• Title/Summary/Keyword: Spatial database

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Quantitative Analysis of GIS-based Landslide Prediction Models Using Prediction Rate Curve (예측비율곡선을 이용한 GIS 기반 산사태 예측 모델의 정량적 비교)

  • 지광훈;박노욱;박노욱
    • Korean Journal of Remote Sensing
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    • v.17 no.3
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    • pp.199-210
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    • 2001
  • The purpose of this study is to compare the landslide prediction models quantitatively using prediction rate curve. A case study from the Jangheung area was used to illustrate the methodologies. The landslide locations were detected from remote sensing data and field survey, and geospatial information related to landslide occurrences were built as a spatial database in GIS. As prediction models, joint conditional probability model and certainty factor model were applied. For cross-validation approach, landslide locations were partitioned into two groups randomly. One group was used to construct prediction models, and the other group was used to validate prediction results. From the cross-validation analysis, it is possible to compare two models to each other in this study area. It is expected that these approaches will be used effectively to compare other prediction models and to analyze the causal factors in prediction models.

Application of Deegree of Open Source Middleware to Geo-Portal Implementation (지오 포털 구축을 위한 공개 소스 미들웨어 Deegree의 적용)

  • Park, Yong-Jae;Lee, Ki-Won
    • Korean Journal of Remote Sensing
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    • v.25 no.4
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    • pp.367-374
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    • 2009
  • Recently, new GIS applications such as gee portal and spatial data infrastructure are emerging. These are related to web computing techniques or methodologies based on web 2.0 paradigm, open API of portal, open source GIS, and international GIS standards which are independently on developing. The product of these applications can be realized in the linkage of those components. In this study, a case implementation concerning linkage with Google maps API and open source middleware named Deegree is carried out, and the results are discussed for open source uses in geo portal. Open source middleware supports various levels and types of OGC standards, so that it enables web publishing in the several web standard formats and data exchanges and interoperable uses between external database servers. Also the (unction extensions and the multi tier-based architecture within geo portal for specific purpose are possible.

Feasibility Mapping of Groundwater Yield Characteristics using Weight of Evidence Technique based on GIS in the Pocheon Area (GIS 기반 Weight of Evidence 기법을 이용한 포천 지역의 지하수 산출특성 예측도 작성)

  • Heo Seon-Hee;Lee Kiwon
    • Korean Journal of Remote Sensing
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    • v.21 no.6
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    • pp.493-503
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    • 2005
  • In this study, the weight of evidence(WofE) technique based on GIS was applied to spatially estimate the groundwater yield characteristics at the Pocheon area In Gyunggi-do. The groundwater preservation depends on many hydro-geologic factors that include hydrologic data, land-use data, topographic data, geological map and other natural materials collected at the site, even with man-made things. All these data can be digitally processed and managed by GIS database. In the applied technique of WofE, the prior probabilities were estimated as the factors that affect the yield on lineament, geology, drainage pattern or river system density, landuse and soil. We calculated the value of the weight values, W+ and W-, of each factor and estimated the contrast value of it. Results by the groundwater yield characteristic computation using this scheme were presented feasibility map in the form of the posterior probability to the consideration of in-situ samples. It is concluded that this technique is regarded as one of the effective techniques for the feasibility mapping related to the estimation of groundwater-bearing potential zones and its spatial pattern.

The Study on the Extraction of the Distribution Potential Area of Debris Landform Using Fuzzy Set and Bayesian Predictive Discriminate Model (퍼지집합과 베이지안 확률 기법을 이용한 암설사면지형 분포지역 추출에 관한 연구)

  • Wi, Nun-Sol;JANG, Dong-Ho
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.3
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    • pp.105-118
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    • 2017
  • The debris slope landforms which are existent in Korean mountains is generally on the steep slopes and mostly covered by vegetation, it is difficult to investigate the landform. Therefore a scientific method is required to come up with an effective field investigation plan. For this purpose, the use of Remote Sensing and GIS technologies for a spatial analysis is essential. This study has extracted the potential area of debrisslope landform formation using Fuzzy set and Bayesian Predictive Discriminate Model as mathematical data integration methods. The first step was to obtain information about debris locations and their related factors. This information was verified through field investigation and then used to build a database. In the second step, the map that zoning the study area based on the degree of debris formation possibility was generated using two modeling methods, and then cross validation technique was applied. In order to quantitatively analyze the accuracy of two modeling methods, the calculated potential rate of debrisformation within the study area was evaluated by plotting SRC(Success Rate Curve) and calculating AUC(Area Under the Curve). As a result, the prediction accuracy of Fuzzy set model wes 83.1% and Bayesian Predictive Discriminate Model wes 84.9%. It showed that two models are accurate and reliable and can contribute to efficient field investigation and debris landform management.

Simulation of Evacuation Route Scenarios Through Multicriteria Analysis for Rescue Activities

  • Castillo Osorio, Ever Enrique;Yoo, Hwan Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.5
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    • pp.303-313
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    • 2019
  • After a disaster happens in urban areas, many people need support for a quick evacuation. This work aims to develop a method for the calculation of the most feasible evacuation route inside buildings. In the methodology we simplify the geometry of the structural and non structural elements from the BIM (Building Information Modeling) to store them in a spatial database which follows standards to support vector data. Then, we apply the multicriteria analysis with the allocation of prioritization values and weight factors validated through the AHP (Analytic Hierarchy Process), in order to obtain the Importance Index S(n) of the elements. The criteria consider security conditions and distribution of the building's facilities. The S(n) is included as additional heuristic data for the calculation of the evacuation route through an algorithm developed as a variant of the $A^*$ pathfinding, The experimental results in the simulation of evacuation scenarios for vulnerable people in healthy physical conditions and for the elderly group, shown that the conditions about the wide of routes, restricted areas, vulnerable elements, floor roughness and location of facilities in the building applied in the multicriteria analysis has a high influence on the processing of the developed variant of $A^*$ algorithm. The criteria modify the evacuation route, because they considers as the most feasible route, the safest instead of the shortest, for the simulation of evacuation scenarios for people in healthy physical conditions. Likewise, they consider the route with the location of facilities for the movement of the elderly like the most feasible in the simulation of evacuation route for the transit of the elderly group. These results are important for the assessment of the decision makers to select between the shortest or safest route like the feasible for search and rescue activities.

Modeling flood and inundation in the lower ha thanh river system, Binh dinh province, vietnam

  • Don, N. Cao;Hang, N.T. Minh
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.195-195
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    • 2016
  • Kon - Ha Thanh River basin is the largest and the most important river basin in Binh Dinh, a province in the South Central Coast of Vietnam. In the lower rivers, frequent flooding and inundation caused by heavy rains, upstream flood and or uncontrolled flood released from upstream reservoirs, are very serious, causing damage to agriculture, socio-economic activity, human livelihood, property and lives. The damage is expected to increase in the future as a result of climate change. An advanced flood warning system could provide achievable non-structural measures for reducing such damages. In this study, we applied a modelling system which intergrates a 1-D river flow model and a 2-D surface flow model for simulating hydrodynamic flows in the river system and floodplain inundation. In the model, exchange of flows between the river and surface floodplain is calculated through established links, which determine the overflow from river nodes to surface grids or vice versa. These occur due to overtopping or failure of the levee when water height surpasses levee height. A GIS based comprehensive raster database of different spatial data layers was prepared and used in the model that incorporated detailed information about urban terrain features like embankments, roads, bridges, culverts, etc. in the simulation. The model calibration and validation were made using observed data in some gauging stations and flood extents in the floodplain. This research serves as an example how advanced modelling combined with GIS data can be used to support the development of efficient strategies for flood emergency and evacuation but also for designing flood mitigation measures.

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Rotated Face Detection Using Polar Coordinate Transform and AdaBoost (극좌표계 변환과 AdaBoost를 이용한 회전 얼굴 검출)

  • Jang, Kyung-Shik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.7
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    • pp.896-902
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    • 2021
  • Rotated face detection is required in many applications but still remains as a challenging task, due to the large variations of face appearances. In this paper, a polar coordinate transform that is not affected by rotation is proposed. In addition, a method for effectively detecting rotated faces using the transformed image has been proposed. The proposed polar coordinate transform maintains spatial information between facial components such as eyes, mouth, etc., since the positions of facial components are always maintained regardless of rotation angle, thereby eliminating rotation effects. Polar coordinate transformed images are trained using AdaBoost, which is used for frontal face detection, and rotated faces are detected. We validate the detected faces using LBP that trained the non-face images. Experiments on 3600 face images obtained by rotating images in the BioID database show a rotating face detection rate of 96.17%. Furthermore, we accurately detected rotated faces in images with a background containing multiple rotated faces.

Performance Evaluation of Rainfall Disaggregation according to Temporal Scale of Rainfall Data (강우자료의 시간해상도에 따른 강우 분해 성능 평가)

  • Lee, Jeonghoon;Jang, Juhyoung;Kim, Sangdan
    • Journal of Wetlands Research
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    • v.20 no.4
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    • pp.345-352
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    • 2018
  • In this study, rainfall data with various temporal scales (3-, 6-, 12-, 24-hr) are disaggregated into 1-hourly rainfall data to evaluate the performance of rainfall disaggregation technique. The rainfall disaggregation technique is based on a database generated by the stochastic point rainfall model, the Neyman-Scott Rectangular Pulse Model (NSRPM). Performance evaluation is carried out using July rainfall data of Ulsan, Changwon, Busan and Milyang weather stations in Korea. As a result, the rainfall disaggregation technique showed excellent performance that can consider not only the major statistics of rainfall but also the spatial correlation. It also indirectly shows the uncertainty of future climate change scenarios with daily temporal scale. The rainfall disaggregation technique is expected to disaggregate the future climate change scenarios, and to be effective in the future watershed management.

Estimating Length of Jeju Batdam Using Cadastral Information (지적 정보를 이용한 제주 밭담 길이 추정)

  • Park, Jong-Jun;Kwon, Yoon-Ku
    • Journal of Korean Society of Rural Planning
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    • v.25 no.3
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    • pp.37-44
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    • 2019
  • The value of Jeju Batdam has been reexamined as it is listed as a nationally important agricultural heritage and globally important agricultural heritage systems. However, it is already exposed to threats such as reduction of agricultural population and cultivation area. Despite efforts like the agricultural heritage system to preserve traditional agriculture, there is few basic investigation into the current status of Jeju Batdam. The purpose of this study is to estimate the length of Jeju Batdam. We used the continuous cadastral map of Jeju area to extract the boundaries of the field lot. In the cadastral map, the farmland was selected by selecting dry fields, paddy fields and orchards. 300 sample site were selected from the extracted farmland, and the boundaries between the Internet map and the parcels were superimposed and the differences were confirmed on the drawing. After that, field survey was conducted to confirm the boundary of the parcels and the existence of actual Batdam. It is estimated that the length estimated from this study is at least 23,983km and maximum 142,353km, which is at least 1,830km longer than 22,108km announced in 2007. Since Jeju Batdam is based on land parcel boundary, it is an objective and efficient method to utilize intellectual information. In addition, because it is subordinate to farmland, new information can be extracted reflecting the change of land use and make the spatial database based on the cadastral maps.

Design of The RESTful Heterogeneous Data Service Architecture for Korean e-Navigation Operation System (e-Navigation 운영시스템을 위한 RESTful 이종 데이터 서비스 시스템 아키텍처 설계)

  • Jang, Wonseok;Lee, Woojin
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.1
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    • pp.49-57
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    • 2019
  • The International Maritime Organization is developing a maritime safety system called eNavigation in order to effectively respond to accidents occurring on board vessels. Korea is actively participating in the development of eNavigation and is developing Korean eNavigation by adding its own concept to eNavigation of the IMO. eNavigation is designed to provide various functions for marine safety. The data required for each function is various such as spatial data, relational data, file, weather grid. Therefore, there is a need for a system that can appropriately provide heterogeneous data suitable for eNavigation to each eNavigation's service system. In this paper, we analyzed the kinds of data needed for e-Navigation and designed the architecture of heterogeneous data service system that could provide these data properly.