• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.519-529
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• 2013

This paper introduces a moving object tracing system using network-connected CCTV and smartphone. In an emergency situation, a smartphone of the reporter gains its GPS information and sends that to the central server. The central server stores received GPS information as a dangerous area in the database and keeps sending the order of tracing the reporter to a network-connected CCTV which can film the reporter. At the same time, the central server sends pictures of the reporter to his or her family and related organization in order to handle the emergency situation as soon as possible. In addition, when a reporter want to know the risk around destination, the central server informs dangerous areas to the reporter by using smart phone application and database of a danger spot.

• Geophysics and Geophysical Exploration
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• v.16 no.4
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• pp.284-292
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• 2013

A stable procedure is presented to attain most probable and unbiased estimate of principal strain, rotation, and dilatation for 2-dimensional geodetic data on triangular network. The proper network size should be chosen carefully, because the errors of these estimates of strain tensor and other associated observables grow inversely proportional to the area of station triangle. As a case study, the deformation observables for the GPS-monitored co-seismic displacement in Korea due to the 2011 Tohoku-Oki earthquake were attained accordingly.

• Journal of Industrial Technology
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• v.36
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• pp.71-76
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• 2016

In this study, we determined the precise coordinates of TBMs (Tidal Bench Marks), which used as the national reference points in coastal area of Korea, using a GPS data analysis SW for the academic and scientific applications, GAMIT/GLOBK. For accurate 3-D positioning of TBM locations, we performed the GPS point surveying according to the national surveying policy and also acquired the GPS data for 48 TBMs located in the western and southern coastal part of Korea. Considering the results of baseline analysis to each observation session obtained from GAMIT module, the baseline analysis was realized to be done precisely because the values of Normalized RMS (NRMS) were mostly less than ${\pm}0.20mm$. Before the network adjustment using GLOBK module, we evaluated the suitability of observations for each session by applying the chi-squared test (${\chi}^2$ test) to the degree of freedom in observed session. An overall distributions of ${\chi}^2$ test were less than 1.0 for all sessions, and the statistical of ${\chi}^2$ test showed the average, 0.267 with minimum and maximum value, 0.063 and 0.653, respectively. Finally, we analyzed the network adjustment for 48 TBMs to reduce the residuals of baseline analysis on each point by connecting with 42 permanent GPS stations in Korea. In the network adjustment procedure, we set up the weighted values of each permanent station to be allocated between 0.9 and 1.14, and also removed the observed points having residual exceeds 4-times of standard deviation ($4{\sigma}$).

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.2
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• pp.139-147
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• 2008

The positioning accuracies tend to deteriorate as the distance between the rover and the reference station increases in the Real-Time Kinematic (RTK) surveys using Global Positioning System (GPS). To solve this problem, the National Geographic Information Institute (NGII) of Korea has installed Virtual Reference System (VRS), which is one of the network-based RTK systems. In this study, we conducted the accuracy tests of the VRS-RTK surveys. We surveyed 50 control points inside the NGII's GPS Continuously Operating Reference Stations (CORS) network using the VRS-RTK system, and compared the results with the published coordinates to verify the positioning accuracies. We also conducted the general RTK surveys at the same control points. The results showed that the positioning accuracy of the VRS-RTK was comparable to that of the general RTK, because the horizontal positioning accuracy was 3.1 cm while that of general RTK was 2.0 cm. Also the vertical positioning accuracy of VRS-RTK was 6.8 cm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2730-2736
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• 2010

Recently, various networks have been introduced in the car of the internal and external sides. These have been integrated by one HMI(Human Machine Interface) to control devices of each network and provide information service. The existing vehicle navigation system, providing GPS based vehicle positioning service, has been included to these integrated networks as a default option. The GPS has been used to the most universal device to provide position information by using satellites' signal. But It is impossible to provide the position information when the GPS can't receive the satellites' signal in the area of tunnel, urban canyon, or forest canopy. Thus, this paper propose and implement the method of measuring vehicle position by using the sensing data of internal CAN network and external Wi-Fi network of the integrated car navigation circumstances when the GPS doesn't work normally. The results obtained by implementation shows the proposed method works well by map matching.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.5
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• pp.889-896
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• 2022

Data required in a wireless sensor network environment requires more accurate figures as technology advances and its complexity increases. However, in the case of operating a large number of sensor nodes in a large area, the balance between the power consumed and the data quality that can be acquired accordingly should be considered for that purpose. In particular, in complex, densely populated urban areas or military operations with specific goals, location data requires increasingly detailed and high accuracy over a wide range. In this paper, we propose a method of mounting a Global Positioning System(: GPS) only on some of the sensor nodes deployed in the wireless sensor network and improving the error of GPS location data measured on that sensor node through Angle of Arrival(: AoA) and Received Signal Strength Indicator(: RSSI).

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.25 no.1
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• pp.15-22
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• 1997

The GPS/levelling geoid calculated from GPS survey that data at 123 bench marks represents an appropriate regional geoid of the southern Korean peninsula. The GPS/levelling geoid fits best to the geoid calculated from the EGM96 geopotential model of degree and order to 360 with RMS difference 0.176 m. The good agreement of the GPS/levelling geoid with the EGM96 geoid suggests that the bench mark network is well established in Korea and the EGM96 geopotential model well represents the gravity field in the southern Korean peninsula.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.2
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• pp.126-133
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• 2010

Due to the deployment of various wireless networks originating from CDMA, GSM, and WLAN, it became very convenient to exchange information from one place to another. As compared with the traditional environments for one-way information distribution based on fixed radio frequency bands, the convenient wireless network environments will bring about many changes in positioning technologies based on global navigation satellites. Among the many changes to come, the reconfigurable receiver network is one of the most attractive concepts since it can be tailored to a specific application area among networked robots, formation flying, bridge monitoring, and traffic monitoring. As an initial study to develop a reconfigurable receiver network, this paper deals with the design and implementation of the key elements of the reconfigurable receiver netowork; server, broadcaster, and client. In the designed receiver network, a sever receives and decodes measurements from a reference receiver installed at a known location, a broadcaster processes and transfers the messages from servers to clients and manages connections with servers and clients, a client receives the messages from the broadcaster and performs differential positioning. A real-time experiment result is demonstrated to validate the functionalities of each network element.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.5
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• pp.465-474
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• 2007

This paper focuses on examining and evaluating results of the Korean Geodetic Datum 2002 (KGD2002) of the national horizontal network adjustment. To this end, 137 geodetic control points were independently observed by GPS technology. After processing all the observations, their results were compared with ones derived by the national network adjustment which was recently performed to determine new KGD 2002 coordinate sets over the national geodetic control points. The comparisons results showed that RMSE was ${\pm}2.7cm$ and ${pm}6.5cm$ in horizontal and vertical component in the case of GPS network, whereas RMSE was ${\pm}3.0cm$, in horizontal component in the case of EDM network.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.197-203
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• 2010

The problem of location awareness in wireless sensor networks where nodes use GPS (Global Positioning System), remains challenging problem, when considering the required large energy consumption during the localization phase. In this paper we designed hardware for GPS based localization and propose a framework, called ELS, to consume low cost energy. In the ELS framework, sensor nodes are equipped with GPS. Because GPS spends large energy for position awareness, conventional localization algorithms cannot use GPS-device. We try to find a solution for efficient energy expenditure of GPS. Finally, we derive optimal transmission power of GPS data and a scheme of localization through experiment and simulation.