• 한국항공운항학회지
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• 제29권1호
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• pp.1-8
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• 2021

Low level wind shear, which often occurs at Jeju International Airport, is a phenomenon that occurs when the topological location and topographical characteristics of Jeju Island are combined with weather characteristics. Low level wind shears, which are caused by rapid changes in wind direction and wind speed, pose a threat to aircraft safety and also cause abnormal situations, such as aircraft go-around, diversion, and cancellation. Many meteorological studies have been conducted on weather patterns, occurrence periods and frequency of low level wind shears. However, researches related to aircraft operations are limited where here we study the similarities and differences between strong southwest winds and bidirectional tailwind type low level wind shears based on aircraft go-around cases at Jeju International Airport. The results are expected to be used to enhance safety when operating to Jeju International Airport, which includes pilot training that reflects the characteristics generated by wind changes, pilot prior notification, providing pilots with latest trends, and increasing extra fuel.

• 한국해양학회지:바다
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• 제17권4호
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• pp.203-224
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• 2012

실질적인 하구환경의 관리를 위해서는 관리구역, 즉 하구역이 먼저 정의되어야 한다. 그러나 하구역의 경계를 설정할 수 있는 과학적 자료의 부족으로 인해 아직까지 체계적인 경계설정 방법이 제시되지 못하고 있다. 본 연구는 하구의 물리화학적 특성 등의 과학적 자료와 더불어 지리 지형적 특성 및 이용개발 특성 등을 종합적으로 고려하여 체계적으로 하구역 경계를 설정하는 방법을 제안하였다. 하구를 하구순환의 유지여부에 따라 열린 하구와 닫힌 하구로 구분하고, 각 유형에 속한 개별 하구에 대해 물리화학, 지리지형학 및 이용개발 특성을 고려하여 하구수역의 경계를 설정한 후에 하구수역에 영향을 미치는 하구육역의 경계를 설정하는 순차적인 방법이다. 이 방법에 따라 국내 274개 하구역의 경계를 시범적으로 설정해본 결과 각 하구별로 가용한 자료의 수준과 지역 특성의 차이를 합리적으로 고려한 하구역 경계 설정이 가능한 것으로 나타났다.

• 한국환경복원기술학회지
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• 제6권4호
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• pp.62-73
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• 2003

The study was to apply a mat style reed planting method at confluence to improve plants growth conditions by relaxing disturbed topographical base due to water flow and was intended to review the effect to build up a vegetation strip by monitoring process after the construction. First off, We've attempted to construct reed mats on selected sites as confluences of Tan and Gaehwa stream and then examined and analyzed characteristics of soil and vegetation community. As the results of the examination, the soil texture was proven to be a mix of sand and loamy sand and be 6.3 ~ 7.0 soil pH. In addition, it contained 1.0 ~ 4.6% of organic matter, 0.04 ~ 0.22% of T-N and 27.8 ~ 41.2% of water content. For its vegetation structure, the Tan stream confluence was first actually a point bar without plants prior to the construction but 8 kinds of hygrophytes including Persicaria hydropiper and 9 kinds of terrestrial plants such as Potentilla supina, Artemisia annua, and Alopecurus aequalis var. amurensis. On the other hand, the Gaehwa stream confluence contained 6 kinds of hygrophytes such as Bidens frondosa and other 11 kinds of terrestrial plants prior to the construction while it produced 7 kinds of hygrophytes including Ranunculus ternatus as well as Phragmites australis and 9 kinds of terrestrial plants such as Potentilla supina after the construction. For the Phragmites australis, almost of them was weathered away in early days just after planting because of development period passed, but on May, six months later from planting, it was investigated that its length was approximated as 65 ~ 85cm with 75% coverage and that the number of it was 437 ~ 633/$m^2$. The study was shown that reed mats can improve environmental conditions of disturbed topographical base, enabling natural growth of various riparian vegetation including the introduced plant, reed. In the meantime, it was supposedly judged that to recover or build up a vegetarian strip, supplementary materials should be prepared to help produce and grow plants because it is not probable to expect river drift by water flow at confluence and that corrosion, burying or inundation owing to changes of water lever should be considered.

• 한국산림과학회지
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• 제82권2호
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• pp.195-206
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• 1993

본 연구는 임업기계화(林業機械化)의 전제조건인 지역별(地域別) 산림수종체계(山林收種體系)를 수립하기 위한 기초연구로 시도되었다. 이를 위하여 산림수확방법(山林收穫方法)과 집재방법(集材方法)들을 제어(制御)하는 인자들이 무엇인가를 특히 지형적(地形的)인 관점에서 조사하고 분석하였다. 주요한 산림수확방법은 단재수확법(短材收穫法), 장재수확법(長材收穫法) 및 전목수확법(全木收穫法)이다. 단재수확법은 지형조건(地形條件)이 열악(劣惡)한 산림(山林)에, 전목수확법은 양호(良好)한 산림(山林)에, 그리고 장재수확법은 중간조건(中間條件)의 산림(山林)에 적용됨이 조사되었다. 집재방법(集材方法)에 대해서는 육상집재법(陸上集材法)을 중심으로 검토하고 주요 집재법으로는 축력집재(畜力集材), 인력(人力) 및 중력(重力) 집재(集材), 차량집재(車輛集材), 그리고 강선집재(鋼線集材) 등이다. 강선집재 중 케이블 크레인에 의한 집재는 집촌거리(集村距離)에 따라 단거리(短距離)(300 혹은 400m까지), 중거리(中距離)(700 혹은 800m까지) 및 장거리(長距離)(700 혹은 800m 이상) 등으로 구분한다. 집재작업범위(集材作業範圍)를 제어하는 인자는 경사(傾斜)와 집재거리(集材距離)이다. 차량집재(車輛集材)는 산림에 큰 부하(負荷)를 주며, 중력집재(重力集材) 중 log-line과 강선집재(鋼線集材) 중 케이블 크레인에 의한 집재법은 산림훼손(山林毁損)을 최소화(最小化)한다. 차량집재는 경사가 급할수록 어려워지고 케이블 크레인 집재는 120%까지 가능하다(상향집재(上向集材)).

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.1182-1186
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• 2006

하천유역에 있어 설계홍수량의 결정은 치수적인 측면에서 매우 중요한 일이다. 유역의 대소와 중요도에 따라서 하천의 설계홍수량이 산정이 된다. 갈수록 홍수의 피해정도가 심해지고 홍수에 대한 방어의 중요성이 더욱 가중되고 있는 현실에서 설계홍수량의 추정은 매우 중요하다고 할 수 있다. 특히 홍수량을 산정하는 데 있어 가장 큰 영향을 미치는 것은 강우량이다. 그러나 똑같은 강우량이라 할지라도 유역의 특성에 따라 산정되는 홍수량은 상이하게 된다. 유역의 특성이 홍수량의 산정에 있어 영향이 크다는 것은 선행 연구의 결과와 경험에 의하여 확인이 된 사실이다. 그러나 많은 하천들이 각각의 유역특성을 가지고 있으나 이들과 산정된 설계홍수량의 관계가 어떤 형태로 이루어져 있는 가에 대한 연구는 아직 미흡한 실정이다. 본 연구에서는 기왕에 하천정비기본계획에 의해 산정된 설계홍수량과 지형인자들이 어떤 상관성을 가지고 있는 가에 대하여 연구하여 미계측유역이나 하천계획이 수립되지 않은 중소하천 유역의 설계홍수량 추정에 있어 추가적인 정보의 제공측면에서 유역의 지형인자와 설계홍수량과의 상관성을 조사하였다.

• Journal of Astronomy and Space Sciences
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• 제33권1호
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• pp.21-28
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• 2016

Caves can serve as major outposts for future human exploration of the Moon and Mars. In addition, caves can protect people and electronic equipment from external hazards such as cosmic ray radiation and meteorites impacts and serve as a shelter. Numerous pit craters have been discovered on the Moon and Mars and are potential entrances to caves; the principal topographic features of pit craters are their visible internal floors and pits with vertical walls. We have devised two topographical models for investigating the relationship between the topographical characteristics and the inner void of pit craters. One of our models is a concave floor void model and the other is a convex floor tube model. For each model, optical photographs have been obtained under conditions similar to those in which optical photographs have been acquired for craters on the Moon and Mars. Brightness profiles were analyzed for determining the profile patterns of the void pit craters. The profile patterns were compared to the brightness profiles of Martian pit craters, because no good-quality images of lunar pit craters were available. In future studies, the model profile patterns will be compared to those of lunar pit craters, and the proposed method will likely become useful for finding lunar caves and consequently for planning lunar bases for manned lunar expeditions.

• 농촌계획
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• 제1권2호
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• pp.77-92
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• 1995

The initiative to determine farmland use has been transferred to local side under the decentralized government system in Korea. New Land Act and Rural Development Act support it. Changes in external and internal environments of Korean agriculture require to diversify farmland use. Lpcal development plan may be implemented when specific farmland use plan is prepared. However, (armland use planning has not been prepared by the local governments yet. This study aims to identify problems encountered in current farmland use and suggest directions of effective and reasonable farmland use planning relevant to local conditions. Questionnaire method was used to prove topographical differences of community land demand, Statistical analyses show that farmers desire to utilize marginal farmland for income increase. Growing grass(42.0%) and cash crops(41.7%) was greatly demanded by them. They were generally eager for developing touristic farm (52.1 % ). By topographical characteristics, the eager was greatest in coastal areas, on the contrary, it was relatively low in mountainous areas. There were more farmers who want to expand their farmland in rice farming(48.4%) or rice-horticulture farming(46.9%) areas. Potential retirer among farmers were most in suburban areas, However, it was expected that there would be the highest retirement rate in rice farming areas because of the high rate of aged farmers. Farmland use planning should be incorporated into food production policies and community people's needs for income increase and life improvement. Agriculture promotion areas must be maintained for scale optimized farming and cash crop farming as much as possible. However, minimum portion for other uses in each village or farming community unit should be adopted. Less favored areas will have to be utilized for both agriculture and non-agriculture uses. Priority can be put into touristic resorts as a non-agriculture use. Furthermore, such areas can be used for sustainable agriculture as well as for residence, industry, animal breeding.

• 건축역사연구
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• 제23권5호
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• pp.47-60
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• 2014

Urban-Hanok emerged as a result of urbanization of Hanok in the modern period. In particular, Urban-Hanok has been mass-produced from the early 1920s, when the population is concentrated in cities, until the middle. Large-scale development by the professional developer has been developed in large-scale land rather than individual client because housing shortage was serious problem. 11 Gahoe-dong was made in 1935-36 is representative Urban-hanok area of Bukchon. It was formed through division of large-scale Land in 1930's. In the 1930's, the large-scale development projects of Urban-Hanok was triggered by the two events. One is Land Investigation Project performed by the Japanese government to capitalization of property, another is the pro-japanese bought the large scale-land in Gahoe-dong at bargain price from The Japanese government. Each lot has still a topographical characteristics such as land-dividing quality, the way of development, characteristic quality of urban-tissue. 11 Gahoe-dong, Urban-hanok area was developed two ways. First, development have been adapted to the topography. The lots have reflected topographical conditions such as land cutting area, a retaining wall, land-diving was maintaining the original topography almost. Second, it was street oriented development. The lots have developed sequentially along the street. So, the lots's shape and size is different each. For this reason, this area distribute various type of Hanok.

• Journal of Ginseng Research
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• 제4권2호
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• pp.175-185
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• 1980

A study was made to clarify the topographical. and Physical characteristics of ginseng field in terms of soil science and to find the relationship between soil characteristics and ginseng growth, as well as yield of ginseng roots Forty nine farmer's red ginseng field of ginseng growing area were chosen for this study and investigated for two years. The results obtained were as follow. 1. Ginseng fie1ds with high yield which represent the more than 1.8kg of ginseng root per 3.2m2 were found in soil series of Bancheon, Yeongog, Weongog, etc. whose texture were the clay loam to clay soil. On the other hand, ginseng field with low yield were observed in soil series of seogto whose texture was loamy soil with high content of gravels. 2 Soil of ginseng field with high yield had higher content of clay. silt soil moisture and soil pore as compared with soils of low yields. These soil characteristics were positively correlated with stem length stem diameter and root weight of ginseng plsnt and negatively correlated with rate of missing plant 3. The adequate ranges of soil 3 phase from high yield ginseng field were 40 to 50% of solid Phase, 22 to 35% of liquid phase, 25 to 35% of gaseous phase in top soil and 45 to 55% of solid phase. 28 to 30% of liquid phase. 15 to 20% of gaseous phase in subsoil respectively.

• 산업기술연구
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• 제28권A호
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• pp.3-10
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• 2008

This paper is to investigate the characteristics of debris flow landslides in Gangwon Province through literature review, data collection and analyses and site investigation. As results of data analyses about landslides occurred currently in this province, the landslide in the form of debris flow is found to be 55 %. Therefore major loss and costs are caused by discharge of soil and rock fragments from landslide. From results of analyzing the geometrical characteristics of landslide, length of most of landslide is less than 200 m, their width is in the range of 10 - 40 m, most of them are know to be occurred in lower elevation than 400 m. Slope angle is in the range of 25 - 35 degrees. Comparing the period of rainfall intensity with the time of landslide being occurred, occurrence of landslide is quite related to duration of a heavy rainfall. For measures of controlling water flow discharge and debris flow, considering geological and topographical ground conditions, appropriate selection and building check dam, erosion control dam and ring net is very beneficial for reducing the loss and costs caused by the landslide of debris flow.