• Title/Summary/Keyword: 선버들

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Space Rover Development and Domestic Technology (우주로버의 개발현황과 국내의 관련기술 현황)

  • Ahn, Seok-Min;Lee, Yung-Gyo;Kim, Sung-Phil;Kim, Tae-Sik;Moon, Sang-Man
    • Current Industrial and Technological Trends in Aerospace
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    • v.6 no.1
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    • pp.27-34
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    • 2008
  • One of the purposes of space exploration is to be able to utilize the unlimited natural resources in the universe. For this purpose, plans for lunar and mars bases have been proposed by leading nations. In order to construct bases and search for resources, it is necessary to employ and develop rovers for surface navigation and exploration. With proper knowledge about Lunar surface, technology for lunar rover development can be established without serious obstacles, since robot technology for rover development has been well prepared in Korea. In this paper, lunar rovers and mars rovers developed and planned by other countries as well as the current status of robot technology in Korea have been analyzed.

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Vegetation structure and environmental factors in Paksil-nup Wetland, Hapcheon (박실늪의 식생 구조와 환경 요인)

  • Kim, Cheol-Soo;Lee, Pal-Hong;Son, Sung-Gon;Oh, Kyung-Hwan
    • Journal of Wetlands Research
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    • v.2 no.1
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    • pp.31-40
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    • 2000
  • The flora, vegetation structure and physico-chemical characteristics of surface sediment were investigated in Paksil-nup wetland of Hapcheon-gun, Gyeongsangnam-do, Korea in 1990~1998. Ranges of the surface sediment characteristics such as pH, conductivity, organic matter, total nitrogen, available phosphorus, exchangeable K, exchangeable Ca, exchangeable Mg, and exchangeable Na were 4.36~4.34, $19.0{\sim}1260.0\;{\mu}mho\;cm^{-1}$, 0.01~6.35%, 0.001~0.14%, 0.01~0.31 mg/l00g, 1.01~13.98 ppm, 16.75~143.80 ppm, 0.93~14.85 ppm and 0.21~3.86 ppm, respectively. Percentages of the particle size such as sand, silt, and clay were 13.0~93.3%, 5.4~71.7%, and 0.5~37.5%, respectively. The flora of the study area was composed of 72 families, 182 genera, 223 species, 36 varieties and 2 form or total 261 kinds, and those were 45 kinds of vascular hydrophytes and 216 kinds of vascular hygrophytes. The life form of vascular hydrophytes was classified as 27 kinds (60%) of emergent plants, 8 kinds (18%) of submerged plants, 6 kinds (13%) of free-floating plants and 4 kinds (9%) of floating-leaved plants, respectively. The importance value of Salix nipponica was highest as 123.78 in the shrub and tree layers, and that of Trapa japonica was highest as 16.69 in the herb layer. The vegetation type was divided into two groups according to the association analysis. The vegetation of the littoral zone was classified into 7 associations according to the cluster analysis based on the coverage data. These results showed significant differences with those of stand ordination by correspondence analysis based on the species composition and by PCA based on the sediment properties. Factors affecting the distribution of the vascular hydrophytes and hygrophytes were the gradient of particle size, altitude, and water depth.

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Growth Characteristics of Salix nipponica (선버들의 생장 특성)

  • Lee, Pal-Hong;Son, Sung-Gon;Kim, Cheol-Soo;Oh, Kyung-hwan
    • Journal of Wetlands Research
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    • v.4 no.2
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    • pp.1-11
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    • 2002
  • The morphology, seed germination, and life history of Salix nipponica were investigated in the wetland of the Nam-River, Jinju, Gyeongsangnam-do, Korea from 2000 to 2001 to provide the basic data necessary for riverine ecosystem restoration through understanding the growth characteristics of Salix nipponica. Salix nipponica had stomata on only lower side and stomata type was paracytic. Salix nipponica produced many small and light seeds. The seed number per mature ament was 1599.4, seed mass of 0.04 mg, and fertilization rate of 66.1%. Seed germination was little affected by light. Germination rate was high and mean germination time was short Under flooding condition, seeds were germinated normally and were viable after as much as 14 days of flooding. But there were no differences under various water depths on germination rates. Tree age was closely correlated with more stem diameter than tree height and there was no difference of growth rate between male and female tree. Growth rate was most rapid for 2 to 3 years after germination, and length growth was almost stopped for more than 11 years even though mass growth was done. Besides even a second-year indivisual was flowered.

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Distribution and Characteristics on Water Level Change and Salix subfragilis Community Formation in Namgang-dam (남강댐의 운영수위 변경에 따른 선버들 군락의 분포현황 및 특성)

  • Jung, Hea Reyn;Kim, Ki Heung;Park, Jae Hyeon;Lee, Suk Bae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.16 no.6
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    • pp.1-15
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    • 2013
  • The present Namgang Dam had been completed in 2000, Salix subfragilis communities began to form in 2003 and their distribution area have been rapidly extended into nine times in 2010. In order to deduce correlation between water level and distribution of Salix subfragilis communities under this background in Namgang-dam reservoir, distribution characteristics and widening direction of Salix subfragilis communities have been analyzed by aerial photographs and water levels has been reviewed, also heights and ages of Salix subfragilis have been surveyed in field. The water levels of Namgang-dam related germination of Salix subfragilis have been analyzed in May and June from 2000 to 2010, mean water level, minimum water level and maximum water level were 37.87m, 36.99m and 38.82m, respectively. The oldest ages were 9-13 years, average diameters of breast height, average heights, average numbers and average crown area were respectively 3.9-8.8cm, 3.8-7.5m, $0.53/m^2$ and $0.98m^2/m^2$ in sites. Therefore, this results showed that the first recruitment of Salix subfragilis was in May 2002 when water levels have been maintained as 38.76-41.31m and the widening of Salix subfragilis communities was in May 2004 and 2005 when mean minimum water levels have been maintained as 38.76-41.31m. Salix subfragilis communities formed climax forest in Namgang-dam shore, this phenomena were different from the succession processes of Salix in rivers appeared landforming by deposition of sediment.

Topographical change of sandbar and vegetation settlement in Jang-Hang wetlands for Han River Estuary Wetlands Restoration (한강 하구 습지복원을 위한 장항습지의 사주 지형변화 및 식생정착)

  • Ahn, Hong-Kyu;Kim, Si-Nae;Chung, Sang-Joon;Lee, Dong-Jun;Lee, Sam-Hee
    • Journal of Wetlands Research
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    • v.14 no.2
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    • pp.277-288
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    • 2012
  • Estuary is unique habitat ground under substantial changes of water quality, river side, bed material, and micro topography. Construction of SinGok underwater weir with excessive dredging for downstream of weir has changed hydraulic conditions of Han River. This study investigates spatial changes of estuary and expansion process of vegetation on sandbar for JangHang estuary in Han River through analysis of physical and ecological characteristics. As a result of investigation, we found that area of sandbar in JangHang estuary is expanded six times compared between 1985 and 2006, and area of Phragmites australis is gradually decreased while area of Salix subfragilis Anderson. is increased. Also the analysis result of soil layer shows that the Jang-Hang wetlands are created by effect from river, and woody plants are settled from middle part of wetlands, then spread to upper and lower part of wetlands.

Diversity and Distribution of Plant Communities on the Ungok Wetland in Gochang (고창 운곡습지의 식물군락 다양성과 분포 특성)

  • Kim, Jong-won;Lee, Seung-eun;Ryu, Tae-bok
    • Korean Journal of Ecology and Environment
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    • v.50 no.3
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    • pp.295-304
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    • 2017
  • The Ramsar protected area in Ungok wetland, which has been designated since 2011, was described by syntaxonomy and synchorology. Phytocoenon was identified and named by a traditional method of the $Z{\ddot{u}}rich$-Montpellier School and Code of Phytosociological Nomenclature. Habitat-based vegetation classification has identified into twelve syntaxa consisting of 88 taxa in seven vegetation types: Juncus effusus var. decipiens-Salix koreensis community, Caricis-Salicetum subfragilis, Galium spurium var. echinospermon-Phragmites japonica community, Phragmitetum australis, Scirpetum fluviatilis, Leersia japonica-Typha angustifolia community, Juncus diastrophanthus-Juncus effusus var. decipiens community, Leersicetum japonicae, Nymphoido indicae-Trapetum japonicae (typicum, marsiletosum quadrifoliae subass. nova hoc loco, variante Euryale ferox), Nelumbo nucifera community, Utricularia tenuicaulis community, Potamogetonetum crispi. Actual vegetation map was made by using topographical map of scale 1 : 5,000. Habitat-based management on the Ungok wetland vegetation was required, in which there are composed of two major areas such as the back-swamp vegetation and the limnetic vegetation zone.

A Study on the operating activation of small dock - focusing on the busan new port (중소형부두의 운영 활성화 방안 연구 - 부산 신항을 중심으로)

  • Ko, Beo-Deul;Lee, Myoun-Soo;Nan, Ki-Chan;Kwak, Kyu-Seok
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.06a
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    • pp.408-409
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    • 2011
  • Transshipment cargo volume in 2010 compared to 1st quarter 2011 increased 8.43 percent of busan port for transshipment of cargo. thus transshipment of cargo is growing among, south east container terminals and Horando area of new port is planing to develop using small dock for the operations in order to enable. therefore, this study is to deduce implications for operating activation about 6 berths of feeder port in pusan new port that is planing to develop with dock that could be docked very large container ships and feeder dock that could be handled transshipment of cargo.

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A Synecological Study of the Riverside Vegetation of the Upper Stream of Nakdong River, Korea1a - I. Forest and Shrub Vegetation - (낙동강 상류의 하천변 식생의 군락생태학적 연구 - I. 삼림 및 관목성 식생 -)

  • Song, Jong-Suk
    • Korean Journal of Environment and Ecology
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    • v.22 no.4
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    • pp.443-452
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    • 2008
  • This study conducted a survey on forest and shrub vegetation in the riverside of the main stream of the Nakdong River on the southeastern part of Korea based on the method of ZM school of phytosociology. As a result, this study identified the vegetation units as ten associations and communities belonging to three classes, and four communities unclear to the upper units. The identified vegetation units were as follows: A-1 Acero-Fagetea class group, Fraxino-Ulmetaria, undecided alliance: 1) Fraxinus mandshurica community; Zelkovetalia(prov.), Zelkovion(prov.): 2) Zelkova serrata community, A-2 Salicetea sachalinensis, Salicetalia koreensis, Salicion koreensis: 3) Salicetum koreensio-chaenomeloides, 4) Salicetum koreensis, 5) Hemipteletum davidii, 6) Salicetum gracilistylae, 7) Salicetum graciliglandis, 8) Salicetum subfragilis, A-3 Rosetea multiflorae, Dioscoreo-Puerarietalia lobatae, Actinidio-Vition coignetiae: 9) Stephanandra incisa community, 10) Lycium chinense community, A-4 unclear upper units: 11) Clerodendron trichotomum community, 12) Ailanthus altissima community, 13) Robinia pseudo-acacia community. 14) Amorpha fruticosa community. The community units identified by the study corresponded with the result of cluster analysis quite nicely while the result of PCA analysis in multivariate analyses showed less correspondence with cluster analysis result, but it was interpreted as a degree of aggregation according to anthropogenic influence. The vegetation unit of forests and shrubs, unlike the herbal community in highly common with those of Japan, included five vegetation units unique to Korea at a collective level. On the basis of the above synecological study, this research discussed the relation between each community and environment, and natural environment, etc.

Investigation of Vascular Plants in the Eco-Arboretum Site, Mt. Gumwon (금원산 생태수목원 조성 부지의 관속식물상 연구)

  • Oh, Hyun-Kyung;Shin, Hyun-Tak;Beon, Mu-Sup
    • Korean Journal of Plant Resources
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    • v.21 no.2
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    • pp.117-127
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    • 2008
  • The vascular plants in the Eco-Arboretum site, Mt. Gumwon appeared to be 369 taxa; 84 families, 217 genera, 319 species, 43 varieties and 7 forms. Based on the list of the rare plants, 2 taxa existed in the studied areas; Abies koreana (Preservation priority order; No. 73), Paeonia obovata (No. 97) and based on the list of Korean endemic plants, 12 families, 14 genera, 11 species, 3 varieties, 1 hybrid, 15 taxa existed; Cephalotaxus koreana, Abies koreana (Planted species), Carex okamotoi, Salix hallaisanensis, Salix purpurea var. japonica, Clematis trichotoma, Thalictrum actaefolium, Lespedeza ${\times}$ tomentella, Vicia nipponica, Stewartia koreana, Hypericum attenuatum var. confertissimum, Paulownia coreana (Planted species), Weigela subsessilis, Aster koraiensis (Planted species). Specific plant species by floral region were total 38 taxa; Paeonia obovata in class V , 13 taxa (Lilium leichtlinii var. tigrinum, Betula costata, Betula davurica, Ulmus davidiana, Spiraea frutschiana, Prunus maackii, Syringa reticulata var. mandshurica, Cynanchum inamoenum, Lonicera subhispida, Cacalia firma, etc.) in class III , 5 taxa (Heloniopsis orientalis, Chrysosplenium pilosum, Acer triflorm, Viola tokubuchiana var. takedana, Teucrium veronicoides, etc.) in Class II . 19 taxa (Dryopteris erythrosora, Arisaema ringens, Veratrum versicolor, Polygonatum inflatum, Salix glandulosa, Betula schmidtii, Alnus hirsuta, Quercus variabilis, Aconitum japuense, Dicentra spectabilis, Chrysosplenium flagelliferum, Impatiens noli-tangere, Ilex macropoda, Tilia amurensis, Fraxinus mandshurica, Trigonotis icumae, etc.)in class I . The naturalized plants in this site were 5 families, 13 genera, 15 taxa (Rumex acetocella, Rumex obtusifolius, Trifolium repens, Oenothera odorata, Erigeron annuus, Erigeron philadelphicus, Bidens frondosa, Taraxacum officinale, etc.) and naturalization rate was 4.1% of all 369 taxa vascular plants.

The Flora of Protected Area for Forest Genetic Resource Conservation in the Mt. Cheongok (청옥산 산림유전자원보호구역의 관속식물상)

  • Byun, Jun-Gi;Shin, Jae-Kwon;Kim, Ju-Yeong;Choi, Seung-ho;Kim, Dong-Kap
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.46-46
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    • 2018
  • 본 연구는 봉화군 청옥산 산림유전자원보호구역에 분포하는 관속식물을 파악하고자 수행하였다. 청옥산 보호구역은 산림청에서 '희귀식물자생지' 유형으로 지정하여 관리하고 있으며, 면적은 약 2,051ha에 달하며 주로 신갈나무군락과 소나무군락이 우점하고있다. 현지조사는 2017년 3월부터 10월까지 계절별로 수행하였다. 조사결과, 보호구역내 관속식물은 86과 258속 390종 4아종 54변종 6품종으로 총 454분류군의 분포가 확인되었다. 이 중 한국특산식물은 가야물봉선, 처녀치마, 할미밀망, 키버들 등 11분류군이며, 산림청 지정 희귀식물은 취약종(VU)에 주목, 백작약, 꼬리진달래 3분류군, 약관심종(LC)에 등칡, 도깨비부채, 정향나무, 말나리, 나도개감채 등 14분류군이다. 식물구계학적 특정식물로는 IV등급인 회리바람꽃, 가지괭이눈, 산겨릅나무, 귀박쥐나물 등 10분류군, III등급인 애기감둥사초, 중나리, 토현삼, 선갈퀴, 금강제비꽃, 노랑갈퀴, 분비나무 등 23분류군, II등급 32분류군, I등급 30분류군이 확인되었다. 외래식물은 오리새, 털별꽃아재비, 왕포아풀, 주걱개망초, 지느러미엉겅퀴, 족제비싸리 등 18분류군이 임도 주변에서 확인되었다. 조사된 관속식물을 용도별로 구분하면 식용식물 181분류군, 섬유용식물 6분류군, 약용식물 143분류군, 관상용식물 52분류군, 사료용식물 172분류군, 염료용식물 9분류군, 목재용식물 22분류군으로 분석되었다.

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