• Journal of Korea Water Resources Association
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• v.43 no.11
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• pp.985-994
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• 2010

Typoon Maemi landed on the southern coast of Korean Peninsula at 21:00, September 12, 2003 with a central pressure of 950 hPa. A three dimensional (3D) inundation model was established to calculate the storm surge and flooded area due to Typoon Maemi. A field survey of storm surge traces in Masan City was carried out to evaluate the inundation water depth. Hydromet-Rankin Vortex model was used to calculate the atmospheric pressure and the surface wind fields. The inundation area, storm surge and typoon-induced current were calculated using the 3D model. The peak of computed storm surge in Masan Port using the 3D model was 238 cm, and the observed peak was 230 cm. The simulated storm surge and the inundation area showed good agreement with field survey data. The comparison of the 3D and the two dimensional (2D) models of storm surge was carried out, and the 3D model was more accurate. The computed typoon-induced currents in the surface layer of Masan Bay went into the inner bay with 30~60 cm/s, while the currents in the bottom layer flowed out with 20~40 cm/s.

• East Asian mathematical journal
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• v.26 no.2
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• pp.141-150
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• 2010

In this study, we study on the length of bisector of angle by the method using the area, the method using the vector and the method using the similarity, also the length of trisector of angle by the method using the sine law, the method using the area and the method using the second law of cosine in triangle, respectively. And we study on the length of trisector of angle with the length of bisector in angle. This study is expected to use the learning materials for the interesting construction and the problem solving using trigonometric functions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.2
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• pp.61-71
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• 2014

A river fishway is a hydraulic structure enabling fish to overcome stream obstructions such as dams and weirs. The main aim of this paper is to investigate the collectibility of upstream-migrating fishes and hydraulic problems in pool-and-weir type fishway which has been established for upstream-migration at Namgang weir in the downstream of Namgang dam, and to grope for improvement measures which pool-and-weir type fishway can be switched to pool-and-partial weir type fishway through hydraulic field experiment. Exsisting fishway had problems which upstream-migrating fishes can not take a rest due to the seiche and vortex phenomena in pools and migrate to upstream because of height difference in entrance pool. In order to prevent hydraulically the seiche and vortex phenomena and establish rest area for fishes in each pool, we carried out hydraulic field experiments. In the fishway, it was to improve pool-and-weir into pool-and-partil weir, to decrease the height difference in entrance pool, and to reduce oriffice velocity of each pool. Also, we investigated fishes collectibility of after improving fishway for 6 days in September 2013. To resolve chronic problems(seiche-vortex phenomena and rest area for fishes), as weirs were remodeled into partial weir only which central part of weirs was part of non-overflow weir, we confirmed results that pool-and-weir type fishway could be switched to efficient pool-and-partial weir type fishway with relatively simple construction and low cost. Type-B which has the closed oriffices and the parts of non-overflow has the ideal conditions, but this conditions are limited to fishway of Namgang weir used in this study. Representative Ice-habor type fishway is pool-and-partial weir type fishway which has together parts of overflow and oriffices, and has excellent ability of upstream-migration. To switch from pool-and-weir type fishway to pool-and-partial weir type fishway, the size of oriffice has to be regulated by the discharge of fishway and the dimension on parts of non-overflow and overflow in weirs. Entrance pool is important facility which upstream-migrating fishes have to not only be collect but also charge with energy. In this study, entrance-pool is temporary and roughly-built, but fishes gather together more than the case of no entrance-pool. In the case of fishway which was protruded to downstream, as entrance of fishway turns toward or parallels to weir, the collectibility of fishway was excellent by attraction water.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.65-71
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• 2015

Red Tide phenomenon which happens in the southern coast of Korea gives massive damage to the fishermen who run fish farms and thereby a lot of efforts to prevent damage are made from various angles. In particular, red tide monitoring with satellite imagery can make it possible to obtain the occurrence data of red tide throughout the whole areas of the sea, which helps provide important information for establishing the preventive plans of disasters. In this regard, this study selected the South Sea of Gyeongnam Province with a view to suggesting the monitoring results with regard to the spread and reduction of the Red Tide in the middle of the day by using the GOCI Images of COMS. With this intention, it selected the region in the South Sea of Gyeongnam Province. The study results of analysis on the GOCI image data for the years of 2013(Aug. 12) and 2014 (Sep. 11) are as follows: the pattern of the Red Tide in the region of the South Sea occurred in the southern sea area of Geoje-do in the morning. It gradually spread and showed a gradual decline after reaching the top at 1 PM. In addition, in terms of the tide movement in the middle of the day, Red Tide began in the southern sea area and moved to the west, and moved to the east again at noon. It is judged that additional study on many factors such as the characteristics of the future Red-tide organisms, tidal currents, amount of sunshine, and water temperature is needed, but it is estimated that Red Tide movement monitoring with GOCI images would provide very crucial information for predicting the spread and movement of the Red Tide to protect and manage the Red Tide disasters.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.113-119
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• 2010

This study examined figurative characters of rice terraces, and is intended to seek figurative possibility of a natural scene by selecting Gyeongnam Area Namhae Gacheon rice terraces, Sancheong Imcheon rice terraces and Hamyang Macheon rice terraces through an analysis of the target land. As a theoretical background, studies of a natural scene and figuration-related literature were looked into, and for figuring a natural scene on the basis of the results, the character of the topography of rice terraces was divided into 9 items as follows by generalizing the inspiration obtained from the natural scenic character and spatial character of rice terraces represented from the topography: (1) Inclination showing the degree of the slope of rice terraces, (2) The bending showed by unevenness of the edge line of rice terraces, (3) The degree of parallelism of the up-and-down edge line, (4) The size of the width of the section of each rice terrace, (5) The area of the total rice terraces, (6) Step gap that indicates the difference of high and low of the up-and-down small rice terraces, (7) Figuration as an image represented by the external form of the total rice terraces, (8) Naturalness and artificiality kept by the total scene, (9) Softness of cornerstones or soil that forms small rice terraces, an atmosphere produced by the total scenes, etc. The results of analysis made through GIS, with rice terraces of Gyeongnam Namhae, Sancheong and Hamyang Area as the target land, are as follows. First, the steeper the inclination is, the higher the step difference of cornerstones becomes, and the steeper the inclination, the narrower the area and width become, so that it could be known that, in rice terraces, inclination is proportional to step difference and the area is inversely proportional to the width. Second, it is considered that line showed in rice terraces, area elements and reiteration, repeated changes, and changes in the scene affected by the surrounding environment including those according to season can be converted into a variety of images according to an individual disposition. Third, it was decided that it is possible to figure repetitive composition and directivity, motility, order and change, etc. into a common type drawn from each target land. This paper, as a study of basic materials for expressing figuration in an environment field, investigated and analyzed the surrounding environment of the target land, and is significant in that it attempted the possibility of being able to generalize the environmental beauty of the target land as one figurative element. More precise studies are expected to be made later.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.51-60
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• 2016

This study was conducted to examine litter fall, litter decomposition, and a short-term nutrient (C, N, P, K, Ca, and Mg) status for one year at various levels of basal area (21.4, 27.0, 30.8, 37.0, 42.1, and 46.7 m² ha^-1) in approximately 40-yearold red pine (Pinus densiflora S. et Z.) stands in the Hwangmaesan mountain forest in Korea. Monthly fluxes of litter fall components such as needles, broad leaves, branches, bark and total litter fall followed a similar pattern at various levels of basal area. Mean annual needle, bark and total litter fall fluxes were positively correlated with increased basal area (p<0.05), but the woody litter such as branches and cones was not correlated with basal area. Carbon and K concentrations of needle litter were negatively correlated with increased basal area, while nutrient (C, N, P, K, Ca, and Mg) fluxes were positively correlated with the basal area treatments. Remaining mass, N and P concentration and remaining N and P stocks in decomposing needle litter were not affected by the basal area. However, the concentration and stocks remaining of K, Ca, and Mg from decomposing litter were positively correlated with increased basal area during the initial three months of decomposition. The results indicate that basal area has an impact on nutrient cycles through change in litter fall and litter decomposition processes; thus, the dynamics of nutrient cycles based on a stand scale could differ considerably with different levels of basal area in red pine stands.

• Korean Journal of Medicinal Crop Science
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• v.13 no.1
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• pp.21-29
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• 2005

This study was done to obtain their morphological traits to analyse genetic diversity and intraspecific relationship of 47 Polygonatum species collected from Gyeongnam province. Plant height was the highest in P. thunbergii but the shortest in P. involucratum. Growth habit and its colors were classified to 3 groups, respectively. Leaf shapes were sorted to 5 groups including lanceolate with petiole or none, petiole colors were done to 3 groups including a species having dark green leaves of purple colored margin. Flower shapes were divided as 3 groups of urceolate, tubular and gourd shapes, and its colors were white, greenish white and light green, especially light green in a species with gourd shape. Filament shapes were two types of flatness and cylinder. Peduncle color and bract attached below it showed 4 types, respectively. Fruit shapes were sorted to 3 groups. In 100-fruit weights P. ordoratum var. pluriflorum showed the greatest but P. involucratum did the least. Two species were completely resistant to leaf brightness although 7 species showed less than 7 % infection rates. Rhizome yields ranged from 4.4 g to 94.8 g per plant, showing their significant variation. In correlation analysis between 9 major characters, rhizome yield per plant was positively correlated with plant height, stalk diameter, leaf number, leaf length and width, and rhizome diameter but leaf brightness was negatively done with plant height, stalk diameter, leaf number and length, 100-seed weight, rhizome yield per plan and rhizome diameter.

• Journal of Korea Water Resources Association
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• v.49 no.10
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• pp.809-821
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• 2016

The study area is local river of 671 (total length 3,741 km) in Gyeongnam prefecture, the results are as follows. Total number of river-crossing structures was investigated as 7,730, and it was found that structures were installed in 2.1 sites per 1 km (river length) on average. Diversion weirs for agriculture were 4006 (51.82%) and drop structures for channel bed maintenance were 3670 (47.48%), but the rest (riverbed road etc.) were 54 (0.70%). The number of high structures (height > 1.0 m) that affect many impact in upstream and downstream was investigated as 3,897 (51%), and the number of low structures (height < 0.5 m) that affect negligibly was 1109 (14%). Fish ladders have been installed on 640 (8%) structures in 153 (23%) rivers. In flood control and environment conservation, river-crossing structures brought about various impact that flood water level is raises and the eco-corridor is intercept. In order to improve these problems, we proposed a few engineering measures that can be realize with respect to river-crossing structures.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.209-218
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• 2018

This study was carried out to investigate the occurrence and distribution of ALS inhibiting herbicide-resistant weeds and to estimate the appeared areas of resistant weeds in the paddy fields of Gyeongnam province of Korea in 2017 and 2018 using a soil assay method. Compared with the 2012 survey, this study showed that the infested ratio of ALS inhibiting herbicide-resistant weeds increased from 1.0% to 66.8% and the infested area increased from 876 ha to 49,008 ha. The infested area of ALS inhibiting herbicide-resistant weeds was estimated in Ulsan-si (8.4%), Hapcheon-gun (8.3%), Haman-gun (7.9%), Goseong-gun (7.9%), Hadong-gun (7.3%), Jinju-si (7.2%), Changnyeong-gun (7.0%), Gimhae-si (6.4%), Miryang-si (5.5%), Busan-si (4.9%), Uiryeong-gun (4.6%), Namhae-gun (4.3%), Geochang-gun (4.2%), Changwon-si (3.8%), Geoje-si (2.9%), Yangsan-si (1.8%), Sancheong-gun (0.9%) and Tongyeong-si (0.4%), and the herbicide resistant weeds was not occurred in Hamyang-gun. The most dominant ALS inhibiting herbicide-resistant weeds in paddy fields were Monochoria vaginalis, followed by Echinochloa oryzicola, Lindernia dubia, Scirpus juncoides, Ludwigia prostrata, Cyperus difformis, Sagittaria trifolia and Rotala indica. ALS inhibiting herbicide-resistant M. vaginalis, L. dubia, and E. oryzoides occurred throughout Gyeongnam province, and ALS inhibiting herbicide-resistant S. trifolia and R. indica were only found in Gimhae-si. Therefore, these results will be utilized to estimate population dynamics of ALS inhibiting herbicide-resistant weeds and provide proper management practices in the paddy fields of Gyeongnam province.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1117-1123
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• 2017

Objective: This study was conducted to compare growth performance, blood components and carcass traits by two feeding systems (concentrate with roughage separately [CON] vs total mixed ration [TMR]) in Hanwoo steers, and to learn the relationship between blood components during fattening or finishing phases and carcass traits in Hanwoo steers. Methods: Sixty steers aged 8 months were allotted to two feeding systems and fed similar amounts of average dry matter and total digestible nutrient throughout whole experimental period according to each feeding program. Steers were weighed monthly, taken blood at the end of growing, fattening and finishing periods, and slaughtered at 30 month of age. Results: Growing performance was higher (p<0.05) in the CON group compared to the TMR group during fattening and finishing periods. The CON group was lower (p<0.05) in blood aspartic acid transaminase, blood urea nitrogen and retinol levels during growing period, but higher in triglyceride and cholesterol levels during fattening and finishing periods compared to the TMR group. The CON group was greater (p<0.05) in rib-eye area, and lighter (p<0.05) red in meat color compared to the TMR group. In the correlation coefficients between blood components of steers and carcass traits, retinol had a negative (p<0.05) correlation with marbling score and rib-eye area. Leptin had a positive (p<0.05) correlation with back fat thickness. Blood cholesterol and triglyceride were positively (p<0.05) correlated with carcass weight and rib-eye area. Conclusion: Growth performance, carcass ribeye area and meat color showed a more desirable result in the CON compared to the TMR in Hanwoo steers. Assessing the accumulated data of carcass traits with blood components including hormones-particularly retinol, cholesterol, triglyceride, and leptin-during the fattening or finishing phases, it may be possible to find a biomarker for determining beef quality in living animals.