• Korean Journal of Cognitive Science
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• v.27 no.2
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• pp.325-353
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• 2016

The visual span refers to the number of letters that can be accurately recognized without moving one's eyes. The size of the visual span is affected by sensory factors such as perimetric complexity, crowding, and mislocation of letters. Korean Hangul utilizes rather unique alphabetic-syllabary writing system, quite different from English and Chinese writing systems. Due to this combinatorial nature of the script, the visual span for Hangul characters can also be affected by the letter type (e.g., CV vs CVCC). The present study examined the effect of syllable complexity on the visual span for Hangul by comparing letter recognition accuracy across four letter type conditions (C only, CV, CVC, and CVCC). We also aimed to determine the meaningful letter type(s) that is associated with differences in reading abilities in Korean. Using a trigram presentation method, we found that overall recognition accuracy declined as syllable complexity increased. However, the visual span for CVC type was greater than that for CV type, suggesting that the effect is not necessarily linear, and that there might be other factors affecting the visual span for these types of letters. C and CV type showed fairly strong positive correlations with reading comprehension, suggesting that these might be the meaningful units for measuring visual span in relating to reading abilities.

• Journal of The Korean Association For Science Education
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• v.36 no.6
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• pp.895-910
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• 2016

The purpose of this study is to explore secondary students' progression in group norms and argumentation competency through collaborative reflection about small group argumentation. The progression is identified as the development of group norms and an epistemic understanding of argumentation with the enhancement of group argumentation competency during collaborative reflection and argumentation lessons. Participants were four first grade middle school students who have different academic achievements and learning approaches. They participated in ten argumentation lessons related to photosynthesis and in seven collaborative reflections. As a result, the students' group norms related to participation were developed, and the students' epistemic understanding of argumentation was enhanced. Furthermore, the students' group argumentation competencies, identified as argumentation product and argumentation process, were advanced. As the collaborative reflection and argumentation lessons progressed, statements related to rebuttal increased and different students suggested a range of evidence with which to justify their claims or to rebut others' arguments. These findings will give a better idea of how to present an apt application of argumentation to science teachers and science education researchers.

• Korean Journal of Ichthyology
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• v.22 no.1
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• pp.9-16
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• 2010

Osmoregulatory capabilities of a euryhaline medaka, Oryzias dancena (Beloniformes; Teleostei), was examined with a particular emphasis on adult and larval viability during direct salinity changes. O. dancena adults were highly capable for hyper-osmoregulation as well as hypo-osmoregulation, as evidenced by no adverse effect on their viability during the direct transfer either from complete freshwater ($0^{\circ}/_{\circ\circ}$) to $40^{\circ}/_{\circ\circ}$ salinity, or from $70^{\circ}/_{\circ\circ}$ to $0^{\circ}/_{\circ\circ}$. Furthermore, the phased increase of external salinity with acclimation periods allowed them to survive at a salinity as high as $75^{\circ}/_{\circ\circ}$. However, tolerant capability to acute salinity increase in early larval stage was much less than in adult stage, based on the finding that the tolerance range of salinity increase was only $15^{\circ}/_{\circ\circ}$ from freshwater, indicating that the hyper-osmoregulation system might not be fully developed in the early larval stage. On the contrary, the hypoosmoregulation system could be more solidified in O. dancena larvae, as evidenced by their good survival even after direct transfer from $45^{\circ}/_{\circ\circ}$ to $0^{\circ}/_{\circ\circ}$. Knowledge achieved in this study could form the basis for a wide scope of researches including ecotoxicogenomics and geneexpression assay using this model species.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.244-250
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• 2004

Biological activities and application of Sanguisorbae officinalis L. were investigated. In the enzymological physiological activities, the electron donating ability (EDA) was 54.9% in 10 ppm and it was over 90% over 50 ppm and SOD-like activity was high as 65.4% in 1000 ppm, it was gradual increased. As inhibitory effect of xanthine oxidase, it was 17.9% in 200 ppm and little low as 36.9% in 500 ppm and inhibitory effect of tyrosinase. As the result of measuring the lipid oxidation, all the concentrations of medical ion treatments had the ability to keep it from acidification and metal ion blocking effects about the lipid oxidation promoting factors ($Fe^{2+}$ and $Cu^{2+}$), $Fe^{2+}$ was better than $Cu^{2+}$ and all concentrations of medical ion treatments was 40% in 50 ppm. When it was applied into normal skin-softener it showed safe effect so that we can expect that as the natural material of cosmetics.

• Applied Microscopy
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• v.31 no.1
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• pp.1-8
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• 2001

The morphological features of neuronal dendritic spines are changed their shapes, sizes and density in response to physiological or pathological conditions . Therefore, exact analysis of spines warrants understanding of neuronal function. The size of the spine is at the borderline of resolution with light microscopy. High voltage electron microscopy Provide excellent resolution of the spines with proper stain techniques thanks to its higher resolution and penetration power. We evaluated more effective staining method for observing dendritic spines after labeling Purkinje cells with anti-calbindin 28 kD immunohistochemistry or Golgi staining methods. 4 fm thickness sections were observed with high voltage electron microscopy and some morphometric analyses were performed. Both Golgi staining and immunohistochemistry revealed the detail structures of the Purkinje cell such as soma, dendrites, and dendritic spines. High voltage electron micrographs with Golgi staining provide more precise morphology and are easy to measure. Average density of spine is $24.5{\pm}3.6/10{\mu}m$ and its length is $1.12{\pm}0.22{\mu}m$. For quantitative analysis of the spines, high voltage electron, micrographs with Golgi staining are more effective. This preliminary result is expected to be useful for further study of spine plasticity in various conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.408-417
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• 2015

The aim of the study was to verify the effects of simulation-based stroke care education on the nursing performance ability and satisfaction among nursing students. The study used a nonequivalent control group pretest-posttest design. A total of 64 nursing students in a nursing college participated in this study. The participants were assigned conveniently according to the academic year to either the experimental group in 2013 (n = 32) or control group in 2014 (n = 32). The experimental group received a simulation-based stroke care education, and the control group received a clinical placement with self-directed practicum. The data was analyzed using the Mann-Whitney U test. The results showed that the scores of the overall nursing performance ability (z = -3.373, p < .001) and satisfaction (z = -3.245, p = .001) in the experimental group were significantly higher than those in the control group. Overall, simulation-based stroke care education is an effective teaching strategy of improving the nursing performance ability and satisfaction among nursing students.

• Journal of The Korean Association For Science Education
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• v.24 no.6
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• pp.1245-1255
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• 2004

The purpose of this study is to develop a valid and reliable evaluating instrument for elementary school fifth and sixth graders. The instrument is developed through R&D procedure, which includes two checks of science specialist and two field trials of the instrument. Evaluating items are content-free for each science inquiry skill. Each science inquiry element is based on SAPA and the 7th curriculum. This study has selected 10 science inquiry skills(observing, classifying, measuring, predicting, inferring, recognizing of a problem, controlling variables, interpreting data, drawing a conclusion, designing an experiment), formulated a clear definition of the elements of science inquiry skills, and established the objectives of evaluation. The content areas are divided into three categories, material and energy, life and environment, and the earth and circulation. Each category contains 10 items. So the instrument consists of 30 items. The content validity of items, objectivity of the scoring keys, and clarity of the items has been checked twice by specialists in science education. At the same time, two field trials were performed to produce the reliability of the instruments, discrimination index, and item difficulty index. The instrument has the content validity is 91.6%, reliability 0.79, objectivity 93.3%, discrimination index 0.30, and item difficulty index 66.1%.

• Journal of the Korean Applied Science and Technology
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• v.39 no.3
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• pp.386-396
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• 2022

This study was carried out as a descriptive correlation study to identify the knowledge and performance of CPR of nursing students who have experience in CPR education and to explore the relationship between them. Participants in this study were 204 nursing college students who were enrolled in the 4th year of nursing at two universities located in G Metropolitan City from October 18 to October 30, 2018. For the collected data, IBM SPSS Win 21.0 version Program was used. The correlation between the subject's CPR knowledge and performance was evaluated using the Pearson Correlation Coefficient. There was a positive correlation between CPR knowledge and CPR performance (r=.22, p=.01), and it was found that the higher the CPR knowledge, the higher the CPR performance. Since this study is convenient extraction of nursing students from two universities in G Metropolitan City, there may be limitations in generalizing the results of this study. It is a self-reported indirect measurement rather than a direct measurement that measures by observing, reflecting the subject's subjectivity, and there is a concern that the effect of education may not be measured objectively. Therefore, further research using a direct measurement tool of CPR performance is needed.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.4
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• pp.412-421
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• 2010

As a most conservative, minimally invasive trial against early caries lesions, resin infiltration concept has been introduced and studied mainly about effective materials and pre-treatment methods of surface layers to arrest the lesion effectively, which is still going on. This study was performed with an aim of evaluating the efficacy of arresting the caries process in the natural incipient lesions in spite of removing the surface layers and we obtained the results as follows: 1. It was revealed that infiltration groups(1, 3, 5) showed lower radio-density decline between pre- and posttreatment than control groups(2, 4, 6)(p<0.05). 2. Group 5, in which the surface layer was removed with hydrochloric acid, showed the most significant anticariogenic effect(p<0.05). 3. Under SEM evaluation after infiltration, group 1 and 3 showed more irregular destruction and intensive loss of surface layers than group 5. In conclusion, it was thought resin infiltration can be an effective tool against the early caries lesions although surface layers are removed.

• Journal of Music and Human Behavior
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• v.6 no.1
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• pp.55-80
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• 2009

The objective of this study was to improve the self-expression of children through Orff activities. In this study, three (3) children from D day care center in Seoul who demonstrated withdrawn behaviors were chosen as research subjects, based on a self-expression test score of 50 points. The activities were conducted for 6 weeks, totaling fourteen (14) sessions, with each session being scheduled for forty (40) minutes. Across 14 sessions, the researcher conducted, analyzed and compared the self-expression scale of subjects, measured during the third and the last session. The researcher then qualitatively analyzed verbal and non-verbal self-expression behaviors of subjects by video recording the session. The analysis results shown by the study are as follows. First, the results of a quantitative analysis of the self-expression scale showed significant changes in self expression. Furthermore, the results of a qualitative analysis of verbal self-expression showed positive changes in self-perception and an increase in feelings of independence and activity than that of initial sessions.