• Journal of the Korean Association of Geographic Information Studies
• /
• v.27 no.3
• /
• pp.1-13
• /
• 2024

This paper proposes a cost-effective system design and user-friendly approach for the key technological elements necessary to configure an autonomous mobile robot. To implement a high-precision positioning system using an autonomous mobile robot, we established a Linux-based VRS (virtual reference station)-RTK (real-time kinematic) GNSS (global navigation satellite system) system with NTRIP (Network Transport of RTCM via Internet Protocol) client functionality. Notably, we reduced the construction cost of the GNSS positioning system by performing dynamic location analysis of the established system, without utilizing an RTK replay system. Dynamic location analysis involves sampling each point during the trajectory following of the autonomous mobile robot and comparing the location precision with ground-truth points. The proposed system ensures high positioning performance with fast sampling times and suggests a GPS waypoint system for user convenience. The centimeter-level precision GNSS information is provided at a 30Hz sampling rate, and the dead reckoning function ensures valid information even when passing through tall buildings and dense forests. The horizontal position error measured through the proposed system is 6.7cm, demonstrating a highly precise dynamic location measurement error within 10cm. The VRS network-RTK Linux system, which provides precise dynamic location information at a high sampling rate, supports a GPS waypoint planner function for user convenience, enabling easy destination setting based on GPS information.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.3
• /
• pp.1293-1297
• /
• 2016

Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern and northern regions. Database of population at risk are need required for monitoring, surveillance, home health care, and home visit. Therefore, this study aimed to develop a geographic information system (GIS) database and Google map of the population at risk of CCA in Mueang Yang district, Nakhon Ratchasima province, northeastern Thailand during June to October 2015. Populations at risk were screened using the Korat CCA verbal screening test (KCVST). Software included Microsoft Excel, ArcGIS, and Google Maps. The secondary data included the point of villages, sub-district boundaries, district boundaries, point of hospital in Mueang Yang district, used for created the spatial databese. The populations at risk for CCA and opisthorchiasis were used to create an arttribute database. Data were tranfered to WGS84 UTM ZONE 48. After the conversion, all of the data were imported into Google Earth using online web pages www.earthpoint.us. Some 222 from a 4,800 population at risk for CCA constituted a high risk group. Geo-visual display available at following www.google.com/maps/d/u/0/edit?mid=zPxtcHv_iDLo.kvPpxl5mAs90&hl=th. Geo-visual display 5 layers including: layer 1, village location and number of the population at risk for CCA; layer 2, sub-district health promotion hospital in Mueang Yang district and number of opisthorchiasis; layer 3, sub-district district and the number of population at risk for CCA; layer 4, district hospital and the number of population at risk for CCA and number of opisthorchiasis; and layer 5, district and the number of population at risk for CCA and number of opisthorchiasis. This GIS database and Google map production process is suitable for further monitoring, surveillance, and home health care for CCA sufferers.

• Economic and Environmental Geology
• /
• v.54 no.6
• /
• pp.743-752
• /
• 2021

The three-dimensional distribution of the fault was evaluated using gravity field interpretation such as curvature analysis and Euler deconvolution in the Seoul-Gyeonggi region where the Chugaryeong fault zone was developed. In addition, earthquakes that occurred after 2000 and the location of faults were compared. In Bouguer anomaly of Chugaryeong faults, the Pocheon Fault is an approximately 100 km fault that is extended from the northern part of Gyeonggi Province to the west coast through the central part of Seoul. Considering the frequency of epicenters is high, there is a possibility of an active fault. The Wangsukcheon Fault is divided into the northeast and southwest parts of Seoul, but it shows that the fault is connected underground in the bouguer anomaly. The magnitude 3.0 earthquake that occurred in Siheung city in 2010 occurred in an anticipated fault (aF) that developed in the north-south direction. In the western region of the Dongducheon Fault (≒5,500 m), the density boundary of the rock mass is deeper than that in the eastern region (≒4,000 m), suggesting that the tectonic movements of the western and eastern regions of the Dongducheon Fault is different. The maximum depth of the fracture zone developed in the Dongducheon Fault is about 6,500 m, and it is the deepest in the research area. It is estimated that the fracture zone extends to a depth of about 6,000 m for the Pocheon Fault, about 5,000 m for the Wangsukcheon Fault, and about 6,000 m for the Gyeonggang Fault.

• Ecology and Resilient Infrastructure
• /
• v.9 no.4
• /
• pp.282-289
• /
• 2022

Analyzing the impact of climate change on the Korean Peninsula on the forest ecosystem is important for the management of subtropical forest bioresources. In this study, we collected location data and bioclimatic variables of the warm-temperate woody plant species, Myrica rubra and Cyzygium buxifolium, and applied the MaxEnt model based on the collected data to estimate the potential distribution area. Precipitation and temperature seasonality in the warmest quarter were the main environmental factors that determined the distribution of M. rubra, and the main environmental factors for S. buxifolium were precipitation in the warmest quarter and precipitation in the wettest quarter. The results of the MaxEnt model by administrative district, the M. rubra showed an area increase rate of 4.6 - 17.7% in the SSP2-4.5 climate change scenario and 13.8 - 30.5% in the SSP5-8.5 climate change scenario. S. buxifolium showed area increase rates of 4.8 - 32.2% in the SSP2-4.5 climate change scenario and 12.9 - 48.6% in the SSP5-8.5 climate change scenario. This study is meaningful in establishing a database and identifying future potential distribution areas of warm and subtropical plants by applying climate change scenarios.

• Journal of the Society of Disaster Information
• /
• v.12 no.2
• /
• pp.181-188
• /
• 2016

Database construction of basic elements for displaying CCTV informations(the location, direction, distance, maximum distance, Tele mode angle view, Wide mode angle view, etc.) is conducted by complete survey about CCTV information in model area. Automatic mapping algorithm is suggested to schematize and visualize it on the basic of the investigated CCTV informations. In the result, the CCTV locations in partial areas are duplicated on about 11 percents. Duplicated ones among twelve CCTVs are total five. If the redesign of CCTV location and direction by displaying the CCTV informations based on the suggested algorithm is performed, it can be used as scientific explanations.

• Spatial Information Research
• /
• v.19 no.1
• /
• pp.117-126
• /
• 2011

Recently, AR applications provide location-based spatial information by GPS. Also, the spatial information is displayed by the angle of the camera. So far, traditional spatial indexes in spatial database field retrieve and filter spatial information by the minimum bounding rectangle (MBR) algorithm.(ex. R-tree) MBR strategy is a useful technique in the geographic information systems and location based services. But MBR technique doesn't reflect the characteristics of spatial queries in AR. Spatial queries of AR applications have high possibility of the dead space area between MBRs of non-leaf node and query area. We propose triangle node filtering algorithm that improved efficiency of spatial retrieval used the triangle node filtering techniques by exclusion the dead space. In this paper, the proposed algorithm has been implemented on PostgreSQL/PostGIS. Experimental results show the spatial retrieval that using the proposed algorithm better performance than the spatial retrieval that of the minimum bounding rectangle algorithm.

• Smart Media Journal
• /
• v.5 no.2
• /
• pp.42-50
• /
• 2016

In case of a emergency situation or a natural disaster, a warning notification system is an essential tool to notify at-risk people in advance and provide them useful information to survive the event. Although some systems have been proposed such as emergency alert system using android, SMS, or P2P overlay network, these works mainly focus on a reliable message distribution methods. In this paper, we proposed a novel design and implementation of a personalized warning notification system to help inform not only the at-risk people but also their family and friends about the coming disaster as well as escape plan and survival information. The system consists of three main modules: the user selection module, the knowledge based message generator, and message distribution modules. The user selection module collects the list of people involved in the event and sorts them based on their level of involvement (their location, working position and social relationships). The knowledge based message generator provides each person with a personalized message that is concise and contains only the necessary information for the particular person based on their working position and their involvement in the event. The message distribution module will then find a best path for sending the personalized messages based on trustiness of locations since network failures may exist in a disaster event. Additionally, the system also have a comprehensive database and an interactive web interface for both user and system administrator. For evaluation, the system was implemented and demonstrated successfully with a building on fire scenario.

• Journal of Korea Water Resources Association
• /
• v.40 no.12
• /
• pp.985-994
• /
• 2007

Small hydropower is the one of the cleanest one among new and renewable energy with less green house gas emissions. Recently, the necessity of developing small hydropower is emerging since its remaining potential resources in this country are abundant. However, a survey or research on the small hydropower development has been hardly performed since the 1990#s. These circumstances encourages a systematic approach for the small hydropower development. The purpose of this study is to propose a methodology of the location analysis for developing small hydropower. To this end, constraint and location criteria with weights are established and quantification method of each factor is presented. Especially, the analysis procedure is established on the basis of GSIS. Also the study focus on raising the objectivity and precision of analysis by developing system model with automatic search. The proposed methodology is applied to Bochung stream in Keum Riverbasin. The result selects the four and two locations of dam type and run-of-river type respectively. This study will be beneficial to the future activation of small hydropower development as a fundamental work.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.149-152
• /
• 2007

The horizontal geo-location accuracy of KOMPSAT-2, without GCPs (Ground Control Points) is 80 meters CE90 for monoscopic image of up to 26 degrees off-nadir angle, after processing including POD (Precise Orbit Determination), PAD(Precise Attitude Determination) and AOCS (Attitude and Orbit Control Subsystem) sensor calibration. In case of multiple stereo images, without GCPs, the vertical geometric accuracy is less than 22.4 meters LE 90 and the horizontal geometric accuracy is less than 25.4 meters. There are two types of sensor model for KOMPSAT-2, direct sensor model and Rational Function Model (RFM). In general, a sensor model relates object coordinates to image coordinates The major objective of this investigation is to check and verify the geometrical performance when initial KOMPSAT-2 images are employed and briefly introduce the sensor model of KOMPSAT-2.

• ETRI Journal
• /
• v.22 no.4
• /
• pp.32-39
• /
• 2000

In low earth orbit (LEO) satellite communication systems, more severe phase distortion due to Doppler shift is frequently detected in the received signal than in cases of geostationary earth orbit (GEO) satellite systems or terrestrial mobile systems. Therefore, an estimation of Doppler shift would be one of the most important factors to enhance performance of LEO satellite communication system. In this paper, a new adaptive Doppler compensation scheme using location information of a user terminal and satellite, as well as a weighting factor for the reduction of prediction error is proposed. The prediction performance of the proposed scheme is simulated in terms of the prediction accuracy and the cumulative density function of the prediction error, with considering the offset variation range of the initial input parameters in LEO satellite system. The simulation results showed that the proposed adaptive compensation algorithm has the better performance accuracy than Ali's method. From the simulation results, it is concluded the adaptive compensation algorithm is the most applicable method that can be applied to LEO satellite systems of a range of altitude between 1,000 km and 2,000 km for the general error tolerance level, M = 250 Hz.