• Title/Summary/Keyword: overlay analysis

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A Study of Disposition of Archaeological Remains in Wolseong Fortress of Gyeongju : Using Ground Penetration Radar(GPR) (GPR탐사를 통해 본 경주 월성의 유적 분포 현황 연구)

  • Oh, Hyun Dok;Shin, Jong Woo
    • Korean Journal of Heritage: History & Science
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    • v.43 no.3
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    • pp.306-333
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    • 2010
  • Previous studies on Wolseong fortress have focused on capital system of Silla Dynasty and on the recreation of Wolseong fortress due to the excavations in and around Wolseong moat. Since the report on the Geographical Survey of Wolseong fortress was published and GPR survey in Wolseong fortress was executed as a trial test in 2004, the academic interest in the site has now expanded to the inside of the fortress. From such context, the preliminary research on the fortress including geophysical survey had been commenced. GPR survey had been conducted for a year from March, 2007. The principal purpose of the recent 3D GPR survey was to provide visualization of subsurface images of the entire Wolseong fortress area. In order to obtain 3D GPR data, dense profile lines were laid in grid-form. The total area surveyed was $112,535m^2$. Depth slice was applied to analyse each level to examine how the layers of the remains had changed and overlapped over time. In addition, slice overlay analysis methodology was used to gather reflects of each depth on a single map. Isolated surface visualization, which is one of 3D analysis methods, was also employed to gain more in-depth understanding and more accurate interpretations of the remain The GPR survey has confirmed that there are building sites whose archaeological features can be classified into 14 different groups. Three interesting areas with huge public building arrangement have been found in Zone 2 in the far west, Zone 9 in the middle, and Zone 14 in the far east. It is recognized that such areas must had been used for important public functions. This research has displayed that 3D GPR survey can be effective for a vast area of archaeological remains and that slice overlay images can provide clearer image with high contrast for objects and remains buried the site.

Analysis of side-polished fiber couplers with an intermediate-coupling layer and improvement of their coupling efficiency (중간 결합층이 적층된 측면연마 광섬유 결합기의 해석 및 결합효율 개선)

  • 손경락;김광택
    • Korean Journal of Optics and Photonics
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    • v.15 no.1
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    • pp.28-33
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    • 2004
  • An in-line fiber coupler, based on side-polished single-mode fibers covered with an intermediate coupling layer and a planar waveguide, is analyzed by modeling the interaction region as an equivalent multi-layered planar waveguide. The reflectance for the multi-layered structure with and without buffer layer is illustrated as a function of the refractive index and thickness of the overlay waveguides. When the refractive index of the overlay waveguides is greater than that of the fiber core, the conditions for the intermediate coupling layer to increase the power coupling from the fiber to the overlays is also explained. Through the experimental results using a LiNbO$_3$planar waveguide, we show that the theoretical analysis is reasonable and in good agreement with the measured values.

Hydrosphere Change Detection of the Basin using Multi-temporal Landsat Satellite Imagery (다시기 Landsat영상을 이용한 유역의 수계 변화 탐지)

  • Kang, Joon-Mook;Park, Joon-Kyu;Um, Dae-Yong;Lee, Yong-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.31-39
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    • 2007
  • In this study, the hydrosphere change of the Daecheong dam basin was detected qualitatively and quantitatively using Landsat satellite images until recentness since the construction of Daecheong dam. The hydrosphere change of the basin was analyzed by applying supervised classification about Landsat satellite images which were classified according to the hydrosphere, vegetation, road and etc. for four distinct years which are 1981, 1987, 1993, and 2002 year. Landsat satellite images of each year were achieved overlay analysis with extracting only the hydrosphere, and though these results, the hydrosphere change of the Daecheong dam basin was monitored efficiently.

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Analysis of Overlay Accuracy in Digital Topographic Map and Cadastral Information Using Ortho Image map (정사투영 영상지도에 의한 수치지형도와 지적정보의 중첩정확도 분석)

  • Kang, Joon-Mook;Choi, Jong-Hyun;Kang, Young-Mi
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.57-68
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    • 1999
  • In case of topographic information construction it is most important as basemap determines the success or failure of GIS It is argument that digitizing works of basemap are divided by NGIS and PBLIS. So, it have to accompany the combination and application of cadastral information for constructing a usful basemap. In this study, we generated ortho image map using 1:5,000 aerial-photography image, present the comparative analysis for the overlay accuracy and map revision of topographic and cadastral information using ortho image map to base map. So, we present application schemes for land use, environment, and city planning field as well as union database by overlaying of image map and cadastral information.

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A Study on Extraction of the Topographical Parameters Using HEC-GEOHMS and DEM (HEC-GEOHMS와 DEM을 이용한 지형인자 추출에 관한 연구)

  • Lee, Jung-Min;Jeong, In-Ju;Kim, Sang-Yong
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.1 s.24
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    • pp.39-44
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    • 2003
  • Recently, GIS has been increasing its applicability in water resource field. The GIS based modeling process can generally be used for extracting channel network and watershed delineation. Through the overlay analysis, the extracted channel network can be overlayed with topographic and landuse maps to generate the input files for running a hydrologic model. This lead to consider GIS as a tool which can include subjective factors of the model designers in hydrologic analysis. Therefore, this study has compared GIS based HEC-GEOHMS with the classical approach. In general, both approaches have similar results, however, HEC-GROHMS has showed some errors. Based on the results, a GIS based approach could be more effective method with better credibility to obtain input parameters from topographic information as subsequent efforts were made to lessen the errors.

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Site Suitability Assessment for Joint Forest Management(JFM) - a Geospatial Approach

  • Jayakumar, S.;Ramachandran, A.;Bhaskaran, G.;Heo, Joon;Kim, Woo-Sun
    • Korean Journal of Remote Sensing
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    • v.23 no.5
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    • pp.473-481
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    • 2007
  • Joint Forest Management(JFM) is a concept of developing partnerships between fringe forest user groups and the Forest Department(FD) on the basis of mutual trust and jointly defined roles and responsibilities with regard to forest protection and development. In India, JFM was started during 1992 and it was implemented in many states. However success rate of JFM activity was not promising. Though there are many factors attributed to the failures, one of the main factors is the JFM site. This paper deals with the significant ground works to be done before planning for JFM using recent technologies such as remote sensing(RS) and Geographic Information System(GIS). Also it deals with the advantages of weighted overlay analysis in selecting suitable sites for JFM taking into consideration the various criteria. As a result of weighted overlay analysis, there were four types of suitability classes viz., less, moderate, highly and un-suitable. The moderately suitable class occupied maximum area(13209.64 ha) than less and highly suitable classes. If JFM is implemented on the suitability area, then the failure could be avoided in the future.

A Study on the Application of Fuzzy membership function in GIS Spatial Analysis - In the case of Evaluation of Waste Landfill - (GIS 공간분석에 있어 Fuzzy 함수의 적용에 관한 연구 -쓰레기 매립장 적지분석을 중심으로-)

  • Lim, Seung-Hyeon;Hwang, Ju-Tae;Park, Young-Ki;Lee, Jang-Choon
    • Journal of Korean Society for Geospatial Information Science
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    • v.15 no.2 s.40
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    • pp.43-49
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    • 2007
  • In this study, a GIS spatial analysis method adopted fuzzy concept was introduced and land suitability analysis of waste landfill were conducted through this method. Previous studies conducted site evaluation and land suitability analysis by appling spatial overlay of conventional GIS that based on the boolean logic of crisp set. However these method can not consider the uncertainty of spatial data and the incongruity of data classification criteria, because these method handle spatial data based on the boolean logic of crisp set. As not provided trustable analysis result, conventional GIS spatial overlay method lacks opportunity for expanding use in reality. This study selected waste landfill as facility for analysis and applied fuzzy spatial analysis method as an objective approach. In the concrete contents of study, a series process with regard to the definition procedure of membership function for continuous data and the fuzzy input value generation of spatial data for fuzzy analysis is established. As a result, in this study we proposed a method that derive parameters for deciding the membership function of spatial data by considering the criterion of data classification and factor selection for land suitability analysis of waste landfill.

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Performance Analysis of Operation Strategy of Dual Virtual Cell-based System under The Overlay Convergent Networks of Cognitive Networking (인지 네트워킹 기반 중첩 융합 네트워크에서 이중 가상 셀 운영방안의 성능분석)

  • Choi, Yu-Mi;Kim, Jeong-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.6B
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    • pp.483-488
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    • 2012
  • With the fast growing data traffic, the performance of the convergent overlay network environment under the cognitive networking environment is crucial for the implementation of the efficient network structure. In order to achieve high capacity and reliable link quality in wireless communication of the overlay convergent networks with the cognitive networking based on the advanced capability of the mobile terminal, a Distributed Wireless Communication System (DWCS) can provide the capability of ambient-aware dual cell system's operation. This paper has considered virtual cell: the Dual Virtual Cell (DVC), and also proposes DVC employment strategy based on DWCS network. One is the Active Virtual Cell which exists for user's actual data traffic and the other is the Candidate Virtual Cell which contains a set of candidate antennas to protect user's link quality from performance degradation or interruption. The considered system constructs DVC by using cognitive ability of finding useful virtual signals. Also, for multi-user high-rate data transmission, the DWCS system exploits Space-Time Trellis Codes. The effects of changing environments on the system performance has been investigated thereafter.

A Study on the Stereo Image Map Generation of Chuncheon Area using Satellite Overlay Images (위성영상을 이용한 춘천지역의 3차원 입체영상지도 생성에 관한 연구)

  • Yeon, Sang-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.3 no.4
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    • pp.1-10
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    • 2000
  • Satellite remote sensing images have much more information compared to a paper map. But these images are generally handled as particular image format gained from optical sensor, and must be processed and analyzed by computer with high priced digital image processing system. For the extraction of digital elevation model(DEM) from satellite image, we used the overlay image by SPOT-3 of Chuncheon area at the Kangwon province. According to the image condition, the precious geometric correction, the bundle adjustment for ortho-image generation and the stereo image mapping by several technical approaches were processed. So that we developed the methods of automatic DEM extraction and efficient stereo image map generation which can improve the digital image processing steps. Also, we applied the multiple direction birdeye view image for modeling and analysis using the remotely sensed overlay images with high resolution.

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Construction of an Exposure Risk Map and Spatial Knowledge Base for Asbestos in Korea (석면 공간지식베이스 구축을 통한 석면 노출위험도 작성)

  • Hwang, Jae-Hong;Lee, Byung-Joo
    • The Journal of Engineering Geology
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    • v.21 no.4
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    • pp.393-402
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    • 2011
  • Asbestos is a toxic material that can lead to lung cancer and other diseases. There is no information regarding areas in Korea that contain asbestos in nature; consequently we need to manage such areas with care. The purpose of this study was to construct a local graded map of asbestos exposure risk based on the natural occurrence of asbestos in rocks. We first developed a means of evaluating the asbestos exposure risk and produced thematic maps based on a field survey. In addition, we constructed a knowledge base for asbestos through analysis, representation and processes about asbestos data and prepare for the development of an evaluation model for asbestos exposure risk. The spatial analysis of asbestos exposure risk is based on a weighted-overlay analysis using expert opinion and the literature, and a fuzzy-overlay analysis using the uncertainty in the data. The map of asbestos exposure risk, compiled according to the weighted and fuzzy operations, is expected to be used to ensure safety and to reduce the risk of exposure to asbestos.