• Journal of The Korean Association For Science Education
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• v.24 no.3
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• pp.417-428
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• 2004

Conservation reasoning makes operational thought possible as a functional tool and it is the essential concept not only in the area of science and mathematics but also in several aspects of daily life. The abilities to solve mathematical problems and that of scientific reasoning and abstract way of thinking depend on whether thereis conservation reasoning or not and they are critical concepts that enables us to confirm the steps of cognitive development. Therefor in the study, we emphasized the issue that is the ways to speed up the scientific era by analyzing the correlation between the formation of conservation reasoning and neuro-cognitive variables. About 50% of 1-3 grade students did not had conservation reasoning skills. The formation of conservations was not linear. Scientific reasoning ability, planing and inhibiting ability were significantly different in levels of conservation, And, conservation reasonings were significantly correlated with cognitive variables. Scientific reasoning and planning ability significantly explained about 20% of the conservation reasoning ability of 1-3 grades.

• Journal of the Korean earth science society
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• v.29 no.1
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• pp.60-77
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• 2008

We investigated the textbook model explaining a phase of the Moon and compared it with student models at the secondary levels in Korea. 20 high school students and 36 middle school students from suburb area participated in this study. Participants were interviewed to explain understandings about the cause of the Moon's phase with drawing their models. The results of this study showed that the textbooks now in use explain the phase of the Moon with one unique scientific model, while students displayed 6 different kinds of models including the scientific model. Furthermore the students tend to have comparatively scientific model modes as their grades increase and their scholastic ability levels become higher. Although the students have learned the Moon's phase in school, they still have alternative models because the textbook does not explain enough for the students to overcome their alternative conceptions. In the textbook, the model presented without explanation of the limitation of the model, so there can be a gap between the model in the textbooks and the models in the mind of students. With these findings, we propose complementary models for helping secondary school students to develop their understanding of moon phases.

• Journal of Radiation Protection and Research
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• v.38 no.2
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• pp.100-105
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• 2013

With the export of commercial nuclear power plants to UAE and that of a research reactor to Jordan, as well as the additional construction of domestic nuclear power plants, the demand of nuclear manpower is expected to increase sharply. Accordingly, nuclear manpower development is recently becoming an important issue. Major institutes involved in nuclear programs are well equipped with education and training procedures and resources. However, small and medium sized businesses have difficulties to educate their employees due to their limited resources and capacity for the education. Addressing the difficulties, this study is intended to develop and education course in accordance with the "Systematic Approach to Training (SAT)". For this, a survey is conducted on the need of education in small and medium sized businesses, based on which a pilot course on the basics of radiation is developed and operated. An assessment on the development and operation using a survey regarding participants response has shown high grades of performance, i.e. above 4.0 points (full mark: 5.0 points) on each level of expectancy, satisfaction and lecturers' capacity. The experience from this study will be used to develop other programs of nuclear power and ASME code, which are also identified from the need analysis.

• Particle and aerosol research
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• v.12 no.3
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• pp.95-102
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• 2016

Controlling exposures to occupational hazards is important for protecting workers. Certified facepiece respirators are recommended when engineering controls do not adequately prevent exposures to airborne nanomaterials. The objective of this study is to carry out the experimental performance test to investigate the fractional efficiencies of the filter media for two grades of facepiece respirators. Experimental performance evaluations were carried out for the test NaCl particles and silver nanoparticles. For media of respirator filter, the penetration of NaCl particles was less than 5% and the most penetrating particle size occurred at about 40 nm. For silver nanoparticles, the most penetrating particle size was about 20nm with higher efficiency than those of NaCl particles. Charge characteristics of airborne nanoparticles is important because the media of respirator filter is made by the electret filter media.

• Investigative Magnetic Resonance Imaging
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• v.12 no.2
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• pp.170-177
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• 2008

Purpose : To evaluate usefulness of MR imaging after serial brain US in the high-risk neonates before discharge of the neonatal intensive care unit. Materials and Methods : Retrospective comparison of 412 US and 121 MR scans in 121 neonates and young infants were performed. Grading of germinal matrix/intraventricular hemorrhage (GMH/IVH) was performed and presence of intracranial hemorrhage other than GMH/IVH and parencyma lesions was also analyzed. Results : Among the 242 lateral ventricles, Seven GMH and 46 IVH were additionally detected by MRI. On the other hand, 30 GMH were only detected by US. US demonstrated Grade 1/2/3/4 GMH/IVH in 24/8/13/0 ventricles each, while each grades were identified in 3, 49, 10, 2 ventricles on MR images. Other intracranial lesions additionally detected on MR images were cerebral hemorrhage (n=4), cerebellar hemorrhage (n=4), extraaxial hemorrhage (n=8), diffuse excessive signal change of the white matter (n=72), non-cavitary lesion (n=4), encephalomalacia (n=2), and ventriculomegaly (n=5). Conclusion : MR imaging could be an excellent complimentary study after serial brain US for additional detection of the intracranial pathology, particularly IVH and white matter lesions, though US would be better in follow-up of GMH in some neonates.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.12 no.2
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• pp.237-244
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• 2001

Objectives：Dysfunctional parent-child relationships have been associated with various mental and conduct disorders in adolescence and mental problems in adulthood as well. Most studies have done in clinical settings and little is known about the relationship between parenting and adolescent problem behaviors in community settings. This study is done to compare the perceived parenting and problem behaviors between problem behavior group and those of non-problem behavior group in male adolescents. Methods：The subjects of this study were 147 male high school students in Seoul, who do not have any known mental or conduct disorders and live with their real parents. Parental Bonding Instrument and Youth Self Report were administered to evaluate the perceived parenting and problem behaviors of adolescents. Results：There were significantly higher scores of mother overprotection in problem behavior group when comparing to non-problem behavior group. There was a significant association between mother overprotection and problem behavior when adjusting the number of family members, mother's job, parents' education level, grades, and religion. Conclusion：The parenting such as mother overprotection can be helpful to predict the problem behaviors in male adolescents, and appropriate parenting may prevent various problem behaviors in male adolescents.

• The Journal of Sustainable Design and Educational Environment Research
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• v.6 no.2
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• pp.66-90
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• 2007

The purpose of this study is to measure and analyze primary causes of indoor air pollution, including carbon dioxide, minute dust, and total volatile organic compounds, for each room before the beginning of a class through the time of discharge after the end of the class in general classrooms, computer rooms, and science rooms of three newly-established schools that opened in 2006, examine properties of indoor air environment in each room by educational activities at school, and determine effective management schemes; the results of this study can be summarized as follows: 1) As for implications for each item found in the mean for each place, since minute dust (PM10) was more likely to occur in time slots full of students' activities, such as a traveling class and a recess, than in the middle of a class and could be expected fully, it is necessary to make a scheme for cleaning in order to reduce minute dust within a room, for example, by usually using a vacuum cleaner indoors. 2) While carbon dioxide was expected to vary with the differences in the amount of breath between higher-graders and lower-graders in a general classroom but showed insignificant difference by grades, showing differences in pollution by four times at a maximum according to the opening of a window as expected, it is necessary to implement artificial or natural ventilation and take a positive measure, for example, by presenting a concrete ventilation scheme, in order to improve indoor air pollution at a room practice. 3) Total volatile organic compounds were found to exceed the standard by more than twice in general classrooms, science rooms, and computer rooms of the schools because of building materials, furnitures including desks and chairs, panels and boards for environment beautification, and items which could be detected even from students' clothes; while a field directly-reading tool was used, obtaining high reliability for the results, it is necessary to apply an analytical method based on process test separately for actual correct measurement if a significantly great amount of total volatile organic compounds appear as compared with other schools due to measuring expenses and consecutive measurements. 4) Since formaldehyde (HCHO) was generally found to exceed the standard in general classrooms, science rooms, and computer rooms, it is necessary to establish and operate a ventilator during a class in a computer room which requires airtightness and a science room in which an organic compound should be used for a class.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.373-378
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• 2014

To investigate the wear status of contact lenses by analyzing care of contact lenses container and actual condition of people wearing contact lenses and in Gyeonggido. The results were based on a questionnaire survey of 200 people who are the students of the middle school, the high school and the college among the clients of opticians to purchase contact lenses for six months from January 2013 to July 2013. According to the poll, the highest number of those polled, 139 (55.16%) people, said they were wearing cosmetic color contact lenses. Female respondents and male respondents were in the proportion of 177 (88.5%) to 23 (11.5%), respectively. 37 people (18.5%) who responded said "yes" to the question of them sharing contact lenses and glasses. 103 people (51.5%) answered "no" to the question of regularly replacing their lens containers. 148 people (74%) answered "yes" to the question of having glasses in order to investigate contact lens wearers user rate of glasses. The highest number of respondents, 127 people (63.5%), said "middle school" was the first time that they wore contacts. Meanwhile, 65 people (43.92%) said they initiated wearing glasses at 4th-6th grades. It is considered that it is necessary using proper contact lenses suitable for the clients' eye health in order of vision correction, rather than for cosmetic purposes. The role of the optician is considered to be very important for the proper management of the appropriate contact lens hygiene and regular optical check-ups of the contact lens wearers.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.225-233
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• 2007

The engineering properties of surface soils in natural terrain are changed due to wildfire. This change of engineering properties induced by wildfire is related to landslides occurrence. To investigate the change of soil properties caused by wildfire, the various soil tests are performed. The soil samples are obtained from the recently burned slopes of Yangyang area, Kangwon Province. The soil samples obtained from the burned slopes are classified into three types depending on the burning grade: the perfect burning grade, the intermediate burning grade, the non-burning grade. As the result of tests, the specific gravity and the dry unit weight of soils obtained from perfect and alternative burning grades are less than those of soils obtained from non-burning grade. It judges that an electronic force, ionic components and of soils are changed and organic matters in soils are burned by wildfire. The permeability of soil obtained from alternative burning grade is the lowest and that of soil obtained from perfect burning grade is the highest. The water-repellent layer is formed on soil surface by wildfire. The water-repellent layer is existed at the area of alternative turning grade, while the layer is not existed at the area of perfect burning grade. The water-repellent layer is collapsed in high temperature more than about $400^{\circ}C$.

• School Mathematics
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• v.13 no.4
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• pp.697-716
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• 2011

It is known that Korean students performs very well in mathematics but show poor attitude toward mathematics. However, attitude itself is an important goal of education and it also promotes students learning. Therefore, it is important and urgent for us to find a way to improve students' attitude toward mathematics. In this article, we tried to examine characteristics of Korean students' attitude toward mathematics and identify student and school level factors affecting it. For this purpose, we analysed National Assessment of Educational Achievement (NAEA) data in 2007 when NAEA was conducted especially focused on mathematics. Main findings of this research are as follows. First, we found that attitude toward mathematics got lower as students advanced to higher grades. And among 3 sub-domains of attitude toward mathematics, interest and self-confidence were lower than perception of value of mathematics. Secondly, attitude toward mathematics was mainly affected by student background variables such as gender, achievement, participation in private tutoring, father's education level. And while school factors contributed relatively little to students' attitude toward mathematics, teacher's perception on value of school education was positively related with students' attitude in high schools and emphasis on assessment was negatively related with students' attitude in elementary schools.