• 제목/요약/키워드: Geographic difference

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육.해도 통합수치도 제작 기술 개발과 응용 방안 (A Study on the Technology Development and Application Plan for Making an Integrated Digital Map of an Electronical Navigational Chart and a Digital Terrain Map)

  • 이기철;박창호;서상현;김정희;정희균
    • 한국항만학회지
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    • 제14권2호
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    • pp.209-217
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    • 2000
  • This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coastal area.

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Ionospheric Storm and Spatial Gradient Analysis for GBAS

  • Kim, Jeong-Rae;Yang, Tae-Hyoung;Lee, Young-Jae;Jun, Hyang-Sig;Nam, Gi-Wook
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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    • pp.361-365
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    • 2006
  • High ionospheric spatial gradient during ionospheric storm is most concern for the landing approach with GNSS (Global Navigation Satellite System) augmentation systems. In case of the GBAS (Ground-Based Augmentation System), the ionospheric storm causes sudden increase of the ionospheric delay difference between a ground facility and a user (aircraft), and the aircraft position error increases significantly. Since the ionosphere behavior and the storm effect depend on geographic location, understanding the ionospheric storm behavior at specific regional area is crucial for the GNSS augmentation system development and implementation. Korea Aerospace Research Institute and collaborating universities have been developing an integrity monitoring test bed for GBAS research and for future regional augmentation system development. By using the dense GPS (Global Positioning System) networks in Korea, a regional ionosphere map is constructed for finding detailed aspect of the ionosphere variation. Preliminary analysis on the ionospheric gradient variation during a recent storm period is performed and the results are discussed.

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토폴로지 구축을 통한 측정 오차 보정 기반의 위치인식 기법 (Localization algorithm by using location error compensation through topology constructions)

  • 유진호;권영구
    • 한국정보통신학회논문지
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    • 제18권9호
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    • pp.2243-2250
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    • 2014
  • 무선센서 네트워크에서, 위치기반의 라우팅 알고리즘은 네트워크의 성능을 향상 시킬 수 있다. 따라서 많은 위치 추적 알고리즘이 제안되고 있다. 하지만, 실제 상황의 무선센서 네트워크에서 각각의 노드가 자신의 위치를 인지할 시 오차가 수반된다. 특히 실내 환경은 콘크리트 벽이나 가구와 같은 NLOS환경을 만드는 장해물을 가지고 있기 때문에 위치 추적 시 심각한 오차가 발생한다. 이러한 문제를 해결하기 위해서, 앵커노드로부터 얻어지는 위치정보로 구축한 토폴로지와 모바일 노드간의 연결을 가중치로 하는 MST 토폴로지 정보의 차이점을 이용해서 위치 오차를 보정하는 알고리즘을 제안한다. 제안한 알고리즘은 NLOS환경이 존재하는 네트워크에서, 위치 오차를 보정하여 위치기반 네트워크의 성능을 개선할 수 있다.

육.해도 통합수치도 제작 기술 개발과 응용 방안+ (A Study on the Technology Development and Application Plan for making an Integrated Digital Map of an Electronical Navigational Chart and a Digital Terrain Map)

  • 이기철;정희균;박창호;서상현;김정희
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 1999년도 추계학술대회논문집
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    • pp.347-356
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    • 1999
  • This study is to develop the technology and the ways of the practical use of the integrated digital map of and Electronical Navigational Chart(ENC) and Digital Terrain Map(DTM) for the effective and scientific based conservation, development and management. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined and the characteristics of digital maps developed by Korean Geography Institute and National Marine Investigation Institute are carefully analyzed. A test coastal map was developed based on the integrated digital map, a high resolution satellite image and Global Positioning System. Results from the edge matching analysis of coastal lines shows 8 meters difference in maximum. The problems, causes and solutions for the edge matched differences are described. Furthermore, the practical value of utilization, future use and various field of application are described based on the integrated digital map data base of coast area.

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Monitoring of Graveyards in Mountainous Areas with Simulated KOMPSAT-2 imagery

  • Chang, Eun-Mi;Kim, Min-Ho;Lee, Byung-Whan;Heo, Min
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1409-1411
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    • 2003
  • The application of simulated KOMPSAT-2 imagery to monitor graveyards is to be developed. Positions calculated from image were compared with those obtained from Geographic Positioning System. With 24 checkpoints, the position of graveyards showed within 5-meter range. Unsupervised classification, supervised classification, and objected-orientation classification algorithms were used to extract the graveyard. Unsupervised classification with masking processes based on National topographic data gives the best result. The graveyards were categorized with four types in field studies while the two types of graveyards were shown in descriptive statistics. Cluster Analysis and discriminant analysis showed the consistency with two types of tombs. It was hard to get a specific spectral signature of graveyards, as they are covered with grasses at different levels and shaded from the surrounding trees. The slopes and aspects of location of graveyards did not make any difference in the spectral signatures. This study gives the basic spectral characteristics for further development of objected-oriented classification algorithms and plausibility of KOMPSAT-2 images for management of mountainous areas in the aspect of position accuracy and classification accuracy.

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Urban Quality of Life Assessment Using Satellite Image and Socioeconomic Data in GIS

  • Jun, Byong-Woon
    • 대한원격탐사학회지
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    • 제22권5호
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    • pp.325-335
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    • 2006
  • This paper evaluates and maps the quality of life in the Atlanta, Georgia metropolitan area in 2000. Three environmental variables from Landsat TM data, four socioeconomic variables from census data, and a hazard-related variable from toxic release inventory (TRI) database were integrated into a geographic information system (GIS) environment for the quality of life assessment. To solve the incompatibility problem in areal units among different data, the four socioeconomic variables aggregated by zonal units were spatially disaggregated into individual pixels. Principal components analysis (PCA) was employed to integrate and transform environmental, socioeconomic, and hazard-related variables into a resultant quality of life score for each pixel. Results indicate that the highest quality of life score was found around Sandy Springs, Roswell, Alphretta, and the northern parts of Fulton County along Georgia 400 whereas the lowest quality of life score was clustered around Smyma of Cobb County, the inner city of Atlanta, and Hartsfield-Jackson International Airport. The results also reveals that normalized difference vegetation index (NDVI) and relative risk from TRI facilities are two versatile indicators of environmental and socioeconomic quality of an urban area in the United States.

A Satellite View of Urban Heat Island: Causative Factors and Scenario Analysis

  • Wong, Man Sing;Nichol, Janet;Lee, Kwon-Ho
    • 대한원격탐사학회지
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    • 제26권6호
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    • pp.617-627
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    • 2010
  • Although many researches for heat island study have been developed, there is little attempt to link the findings to actual and hypothetical scenarios of urban developments which would help to mitigate the Urban Heat Island (UHI) in cities. The aim of this paper is to analyze the UHI at urban area with different geometries, land use, and environmental factors, and emphasis on the influence of different geometric and environmental parameters on ambient air temperature. In order to evaluate these effects, the parameters of (i) Air pollution (i.e. Aerosol Optical Thickness (AOT)), (ii) Green space Normalized Difference Vegetation Index (NDVI), (iii) Anthropogenic heat (AH) (iv) Building density (BD), (v) Building height (BH), and (vi) Air temperature (Ta) were mapped. The optimum operational scales between Heat Island Intensity (HII) and above parameters were evaluated by testing the strength of the correlations for every resolution. The best compromised scale for all parameters is 275m resolution. Thus, the measurements of these parameters contributing to heat island formation over the study areas of Hong Kong were established from mathematical relationships between them and in combination at 275m resolution. The mathematical models were then tabulated to show the impact of different percentages of parameters on HII. These tables are useful to predict the probable climatic implications of future planning decisions.

A Comparative Study of Algorithms for Estimating Land Surface Temperature from MODIS Data

  • Suh, Myoung-Seok;Kim, So-Hee;Kang, Jeon-Ho
    • 대한원격탐사학회지
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    • 제24권1호
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    • pp.65-78
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    • 2008
  • This study compares the relative accuracy and consistency of four split-window land surface temperature (LST) algorithms (Becker and Li, Kerr et ai., Price, Ulivieri et al.) using 24 sets of Terra (Aqua)/Moderate Resolution Imaging Spectroradiometer (MODIS) data, observed ground grass temperature and air temperature over South Korea. The effective spectral emissivities of two thermal infrared bands have been retrieved by vegetation coverage method using the normalized difference vegetation index. The intercomparison results among the four LST algorithms show that the three algorithms (Becker-Li, Price, and Ulivieri et al.) show very similar performances. The LST estimated by the Becker and Li's algorithm is the highest, whereas that by the Kerr et al.'s algorithm is the lowest without regard to the geographic locations and seasons. The performance of four LST algorithms is significantly better during cold season (night) than warm season (day). And the LST derived from Terra/MODIS is closer to the observed LST than that of Aqua/MODIS. In general, the performances of Becker-Li and Ulivieri et al algorithms are systematically better than the others without regard to the day/night, seasons, and satellites. And the root mean square error and bias of Ulivieri et al. algorithm are consistently less than that of Becker-Li for the four seasons.

Genetic Distances Within-Population and Between-Population of Tonguesole, Cynoglossus spp. Identified by PCR Technique

  • Yoon, Jong-Man
    • 한국발생생물학회지:발생과생식
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    • 제23권3호
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    • pp.297-304
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    • 2019
  • The higher fragment sizes (>2,100 bp) are not observed in the two C. spp. populations. The six oligonucleotides primers OPA-11, OPB-09, OPB-14, OPB-20, OPC-14, and OPC-18 were used to generate the unique shared loci to each tonguesole population and shared loci by the two tonguesole populations. The hierarchical polar dendrogram indicates two main clusters: Gunsan (GUNSAN 01-GUNSAN 11) and the Atlantic (ATLANTIC 12-ATLANTIC 22) from two geographic populations of tonguesoles. The shortest genetic distance displaying significant molecular difference was between individuals' GUNSAN no. 02-GUNSAN no. 01 (genetic distance=0.038). In the long run, individual no. 02 of the ATLANTIC tonguesole was most distantly related to GUNSAN no. 06 (genetic distance=0.958). These results demonstrate that the Gunsan tonguesole population is genetically different from the Atlantic tonguesole population. The potential of PCR analysis to identify diagnostic markers for the identification of two tonguesole populations has been demonstrated. As a rule, using various oligonucleotides primers, this PCR method has been applied to identify polymorphic/specific markers particular to species and geographical population, as well as genetic diversity/polymorphism in diverse species of organisms.

Impact of Multi-GNSS Measurements on Baseline Processing for Control Surveying Applications

  • Pawar, Komal Narayan;Yun, Seonghyeon;Lee, Hungkyu;Nguyen, Dinh Huy
    • Journal of Positioning, Navigation, and Timing
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    • 제10권2호
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    • pp.103-111
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    • 2021
  • A series of experiments have been carried out by using National Geographic Information Institute(NGII)'s Continuously Operating Reference Station (CORS) data with various strategies to analyze the impact of multi-GNSS measurements on baseline processing. The results of baseline processing were compared in terms of ambiguity fixing rate, precision, and hypothesis tests were conducted to confirm the statistical difference. The combination of multi-GNSS measurements has helped to improve ambiguity fixing rate, especially under harsh positioning environments. Combination of GPS, Galileo, BeiDou could get better precision than that of GPS, GLONASS, Galileo, and adding QZSS made the baseline solution's vertical component more precisely. The hypothesis tests have statistically confirmed that the inclusion of the multi-GNSS in the baseline processing enables not only to reduce field observation time length but also to enhance the solution's precision. However, it is of interest to notice that results of the baseline solution are dependent upon the software used. Hence, comprehensive studies should be performed shortly to derive the best practice to select the appropriate software.