• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.73-83
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• 2016

This study modified and applied the ecological network(Indicator 2) from the City Biodiversity Index(CBI) to be tailored to Korea. It is calculated by utilizing a biotope map and a land cover map. The ecological network of Gyeryong-Si was 13,713,703(33.8%) with the biotope map and 17,686,966(37.9%) with the land cover map. The result of the biotope map was lower than the land cover map. The ecological network of Goyang-Si was 4,961,922(4.9%) with the biotope map and 4,383,207(3.7%) with the land cover map. The result of the land cover map was lower than the biotope map. As a main result of the research, an error was discovered in which, when calculating the ecological network, the types of the military unit facilities were distinguished into a special area on the biotope map and into an urbanization promotion area and a forest area on the land cover map. In the case of a middle-classified, land cover map, the land use in the surroundings of the forest area was not subdivided. An error in the development area expressed as a forest green was discovered. When selecting the natural elements, too, regarding the types of artificially-created rivers, artificial ponds, and artificial grasslands, etc. on a biotope map, the exclusions were necessary. Regarding the natural, bare ground on a land cover map, there was a need to calculate by including the natural elements. It was judged that, in the future, the ecological network in the unit of the entire nation can be analyzed roughly by utilizing a land cover map. It was judged that, in a city having a biotope map, the calculation of the ecological network utilizing a map of the present situation of the urban ecology will be a more accurate diagnosis of the present situation.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.30-36
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• 2017

SS(Suspended Solid) concentration by soil erosion into river at normal and flood season should be measured. However, to present the variation of SS due to various development project such as EIA(Environmental Impact Assessment), River Master Plan, and so on, it is necessary to estimate not measure SS, but there are not exist how to estimate SS. In the present study, therefore, we propose the hydrologic method of estimating SS concentration using the results of particular frequency flood discharge and sediment discharge by RUSLE method. SS consists of silty and clay soil and colloid particle etc. However, in the present study, silty and clay soils of sediment discharge except send set up SS standards. The flow discharge to estimate SS concentration are 1~2 years for normal season, 30~100 years for flood season. Meanwhile, analysis software for probable rainfall uses Fard2006, probable rainfalls under 2-year frequency are estimated using rainfall data and frequency factor of Gumbel distribution. The results of estimating SS concentration using runoff volume by sediment and flow discharges of silty and cray soils as above method show that reliable level of SS concentration is considered in predevelopment of natural condition and under development of barren condition. Especially, SS concentration takes notice that the value of sediment discharge makes a huge difference according to channel slope, it was confirmed that the value obtained by dividing the SS concentration by the channel slope is relatively constant even though the topographical factors are different. Therefore, if the present study will be proceeded for various watersheds, it will be developed as estimation method of SS concentration.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.70-80
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• 2011

Estuarine ecosystem responds sensitively to natural and anthropogenic perturbations. lt is necessary to identify the direction of the change when the perturbation occurs as well as to understand the structure and functioning of estuarine ecosystem for a proper management of the area. In this study, the estuarine habitats were classified into different ecological districts so as to the switch from one district to another district could be related to the environmental change due to the perturbations. Total 16 ecological districts was defined according to the presence of barrage, salinity and vegetation characteristics. The defined ecological districts were applied to small estuaries in Goseong bay, south sea of Korea (Baedun, Guman, Maam, Goseong) to distinguish different regions which might have characteristic bottom topography, inclinations of river bottom, sediment characteristics, salinity structure and area of vegetation. Total 7 out of 16 ecological district was identified in this region; NFB (natural, fresh, bare), NHB (natural, high salinity, bare), NLV (natural, low salinity, vegetated) in natural (without barrage) estuaries and CFB (closed, fresh, bare), CFV( closed, fresh vegetated), CLV (closed, low salinity, vegetated), CHB (closed, high salinity, bare) in closed (with barrage) estuary. A comparison of environmental factors and biota between CHB and CLV demonstrated the effect of barrage on estuarine ecosystem. The height and sediment characteristics of CHB and CLV were similar but the average salinity was lower in CLV than in CHB due to the barrage, which produced favorable condition for the Phragmites australis in CLV. Information regarding the ecological districts in various sizes and location could be useful for predicting the ecosystem change due to natural and anthropogenic perturbations and for preparing management actions.

• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.126-141
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• 2021

Fauna of freshwater fish and community structure were investigated at 13 sites in the Deogyusan National Park, Korea from 2014 to 2018. During the period, a total of 8 families, 21 species, and 8,716 individuals of fishes were collected. The number of fish collected over the past five years from 2014 to 2018, were 17 species and 2,280 individuals, 17 species and 1,579 individuals, 17 species 1,905 individuals, 17 species and 1,384 individuals, and 15 species and 1,568 individuals, respectively. There were 13 Korean endemic species including Iksookimia koreensis and Coreoleuciscus splendidus, etc. Only in Wondangcheon Stream, two endangered species were identified, and Hemibarbus mylodon was collected continuously except in 2015, and Pseudopungtungia nigra was observed every year. And two exotic species such as Oncorhynchus masou masou and Oncorhynchus mykiss occurred in Gucheongdongcheon Stream sites. The dominant species was Rhynchocypris oxycephalus and the sub-dominant species was Zacco koreanus and there was no difference by year. The fish community structure of Deogyusan National Park was varied depending on the sites and the year. Most of the survey sites located upper stream where the river structure is Aa river type showed poor community analysis results. On the other hand, the upper-mid stream sites including the Bb type showed better results. As a result, the Wondangcheon Stream sites had the most diverse and stable community structure. Similarity dendrogram was divided into 4 groups, mainly reflecting the characteristics of the habitat. The flagship species of the Deogyusan National Park, Rhynchocypris kumgangensis, was constantly observed during the investigation period. Compared to the previous survey, the number of species increased from 2004 (12 species) and decreased from 2009 (22 species).

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.106-120
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• 2006

Natural or man-made disaster has been expected to be one of the potential themes that can integrate human geography and physical geography. Typhoons like Rusa and Maemi caused great loss to insurance companies as well as public sectors. We have implemented a natural disaster management system for a private insurance company to produce better estimation of hazards from high wind as well as calculate vulnerability of damage. Climatic gauge sites and addresses of contract's objects were geo-coded and the pressure values along all the typhoon tracks were vectorized into line objects. National GIS topog raphic maps with scale of 1: 5,000 were updated into base maps and digital elevation model with 30 meter space and land cover maps were used for reflecting roughness of land to wind velocity. All the data are converted to grid coverage with $1km{\times}1km$. Vulnerability curve of Munich Re was ad opted, and preprocessor and postprocessor of wind velocity model was implemented. Overlapping the location of contracts on the grid value coverage can show the relative risk, with given scenario. The wind velocities calculated by the model were compared with observed value (average $R^2=0.68$). The calibration of wind speed models was done by dropping two climatic gauge data, which enhanced $R^2$ values. The comparison of calculated loss with actual historical loss of the insurance company showed both underestimation and overestimation. This system enables the company to have quantitative data for optimizing the re-insurance ratio, to have a plan to allocate enterprise resources and to upgrade the international creditability of the company. A flood model, storm surge model and flash flood model are being added, at last, combined disaster vulnerability will be calculated for a total disaster management system.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.1
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• pp.2206-2217
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• 1971

Spillway and discharge channel of reservoirs require the Control of Large volume of water under high pressure. The energies at the downstream end of spillway or discharge channel are tremendous. Therefore, Some means of expending the energy of the high-velocity flow is required to prevent scour of the riverbed, minimize erosion, and prevent undermining structures or dam it self. This may be accomplished by Constructing an energy dissipator at the downstream end of spillway or discharge channel disigned to dissipated the excessive energy and establish safe flow Condition in the outlet channel. There are many types of energy dissipators, stilling basins are the most familar energy dissipator. In the stilling basin, most energies are dissipated by hydraulic jump. stilling basins have some length to cover hydraulic jump length. So stilling basins require much concrete works and high construction cost. Flip bucket type energy dissipators require less construction cost. If the streambed is composed of firm rock and it is certain that the scour will not progress upstream to the extent that the safety of the structure might be endangered, flip backet type energy dissipators are the most recommendable one. Following items are tested and studied with bucket radius, $R=7h_2$,(medium of $4h_2{\geqq}R{\geqq}10h_2$). 1. Allowable upstream channel slop of bucket. 2. Adequate bucket lip angle for good performance of flip bucket. Also followings are reviwed. 1. Scour by jet flow. 2. Negative pressure distribution and air movement below nappe flow. From the test and study, following results were obtained. 1. Upstream channel slope of bucket (S=H/L) should be 0.25<H/L<0.75 for good performance of flip bucket. 2. Adequated lip angle $30^{\circ}{\sim}40^{\circ}$ are more reliable than $20^{\circ}{\sim}30^{\circ}$ for the safety of structures.

• Journal of Korea Water Resources Association
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• v.49 no.11
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• pp.931-939
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• 2016

Bangudae Petroglopys of the national treasure No. 285 located in elevation of 53 m to 57 m have been damaged by repetition of submergence and exposure due to the Sayeon-dam of EL.60 m constructed in down stream. In this study, as a preservation plan of the petroglyphs from the contact with water, the construction of eco-levee was suggested and its effect was investigated in the views of hydraulic engineering. It was designed to be located aside of 80 m from Bangudae Petroglyphs with the length of 440 m in streamwise direction, and it was need to construct a new channel maintaining the original hydraulic capacity and conveyance. Hydraulic characteristics such as water surface elevations and velocities near Bangudae Petroglyphs were measured after the eco-levee was installed in the hydraulic model with the scale of 1:50. It showed that there were not much changes of water surface elevations and velocities between sayeon-dam spillway EL. 60 m (Suggestion 1) and EL. 54 m (Suggestion 2). It was concluded the eco-levee could be made of natural materials like soil, pebble, gravel in terms of allowable velocity and shear stresses. The slope of water surface at Suggestion 2 was steeper, and velocities near Bangudae Petroglyphs were also faster than Suggestion 1. As the vorties occured at the left side in Suggestion 2, more detailed study is required.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.444-449
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• 1995

한국형 표준 원자력발전소의 정지냉각운전시 최대냉각율은 75$^{\circ}$F/hr(41.7$^{\circ}C$/hr)로 기술사양서에 규정되어 있다. 정지냉각운전 냉각율에 가장 큰 영향을 미치는 2가지 중요한 변수는 정지냉각계통 열교환기를 지나는 원자로냉각재 유량과 기기냉각수의 온도다. 이중 열교환기를 지나는 원자로냉각재 유량은 butterfly형 정지냉각계통 유량조절밸브의 개도에 의하여 조절되는데 개도에 따른 throttle 능력이 중요한 인자다. 또 기기냉각수의 온도는 해수온도의 변화에 따라 편차가 발생하므로 유량조절밸브의 개도와 기기냉각수 온도의 상관관계에 따라 냉각능력이 달라진다. 본 논문에서는 현 울진 3&4호기 정지냉각계통 열 교환기 및 조절밸브 둥의 설비를 기준으로 기술사양서 상의 냉각율 75$^{\circ}$F/hr(41.7$^{\circ}C$/hr) 유지가 가능한 최저 기기냉각수의 온도를 찾아보았고, 아울러 기기냉각수의 온도와 조절밸브의 개도 사이의 관계를 조사하였다. 그 결과 현재의 울진 3&4호기 조절밸브를 최저개도로 조절할 때 약 57$^{\circ}$F(13.9$^{\circ}C$)의 기기냉각수가 공급되어도 냉각율 제한치를 넘지 않는 것으로 분석되었다. 한편, 최저조절가능 유량이 약 2000 gpm(7570 l/min)일 경우에는 낮은 기기냉각수가 공급될 경우 최대냉각율을 초과하므로 한 train을 정지시키고 한 train만으로 운전할 것을 고려하여야 할 것으로 보인다. 이 경우 최저 약 56.5$^{\circ}$F(13.6$^{\circ}C$)의 기기냉각수가 공급되어야 한다. 본 논문의 분석결과는 향후 기기설계사양서나 운전지침서 등에 반영되어 실제 발전소 설계 및 운전절차 수립에 기여할 수 있을 것으로 생각된다.공감대의 형성이 요구된다. 질적 측면에서는 공원 녹지의 기능성의 회복이라는 측면과 시대에 부합되는 새로운 기능 및 가치의 부여가 필요하며, 이를 위해서는 공원의 매력, 공원의 시설기능 증진, 녹지의 질의 향상 및 녹지 가치의 증진에 대한 다양한 시책이 요구된다. 구성적 측면에서는 공원녹지의 개별적 존재보다는 공원 녹지를 상호간 유기적인 계통을 확보하여 공원 녹지의 네트워크를 형성하여 도시 속의 산재된 고립된 섬으로서의 공원 녹지가 아닌 시민생활에 늘 가까이 있는 생활 속의 공원녹지로 재편되어야 한다. 이러한 정책의 의제는 양적 측면에서 보전(CONSERVATION)과 창출(CREATION), 질적 측면에서 쇄신(RENOVATION)과 복구(RESTORATION), 그리고 구성적 측면에서 공원 녹지의 연결(CONNECTION)과 시민 참여에 의한 운동(MOVEMENT)이라는 정책 개념의 구현을 통해 가능하다. 이러한 정책 개념과 의제를 가지고 서울시 공원 녹지 정책을 구체화시키기 위해서 푸르름의 새로운 탄생이라는 기치 아래 풍요로운 서울, 사랑 받는 공원, 생활 속의 녹지의 3대 목표, 공원 녹지의 보전, 잠재 공원 녹지의 창출, 공원의 활성화, 녹지의 복구, 경관 보전 및 복구, 공원 녹지의 네트워크, 도시 녹화의 7대 과제를 설정하고 미시설 공원 녹지 집행, 개발 사업시 공원 녹지의 확보, 환경 녹지의 총량 보호 관리, 도시 소공원 개발, 역사 문화 공원 조성, 하천 공간 복원, 공원 시설 기능 개선, 이용 프로그램 개발, 공원 관리 개선, 환경 피해 녹지의 회복, 도시 환경 림 조성, 녹지 기능 증진, 도시 자연 경관 보전, 공원 녹지체계 구성, 공원 녹지 공급 균형, 주변 환경 녹화, 가로 녹화의 17개 시책을 제안하였다. 이러한 정책사업의 원활한 추진을 위해서는 기존의 관주도의 일방적인 공원 녹지 행정이 아닌 시민의 참여를 통한 시민이 함께 하는 정 책 사업의 추진이 요구되며, 특히 민간 부문의

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.157-168
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• 2017

Backswamp is the section of a floodplain where deposits of fine silts and clays settle after a flood. In general, the wetland is composed of diverse ecosystems, and is characterized by ecotone. The purpose of this study was to analyze vegetation naturalness and to assess vegetation value by syntaxonomy and synecology of Useupje backswamp at Yeongsan river. As a result, the vegetation was divided into four physyiognomy types and 14 vegetation units depending on the species composition and habitats. The vegetation units confirmed in the study were as follow: Spirodela polyrhiza community as floating plant; Trapa bispinosa var. inuma community and Trapa bispinosa var. inumai-Nelumbo nucifera community as floating-leaved plant; Paspalum distichum community, Persicaria thunbergii community and Phalaridetum arundinaceae as lentic vegetation in the eulittoral zone; Scirpo fluviarilis-Zizanietum latifoliae and Typha angustata community in the emerged zone; Scirpetum tabernaemontani and Phragmitetum australis in the littoral zone; Carex dimorpholepis-Salix subfragilis community ecotone region of upland. According to the study, the vegetation distribution was highly affected by water level and artificial interference. Moreover, the development of vegetation units showed a significant relationship between species composition and habitats. Although vegetation value of Useupje resulted by vegetation naturalness was identified as the grade [III], the ecological value is expected to upward evaluation because of unique vegetation and geographical location.

• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.155-163
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• 1997

The Mongolian ger is ideally suited to the mongol's steppe climate and the nomadic way of life. This is a multipurpose dwelling which can be easily collapsed, transported to another place and put up again fully preserving its original shape. The pastoral nomadic ger has two key components: the wooden framework and the felt cover. The wooden parts are the walls(khana), the long poles(un), the smoke escape(toono) and its supports(bagana). One wall consists of 10-15 branches of willow tree. each about 1.5m high bound together in a way making it possible to fold it for transportation and then unfold it like an accordion. The unfolded walls are connected to form a circle. The long poles(un) are fastened to the upper part of the walls, with the other end passed through the toono hole, the only sky window and smoke escape through it from the ger. The toono is propped up by two posts, called bagana. All this forms the wooden framework of the ger, which is covered with felt. When the herders fire up their metal stoves, the temperature inside the ger becomes quite comfortable. Because the nomads live in a climate where there is only one growing season in a year, they do not make long migrations to new pastures. Livestock subsist on standing vegetation for eight months of the year. The basic pasture migration strategy is to leave enough standing vegetation at the end of the growing season in September to suffice until the new growth appears the following May. Mongolians use a type of compressed tea leaf that is called "brick" tea in English because it is rock solid and roughly the shape of a brick. And they consume a larger percent(88%) of fat from animal products such as meat, milk, butter, and cheese than any other people in the world. Milk products made from the milk of sheep, yak, and goats are major foods in the nomad's diet, but they are produced mainly in summer when all the animals are lactating. Mongolians made their special nomadic food culture on the steppe.