• Journal of the Korean Institute of Gas
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• v.20 no.2
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• pp.66-71
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• 2016

Nowadays, a number of sensors which are placed in industrial complex are monitoring areas involving chemical leak and other faults. However, even in the presence of the sensors, chemical leaks, sometimes involving huge amount of chemicals, continuously led to big losses in the industrial complex. In most industries, sensor installation has been performed using past experience or using senor manufacturers' guideline; which leads to poor performance of the installed sensor grid. Therefore, we investigate an optimal placement methodology of point sensors for rapid detention and response when chemical leaks happen. This research suggests a generalized formulation suitable for the optimized decision making of minimizing number of sensors to be placed and increasing the fraction of covered scenarios under assumption of negligible effect of other structures. The proposed method has been verified for suitable performance for simple leak scenario simulations, by achieving the safety objectives and guaranteeing safe process operations.

• Journal of The Korean Association For Science Education
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• v.24 no.6
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• pp.1063-1069
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• 2004

This study investigated the effects of grouping method in solving chemistry problems using Think-Aloud Paired Problem Solving (TAPPS). Three classes (125 students) of a co-ed high school in Seoul were randomly assigned to the control, the homogeneous TAPPS, and the heterogeneous TAPPS groups. Prior to the instructions, a test of awareness of metacognition was administered. In the treatment groups, students were grouped into either homogeneous or heterogeneous group on the basis of their pre-achievement levels, and worked in pairs on chemistry problems about chemical equation and stoichiometry. Students' analytical skill, problem solving ability, and awareness of metacognition were examined after the instructions. One-way ANCOVA results indicated that the scores of the homogeneous TAPPS group in the analytical skill test were significantly higher than those of the heterogeneous TAPPS group. However, there were no significant differences among the three groups in the problem solving ability and the awareness of metacognition.

• Journal of The Korean Association For Science Education
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• v.25 no.3
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• pp.327-335
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• 2005

This study investigates student achievement and science-related attitudes on STS hypothetical deductive instruction strategy in the water section of high school chemistry. Two 11th grade co-ed high school classes participated in the study; one control group and one treatment group. After being taught for 10 class periods during the second semester. ANCOVA analysis revealled no significant difference (p>.05) between two groups' achievement tests. However, analysis by ANCOVA did show that the scores for science-related attitudes in the treatment group were significantly higher than those of the control group (p<.05). In particular, the scores of science learning contents and science value about science-related attitude were significantly higher in the treatment group.

• Journal of The Korean Association For Science Education
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• v.19 no.3
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• pp.377-388
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• 1999

In this study, a learning-teaching model enhancing the students to ask questions was developed and the influence of its application to the lesson of 'Chemical Change and Elements' of the 8th grade was investigated. This learning-teaching model was constructed initially by completing the work-sheet to activate student's question-asking, then by writing down their questions or uncertainties in the class, and finally with the feedback of student's question to the individual and to the class. Treatment and control groups (2 classes each) were selected from a girls' middle school in Seoul. and taught for 12 class hours during 4 weeks for this study. Before instruction, the test of attitudes toward science lessons and the test of adoption of scientific attitudes were administered, and the science scores of the previous course were obtained for the covariate. After instruction, the conception test. the achievement test, the test of attitudes toward science lessons, and the test of adoption of scientific attitudes were administered. The TOSRA (Test of Science-Related Attitudes) was used both for the test of attitudes toward science lessons and for the test of adoption of scientific attitudes. The study revealed that the treatment group showed significant differences from the control group in the scores of the conception test (p<.01) and of the achievement test (p<.05). But in attitudes toward science lessons and adoption of scientific attitudes. there were not significant differences between the two groups, even though the scores of the treatment group were a little higher than those of the control group. Educational implications of the effect of science teaching on the questioning activity of students are also discussed.

• Journal of Gifted/Talented Education
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• v.14 no.2
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• pp.1-18
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• 2004

This study attempted to survey the present status of the eight students who, 17 years from now, had participated in a special program for 170 days preparing for early entrance to the KAIST. With six students who responded to the questionnaire previously sent, the study focused on each participant's achievement at present, his evaluation on Accelerated Education, his personal opinions on early entrance to university and Gifted Science Education. From the survey, we could find out that three participants had received a doctorate and they are currently working as researchers at research center or professors at university. The other three participants are working as researchers at research center after receiving the M. S. Academic achievements vary according to each participant, but three of them, who ranked high in research achievement, had their articles published in international journals of the SCI level even when they were between 25 and 28 of age. Two of them in particular showed outstanding engineering and developing the commercial modem for IMT 2000 for the first time in Korea. One participant entered Harvard University to major in physics and afterwards studied the law in UCLA. He is now a professor in the law department. Concerning the evaluations on Accelerated Education and early entrance system, four participants answered positively while two participants expressed negative attitudes. When asked their opinions on the Gifted Education in Korea, such problems were pointed out as too much pressure of entering the first-class universities, the tendency to avoid choosing science-related major at universities, the lack of education system that encourages creative thinking, etc. It is necessary that the accelerated education play an important role to maximize their hidden potentials. It remains to be seen in what places these six participants will find themselves and of what ideas they will come up within the next 17 years. It will be worthwhile to wait until then for another survey.

• Journal of the Korean Chemical Society
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• v.56 no.2
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• pp.290-296
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• 2012

This study analyzed the research papers published in three (2 domestic and 1 foreign) journals, in order to understand the recent trend of chemistry education research. We selected Journal of the Korean Chemical Society (JKCS) and Journal of the Korean Association for Science Education (JKASE) as the domestic journals, and Journal of Chemical Education (JCE) as a foreign journal. The papers published from 2000 to 2009 were analyzed. As the result, the chemistry education research theme focused on 'teaching method and education technology', 'learner's characteristics', and 'chemical concept and experiment' in the order of frequency. The research on 'curriculum and textbooks' was performed often in JKCS reflecting Korean social environment. The most researched chemistry education goal was the 'conceptual understanding/change' followed by 'achievement/grade' in JCE and 'experiment/inquiry skill' in JKCS, and 'attitude/interest/motivation' in JKASE. The research subjects were focused to 'middle or high school students' in JKCS, in contrast to the 'university students' in JCE. More concern to the higher education is required in the domestic research. The most frequently used research method was 'survey/ examination' followed by 'experimental research' in JCE and JKASE and 'data/material analysis' in JKCS. We discussed the implication on future chemistry education research.

• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.362-373
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• 2016

In this study, ionic compound in the science textbooks developed under the 2009 revised national curriculum were analyzed in terms of the scientific concept and model description and the student understanding through the questionnaires. Analysis of textbooks was performed for science2 of middle school and chemistry I & II of high school. Questionnaire was carried out with 194 students including middle school 2nd grade and high school 1st-3rd grade. The results are as follows: First, as a result of analysis of textbooks, scientific concepts and models used to explain the ionic compound showed differences depending on the types of textbooks. In addition, scientific models were provided with or without explanation for the scientific concepts. Second, analysis of the questionnaire showed that students didn’t properly understood scientific concepts and models in the ion formation, stoichiometric ratio between ions.

• Journal of the Korean Chemical Society
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• v.41 no.5
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• pp.239-245
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• 1997

The sorption kinetic was studied to evaluate feasibility of removing PCBs from mineral oil with activated carbon. Adsorption efficiency for Aroclor 1242 which is composed of lower chlorinated PCB formulations was $\geq$ 95%, whereas the adsorption efficiency for Aroclor 1260 having higher chlorinated constituents was considerably lower with the efficiency falling to 75%. The observed difference in the adsorption efficiency is attributed to the geometry of PCBs with non-planar and coplanar structure. The concentration of coplanar PCBs is appreciably higher in Aroclor 1242. Since toxicity is primarily associated with coplanar congeners, the preferential adsorption of coplanar congeners by activated carbon accounts for the fact that toxicity reduction can be achieved through this process. The efficiency of process was assessed in terms of Toxicity Equivalence Factor (TEF).

• Journal of The Korean Association For Science Education
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• v.20 no.2
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• pp.344-352
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• 2000

In this study, high school students' environmental conceptions and attitudes, and their relationships with affective variables (self-esteem, enjoyment of science lesson, and leisure interest in science) were investigated. Students' environmental conceptions were found to be low, and male students' environmental conceptions were higher than female students. However, the environmental attitudes of female students were more positive than those of male students. There were no differences between male and female students in the ecocentric attitudes, but male students had more egocentric attitudes than female students. Students of higher prior science achievement level possessed higher level of environmental conceptions than their counterparts. Among the affective variables studied, leisure interest in science was significantly correlated with environmental attitudes.

• Journal of the Korean Chemical Society
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• v.55 no.1
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• pp.7-13
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• 2011

As an aid towards improving the treatment of exchange and correlation effects in electronic structure calculations, it is desirable to have a clear picture of concepts of exchange-correlation functionals in computational calculations. For achieving this aim, it is necessary to perform different theoretical methods for many groups of materials. We have performed hybrid density functional theory (DFT) methods to investigate the density charges of atoms in rings and cages of carbon nanotube. DFT methods are engaged and compared their results. We have also been inclined to see the impression of exchange and correlation on nuclearnuclear energy and electron-nuclear energy and kinetic energy. With due attention to existence methods, B3P86, B3PW91, B1B96, BLYP and B3LYP have used in this work.