• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6B
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• pp.709-721
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• 2008

This paper is to test the applicability of ModKIMSTORM (Modified KIneMatic Wave STOrm Runoff Model) by applying it to Namgangdam watershed of $2,293km^2$. Model inputs (DEM, land use, soil related information) were prepared in 500 m spatial resolution. Using five typhoon events (Saomi in 2000, Rusa in 2002, Maemi in 2003, Megi in 2004 and Ewiniar in 2006) and two storm events (May of 2003 and July of 2004), the model was calibrated and verified by comparing the simulated streamflow with the observed one at the outlet of the watershed. The Pearson's coefficient of determination $R^2$, Nash and Sutcliffe model efficiency E, the deviation of runoff volumes $D_v$, relative error of the peak runoff rate $EQ_p$, and absolute error of the time to peak runoff $ET_p$ showed the average value of 0.984, 0.981, 3.63%, 0.003, and 0.48 hr for 4 storms calibration and 0.937, 0.895, 8.08%, 0.138, and 0.73 hr for 3 storms verification respectively. Among the model parameters, the stream Manning's roughness coefficient was the most sensitive for peak runoff and the initial soil moisture content was highly sensitive for runoff volume fitting. We could look into the behavior of hyrologic components from the spatial results during the storm periods and get some clue for the watershed management by storms.

• Korean Journal of Pharmacognosy
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• v.54 no.2
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• pp.80-87
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• 2023

Rancidity changes were examined for 6 herbal medicines, namely Persicae Semen, Armeniacae Semen, Lini Semen, Trichosanthis Semen, Arecae Semen, Myristicae Semen known to have relatively high fat content. In order to reduce rancidity of herbal medicines, samples were stored at 3 different conditions of room, refrigerating and freezing temperatures, and the rancidity was measured for 10 months with every 2 month interval. Fat content was extracted by using ethyl ether, and acid values and peroxide values, which are generally accepted indicators of fat rancidity, were measured. When storing Persicae Semen, Lini Semen and Arecae Semen at room temperature, the acid values increased as the storage period increased, and it was higher than when stored in refrigeration or freezing. The measurement of peroxide value showed more significantly higher initial degree of rancidity when Persicae Semen, Trichosanthis Semen, Arecae Semen and Myristicae Semen were stored at room temperature. It was observed that storing herbal medicines in refrigeration or freezing inhibited their rancidity compared to storing them at room temperature. To investigate the quality changes according to rancidity, the analysis of aflatoxins and indicator components showed that aflatoxins B₁ and B₂ were detected in Armeniacae Semen, Arecae Semen and Myristicae Semen, and the amount of amygdalin was well maintained within the specification standard.

• Journal of the Korean Institute of Rural Architecture
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• v.25 no.4
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• pp.9-16
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• 2023

In this study, the status and characteristics of fine dust and its impact on neighboring areas were investigated to proactively respond to the government's environmental regulations expected in the future and to minimize the damage by the fine dust generated at construction waste intermediate treatment plants. In addition, since there are no such plants that can affect the surroundings with no houses or other waste treatment sites nearby, an independently located construction waste intermediate treatment plant was selected to compare the characteristics of fine dust with that from the construction waste intermediate treatment sites located in the downtown area. The conclusions of the study are as follows. (1) The measurement results of PM10 at 4 points in the plant showed that the location where the crushing facility was operating had an elevated level of fine dust at 80㎍/m³ on average and a maximum of 124㎍/m³, and the level rose to 110㎍/m³ at points where vehicles frequent. (2) The PM2.5 measurement results inside the plant showed that the average concentration of the reference point was 16㎍/m³ and the maximum value was 20㎍/m³, which was distributed within the management standard. (3) It was found that the average concentration of PM10 in the nearby area ranged from 28 to 38㎍/m³, which was similar to or lower than 36㎍/m³ of the reference point. Therefore, the concentration of the fine dust generated in the plant had a negligible effect on the increase in concentration of fine dust in nearby areas. (4) The heavy metal contents were measured from the filter paper collected from the plant. The PM10 was found to be about 14 to 26ng/m³, and PM 2.5 was 25 to 28ng/m³, which was the average of domestic atmospheric concentrations. (5) The SEM-EDX analysis results showed that the PM10 contained Si and O around 40% similarly for both. The SiO2, a component of silica occupied the most and C was present as CaCO3, which was assumed to be a limestone component. The remaining components included NaO, Al2O3, and CaO as trace oxides. (6) The SEM-EDX analysis results showed that the PM 2.5 contained 5 to 7% of Cl, which is a chlorine ion, and a small amount of K was detected at 2.51% in the sample from the shutdown plant.

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.83-94
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• 2024

The proportion of plant-based meat alternative (PBMA) consumers has recently increased in Korea. This is due to several reasons including protecting the environment, satisfying preferences, maintaining health, and improving eating habits. Accordingly, many companies produce and sell alternative meat using various materials. Alternative meats are classified into plant (such as soybeans and wheat), seaweed, insect, and cultured meats, depending on the raw materials used in manufacturing. PBMA is sold after undergoing processes such as grinding, seasoning, and molding. Therefore, monitoring the presence of any hazardous elements during this process is essential. Accordingly, in this study, we analyzed the harmful components of nine domestically distributed PBMA that are most easily accessible to consumers. After extracting fat from the samples and analyzing the rancidity level, samples F, G, and I were highly rancid. Trace amounts of aflatoxin were detected in samples A and B, but confirmed to be within the range. Cd and Pb were not detected in any sample. We hope that this study will help establish methods to ensure the safety of domestically sold PBMA.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.1
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• pp.77-84
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• 2024

Four children's cosmetic sets were purchased online, labeled for use from 4 years of age, and 81 components of each were analyzed for lead, cadmium, arsenic, antimony, nickel, cobalt, copper, chromium, and mercury by inductive coupled plasma - mass spectrometry (ICP - MS). The average metal concentrations were as follows: 0.82 ㎍/g for lead, 0.03 ㎍/g for cadmium, 0.97 ㎍/g for arsenic, 0.52 ㎍/g for antimony, 2.32 ㎍/g for nickel and 0.01 ㎍/g for mercury which was lower than the acceptable standards for all products. Higher mean values of lead, antimony, cobalt, and copper were detected in imported than domestic products (p < 0.05). There was a statistically significant difference in the average values of heavy metals according to the type of cosmetics (p < 0.05), with eyeshadow showing the highest mean values of arsenic 2.47 ㎍/g, nickel 6.36 ㎍/g, and chromium 11.06 ㎍/g. and the highest mean concentrations were 1.20 ㎍/g for lead, 1.17 ㎍/g for antimony, and 23.60 ㎍/g for copper in blusher. The levels of cobalt in the 81 children's cosmetics were ND ~ 5.23 ㎍/g, copper were ND ~ 379.61 ㎍/g, and chromium were detected ND ~ 36.95 ㎍/g, respectively. Brown colored cosmetics had the highest mean concentrations of nickel and cobalt. Purple-colored cosmetics had the highest mean concentration of lead and chromium.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.467-476
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• 2023

Schisandra chinensis (S. chinensis) is a deciduous broad-leaved cave plant belonging to the Schisandraceae family and is widely distributed in East Asia including Korea, Japan, China, and Taiwan. It has been reported that the main components contained in S. chinensis include lignan compounds and triterpenoid compounds. To distinguish the characteristics of S. chinensis by production region of Korea, a discriminant was established by performing metabolite profiling and principal component analysis, a multivariate statistical analysis technique. As a result, 16 types of triterpenoids, 9 types of lignan, and 1 type each of flavonoid, phenylpropanoid, and fatty acid were identified. In addition, through multivariate statistical analysis, it was confirmed that the four groups in Danyang, Moongyeong, Geochang, and Pyeongchang were divided, by applying the s-plot model of orthogonal partial least squares discriminant analysis. Biomarkers were identified: lanostane, cycloartane, schiartane triterpenoid, and dibenzocyclo-octadiene lignan were identified as chemical markers, respectively.

• Journal of Korean Society of Forest Science
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• v.90 no.2
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• pp.197-209
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• 2001

TOPMODEL, semi-distributed hydrological model, is frequently applied to predict the amount of discharge, main flow pathways and water quality in a forested catchment, especially in a spatial dimension. TOPMODEL is a kind of conceptual model, not physical one. The main concept of TOPMODEL is constituted by the topographic index and soil transmissivity. Two components can be used for predicting the surface and subsurface contributing area. This study is conducted for the validation of applicability of TOPMODEL at small forested catchments in Korea. The experimental area is located at Gwangneung forest operated by Korea Forest Research Institute, Gyeonggi-do near Seoul metropolitan. Two study catchments in this area have been working since 1979 ; one is the natural mature deciduous forest(22.0 ha) about 80 years old and the other is the planted young coniferous forest(13.6 ha) about 22 years old. The data collected during the two events in July 1995 and June 2000 at the mature deciduous forest and the three events in July 1995 and 1999, August 2000 at the young coniferous forest were used as the observed data set, respectively. The topographic index was calculated using $10m{\times}10m$ resolution raster digital elevation map(DEM). The distribution of the topographic index ranged from 2.6 to 11.1 at the deciduous and 2.7 to 16.0 at the coniferous catchment. The result of the optimization using the forecasting efficiency as the objective function showed that the model parameter, m and the mean catchment value of surface saturated transmissivity, $lnT_0$ had a high sensitivity. The values of the optimized parameters for m and InT_0 were 0.034 and 0.038; 8.672 and 9.475 at the deciduous and 0.031, 0.032 and 0.033; 5.969, 7.129 and 7.575 at the coniferous catchment, respectively. The forecasting efficiencies resulted from the simulation using the optimized parameter were comparatively high ; 0.958 and 0.909 at the deciduous and 0.825, 0.922 and 0.961 at the coniferous catchment. The observed and simulated hyeto-hydrograph shoed that the time of lag to peak coincided well. Though the total runoff and peakflow of some events showed a discrepancy between the observed and simulated output, TOPMODEL could overall predict a hydrologic output at the estimation error less than 10 %. Therefore, TOPMODEL is useful tool for the prediction of runoff at an ungaged forested catchment in Korea.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.345-354
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• 2013

To understand the community structures of the vegetation of the beaches and coastal dunes of Seocheon-gun, Boryeong-si, Anmyeon-do, Taean-gun in Chungcheongnam-do and Buan-gun in Jeollabuk-do at the west coast of South Korea, a plant sociological vegetation survey was carried out to make a classification of correlation vegetation communities, a cluster analysis and an inorganic component analysis on the soil and plant body. Regarding the vegetation of the coastal dunes, plant communities were classified into 31 communities by correlation dominant species, and as a result of a cluster analysis on the vegetation communities, they were classified into five vegetation types such as Calystegia soldanella community, Rosa rugosa community, Imperata cylindrica community, Vitex tend community and Elymus mollis community. The soil pH was highest in Seocheon area ($7.54{\pm}1.18$) while lowest in Buan area ($6.29{\pm}2.15$), and regarding inorganic components, the nitrogen content was highest in Robinia while lowest in Imperata cylindrica. The soil PH of vegetation I was highest (8.23) among the five vegetation types, and the organic matter was lowest (71.58). As a result of CCA ordination analysis to examine the correlation among environmental factors, Calystegia soldanella community, Rosa rugosa community and Imperata cylindrica community among the five vegetation types were distributed while they were not affected by soil environmental elements, but Vitex tend community and Elymus mollis community were distributed mainly at the places with high $K^+$ content in the soil.

• 한국해양학회지
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• v.30 no.5
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• pp.480-492
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• 1995

Petrographic investigation has been carried out to determine the composition of the beach sediments and the affecting factors which have controlled their compositional variations from Hyupjae, Aeweol, Iho, Samyang, Hamdeok, Sehwa, Pyoseon, Jungmun, and Hwasun areas along the coast of the Cheju Island. Average mean sizes of the beach sediments are Hyupjae 2.2ø, Aeweol 0.8ø, Iho 1.4ø, Samyang 2.4ø, Hamdeok 1.6ø, Sehwa 1.5ø, Pyoseon 2.1ø, Jungmun 0.4ø, and Hwasun 0.9ø, thus, aries from 0.4 to 2.4ø. The beach sediments from Pyoseon and Hwasun areas are poorly sorted, those from Aeweol and Jungmun areas are moderately sorted and those from the rest of the areas are moderately well sorted. While-colored beach sediments in Hyupjae, Aeweol, Hamdeok, Sehwa, and Pyoseon areas are mostly composed of calcareous shells (more than 85%) such as mollusk, red algae, benthic foraminiferas, etc., whereas volcanic rock fragment is the dominant component of the black-colored beach sediments in Iho, Samyang, and Hwasun areas. Especially, the relatively white-colored beach sediment in Jungmun area, which is on e of the carbonate-dominant areas, shows a higher content of rock fragments than the other carbonate-dominant areas. The beach sediments in Pyoseon area show a high content of carbonate intercalates. Considering the contributions by organisms according to grain size, grains with the size range of 1∼2ø are mostly composed of calcareous red algae fragments, and grains with the size range of 2∼3ø consist of mollusk fragments. It is also notable that bryozoan fragments comprise about 48% of the sediment in Samyang area with the size range of 0∼1ø. The composition of the beach sediments in Cheju Island appears o be controlled by the riverine supply rate of volcanic rock fragments, the lithology of the rocks distributed ear the beaches, the direction of alongshore currents, and the direction of storms, etc.. It is suggested that the beach sediments in Iho and Samyang areas show black color because of the higher supply rate of the volcanic rock fragments from the nearby rivers, whereas those in the rest of the areas show white color due to the relatively lower content of volcanic rock fragments and higher content of carbonate components transported from shallow marine environment. In Hwasun area, the content of volcanic rock fragments is high, and they are directly from the tuffaceous rocks distributed nearby. Also, the volcanic rock fragments in Jungmun area are transported not only from the rivers nearby but also from the nearby tuffs by storm activities. The beach sediment in Pyoseon area contains a high content of carbonate intercalates, which formed in the nearby shallow marine environment through marine cementation. This indicates that active marine cementation occurs in shallow marine environment near Pyoseon area.

• Korean Journal of Remote Sensing
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• v.12 no.2
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• pp.139-154
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• 1996

In order to evaluate the sensor`s look direction bias in the Landsat TM image and to estimate trends of primary geological lineaments, we have attempted to systematically compare lineaments in TM image, relief shadowed DEM's, and actual lineaments of geologic and topographic map through the Hough transform technique. Hough transform is known to be very effective to estimate the trend of geological lineaments, and help us to obtain the true trends of lineaments. It is often necessary to compensate the preferential enhancements of terrain lineaments in a TM image occurred by to look direction bias, and that can be achieved by utilizing an auxiliary data. In this study, we have successfully adopted the relief shadowed DEM in which the illuminating azimuth angle is perpendicular to look direction of a TM image for assessing true trends of geological lineaments. The results also show that the sum of four relief shadowed DEM's directional components can possibly be used as an alternative. In Euiseong-gun area where Sindong Group and Mayans Group are mainly distributed, geological lineaments trending $N5^{\circ}$~$10^{\circ}$W are dominant, while those of $N55^{\circ}$~$65^{\circ}$ W are major trends in Cheongsong-gun area where Hayang Group, Yucheon Group and Bulguksa Granite are distributed. Using relief shadowed DEM as an auxiliary data, we found the $N55^{\circ}$~$65^{\circ}$ W lineaments which are not cleanly observed in TM image over Euiseong-gun area. Compared with the trend of Gumchon and Gaum strike-slip faults, these lineaments are considered to be an extension of the faults. Therefore these strike-slip faults possibly extend up to Sindong Group in the northwest parts in the study area.