• Journal of The Korean Astronomical Society
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• v.37 no.1
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• pp.41-53
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• 2004

It has been a big mystery what drives filament eruptions and flares. We have studied in detail an X1.8 flare and its associated filament eruption that occurred in NOAA Active Region 9236 on November 24,2000. For this work we have analyzed high temporal (about 1 minute) and spatial (about 1 arcsec) resolution images taken by Michelson Doppler Imager (MDI) onboard the Solar and Heliospheric Observatory, Hoc centerline and blue wing ($-0.6{\AA}$) images from Big Bear Solar Observatory, and 1600 ${\AA}$ UV images by the Transition Region and Corona Explorer (TRACE). We have found that there were several transient brightenings seen in H$\alpha$ and, more noticeably in TRACE 1600 ${\AA}$ images around the preflare phase. A closer look at the UV brightenings in 1600 ${\AA}$ images reveals that they took place near one end of the erupting filament, and are a kind of jets supplying mass into the transient loops seen in 1600 ${\AA}$. These brightenings were also associated with canceling magnetic features (CMFs) as seen in the MDI magnetograms. The flux variations of these CMFs suggest that the flux cancellation may have been driven by the emergence of the new flux. For this event, we have estimated the ejection speeds of the filament ranging from 10 to 160 km $s^{-1}$ for the first twenty minutes. It is noted that the initiation of the filament eruption (as defined by the rise speed less than 20 km $s^{-1}$) coincided with the preflare activity characterized by UV brightenings and CMFs. The speed of the associated LASCO CME can be well extrapolated from the observed filament speed and its direction is consistent with those of the disturbed UV loops associated with the preflare activity. Supposing the H$\alpha$/UV transient brightenings and the canceling magnetic features are due to magnetic reconnect ion in the low atmosphere, our results may be strong observational evidence supporting that the initiation of the filament eruption and the preflare phase of the associated flare may be physically related to low-atmosphere magnetic reconnection.

• Korean Journal of Social Welfare
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• v.67 no.4
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• pp.279-299
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• 2015

This study examines the impact of Long-Term Care Insurance(LTCI) on family caregivers(especially focused on female household members) labor supply in South Korea. When public care and informal care are substitutes, LTCI will change allocation of time of family caregivers to spend more time to paid work. The impact of LTCI on labor supply depends on each country's institutional level of public care services. If public care can not substitute for informal care, labor supply of family caregivers will not rise significantly. The conclusions of vigorous empirical study from western countries' are incompatible and problem of endogeneity in terms of methodology has been raised consistently. The dataset of this study are used the third and ninth waves of Korea Welfare Panel. As a result, the introduction of LTCI had no effect on labor supply of household members. Robust findings suggest the positive effects of caregiving on labor market outcomes in simple comparison t-test, but not in fixed-effect regression. Compared with western countries, South Korea's public care services can be interpreted as a supplement to only part that remained at the level does not substitute informal care. These findings may suggest that if LTCI become much more prevalent in the future, senior citizens and family members will be able to choose the LTCI arrangement that best suits their needs.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1742-1752
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• 2013

A basal diet (0.8 g/kg dNa) was formulated in which each of the two sources ($NaHCO_3$ and $Na_2SO_4$) were supplemented in such a way to attain four levels (1.7, 2.6, 3.5, and 4.4 g/kg) of total dNa, respectively, under $4{\times}2$ factorial arrangement. Eight dietary treatments were replicated four times, with 40 birds in each replicate (n = 1,280). The diets supplemented with $Na_2SO_4$ to attain higher levels of dNa showed highest BW gain and feed intake (FI) during d 1 to 10 (interaction effects) while 2.6 g/kg dNa exhibited improved BW gain and gain:feed (FG) during d 11 to 20. Linear rise in daily water intake (DWI) was associated with diets containing increasing dNa during d 1 to 42 ($p{\leq}0.036$). During the first 10 d, DWI:FI was found highest in $NaHCO_3$ diets while $Na_2SO_4$ diets showed highest DWI:FI during last 10 d of the experiment ($p{\leq}0.036$). Increasing dNa and changing $Na_2SO_4$ with $NaHCO_3$ salt increased pH and resulted in poor growth performance. Dressing weight ($p{\leq}0.001$) and abdominal fat ($p{\leq}0.001$; quadratic effect) were reduced, whereas breast ($p{\leq}0.001$) and thigh (p<0.001) weights were aggravated with increasing dNa (linear effects). Present findings suggested higher levels of dNa from $Na_2SO_4$ as the supplemental salt in broiler diets would produce better growth performance, especially in first ten days of life, and improve carcass and body organ characteristics.

• Women's Health Nursing
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• v.1 no.1
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• pp.5-27
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• 1995

One of the important tasks for new parents, especially mothers, is to establish warm, mutually affirming interpersonal relationships with the new baby in the family, with the purpose of promoting the health development of the child and the well-being of the whole family. Nurses assess the quality of the behavioral characteristics of the maternal-infant interaction. The purpose of this longitudinal descriptive correlational study is to investigate the changes of the mother - infant interactions from postpartum 1 day to postpartum 8weeks of the transition to parenthood. The aim was to contribute to the development of theoretical under standing on which to base care toward promoting the quality of maternal - infant interaction. Data were collect ed directly by the investigator and at rained from Jul, 1, 1990 to Jun 8, 1991, Subjects were a random sample of 44 mothers, 44 who had a normal delivery (but with out other perinatal complications) at four general hospitals in Seoul. Instruments used were the Stainton Parent-infant Interaction Scale (1981). The first observations were made in the delivery room, followed by day 1, day 2, day 3 and 2 weeks, 4 weeks, 6 weeks and 8 weeks after, birth, for a total of 8 contacts. Observations in the hospital were made during the hour prior to scheduled feedings. The infant was placed beside the mother. Later contacts were made at home. Data analysis was don by computer using as SPSS program and included, Paired t-test, t-test and Pearson Correlation coefficient ; the results were as follows. 1. The daily maternal-infant interaction score for the initial contact ofter birth to 8 weeks postpartum had the lowest average score 5.21 and the highest 8.02(in a range of 0-10). This subject group of mothers needed Extra nursing supporting to promote their maternal-infant interaction. 2. The daily scores for the maternal-infant interaction tended to rise, showing a gradual improvement over the period of eight weeks. However, there were significantly different increases in maternal-infant interaction only from the first to second day (p=0.000) and from the fourth to sixth weeks ofter birth.(p=0.000) 3. When the seven items of maternal-infant interaction were evaluated items of maternal-infant inter action were evaluated separately, "Care taking for the baby" had the highest average score, 1.60(in a range of 0-2) and "Speaks to baby" the lowest, 0.8. All items, suggested the subjects' need of nursing intervention to promote maternal-infant interaction 4. There were positive correlations between certain general characteristics, namely, both a higher economic status (p=0.027) and breast feeding (p=0.021) and maternal-infant interaction.

• Journal of Nutrition and Health
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• v.50 no.4
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• pp.376-382
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• 2017

Purpose: The consistent rise in the number of foreign students in Korea demands an accurate and detailed investigation into their dietary practices and nutritional status. For these international students, assimilation into new cultures can be stressful. The influence this process may have on dietary behaviors as well as overall health cannot be overlooked. Methods: The researchers in this study sought to investigate the nutritional status and dietary practices of Ghanaian students studying in Korea. A total of 81 Ghanaian male students with an average age of $29.4{\pm}4.0years$ were sampled between May and June 2016. Investigations were carried out on the general characteristics of the participants, their daily food and nutrient intakes using a 24-h dietary recall method, meal skipping practices, and the nutritional quality of their diets based on their meal skipping habits. Results: The study revealed that the daily nutrient intake of subjects did not fully meet the daily recommended nutrient intake (RNI) established by Ghanaian Ministry of Health and the World Health Organization (WHO) and Food and Agriculture Organization (FAO), particularly for energy, calcium, iron, zinc, and vitamin B2 requirements. The Nutrient Adequacy Ratio (NAR) for calcium was very low, posing a deficiency risk to the participants. Meal skipping practices among participants changed significantly after arriving in Korea. The study also compared the diet quality indicators (Nutrient Adequacy Ratio and Mean Adequacy Ratio) of those who skipped meals ${\geq}7times/week$ with those who skipped meals < 7 times/week. Participants who skipped meals ${\geq}7times/week$ were shown to have lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Conclusion: Ultimately, the study found that meal skipping among Ghanaian students was common, and their daily nutrient intakes did not meet the set dietary standards. Those who skipped meals ${\geq}7times/week$ had lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Based on our study findings, we recommend that nutrition education should be organized for the Ghanaian student community in Korea using our results as a template to draw up a nutrition program that is culturally appropriate.

• Tunnel and Underground Space
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• v.25 no.2
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• pp.186-198
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• 2015

This paper aims for the ultimate goal to optimize the work place environment through assuring the optimal required ventilation rate based on the analysis of the airflow. The working environment is deteriorated due to a rise in temperature of a coal mine caused by increase of its depth and carriage tunnels. To improve the environment, the ventilation evaluation on J coal mine is carried out and the effect of a length of the tunnel on the temperature to enhance the ventilation efficiency in the subsurface is numerically analyzed. The analysis shows that J coal mine needs $17,831m^3/min$ for in-flow ventilation rate but the total input air flowrate is $16,474m^3/min$, $1,357m^3/min$ of in-flow ventilation rate shortage. The temperatures were predicted on the two developed models of J mine, and VnetPC that is a numerical program for the flowrate prediction. The result of the simulation notices the temperature in the case of developing all 4 areas of -425ML as a first model is predicted 29.30 at the main gangway 9X of C section and in the case of developing 3 areas of -425ML excepting A area as a second model, it is predicted 27.45 Celsius degrees.

• Journal of Korean Society on Water Environment
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• v.30 no.2
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• pp.175-183
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• 2014

The influence of temperature on the treatment efficiency of chlorinated organic substances contained in groundwater by permeable reactive barrier which is composed of $Fe^{\circ}$ has been investigated by constructing the Pourbaix diagrams for Fe-$H_2O$ system at different temperatures based on thermodynamic estimation. In aerobic condition, the equilibrium potentials for $Fe^{\circ}/Fe^{2+}$ and $Fe^{2+}/Fe^{3+}$ were observed to increase, therefore, the dechlorination reaction for organic pollutants by $Fe^{\circ}$ was considered to decline with temperature due to the diminished oxidation of reactive barrier. The result for the variations of the ionization fraction of $Fe^{2+}$ and $Fe^{3+}$ ion in the pH range of 0 ~ 2.5 obtained by employing Visual MINTEQ program showed that the ionization fraction of $Fe^{2+}$ increased with pH, however, that of $Fe^{3+}$ decreased symmetrically and the extent of the variation of ionization fraction for both ions was raised as temperature rises. The equilibrium pH for $Fe^{3+}/Fe(OH)_3$ was examined to decrease with temperature so that the treatment efficiency of chlorinated organic substance was expected to decrease with temperature due to the enhanced formation of passivating film in aerobic condition. The change of the reactivity of a specific chemical species with temperature was defined quantitatively based on the area of its stable region in Pourbaix diagram and depending on this the reactivity of $Fe^{3+}$ was shown to decrease with temperature, however, that of $Fe(OH)_3$ was decreased monotonously as temperature is raised for $Fe^{3+}/Fe(OH)_3$ equilibrium system. In anaerobic condition, the equilibrium potential for $Fe^{\circ}/Fe^{2+}$ was observed to rise and the equilibrium pH for $Fe^{2+}/Fe(OH)_2$ were examined to decrease as temperature increases, therefore, similar to that for aerobic condition the efficiency of the dechlorination reaction for organic substances was considered to be diminished when temperature rises because of the reduced oxidation of $Fe^{\circ}$ and increased formation of $Fe(OH)_2$ passivating film.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.562-572
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• 2020

This study analyzed subjectivity of underachievers on Peer Assisted Learning(PAS) in culinary skills related subject for providing better educational environment through consideration of educational efficiency of particular teaching method. Q Methodology was employed for analysing of responses of a small group of the students. The research found that three types of distinctive structures of responses of the students' subjectivity. The first one was Increase learning effectiveness type(Type1, N=8), the second one was Development of lesson materials for passive students(Type2, N=8), and the last one was Practical self-directed learning needs development(Type3, N=6). From the result, PAS was an effective teaching method for underachievers for encouraging participation of study program, helping to rise self-confidence in subject's tasks, and awareness of self directed learning and additional study on subjects matters. The study, however, found that students could consider themselves as an interruption to other students' study progress, and could feel other students' awareness as a burden. At last, forming a class by deeper consideration on the learning levels of each students and providing additional educational contents for encouraging self directed learning are necessary for the better efficiency for the future.

• Journal of The Korean Association of Information Education
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• v.22 no.5
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• pp.509-517
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• 2018

As the necessity of maker education is being emphasized and the app generation is now entering school, expectations concerning the impact of app development education are rising in the field of education. The introduction and rise in popularity of a new type of education, such as app development education, requires a change in attitude among teachers. Therefore, this study focused on the concerns of in-service teachers regarding app development education by applying the Concerns-Based Adoption Model (CBAM) of Hall and Hord (2015). For this purpose, the data was collected from 23 in-service teachers who attended a short teacher training session that introduced app development training. The data was converted to the relative intensity based on the stage of concerns questionnaire (SoCQ) scoring device and was expressed as the SoCQ profile. The results of the survey concerning app development education showed that the stage 0 concern (unconcerned) was reported most frequently by teachers and the stage 4 concern (consequence) was reported least frequently. This kind of result, which is typical at the beginning of the introduction of a new education program, indicates that teachers recognize app development education but do not have sufficient information regarding it. Qualitative results also showed that teachers understand the educational possibilities of app development education, but they were worried about the difficulties expected to be applied in the field. Based on these results, we suggest that more detailed information on app development education be provided through teacher training.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.5
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• pp.11-21
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• 2007

Currently in the country, the necessity of seismic analyses is increasing due to the increase of demand and interest in seismic design. Especially, shear wall apartments are constructed mostly for a residental building so seismic analyses for the apartment are actively executed. For the seismic analysis of the shear wall apartment, it may be not efficient in time and effort to model the entire structure by a finite element mesh. Therefore, an equivalent model is needed to simulate the dynamic behavior of the structure by decreasing the number of degrees of freedom. In this study, a method to form an equivalent model that is simple and easy to use was proposed utilizing effective mass coefficient that is highly correlated to mode shape of the structure. This equivalent model was obtained by replacing a shear wall structure with an equivalent frame structure having beams and columns. This model can be used very effectively when excessive seismic analyses are necessary in a short period because it can be operated in any commercial program and reduce the analysis time. Also, it can model floor slabs so it can represent the actual behavior of shear wall apartments. Furthermore, it is very excellent since it can represent the asymmetry of the structure.