• Journal of the Korean institute of surface engineering
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• v.34 no.5
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• pp.367-377
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• 2001

Plasma is generated by electrical discharge. Most plasma generation has been carried out at low-pressure gas typically less than one millionth of atmospheric pressure. Plasmas are in general generated from impact ionization of neutral gas molecules by accelerated electrons. The energy gain of electrons accelerated in an electrical field is proportional to the mean free path. Electrons gain more energy at low-pressure gas and generate plasma easily by ionization of neutrals, because the mean free path is longer. For this reason conventional plasma generation is carried out at low pressures. However, many practical applications require plasmas at high-pressure. In order to avoid the requirement for vacuum pumps, researchers in Korea start to develop plasmas in high-pressure chambers where the pressure is 1 atmosphere or greater. Material processing, environmental protection/restoration and improved energy production efficiency using plasmas are only possible for inexpensive bulk plasmas. We thus generate plasmas by new methods and plan to set foundations for new plasma technologies for $21^{st}$ / century industries. This technological research will play a central role in material processing, environmental and energy production industries.

• Biomaterials and Biomechanics in Bioengineering
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• v.3 no.1
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• pp.47-57
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• 2016

Results from multiple high profile experiments on the parameters influencing the impacts that cause skull fractures to the frontal, temporal, and parietal bones were gathered and analyzed. The location of the impact as a binary function of frontal or lateral strike, the velocity, the striking area of the impactor, and the force needed to cause skull fracture in each experiment were subjected to statistical analysis using the JMP statistical software pack. A novel neural network model predicting skull fracture threshold was developed with a high statistical correlation ($R^2=0.978$) and presented in this text. Despite variation within individual studies, the equation herein proposes a 3 kN greater resistance to fracture for the frontal bone when compared to the temporoparietal bones. Additionally, impacts with low velocities (<4.1 m/s) were more prone to cause fracture in the lateral regions of the skull when compared to similar velocity frontal impacts. Conversely, higher velocity impacts (>4.1 m/s) showed a greater frontal sensitivity.

• Atmosphere
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• v.16 no.4
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• pp.303-318
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• 2006

A parameterization of gravity wave drag induced by cumulus convection (GWDC) proposed by Chun and Baik is implemented in the KMA operational global NWP model (GDAPS), and effects of the GWDC on the forecast for July 2005 by GDAPS are investigated. The forecast result is compared with NCEP final analyses data (FNL) and model's own analysis data. Cloud-top gravity wave stresses are concentrated in the tropical region, and the resultant forcing by the GWDC is strong in the tropical upper troposphere and lower stratosphere. Nevertheless, the effect of the GWDC is strong in the mid- to high latitudes of Southern Hemisphere and high latitudes of Northern Hemisphere. By examining the effect of the GWDC on the amplitude of the geopotential height perturbation with zonal wavenumbers 1-3, it is found that impact of the GWDC is extended to the high latitudes through the change of planetary wave activity, which is maximum in the winter hemisphere. The GWDC reduces the amplitude of zonal wavenumber 1 but increases wavenumber 2 in the winter hemisphere. This change alleviates model biases in the zonal wind not only in the lower stratosphere where the GWDC is imposed, but also in the whole troposphere, especially in the mid- to high latitudes of Southern Hemisphere. By examining root mean square error, it is found that the GWDC parameterization improves GDAPS forecast skill in the Southern Hemisphere before 7 days and partially in the Northern Hemisphere after about 5 days.

• Journal of the Korean Society of Earth Science Education
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• v.17 no.1
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• pp.70-85
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• 2024

The purpose of this study was to find out what impact climate action has on study participants and why climate action education is difficult in high schools. For this purpose, a basic qualitative research method was selected, and the study participants were five middle school students at the time of the activity. The results of this study are as follows. Due to the climate action in middle school, the participants' career path changed specifically and their climate literacy was cultivated. And climate action education in high schools was not enough. Environmental subjects that provide climate action education were difficult to open because they were not chosen by many students, and it was unrealistic to provide climate action education during creative experiential activities due to the burden of college entrance exams. The discussion points of this study are as follows. Climate action needs to be encouraged among middle school students because it helps shape career paths and cultivate climate literacy. Additionally, because sustainability is important in climate action, there is a need to establish specialized courses in climate action education in the curriculum of elementary, middle, and high schools so that climate literacy can be maintained consistently.

• Journal of the Korean earth science society
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• v.43 no.2
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• pp.253-264
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• 2022

The effect of decreased human activity on the urban heat island intensity (UHII) was analyzed using the observed temperature data of six sites (including one reference area) in Daejeon Metropolitan City from February to May of 2019 to 2021. Depending on the observation site, UHII decreased by approximately 20% in 2020 and 2021 compared to 2019 before COVID-19. The decrease in human activity increased UHII at night and decreased it during the daytime. Consequently, UHII diurnal amplitude increased by approximately 20% in 2020 and 2021 compared to 2019, irrespective of location. The decrease in UHII did not appear to be significantly correlated with natural factors such as wind speed and social distancing steps. In contrast, UHII was correlated with social distancing and significantly reduced air pollutants after COVID-19, with the most significant correlation observed for NO₂.

• Korea Journal of Hospital Management
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• v.28 no.2
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• pp.1-8
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• 2023

Purpose: This study was conducted to identify the impact of human rights sensitivity and patient rights awareness of first-year students in clinical practice on clinical practice adaptation and to prepare practical and systematic personality development program education alternatives to foster high-quality medical personnel. Method: As for the research method, an online survey of 155 medical and nursing students from two universities in G-do (76 medical students and 79 nursing students) was conducted, and the collected data were T-test, ANOVA, Scheffe test, Pearson's correlation coefficient and step-by-step multiple regression analysis using SPSS WIN/25.0. Findings: The results of the study are as follows. First, as a result of analyzing the differences in each variable according to general characteristics, human rights sensitivity had a significant impact on gender, patient rights recognition on personality type, and clinical practice adaptation had a significant impact on major selection motivation. Second, the factors affecting the adaptation of first-year college students to clinical practice had a significant impact on extroverted personality and patient rights perception among personality types (regression model results F=6.38 (p<).001), 24.2% explanatory power). Conclusion: This study suggests that education and policy efforts are needed to foster accurate awareness of human rights issues by developing flexible and flexible extracurricular activity programs in the operation of the curriculum to strengthen medical and nursing students' ability to adapt to clinical practice and improve awareness of human rights issues.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.424-431
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• 2017

Objective: Study on the application of high pressure processing (HPP) for dark-firm-dry (DFD) beef was conducted to observe whether HPP has any impact on physical properties and to evaluate oxidative deterioration during refrigerated storage under vacuum. Methods: The longissimus lumborum muscles obtained from Friesian Holstein steers ($33{\pm}0.5$ months old) with 24-h postmortem pH higher than 6.0 were vacuum-packed and subjected to pressurization at 200, 400, and 600 MPa for 180 s at $15^{\circ}C{\pm}2^{\circ}C$; the samples were then stored for 9 days at $4^{\circ}C{\pm}1^{\circ}C$ and compared with control (0.1 MPa). Results: HPP increased meat pH by 0.1 to 0.2 units and the tenderness of cooked DFD beef significantly with no significant effects on meat texture profile. The stability of meat pH was well maintained during refrigerated storage under vacuum. No clear effects were found on the activity of catalase and superoxide dismutase, however, glutathione peroxidase activity was significantly reduced by high pressure. HPP and storage time resulted in aroma changes and the increasing amount of malondialdehyde and metmyoglobin relative composition. Conclusion: Although the increasing amount of malondialdehyde content, metmyoglobin formation and aroma changes in HPP-treated samples could not be avoided, HPP at 200 MPa increased $L^*$ and $a^*$ values with less discoloration and oxidative deterioration during storage.

• 한국노년학
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• v.40 no.1
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• pp.131-146
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• 2020

The objective of this study is to examine the relationship between attitude in digital usage and life satisfaction level of the middle-aged people and older adults, and to analyze Sequential Mediation Effects of online networking activity and information producing and sharing in the online context. To achieve the main objectives, we conducted Hayeys'(2013) Process for SPSS Macro. The followings are the results of the study: First, there is a strong relationship between the attitude towards digital usage and the life satisfaction. Second, the results showed that impact of attitude in digital usage on life satisfaction among the older people is 0.291 unit higher, when they are engaged both in online networking activity and digital information production/sharing activities compared to involved in online networking activity alone. The results of the study is meaningful in that they can be used as a baseline data for reconsideration of digital usage and life satisfaction of the older adults, by providing comprehensive examination of relationship among attitude in digital usage, life satisfaction, online network activities, and digital information production·sharing activities of the older adults.

• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1530-1538
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• 2009

KISTI-ACOMS ver. 2.0 has been distributed to more than 340 academic societies and used by more than 130 academic societies for 4 years since 2005 and still is desired for use by lots of other academic societies. But contrary to the desire and requests for system upgrades of academic societies, ACOMS has not been improved for last 3 years and some academic societies began to use domestic or foreign similar pay online peer review systems. In this paper, a new integrated portal service system is suggested in order to attempt national production cost-saving and quality improvement of academic information by creating and collecting high quality scientific and technologic academic information inexpensively. We come up with methodology of integration and utilization of a personal academic activity portal system interoperable with other services of KISTI, an open citation reference database automatically constructed by authors' activity and a journal evaluation system based on impact factor.

• Journal of the Korean earth science society
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• v.28 no.1
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• pp.1-13
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• 2007

The purpose of this study was to understand characteristics of students' reflective inquiry disposition in the contexts of classroom and to find educational implications for the promotion of the reflective inquiry activity in the inquiry-based class. In this study, we determined a characteristic of the reflection inquiry by examining students' responses showed in response to the different class types in high school earth science inquiry class. The result of the study indicated that the difference between the newly developed class type to promote the reflective inquiry and the existing inquiry class type was found significant. The newly developed reflective inquiry class had a multitude of reflective inquiry statements related to various elements of data context in terms of the quantity and diversity of the reflective inquiry. In conclusion, we found that the newly developed class type had a positive impact on the students' reflective inquiry activity. We believe that the development of the inquiry activity to promote students' reflective inquiry is critical.