• Journal of Korean Society for Geospatial Information Science
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• v.2 no.2 s.4
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• pp.99-108
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• 1994

In this thesis, we propose the 3D terrain modelling method for the better understanding of the geographic information. The process of 3D terrain medelling consists of three steps. The first step is to obtain real-world data from satellite images and stored in the form of DEM(Digital Elevation Model). The second one is to extract the meaningful data from DEM data based on LOD(Level Of Detail). And the third is to construct the 3D surface by TIN(Triangulated Irregular Network) with the extracted meaingful data. The proposed dynamic TIN reconstruction algorithm locally reconstruct the existed TIN model with the additional a new point. In this way, we can construct the TIN with the reduced time and can simulated 3D terrain model in real time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1B
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• pp.120-127
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• 2000

In this paper, we propose multispectral image compression using classified interband prediction and vector quantization in wavelet domain. This method classifies each region considering reflection characteristics of each band in image data. In wavelet domain, we perform the classified intraband VQ to remove intraband redundancy for a reference band image that has the lowest spatial variance and the best correlation with other band. And in wavelet domain, we perform the classifled interband prediction to remove interband redundancy for the remaining bands. Then error wavelet coefficients between original image and predicted image are intraband vector quantized to reduce prediction error. Experiments on remotely sensed satellite image show that coding efficiency of theproposed method is better than that of the conventional method.

• 한국공간정보시스템학회:학술대회논문집
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• 2002.03a
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• pp.59-64
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• 2002

컴퓨터 그래픽스 기술과 H/W의 발달로 3D GIS에 대한 연구가 활발히 진행되고 있다. 최근 3D GIS에 대한 활발한 연구 중 3D 가상도시의 구축이 중요한 연구로 떠오르고 있다. 3D 가상도시는 국방, 교통, 통신, 지적, 지하시설물, 관광, 도시계획, 도시모델링 등에 다양하게 활용될 수 있다. 현재 우리나라에서 3D 가상도시의 구축은 미약하지만 앞으로 그 수요는 더욱 더 많아질 것이다. 3D 가상도시의 구축에는 GIS, 컴퓨터 그래픽스, Database, 자료구조, 3D 모델링 등의 다양한 기술이 필요하다. 3D 가상도시의 구축의 방법은 크게 1/1,000수치지도+실제측량, 1/1,000수치지도+입체 인공위성 영상+수치사진측량, 1/1,000수치지도+항공사진측량 도화원도, 1/1,000수치지도+항공레이저스캐닝의 방법을 적용해 볼 수 있다. 현재 우리나라 여건상 첫 번째 방법이 가장 일반적으로 사용이 되나 도화원도에 대한 규제를 완화하여 세 번째 방법을 적용하는 것이 가장 효과적일 것이다. 3D 가상도시는 인터넷 기술과 접목이 되어 3D Web GIS의 형태로 앞으로의 GIS 주류를 이룰 것이다. 그러나 국내에서 3D 가상도시의 구축에 관한 연구는 미약한 수준이다. 3D 자료취득, 자료처리, 모델링 부문에 대한 연구가 시급하다.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.8
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• pp.764-770
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• 2001

In this paper, we propose a novel PCI bus based parallel fuzzy inference system for transferring and inferencing the large volumes of fuzzy data in high speed. For this, the PCI 9050 interface chip is used to connect a local bus design as a PCI target core using FPGA to the PCI bus. We design and implement the PCI target core by using VHDL to be processed in parallel by considering the points of parallelyzing each element of the membership functions and each block of the condition and/or consequent parts. The proposed system can be used in a system requiring a rapid inference time in a real-time system or pattern recognition on the large volume of satellite images that have many inference variables in the condition and consequent parts.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.447-452
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• 2006

The remote sensing technique was applied to enhance the water qualify model validation in a large water body. Since the satellite image usually covers the wide surface area of a large water body, it can compensate for the lark of measured data points required for model calibration and verification. This paper describes the analysis of Landsat FTM+images collected on April 29th and September 4th in year 2000 to evaluate surface water temperature of Lake Paldang. The water temperature data obtained from the satellite image were compared with model results by estimating three different methods of error criteria. The residual ratios on April 29th and September 4th were 0.13 and 0.04 respectively. This showed that the model result accords with the data obtained from the process of satellite image. Without considering atmospheric interference, however, transformation process of satellite image causes relatively large residual ratio in the surface water temperature distribution pattern on April 29th. In the future study, therefore, the atmospheric properties of image acquisition point needs to be considered for the application of radiance transformation model.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1283-1297
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• 2023

Mid-wave infrared (MWIR) imagery, due to its ability to capture the temperature of land cover and objects, serves as a crucial data source in various fields including environmental monitoring and defense. The KOMPSAT-3A satellite acquires MWIR imagery with high spatial resolution compared to other satellites. However, the limited spatial resolution of MWIR imagery, in comparison to electro-optical (EO) imagery, constrains the optimal utilization of the KOMPSAT-3A data. This study aims to create a highly visible MWIR fusion image by leveraging the edge information from the KOMPSAT-3A panchromatic (PAN) image. Preprocessing is implemented to mitigate the relative geometric errors between the PAN and MWIR images. Subsequently, we employ a pre-trained pixel difference network (PiDiNet), a deep learning-based edge information extraction technique, to extract the boundaries of objects from the preprocessed PAN images. The MWIR fusion imagery is then generated by emphasizing the brightness value corresponding to the edge information of the PAN image. To evaluate the proposed method, the MWIR fusion images were generated in three different sites. As a result, the boundaries of terrain and objects in the MWIR fusion images were emphasized to provide detailed thermal information of the interest area. Especially, the MWIR fusion image provided the thermal information of objects such as airplanes and ships which are hard to detect in the original MWIR images. This study demonstrated that the proposed method could generate a single image that combines visible details from an EO image and thermal information from an MWIR image, which contributes to increasing the usage of MWIR imagery.

• Aerospace Engineering and Technology
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• v.4 no.2
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• pp.220-229
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• 2005

The Earth observation imagery from satellite provide valuable informations for the central government, local governments and diverse public organizations. The analysis of applications and data, which are sold by commercial distributors of Earth observation satellite data, shows this phenomenon clearly. The Government of Republic of Korea established and carried out a national space development plan to meet the national needs for remotely sensed imagery. After this national space development plan and on behalf of Korean government KARI has developed and launched successfully the KOMPSAT-1 and operates it up to now. KARI is now to launch by the end of year 2005 another optical remote sensing satellite with very high resolution and named as KOMPSAT-2. For the application of such very high resolution remotely sensed data the product validation should be done carefully and this product validation require lots of ancillary data such as in-situ measurements. For the purpose of diverse ancillary data acquisition joint work with other nations, related institutes and international bodies is essential. In this paper the status of Korean European Cooperations will be introduced, which are derived by KARI, ARCS and ESA for the wide use of KOMPSAT data in Europe.

• Journal of Aerospace System Engineering
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• v.16 no.5
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• pp.1-7
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• 2022

Recently, satellites equipped with high-performance electronics have required higher power consumption because of the advancement of satellite missions. For this reason, the size of the solar panel is gradually increasing to meet the required power budget. Increasing the size and weight of the solar panel is one of the factors that induce the elastic vibration of the flexible solar panel during the highly agile maneuvering of the satellite or the mode of vibration coupling to the satellite or the mode of vibration coupling to the micro-jitter from the on-board appendages. Previously, an additional damper system was applied to reduce the elastic vibration of the solar panel, but the increase in size and mass of system was inevitable. In this study, to overcome the abovementioned limitations, we proposed a high -damping yoke structure consisting of a superplastic SMA(Shape Memory Alloy) laminating a thin FR4 layer with viscoelastic tape on both sides. Therefore, this advantage contributes to system simplicity by reducing vibrations with small volume and mass without additional system. The effectiveness of the proposed superelastic SMA multilayer solar panel yoke was validated through free vibration testing and temperature testing using a solar panel dummy.

• The Korean Journal of Ecology
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• v.28 no.4
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• pp.215-222
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• 2005

MODIS (Moderate Resolution Image Spectrometer) is a core satellite sensor boarded on Terra and Aqua satellite of NASA Earth Observing System since 1999 and 2001, respectively. MODIS LAI, FPAR, and GPP provide useful means to monitor plant phonology and material cycles in terrestrial ecosystems. In this study, LAI, FPAR, and GPP in Korea were evaluated and errors associated with cloud contamination on MODIS pixels were eliminated for years $2001\sim2003$. Three-year means of cloud-corrected annual GPP were 1836, 1369, and 1460g C $m^{-2}y^{-1}$ for evergreen needleleaf forest, deciduous broadleaf forest, and mixed forest, respectively. The cloud-originated errors were 8.5%, 13.1%, and 8.4% for FPAR, LAI, and GPP, respectively. Summertime errors from June to September explained by 78% of the annual accumulative errors in GPP. This study indicates that cloud-originated errors should be mitigated for practical use of MODIS vegetation products to monitor seasonal and annual changes in plant phonology and vegetation production in Korea.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.2 s.32
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• pp.13-20
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• 2005

Upon the request of balanced development of the country and making inroads into the continent of China the development of the west coast was begun in the late 1980s, which has been being continued till recently under the blueprint of making the western part of the capital region to be the hub of northeastern Asia. As more lively development is expected to continue in the area, there are many occurrences of change in topology and terrain in the west coast. This study was done to detect the topographic and terrain change of the vicinity of the west coast. To make the basic map of the change in topology and terrain, the mosaic images were made using landsat images. The accuracy of the images was examined by comparing them with GCP through 1:25,000's digital map. After that, among the resultant images of the 1970s and 2000s, those of Sihwa, Hwaong and Ansan, the lands reclaimed by drainage were compared to observe the change in the area. From the results, it was concluded that, in case of the land the topological change was not so big due to the development in the reclaimed land or the bare land, and the area of agriculture and downtown increased, the drainage and bare land area decreased by comparing the change of land use.