• Journal of the Speleological Society of Korea
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• v.34 no.35
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• pp.23-31
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• 1993

환선굴은 이른바 복합형이면서도 토출형의 석회동굴이다. 동굴내 지형의 기복이 다양하고 동굴 내부에 수많은 대소의 폭포와 여울이 걸려 있는 동굴유가 풍부한 동굴이며 동굴의 2차생성물은 이 동굴의 지표면을 이루고 있는 지층이 빈약하므로 2차생성물의 성장이 활발하지 못한 동굴이다. 동굴 천정의 지층 구조로 보아 제 Ⅰ지구에서는 비교적 이차생성물이 발달되고 있으나 그밖의 동굴 내부지역에서는 발달이 미약하다.(중략)

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.517-522
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• 2010

The riffle and pool play an important role for composing river front, but very little information was used for river restoration considering flood control. In this paper extensive field investigation was carried out to estimate hydraulic processes in the pool. Furthermore diurnal stratification model was developed and applied to assess flow change in pool. The physical mechanism of water flow including diurnal processes was well simulated, the results show that diurnal variation of water flow in the pool about 2 m depth is governed by the level of mixing due to density flow. These effort will be useful to guide field data collection work and to understand primary production.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.210-213
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• 1997

This study for development of close-to nature revetment techniques is conducted to rehabilitate disturbed stream ecosystem. For this objective, the experimental reach as on-site dimonstrated research was set up in Hakyoul, the Yangjaech'on from Oct. 1995 to Nov. 1996. Special emphasis on the developing process of the design of revetments was given to geomorphic character of 3 types of low flow channel bank: point bar, attack point and shallow bay. Each revetment was developed with the consideration on revegetation of emergent plants. And designed techniques were applied to the experimental reach, and were evaluated with monitoring for 1 year. As a result of the process, the experiment suggested ecological alternatives to enhance technical feasibility and to replace the conventional river-work.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.340-349
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• 2009

The natural type section of Gap Stream was divided into 7 sites, such as, closed pool, runs, riffle, opened pool, pool, reek-scattered riffle, and Dam-type pool. The ecological characteristics of fish community at each site was examined from April, 2007 to October, 2008. During the survey period, 29 species belonging to 8 families were collected, and Carassius auratus (St. 1), Coreoleuciscus splendidus (St. 3), Acheilognathus lanceolatus (St. 4) and Zacco platypus (St. 2, 5, 6, 7) were characteristic species that represent each habitat. The species of C. auratus preferred physical habitat with sand-bottom pool, moderate depth of 65$\sim$90 cm, and stagnant water. The species of C. splendidus mainly preferred physical habitat with cobbles and pebbles are scattered riffles (St. 3), moderate depth of 65$\sim$90 cm, and flow velocity is 0.14$\sim$0.85 m $sec^{-1}$. It also preferred where concentration of BOD, COD, TN, TP and SS is low and DO's value is high, because the flow velocity is fast. A. lanceolatus preferred where the depth of water is low (3$\sim$44 cm) like an opened pool (St. 4) and the flow velocity is slow (0.01$\sim$0.02 m $sec^{-1}$). Z. platypus dominated in a variety of habitats such as runs (St. 2), pool (St. 5), rock-scattered riffles (St. 6) and D-type pool (St. 7), and it preferred places where flow is abundant and riverbed structure is diverse. On the other hand, 4 individuals of Iksookimia choii appeared at reek-scattered riffles (St. 6). I. choii appeared in this research lived in where the width of river is 24 m, the depth of water is 3$\sim$35 cm and the flow velocity is 0.01$\sim$0.49 m $sec^{-1}$, and riverbed structure was diversely formed with boulder to sand. Also, water temperature, EC, BOD, COD, TN and TP was low, but concentrations of DO and SS were high comparatively. Therefore, it seems that I. choii can live only in physical and chemical environment with similar conditions.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.723-734
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• 2010

This study aims to analyze the change in vegetation for 10 years after the construction, targeting Suwoncheon, the first domestic ecological stream construction project. As for the section for the study, the section from Gyeonggi bridge to Youngyeon bridge, the first restoration project section, was targeted. The research districts consisted of 3 districts depending on topographical structure. Investigation check cosisted of cross-sectional topographical structure, vegetation status and the structure of herbaceous plant community. As for the cross-sectional topographical structure of the stream, the width of entire stream was 26.5~28.0m and water channel is 10~20m. The area for hydrophilic space was securing spacious riverside. Upper stream of reservoir beam was shallow and slow in reservoir area above weir. Lower stream of reservoir beam, the width of water channel was narrow and ripples were formed. Among species, 9 plants were planted and 6 species plants including Salix gracilistyla, Phragmites communis and Zoysia japonica were planted at the time of construction. In the water side, there were 2 species, such as Zoysia japonica and Trifolium repens, etc, still remained after seeding at the time of constrcution. The planted plants which were observed through this investigation, were 2 species such as Festuca arundinacea and Dactylis glomerata. Apart from the planted plants, arid climate herbaceous plant such as Setaria viridis and Artemisia princeps var. orientalis formed power and the naturalized species variously emerged in 15 species. For revetment, natural stone stacking method was condicted and Salix gracilistyla, Aceriphyllum rossii, etc were planted. But all the planted plants disappeared and now it was covered with Equisetum arvense and Humulus japonicus. It was because that the base for growth and development of the plants was not constructed at the time of restoration in a way of attaching natural stones onto the concrete base. In the water channel, various wetland species including Typha orientalis, Acorus calamus var. angustatus and Phragmites communis, etc, were planted but only Salix gracilistyla, Phragmites communis and Zizania latifolia remained. As for species of the autochthons, Persicaria thunbergii was dominant. In the lower stream of reservoir beam, Humulus japonicus formed forces. In the hydrophilic space, it was necessary to direct the landscape of in-stream vegetation in cosideration of users. For this, planting Miscanthus sacchariflorus in a community was proposed. In the upper stream of reservoir beam, suplementary screen seeding was necessary so that Zizania latifolia, Typha orientalis and Phragmites communis can fit the depth of water. In the Lower stream of reservoir beam, it was necessary to constantly manage Humulus japonicus so that the wetland autochthons species, such as Phragmites communis and Persicaria thunbergii can establish power more stably.

• Journal of Korea Water Resources Association
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• v.38 no.3 s.152
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• pp.235-244
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• 2005

This study was carried out in Osan river to quantitatively investigate behavior of attacked microbial community (AMC) for enhancing self-purification process of river. We gained the results such as follows throughout long-term monitoring at in-situ river. The biomass of AMC had higher in the riffle than the almost stagnant pool and they were more developed in the riffle with high current velocity (HCV). Although the fast flowing current affects negatively to growth of the AMC during the early phase when the community gets attached to the benthic substrate, it was observed that it affected positively to their growth during the intermediate and later phase after the community is adapted to the substrate. When turbulence due to external pressure (storm or discharge of dam and reservoir) occurs, the degree of separation depends upon the flowing strength and the type of the external pressure. Since the community is not all separated, recovery is rather fast. Therefore, this study found that the degree of reduction of the pollutant by self-purification of the stream is depended upon the riverbed shape and the AMC contributes to self-purification positively or negatively in river. Therefore, the riverbed shape must be constructed in accordance with the characteristics of water quality in stream. Furthermore, the technique of installing the water channel structure appropriate for each section must be developed to maximize self-purification ability.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.366-373
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• 2020

This study investigated habitat diversity changes by conducting weir operations at the Sejongbo site in the Geum River basin. High-resolution aerial photographs taken before and after the weir-opening operation were used for habitat analyses. We classified water and bar areas into 17 types, such as lotic habitats, including riffles, runs, and glides, and lentic habitats, including reservoirs, pools, bar-head backwaters, and bar ponds. Then, we estimated each habitat area quantitatively, calculated a habitat diversity index, and established a habitat diversity map. Our results indicated that after the weir-opening operation, lotic habitats and new types of shallow lentic habitats increased in the water area. In addition, for the bar area, bare lands without cultivation increased distinctively. Finally, we observed that the habitat diversity index drastically increased after the weir-opening operation, which could provide a relatively simple channel of diverse habitats.

• 보일러설비
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• no.9 s.152
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• pp.100-107
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• 2006

박람회 전문기업 동아전람은 바르고 유익한 건축정보를 제공하고 업체 마케팅 장소 제공 및 관련산업의 활성화를 위해 '2006 제16회 mbc건축박람회'를 지난 8월 17일부터 212일까지 5일간 지하철 3호선 학여울 역의 서울무역전시장에서 개최했다. 박람회에는 200여 업체 참가하여 총 2,000여 아이템을 전시됐다. '동아전람 사이버 건축박람회'와 병행해서 동시에 개최된 이번 전시회는 건축자재전, 인테리어전, 건축Renovation전, 전원주택전, 조명산업전, 건축공구전, DIY산업전, 가구전, 부동산 분양 및 펜션 정보전으로 펼쳐졌다.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.194-197
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• 2011

스마트 기기의 급격한 발전, 의료분야와 IT 기술의 융합, 소비자들의 높아지는 요구로 인해 8 비트 이하 마이크로 컨트롤러의 활용도가 높아질 전망이다. 이 논문에서는 EISC구조의 8 비트 마이크로 컨트롤러인 NH800의 ISA를 소개하고, 마이크로 컨트롤러를 위한 오픈소스 컴파일러인 SDCC에서 사용하는 ASxxxx Tool을 이용한 NH800 어셈블러 포팅을 제시한다.

• Korean Journal of Ichthyology
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• v.11 no.1
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• pp.1-11
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• 1999

The five species of the genus Microphysogobio in Korea are reviewed with the keys to species and their illustrations: M. longidorsalis, M. jeoni sp. nov., M. koreeneis, M. yaluensis, and M. rapidus. Microphysogobio tungtingensis uchidai was treated as a junior synonym of M. yaluensis based on having the distinct papillae of upper lip and the color pattern on body sides by the examination of the type specimens. Microphysogobio jeoni is described as a new species from the specimens collected in the Naktong River, Han River and Keum River, Korea. it is well distinguished from the related species by the slender body, undeveloped papillae of upper lip and unspotted fins. Microphysogobio yaluensis was showed the clinal variations in the number of lateral line scales and vertebrae among the populations in the western drainages of Korea. It is remarked biogeographically that the five species of Microphysogobio are all endemics to Korea with the restricted ranges.