• Title/Summary/Keyword: geographic frame

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A Study on the Sedmentary Facies Change in the Tidal Flat Using High Spatial Resolution Remotely Sensed Data (고해상도 위성영상을 활용한 갯벌 퇴적상 변화 연구)

  • Choi, Jong-Kuk;Ryu, Joo-Hyung
    • Economic and Environmental Geology
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    • v.44 no.1
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    • pp.59-70
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    • 2011
  • The surface sediment distribution in a tidal flat in 2001 was compared with that of 2008 using high spatial resolution remote sensing images and a GIS-based analysis. Maps of the surface sedimentary facies for each time frame were induced by an IKONOS data acquired in February, 2001 and a KOMPSAT-2 data acquired in April, 2008 using an object-based classification method. The area ratio of each surface sedimentary facies were estimated, and the results were compared each other for deducing the change in the sedimentary facies during the time interval. The result showed that the percentage of grains larger than very fine sand (0.0625 mm) has increased considerably since the early 2000s in the Hwangdo tidal flat. Mud flat facies has decreased 5.81 % in the late 2000s compared with the early 2000s. However, mixed flat and sand flat have increased 4.46% and 2.14%, respectively. A field campaign also supported the result. This study showed that the monitoring of changes in the surface sedimentary facies in the tidal flat is possible through a GIS-based analysis using high spatial resolution remote sensing images.

Prevalence of Antibodies to Human Herpesvirus 8 in Children (소아의 항 Human Herpesvirus 8 항체 양성률)

  • Han, Tae Hee;Chung, Ju Young;Kim, Sang Woo
    • Pediatric Infection and Vaccine
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    • v.12 no.2
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    • pp.108-113
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    • 2005
  • Purpose : Human herpsevirus 8(HHV-8), a gamma herpsevirus, was initially identified from Kaposi sarcoma(KS) lesions and has been known to be associated with several malignancies including Kaposi sarcoma. HHV-8 seroprevalence is variable by different geographic areas and populations. The prevalence of HHV 8 infection in Korean children is unclear. So, we investigated the prevalence of HHV-8 specific antibodies in healthy children in Seoul, Korea. Methods : Sera were obtained from 112 children(age 1~15 years, 64 males and 48 females) who visited our hospital for routine health checkup and used for investigating sero-prevalence of anti-HHV-8 antibodies. An indirect immunofluorescent assay was used to detect the IgG antibodies to the lytic viral antigen(Biotrin, Dublin, Ireland). A peptide mix ELISA kit was used to detect the IgG antibodies to peptides specific for HHV-8 open reading frame (ORF)(Biotrin, Dublin, Ireland). Results : Of 112 children, 4 children younger than 6 years of age were seropositive to HHV-8[all 4(3.5%) were positive by IFA and 2(1.8%) were positive by ELISA]. Conclusion : These results suggest that the prevalence of antibody to HHV 8 in children in Korea is very low.

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Improvement of GPS Relative Positioning Accuracy by Using Crustal Deformation Model in the Korean Peninsula (GPS상대측위 정확도 향상을 위한 한반도 지각변동모델 개발)

  • Cho, Jae-Myoung;Yun, Hong-Sik;Lee, Mi-Ran
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.3
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    • pp.237-247
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    • 2011
  • As of 2011, 72 Permanent GPS Stations are installed to control DGPS reference points by the National Geographic Information Institute in South Korea. As the center of the Earth's mass continues to move, the coordinates of the permanent GPS stations become inconsistent over time. Thus, a reference frame using a set of coordinates and their velocities of a global network of stations at a specific period has been used to solve the inconsistency. However, the relative movement of the permanent GPS stations can lower the accuracy of GPS relative positioning. In this research, we first analyzed the data collected daily during the past 30 months at the 40 permanent GPS stations within South Korea and the 5 IGS permanent GPS stations around the Korean Peninsula using a global network adjustment. We then calculated the absolute and relative amount of movement of the GPS permanent stations. We also identified the optimum renewal period of the permanent GPS stations considering the accuracy of relative GPS surveying. Finally, we developed a Korean a Korean crustal movement model that can be used to improvement of accuracy.

Study on Coordinate Transformation of Railroad Central Linear-line Using the Railroad Reference Points (철도기준점을 이용한 철도중심선형 좌표변환에 관한 연구)

  • Moon, Cheung-Kyun;Heo, Joon;Kang, Sang-Gu;Kim, Il-Joo;Park, Jae-Hong;Kim, Sung-Hoon
    • Journal of the Korean Society for Railway
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    • v.10 no.6
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    • pp.685-691
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    • 2007
  • In this paper through Honan high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21 cm to 40 cm diminishing to a gentle straight line, distortion of X axis varies 14 cm to 29 cm. Through a revision, the deviation value between the coordinates were 6 mm to 9 mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey (10 cm). consequently the coordinate conversion is possible using railroad control points as common control points.

Location Information Hiding Way Of HD Black Box Recording process (HD 블랙박스 녹화과정에서의 위치정보 은익방법)

  • Seok, Jin-Hwan;Yoon, Jong-Chul;Hong, Jong-Sung;Han, Chan-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.17 no.1
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    • pp.10-17
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    • 2016
  • GPS location information storage included in the HD black box is using a unique manner for each manufacturer does not have a specific standard. In this paper, in order to overcome the limitations of the storage space and thereby the image quality according to store GPS position information deteriorate to solve the problems that cause, we propose the location information concealment method included in the HDTV video content using a essential hidden region. HDTV video content is a Border Extender of 8 lines in the frame to the bottom of the compression will be required. This was inserted into the image of a gray scale used in block form in order to space the current position information is concealed to prevent image degradation. The proposed method was confirmed using real HD black box, there are more difficult to interpret the format of the ASCII code re-edit the location information when the compression effect disappears with the existing security zones added. Therefore, the proposed method is suitable for location-based services, such as Facebook or Youtube videos.

철도기준점을 이용한 철도중심선형 좌표변환에 관한연구 - 호남고속철도 계획노선을 중심으로 -

  • Moon, Cheung-Kyun;Heo, Joon;Kang, Sang-Du;Kim, Sang-Hoon
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1141-1151
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    • 2007
  • In this paper through Honam high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21cm to 40cm diminishing to a gentle straight line, distortion of X axis varies 14cm to 29cm. Through a revision, the deviation value between the coordinates were 6mm to 9mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey(10cm). consequently the coordinate conversion is possible using railroad control points as common control points.

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