• Korean Journal of Remote Sensing
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• v.5 no.1
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• pp.13-27
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• 1989

In recent years satellite data have been increasingly used for the analysis of floodprone areas. This study was carried out to demonstrate the usefulness of repetitive satellite imagery in monitoring flood levels of the Pyungchang watershed. Runoff characteristics parameters were analyzed by Soil Conservation Service(SCS) Runoff Curve Number(RCN) based on Landsat imagery and Digital Terrain Model data. The RCN average within the watershed was calculated from RCN estimates for all the pixels(picture elements) and adjusted by antecedent precipitation conditions. The direct runoff hydrograph was derived from the unit hydrograph using SCS dimensionless unit hydrograph and effective rainfalls estimated by the SCS method. In comparsion of the direct runoff hydrograph with the measured rating curve their peak times differ by one hour and peak discharges differ by 5.9 percents of the discharge from each other. It was shown that repetitive satellite image could be very useful in timely estimating watershed runoffs and evaluating ever-changing surface conditions of a river basin.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.157-161
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• 2011

Although many researches have been carried out concerning the watershed division in natural areas, it has not been researched for the urban watershed division. If the boundary between two urban areas is indistinct because no natural distinction or no administrative division is between the areas, the boundary between the urban areas that have the different outlets (multi-outlet urban watershed) is determined by only designer of sewer system. The suggested urban watershed division model (UWDM) determines the watershed boundary to reduce simultaneously the peak outflows at the outlets of each watershed. Then, the UWDM determines the sewer network to reduce the peak outflow at outlet by determining the pipe connecting directions between the manholes that have the multi-possible pipe connecting directions. In the UWDM, because the modification of the sewer network changes the superposition effect of the runoff hydrographs in sewer pipes, the optimal sewer layout can reduce the peak outflow at outlet, as much as the superposition effects of the hydrographs are reduced. Therefore, the UWDM can optimize the watershed distinction in multi-outlet urban watershed by determining the connecting directions of the boundary-manholes using the genetic algorithm. The suggested model was applied to a multi-outlet urban watershed of 50.3ha, Seoul, Korea, and the watershed division of this model, the peak outflows at two outlets were decreased by approximately 15% for the design rainfall.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.72-87
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• 2009

This research is insect diversity analysis on the basis of survey results and bibliographies of Hongdo Island, Mts. Seoraksan, Hallasan, Daeamsan & Daeusan, Hyangnobong peak & Geonbongsan nature reserves and Dokdo Protected Natural Area among 10 designated nature reserves. The Mt. Hallasan nature reserve has 1,867 species in 22 orders and shows the highest species diversity. The species diversities of Mt. Seoraksan, Mt. Hyangnobong peak & Geonbongsan, Hongdo Island, Mt. Daeamsan & Daeusan, and Dokdo Protected Natural Area reveal 1,604 species in 19 orders, 704 species in 18 orders, 474 species in 19 orders, 468 species in 16 orders, and 114 species in 11 orders, respectively, in descending order. The order Lepidoptera shows as dominant taxa in Hongdo, Seoraksan, Hallasan, Hyangnobong peak & Geonbongsan, whereas the order Coleoptera as subdominant taxa in these areas. On the other hand, in Mt. Daeamsan & Daeusan, and Dokdo Protected Natural Area, the order Coleoptera appears as dominant taxa whereas the order Lepidoptera as subdominant taxa. The order Ephemeroptera has been shown the highest species diversity in Seoraksan which is reported to 25 species, Odonata in Hallasan to 28, Dermaptera in Seoraksan to 9, Orthoptera in Hallasan to 51, Hemiptera in Hallasan to 175, Homoptera in Seoraksan to 126, Hymenoptera in Hallasan to 183, and Diptera in Hallasan to 206. The species diversity is generally poor in Daeamsan & Daeusan, Hyangnobong peak & Geonbongsan, and Dokdo Protected Natural Area. Maybe this result is caused by the lack of various academic surveys compared to the other areas. It is needed to study systematic academic investigation on insect in the nature reserve areas in Korea, and to plan appropriate management and conservation on natural environment considering biodiversity of each nature reserve area.

• Journal of the Korean earth science society
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• v.25 no.6
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• pp.474-483
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• 2004

This paper analyzed the characteristics of daily ozone variations over Kangreung and Wonju. It was found that the diurnal cycle of ozone over Wonju has a primary ozone peak in the afternoon and a minimum around sunrise, which is a typical diurnal ozone cycle observable in the urban area. However, the cycle over Kangreung shows a primary peak in the afternoon and secondary peak around 3 a.m. The amounts of ozone in the secondary peak is occasionally higher than that in the primary peak. This nocturnal ozone peak is frequently observed year-round, and the highest frequency and extent are observed in spring. The possible cause of this nocturnal ozone increase was investigated using meteorological parameters and the HYSPLIT trajectory model. It was found that the nocturnal ozone peak is highly correlated with strong wind speed, which has led to positive temperature anomaly. The trajectory model revealed that when the secondary peak occurred, the air was originated from the west and a sinking motion subsequently followed. These findings suggested that when the westerly wind is strongest in spring, the polluted airs from urban areas are transported to the upper boundary layer over Kangreung area. In the case of strong wind during the night, nocturnal ozone peaks were produced by active vertical mixing between lower boundary and upper boundary layers.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.690-695
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• 1994

The perilla seed and the germinated perilla seed $(25{\sim}28^{\circ}C$, $2{\sim}3\;days)$ were extracted by n-hexane, and from the extracted oil the antioxidative components were separated, and then the effect of the change in the contents of antioxidative components by germination on the oxidative stability of the perilla oil was studied. The perilla oils were solved acetone and methanol, and kept at $-60^{\circ}C$ overnight and separated into the frozen oil fraction and unfrozen solvent soluble fraction. By comparing the antioxidative stability of the frozen oil fraction the antioxidative components in the perilla oil were found to be methanol soluble. The methanol soluble fraction of perilla oil was applied to silica gel column chromatography and the separated fractions were compared in terms of antioxidative activity. The fraction of n-hexane : ethyl acetate (7 : 3, v/v) showing the highest antioxidative activity was further separated by TLC. The components included in the band $(R_f\;0.71)$ showing the highest antioxidative activity was separated by HPLC. Four peaks were observed on the HPLC chromatogram and the peak areas were changed by germination (perilla seed : peak 1; 46.5%, peak 2; 25.6%, peak 3; 22.6%, germinated perilla seed : peak 1; 43.8%, peak 2; 20.6%, peak 3; 29.8%). The comparative change in the contents of these components was considered to be one factor affecting the antioxidative stability of perilla oil by germination.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.4
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• pp.78-88
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• 2003

The land use changes from non-urban areas to urban areas lead to the increased impervious areas, consequently increased direct runoff and higher peak runoff. Urban areas have also been recognized as significant sources of Nonpoint Source (NPS) pollution, while agricultural activities have been known as the primary sources of NPS pollution. Many features of the L-THIA/NPS GIS, L-THIA/NPS WWW system have been enhanced to provide easy-to-use system. The L-THIA model was applied to the Little Eagle Creek (LEC) watershed in Indiana to evaluate the accuracy of the model. The L-THIA/NPS GIS estimated yearly direct runoff values match the direct runoff separated from U.S. Geological Survey stream flow data reasonably. The $R^2$ and Nash-Sutcliffe values are 0.67 and 0.60, respectively. The L-THIA estimated runoff volume and total nitrogen loading for each land use classification in the LEC watershed were computed. The estimated runoff volume and total nitrogen loading in the LEC watershed increased by 180% and 270% for the 20 years. Urbanized areas -"Commercial", "High Density Residential", and "Low Density Residential"- of the LEC watershed made up around 68% of the 1991 total land areas, however contributed more than 92% of average annual runoff and 86% of total nitrogen loading. Therefore, it is essential to consider the impacts of land use change on hydrology and water quality in land use planning of urbanizing watershed.nning of urbanizing watershed.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.249-257
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• 1991

Chronological changes in the occurrence pattern of the striped rice borer(SRB), Chilo suppressalis Walker, were investigated by analyzing the data collected by 33 light traps of the countrywide monitoring units during the period of 1968-1989. And also relation of incidences between larval and adult populations, emergence time and percent emergence of overwintered larvae were observed in relation to the time of different rice transplantations. Spring moths of SRB in 1985-'89 generally emerged earlier than in 1968-'72 : 30 days earlier at Kwangju, 20 -25 days earlier at Sangju and Naju, 10-15 days earlier at Uljin, Jinju, Goyang, Milyang, Kimhae, etc., 5 days earlier at Suweon, Jinchun, Daejeon, Namweon, Haenam, etc. There was no change in the time of spring moth emergance at Weonseong, Chungju, Seosan, Yongju, and Nonsan. Summer moths of SRB in 1985- '89 also emerged earlier than 1968- '72: 20 days earlier at Uljin, 15 days earlier at Chungju, Yeongdug, and Habchun, 5-10 days earlier at the other areas except Yeongju. There was an overall countrywide decrease in the population of the 1st generation of SRB during the last two decades. The population of the 2nd generation also decreased in 19 areas during the same period, but increased in 14 areas including over 3-fold increases in Kwangju, Naju and Daegu, and double increase in Jinju, Milyang and Gongju. The higher larval population density of 1st genration was taken place in the earlier transplanted fields, whereas the population of 2nd generation were higher at mid-season transplanted (May 30), followed by May 15, June 15, and April 30. The peak of larval population appeared generally 15 days after moth peak in 1st generation, and 10 days after moth-peak in 2nd generation. The earlier transplanted fields were the higher percent damage due to 1st off-springs of spring moths, whereas the fields transplanted in mid-season were higher damage due to 2nd off-springs of summer moths. Average body weights of SRB larvae before overwintering were 65.6 mg, 61.2 mg, and 55.5 mg in early, mid-season, and late transplantations, respectively. In field cage experiments, emergence rate of the overwintered larvae ranged from 28.3-39.8%. In other words, body weights of overwintering larvae were heavier in fields by earlier transplantation, and heavier larvae showed higher percentage of adult emergence. The period from overwintered larvae to adult emergence was longer in the fields of the later transplantations; namely, 44, 49, and 51 days for early, mid-season, and late transplantations, respectively.

• The Journal of Korean Physical Therapy
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• v.26 no.4
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• pp.257-261
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• 2014

Purpose: The purpose of this study was to compare plantar foot pressure distribution in adults and elderly according to obstacle height. Methods: Nine healthy adults and nine older adults were recruited and the subjects provided written informed consent consent prior to participation. Both groups walked and crossed obstacles with heights of 0%, 10%, 20%, and 30% of their height. Foot pressure was measured by peak pressure using the Pedar System (Novel Gmbh, Germany) during obstacle walking with barefeet in shoes. Three trails were calculated on eight areas and then averaged for data analysis. Results: A significant difference in great toe, little toes, and lateral metatarsal area was observed between adults and elderly groups, but other areas did not show significant differences. Foot pressure was increased in groups according to obstacle height. Conclusion: These findings showed that change in foot pressure distribution is more lateral in elderly in order to maintain postural control during obstacle crossing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2494-2504
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• 1996

This paper describes about the spread specturm radio wave propagation characteristics in urban microcells. The experiments are carried out with respect to the mean excess delay, the RMS delay spread, and the received maximum peak power in the two kinds of geogrphical areas, LOS area and N-LOS area, especially whose variations are observed while varying the transmission distance and tilting the transmitting antenna. The typical results obtained in pariticular urban sites in Seoul are 300-600 nsec of mean excess delay and about 75 nsec of averaged RMS delay spread for LOS area, and 270-280 nsec of mean excess delay and about 100 nsec for N-LOS area. With the transmitting antenna gilted, obsered in the experiments are increase in RMS delay spread as expected, but increase of the received power at N-LOS areas in particular.

• Korean Journal of Child Studies
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• v.27 no.3
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• pp.189-205
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• 2006

Gender role flexibility in social and non-social situations across 4 areas of gender-role concepts(appearance, activities, occupations, and personality traits) were studied in 74 1st, 3rd, and 5th grade children. They were interviewed with 16 pictures depicting cross-gender characteristics. Children showed higher flexibility in social than in non-social situations. In social situations, children justified cross-gender characteristics in all 4 areas of gender-role concept. In non-social situations, children showed (a) highest flexibility in occupations and lowest in appearance, (b) lower flexibility toward male than female target children, (c) peak flexibility at age 8, then remaining the same except for appearance, and (d) higher flexibility in girls than in boys. In social and non-social situations children gave variable justifications for flexibility.