• Title/Summary/Keyword: Environmental Spatial Information

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Improved Estimation of Hourly Surface Ozone Concentrations using Stacking Ensemble-based Spatial Interpolation (스태킹 앙상블 모델을 이용한 시간별 지상 오존 공간내삽 정확도 향상)

  • KIM, Ye-Jin;KANG, Eun-Jin;CHO, Dong-Jin;LEE, Si-Woo;IM, Jung-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.3
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    • pp.74-99
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    • 2022
  • Surface ozone is produced by photochemical reactions of nitrogen oxides(NOx) and volatile organic compounds(VOCs) emitted from vehicles and industrial sites, adversely affecting vegetation and the human body. In South Korea, ozone is monitored in real-time at stations(i.e., point measurements), but it is difficult to monitor and analyze its continuous spatial distribution. In this study, surface ozone concentrations were interpolated to have a spatial resolution of 1.5km every hour using the stacking ensemble technique, followed by a 5-fold cross-validation. Base models for the stacking ensemble were cokriging, multi-linear regression(MLR), random forest(RF), and support vector regression(SVR), while MLR was used as the meta model, having all base model results as additional input variables. The results showed that the stacking ensemble model yielded the better performance than the individual base models, resulting in an averaged R of 0.76 and RMSE of 0.0065ppm during the study period of 2020. The surface ozone concentration distribution generated by the stacking ensemble model had a wider range with a spatial pattern similar with terrain and urbanization variables, compared to those by the base models. Not only should the proposed model be capable of producing the hourly spatial distribution of ozone, but it should also be highly applicable for calculating the daily maximum 8-hour ozone concentrations.

Image Fusion Methods for Multispectral and Panchromatic Images of Pleiades and KOMPSAT 3 Satellites

  • Kim, Yeji;Choi, Jaewan;Kim, Yongil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.5
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    • pp.413-422
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    • 2018
  • Many applications using satellite data from high-resolution multispectral sensors require an image fusion step, known as pansharpening, before processing and analyzing the multispectral images when spatial fidelity is crucial. Image fusion methods are to improve images with higher spatial and spectral resolutions by reducing spectral distortion, which occurs on image fusion processing. The image fusion methods can be classified into MRA (Multi-Resolution Analysis) and CSA (Component Substitution Analysis) approaches. To suggest the efficient image fusion method for Pleiades and KOMPSAT (Korea Multi-Purpose Satellite) 3 satellites, this study will evaluate image fusion methods for multispectral and panchromatic images. HPF (High-Pass Filtering), SFIM (Smoothing Filter-based Intensity Modulation), GS (Gram Schmidt), and GSA (Adoptive GS) were selected for MRA and CSA based image fusion methods and applied on multispectral and panchromatic images. Their performances were evaluated using visual and quality index analysis. HPF and SFIM fusion results presented low performance of spatial details. GS and GSA fusion results had enhanced spatial information closer to panchromatic images, but GS produced more spectral distortions on urban structures. This study presented that GSA was effective to improve spatial resolution of multispectral images from Pleiades 1A and KOMPSAT 3.

4S Framework Construction Structure for Interoperability of Spatial Information (공간 정보의 상호운용성을 위한 4S 기반 프레임워크 구축)

  • Oh, Byoung-Woo;Kim, Min-Soo;Joo, In-Hak;Lee, Jong-Hun;Yang, Young-Kyu
    • Journal of Korea Spatial Information System Society
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    • v.3 no.1 s.5
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    • pp.95-108
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    • 2001
  • The provision of spatial data is a key infrastructural requirement for the promotion of economic growth, environmental quality, social progress, etc. 4S technology integrates 4 kinds of systems that process spatial data: GIS (Geographic Information System), GNSS (Global Navigation Satellite System), ITS (Intelligent Transport System), and SIIS (Spatial Imagery Information System). Spatial data processing field is expected to get synergy effect and overcomes development limit of individual unit technology via 4S technology. This paper discusses both the development of 4S-kernel technology and the construction of 4S-based framework, In the development of 4S kernel technology, we will concentrate on the following issues: the development of 4S base components for reciprocity integration among GIS, SIIS, GNSS and ITS technologies, the development of 4S-Mobile S/W and H/W, 4S-Van components, and national LBS technologies. And in the construction of 4S-based framework, we will especially concentrate on the ISP for overall 4S technologies, the international cooperative research center, and the guide model deduction for supervision and certification of 4S projects. Finally, we examine about how the construction of 4S-baed framework affects 4S industry.

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X3D Based Web Visualization by Data Fusion of 3D Spatial Information and Video Sequence (3D 공간정보와 비디오 융합에 의한 X3D기반 웹 가시화)

  • Sohn, Hong-Gyoo;Kim, Seong-Sam;Yoo, Byoung-Hyun;Kim, Sang-Min
    • Journal of Korean Society for Geospatial Information Science
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    • v.17 no.4
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    • pp.95-103
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    • 2009
  • Global interests for construction of 3 dimensional spatial information has risen due to development of measurement sensors and data processing technologies. In spite of criticism for the violation of personal privacy, CCTV cameras equipped in outdoor public space of urban area are used as a fundamental sensor for traffic management, crime prevention or hazard monitoring. For safety guarantee in urban environment and disaster prevention, a surveillance system integrating pre-constructed 3 dimensional spatial information with CCTV data or video sequence is needed for monitoring and observing emergent situation interactively in real time. In this study, we proposed applicability of the prototype system for web visualization based on X3D, an international standard of real time web visualization, by integrating 3 dimensional spatial information with video sequence.

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A Study on Optimal Shape-Size Index Extraction for Classification of High Resolution Satellite Imagery (고해상도 영상의 분류결과 개선을 위한 최적의 Shape-Size Index 추출에 관한 연구)

  • Han, You-Kyung;Kim, Hye-Jin;Choi, Jae-Wan;Kim, Yong-Il
    • Korean Journal of Remote Sensing
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    • v.25 no.2
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    • pp.145-154
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    • 2009
  • High spatial resolution satellite image classification has a limitation when only using the spectral information due to the complex spatial arrangement of features and spectral heterogeneity within each class. Therefore, the extraction of the spatial information is one of the most important steps in high resolution satellite image classification. This study proposes a new spatial feature extraction method, named SSI(Shape-Size Index). SSI uses a simple region-growing based image segmentation and allocates spatial property value in each segment. The extracted feature is integrated with spectral bands to improve overall classification accuracy. The classification is achieved by applying a SVM(Support Vector Machines) classifier. In order to evaluate the proposed feature extraction method, KOMPSAT-2 and QuickBird-2 data are used for experiments. It is demonstrated that proposed SSI algorithm leads to a notable increase in classification accuracy.

Variogram Analysis for Spatial Similarity Measures : A Case Study using Geochemical Data Sets in the Taebaek Area (공간적 상관도 측정을 위한 변이도 분석 : 태백지역의 지화학자료를 이용한 사례 연구)

  • Lee, Kiwon;Kwon, Byung-Doo
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.271-277
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    • 1995
  • The geological information analysis based on spatial statistical techniques have been studied in relation to mineral exploration. The applicability of outlier detection using moving-window statistics and directional cross-variography analysis have been verified by using geochemical data sets surveyed in the Taebaek area for mineral exploration. The directional variogram analysis has been basically known as a geostatistical method for spatial continuity measures. In this study, the application of this proposed method was extended to measure spatial correlation or similarity problems between two geochemical elements. For the appraisal of the usefulness of this scheme, five kinds of variogram functions were computed for original data and revised data, obtained by removing outliers detected by moving-window statistics and the results were compared. It is concluded that these advanced spatial statistical methods at the interpretation stage of spatial similarity provide us with valuable quantitative results as decision-supporting information for regional mineral exploration task.

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Smart geophysical characterization of particulate materials in a laboratory

  • Kwon, Tae-Hyuk;Cho, Gye-Chun
    • Smart Structures and Systems
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    • v.1 no.2
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    • pp.217-233
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    • 2005
  • Elastic and electromagnetic waves can be used to gather important information about particulate materials. To facilitate smart geophysical characterization of particulate materials, their fundamental properties are discussed and experimental procedures are presented for both elastic and electromagnetic waves. The first application is related to the characterization of particulate materials using shear waves, concentrating on changes in effective stress during consolidation, multi-phase phenomena with relation to capillarity, and microscale characteristics of particles. The second application involves electromagnetic waves, focusing on stratigraphy detection in layered soils, estimation of void ratio and its spatial distribution, and conduction in unsaturated soils. Experimental results suggest that shear waves allow studying particle contact phenomena and the evolution of interparticle forces, while electromagnetic waves give insight into the characteristics of the fluid phase and its spatial distribution.

Consideration of human disturbance to enhance avian species richness in urban ecosystem (도시생태계 내 조류 종풍부도 증진을 위한 인간영향 및 교란가능성의 반영)

  • Kim, Yoon-Jung
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.5
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    • pp.25-34
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    • 2021
  • Increase in avian species richness is one of the important issues of urban biodiversity policies, since it can promote diverse ecosystem services such as seed dispersal, education, and pollination. However, though human disturbance can significantly affect avian species richness, there are limited studies on the way to reflect the dynamics of floating population. Therefore, this study analyzed the spatial relationship between avian species richness, floating population, and vegetation cover using telecommunications information to identify the areas that requiring targeted monitoring and restoration action. Bivariate Local Moran's I was applied to identify LISA cluster map that showing representative biotopes, which reflect significant spatial relationship between species richness and population distribution. Edge density and distribution of ndvi were identified for evaluating relative adequacy of selected biotopes to strengthen the robust biodiversity network. This study offers insight to consider human disturbance in spatial context using innovative big data to increase the effectiveness of urban biodiversity measures.

A study on the integration and linkage of basic information within National Territorial planning system (국토계획체계내 기초정보 통합 및 연계화 방안)

  • 김정훈;채미옥
    • Spatial Information Research
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    • v.11 no.4
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    • pp.465-480
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    • 2003
  • Various basic information is required to scientifically and rationally utilize and manage national territory. For this, a variety of informatization projects have on developed from public sectors. However, there are a lot of problems including weak linkage between individual information systems and databases and lack of the coordinating function in promoting national territorial informatization projects. This study aims to provide policy alternatives on the integration and linkage of basic information within national territorial planning system. These results will be applied to the planned utilization and environmental friendly management of national territory.

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