• Journal of The Korean Association For Science Education
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• v.37 no.5
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• pp.891-909
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• 2017

This study analyzed some of the discrepancies in quantitative and qualitative data focusing on cognitive and affective achievement in science education. Academic and affective achievement score of 308 high school students were collected as quantitative data, and 33 students were interviewed for qualitative data. We examined the causes and types of discrepancies in terms of testing tools. As a result from quantitative data, there were a large number of students with a big difference between subjects in cognitive achievement, and constructs in affective achievement. More than 20% of the students did not match tendency between achievements in two areas. Through interviews, some examples such as intentional control of science learning for future study and careers, different responses by differences in perception between school science and science, appeared. A comparison of quantitative data by testing tool between qualitative ones and interviews showed conflicting result, where most students evaluated themselves differently from their own quantitative data. That is due to the students' interaction with the testing tools. Two types of discrepancy related to testing tool are found. One is 'the concept difference between the item developer and students,' the other is 'the difference between students' exposed response and their real mindset.' These are related to the ambiguity of the terms used in the tool and response bias due to various causes. Based on this study, an effort is required to elaborate the testing item that matches students' actual perception and to apply students' science learning experience to testing items.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.90-96
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• 2002

The STS contents, emphasized in the 6th curriculum, in the chemistry textbooks(II) were analyzed. The STS contents in textbooks showed average value of 2.7%. The chapter of ‘chemical bond and compound' were included 3.8% of STS contents. And the chapter of ‘atomic structure and periodic table', ‘state of material and solution', ‘science of material', and ‘chemical reaction' contained 3.2%, 2.2%, 1.9%, and 1.9% of STS contents, respectively. When the STS contents were analyzed by STS topics of Piel, the results are as follows; 33.7% on effect of technological developments, 27.5% on environmental quality and utilization of natural source, 19.6% on human engineering, 13.8% on energy, and 5.4% on sociality of science. However, there were no topics on population, space research and national defense. When the STS contents were analyzed by student activities of SATIS, most of the activities were research and case study. There were few field activities of practical investigation, problem solving and decision making, research design and stimulation. There were no activities of role play.

• Child Health Nursing Research
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• v.20 no.4
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• pp.264-274
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• 2014

Purpose: The purpose of this study was to analyze papers on child rearing in Korea and to suggest future research and nursing practice directions for child rearing. Methods: An on-line search via 5 web sites yielded 201 research papers. The analysis of key concepts was based on the attributes of parenting and type of knowledge held by the parents. Results: The research papers found in the search were 27.3% experimental and 72.7% non-experimental. Among the participants, 77.0% of parents raising the child were mothers and the children were mostly young children under the age of one year. Types of knowledge related to child rearing varied widely, but explanatory knowledge (55.2%) was the most common, followed by prescriptive knowledge (30.0%) and descriptive knowledge (14.8%). For attributes of parenting, reaction to parenting (49.9%) followed by parenting behavior/practice (43.1%) was most common. Conclusion: Findings of this study indicate that further research is necessary regarding fathers and surrogate caregivers and on prescriptive knowledge for health promotion of children at different developmental stages. Also the results suggest a need for research toward developing child care policies.

• The Journal of Korean Academy of Sensory Integration
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• v.18 no.2
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• pp.15-28
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• 2020

Objective : The purpose of this study was to verify the construct validity of Short Sensory Profile-2 (SSP-2) for children with Autism Spectrum Disorder (ASD). Methods : Data were collected from SSP-2 for 120 parents of ASD children. Raw data were analyzed by applying the Rasch analysis to the goodness fit of person and item, item difficulty, rating scale, and separation reliability of SSP-2. Results : 7 persons in sensory processing area and 8 persons in behavioral response area were inappropriate criteria and excluded from the analysis. Item goodness-of-fit analysis determined that the If the Mnsq value is between 0.6 and 1.4 and the Z value is outside the ±2 range for nonconformity. this study All items in the instrument were found to have appropriate criteria. Item difficulty analysis in sensory processing area was high in item 13 (.48 logit) and low in item 10 (-.54 logit). In the behavioral response area, item 25 (1.58 logit) was high and item 30 (-.68 logit) was low. In the rating scale analysis, it was found that the 3-point scale is more appropriate than the 5-point scale. The separation reliability of sensory processing area was .90 and the behavioral response area was .95. Conclusion : This study verified the construct validity of SSP-2 and expected to be applied as a useful evaluation tool for children with ASD.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.509-520
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• 1996

Ultrafine calcim carbonate powders with the size of $0.05~0.1\;{\mu}m$ and the calcite phase were synthesized by the nozzle spouting method, which could be only obtained when high calcium ion concentration within slurry was maintained at the beginning of the reaction. But, in the regions of low ${Ca(OH)}_2$ concentration (0.5~1.0 wt%) or high ${Ca(OH)}_2$ concentration (<3.0 wt%), synthesized calcium carbonate powder was shown the large particle size with agglomeration. To obtain ultrafine calcium carbonate powder in this region, the methods of slurry circuation and $CO_{2}$ gas supply were changed during reaction. Resultly, it was possible to synthesize ultrafine particles (${\approx}0.05{\mu}\textrm{m}$)in the regions of low ${Ca(OH)}_2$ concentration (${\approx}0.5wt%$) and high ${Ca(OH)}_2$ concentration (${\approx}0.5wt%$), which can not be obtained the fine calcium carbonate powder still now.

• Applied Chemistry for Engineering
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• v.34 no.3
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• pp.279-284
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• 2023

Isothermal titration calorimetry (ITC) is a useful technique to obtain thermodynamic binding properties such as enthalpy, Gibbs free energy, entropy, and stoichiometry of the chelation reaction. A single independent binding site model was used to evaluate the thermodynamic binding properties in BaCl₂ and ethylenediaminetetraacetic acid (EDTA) in Trince and HEPES buffers. ITC enables us to elucidate the binding mechanism and find an optimal chelation condition for BaCl₂ and EDTA in the pH range of 7~11. Chelation of BaCl₂ and EDTA is a spontaneous endothermic reaction. As pH increased, entropic contributions dominated. The optimal pH range is narrow around pH 9.0, where 1:1 binding between BaCl₂ and EDTA occurs.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.1
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• pp.75-82
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• 2011

The numerical analysis of the reduction of reaction mechanism for the ignition of dimethyl ether (DME) was performed. On the basis of a detailed reaction mechanism involving 79 species and 351 reactions, the peak molar concentration and sensitivity analysis were conducted in a homogeneous reactor model. The reduced reaction mechanism involving 44 species and 166 reactions at the threshold value $7.5{\times}10^{-5}$ of the molar peak concentration was established by comparing the ignition delays the reduced mechanism with those the detailed mechanism. The predicted results of the reduced mechanism applied to the single-zone homogeneous charge compression ignition (HCCI) engine model were in agreement with those of the detailed mechanism. Therefore, this reduced mechanism can be used to accurately simulate the ignition and combustion process of compression ignition engine using DME fuel.

• Digital Contents
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• no.1 s.140
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• pp.57-61
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• 2005

최근에는 포털들이 대체로 모든 서비스를 집적해 서비스하고 있어 각 사이트만의 색깔을 쉽게 구분하기 어렵게 됐지만, 얼마 전만해도 포털들은 검색 포털, 메일 포털, 커뮤니티 포털등으로 세분화 돼 각각의 사업 영역을 확고히 해왔다. 이러한 기능 중심의 웹사이트는 사용자의 취향에 따라 즉각적인 반응을 일으켰다. 이러한 기능 중심의 웹사이트는 사용자의 취향에 따라 즉각적인 반응을 불러 일으켰다. 그동안 커뮤니티 서비스가 인기를 모으면 싸이월드, 다모임, 이이러브스쿨 등의 커뮤니티 포털이 사이트의 우위를 차지했고, 검색이 인기를 모으면 네이버나 야후가 떠오르는 등 사용자의 취향에 따라 상당한 기복을 보여왔다. 또한 인터넷이 특별한 목적을 갖고 접속하는 시절과는 달리, 최근에는 특별한 목적없이도 TV나 라디오를 켜듯 자연스럽게 인터넷에 접속하는 시대에 이르렀다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.05a
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• pp.173-176
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• 1998

FCC (Fluid Catalystic Cracking) 장치는 중질유의 원유와 잔사유로부터 가솔린과 heating oil. 디젤연료 제조 등에 사용되고 있다. 이 장치는 50년 동안 fine-powder 유동화에 중요하게 응용되고 있으며, 현재 세계적으로 약 350여 개의 장치가 조업되고 있다. FCC 장치에서 미세한 분해촉매는 촉매에 의한 중질유의 분해가 일어나는 상승관 (riser)과 촉매의 재생이 일어나는 재생반응기(regenerator) 사이에서 높은 속도로 순환되고 있다. (중략)

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.206.1-206
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• 1978

발효공업에 있어서 오염에 영향을 주는 미생물의 열살균 속도를 $120~130^{\circ}C$ 범위에서 조사하였다. 살균속도에 대한 온도의 영향은 Arrhenius식으로 다음과 같이 표시되었다. K=3.47$\times$$10^{28}$ EXP(-52.3 Kcal/RT)원형 반응기의 비이상혼합효과를 보기 위하여 난류영역에서 methylene blue 용액을 사용하여 계단압력을 주어 그 과도응답을 측정한 결과 체류시간 분포는 dispersion 모형에 잘 부합되었고 peclet number 100 을 얻었다. 당밀을 열분해시키면 hydroxymethl furfural이 생성되는 것을 확인하였고 온도와 pH에 따라 검토한 결과 고온의 산성용액에서 반응은 촉진되었다.