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  • Title/Summary/Keyword: Spatial imagery

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Case Study of Oil Spill Monitoring Caused by Maritime Casualties Using Satellite Data in 2014 (해양사고에 의한 유출유 모니터링 사례 소개와 향후 방향)

  • Yang, Chan-Su
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2014.06a
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    • pp.79-80
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    • 2014
  • Most of marine pollution have been occurred by oil spill accidents resulted from ship accidents in South Korea. This year there were two large oil spill accidents: the Yeosu Oil Spill Accident (2014.01.31.(Fri.) 09:35 LT) and the Captain Vangelis L. Oil Spill Accident (2014.02.15.(Sat.) 14:00 LT). In general, Synthetic Aperture Radar (SAR) is used in monitoring and detection of oil dumping and spilled oils by accident at sea. Therefore it is expected that KOMPSAT-5, launched successfully last year, will take part in that mission during a normal operation mode. After the two accidents, high spatial resolution optical satellite data including KOMPSAT-3 were acquired February 2 and 14, 2014. In this presentation, we analyzed optical properties of spilled oils from optical satellite imagery to estimate the spilled area and the volume at each region. Finally, a satellite application planning for ocean surveillance in South Korea will be presented.

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Monitoring Onion Growth using UAV NDVI and Meteorological Factors

  • Na, Sang-Il;Park, Chan-Won;So, Kyu-Ho;Park, Jae-Moon;Lee, Kyung-Do
    • Korean Journal of Soil Science and Fertilizer
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    • v.50 no.4
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    • pp.306-317
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    • 2017
  • Unmanned aerial vehicles (UAVs) became popular platforms for the collection of remotely sensed data in the last years. This study deals with the monitoring of multi-temporal onion growth with very high resolution by means of low-cost equipment. The concept of the monitoring was estimation of multi-temporal onion growth using normalized difference vegetation index (NDVI) and meteorological factors. For this study, UAV imagery was taken on the Changnyeong, Hapcheon and Muan regions eight times from early February to late June during the onion growing season. In precision agriculture frequent remote sensing on such scales during the vegetation period provided important spatial information on the crop status. Meanwhile, four plant growth parameters, plant height (P.H.), leaf number (L.N.), plant diameter (P.D.) and fresh weight (F.W.) were measured for about three hundred plants (twenty plants per plot) for each field campaign. Three meteorological factors included average temperature, rainfall and irradiation over an entire onion growth period. The multiple linear regression models were suggested by using stepwise regression in the extraction of independent variables. As a result, NDVIUAV and rainfall in the model explain 88% and 68% of the P.H. and F.W. with a root mean square error (RMSE) of 7.29 cm and 59.47 g, respectively. And NDVIUAV in the model explain 43% of the L.N. with a RMSE of 0.96. These lead to the result that the characteristics of variations in onion growth according to NDVIUAV and other meteorological factors were well reflected in the model.

Application of Evaporative Stress Index (ESI) for Satellite-based Agricultural Drought Monitoring in South Korea (위성영상기반 농업가뭄 모니터링을 위한 Evaporative Stress Index (ESI)의 적용성 평가)

  • Yoon, Dong-Hyun;Nam, Won-Ho;Lee, Hee-Jin;Hong, Eun-Mi;Kim, Taegon;Kim, Dae-Eui;Shin, An-Kook;Svoboda, Mark D.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.6
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    • pp.121-131
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    • 2018
  • Climate change has caused changes in environmental factors that have a direct impact on agriculture such as temperature and precipitation. The meteorological disaster that has the greatest impact on agriculture is drought, and its forecasts are closely related to agricultural production and water supply. In the case of terrestrial data, the accuracy of the spatial map obtained by interpolating the each point data is lowered because it is based on the point observation. Therefore, acquisition of various meteorological data through satellite imagery can complement this terrestrial based drought monitoring. In this study, Evaporative Stress Index (ESI) was used as satellite data for drought determination. The ESI was developed by NASA and USDA, and is calculated through thermal observations of GOES satellites, MODIS, Landsat 5, 7 and 8. We will identify the difference between ESI and other satellite-based drought assessment indices (Vegetation Health Index, VHI, Leaf Area Index, LAI, Enhanced Vegetation Index, EVI), and use it to analyze the drought in South Korea, and examines the applicability of ESI as a new indicator of agricultural drought monitoring.

Generation of Building and Contour Layers for Digital Mapping Using LiDAR Data (LiDAR 데이터를 이용한 수치지도의 건물 및 등고선 레이어 생성)

  • Lee Dong-Cheon;Yom Jae-Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.3
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    • pp.313-322
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    • 2005
  • Rapid advances in technology and changes in human and cultural activities bring about changes to the earth surface in terms of spatial extension as well as time frame of the changes. Such advances introduce shorter updating frequency of maps and geospatial database. To satisfy these requirements, recent research efforts in the geoinformatics field have been focused on the automation and speeding up of the mapping processes which resulted in products such as the digital photogrammetric workstation, GPSIINS, applications of satellite imagery, automatic feature extraction and the LiDAR system. The possibility of automatically extracting buildings and generating contours from airborne LiDAR data has received much attention because LiDAR data produce promising results. However, compared with the manually derived building footprints using traditional photogrammetric process, more investigation and analysis need to be carried out in terms of accuracy and efficiency. On the other hand, generation of the contours with LiDAR data is more efficient and economical in terms of the quality and accuracy. In this study, the effects of various conditions of the pre-processing phase and the subsequent building extraction and contour generation phases for digital mapping have on the accuracy were investigated.

A Study on the Integrated Use of Digital Topographic Maps and Image Data (수치지형도와 영상자료의 연계 활용방안에 관한 연구)

  • Kim, Kye-Hyun;Lee, Kyong-Suk;Jin, Heui-Chae
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.1 s.13
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    • pp.21-28
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    • 1999
  • NGIS and other related public projects have contributed to the generalized use of the digital maps. The accuracy and cost-effectiveness of such digital maps can be enhanced from the integrated use with airphotos and satellite imagery. This study mainly focuses on the investigation of a efficient way of integrating the digital map and image data along with searching for a proper standard format for the easier distribution of image data. This includes a thorough investigation of the available oversea image data-DoQ, DEM, DRG-and exisiting data transfer format such as widely used Geo TIFF and BIIF, supported by ISO. Also, major advantages and problems from integrating both data have been discussed to seek alternatives. The major conclusion from the study includes the need for more supports to activate the use of image data by policy-makers and the establishment of standards towards BIIF considering the accuracy, exchangeability, and trends.

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Monitoring suspended sediment distribution using Landsat TM/ETM+ data in coastal waters of Seamangeum, Korea

  • Min Jee-Eun;Ryu Joo-Hyung;P Shanmugam;Ahn Yu-Hwan;Lee Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.340-343
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    • 2004
  • Since the tide embankment construction started in 1991, the coastal environment in and around the Saemangeum area has undergone changes rapidly, there is a need for monitoring the environmental change in this region. Owing to high temporal and spatial heterogeneity of the coastal ecosystem and processes as well as the expense with traditional filed sampling at discrete locations, satellite remote sensing measurements offer a unique perspective on mapping a large region simultaneously because of the synoptic and repeat coverage and that quantitative algorithms used for estimating constituents' concentration in the coastal environments. Thus, the main objectives of the present study are to analyze the retrieved Suspended Sediment (SS) pattern to predict changes after the commencement of the tide embankment construction work in 1991. This is accomplished with a series of the Landsat TM/ETM+ imagery acquired from 1985-2002 (a total of 18 imageries). Instead of a simple empirical algorithm, we implement an analytical SS algorithm, developed by Ahn et al. (2003), which is especially developed for estimating SS concentration (SSC) in Case-2 waters. The results show that there is a significant change in SS pattern, which is mainly influenced by the tide and tidal height after the construction of the embankment work. As the construction progressed, the distribution pattern of SS has greatly changed, and the rate of SS concentration in the gap area of the dyke of post-construction has significantly increased.

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An analysis of Electro-Optical Camera (EOC) on KOMPSAT-1 during mission life of 3 years

  • Baek Hyun-Chul;Yong Sang-Soon;Kim Eun-Kyou;Youn Heong-Sik;Choi Hae-Jin
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.512-514
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    • 2004
  • The Electro-Optical Camera (EOC) is a high spatial resolution, visible imaging sensor which collects visible image data of the earth's sunlit surface and is the primary payload on KOMPSAT-l. The purpose of the EOC payload is to provide high resolution visible imagery data to support cartography of the Korean Peninsula. The EOC is a push broom-scanned sensor which incorporates a single nadir looking telescope. At the nominal altitude of 685Km with the spacecraft in a nadir pointing attitude, the EOC collects data with a ground sample distance of approximately 6.6 meters and a swath width of around 17Km. The EOC is designed to operate with a duty cycle of up to 2 minutes (contiguous) per orbit over the mission lifetime of 3 years with the functions of programmable gain/offset. The EOC has no pointing mechanism of its own. EOC pointing is accomplished by right and left rolling of the spacecraft, as needed. Under nominal operating conditions, the spacecraft can be rolled to an angle in the range from +/- 15 to 30 degrees to support the collection of stereo data. In this paper, the status of EOC such as temperature, dark calibration, cover operation and thermal control is checked and analyzed by continuously monitored state of health (SOH) data and image data during the mission life of 3 years. The aliveness of EOC and operation continuation beyond mission life is confirmed by the results of the analysis.

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The Applicability for Earth Surface Monitoring Based on 3D Wavelet Transform Using the Multi-temporal Satellite Imagery (다중시기 위성영상을 이용한 3차원 웨이블릿 변환의 지구모니터링 응용가능성 연구)

  • Yoo, Hee-Young;Lee, Ki-Won
    • Journal of the Korean earth science society
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    • v.32 no.6
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    • pp.560-574
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    • 2011
  • Satellite images that have been obtained periodically and continuously are very effective data to monitor the changes of Earth's surface. Traditionally, the studies on change detection using satellite images have mainly focused on comparison between two results after analyzing two images respectively. However, the interests in researches to catch smooth trends and short duration events from continual multi-temporal images have been increased recently. In this study, we introduce and test an approach based on 3D wavelet transform to analyze the multi-temporal satellite images. 3D wavelet transform can reduce the dimensions of data conserving main trends. Also, it is possible to extract important patterns and to analyze spatial and temporal relations with neighboring pixels using 3D wavelet transform. As a result, 3D wavelet transform is useful to capture the long term trends and short-term events rapidly. In addition, we can expect to get new information through sub-bands of 3D wavelet transform which provide different information by decomposed direction.

Fruit Fly Optimization based EEG Channel Selection Method for BCI (BCI 시스템을 위한 Fruit Fly Optimization 알고리즘 기반 최적의 EEG 채널 선택 기법)

  • Yu, Xin-Yang;Yu, Je-Hun;Sim, Kwee-Bo
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.3
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    • pp.199-203
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    • 2016
  • A brain-computer interface or BCI provides an alternative method for acting on the world. Brain signals can be recorded from the electrical activity along the scalp using an electrode cap. By analyzing the EEG, it is possible to determine whether a person is thinking about his/her hand or foot movement and this information can be transferred to a machine and then translated into commands. However, we do not know which information relates to motor imagery and which channel is good for extracting features. A general approach is to use all electronic channels to analyze the EEG signals, but this causes many problems, such as overfitting and problems removing noisy and artificial signals. To overcome these problems, in this paper we used a new optimization method called the Fruit Fly optimization algorithm (FOA) to select the best channels and then combine them with CSP method to extract features to improve the classification accuracy by linear discriminant analysis. We also used particle swarm optimization (PSO) and a genetic algorithm (GA) to select the optimal EEG channel and compared the performance with that of the FOA algorithm. The results show that for some subjects, the FOA algorithm is a better method for selecting the optimal EEG channel in a short time.

Forecast of Land use Change for Efficient Development of Urban-Agricultural city (도농도시의 효율적 개발을 위한 토지이용변화예측)

  • Kim, Se-Kun;Han, Seung-Hee
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.2
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    • pp.73-79
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    • 2012
  • This study attempts to analyze changes in land use patterns in a compound urban and agricultural city Kimje-si, using LANDSAT TM imagery and to forecast future changes accordingly. As a new approach to supervised classification, HSB(Hue, Saturation, Brightness)-transformed images were used to select training zones, and in doing so classification accuracy increased by more than 5 percent. Land use changes were forecasted by using a cellular automaton algorithm developed by applying Markov Chain techniques, and by taking into account classification results and GIS data, such as population of the pertinent region by area, DEMs, road networks, water systems. Upon comparing the results of the forecast of the land use changes, it appears that geographical features had the greatest influence on the changes. Moreover, a forecast of post-2030 land use change patterns demonstrates that 21.67 percent of mountain lands in Kimje-si is likely to be farmland, and 13.11 percent is likely to become city areas. The major changes are likely to occur in small mountain lands located in the heart of the city. Based on the study result, it seems certain that forecasting future land use changes can help plan land use in a compound urban and agricultural city to procure food resources.