• Title/Summary/Keyword: remote sensing

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Implementation of Geosensor Interface using Object Oriented Design Pattern (객체지향 설계 유형에 의한 지오센서 인터페이스 구현)

  • Baek, Jeong-Ho;Lee, Hong-Ro
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.3
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    • pp.193-206
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    • 2006
  • This paper proposes The Efficient method that should design Geosensor model based on object oriented design pattern and implement the Geosensor network interface system using JBuilder. Such as geosensor technology will be to a new research paradigm of GIS which can manage a great quantity of field information by means of constructing the real time remote sensing network. The technology that integrates object oriented design pattern Geosensor interface network with GIS will be necessary elements that satisfy the function of GIS increasing day by day. Therefore, we would like to utilize GoF design pattern in order to change for the better object oriented Geosensor middleware. This paper shall contribute to implementing the optimal Geosensor interface that can develop reusable, modular and modifiable software by using the object oriented design pattern.

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A Study on the Accuracy Improvement of Land Surface Temperature Extraction by Remote Sensing Data (원격탐사 자료에 의한 지표온도추출 정확도 향상에 관한 연구)

  • Um, Dae-Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.2
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    • pp.159-172
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    • 2006
  • In this study, the series of Landsat TM/ETM+ images was acquired to extract land surface temperature for wide-area and executed geometric correction and radiometric correction. And the land surface temperature was extracted using NASA Model, and achieved the first correction by performing land coverage category for study area and applied characteristic emission rate. Land surface temperature which was acquired by the first correction was analyzed in correlation with Meteorological Administration's temperature data by regression analysis, and established correction formula. And I wished to improve accuracy of land surface temperature extraction using satellite image by second correcting deviations between two data using establishing correction formula. As a result, land surface temperature acquired by 1st and 2st correction could be corrected in mean deviation of about ${\pm}3.0^{\circ}C$ with Meteorological Administration data. Also, I could acquire land surface temperature about study area by higher accuracy by applying to other Landsat images for re-verification of study results.

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Analysis of Climate Change Sensitivity of Forest Ecosystem using MODIS Imagery and Climate Information (MODIS NDVI 및 기후정보 활용 산림생태계의 기후변화 민감성 분석)

  • SONG, Bong-Geun;PARK, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.3
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    • pp.1-18
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    • 2018
  • The purpose of this study is to analyze sensitivity of forest ecosystem to climate change using spatial analysis methods focused on 6 national parks. To analyze, we constructed MODIS NDVI and temperature of Korea Meteorologic Administration based on 1km spatial resolution and 16 days. And we conducted time-series and correlation analysis using MODIS NDVI and temperature. A most sensitive region to climate change is Jirisa National Park(r=0.434) and Seoraksan National Park(r=0.415), there is the highest mean correlation coefficient. The sensitivity of forest ecosystem varied according to habitat characteristics and forest types in national park. In Abies koreana of Hallsan Nation Park, temperature has raised, but NDVI has decreased. these results will be based data of climate change adaption policy for protecting forest ecosystem.

A Development of Enhanced Automatic Lineament Extraction Algorithm and its Application (자동 선구조 추출 알고리즘의 개발과 적용사례)

  • Choi Eun-Young;Choi Dong-Seok;Choi Hyoun-Seok;Lim Tae-Geun;Jung Lae-Chul;Yoon Wang-Jung
    • Geophysics and Geophysical Exploration
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    • v.6 no.1
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    • pp.7-12
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    • 2003
  • The lineament extraction from satellite images is important in the geologic studies including groundwater and mineral exploration, groundwater survey, natural hazard analysis, and many others. The lineaments in remote sensing images are identified by the difference of pixel values or brightness. Since the visual interpretation is apt to be influenced by the knowledges and experiences, many of the automatic lineament detection algorithms are developed to ensure the objectives and efficient outputs. DSTA (dynamic segment tracing algorithm) is one of such algorithms, which can be applied to not only mountainous area but also alluvial area. However, when the alluvial area is wider than mountain region, somewhat severe noises are generated. To reduce such noises, AERA (alluvial effect reducing algorithm) is proposed and tested for the image which contains mountains, cultivated land and urban area. Upon the application of AERA, alluvial effects in lineament extraction from satellite image are substantially reduced.

Semi-Automated Extraction of Geographic Information using KOMPSAT 2 : Analyzing Image Fusion Methods and Geographic Objected-Based Image Analysis (다목적 실용위성 2호 고해상도 영상을 이용한 지리 정보 추출 기법 - 영상융합과 지리객체 기반 분석을 중심으로 -)

  • Yang, Byung-Yun;Hwang, Chul-Sue
    • Journal of the Korean Geographical Society
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    • v.47 no.2
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    • pp.282-296
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    • 2012
  • This study compared effects of spatial resolution ratio in image fusion by Korea Multi-Purpose SATellite 2 (KOMPSAT II), also known as Arirang-2. Image fusion techniques, also called pansharpening, are required to obtain color imagery with high spatial resolution imagery using panchromatic and multi-spectral images. The higher quality satellite images generated by an image fusion technique enable interpreters to produce better application results. Thus, image fusions categorized in 3 domains were applied to find out significantly improved fused images using KOMPSAT 2. In addition, all fused images were evaluated to satisfy both spectral and spatial quality to investigate an optimum fused image. Additionally, this research compared Pixel-Based Image Analysis (PBIA) with the GEOgraphic Object-Based Image Analysis (GEOBIA) to make better classification results. Specifically, a roof top of building was extracted by both image analysis approaches and was finally evaluated to obtain the best accurate result. This research, therefore, provides the effective use for very high resolution satellite imagery with image interpreter to be used for many applications such as coastal area, urban and regional planning.

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Remote Sensing of Soil Moisture Change Using a Differential Interferometry Technique (차분 간섭 기법을 이용한 지표면 수분함유량 변화 탐지)

  • Park, Sin-Myeong;Oh, Yisok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.4
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    • pp.459-465
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    • 2013
  • This paper presents a differential interferometry technique for soil moisture change detection by measuring surface-height variation. COSMO-SkyMed SAR images were used to verify the DInSAR(differential interferometric SAR) technique. The soil penetration depth changes according to soil moisture, that causes phase change of the received signal. The height of soil surface and its displacement can be detected by a radar interferometry technique using phase difference of two received signals. To retrieve displacement variation, one of three SAR images is used as a reference image. Reference image and other two images are processed by the differential interferometry technique in the same area. The soil moisture was measured for the test sites to verify the DInSAR technique. The penetration depth is calculated by using the in-situ measured soil moisture data and it is compared with the displacement values acquired by the DInSAR technique.

A Study on the Performance of Deep learning-based Automatic Classification of Forest Plants: A Comparison of Data Collection Methods (데이터 수집방법에 따른 딥러닝 기반 산림수종 자동분류 정확도 변화에 관한 연구)

  • Kim, Bomi;Woo, Heesung;Park, Joowon
    • Journal of Korean Society of Forest Science
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    • v.109 no.1
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    • pp.23-30
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    • 2020
  • The use of increased computing power, machine learning, and deep learning techniques have dramatically increased in various sectors. In particular, image detection algorithms are broadly used in forestry and remote sensing areas to identify forest types and tree species. However, in South Korea, machine learning has rarely, if ever, been applied in forestry image detection, especially to classify tree species. This study integrates the application of machine learning and forest image detection; specifically, we compared the ability of two machine learning data collection methods, namely image data captured by forest experts (D1) and web-crawling (D2), to automate the classification of five trees species. In addition, two methods of characterization to train/test the system were investigated. The results indicated a significant difference in classification accuracy between D1 and D2: the classification accuracy of D1 was higher than that of D2. In order to increase the classification accuracy of D2, additional data filtering techniques were required to reduce the noise of uncensored image data.

Detection of Urban Expansion and Surface Temperature Change using Landsat Satellite Imagery (Landsat 위성영상을 이용한 도시확장 및 지표온도 변화 탐지)

  • Song, Yeong-Sun
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.4 s.34
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    • pp.59-65
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    • 2005
  • It is very important to detect land cover/land use change from the past and to use it for future urban plan. This paper investigated the application of Landsat satellite imagery for detecting urban growth and assessing its impact on surface temperature in the region. Land cover/land use change detection was carried out by using 30m resolution Landsat satellite images and hierarchial approach was introduced to detect more detail change on the changing area through high resolution aerial photos. Also, surface temperature according to land cover/land use was calculated from Landsat TM thermal infrared data and compared with real temperature to analyze the relationship between urban expansion and surface temperature. As a result, the urban expansion has raised surface radiant temperature in the urbanized area. The method using remote sensing data based on GIS was found to be effective in monitoring and analysing urban growth and in evaluating urbanization impact on surface temperature.

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Positional Accuracy of Road and Underground Utility Information (도로기반시설물정보의 위치정확도에 관한 연구)

  • Park, Hong-Gi;Shin, Dong-Bin
    • Journal of Korean Society for Geospatial Information Science
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    • v.10 no.4 s.22
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    • pp.51-60
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    • 2002
  • As the use of GIS becomes more widespread, the quality and source of data is becoming more of a concern among users. But accuracy is a component of quality, and the positional accuracy is a component of total accuracy. If only we consider the positional accuracy, simultaneously collecting technology of location and attribute information, whether it be manually, using conventional surveying method, GPS, or remote sensing, is a practical way of insuring that location and attribute information are correctly correlated. This study analyse the positional accuracy from a view-point of user and supplier, which is the considerations that can ensure quality level and continuously maintain the road and underground utility information. The positional accuracy of road and underground utility information are considered as two categories - expected accuracy of data collection procedure, required accuracy of data usage process. And the project manager must consider the cost/benefit view of data generation in order to determine the surveying method.

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Detection of Sea Fog by Combining MTSAT Infrared and AMSR Microwave Measurements around the Korean peninsula (MTSAT 적외채널과 AMSR 마이크로웨이브채널의 결합을 이용한 한반도 주변의 해무 탐지)

  • Park, Hyungmin;Kim, Jae Hwan
    • Atmosphere
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    • v.22 no.2
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    • pp.163-174
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    • 2012
  • Brightness temperature (BT) difference between sea fog and sea surface is small, because the top height of fog is low. Therefore, it is very difficult to detect sea fog with infrared (IR) channels in the nighttime. To overcome this difficulty, we have developed a new algorithm for detection of sea fog that consists in three tests. Firstly, both stratus and sea fog were discriminated from the other clouds by using the difference between BTs $3.7{\mu}m$ and $11{\mu}m$. Secondly, stratus occurring at a level higher than sea fog was removed when the difference between cloud top temperature and sea surface temperature (SST) is smaller than 3 K. In this process, we used daily SST data from AMSR-E microwave measurements that is available even in the presence of cloud. Then, the SST was converted to $11{\mu}m$ BT based on the regressed relationship between AMSR-E SST and MTSAT-1R $11{\mu}m$ BT at 1733 UTC over clear sky regions. Finally, stratus was further removed by using the homogeneity test based on the difference in cloud top texture between sea fog and stratus. Comparison between the retrievals from our algorithm and that from Korea Meteorological Administration (KMA) algorithm, shows that the KMA algorithm often misconceived sea fog as stratus, resulting in underestimating the occurrence of sea fog. Monthly distribution of sea fog over northeast Asia in 2008 was derived from the proposed algorithm. The frequency of sea fog is lowest in winter, and highest in summer especially in June. The seasonality of the sea fog occurrence between East and West Sea was comparable, while it is not clearly identified over South Sea. These results would serve to prevent the possible occurrence of marine accidents associated with sea fog.