• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.221-231
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• 2015

This is a continuous study on the dam effects for the spatial extension of flood data. In this study, flood reduction rates of dams and their influences on downstream using the spatially extended flood data were implemented. Nam-Han River was selected for measuring the impacts of ChoongJu and HoangSung dams. In the evaluations of flood reduction rate at dams, the larger flood events have the lower flood reduction rates for both dams. At the YeoJoo water level station, the analyses of the relations between flood reduction rates and the sizes of watersheds dams located were performed. the sizes of watersheds having a functional dam have highly influenced on the reduction rates of flood. The average of flood reduction rates was smaller than the area rate. For instances, area rates of HoangSung (0.02) and ChoongJu dams (0.6) are larger than the average flood reduction rates for HoangSung (0.01) and ChoongJu dams (0.51), respectively. However, the water level station follows the dam flood reduction characteristics of dams themselves. The spatial effects of dam flood reductions are analyzed based on the three water level stations (GangChun, YeoJoo, YangPyung). The distance of flood reduction rates lower than 0.1 as average flood reduction rate was the area 7 times of watershed having a dam with 0.02 as a minimum reduction rate.

• Journal of Conservation Science
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• v.33 no.4
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• pp.267-274
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• 2017

The Silleuksa temple in Yeoju city is adjacent to the South Han River and often has high humidity and fog days. In addition, its proximity to forests renders it prone to damage by insects and microorganisms. In order to obtain the basic data necessary for the establishment of a cultural property preservation management plan, the biological distribution of the wooden buildings and the termite distribution in the surrounding forests were monitored for three years. The wood-boring bee, an insect known to inflict damage to heritage structures, was confirmed, and the distribution of insects varied annually and seasonally, presumably due to the location characteristics of the site and the climate change during the year. In the forest behind, termite colonies were identified as a whole and their distribution pattern was different every year. As per the results of the microorganism survey, the species distribution and pollution degree were different at the entrance of the building. Therefore, it needs continuous biological distribution and conservation environment monitoring to mitigate the effects of wood-damaging organisms.were different according to the entrance of the building.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.53-58
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• 2015

Engineers should take great care of characterizing the engineering properties of mudrock, because the uncemented mudrock can be considered as a hard rock in appearance. Therefore, the mudrock samples obtained from the cut slope in Gyeongki-do were tested to evaluate the strength characteristics of uncemented mudrock in this study. The performed tests are index properties, slake durability, and swelling tests for the classification of the mudrock for engineering practice. To evaluate the effect of water on the engineering properties of the uncemented mudrock, resonant column, triaxial compression and direct shear tests with various water contents were performed. With the increasing water contents, stiffness at very small to small strain region and the cohesion value of the strength parameters decrease. Based on the test results, engineers should take great care of evaluating the engineering properties of uncemented mudrock.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.105-112
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• 2011

The objective of this study was to determine the effect of antioxidant enzyme activity and radical scavenging activities of thirteen kinds of natural plant pigments. The analytic method of antioxidant activities were measured by estimating DPPH free radical scavenging and nitrite scavenging ability activity. The free radical scavenging activity by method using stable free radical DPPH was the highest in the red cabbaged pigment. Addition of ethanol extract 1mg/ml from onion peel pigment displayed remarkable effect on nitrite scavenging ability about 91.9%. Antioxidative enzyme activity was evaluated in terms of superoxide dismutase(SOD), catalase(CAT), and ascorbate peroxidase(APX) activity. The bitter melon pigment had the highest SOD activity of 87.3%. The activities of CAT and APX were higher in the mulberry leave pigment compared with other natural plant pigments. In contrast, CAT activity of plant pigment samples were unaffected. These results suggest that natural plant pigment had the potent biological activities such as antioxidant enzyme activities, and that their activities exhibited differently depending on each kind of pigments.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.184-205
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• 2019

Buddhism was introduced to Gyeonggi-Do early on and thus created various types of Buddhist culture there. Since the introduction of Buddhism into Gyeonggi-do, the there has been continuous construction of stone stupas. More stone stupas were built in southern Gyeonggi than in northern Gyeonggi-do. In particular, Anseong, Icheon, Yongin, and Yeoju were centers of construction. Looking at the characteristics of each period, stone stupas remain from the Unified Shilla Period to Joseon, indicating that stone stupas were steadily built during this period. The stone stupa corresponding to the Unified Shilla Period is meaningful in that it shows the northern limit of Shilla Buddhist culture. Since then, the stone stupas of the Goryeo Dynasty were actively constructed in the southern part of Gyeonggi-do in the early Goryeo Dynasty. By the late Goryeo Dynasty, the stupas were built throughout Gyeonggi-do, indicating that the construction of the stupa was active. In the Joseon Dynasty, stone stupas were built in temples near Hanyang and deeply related to the royal family. Stone pagodas were erected mainly on major traffic routes. Stone stupas built in Gyeonggi-do have a variety of artistic and historical significance.

• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.914-929
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• 2007

This study analyzes the accessibility patterns for commuting trips in Seoul Metropolitan Area using National Census Data between 1990 and 2000. the results show that the accessibility increased between 1990 and 1995, while it decreased between 1995 and 2000, due to the raised commuting time. Seoul, Kangju, Yeuju, Yangpyoung, Gapyoung show relatively high accessibility. The GINI parameters tell that the regional balance for commuting accessibility were worsen between 1990 and 1995, compared to that between 1995 and 2000. The accessibility patterns for commuting to Seoul were also analyzed and the result shows that the accessibility reduced between 1995 and 2000. Kwachun, Kwangju, Sungnum are found to have very high accessibility to Seoul, which is close to Soeoul with high percentage of incoming commuting trips. These results indicate that even continuous transport infrastructure supplies were not enough to solve the congestion problems for commuting trips in Seoul Metropolitan Area because of the induced traffic and traffic congestion.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.597-603
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• 2012

To investigate the effects of weir construction on sediment characteristics of river bed, we conducted sediments sampling on the 9 locations near the weir, Kangchun, Yuju and Ipo in Namhan-River. Physical and chemical characteristics of sediments were analyzed by measuring particle size distribution, water content, Ignition loss, COD (Chemical Oxyzen Demand), TOC (Total Organic Carbon), TP (Total Phosphorus), SRP (Soluble Reactive Phosphorus) and TN (Total Nitrogen). Particle classification of all three weir sediments showed sandy loam that was caused by the river bed dredging. Due to the presence of weir, Ignition loss, COD, TOC, TP, SRP and TN showed similar trend such as the concentrations of upward weir had higher than those of downward weir. For the case of SRP concentration and C/N ratio, however, there is not much difference in the sediment characteristics compared to the those of sediments before weir construction. Therefore, It can be predicted that there are little effects of weir construction on sediment characteristics. However, weir construction could influence water quality of the river by controlling the transport and the accumulation of suspended materials from rainfall. Therefore, more intensive monitoring is required to examine the magnitude and patterns of sediment accumulation which could influence overlying water quality.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.182-186
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• 1985

In order to determine the optimum sowing date of peanut in the middle part of Korea, peanut's 100-grain-weight and physico-chemical compositions for peanut cultivars such as runner (Yeoju landrace), semi-spanish (Suweon No. 15) and spanish types (Wasedairu) to different seeding date which planted at interval of ten days from May 5 to July 4, in 1981, was carried out. The 100-grain-weight and crude fat of peanut were increased from May 5 to May 25, but after that decreased. And the 100-grain-weight of peanut was great in order of Wasedairu, Suweon No. 15 and Yeoju landrace. The highest amount of crude fat was seen in peanuts which was sown at May 25 and May 15. Unsaturated fatty acids are composed of $80{\sim}85%$ of oleic and linoleic acid, but saturated fatty acids are constituted of $10{\sim}15%$ of palmitic acid and $1{\sim}5%$ of stearic and arachidic acid. Composition ratio of fatty acid in peanut was changed greatly according to sowing date. According to the late sowing date linoleic and palmitic acid were increased but oleic acid was decreased, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.524-535
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• 2020

This study was conducted to derive implications for the dissemination and expansion of subtropical crops in farms. To this end, the cultivation trends and main producing areas of promising subtropical crops in Korea were analyzed. Analysis results found that the cultivation area of crops, excluding mango, was stagnating or decreasing. The main producing areas of domestic subtropical crops are located on Jeju Island (mango, dragon fruit), in Gyeongsangnam-do (papaya), and in Jeollanam-do (turmeric). Guava and Yeoju could not define the main producing area. For all crops, the percentage of cultivated area in the top 10 regions was high, but only half of the regions maintained the ranking. These results imply that the introduction and abandonment of subtropical crops are frequent. The dissemination and expansion of subtropical crops are justifiable in terms of responding to climate change in the future and creating new income for farms. Therefore, government support policies and agricultural promotion agencies need to be established.