• 제목/요약/키워드: Seashore

검색결과 314건 처리시간 0.032초

사초과 하늘지기속의 한국 미기록종: 바위하늘지기(Fimbristylis hookeriana Boeckeler) (First record of Fimbristylis hookeriana Boeckeler (Cyperaceae) from Korea)

  • 김종환;김무열
    • 식물분류학회지
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    • 제43권4호
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    • pp.296-299
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    • 2013
  • 한국 미기록 종인 바위하늘지기(Fimbristylis hookeriana Boeckeler)를 전라남도 영광군과 전라북도 군산시 무녀도에서 발견하였다. 바위하늘지기는 식물체에 털이 없고, 소수가 매우 좁은 난형이며, 암술대가 길고, 인편이 탈락하지 않고 늦가을까지 숙존하는 특징을 가지고 있는데 반하여, 하늘지기는 식물체에 털이 있고 소수가 난형이며 인편이 탈락하는 점에서 구별된다. 이 미기록종의 국명은 주로 바닷가 근처의 건조한 바위위에 자라기 때문에 '바위하늘지기'로 하였고, 바위하늘지기에 대한 기재, 도해, 사진 및 근연종 사이의 차이점을 검색표와 표로 제시하였다.

시간의존성을 고려한 해안가 철도 콘크리트 구조물에 대한 내구성 설계 기법의 개발 (Development of Durability Design for Railroad Concrete Structures Exposed to Marine Environment Considering Time Dependency)

  • 송하원;백승우;이선호;권진수;이현정
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1431-1438
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    • 2007
  • This paper presents a refined design model for current railroad design code on concrete structures exposed to marine environment. A time-varying diffusion coefficient(D) as well as surface chloride$(C_S)$ and chloride threshold level$(C_{lim})$ are studied. Averaging value of the D with time over exposed duration were used to refined durability design model to consider time dependent characteristic of D. The values for $C_S$ and $C_{lim}$ for the seashore in Korea revised for realistic durability design. The proposed model was verified by the so-called performance-based durability design, which is widely used in recent durability design code. Results show that the current standard specification underestimates durability performances of concrete structures exposed to marine environment, so that the cover depth design using current durability evaluation in the standard specifications is very much conservative. Thus, it is found that proposed durability design models for the railroad design code for railway concrete structures can be used effectively for service life design of concrete structures in marine environment.

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해안형 국립공원의 보전체계에 대한 한.일 비교 - 태안해안 국립공원을 중심으로 - (Comparison Between Conservation System of a Coastal Type of National Park of Korea and Japan - Focused on Taean-Haean National Park -)

  • Jo, Tae-Dong;Okano, Takahiro
    • 한국환경과학회지
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    • 제12권2호
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    • pp.151-155
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    • 2003
  • The resources conservation system is comprehended, making Taean-haean National Park a research material by applying the fact of landowning, designating an LOP and Korea and Japan's Natural Park Act. Following conclusions were obtained in this study; Most of land areas of the National Park are privately owned; Only a few have been designated as Natural Reservation, a core reserved area on LOP, and a sandy beach, a sand dune, a sand spit, a tidal flat, a wetland, etc are distributed in the natural environment area so they were exposed to development; As seen in most of coastal type of National Parks, 13 commercial beaches are established. The annual rush to the beaches appears in July and August; Sand dune areas that have to be managed in terms of conservation, are turned into beaches. Moreover, the collective facilities areas are randomly developed. So they fail to function originally; The current Natural Park Act has no systematic devices for conservation of the natural resources on the seashore or offshore.

해수면온도와 식생효과를 고려한 연안도시지역의 대기환경예측 (Atmospheric Environment Prediction to Consider SST and Vegetation Effect in Coastal Urban Region)

  • 지효은;이화운;원경미
    • 한국환경과학회지
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    • 제18권4호
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    • pp.375-388
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    • 2009
  • Numerical simulation is essential to indicate the flow of the atmosphere in the region with a complicated topography which consists of many mountains in the inland while it is neighboring the seashore. Such complicated topography produces land and sea breeze as the mesoscale phenomenon of meteorology which results from the effect of the sea and inland. In the mesoscale simulation examines, the change of the temperature in relation to the one of the sea surface for the boundary condition and, in the inland, the interaction between the atmosphere and land surface reflecting the characteristic of the land surface. This research developed and simulated PNULSM to reflect both the SST and vegetation effect as a bottom boundary for detailed meteorological numerical simulation in coastal urban area. The result from four experiments performed according to this protocol revealed the change of temperature field and wind field depending on each effect. Therefore, the lower level of establishment of bottom boundary suitable for the characteristic of the region is necessary to figure out the atmospheric flow more precisely, and if the characteristic of the surface is improved to more realistic conditions, it will facilitate the simulation of regional environment.

산지 내 오염물질 확산의 2차원 수치해석 (Numerical Analysis of the Two-Dimensional Pollutant Dispersion Over Hilly Terrain)

  • 김현구;이정묵
    • 한국대기환경학회지
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    • 제13권5호
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    • pp.383-396
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    • 1997
  • Numerical prediction of the pollutant dispersion over a two-dimensional hilly terrain is presented. The dispersion model used in the present work is based on the gradient diffusion theory and the finite-volume method on a non-orthogonal boundary-fitted grid system. The numerical model is validated by comparing the results with the available experimental data for the flat-floor dispersion within a turbulent boundary-layer. The numerical error analysis is performed based on the guideline of Kasibhatla et al.(1988) for the elevated-source dispersion in the flat-floor boundary layer having a power-law velocity and linear eddy-diffusivity profile. The influences of the two-dimensional hilly terrain on the dispersion from a continuously released source are numerically investigated by changing the emission locations and heights. It is found that the distributions of ground-level concentration are strongly influenced by the source location and the emission height. Hence, the terrain amplification factor is greatly enhanced when the pollutant source is located within a flow separation region. Dispersion from a source of short duration is also simulated and the duration time of the pollutant is compared at several downstream locations on a hilly terrain. The results of the numerical prediction are applied to the evaluation of environmental impacts due to the automobile exhausts at the seashore highway with a parallel mountain range.

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죽염에 대한 단회투여 독성시험연구 (Single Dose Toxicity Studies of the Bamboo Salt (Jukyum) in rats)

  • 김준규;이봉훈;서경원;박미경;박창원;안진홍;홍충만;조대현
    • Toxicological Research
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    • 제17권4호
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    • pp.273-277
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    • 2001
  • Though the bamboo salt, called as "JUKYUM" has been widely used in Korea as panacea, it's toxicity were not screened completely. To investigate the toxicity of bamboo salt, we compared with the toxicity of crude salt and reagent-grade NaCl by performing single dose oral toxicity test in SD rats. Crude salt, natural sun-dried salt (crude salt) production, was purchased from the western seashore of Korean peninsular, and reagent-grade NaCl was purchased from Sigma company. Results of the single dose oral toxicity tests on bamboo salt, crude salt and reagent-grade NaCl to SD rats are as follows, $LD_{50}$ of bamboo salt was 4174mg/kg (male) and 4074mg/kg (female), that of crude salt was 4871mg/kg (male) and 4898mg/kg (female) and that of reagent-grade NaCl was 4247mg/kg (male) and 4025mg/kg (female), respectively. There were little differences in clinical signs and gross legions among groups. Finding of gross autopsy and necropsy of bamboo salt treated group were similar to other groups.er groups.

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유한요소법을 이용한 3차원 염해 침투 예측 모델의 개발 (Development of Three Dimensional Chloride Ion Penetration Model Based on Finite Element Method)

  • 최원;김한중
    • 한국농공학회논문집
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    • 제57권5호
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    • pp.43-49
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    • 2015
  • Most of agricultural structures located in seashore could not avoid rapid deterioration of concrete because chloride-ion and $CO_2$ gradually penetrate into concrete. However, since most of models can be able to describe the phenomenon of penetration by using one or two dimensional models based on finite difference method (FDM), those modes can not simulate the real geometry and it takes a lot of computational time to complete even the calculation. To overcome those weaknesses, three dimensional numerical model considering time dependent variables such as surface concentration of chloride and diffusion coefficient of domain based on finite element method (FEM) was suggested. This model also included the neutralization occurred by the penetration of $CO_2$. Because the model used various sizes of tetrahedral mesh instead of equivalent rectangular mesh, it reduced the computational time to compare with FDM. As this model is based on FEM, it will be easily extended to execute multi-physics simulation including water evaporation and temperature change of concrete.

읍·면급 섬지역 서비스산업의 구조적 분화 (Structural Differentiation of Rural Service Industries in Korean Island Areas)

  • 박용진;최수명;조은정
    • 농촌계획
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    • 제19권1호
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    • pp.1-10
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    • 2013
  • By the continued island-mainland bridging works, increased consumer demand for seashore regions and fundamental improvement of accessibility to metropolitan areas, rural service industries in the island areas has been rapidly developed in the past decades, and also, their functions differentiated geographically. In most island areas, catering and accommodation sectors have been expanded, while traditional trading sector decreasing. And the dominant power of public sectors has been increased but private ones decreased. So, the overall development trends of service industries in island areas would be considered as unhealthy for rural economic sustainability. As a tentative solution, it may be proposed that through the functional specialization/differentiation and efficient linking/networking of rural service industries with multifunctionality of countryside capitals, their spatial cohesion would be strengthened.

남극 해안으로부터 저온적응 부식산 분해 Pedobacter sp. PAMC 27299의 유전체 서열 해독 (Complete genome sequence of a cold-adapted humic acid degrading bacterium Pedobacter sp. PAMC 27299 from the Antarctic seashore)

  • 김혜진;박재완;박하주;김덕규;설우준
    • 미생물학회지
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    • 제52권3호
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    • pp.388-390
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    • 2016
  • 부식산(humic acid)을 이용하여 저온에서 배양된 Pedobacter sp. PAMC 27299는 남극 바톤 반도(Barton Peninsula) King George Island의 해안가 이끼(moss debris)로부터 분리되었다. 본 연구에서는 Pedobacter sp. PAMC 27299의 유전체 서열을 해독하였으며 크기 6,147,290 bp, G+C 함량 40.54%의 PAMC 27299는 지구 온난화 관련 저온적응 부식산 분해 효소를 보유하는 것으로 확인되었다.

Landsat 영상을 이용한 서해안 지형 변화 추이 분석 (An Analysis on the change in Topography in the West Coast Using Landsat Image)

  • 강준묵;윤희천;강영미
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.275-279
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    • 2004
  • This study was done to detect the topographic and terrain change of the vicinity of the west coast. To make the basic map of the change in topology and terrain, the mosaic images were made using the images from the satellite, which were given the geometric correction based on the GCP (Ground Control Point) and DEM (Digital Elenation Model) data. The accuracy of the images was examined by .empaling them with CCP through 1:25,000's digital map. After that, among the resultant images of the 1970s and 2000s, those of Sihwa, Hwaong and Ansan, the lands reclaimed by drainage were compared to observe the change in the area. From this study, the accuracy of the images of the west coast from satellite could be acquired and the change of the topology and terrain was detected effectively. From the results, it was known that, in case of the land the topological change was not so big due to the development in the reclaimed land or the bare land. In Sihwa, the size of the land was increased 180 $\textrm{km}^2$ and that of the seashore was decreased 110 km. in Hwaong the size was increased 50 $\textrm{km}^2$ and in Ansan the city space was increased 71 $\textrm{km}^2$ due to the formation of the industrial complex.

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