• Journal of The Korean Association For Science Education
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• v.9 no.1
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• pp.101-111
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• 1989

본 연구의 목적은 광합성과 관련하여 한국 국민학교 5학년과 중학교 2학년 학생들이 갖고 있는 오개념을 조사하고, 학생들의 개념이해 정도, 논리적 사고능력, 그리고 학생배경변수들 사이의 상호관계를 조사하는 것이다. 세가지의 도구들이 이 연구를 위해 개발되었다. 광합성 개념검사 (Photosynthesis Concepts Test)는 광합성과 관련된 개념들의 이해를 평가하기 위해, 삐아제의 논리적 사고력 검사(Piagetian Cogical Reasoning Test)는 PCT에 포함된 3종류의 논리적 사고들, 변인 통제, 조합적 사고력, 상관관계 사고능력을 평가하기 위해, 그리고 실문서는 학생들의 배경변수들에 대한 정보를 얻기 위해 개발되었다. 이 도구들은 20명 의 국민학교 5학년, 239명의 중학교 2학년 학생들에게 시행되었다. 이 연구의 결과는 두집단의 학생들이 "먹이를 만든다"는 의미, 먹이의 정의, 식물에 의한 빛의 사용, 식물 뿌리와 잎의 기능들, 광합성 산물, 그리고 광합성을 위한 조건들과 관련하여 오개념을 갖고 있음을 보여 주었다. 국민학교 5학년과 중학교 2학년 사이의 개념 이해의 향상은 식물에 의한 빛 이용의 본질, 한 체계내에서 생물들간의 물질 교환, 포도당, 지방, 단백질 등에 대한 지식에서 보여졌고, 그래프를 해석하는 능력에서 또한 중학교 2학년 학생들이 앞섰다. 향상을 보인 항목들은 교과서에서 보다 많은 강조점을 두거나 상위의 논리적 사고능력을 요구하는 것들이었다. 희귀분석 결과, 전년도 과학성적과 논리적 사고력이 PCT 성취도에 가장 예견력이 높은 두 변수이며 5학년의 경우 성취도의 약 22%의 변량을, 중2의 경우 성취도의 약 40%의 변량을 설명하였다. 후속연구로서 내용의 추상성, 적절성, 그리고 요구되는 논리적 능력면에서 교수조건의 변형을 통한 오개념의 변화와 감소에 대한 실험적 연구가 제시되었다.

• Journal of the Korean Chemical Society
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• v.62 no.5
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• pp.398-411
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• 2018

The purpose of this study is to investigate the effects of research project activities using the science writing heuristic on science inquiry abilities and attitudes toward science in high school students. For this purpose, we conducted the research project activities using the science writing heuristic consisting of questioning, experimental design, observation, argument and evidence, reading, and reflection steps for 73 students of the second year of science core course in high school in Jeonnam. In order to analyze the effects of the program, we surveyed the scientific inquiry ability and attitude toward science, investigated the perception of the research project class applying science writing heuristic, and conducted interviews when there was difficulty in interpreting the results. And the results of this study are as follows. First, among the science inquiry abilities, the score of Reasoning, Hypothesis setting, Finding variables, Operational definition, Experimental design, Graphing and data interpretation, Generalization was significantly improved statistically (p<.05), but the score of Expectation was not statistically significant (p>.05). Second, among the attitudes toward science, the score of 'Leisure interest in science', 'Enjoyment of science lessons', 'Career interest in science' was significantly improved statistically (p<.05). And the score of 'Attitude to scientific inquiry' decreased but it's not significant statistically. The high school research project applying science writing heuristic had a positive effect on scientific inquiry ability and scientific attitude but it could be burden to students because it is led by students in a form different from general science class for a long time. And so continuous study on research project that minimize these disadvantages and maximize their merits is needed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.165-175
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• 2006

To analyze the deformation and failure of slopes, generally, two types of model, Polynomial model and Growth model, are applied. These two models are focused on the behavior of the slope by time. Therefore, this research is more focused on predicting of slope failure than analyzing the slope behavior by time. Generally, Growth model is used to analyze the soil slope, to the contrary, Polynomial model is used for rock slope. However, 3-degree polynomial($y=ax^3+bx^2+cx+d$) is suggested to combine two models in this research. The main trait of this model is having an asymptote. The fields to adopt this model are Gosujae Danyang(soil slope) and Youngduk slope(rock slope), which are the cut-slope near national road. Data from Gosujae are shown the failure traits of soil slope, to the contrary, those of Youngduk slope are shown the traits of rock slope. From the real-time monitoring data of the slope, 3-degree polynomial is proved as excellent system to analyze the failure and behavior of slope. In case of Polynomial model, even if the order of polynomials is increased, the $R^2$ value and shape of the curve-fitted graph is almost the same.

• Journal of Korean Elementary Science Education
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• v.31 no.4
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• pp.490-500
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• 2012

This study was to examine elementary male and female students' spatial abilities, science process skills, and graph construction and interpretation abilities in order to understand the effect that their spatial abilities and science process skills would have on their graph abilities. To conduct this study, total 12 classes of 435 pupils, 6 classes each from grades 5 and 6 in elementary schools were selected for subjects. The number of male student was 207 and that of female one was 228 of them. And previous test papers of spatial abilities, of science process abilities, and of graph abilities were retouched and updated for reuse in new tests. The results of this study are briefed as follows: Firstly, when spatial abilities for male and female group were compared, female group showed a little higher rate of correct answering than male, but not providing statistically significant gap. Secondly, the science process skill tests revealed basic process skills of both groups were more excellent than their integrated process skills, while female group was found to have more correct answers than male, all of which were proving statistical distinction. Thirdly, of graphing skills for two groups, the graph interpretation skills turned out to be better than the graph construction skills, with female group scoring higher than male and with meaningful difference. Fourthly, both between spatial abilities and graph abilities, and between science process skills and graph abilities, static correlations existed with statistical meaning. In other words, those with higher spatial abilities or science process skills were to do better in constructing and interpreting graphs.

• Journal of Science Education
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• v.37 no.3
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• pp.525-537
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• 2013

The purpose of this study was to investigate science integrated process skill of the students in science education center for the gifted. In order to do this, 'free-response test for the assessment of science process skills' developed by Yu-Hyang Kim(2013) was administered to 102 students(15 in elementary school science class, 58 in middle school science class I, and 29 in middle school science class II) who attend the program of science education center for the gifted in C university. The assessment tool measured 9 skills ; formulating inquiry questions, recognizing variables, formulating hypotheses, designing experiment, transforming data, interpreting data, drawing conclusions, formulating generalizations, and evaluating the designed experiments. As a result, the students in science education center for the gifted had relatively high scores in the area of 'formulating hypotheses' and 'recognizing variables', but they had relatively low scores in the area of 'transforming data', 'interpreting data', and 'evaluating the designed experiments'. The 2 items' percentage of correct answers were below 40% ; one is about a drawing a line graph in 'transforming data', and the other requires finding improvements of the experimental design in 'evaluation'. There was no significant difference between boys' scores and girls's one, and between the scores of students in the field of biology and those of students in the other fields(physics, chemistry, and earth science) in science integrated process skills. And there was significant difference according to the periods receiving the gifted education in 'formulating generalizations'. The teaching and learning has to focus on improving science integrated process skills in the program of science education center for the gifted and teaching and learning materials needs to be developed.

• Journal of Energy Engineering
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• v.21 no.4
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• pp.419-426
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• 2012

A transient, three-dimensional, two-phase flow analysis code, CUPID, has been developed in KAERI. In this work, we performed a preliminary analysis using the CUPID code to investigate the thermal-hydraulic behavior of the moderator in the Calandria vessel of a CANDU reactor. At first, we validated the CUPID code using the three experiments that were performed at Stern Laboratories Inc. To avoid the complexity to generate computational mesh around the Calandria tube bundles, a porous media approach was applied for the region. The pressure drop in the porous media zone was modeled by an empirical correlation. The results of the calculations showed that the CUPID code can predict the mixed flow pattern of forced and natural convection inside the Calandria vessel very well. Thereafter, the analysis was extended to a two-phase flow condition. Also, the local maximum temperature in the Calandria vessel was plotted as a function of the injection flow rate, which may be utilized to predict the local subcooling margin.

• Journal of The Korean Association For Science Education
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• v.28 no.1
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• pp.32-46
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• 2008

The purpose of this study was to analyse the qualitative and quantitative characteristics of paper-pencil tests for exploring its appropriateness as a selection tool of the gifted in science. For this purpose, we developed two (internal and external) item analysis frameworks, and applied these frameworks to analyse qualitative characteristics. Also, we analysed the relationship between two characteristics. The results of analysing qualitative characteristics revealed that the portion of items with acceleration context exceeding middle school curriculum level was relatively large, which caused low content validity. Furthermore, there was considerable deviation in content and context by subject matter and year, which caused test unstability. Items measuring knowledge domain was the most prevalent, and too much weight on data interpretation & analysis domain in inquiry process skills. In case of creativity test, the portion of items measuring convergent thinking was much larger than that of divergent or associative thinking. Most of these items were represented by using pictures and tables rather than using graphs. Item types of multiple-choice and short answers were superior to essay types. Discrimination index, on the whole, was appropriate (above 0.3), but item difficulty showed a vast deviation ($0.01{\sim}0.90$). Correlation coefficients among subject matters and test tools were very low, and test reliabilities were also low. Low item difficulty & high discrimination index item types were distinguishable. Items with acceleration context were more discriminating than enrichment context. Implications of developing quality paper-pencil test items in the selection of gifted students are discussed.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.647-655
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• 2004

PISA (Program for International Student Assessment) 2003, the second cycle of PISA, collected data with respect to students' cross-disciplinary problem solving capabilities. Problem solving is defined as the ability to use cognitive processes to solve real cross-disciplinary problems. For the purpose of PISA 2003 assessment, three problem types were chosen: Decision Making, System Analysis and Design, and Trouble Shooting. For this paper a preliminary analysis on Korean students' responses to the PISA 2003 problem-solving items was conducted. The quantitative analysis mainly focused on the difficulties of the PISA 2003 items, while the quantitative analysis dealt with students' responses to open-ended items, which helped understand Korean students' cognitive style and reasoning processes. According to the item analysis result, Korean students had difficulty in representing their answers with pictures or graphs, and interpreting long and complex text. They also showed low achievement with relatively unfamiliar topics or tasks. The paper concluded with several suggestions on improve the quality of science education.

• School Mathematics
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• v.5 no.4
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• pp.477-506
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• 2003

In this paper, we analyze nine-grade students' conceptions of parameters, their relation to unknowns and variables and the process of understanding of letters in problem solving of equations and functions. The roles of letters become different according to the letters-used contexts and the meaning of letters Is changed in the process of being used. But, students do not understand the meaning of letters correctly, especially that of parameter. As a result, students operate letters in algebraic expressions according to the syntax without understanding the distinction between the roles. Therefore, the parameter of learning should focus on the dynamic change of roles and the flexible thinking of using letters. We develop a self-regulation model based on the monitoring working question in teaching-learning situations. We expect that this model helps students understand concepts of letters that enable to construct meaning in a concrete context.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.640-655
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• 2013

The purpose of this study is to analyze the cognitive demands level of the description about 'changes of state' and 'kinetic theory' on the 'science 1' textbooks by the 2007 revised curriculum. The three types of curriculum analysis taxonomy have been used to analyze the cognitive demands level of those contents on the 6 kinds of 'science 1' textbooks. The most higher level of cognitive demands about the concepts have been discussed here due to the focus of the concepts. The first, the cognitive demand level about 'three states of substances' depending on the motion of their particles in 6 textbooks is a early formal operational stage because of using by the application of kinetic theory. The second, the cognitive demand level about 'diffusion' and 'evaporation' is a early formal operational stage, because the particles move around faster so they can change their position. The third, the cognitive level of the pressure and volume in a gas is a early formal operational stage because of explaining only phenomena in simple correspondence with formal model of kinetic theory. And simple functional relationships beyond linear on the graph of the volume and pressure of gas, the volume and temperature of gas is also a early formal operational stage. The fourth, the cognitive level of the energy of heat by a change of the state is also a early formal operational stage because kinetic theory picture accepted as providing explanation by the change of the state. And functional relationships beyond linear on the graph of the explanation of boiling point of water in water is also a early formal operational stage.