• 대한원격탐사학회지
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• 제37권5_1호
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• pp.1149-1161
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• 2021

컴퓨터 비전 기술이 위성영상에 적용되면서, 최근 들어 딥러닝 영상인식을 이용한 구름 탐지가 관심을 끌고 있다. 본연구에서는 SPARCS (Spatial Procedures for Automated Removal of Cloud and Shadow) Cloud Dataset과 영상자료증대 기법을 활용하여 U-Net 구름탐지 모델링을 수행하고, 10폴드 교차검증을 통해 객관적인 정확도 평가를 수행하였다. 512×512 화소로 구성된 1800장의 학습자료에 대한 암맹평가 결과, Accuracy 0.821, Precision 0.847, Recall 0.821, F1-score 0.831, IoU (Intersection over Union) 0.723의 비교적 높은 정확도를 나타냈다. 그러나 구름그림자 중 14.5%, 구름 중 19.7% 정도가 땅으로 잘못 예측되기도 했는데, 이는 학습자료의 양과 질을 보다 더 향상시킴으로써 개선 가능할 것으로 보인다. 또한 최근 각광받고 있는 DeepLab V3+ 모델이나 NAS(Neural Architecture Search) 최적화 기법을 통해 차세대중형위성 1, 2, 4호 등의 구름탐지에 활용 가능할 것으로 기대한다.

• 한국환경보건학회지
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• 제38권5호
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• pp.369-379
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• 2012

Objectives: Spatial analysis is useful for understanding complicated causal relationships. This paper focuses trends and appling methods for spatial analysis associated with environmental asbestos exposure. Methods: Literature review and reflection of experience of authors were conducted to know academic background of spatial analysis, appling methods on epidemiology and asbestos exposure. Results: Spatial analysis based on spatial autocorrelation provides a variety of methods through which to conduct mapping, cluster analysis, diffusion, interpolation, and identification. Cause of disease occurrence can be investigated through spatial analysis. Appropriate methods can be applied according to contagiousness and continuity. Spatial analysis for asbestos exposure source is needed to study asbestos related diseases. Although a great amount of research has used spatial analysis to study exposure assessment and distribution of disease occurrence, these studies tend to focus on the construction of a thematic map without different forms of analysis. Recently, spatial analysis has been advanced by merging with web tools, mobile computing, statistical packages, social network analysis, and big data. Conclusions: Because the trend in spatial analysis has evolved from simple marking into a variety of forms of analyses, environmental researchers including asbestos exposure study are required to be aware of recent trends.

• 한국측량학회지
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• 제33권5호
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• pp.373-383
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• 2015

공간정보는 국토의 효율적 관리와 재해·재난·환경·시설물·기업마케팅·문화재 관리 등 사회전반에 걸쳐 활용되고 있으며, 향후 더 많은 수요가 예상되고 있다. 이에 중앙정부, 지방자치단체, 공공기관 등에서는 데이터 품질이 확보된 정확한 정보를 기반으로 국가공간정보시스템(국토교통부 국토정보정책관실에서 관리하는 15개의 공간정보 관련 시스템) 체계를 구축해야하며, 이를 통해 정책결정이나 민원지원에서 공간정보의 활용과 편의를 도모할 수 있다. 그러나, 현재 국가공간정보시스템은 개별 업무처리 위주로 시스템을 구축하고, 분산된 연계 채널로 인해 데이터 중복구축과 품질 저하라는 문제가 발생하여 공간정보의 공개·개방이 소극적으로 이루어지고 있는 상황이다. 본 연구에서는 국가공간정보시스템의 데이터 흐름에 가치사슬 모형을 적용하여 ‘생산·구축’, ‘통합·공유’, ‘응용·융복합’, ‘공개·개방’ 이라는 4단계의 공간정보 데이터 흐름 기준을 도출하였으며, 이를 기반으로 15개의 국가공간정보시스템에 대한 현황분석을 통해 시사점을 도출하고 국가공간정보시스템 개편 추진 방향을 제시하였다. 향후 국가공간 정보시스템의 개편 모델과 순환체계를 통해 최신성·일관성·정확성·연계성이 확보된 공간정보서비스를 제공하여 수요자의 요구를 만족시키고 공공활용 및 민간개방 활성화를 기대한다.

• 대한공간정보학회지
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• 제24권2호
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• pp.63-70
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• 2016

A housing market in an urban area is not just a single market but a combination of regionally different submarkets. This study begins with a critical mind that previous researches did not consider the spatial autocorrelation of each area where the housings are located. The clustering analysis of housing submarket which considers spatial autocorrelation is performed as it follows. First, 4 housing market attribute variables are reducted to 1 variable by principle component analysis. Then, after calculating $Gi^*max$ by AMOEBA, 7 housing submarkets which have similar characteristics based on $Gi^*max$ are classified. The characteristics of each submarket are investigated, then political implication is deduced as the following. Different level of housing policy should be made to each cluster because each cluster has different level of spatial autocorrelation.

• 한국측량학회지
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• 제34권2호
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• pp.111-120
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• 2016

Prior knowledge about the SNS (Social Network Services) datasets is often required to conduct valuable analysis using social media data. Understanding the characteristics of the information extracted from SNS datasets leaves much to be desired in many ways. This paper purposes on analyzing the detail of the target social network services, Twitter, Instagram, and YouTube to establish the spatial informatization process to integrate social media information with existing spatial datasets. In this study, valuable information in SNS datasets have been selected and total 12,938 data have been collected in Seoul via Open API. The dataset has been geo-coded and turned into the point form. We also removed the overlapped values of the dataset to conduct spatial integration with the existing building layers. The resultant of this spatial integration process will be utilized in various industries and become a fundamental resource to further studies related to geospatial integration using social media datasets.

• 한국측량학회지
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• 제34권2호
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• pp.185-194
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• 2016

The purpose of this study is to present a method to provide environment information based on spatial information document. At present, a lot of spatial information, including environment information, is being produced, but separate software or system is required for the user to acquire the information. In particular, in the case of environment information, various types of information are being produced, such as ecology, vegetation and measurement network data. Therefore, it is necessary to present the form and the making method of spatial information document that allows using environment information as spatial information without separate software or system. To provide spatial information document-based environment information, types and forms of environment information, data format and offering methods produced by the government, in particular, the Ministry of Environment and the local governments, are analyzed. 12 fields are classified and the form of produced data is GIS DB, measurement network data, text data and so on. With decrease of paper maps, spatial information document that offers display by layer, coordinate data, attribute data, distance and area measurement, location search by coordinates, GPS location linkage and location display on the map is presented to increase utilization of geo-environment information maps. Finally, the standard document specification based on spatial information document is presented in consideration of usability and readability in order to provide a variety of environment information without separate software or system.

• 대한원격탐사학회지
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• 제36권1호
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• pp.41-53
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• 2020

The production of near- and off-shore fisheries in South Korea is decreasing due to rapid changes in the fishing environment, particularly including higher sea temperature in recent years. To improve the competitiveness of the fisheries, it is necessary to provide fish catch information that changes spatiotemporally according to the sea state. In this study, artificial intelligence models that predict the CPUE (catch per unit effort) of mackerel, anchovies, and squid (Todarodes pacificus), which are three major fish species in the near- and off-shore areas of South Korea, on a 15-km grid and daily basis were developed. The models were trained and validated using the sea surface temperature, rainfall, relative humidity, pressure,sea surface wind velocity, significant wave height, and salinity as input data, and the fish catch statistics of Suhyup (National Federation of Fisheries Cooperatives) as observed data. The 10-fold blind test results showed that the developed artificial intelligence models exhibited accuracy with a corresponding correlation coefficient of 0.86. It is expected that the fish catch models can be actually operated with high accuracy under various sea conditions if high-quality large-volume data are available.

• 대한공간정보학회지
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• 제18권1호
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• pp.47-53
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• 2010

정확한 하천유량은 하천이 지니고 있는 이수, 치수 및 생태기능이 원활이 유지되기 위해서 가장 중요한 항목이다. 특히 하천의 생태기능은 하천의 환경개선에 있어 매우 중요한 기능이다. 하천의 생태유량에 있어서 하천에 서식하는 생물 및 하천지형에 대한 정확한 정보는 중요한 역할을 한다. 본 논문에서는 유역 및 하천의 지형공간자료를 활용하여 시범적으로 하천의 생태유량을 산정하였다. 하천의 환경복원에 있어서 지형공간자료는 매우 중요한 기초자료로 활용된다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권3호
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• pp.143-150
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• 1999

Mobile source emissions are important inputs to photochemical air quality models. Since most mobile source emissions are calculated at the county-level, these emission should be geographically allocated to the computational grid cells of a photochemical air quality model prior to running the model. The traditional method for the spatial allocation of these emissions has been to use a "spatial surrogate indicator" such as population, since grid-specific emission calculations are very labor-intensive and expensive, plus the necessary data are often not available for such grid resolutions. Accordingly, new spatial surrogate indicators for mobile source emissions(specifically for highway emissions) were developed using Geographic Information Systems(GIS) tools due to the spatially variable nature of mobile source emissions. These newly developed spatial surrogate indicators appear to be more appropriate for the allocation of highway emissions than the population surrogate indicator. It was also revealed that the conventional spatial allocation method underestimates the maximum levels of air pollutant emmissions.mmissions.

• 대한원격탐사학회지
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• 제36권6_1호
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• pp.1407-1419
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• 2020

지구환경 변화를 파악하는 데 있어서는 장기 시계열의 격자자료가 필수적이며, 기후 재분석장과 위성자료는 대기 및 지표면 변수에 대하여 전 지구 규모에서 주기적이고 정량적인 정보로 활용되고 있다. 본 연구에서는 위성자료의 결측 문제를 해결하기 위한 방안으로 DCT-PLS (penalized least square regression based on discrete cosine transform) 기반의 결측복원 기법을 서로 다른 특성을 가진 복수의 격자자료에 적용하고, 정량적인 검증을 통하여 그 활용성을 평가하였다. 원본 자료와의 객관적인 비교를 위하여 결측이 없는 LDAPS (Local Data Assimilation and Prediction System) 모델로부터 상대습도, 풍속 일자료를 추출하고, MODIS (Moderate Resolution Imaging Spectroradiometer)의 월간 합성 LST (land surface temperature), NDVI (normalized difference vegetation index) 영상을 사용하여, 임의로 생성된 결측 블록이 원본에 매우 가깝게 복원됨을 확인하였고, 4가지 변수 모두에서 상관계수 0.95 이상의 일치도를 나타내었다. DCT-PLS 기반 결측복원 기법은 별도의 보조자료를 필요로 하지 않고, 필요시 시간 및 공간 정보를 모두 활용할 수 있으며, 처리속도가 비교적 빠르기 때문에 현업시스템에 사용될 수 있을 것으로 사료된다.