• Journal of Aerospace System Engineering
• /
• v.18 no.1
• /
• pp.88-98
• /
• 2024

In this paper, an Automatic Terrain Following (ATF) Simulator using Digital Terrain Elevation Data (DTED) was proposed. This ATF Simulator consists of a Flight Simulator, a Radar Simulator, and a Terrain Following Computer (TFC) Simulator. DTED and radar scan data generated with DTED were used as the terrain information necessary for terrain following. The ATF Simulator provides three modes of operation: a passive mode that uses DTED, an active mode that uses radar scan data, and a hybrid mode that uses both. We developed an ATF Simulator that could reduce the cost and time required to develop a terrain following system using the LabVIEW development environment and the MATLAB App Designer development environment. It was verified by confirming that the ATF Simulator met all functional requirements.

• Journal of Navigation and Port Research
• /
• v.35 no.1
• /
• pp.51-56
• /
• 2011

In this paper, we presents an algorithm which restores lost data or increases resolution of a DTM(Digital terrain model) using fractal theory. Terrain information(fractal dimension and standard deviation) around the patch to be restored is extracted and then with this information and original data, the elevations of cells are interpolated using the random midpoint displacement method. The results of the proposed algorithm are compared with those of the bilinear and bicubic methods on a fractal terrain map.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.4
• /
• pp.285-291
• /
• 2012

The paper experimentally verifies the performance of Terrain-Aided Navigation (TAN) using an interferometric radio altimeter, which is recently used due to its accuracy. First, we propose a TAN system that utilizes an interferometric radio altimeter as a measurement system. Second, we implement extended Kalman filter, unscented Kalman filter, and particle filter to evaluate the performance of TAN according to the selection of filters and the difference of environments.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.6
• /
• pp.515-522
• /
• 2012

CFIT(Controlled Flight Into Terrain) is one of the major causes of aircraft accidents. In order to solve this problem, GPWS(Ground Proximity Warning System) is used to generate terrain collision warning using the distance between the aircraft and the underneath ground. Since the GPWS uses the vertical clearance only, it frequently generates false warnings. In this study, a terrain/obstacle collision avoidance warning algorithm was developed for fast flying and highly maneuvering fighters using the flight status and the geographic information. This algorithm condsiders the overall delay in the aircraft reactive motion including the pilot's reaction time. The paper presents a detailed logic and test methods.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.343-352
• /
• 2011

For optimizing railroad designs, setting up shape and specifications of facilities harmonized and coincide with local topography based on absolute location information, correct construction quantity's output and proper land's security etc are key matters, and also clear and advanced surveying standards and technical provision shall become priority so as to satisfy them. Therefore, this study analyzed and researched on surveying standards and technical provision's status in current railroad design's cases, and then attempts to suggest establishment of design surveying standard, procedures, and methods together with its practical scheme.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.3 no.2 s.5
• /
• pp.1-8
• /
• 2004

Characteristics of digital broadcasting are multi-channel, high-definition and multi-function. especially, multi-function is enable us to do a variety of services except for an image and a voice. This paper, therefore, is analyzed propagation environment in Busan into ETRI model application about 지상파 DMB service. It takes to be simulated in Busan area around the mountains area and high building. So it measures the electric field strength in standards. Distribution pattern are similar with mutually in the 이론 and real measurement. Even areas are almost the same, but urban areas and mountains are different with mutually. Therefore, we conclude that ETRI propagation model and theoretical modeling in a free space in Busan area is not suitable.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.05a
• /
• pp.284-287
• /
• 2022

In order to respond to the complexity and uncertainty of water management due to the climate crisis, K-water established a digital twin water management platform based on our experience in operating ICT infrastructure such as hydrological data sensing and high-quality data management and water management capabilities. In this platform, data from related organizations and real-time observation data in the basin are displayed on 3D topographic domain. Also it is configured to support optimal decision-making through simulation for various situations, displaying and analyzing results, and feedback on them. It is completed to establish the platform for Sunjim river basin. Based on this technologies and experience, K-water is planning to expand this digital twin to 5 major rivers in Korea. Through this, it plans to build comprehensive decision-making system for efficient water management considering various conditions in entire basin. Also it aims to create a new water industrial ecosystem and contribute to secure technological competitiveness cooperating with private companies.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.26 no.1
• /
• pp.73-83
• /
• 2008

For spatial analysis and decision-making based on territorial and urban information, technologies on 3D GIS with digital image data and photo-realistic 3D image models to visualize 3D modeling are being rapidly developed. Currently, satellite images, aerial images and aerial LiDAR data are mostly used to build 3D models and textures from oblique aerial photographs or terrestrial photographs are used to create 3D image models. However, we are in need of quality 3D image models as current models cannot express topographic and features most elaborately and realistically. Thus, this study analyzed techniques to use aerial photographs, aerial LiDAR, terrestrial photographs and terrestrial LiDAR to create a 3D image model with artificial features and special topographic that emphasize spatial accuracy, delicate depiction and photo-realistic imaging. A 3D image model with spatial accuracy and photographic texture was built to be served via 3D image map services systems on the Internet. As it was necessary to consider intended use and display scale when building 3D image models, in this study, we applied the concept of LoD(Level of Detail) to define 3D image model of buildings in five levels and established the models by following the levels.

• Journal of Digital Convergence
• /
• v.17 no.12
• /
• pp.191-196
• /
• 2019

The development of open-pit mines leads to large-area topographical changes in highland forests and can lead to severe deterioration of forests, requiring continuous monitoring. The drone photogrammetry is performed at a lower altitude than the existing manned aerial photogrammetry, and thus has a relatively high accuracy. The purpose of this study is to construct spatial information of large open pit mine using drone photogrammetry and to evaluate the accuracy and utilization of the results. The accuracy of the drone photogrammetric results was 0.018 ~ 0.063m in the horizontal direction and 0.027m ~ 0.088m in the vertical direction. These results satisfy the permissible accuracy of 1: 1,000 digital topographic map and it can be used for open mine monitoring. The geospatial information of the open pit mine can be used in various ways, and it can be used to monitor the quantitative change of a specific area for time series change through data management by periodic data acquisition. If drone photogrammetry is applied to open-pit mine monitoring in the future, work time and cost can be greatly reduced compared to the conventional GNSS or total station method, and the work efficiency can be greatly improved because more visible data can be generated.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.32 no.3
• /
• pp.213-220
• /
• 2014

This is the study to conduct the topographical analysis using the orthophotographic data from the waypoint flight using the UAV and constructed the system required for the automatic waypoint flight using the multicopter.. The results of the waypoint photographing are as follows. First, result of the waypoint flight over the area of 9.3ha, take time photogrammetry took 40 minutes in total. The multicopter have maintained the certain flight altitude and a constant speed that the accurate photographing was conducted over the waypoint determined by the ground station. Then, the effect of the photogrammetry was checked. Second, attached a digital camera to the multicopter which is lightweight and low in cost compared to the general photogrammetric unmanned airplane and then used it to check its mobility and economy. In addition, the matching of the photo data, and production of DEM and DXF files made it possible to analyze the topography. Third, produced the high resolution orthophoto(2cm) for the inside of the river and found out that the analysis is possible for the changes in vegetation and topography around the river. Fourth, It would be used for the more in-depth research on landscape analysis such as terrain analysis and visibility analysis. This method may be widely used to analyze the various terrains in cities and rivers. It can also be used for the landscape control such as cultural remains and tourist sites as well as the control of the cultural and historical resources such as the visibility analysis for the construction of DSM.