Magnetism (총체적 선체자장에 관한 연구)

  • 정태권;이상집
    • Journal of the Korean Institute of Navigation
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    • v.15 no.2
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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.

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Some Problems on Acidic Plutonic Rocks in Korea (한국(韓國)의 성성심성암류연구(醒性深成岩類硏究)의 몇가지 과제(課題))

  • Lee, Dai Sung
    • Economic and Environmental Geology
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    • v.5 no.1
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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.

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An Analyical Study for Estimating Passenger Car Equivalents of Heavy Vehicles (대형차의 승용차 환산계수의 산정을 위한 해석적 연구)

  • 박창호;윤항묵;전경수
    • Journal of Korean Society of Transportation
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    • v.8 no.2
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    • pp.99-107
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    • 1990
  • This research addresses the effect of heavy vehicles (especially trucks) in terms of passenger car Equivalents from a capacity viewpoint. A formulation that estimate PCE in this paper is derived by introducing appropriate headway measurements into Huber's general equation for PCEs. In this equation, PCE value is expressed in terms of headways for four different kinds of pairs; pairs of leading and following vehicles ; P-P, P-T, P-T, T-T. The mean value of headway for each case is estimated through the regression analysis. Finally, the approach used in this research was compared with macroscopic approach which analyzed a speed-density relationship to evaluate PCE.

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Experiment and Prediction of Nonlinear Behavior at High Temperatures of Ferroelectric Ceramics Switched by Electric Field at Room Temperature

  • Ji, Dae Won;Kim, Sang-Joo
    • Journal of the Korean Ceramic Society
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    • v.54 no.3
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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 $110^{\circ}C$.

Chirality in Non-Hermitian Photonics

  • Yu, Sunkyu;Piao, Xianji;Park, Namkyoo
    • Current Optics and Photonics
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    • v.3 no.4
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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.

The Sementic Network Analysis of Elementary Students' Perceptions about Global Environment (초등학생들의 지구환경 인식에 대한 네트워크 분석)

  • Lee, Sanggyun;kim, Soonshik
    • Journal of the Korean Society of Earth Science Education
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    • v.11 no.3
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    • pp.212-223
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    • 2018
  • The purpose of this study is to investigate the perception of elementary students' 'global environment'. The research method used the Sementic Network Analysis method of the global environment elements which appeared in the students' explanation about the picture and the picture that emerged about the 'global environment'. The results of the study are as follows. First, as a result of analyzing the students' explanation of the pictures along with the pictures of the students, the elementary students were perceived negatively about the global environment such as 'environmental pollution', 'global warming' and 'trash problem'. Second, as a result of analyzing the image of the global environment expressed in the picture, there were many images expressed from a everyday viewpoint rather than a macroscopic viewpoint, and there was a tendency to express the earth personified. In addition, the picture expressing the clean earth environment expressed the most trees with natural environment elements and expressed the healthy earth with various natural elements such as sea, mountain, and land. Third, as a result of analyzing the difference of perception of global environment by grade, it was found that the difference of perception of global environment by grade was not much different.

The Rural-Life Settlement Process of the People with the Multi-Habitation Lifestyles (멀티해비 라이프스타일 실천자의 전원생활 정착과정에 관한 연구)

  • Choi, Jung-Min
    • Journal of the Korean housing association
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    • v.24 no.4
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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.

Analysis of Global Research Trend on Information Security (정보보안에 대한 연구 트렌드 분석)

  • Kim, Won-pil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.5
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    • pp.1110-1116
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    • 2015
  • This paper analyzes global research trend on information security. All technical fields based on information requires security so that discovering technologies (technical terms) which are developing newly or dramatically is able to guide the future direction of the field of information security. In this paper, the ultimate of this research is to figure out the technologies related to information security and to forecast the future through understanding their trends. The paper, as a beginning for the analysis on macroscopic viewpoint, contains measurement of yearly relatedness between technical terms from 2001 to 2014 by using temporal co-occurrence and interpretation of its meaning through comparing the relatedness with trends of top-related technical terms. And to conclude, we could find that Android platform, Big data, Internet of things, Mobile technologies, and Cloud computing are emerging technologies on information security.