• Korean Journal of Geomatics
• /
• v.2 no.2
• /
• pp.123-130
• /
• 2002

LiDAR (Light Detection And Ranging) system has a profound impact on geoinformatics. The laser mapping system is now recognized as being a viable system to produce the digital surface model rapidly and efficiently. Indeed the number of its applications and users has grown at a surprising rate in recent years. Interest is now focused on the reconstruction of buildings in urban areas from LiDAR data. Although with present technology objects can be extracted and reconstructed automatically using LiDAR data, the quality issue of the results is still major concern in terms of geometric accuracy. It would be enormously beneficial to the geoinformatics industry if geometrically accurate modeling of topographic surface including man-made objects could be produced automatically. The objectives of this study are to reconstruct buildings using airborne LiDAR data and to evaluate accuracy of the result. In these regards, firstly systematic errors involved with ALS (Airborne Laser Scanning) system are introduced. Secondly, the overall LiDAR data quality was estimated based on the ground check points, then classifying the laser points was performed. In this study, buildings were reconstructed from the classified as building laser point clouds. The most likely planar surfaces were estimated by the least-square method using the laser points classified as being planes. Intersecting lines of the planes were then computed and these were defined as the building boundaries. Finally, quality of the reconstructed building was evaluated.

• Journal of Korean Society for Geospatial Information Science
• /
• v.11 no.1 s.24
• /
• pp.61-69
• /
• 2003

The study is the open area keeping a few visible satellites and the urban area covered with the high building, an electric pole were chosen for evaluation of accuracy of satellite positioning. First, suggest the validity of RTK-GPS, RTK-GPS/GLONASS and compared the accuracy with that of the classical surveying method. As a result. In urban area, in case of real time kinematic positioning when compare between the method combined by GPS/GLONASS and by GPS alone the result of GPS/GLONASS - combination more excellent. And in open ana positioning combined GPS/GLONASS was more excellent than GPS alone in both real time differential and real time kinematic. So, RTK-GPS, RTK-GPS/GLONASS contribute to the digital mapping of Basic map and the existed map necessary for the building of PBLIS to the computerization of cadastral map in the effectiveness in time and in cost and hereafter the combined GPS/TS is expected to contribute to the development of NGIS, Re-investigation of a land register, the execution drawing on site.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.7 no.4
• /
• pp.15-23
• /
• 2004

In order to utilize remote sensed images effectively, it is necessary to correct geometric distortion. Geometric correction is a critical step to remove geometric distortions in satellite images. For geometric correction, Ground Control Points (GCPs) have to be chosen carefully to guarantee the quality of geocoded satellite images, digital maps, GPS surveying or other data. Traditional approach to geometric correction used GCPs requires substantial human operations. Also that is necessary much time and manpower. In this paper, we presented an on-line automatic geometric correction by constructing GCP Chip database. The Proposed on-line automatic geometric correction system is consists of four part. Input image, control the GCP Chip, revision of selected GCP, and output setting part. In conclusion, developed system reduced the processing time and energy for tedious manual geometric correction and promoted usage of Landsat imagery.

• Korean Journal of Geomatics
• /
• v.2 no.1
• /
• pp.47-55
• /
• 2002

Remote sensing is the science and art of obtaining information about an object, area or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under investigation./sup 1)/ EOC (Electro -Optical Camera) sensor loaded on the KOMPSAT-1 (Korea Multi- Purpose Satellite-1) performs the earth remote sensing operation. EOC can get high-resolution images of ground distance 6.6m during photographing; it is possible to get a tilt image by tilting satellite body up to 45 degrees at maximum. Accordingly, the device developed in this study enables to obtain images by photographing one pair of tilt image for the same point from two different planes. KOMPSAT-1 aims to obtain a Korean map with a scale of 1:25,000 with high resolution. The KOMPSAT-1 developed automated feature extraction system based on stereo satellite image. It overcomes the limitations of sensor and difficulties associated with preprocessing quite effectively. In case of using 6, 7 and 9 ground control points, which are evenly spread in image, with 95% of reliability for horizontal and vertical position, 3-dimensional positioning was available with accuracy of 6.0752m and 9.8274m. Therefore, less than l0m of design accuracy in KOMPSAT-1 was achieved. Also the ground position error of ortho-image, with reliability of 95%, is 17.568m. And elevation error showing 36.82m was enhanced. The reason why elevation accuracy was not good compared with the positioning accuracy used stereo image was analyzed as a problem of image matching system. Ortho-image system is advantageous if accurate altitude and production of digital elevation model are desired. The Korean map drawn on a scale of 1: 25,000 by using the new technique of KOMPSAT-1 EOC image adopted in the present study produces accurate result compared to existing mapping techniques involving high costs with less efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.1
• /
• pp.107-112
• /
• 2020

Recently, as the field of use of drones is diversified, it is actively used not only for surveying but also for search and rescue work. In these applications it is very important to know the location of the target or the location of the UAV. This paper proposes a target detection method using images taken from drones. The proposed method calculates the latitude and longitude information of the target by finding the location of the target by comparing it with the image to find the image taken by the drone. The exact latitude and longitude information of the target is calculated by calculating the actual distance corresponding to the distance of the image image using the characteristics of the pinhole camera. The proposed method through the actual experiment confirmed that the latitude and longitude of the target was accurately identified.

• Journal of Information Technology Applications and Management
• /
• v.27 no.6
• /
• pp.197-224
• /
• 2020

Mobile games have become one of the most important driving forces of the game industry. We focus on the continuous intention to use Chinese mobile games from the perspective of experiential marketing and network externalities. We integrate user experience, network externalities and flow theory into expectation confirmation model and explore the influencing factors of continuous usage intention of Chinese mobile game and propose a research model. Game experience, service experience, perceived enjoyment, social interaction, challenge, perceived number of users and perceived number of peers were employed as independent variables, while flow, perceived value and satisfaction as mediating variables and continuous intention as the dependent variable. After surveying 426 samples, the model is tested with structural equation model. The results reveal that perceived enjoyment significantly positively influences perceived value, flow, satisfaction, and continuous intention. The greater the enjoyment of the game, the greater the satisfaction of the game and the greater the willingness to use it continuously. Game experience has a significant direct effect on continuous intention, which indicates that a better game experience can retain more users. Service experience and perceive number of peers positively influence satisfaction. Another finding is that social interaction and perceived number of users positively influence perceived value and flow, which indicate that social attributes are critical roles for retaining users. Game challenge also positively influences flow. The proper level of challenge is more likely to cause users to enter the state of flow. Flow indirectly influences continuous usage intention through the satisfaction of the game, which indicates that satisfaction is driven by flow experience and further retaining users. Empirical results implied that mobile game companies need to focus on improving user experience, expectation satisfaction and extending network externalities to improve the continuous intention of using mobile game.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.12
• /
• pp.1942-1948
• /
• 2021

The cadastre in Korea was established with the outdated technology of the Japanese colonial period, and thus currently 15% of the Korea domestic land does not match the cadastral map. Accordingly, the government has been establishing the Korean cadastre under the name of 'Cadastral Re-investigation Project' and is changing the origin of the survey to the world geodetic system. Assuming that the project is completed, we propose a drone boundary survey method that can be used to easily survey using the exact digital cadastral information. The developed mobile GCS application can control the drone and acquire the boundary point coordinates recorded in the cadastre, and the drone automatically flies to mark the boundary points. The developed prototype of drone made a tour along the 6 boundary points in 2 minutes.

• Journal of Conservation Science
• /
• v.38 no.4
• /
• pp.347-359
• /
• 2022

Gongsanseong Fortress was registered of a World Heritage Site in 2015 as a representative cultural heritage from the Woongjin Baekje period, and it has been used throughout the entire period from Baekje Kingdom to the Joseon Dynasty. Within Gongsanseong Fortress, the area around Ssangsujeong is presumed the site of royal palace of the Woongjin Baekje. Also, the excavated culture layers of the Baekje Kingdom, the Unified Silla period, and the Joseon Dynasty were confirmed. In this study, paleotopography was modeled by digitally converting the elevation data obtained through surveying the excavation process, and the use of the topography in the Ssangsujeong area was considered by examining the variations in the topography according to the periods. As a result, the topography of the slope around the peak changed by periods, and the topography did not change on the flat land. The topography between the Baekje Kingdom and the Unified Silla period appeared to be almost identical, and it seems that the space of the Baekje period was maintained as it is. Also, during the Joseon Dynasty, it is confirmed that flat surfaces in the previous period were used. However, sediments on the slopes flowed down, reducing the area of the flatland, and architectural techniques that could utilize the natural topography of the changed slope were applied to interpret it as having a different topography from the previous period. In order to model and interpret the paleotopography, excavation data, geological and topographic analysis, and digital data must be secured. It is expected that location conditions and ancient human life can be identified if the analysis technique in the study is applied to other archaeological sites in the future.

• Geomechanics and Engineering
• /
• v.39 no.4
• /
• pp.385-396
• /
• 2024

With the recent development of satellite, aerial, and remote sensing technologies, it is easy to produce landslide inventory maps over a large area. In this study, the object-based framework was designed to address the limitations inherent in the pixel-based deep learning (DL) methodology. This framework explores the potential of combining Sentinel-2 MultiSpectral Instrument (MSI) satellite imagery and digital elevation models (DEMs) to enhance shallow landslide mapping across diverse terrains comprehensively. The study area for analysis and verification was selected as Jucheon-myeon, Namwon-si, and Jeollabuk-do, where significant large-scale landslides and slope failures occurred in 2020. As a result, the application of this framework led to the classification of 68 candidate sites spanning an area of 0.5 hectares or more. Site surveying was conducted on 20 random sites with a 1ha or more scale. Furthermore, six sites were selected where satellite imagery could discern the damaged areas. At these locations, the damaged area estimated by the framework was compared with the actual observed damaged area to assess accuracy. These rapid and cost-effective landslide mapping techniques can accurately estimate the location and extent of landslides and enhance the precision of sensitivity models and land management strategies.

• Journal of Digital Convergence
• /
• v.10 no.5
• /
• pp.105-116
• /
• 2012

This thesis is surveying the notions and the countermeasures of the farmers, who produce environmental-friendly crops, on a market and buyers. It ultimately tries to find out ways to increase the sale and the consumption of environmental-friendly crops from the side of the farmers. In chapter 2, analyzing the reality of consuming environmental-friendly crops and consumers inclinations. Also, on the basis of this, in chapter 3, I demonstrate how environmental-friendly producers countermeasures for the consumers are. I try to analyze the trust of the consumer buying environmental-friendly crops, which have been pointed out as a decisive factor for environmental-friendly crops by a lot of researchers, and analyze producers methods dealing with consumers approach to consume environmental-friendly crops. Regarding ways of the reconsideration about the trust, I have shown the problems about the quality authentication, forming consumers trust, and the ways of the consumer management. For the channel and method of the sale I have scrutinized not only a farmers notion about an internet homepage and his or her use but also producers principal sales route, cognition, and correspondence about it. Finally, I have examined the counter plans of the producer to increase sale and to facilitate consumption.