• Journal of Astronomy and Space Sciences
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• v.26 no.3
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• pp.305-316
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• 2009

In this study, we suggest an empirical forecast of CIR (Corotating Interaction Regions) and geomagnetic storm based on the information of coronal holes (CH). For this we used CH data obtained from He I $10830{\AA}$ maps at National Solar Observatory-Kitt Peak from January 1996 to November 2003 and the CIR and storm data that Choi et al. (2009) identified. Considering the relationship among coronal holes, CIRs, and geomagnetic storms (Choi et al. 2009), we propose the criteria for geoeffective coronal holes; the center of CH is located between $N40^{\circ}$ and $S40^{\circ}$ and between $E40^{\circ}$ and $W20^{\circ}$, and its area in percentage of solar hemispheric area is larger than the following areas: (1) case 1: 0.36%, (2) case 2: 0.66%, (3) case 3: 0.36% for 1996-2000, and 0.66% for 2001-2003. Then we present contingency tables between prediction and observation for three cases and their dependence on solar cycle phase. From the contingency tables, we determined several statistical parameters for forecast evaluation such as PODy (the probability of detection yes), FAR (the false alarm ratio), Bias (the ratio of "yes" predictions to "yes" observations) and CSI (critical success index). Considering the importance of PODy and CSI, we found that the best criterion is case 3; CH-CIR: PODy=0.77, FAR=0.66, Bias=2.28, CSI=0.30. CH-storm: PODy=0.81, FAR=0.84, Bias=5.00, CSI=0.16. It is also found that the parameters after the solar maximum are much better than those before the solar maximum. Our results show that the forecasting of CIR based on coronal hole information is meaningful but the forecast of goemagnetic storm is challenging.

• Journal of Nutrition and Health
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• v.48 no.3
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• pp.289-297
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• 2015

Purpose: This study was conducted in order to determine the difference of Importance and Performance Related service management and feeding practices of teachers at mealtime in childcare centers. Methods: In December, 2013, questionnaires were completed by teachers working at childcare centers in Geumcheon-gu, Seoul. A total of 179 teachers responded to questions regarding perceived importance and degree of performing related service management and feeding practices at mealtime in childcare centers. Factor analysis and Importance-Performance Analysis (IPA) were used. Results: Four factors including 11 items were represented by factor analysis: 'Personal hygiene management', 'Feeding practice', 'Food material management', and 'Service at serving foods'. For 'Personal hygiene management', scores for perception on importance and performance were 4.42 and 3.84 points of 5 that were the lowest among factors. As a result of IPA, teachers were aware of the importance and performed well, 'Encouraging and praising children's eating habits at mealtime', 'Giving thanks before and after a meal', and 'Sitting and eating with children at mealtime' belonged to 'Feeding practice'; whereas they were not aware of the importance and performed insufficiently, 'Wearing the hygiene hat for serving foods', 'Wearing disposable gloves for serving foods', and 'Wearing the apron for serving foods' belonged to 'Personal hygiene management'. Conclusion: For children's health and safety in foodservice at childcare centers, personal hygiene management is very important when cooking as well as serving food. The results suggest that education targeting personal hygiene management is necessary for management of hygiene by teachers while serving food in childcare centers. In addition, guidelines on service management and feeding practice are needed for teachers working at childcare centers.

• Journal of Nutrition and Health
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• v.42 no.3
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• pp.246-255
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• 2009

The development of food frequency questionnaire (FFQ) is based on food use and/or dish use. Regardless of potential effect of oils and seasonings on chronic diseases, most of food-based FFQs do not include oils and seasonings in calculation of nutrient intake. This study examined the effect of added (seasoning) oils and seasonings on the distribution of subjects by relative nutrient intake using a dish-based FFQ. The subjects were 1,303 persons (men 478, women 825) aged over 20 years old, who completed FFQ composed of 121 items. Three types of daily nutrient intake were calculated; 1) total nutrient intake with oils and seasonings, 2) nutrient intake without oils, and 3) nutrient intake without oils and seasonings. The correlation and agreement of classification of subjects by relative nutrient intake were examined. All analyses were performed using absolute nutrient intakes and total energy-adjusted nutrient intakes by residual method. Comparing total nutrient intake with the nutrient intake without oils, energy, vegetable fat and vitamin E intake were significantly decreased and kappa values were 0.95 (${\kappa}{\omega}$ = 0.98), 0.64 (${\kappa}{\omega}$ = 0.81), and 0.59 (${\kappa}{\omega}$ = 0.79), respectively. Comparing total nutrient intake with the nutrient intake without oils and seasonings, most of nutrients intake except animal fat, animal protein, retinol and cholesterol were significantly decreased, and kappa values of vegetable fat (${\kappa}$ = 0.64, ${\kappa}{\omega}$ = 0.81), vitamin E (${\kappa}$ = 0.59, ${\kappa}{\omega}$ = 0.79) and sodium (${\kappa}$ = 0.61, ${\kappa}{\omega}$ = 0.80) were under 0.80. After total energy was adjusted, agreement was lower than before total energy adjustment. Excluding oils and seasonings to assess nutrient intake underestimated vegetable fat, vitamin E and sodium intake and affected the distribution of subjects by their relative nutrient intake. Therefore, we suggest that research focused on these nutrients need to be cautious about the interpretation of the results.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.1
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• pp.98-107
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• 2013

Big and old trees in the scenic spots with the attributes of remote villas are vulnerable to man-made damages and very sensitive to the external environment such as soil conditions, so the corresponding management plans are required. Thus this study has been conducted to survey the big and old trees in the scenic remote villas and suggest the ideal management plans. The results can be summarized as follows. First, regarding the tree heath above the ground, transformation of tree, death of branches, and death of barks are closely related to tree vigor. Particularly, the areas receiving many visitors require prompt countermeasures against the dried and dead tress above the ground and the areas in which dried and dead tress occurred and also the safety measures for the visitors and facilities. Second, regarding the soil environment, visitor traffic is closely related to the tree vigor. In 15 remote villa gardens, 64% of trees are exposed to heavy traffic and the tree vigor has declined due to an increase of visitor. Thus, there is a need to give positive consideration the installation of the complementary facilities and the plantation of herbal plants in the congested areas to form the ground surface that can tolerate the heavy visitor traffic. Third, remote gardens are in general located adjacent to ponds and mountain streams and thus the trees in the waterfront areas require the prompt countermeasures against the decline of growth due to the excess-moisture in the soil. Further the blockage of the sewage system due to the heavy rains dampens the surrounding soil, which results in lethal damages to the trees. Thus, there is a need of the maintenance of the waterfront areas and sewage system before and after the rainy season. In addition, there is a need to establish medium-long term management polices through the recognition of the importance of the main trees of remote villa gardens in scenic spots and prepare the tree management manual depending on the attributes of the corresponding areas. I strongly suggest making manuals for the systematic management as well as the extensive PR activities and education for the preservation of tress on a long-term basis; and furthermore securing the budget and manpower for the research and development of a systematic management system.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.2
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• pp.87-91
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• 2015

As negative effects of climate change have been visualized and its direct damages to economy have been realized, the global efforts to respond to climate change by reducing greenhouse gas emission were accelerated. Korea's Carbon Footprint Labeling gets a lot of attention as one of the effective methods to contribute to national GHG reduction goal, and for enterprises to show customers how much effort the company put into global warming prevention. Consumers' interest on low-carbon products has been increasing. This study uses Life Cycle Assessment method to calculate the amount of carbon emission of dishwashing detergent, LG Household & Healthcare, which reduced carbon emissions by using raw materials that has relatively lower environment load. Life Cycle Assessment Method is based on guidelines of Carbon Footprint Labeling, Ministry of Environment, and pre-manufacturing, manufacturing, and disposal phase are included while use phase of the product is excluded from assessment. In order to understand the effects of eco-design on carbon emissions, the dishwashing detergent's carbon emissions are compared before and after the change of main raw materials. The result shows the improvement from $0.47kgCO_2eq/kg$ to $0.38kgCO_2eq/kg$ per product, and this means the main raw materials' carbon emissions could be reduced by around 9.4%, which is equivalent to 916tons of GHG emissions per year.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.347-352
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• 1996

These experiments were conducted to monitor the change in $NO_3{^-}-N$ in a plastic film house where $NO_3{^-}-N$ have been accumulated in the soil of high level (about 370 mg/kg) The objective of this study was to obtain the information needed to establish the N Fertilizer recommendation based on the available N content in the soil for vegetable cultivation. The cultivated crops were chinese cabbage in the spring, lettuce in the summer, and chinese cabbage in the autumn. The crops were cultivated with and without N application. The concentration of $NO_3{^-}-N$ in the soil was analysed before and after the cultivation of each crop. When $NO_3{^-}-N$ in the soil is as high as 370 mg/kg. even without N application, the yield of the first season crop, cabbage in the spring was 175 ton/ha and that of second season crop, lettuce in the summer was 53 ton/ha. These yields were comparable with those obtained under the application of N fertilizer: meaning that no N application would be needed for those crops when $NO_3{^-}-N$ in the soil is as high as 370 mg/kg. The yield of third crop, cabbage in the autumn was higher under N application than that under no N application by 62%. The fate of $NO_3{^-}-N$ in the soil differed along with the crop sequence. In the first crop, 14.5% was absorbed by crop, 25.4% remained in the soil and 60.1% was unaccounted for. In the second season, 25.3% was absorbed by crop, 51.8% remained in the soil and 22.9% was unaccounted for. In the third crop, 62.8% was absorbed by crop, 19.4% remained in the soil and 16.8% was unaccounted for.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.547-561
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• 1998

Obstructive sleep apnea (OSA) is a disorder characterized by repetitive episode of upper airway collapse during sleep. Recent studies showed that not only the anatomic factors but the physiologic factors of the upper airway also have effcts on the occurrence of apnea and that the genioglossus muscle also plays an important role in the maintenance of the upper airway. A variety of therapies were performed to treat OSA, and among them the use of mandibular repositioning appliances showed reasonable results. But there is still a lack of research on the structural and physiological mechanism upon the use of mandibular repositioning appliances. The author selected 26(male 17, female 9) OSA patients that came to the Yonsei University Dental Hospital, Department of Orthodontics, and 20 normal adults (male 10, female 10) and took cephalometric radiographs of them in a supine position before and after the placement of the mandibular repositioning appliance to see the structural changes of the upper airway and compare the therapeutic effects between the two groups. We also studied the waking genioglossus muscle activity in OSA patients and investigated the difference in the electromyogram of the genioglosssus muscle upon the change in body posture and the use of mandibular repositioning appliance. Following results were obtained. 1. Among the cephalometric measurements of the upper airway structure, the length of the soft palate, maximum thickness of the soft Palate and SPAS, MAS, VAL, H-H1, MP-H showed statistically significant differences between the normal and OSA groups, but the IAS and EAS showed no statistically significant differences between the two groups. 2. In both the normal and OSA groups, as the epiglottis moved forward on wearing the mandibular repositioning appliance, the epiglottis level of the upper airway increased and the maximum thickness of the soft palate changed and the hyoid bone also moved forward, but the IAS in both groups showed various results and the effect of the mandibular repositioning appliance on the structure of the upper airway was different in the two groups. 3. Upon changing the position, the electromyogram of the genioglossus muscle showed a increasing tendency but there was no statistically significant differences, and when the mandibular repositioning appliance were worn there was a statistically significant increase in the electromyogram of the genioglossus muscle in both the upright and supine positions. The mandibular repositioning appliances not only have an effect on the anatomical structure of the upper airway but also on the physiology of the upper airway. There are different responses to the use of mandibular repositioning appliance between the normal and OSA groups therefore it could be considered to have the different physiology of the upper airway between the two groups.

• Korean Journal of Agricultural Science
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• v.3 no.2
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• pp.152-159
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• 1976

This experiment was conducted to select genotypes that were high-yielding and adapted to the soil and weather conditions in Korea, from 13 Fawn deri ved progenies which represented in the previous study. Comparisons were made in various leaf and plant characteristics, and forage productivities, between the 13 polycross progenies of high-yielding Fawn and control varieties including Fawn, Alta, and Kentucky 31. The results obtained were summarized as follow; Genetic differences between the polycross progeny group and the control group were recognized in leaf fresh weight but those between two groups in leaf dry weight were not observed. Leaf area of all derived progenies and control varieties were appeared to have individual genetic differences and, moreover, the leaf area of the polycross progeny group was larger than that of the control. Differences between polycross progeny group and control group in leaf width were not significant. However, leaf length exhibited significant differences among all polycross progenies, and control varieties between two groups, and among polycross progenies but no differences were observed among control varieties. Tiller number, plant height, and plant width of the polycross progeny group were larger than those of the control varieties when measured before and after harvest. Panicle length among all polycross progenies and control varieties showed minor differences. However, significant differences were found between the polycross progeny group and control group, as well as among the polycross progenies and control varieties within each group in culm length. Above characteritics in the leaf fresh and dry weight, area and length, plant width and height, and tiller number showed positive correlations with the forage yields, respectively. Forage yields of the polycross progenies were higher than those of the control varieties and the variation of the yields among the genotypes were great.

• Journal of dental hygiene science
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• v.3 no.1
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• pp.45-50
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• 2003

In order to develop the program of oral hygiene education for elementary school senior-students, a questionnaire survey of elementary fourth, fifth and sixth students who are under continual control program of oral hygiene. (1) For tooth brushing time, after dinner is more than before. 73.7% of respondents brushed the teeth twice or more a day. (2) 62.1% of respondents took the cariogenic food twice or more a day. (3) 90.1% of respondents had visited a dental clinic. (4) Concerning fear for dental treatment, only 14.4% had a feeling of fear. (5) Regarding the experience with a preventive treatment, 39.7% had an experience with pit and fissure sealing, and 24.2% had an experience with the application of fluorides. (6) 46.2% of respondents had a preference for the fluoride mouth rinsing program, and 38.4% wanted that program to keep going on. As to the reason to favor the fluoride mouth rinsing program, 38.2% preferred it because of prevention of dental caries, and 43.0%, the largest percentage, didn't favor it because they found it too much trouble to do. (7) Comparing with the research result in 2000, we proved positively the educational effect of brushing frequency, positive understanding and preference to water school fluoridation program, and got the negative data of experience of visiting to oral clinic and preventive treatment.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.66-78
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• 2004

The objective of this study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration in enamel and dentin achieved with those gained using the conventional technique and vibration technique. For enamel specimens, thirty teeth were sectioned mesio-distally. Sectioned two parts were assigned to same adhesive system but different treatment(vibration vs. non-vibration). Each specimen was embedded in 1-inch inner diameter PVC pipe with a acrylic resin. The buccal and lingual surfaces were placed so that the tooth and the embedding medium were at the same level. The samples were subsequently polished silicon carbide abrasive papers. Each adhesive system was applied according to its manufacture's instruction. Vibration groups were additionally vibrated for 15 seconds before curing. For dentin specimen, except removing the coronal part and placing occlusal surface at the mold level, the remaining procedures were same as enamel specimen. Resin composite(Z250. 3M. U.S.A.) was condensed on to the prepared surface in two increments using a mold kit(Ultradent Inc., U.S.A.). Each increments was light cured for 40 seconds. After 24 hours in tap water at room temperature, the specimens were thermocycled for 1000cycles. Shear bond strengths were measured with a universal testing machine(Instron 4465, England). To investigate infiltration patterns of adhesive materials, the surface of specimens was examined with scanning electron microscope. The results were as follows: 1. In enamel the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration group(group 1, 3, 5). The differences were statistically significant except AQ bond group. 2. In dentin, the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration groups(group 1, 3, 5). But the differences were not statistically significant except One-Up Bond F group. 3. The vibration group showed more mineral loss in enamel and longer resin tag and greater number of lateral branches in dentin under SEM examination.