• Korean Journal of Optics and Photonics
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• v.18 no.6
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• pp.452-460
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• 2007

Ultra-low loss ZERODUR and fused silica mirrors were manufactured and their light scattering characteristics were investigated. For this purpose, ZERODUR and fused silica substrates were super-polished by the bowl feed method. The surface roughness were 0.292 ${\AA}$ and 0.326 ${\AA}$ in rms for ZERODUR and fused silica, respectively. To obtain the high reflectivity, 22 thin film layers of $SiO_2$ and $Ta_2O_5$ were deposited by Ion Beam Sputtering. The measured light scattering of ZERODUR and fused silica mirror were 30.9 ppm and 4.6 ppm, respectively. This shows that the substrate surface roughness is not the only parameter which determines the light scattering of the mirror. In order to investigate the mechanism for additional light scattering of the ZERODUR mirror, the surface roughness of the mirror was measured by AFM and was found to be 2.3 times higher than that of the fused silica mirror. It is believed that there is some mismatch at the interface between the substrate and the first thin film layer which leads to the increased mirror surface roughness. To clarify this, the contact angle measurements were performed by SEO 300A, based on the Giriflaco-Good-Fowkes-Young method. The fused silica substrates with 0.46 ${\AA}$ in its physical surface roughness shows lower contact angle than that of the ZERODUR substrate with 0.31 ${\AA}$. This indicates that the thin film surface roughness is determined by not only its surface roughness but also the surface energy of the substrate, which depends on the chemical composition or crystalline orientation of the materials. The surface energy of each substrate was calculated from a contact angle measurement, and it shows that the higher the surface energy of the substrate, the better the surface roughness of the thin film.

• The Journal of the Petrological Society of Korea
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• v.21 no.4
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• pp.385-396
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• 2012

Jeju island is the biggest volcanic island in Korea and there are over 455 Quaternary monogenetic volcanoes, of which approximately 373 volcanoes(82.0%) are cinder cones. Other volcanic forms in the island include sharp-pointed lava cone without crater(9 volcanoes; 2.0%), shield volcanoes(27 volcanoes; 5.9%), tuff rings(17 volcanoes; 3.7%), tuff cones(3 volcanoes; 0.7%), a maar(1 volcano; 0.2%) and lava domes(25 volcanoes; 5.5%). The monogenetic volcanoes include 15 small nested cinder cones(aloreum). The monogenetic volcanoes are more abundant in the eastern part of the island than in the western part. If the main cause of the weathering such as precipitation affected the shape of the monogenetic volcanoes, more monogenetic volcanoes(BC, CC, DC, etc.) are supposed to be present in the southern part that have more precipitation than in the northern part. But the distribution of the monogenetic volcanoes shows no difference between the southern and the northern parts. So we suggest that the difference of the climatic conditions did not affect the distribution or the shape of cinder cones. Tuff rings, tuff cones and a maar are distributed beneath the island or in the low-altitude areas along the shore although cinder cones are distributed in the interior of the island. This means that the volcanic activity which formed the monogenetic volcanoes resulted from either phreatomagmatic eruption or magmatic (hawaiian or strombolian) eruptions depending on the reaction with water (underground water or shallow waters). The distribution of the monogenetic volcanoes according to the altitude shows that 253(55.6%) volcanoes occur in low-lying coastal areas at an altitude below 300 m, 110(24.2%) in a middle mountainous area at an altitude between 300~600 m and 92(20.2%) in a high mountainous area at an altitude above 600 m. So more than half of monogenetic volcanoes are distributed in low-lying coastal areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.215-221
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• 1984

To investigate stability for the quality of selected ginseng products, their sorption properties were clarified in red ginseng extract(RGEP), and red ginseng extract powder(RGEP), and red ginseng extract tea(RGET). Simultaneously, the BET monolayer value of each product was determined in order to inquire out the possibility of establishment as a criterion for the optimum moisture content of the ginseng products. Based on the BET monolayer moisture level of spray dried RGEP which ranged from 4.08 to 4.65%, it would be desirable to establish the optimum moisture content of the products at 4.4${\pm}$0.3%. This is 1.3 to 1.9% lower than the criter on, "less than 6.0%". The optimum moisture level for RGET of which monolayer value ranged 0.93 to 1.37% would be 1.2${\pm}$0.17%. In this case, the maximum permissible limit of moisture content could presumably be raised up to 1.37% in place of current criterion, "less than l.2%". From the results of a study on the growth of molds, the optimum moisture content for RGE assumed to be extended up to 40.0${\pm}$1.07 despite 36.0${\pm}$1.0% of the present criterion. On the other hand, a storage study under the maltreated condition, $48{\pm}2^{\circ}C$ 75%RH, was also carried out in order to make it clear whether the BET monolayer values were able to be used as indices for optimum moisture level of the products. In all samples tested adsorption occurred at even higher levels of moisture than the monolayer values. However, since there are many other possible factors affecting the quality of products the optimum moisture content is preferable to be reduced to the monolayer value. As a result, it was proved that the optimum level of moisture for both RGEP and RGET could be established by the monolayer values.

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.30-36
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• 2001

Object: Diurnal variation is included in the diagnostic criteria of the major depressive disorder, melancholic specifier. But there has been controversy over whether diurnal variation is an unique depressive symptoms or a symptom related to a change of sleep patterns, or that of another mechanism, when the previous studies are reviewed. We investigated the existence of diurnal variation according to the subtype of depression and whether diurnal variation is charateristic of melancholic depression or not. We also compared sleep variables according to the existence of diurnal variation. Method: We examined diurnal variation, sleep patterns, severity of depression using the Visual Analogue Mood Scale, Pittsburgh Sleep Quality Index, and Hamilton Depression Rating Scale. Patients recorded their mood state on the Visual Analogue Mood Scale twice a day, morning and evening, for diurnal variation. We divided depressive patients into two groups,-diurnal variation group and nondiurnal variation group,-and compared the mood and sleep variables using SPSS. Results: The frequency of diurnal variation is not significantly different among the subtypes of depression. Significant differences between the diurnal variation group and the nondiurnal variation group existed in middle insomnia and sleep time (p<0.05). In melancholic type, al significant difference between the diurnal variation group and the nondiurnal variation group was noticed in PSQI total, sleep latency, sleep disturbances, daytime dysfunction as well as middle insomnia and sleep time (p<0.05). Conclusions: Diurnal variation existed in other types of depression as well as melancholic type. The results showed that diurnal variation was not a specific symptom of melancholic type, and existence of diurnal variation might be related to sleep patterns.

• The Journal of the Petrological Society of Korea
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• v.17 no.1
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• pp.16-35
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• 2008

We study metamorphism of metasedimetary rocks and origin and evolution of leucogranite form Samcheok area, northeastern Yeongnam massif, South Korea. Metamorphic rocks in this area are composed of metasedimentary migmatite, biotite granitic gneiss and leucogranite. Metasedimentary rocks, which refer to major element feature of siliclastic sediment, are divided into two metamorphic zones based on mineral assemblages, garnet and sillimanite zones. According to petrogenetic grid of mineral assemblages, metamorhpic P-T conditions are $740{\sim}800^{\circ}C$ at $4.8{\sim}5.8\;kbar$ in the garnet zone and $640-760^{\circ}C$ at 2.5-4.5kbar in sillimanite zone. The leucogranite (Imwon leucogranite) is peraluminous granite which has high alumina index (A/CNK=1.31-1.93) and positive discriminant factor value (DF > 0). Thus, leucogranite is S-type granite generated from metasedimentary rocks. Major and trace element diagram ($R_1-R_2$ diagram and Rb vs. Y+Nb etc.) show collisional environment such as syn-collisional or volcanic arc granite. Because Rb/sr ratio (1.8-22.9) of leucogranites is higher than Sr/Ba ratio (0.21-0.79), leucogranite would be derived from muscovite dehydrate melting in metasedimentary rocks. Leucogranites have lower concentration of LREE and Eu and similar that of HREE relative to metasedimentary rocks. To examine difference of REEs between leucogranites and metasedimentary rocks, we perform modeling using volume percentage of a leucogranite and a metasedimenatry rock from study area and REE data of minerals from rhyolite (Nash and Crecraft, 1985) and melanosome of migmatite (Bea et al., 1994). Resultants of modeling indicate that LREE and HREE are controlled by monazites and garnet, respectively, although zircon is estimated HREE dominant in some leucogranite without garnet. Because there are many inclusions of accessary phases such as monazite and zircon in biotites from metasedimentary rocks. leucogranitic magma was mainly derived from muscovite-breakdown in metasedimenary rocks. Leucogranites can be subdivided into two types in compliance with Eu anomaly of chondrite nomalized REE pattern; the one of negative Eu anomaly is type I and the other is type II. Leucogranites have lower Eu concetnrations than that of metasedimenary rocks and similar that of both type. REE modeling suggest that this difference of Eu value is due to that of components of feldspars in both leucogranite and metasedimentary rock. The tendency of major ($K_2O$ and $Na_2O$) and face elements (Eu, Rb, Sr and Ba) of leucogranites also indicate that source magma of these two types was developed by anatexis experienced strong fractionation of alkali-feldspar. Conclusionally, leucogranites in this area are products of melts which was generated by muscovite-breakdown of metasedimenary rock in environment of continetal collision during high temperature/pressure metamorphism and then was fractionated and crystallized after extraction from source rock.

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1306-1315
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• 1996

This study reviewed the changes of hemodynamlcs and centrAl pulmonary artery dimension in 54 patients who underwent bidirectional cavopulmonary shunt(BCPS) between February 1992 and December 1995 at Seoul National University Childrell's Hospital. Ag and body weight of patients averaged 36.8 $\pm$ 37.7 months and 8.0$\pm$3.0 kg, respectively Eightynine percent of patients had more than 2 violations of the risk factors for Fontan operation, resulting overall hospital mortality of 16.6%(9154). Serial hemodynamic and anglographic examinations before and mean 16.3 $\pm$ 14.3 months iirter BCPS were compared. The arterial oxygen saturation improved from a preoperative value of 71 9: 10.1 % to 79.H $\pm$ 8. 5% (n:4), p<0.05). The values of arterial oxygen saturation were lower as the age of the patients with BCPS in place was older(n=22, R'=0.341, p=0.004). A mean pulmonary artery pressure and pulmonary vascular resistance reduced from 31 $\pm$17 to 1).5$\pm$3.SmmHg(n=22, p<0.05) and from ).2$\pm$2.1 to 2.3$\pm$2.7 unit (n=7. p>0.05), respectively. Follow-up study showed a significant Increase of absolute values of ipsilateral pulmoanry artery (n: 14, p<0.05), but no change of contralateral pulmonary artreries (n: 14. p=not significant(HSI). However, there w re significant decreases in diameters of both ipsilateral and contralateral pulmonary arteries standardized by patients' body surface areas(16.8% decrease, n: 14, p< 0. 05 for ipsilatreal, 25.1%, n=14, p<0.05 for contralateral). Pulmonary artery indices for cross sectional areas of both pulmonary arterises decreased 9.3 $\pm$ 13.8% with showing a trend of more decrease as the follow-up duration was longer, We conclude that the bidirectional cavopulmonary shunt provide an excellent.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.1
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• pp.48-59
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• 2023

Ground-level ozone affects human health and plant growth. Ozone is produced by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) from anthropogenic and biogenic sources. In this study, two different land cover and emission factor datasets were input to the MEGAN v2.1 emission model to examine how these parameters contribute to the biogenic emissions and ozone production. Four input sensitivity scenarios (A, B, C and D) were generated from land cover and vegetation emission factors combination. The effects of BVOCs emissions by scenario were also investigated. From air quality modeling result using CAMx, maximum 1 hour ozone concentrations were estimated 62 ppb, 60 ppb, 68 ppb, 65 ppb, 55 ppb for scenarios A, B, C, D and E, respectively. For maximum 8 hour ozone concentration, 57 ppb, 56 ppb, 63 ppb, 60 ppb, and 53 ppb were estimated by scenario. The minimum difference by land cover was up to 25 ppb and by emission factor that was up to 35 ppb. From the modeling performance evaluation using ground ozone measurement over the six regions (East Seoul, West Seoul, Incheon, Namyangju, Wonju, and Daegu), the model performed well in terms of the correlation coefficient (0.6 to 0.82). For the 4 urban regions (East Seoul, West Seoul, Incheon, and Namyangju), ozone simulations were not quite sensitive to the change of BVOC emissions. For rural regions (Wonju and Daegu) , however, BVOC emission affected ozone concentration much more than previously mentioned regions, especially in case of scenario C. This implies the importance of biogenic emissions on ozone production over the sub-urban to rural regions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.603-614
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• 2008

End-uses of household water have been changed by a life style, housing type, weather, water rate and water supply facilities etc. and those variables can be considered as an internal and exogenous factors to estimate long-term demand forecasts. Analysis of influential factors on water consumption in households would give an explanation to cause on the change of trend and would help predicting the water demand of end-use in household. The purpose of this study is to analyze the demand trends and patterns of household water uses by metering and questionnaire such as occupation, revenue, numbers of family member, housing types, age, floor area and installation of water saving device, etc. The peak water uses were shown at Saturday among weekdays and July in a year based on the analysis results of water use pattern. A steep increase of total water volume can be found in the analysis of water demand trend according to temperature from $-14^{\circ}C$ to $0^{\circ}C$, while there are no significant variations in the phase of more than $0^{\circ}C$, with an almost stable demand. Washbowl water shows the highest and toilet water shows the lowest relation with temperature in correlation analysis results. In the results of ANOVA to find the significant difference in each unit water use by exogenous factors such as housing type, occupation, number of generation, residential area and income et al., difference was shown in bathtub water by housing type and shown in kitchen, toilet and miscellaneous water by numbers of resident. Especially, definite differences in components except washbowl and bathtub water, could be found by numbers of resident. Based on the result, average residents in a house should be carefully considered and the results can be applied as reference information, in decision making process for predicting water demand and establishing water conservation policy. It is expected that these can be used as design factors in planning stage for water and wastewater facilities.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.6
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• pp.109-120
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• 2023

The High-Frequency Radar (HFR) is an equipment designed to measure real-time surface ocean currents in broad maritime areas.It emits radio waves at a specific frequency (HF) towards the sea surface and analyzes the backscattered waves to measure surface current vectors (Crombie, 1955; Barrick, 1972).The Seasonde HF Radar from Codar, utilized in this study, determines the speed and location of radial currents by analyzing the Bragg peak intensity of transmitted and received waves from an omnidirectional antenna and employing the Multiple Signal Classification (MUSIC) algorithm. The generated currents are initially considered ideal patterns without taking into account the characteristics of the observed electromagnetic wave propagation environment. To correct this, Antenna Pattern Measurement (APM) is performed, measuring the strength of signals at various positions received by the antenna and calculating the corrected measured vector to radial currents.The APM principle involves modifying the position and phase information of the currents based on the measured signal strength at each location. Typically, experiments are conducted by installing an antenna on a ship (Kim et al., 2022). However, using a ship introduces various environmental constraints, such as weather conditions and maritime situations. To reduce dependence on maritime conditions and enhance economic efficiency, this study explores the possibility of using unmanned aerial vehicles (drones) for APM. The research conducted APM experiments using a high-frequency radar installed at Dangsa Lighthouse in Dangsa-ri, Wando County, Jeollanam-do. The study compared and analyzed the results of APM experiments using ships and drones, utilizing the calculated radial currents and surface current fields obtained from each experiment.

• Journal of Korean Academy of Nursing
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• v.20 no.2
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• pp.153-173
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• 1990

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 healthy development of the child and the wellbeing of the whole family. Nurses assess the quality of the behavioral characteristics of the maternal-infant interaction. This study examined the relationships between primiparas pereptions of their delivery experience and their maternal infant interaction. It compared to delivery experience of mothers having a normal vaginal delivery with those having a casearean section. The purpose was to explore the relationships between the mother's perceptions of her delivery experience with her maternal infant interaction. The aim was to contribute to the development of theoretical understanding on which to base care toward promoting the quality of maternal-infant interaction. Data were collected directly by the investigator and a trained associate from Dec. 1, 1987 to March 8, 1988. Subjects were 3 random sample of 62 mothers, 32 who had a normal vaginal delivery and 30 who had a non-elective cesarean section (but without other perinatal complications) at three general hospitals in Seoul. Instruments used were the Stainton Parent -infant Interaction Scale(1981) and the Marut and Mercer Perception of Birth Scale(1979). The first observations were made in the delivery room (for vaginally delivered mothers only), followed by day 1, day 2, day 3, and 2 weeks, 4 weeks, 6 weeks and 8 weeks after birth, for a total of 7-8 contacts(Cesarean section mothers were observed on days 4 and 5 but the data not used for analysis). 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 done by computer using as SPSS program and indulded X² test, paired t-test, t-test, and Pearson Correlation coefficient ; the results were as follows. 1. Mothers who had a normal vaginal delivery tended to perceive the delivery experience more positively than cesarean section mothers(p＝0.002). The finding supported the hypothesis I that perception of delivery would vary according to the method of delivery. Mothers' perceptions of birth were classified into three dimensions, labor, delivery and the bady. There was a significantly different and positive perception by the vaginally delivered mothers to the delivery experience(p＝0.000) but no differences for labor or the bady according to the delivery method(p＝0.096, p＝0.389), 2. Mothers who had a normal vaginal delivery had higher average maternal-infant interaction scores(p＝0.029) than mothers who had a cesarean section. There were similar higher scores for the 1st day(p＝0.042), 2nd day (p＝0.009), and the 3rd day(p＝0.006) after delivery but not for later times. The findings supported the hypothesis Ⅱ that there would be differences in maternal-infant interaction for mothers having vaginal and cesarean section deliveries. However these differences deccreased section deliveries. However these differences decreased over time . by eight weeks the scores for vaginal delivery mothers averaged 8.1 and for cesarean section mothers, 7.9. 3. The more highly positive the pereption of the delivery experience, the higher the maternal-infant interaction score for all subjects(F＝.3206, p＝.006). The findings supported the hypothesis Ⅲ that there would be correlations between perceptions of delivery and maternal-infant interaction. The maternal infant interaction was highest when the perception of the bady and deliery was positive(r＝.4363, p＝.000, r＝.2881, p＝.012). No correlations between perceptions of labor and maternal-infant interaction were found(p＝0.062). 4. The daily maternal-infant interaction score for the initial contact after birth to 8 weeks postpartum had the lowest average score 5.20 and the highest 7.98(in a range of 0-10). This subjects group of mothers needed nursing intervention to promote their maternal- infant interaction. The daily scores for the maternal-infant 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 after birth(P＝0.000). 5. When the eight items of maternal-infant interaction were evaluated separately, “Expresses feelings about her role as mother” had the highest average score, 1.64(ina range of 0-3)and “Speaks to baby” the lowest, 0.9. All items, with the possible exception of “Expresses feelings about her role as mother”, suggested the subjects' need of nursing intervention to promote maternal-infant interaction. 6. There were positive correlations between certain general charateristis, namely, both a higher economic status(p＝0.002) and breast feeding(p＝0.202) and maternal - infant interaction. There were positive correlations between a mother's confidence in her role as a mother and the perception of the birth experience(p＝0.004). For mothers who had a cesarean section, a positive perception of the birth experience was related to the duration of her marriage(p＝0.010), a wanted pregnancy (P＝0.030) and her confidence in her role as a mother(p＝0.000). Pereptions of birth for mothers who had a normal vaginal delivery were positive than those for mothers who had a cesarean section. The level of maternalinfant interaction for mothers delivered vaginally was higher than for cesarean section mothers. The relationship between perception of birth and materanalinfant interaction was confirmed. Cesarean section has an impact on the mother's perceived experience of birth which, in turn, is positively related to maternal-infant in turn, is positively related to maternal-infant interaction. Nursing intervention to enhance maternal-infant interaction should begin in prenatal classes with an exploration of the potential impact of cesarean section on the perceptions of the birth experience and continue throughout the perinatal and post-natal periods to promote the mother's ability to control with this crisis experience and to mobilize social support. Nursing should help transform a relatively negatively perceived experience into an accepted, positively perceived and self affirming experience which enhances the maternal-infant relationship.