• 제목/요약/키워드: a parcel under the sea

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Investigation of the Collapsed Lands Under the Sea Based on Cadastral and Topographic Survey

  • Lee, Chang-Kyung;Han, Sang-Deuk
    • Korean Journal of Geomatics
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    • 제2권2호
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    • pp.91-98
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    • 2002
  • Lands along the coast may be submerged in high water because of erosion by sea water, collapsing by itself, excavation by animals, and by tidal movement. From a cadastral point of view, some mistakes in registering a parcel located along the coast may cause the parcel to seem to be collapsed. Therefore, geological, physical oceanographic, and cadastral and topographic investigation are necessary to verify that the submerged land in high water collapsed after it was registered. This paper presents a cadastral and topographic investigation for proving a parcel has collapsed under the sea after registered. In this study, cadastral records and the boundary on cadastral maps were examined carefully to find any errors in them. If the topographic maps were drawn when the parcel was registered, it is good proof of topography of the land at that time. Topographic maps drawn recently were compared to those in the 1900s and in 1970s. In conclusion, cadastral records and maps as well as topographic maps play an important role in proving whether lands along the coast were collapsed or not.

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정사항공사진과 해양조사측량을 이용한 해안선변화탐지에 관한 연구 : 포락지 중심으로 (The Study of Coastal Change from Using Ortho Aerial Photo and Hydrographic Survey : the Parcel under the Sea)

  • 최철웅;서영찬;양지연;박소영
    • 한국지형공간정보학회:학술대회논문집
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    • 한국지형공간정보학회 2004년도 추계학술발표대회 논문집
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    • pp.167-173
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    • 2004
  • 연안의 무분별한 개발에 따른 후유증으로 침식(또는 퇴적) 현상은 심각한 수준에 이르렀다. 해안선 변화는 광범위한 지역을 대상으로 장기간 서서히 진행되어 원인규명 및 대책제시에 오랜 연구가 필요하다. 특히 기후온난화 결과로 향후 1백년 내에 전체 지구해수면이 평균 $19{\sim}35cm$ 상승할 것으로 예상되어 연안환경변화에 대비 지속적인 해안선 변화에 관한 연구가 필요하다. 본 연구에서는 정사항공사진과 해양조사측량 자료를 이용하여 해안 침식과 퇴적 경향을 정량적으로 분석하고 해안선변화에 따라 발생하는 포락지 발생여부를 판정할 수 있었다. 이를 위해, 약 10년 주기로 정사항공사진을 제작하고 토지임야도를 중첩시켜 조위를 고려하였을 때와 고려하지 않았을 때의 침식 및 퇴적량을 산출하였다. 본 연구결과, 장기해안선 변화탐지에 정사항공사진기법과 해양조사 측량을 이용하는 것이 침식 및 퇴적, 인공매립 등의 유효한 변화탐지 기법임을 알 수 있었다.

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부산지역 여름철 고농도 PM2.5 농도 사례와 기상학적 관련성 (Characteristics of Summertime High PM2.5 Episodes and Meteorological Relevance in Busan)

  • 전병일
    • 한국환경과학회지
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    • 제29권7호
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    • pp.761-772
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    • 2020
  • This research investigated the meteorologically relevant characteristics of high PM2.5 episodes in Busan. The number of days when daily mean PM10 concentration exceeded 100 ㎍/㎥ and the PM2.5 concentration exceeded 50 ㎍/㎥ over the last four years in Busan were 24 and 58, respectively. Haze occurrence frequency was 37.6% in winter, 27.4% in spring, 18.6% in fall, and 16.4% in summer. Asian dust occurrence frequency was 81.8% in spring, 9.1% in fall and winter, and 0% in summer. During summer in Busan, high PM2.5 episode occurred under the following meteorological conditions. 1) Daytime sea breeze. 2) Mist and haze present throuout the day. 3) Anti-cyclone located around the Korean peninsula. 4) Stable layer formed in the lower atmosphere. 5) Air parcel reached Busan by local transport rather than by long-range transport. These results indicate that understanding the meteorological relevance of high PM2.5 episodes could provide insight for establishing a strategy to control urban air quality.

발달 단계의 축대칭 열대저기압의 각운동량에 관한 연구 (Study on the Angular Momentum of Axisymmetric Tropical Cyclone in the Developing Stage)

  • 강현규;정형빈
    • 대기
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    • 제23권1호
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    • pp.1-11
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    • 2013
  • The angular momentum transport of an idealized axisymmetric vortex in the developing stage was investigated using the Weather Research and Forecast (WRF) model. The balanced axisymmetric vortex was constructed based on an empirical function for tangential wind, and the temperature, geopotential, and surface pressure were obtained from the balanced equation. The numerical simulation was carried out for 6 days on the f-plane with the Sea Surface Temperature (SST) set as constant. The weak vortex at initial time was intensified with time, and reached the strength of tropical cyclone in a couple of days. The Absolute Angular Momentum (AAM) was transported along with the secondary circulation of the vortex. Total AAM integrated over a cylinder of radius of 2000 km decreased with simulation time, but total kinetic energy increased rapidly. From the budget analysis, it was found that the surface friction is mainly responsible for the decrease of total AAM. Also, contribution of the surface friction to the AAM loss was about 90% while that of horizontal advection was as small as 8%. The trajectory of neutral numerical tracers following the secondary circulation was presented for the Lagrangian viewpoint of the transports of absolute angular momentum. From the analysis using the trajectory of tracers it was found that the air parcel was under the influence of the surface friction continuously until it leaves the boundary layer near the core. Then the air parcel with reduced amount of angular momentum compared to its original amount was transported from boundary layer to upper level of the vortex and contributed to form the anti-cyclone. These results suggest that the tropical cyclone loses angular momentum as it develops, which is due to the dissipation of angular momentum by the surface friction.

여름철 북태평양고기압 하에서 사쿠라지마 화산 분출(2018년 7월 16일)이 부산지역 초미세먼지 농도에 미치는 영향 (Effect of Sakurajima Volcanic Eruption (July 16, 2018) on PM2.5 Concentration in Busan under Summertime North Pacific High Pressure Condition)

  • 전병일
    • 한국환경과학회지
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    • 제31권6호
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    • pp.503-513
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    • 2022
  • This research investigated the effect of the eruption of Japan Sakurajima volcano on the concentration of ultrafine particle when the north Pacific high pressure exists in the Busan in summer. As a result of analyzing the forward trajectory using the HYSPLIT model, the air parcel from Sakurajima volcano passed through the sea in front of Busan at 1500 LST on July 17, 24 hours after the volcanic eruption. As a result of analyzing the PM10 and PM2.5 concentrations in the Busan for two days from July 16 to 17, 2018, the Sakurajima eruption in Japan, it can be seen that there was a high increase in PM10 and PM2.5 concentrations compared to the previous day. As a result of analyzing the backward trajectory, the air mass that reached Busan at 1300 LST on July 17, 2018 has moved near the Sakurajima volcano at 1,500 m, 2,000 m, and 3,000 m. The concentration of SO42- in PM2.5, the concentration of all three stations in Busan showed a sharp increase from 1000 LST on July 17th. Looking at the NH4+ concentration in PM2.5, it shows a very similar variation trend to SO42-, and the correlation coefficient between the two components is 0.96 for Jangrimdong and Yeonsandong, and 0.85 for Busan New Port. Looking at the NO3- concentration in PM2.5, the same high concentrations as SO42 and NH4+ were not observed in the afternoon of July 17th.