• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.423-425
• /
• 2003

In this paper, we propose a new scheme for matching specified areas in a satellite image, which is a very efficient method because it can be effectively applied to images that have various features. These features may include different spatial resolution and brightness; sometimes they may different geometrical property. The proposed method can be applied to some application fields such as mosaicing of satellite imagery, GCP matching.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.11 no.4
• /
• pp.64-75
• /
• 2008

Since the current database systems for managing geotechnical investigation results were limited by being described boring test result in point feature, it has been trouble for using other GIS data. Although there are some studies for spatial characteristics of subsurface modeling, it is rather lack of being interoperable with GIS, considering geotechnical engineering facts. This is reason for difficulty of practical uses. In this study, we has developed subsurface spatial information model through extracting needed geotechnical engineering data from geotechnical information DB. The developed geotechnical information clustering program(GEOCL) has made a cluster of boring formation(and formation ratio), classification of layer, and strength characteristics of subsurface. The interpolation of boring data has been achieved through zonal kriging method in the consideration of spatial distribution of created cluster. Finally, we make a subsurface spatial information model to integrate with digital elevation model, and visualize 3-dimensional model by subsurface spatial information viewing program(SSIVIEW). We expect to strengthen application capacity of developed model in subsurface interpretation and foundation design of construction works.

• Spatial Information Research
• /
• v.3 no.1
• /
• pp.29-38
• /
• 1995

• Journal of Korea Spatial Information System Society
• /
• v.6 no.2 s.12
• /
• pp.97-105
• /
• 2004

NGIS project was carried out to accelerate Korea to an information-oriented land. NGIS Project also is to support training projects for GIS specialists as a sub-project. This program has two categories which are long-term courses and short-courses. The long-term courses are for people who want to get a job in SIS(Spatial Information System) field and also for public services personnel who want to acquire the latest SIS technology. Short-term courses are about the latest GIS component technology and utilization spatial data. In this paper, we analyze education programs and training courses relate to SIS. Also we suggest some directions to train specialists for the effective achievement of SIS project. To efficient education for SIS specialist, education programs have courses without repetition and courses are separated by technology type.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.75-80
• /
• 2002

The mainly used technique to rectify satellite images with distortion is to develop a mathematical relationship between the pixel coordinates on the image and the corresponding points on the ground. By defining the relationship between two coordinate systems, a polynomial model is designed and various linear transformations are used. These GCP based geometric correction has performed overall plane to plane mapping. In the overall plane mapping, overall structure of a scene is considered, but local variation is discarded. The highly variant height of region is resampled with distortion in the rectified image. To solve this problem this paper proposed the TIN-based rectification on a satellite image. The TIN based rectification is good to correct local distortion, but insufficient to reflect overall structure of one scene. So, this paper shows the experimental result and the analysis of each rectification model. It also describes the relationship GCP distribution and rectification model. We can choose a geometric correction model as the structural characteristic of a satellite image and the acquired GCP distribution.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.33 no.6
• /
• pp.475-483
• /
• 2015

This study examined the feasibility of using an automatic lens distortion correction (ALDC) camera as the payload for a photogrammetric unmanned aerial vehicle (UAV) system. First, lens distortion for the interior orientation (IO) parameters was estimated. Although previous studies have largely ignored decentering distortion, this study revealed that more than 50% of the distortion of the ALDC camera was caused by decentering distortion. Second, we compared the accuracy of bundle adjustment for camera calibration using three image types: raw imagery without the ALDC option; imagery corrected using lens profiles; and imagery with the ALDC option. The results of image triangulation, the digital terrain model (DTM), and the orthoimage using the IO parameters for the ALDC camera were similar to or slightly better than the results using self-calibration. These results confirm that the ALDC camera can be used in a photogrammetric UAV system using only self-calibration.

• Journal of Astronomy and Space Sciences
• /
• v.20 no.4
• /
• pp.359-364
• /
• 2003

In this paper, we present multi-sensor data fusion for telematics application. Successful telematics can be realized through the integration of navigation and spatial information. The well-determined acquisition of vehicle's position plays a vital role in application service. The development of GPS is used to provide the navigation data, but the performance is limited in areas where poor satellite visibility environment exists. Hence, multi-sensor fusion including IMU (Inertial Measurement Unit), GPS(Global Positioning System), and DMI (Distance Measurement Indicator) is required to provide the vehicle's position to service provider and driver behind the wheel. The multi-sensor fusion is implemented via algorithm based on Kalman filtering technique. Navigation accuracy can be enhanced using this filtering approach. For the verification of fusion approach, land vehicle test was performed and the results were discussed. Results showed that the horizontal position errors were suppressed around 1 meter level accuracy under simulated non-GPS availability environment. Under normal GPS environment, the horizontal position errors were under 40㎝ in curve trajectory and 27㎝ in linear trajectory, which are definitely depending on vehicular dynamics.

• Spatial Information Research
• /
• v.9 no.1
• /
• pp.31-50
• /
• 2001

This study has analyzed GeoTIFF, SDTS, HDF, and BIIF as the representative formats of spatial imagery information with two parts. First is to compare 4 formats with each other based on 4 comparison criteria (extensibility, interchangeability, current widespread use, long-term stability) by analyzing specification of each format. Second is to estimate current use and interchangeability of 4 formats between 5 commercial softwares used commonly. The result shows that GeoTIFF is currently better than three other formats. However, the more various spatial imagery information are and the larger capacity they have, the more formats are developed and updated, which means that only one format should not be considered as a standard format continuously. It is better to provide a standard format proper to the time through continuous research and sustainable policy support should be followed.

• Korean Journal of Remote Sensing
• /
• v.32 no.1
• /
• pp.67-71
• /
• 2016

The surface reflectance is essential to retrieval various indicators related land properties such as vegetation index, albedo and etc. In this study, we estimated surface reflectance using Himawari-8 / Advanced Himawari Imager (AHI) channel data. In order to estimate surface reflectance from Top of Atmosphere (TOA) reflectance, the atmospheric correction is necessary because all of the TOA reflectance from optical sensor is affected by gas molecules and aerosol in the atmosphere. We used Second Simulation of a Satellite Signal in the Solar Spectrum Vector (6SV) Radiative Transfer Model (RTM) to correct atmospheric effect, and Look-Up Table (LUT) to shorten the calculation time. We verified through comparison Himawri-8 / AHI surface reflectance and Proba-V S1 products. As a result, bias and Root Mean Square Error (RMSE) are calculated about -0.02 and 0.05.

• Korean Journal of Remote Sensing
• /
• v.32 no.1
• /
• pp.61-65
• /
• 2016

Importance of remote sensing for surface is increased than past. So many countries try to many ways to retrieve surface reflectance. In this study, we study a Bidirectional Reflectance Distribution Function (BRDF) to retrieve surface reflectance. We apply BRDF using observed surface reflectance of SPOT/VEGETATION (VGT-S1) and angular data to get Bidirectional Reflectance Distribution (BRD) coefficients for calculating scattering. And then we apply BRDF in the opposite direction with BRD coefficients and angular data to retrieve Background Surface Reflectance (BSR). The range of BSR is not over $0.4{\mu}m$ (blue), $0.45{\mu}m$ (red), $0.55{\mu}m$ (NIR). And for validation we compare BSR with VGT-S1, there are bias is from 0.0116 to 0.0158 and RMSE is from 0.0459 to 0.0545. As a result, we confirm that BSR is similar to VGT-S1.