• Journal of Korea Water Resources Association
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• v.34 no.6
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• pp.659-672
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• 2001

Generally, design flood for a hydraulic structure is estimated using statistical analysis of runoff data. However, due to the lack of runoff data, it is difficult that the statistical method is applied for estimation of design flood. In this case, the synthetic unit hydrograph method is used generally and the models such as NYMO method, Snyder method, SCS method, and HYMO method have been widely used in Korea. In this study, these methods and KICT method, which is developed in year 2000, are compared and analyzed in 10 study areas. Firstly, peak flow and peak time of representative unit hydrograph and synthetic unit hydrograph in study area are compared, and secondly, the shape of unit hydrograph is compared using a root mean square error(RMSE). In Nakayasu method developed in Japan, synthetic unit hydrograph is very different from peak flow, peak time, and the shape of representative unit hydrograph, and KICT method(2000) is superior to others. Also, KICT method(2000) is superior to others in the aspects of using hydrologic and topographical data. Therefore, Nakayasu method is not a proper in hydrological practice. Moreover, it is considered that KICT model is a better method for the estimation of design flood. However, if other model, i.e. SCS method, Nakayasu method, and HYMO method, is used, parameters or regression equations must be adjusted by analysis of real data in Korea.

• Food Science and Preservation
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• v.14 no.4
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• pp.414-418
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• 2007

The physicochemical characteristics and sensory properties of Deodeok wine, formed by leaching of Deodeok at room temperature for 180 days, were investigated over the following range of Deodeok levels: 10, 15 and 20% (all w/v). The higher the level of Deodeok, the greater were the final values of total sugars, reducing sugars, total polyphenols, and crude saponins. The Hunter's b-value (yellowness) of Deodeok wine varied markedly with Deodeok levels, and yellowness was highest in Deodeok wine containing 20% (w/v) Deodeok. Non-volatile compounds, that form the basis of the liquor tax law, were 0.64, 1.38 and 2.11% (all w/v), respectively, at day 160. Of these values, that of 2.11% (w/v), the level of non-volatile compounds in Deodeok wine containing 20% (w/v) Deodeok, was in accord with the liquor tax law (that requires this figure to be 2.0%). Sensory evaluation showed that Deodeok wine containing 20% (w/v) Deodeok was superior to the other wines tested.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4102-4110
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• 2022

Aiming at high-power and long-pulse operation up to 1000 s, some improvements have been made for both 2.45 GHz and 4.6 GHz lower hybrid (LH) systems during the recent 5 years. At first, the guard limiters of the LH antennas with graphite tiles were upgraded to tungsten, the most promising material for plasma facing components in nuclear fusion devices. These new guard limiters can operate at a peak power density of 12.9 MW/m². Strong hot spots were usually observed on the old graphite limiters when 4.6 GHz system operated with power >2.0 MW [B. N. Wan et al., Nucl. Fusion 57 (2017) 102019], leading to a reduction of the maximum power capability. With the new limiters, 4.6 GHz LH system, the main current drive (CD) and electron heating tool for EAST, can be operated with power >2.5 MW routinely. Long-pulse operation up to 100 s with 4.6 GHz LH power of 2.4 MW was achieved in 2021 and the maximal temperature on the guard limiters measured by an infrared (IR) camera was about 540 ℃, much below the permissible value of tungsten material (~1200 ℃). A discharge with a duration of 1056 s was achieved and the 4.6 GHz LH energy injected into the plasma was up to 1.05 GJ. Secondly, the fully-active-multijunction (FAM) launcher of 2.45 GHz system was upgraded to a passive-active-multijunction (PAM), for which the density of optimum coupling was relatively low (below the cut-off value). Good coupling with reflection coefficient ~3% has been achieved with plasma-antenna distance up to 11 cm for the new PAM. Finally, in order to eliminate the effect of ion cyclotron range of frequencies (ICRF) wave on 4.6 GHz LH wave coupling, the location of the ICRF launcher was changed to a port that is located 157.5° toroidally from the 4.6 GHz LH system and is not magnetically connected.

• Research in Community and Public Health Nursing
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• v.12 no.2
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• pp.450-458
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• 2001

Purpose: The purpose of this study was to establish a structural equation model on social roles and health for married working mothers. to determine the effects of social roles on Korean women's health and to explore the mediating role of self-esteem in the relationship between social roles qualities and health. Method Data were collected from 323 employed women with partner and children. lived in Seoul and near Seoul. Response rate was 62.3%. The instruments for measurements were Role Quality Scale developed by Park et al. (1999). Rosenberg's Self-Esteem Scale. and 31 items from SF-36 developed by Ware & Sherboune(l992). Results: The effect of marital role quality on self-esteem and the effect of parental role quality on health were not significant. Modification model fitted with the collected data very well. as evidenced by the small chi-square(0.58), the very high goodness-of-fit(GFI = 1.00), and adjusted goodness-of-fit (AGFI = 0.99), and very small root mean square residual(RMSR=0.0072), and the slope of Q-plot is over 1. 41% of the variance in self-esteem and 21% of the variance in health were accounted for by these variables. Conclusion: Further research concerned with the mediating effects of self-esteem in the role and health relationship should be covered the issue of various role combinations. And it is necessary to examine the influence of subfactor of quality of social roles on health.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.109-116
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• 1997

Purpose : Chronic renal failure is often accompanied by severe dyslipidemia, a known risk factor for cardiovascular disease. Lipoprotein(a) [Lp(a)] has recently been characterized as a risk factor for atherosclerosis and thrombosis. Cardiovascular disease is the leading cause of death in adult patients on dialysis. However, there are only limited data available concerning risk factors for atherosclerosis in uremic children. We have measured serum levels of lipids, lipoproteins, apolipoproteins and Lp(a) in uremic children with maintenance dialysis. Methods : Ten uremic children with hemodialysis (HD) and 14 with peritoneal dialysis (PD) in our dialysis unit were included in this study. The mean age of HD patients was $162{\pm}59$ months and the male to female ratio was 7:3. The mean age and sex ratio of PD patients were $123{\pm}63$ months and 6:8, respectively. The levels of cholesterol, triglyceride, lipoproteins, apolipoproteins and Lp(a) were measured from serum sampled after 14 hours of fasting. The normal control levels were cited from 2 articles presenting the normal blood lipid and lipoprotein levels of primary school and middle school children in Korea. Results : There was no difference in age, sex ratio, body mass index and duration of dialysis between the HD and the PD group. The serum concentration of the cholesterol, triglyceride and apolipoprotein B were significantly elevated in dialysis patients compared with normal subjects. The serum level of Lp(a) was significantly elevated in only PD group. The serum Lp(a) level was below 30 mg/dl in 13 and above 30 mg/dl in 11 patients. The serum albumin level was significantly decreased in high Lp(a) group than in low Lp(a) group. Conclusion : The uremic children receiving dialysis reveal abnormal serum lipid and lipoprotein profiles. These results suggest that they have a higher risk for coronary heart disease, although there has been no clinical evidence of coronary heart disease at present. A long-term follow-up study of these children to clarify the suggestion should be started now.

• 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.