• 국제초고층학회논문집
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• 제6권1호
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• pp.21-31
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• 2017

Jeddah Tower will be the first man-made structure to reach a kilometer in height upon its completion in 2019. From conception, it was clear that an all-concrete superstructure would present many advantages for a building of such unprecedented height and slenderness. An all-concrete structure, however, did present many challenges that needed to be addressed in the system arrangement and through comprehensive analysis and design, among them vertical shortening effects due to the time-dependent creep and shrinkage of concrete. This paper outlines and presents the engineering solutions developed by the authors regarding this complex concrete material phenomenon, while addressing the construction and regional challenges associated with realizing a concrete tower of this unprecedented scale.

• 환경영향평가
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• 제29권4호
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• pp.298-306
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• 2020

본 연구는 새만금호 일대 수달의 서식지적합도 분석과 공간변수(수역, 습지, 농경지, 시가지, 도로 등)와의 상관성이 수달 서식에 미치는 영향을 파악하기 위하여 이루어졌다. 서식지적합성 분석결과, 전체 1097개 격자 중 1등급과 2등급이 380개 격자로 전체 34.6%로 확인되었고 4등급과 5등급이 413개 격자로 전체 37.7%로 비교적 낮은 것으로 확인되었다. 새만금 일대의 공간변수 별 수달 서식흔적과의 거리를 비교분석한 결과, 도로와 시가지는 거리가 멀수록 수달의 흔적이 확인되는 것으로 확인되었고 수역과의 거리는 가까울수록 흔적이 확인되었다. 새만금호 내부 공사로 인한 영향은 있으나 수역과 도로의 이격거리를 보면 시가지와 도로에서 이격거리가 근접한 지역과 가장 먼 지역과의 흔적차이가 2배에서 6배 이상 나타나는 것으로 확인되었다. 이는 수달의 서식지 복원시 위협요인으로 작용하는 도로와 시가지는 최소한 500(m) 이상 이격거리가 필요하다고 판단된다.

• 식물분류학회지
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• 제37권1호
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• pp.61-78
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• 2007

까치수염속 Spicatae절에 포함되는 3종 14집단 34개체의 형태형질을 검토하였고, 이를 토대로 수리 분류학적 연구를 수행하였으며, 본 절의 각 종에 대한 중요형질 및 변이의 한계를 파악하고 종집단간의 유연관계를 고찰하였다. 정량형질보다는 정성형질인 서식지와 엽선 그리고 잎, 탁엽, 줄기 및 포에 존재하는 털의 유무, 줄기의 가지 여부, 화축과 소화경에 존재하는 털의 종류 및 화서의 형태 등이 종 동정에 유용한 식별형질로 밝혀졌다. 또한, 정성형질의 검토에 의하여 큰까치수염과 까치수염이 진퍼리까치수염에 비해 유연관계가 더 밀접한 것으로 밝혀졌고, 이를 근거로 종 검색표를 제시하였다.

• ALGAE
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• 제39권2호
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• pp.59-74
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• 2024

Terrestrial cyanobacteria are extremely diverse. In urban areas, they can be found as black stains on the surface of building walls, stone monuments, or man-made structures. Many of the terrestrial cyanobacteria are still understudied. To expand knowledge of terrestrial cyanobacterial diversity, a polyphasic characterization was performed to identify 12 strains isolated from campus of University of the Ryukyus, Okinawa, Japan. Multigene phylogenetic analyses based on 16S rRNA gene and 16S-23S rRNA internal transcribed spacer (ITS) region showed that the isolated strains formed two independent subclades within Nodosilinea, and were distantly related to all described Nodosilinea species. The 16S-23S rRNA ITS secondary structures showed variations for D1-D1' and Box B domain, while V3 domain was almost identical among entire species of Nodosilinea, including the studied strains. In addition, a unique morphological character, i.e. forming nodule or spiral shape, was also observed in certain studied strains. According to polyphasic characterization, Nodosilinea coculeatus sp. nov. and Nodosilinea terrestrialis sp. nov., were proposed as two new species of terrestrial cyanobacteria from Okinawa.

• 한국환경복원기술학회지
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• 제20권6호
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• pp.1-19
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• 2017

This study set out to identify problems with amphibian habitation by the wetland types and improve their habitation environment in urban forest wetlands, thus creating a habitat for amphibians. Study site include forest swamps in Jatjul Park as well as Yeoji neighborhood Park in Guro-gu, and in Choansan neighborhood Park in Dobong-gu. The forest swamp in Jatjul Park gets its water from Mt. Maebong and it is a former escalated farmland-turned wetland. The swamp area is $2,500m^2$, a forest zone and a landscape planting site are 83.27% and 6.70% each. Target species Seoul pond frogs are inseparable from rice fields because they live in a short radius of and lay eggs in or near paddy fields, and Rana nigromaculata have similarities with Rana plancyi chosenica in choosing their habitats. There was need for paths that would lead to other paths so amphibians would spread to other parts of the forest and for measures to secure open water. Modifying a variety of routes for water, human and animals along with building a buffer to keep the core habitation zones were required. The forest swamp in Yeonji neighborhood Park used to be a water reservoir on the foot of Mt. Gunji. The swamp area is $1,980m^2$, a forest zone and farmland account for 80.61% and 4.88% each. Non-point pollutants from upstream along run into the subject forest marsh, bare ground on the around swamp and steep stone embankments obstructed amphibians. Target species was Bufo gargarizans that live in forests and edges of hills and spawn in deep water. The forest swamp in Choansan neighborhood Park gets its water from Mt. Choan and it is close to its water source that it is a mountain stream forest wetland. The basin and the swamp are $35,240m^2$ and $250m^2$ in size respectively. A forest zone accounts for 90.20%, high stone embankments laid in refurbishing the valley obstruct amphibians and there is water shortage in times of droughts. Target species were Rana coreana, Rana dybowskii and Hynobius leechii that live in mountain valleys, streams and wetlands and lay eggs in forest marshes and rocks in valleys. Looking into the three swamps of amphibian habitation, I came to conclusions that those wetlands were suitable for their amphibians but man-made facilities blocked their corridors leading to other corridors and even killed off target species in some parts of those swamps by destroying those parts. Amphibians live in water, on ground and underground at different stages of life. Hence, we should take this fact into consideration when planning their habitats and design core habitation zones, buffers zone and use zones accordingly. Buffer zones ought to be between core habitation zones and surrounding trees. Aiming at protecting core habitation zones, buffers should be in harmony with habitation zones. Use zones should be minimized in size and not in direct contact with core habitation zones.

• 환경영향평가
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• 제6권2호
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• pp.153-164
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• 1997

This study was conducted to develop the new Environmental Impact Assessment techniques for the grading of rareness in plant. 17 EISs which were submitted in 1996 were analyzed to know the problems in existent EIA techniques for the conservation of rare plants. Category of rare plant was reevaluated and evaluation technique for the grading of rareness in plant was developed. The results obtained from this study were as follows: 1. The evaluation technique of rareness in plant was not reflected in the current preparation provision for EIS. And t his fact also appeared in most of the EIS which were reexamined in this study. 2. The category of rare species which have been considered as the subject of protection in EIA have to be enlarged to more than legally protected species designated by MOE. 3. The taxonomic characteristics and status of species, characteristics of population, geographical characters, extent of threat and its possibility by man resulted from the habitat loss were investigated. Each item was endowed scores from 1 to 5 and all the scores were summed, and then this value was used to evaluate the order of conservation. 4. Conservation measures for the rare plants have to be applied according to the levels of rareness grade, and they are absolute conservation, in situ conservation, transplanting and ex situ conservation, post observation and none by the levels from A to E. 5. Considering the phenology of rare plants, investigation for the rare plants have to be made a1 least three times. 6. Size of the MVP(Minimum Viable Population), pollination ecology also have to be considered for the conservation of rare plants. And in the case of adopting ex situ conservation measure, the site and methods for the conservation of rare plants have to be proposed in detail.

• 한국습지학회지
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• 제11권3호
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• pp.115-132
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• 2009

댐의 습지로서의 기능을 평가하기 위해 댐도 하나의 습지로 정의하고, HGM 습지 평가 방법에 따라 보령댐을 우포늪의 습지 기능을 비교 평가하였다. 보령댐의 습지로서 수문학적 기능은 단기적이고 작은 흐름들에 대해서는 취약성을 가지지만, 반면 장기적이고 큰 흐름들에 대해서는 강점을 가진다. 생지화학적 기능은 우포의 약 50%정도를 수행하는 것으로 나타났다. 식물 서식처로서의 기능도 식물 군집의 유지 측면에서 매우 우수한 기능을 하는 것으로 나타났다. 동물 서식처로서의 기능은 우포늪에 준하는 기능을 수행하였다. 다만 조류의 서식처로서의 기능이 다소 부족하였다. 이 연구를 통해 보령댐의 장점과 단점을 명확히 하여 장점을 살리고 단점을 보강 할 근거를 마련하고자 한다.

• 한국환경복원기술학회지
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• 제20권4호
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• pp.63-75
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• 2017

This study carried out for establishing the synthetic restoration plan to improve ecological quality of Mt. Mudeung National Park based on the results of conservation value assessment for yellow-throated marten habitats. Yellow-throated marten has significant implications as umbrella species for the wildlife habitats conservation, therefore, this species could be used to ecological restoration plan of the damaged forest ecosystem in Mt. Mudeung National Park. In this study, we diagnosed the quality of yellow-throated marten habitats in Mt. Mudeung National Park based on five natural and two artificial factors. In addition, we evaluated the integrity of each zone divided by trails quantitatively based on land use intensity. As a result, forest landscape quality in Mt. Mudeung National Park was influenced greatly by human activity and the degree was depended on the intensity of trails. Therefore, in this study, we suggested the closing of trails composed of the illegal and 36 legal trails. And then, we modeled the changes of habitats quality of Yellow-throated marten for each closing step. As a result the area of core habitats increased by two times and wildlife habitats quality improved in the whole area of the Mt. Mudeung National Park. As a result, the results of this study indicate that man-made linear landscape elements play a key role in the quality of habitats for predators, which require large habitats area like the Yellow-throated marten. Therefore, in order to establish an ecological restoration plan in the mountainous area, we recommend the concept of the linear landscape should be applied with the concept of area landscape.

• Parasites, Hosts and Diseases
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• 제21권2호
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• pp.193-204
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• 1983

The Jinyang Lake is dammed up Nam River, and surrounded by Jinju city and four counties; Jinyang, Sanchong, Hading, and Sachon in kyongsang-Nam-Bo, Korea. The areas around this man-made lake have been known as an endemic focus of clonorchiasis in Korea. The present study was first aimed to know the distribution of freshwater mollusks including medically important snails, and larval trematodes shed from Parafossarulus manchouricus and Semisulcospira libertina. In addition to above studies, water analyses in each snail habitat were carried out in order to figure out a part of their environmental factors. This malaco-ecological survey was done at the sirs areas around upper, middle and lower parts of the lake for 4 months, August-November, 1983. Total nine species of freshwater mollusks were collected throughout the study: 4 species of gastropods: Semisulcospira libertina, Cipangopaludina chinensis, Parafossarulus manchouricus and Radin auricularia, and 5 species of bit.alves; Unio dcuglasiae, Ancdonta woodiana, Lamprotula gottschei, Corbicula yuminea and Limncperma lucustris. Out of nine species of freshwater mollusks, three species of gastropods; S. Zibertina, p. manchouricus and R. auricularia were medically important in terms of the transmission of digenetic trematodes to humans. P. manchouricus and R. auricularia were mainly collected from the shallow ponds and the irrigation channels with the muddy basin, but S. libertine and the bivalves were only collected from the stream of Nam River where the gravels and rocks were dominant. The levels of dissolved oxygen (D.O.) and biochemical oxygen demand \(B.O.D._5)\ of the water specimens sampled from the study areas ranged from 6.0 to 9.6 ppm and from 0.4 to 1.6 ppm respectively. As a result, it is considered that water system around the Jinyang Lake might be relatively clean without any heavy pollution of aquatic microorganisms and organic materials during the period of this study. On the other hand, eight metalic constituents from the water samples were also assayed, and all metalic ions detected were remarkably low below the legal criteria. However, calcium ion in the water samples from the habitats of P. manchouricus was considerably higher than others. Infection rates of digenetic trematodes in the snails were 6.9% in P. manchouricus and 4.8% in S. libertine, respectively. P. manchouricus snails harboring with thc cercariae of Clonorchis sinensis were only 0.14% among the snails examined, and other trematode cercariae except cercaria of C. sinensis were: furcocercus cercariae, cercaria of Loxogenes liberum type I and II. S. libertine snails parasitized with the cercariae of Metagonimus yokogawai were 1, 5% out of the snails examined, and no cercaria of Paragonimus westermani was found in S. libertine snails in the present study. Digenetic trematode cercariae other than M. yokogawai observed in S. libertina snails were: Cercaria yoshidae (B type) , Cercaria cristata, Cercaria innominatum, Cercaria of Centrocestus formosanus and Cercaria nipponensis.

• 한국조경학회지
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• 제27권3호
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• pp.1-17
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• 1999

The purpose of this study is to evaluate the creation techniques of artificial wetland, one of biotopes developed to promote biodiversity in urban areas, and to look for improvement steps. Specifically, artificial wetland creation techniques were categorized into living environment and living creature classification. Being living conditions for creations, habitat environment was reviewed with a focus on water and soil environments. Living creatures were classified into plants, insects, fish, and birds. The evaluation of creation techniques was done in post-construction evaluation while considering the creation of habitats for living creatures. Intervention by users, changes in living environment and living species, and relevance of creation techniques were reviewed. Key results of this study are as follows. (1) Water environment for the living environment of creatures provides a suitable environment conditions for the living of creatures through a process easing the use of piped water. Various water depths and embankment appear to have a positive impact on the living of aquatic life. In particular, embankment covered in soil naturally played an important role as a place for the activities of aquatic insects and young fish as well as the growth of aquatic plants. (2) Various aquatic and ground plants to promote insect-diversity, shallow water, and old-tree logs had contributed greatly in increasing the types and number of insects. Aquatic insects. Aquatic insects were seen much particularly in areas where aquatic plants are rich but water is shallow than any other areas. (3) A space piled with stone to provide habitats for fish was not much used. However, it was observed that fish used embankment built with natural stones and embankment using logs in areas where water is deep. In addition, it was confirmed that 1,500 fish that had been released propagated using various depths and places for birth. (4) It was analyzed that techniques (creation of island, log setting, and creation of man-made bird nests) to provide habitats and to attract birds are not serving their roles. In such a case, it is believed that species had not increased due to the smallness as well as isolated features of the area. Based on theoretical review, they are judged to be areas that are likely to be used when a greater variety of birds is introduced. It is judged that attracting and keeping more birds at the site, such spaces need to be linked systematically in the future in terms of building eco-network while ensuring an adequate living areas. (5) In the study areas, users intervened greatly. As a result, a blockage was created preventing the normal growth of plants and non-indigenous plants were introduced. In order to limit the intervention by users, setting enough buffer zones, and environment education programs were urgently required. D/H=1>Hyangkyo> houses on the river>temples>lecture halls. D/H ratio of the backside areas is as follows. D/H=1>Hyangkyo>houses on the river>lecture halls. 4. Inner garden were planted deciduous than evergreen trees with Lagerstroemia indica. Enclosed dominant trees were planted by Pinus densiflora, Querces seuata. construct GEM strain, and examined for the expression and functional stability in microcosms.