• Korean Journal of Remote Sensing
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• v.9 no.1
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• pp.37-49
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• 1993

In this research, the WEF AX and APT(Automatic Picture Transmission) data receiving and image processing software using PC/AT called WADIPS(WEFAX and APT Data Integrated Processing System) Software has been developed. The main functions of WADIPS software are follow : 1) Real time receiving and saving to hard disk of WEFAX and APT data 2) B/W(Black and White) and false color display 3) Image enhancement using histogram stretch and color control 4) 2-4 times zooming 5) Hard copy of data using dithering and patterning 6) Animation 7) File management 8) On line help. WADIPS can be used in the offices or persons need real time meteorological information and education offices to teach the image processing technique and general characteristics of meteorological satellites.

• Journal of Information Technology Applications and Management
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• v.28 no.6
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• pp.87-95
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• 2021

Recently interest for air pollution is gradually increasing. However, according to the environmental assessment of air quality, the level of air pollution in the nation is quite serious, and air pollutants measuring facilities are also not enough. In this paper, a secure air pollutants sensor system based low power wireless communication is designed and implemented. The proposed system is composed of three parts: air pollutants measuring sensors module, LoRa-based data transmission module, and monitoring module. In the air pollutants measuring module, the MSP430 board with six big air pollutants measuring sensors are used. The air pollutants sensing data is transmitted to the control server in the monitoring system using LoRa transmission module. The received sensing data is stored in the database of the monitoring system, and visualized in real-time on the map of the sensor locations. The implemented air pollutant sensor system can be used for measuring the level of air quality conveniently in our daily lives.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1058-1060
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• 2003

A ground control point (GCP) is a point on the surface of Earth where image coord inates and map coordinates can be identified. The GCP is useful for the geometric correction of systematic and unsystematic errors usually contained in a remotely sensed data. Especially in case of synthetic aperture radar (SAR) data, it has serious geometric distortions caused by inherent side looking geometry. In addition, SAR images are usually severely corrupted by speckle noises so that it is difficult to identify ground control points. We developed a ground point extraction algorithm that has an improved capability. An application of radargrammetry to Daejon area in Korea was studied to acquire the geometric information. For the ground control point extraction algorithm, an ERS SAR data with precise Delft orbit information and rough digital elevation model (DEM) were used. We analyze the accuracy of the results from our algorithm by using digital map and GPS survey data.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.10
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• pp.1051-1056
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• 2014

In this paper, we introduce an intelligent robotic arc welding system which exploits sensors like as LVS (Laser Vision Sensor), Hall effect sensor, voltmeter and so on. The use of industrial robot is saturated because of its own limitation, and one of the major limitations is that industrial robot cannot recognize the environment. Lately, sensor-based environmental awareness research of the industrial robot is performed actively to overcome such limitation, and it can expand application field and improve productivity. We classify the sensor-based intelligent arc welding robot system by the goal and the sensing data. The goals can be categorized into detection of a welding start point, tracking of a welding line and correction of a torch deformation. The Sensing data can be categorized into welding data (i.e. current, voltage and short circuit detection) and displacement data (i.e. distance, position). This paper covers not only the explanation of the each category but also its advantage and limitation.

• Journal of Welding and Joining
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• v.16 no.3
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• pp.129-140
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• 1998

An interface system was developed to offer the welding capability to a robot controller which had not any embedded function for arc welding before, and also an arc sensor algorithm was proposed for weld seam tracking of the welding robot. For the interface system between the robot controller and welding equipments, data communication software and interface connections were composed. The interface system was mae to correspond welding condition, correction data, operation sequence and current status with the robot controller by mutual had shaking and digital signal transfer. Graphic user interface program developed under the environment of windows made it easy to monitor data communication and operation status, and to control welding and sensing sequence. Arc sensing algorithm proposed in this study to compensate torch position error was based on a fuzzy logic with the variables of current difference and current differenced change at torch weaving extremities. The developed interface system could be successfully implemented in between welding equipments and the robot controller, and showed normal status and exact function in data and signal communication between the systems. The whole robot welding system was then examined to verify its welding and seam tracking capabilities in horizontal fillet, vertical fillet, and 3-dimensional fillet weldment. The experiments revealed sound weld bead shapes and also good seam tracing results.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1460-1463
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• 2005

In this paper, analysis of magnetic marker for autonomous vehicle guidance system using 3-axis magnetic sensor propose. Position sensing is an important an estimation system of vehicle position and orientation on magnetic lane, which is a parameter of the steering controller for automated lane following is described. To verify that the magnetic dipole model could be applied to a magnetic unit paved in roadway, the analysis of the data 3-axis magnetic field measured experimentally.

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.551-558
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• 2008

This paper deals with the real-time stable walking for a humanoid robot, ISHURO-II, on uneven terrain. A humanoid robot necessitates achieving posture stabilization since it has basic problems such as structural instability. In this paper, a stabilization algorithm is proposed using the ground reaction forces, which are measured using FSR (Force Sensing Resistor) sensors during walking, and the ground conditions are estimated from these data. From this information the robot selects the proper motion pattern and overcomes ground irregularities effectively. In order to generate the proper reaction under the various ground situations, a fuzzy algorithm is applied in finding the proper angle of the joint. The performance of the proposed algorithm is verified by simulation and walking experiments on a 24-DOFs humanoid robot, ISHURO-II.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.192-197
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• 2003

A virtual vessel traffic control system is introduced to contribute to prevent a marine accident, e.g. ship collision or stranding. from happening. The system that comes from VTS limitaions, consists of both data acquisition by satellite remote sensing and a simulation of traffic environment stress (here, INOUE model used) based on the satellite data. Remotely sensed data cab be used to provide timely and detailed information about the marine safety, including the location, speed and direction of ships, and help us operate vessels safely and efficiently. If in the future, e.g. 5-minute after, environmental stress values that a ship may encounter on a voyage can be available, proper actions can be taken to prevent accidents. It lastly can be shown that JERS satellite data are used to track ships and extract their information.

• Korean Journal of Remote Sensing
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• v.21 no.1
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• pp.73-81
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• 2005

We construct improved geocentric digital elevation model (DEM), estimate tidal dynamics and ice stream velocity over Sulzberger Ice Shelf, West Antarctica employing differential interferograms from 12 ERS tandem mission Synthetic Aperture Radar (SAR) images acquired in austral fall of 1996. Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry profiles acquired in the same season as the SAR scenes in 2004 are used as ground control points (GCPs) for Interferometric SAR (InSAR) DEM generation. 20 additional ICESat profiles acquired in 2003-2004 are then used to assess the accuracy of the DEM. The vertical accuracy of the OEM is estimated by comparing elevations with laser altimetry data from ICESat. The mean height difference between all ICESat data and DEM is -0.57m with a standard deviation of 5.88m. We demonstrate that ICESat elevations can be successfully used as GCPs to improve the accuracy of an InSAR derived DEM. In addition, the magnitude and the direction of tidal changes estimated from interferogram are compared with those predicted tidal differences from four ocean tide models. Tidal deformation measured in InSAR is -16.7cm and it agrees well within 3cm with predicted ones from tide models. Lastly, ice surface velocity is estimated by combining speckle matching technique and InSAR line-of-sight measurement. This study shows that the maximum speed and mean speed are 509 m/yr and 131 m/yr, respectively. Our results can be useful for the mass balance study in this area and sea level change.

• Journal of Digital Contents Society
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• v.15 no.3
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• pp.319-326
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• 2014

IEEE 802.11 WLAN uses CSMA/CA(Carrier Sense Multiple Access/Collision Avoidance) method in MAC(Media Access Control) protocol, and through the carrier sense checks whether other users use the channel during the data transmission to avoid the data collision. Currently, IEEE 802.11 standard recommends the use of a fixed threshold which gives an impact on carrier sensing range. However, the existing scheme using the fixed threshold causes the operation of network to be inefficiency owing to the mobility in MANET(Mobile Ad hoc NETwork). In this paper, we found the better network throughput to be obtained by applying the proposed scheme, which chooses properly the carrier sensing threshold and transmission rate considering SINR(Signal to Interference-plus-Noise Ratio), to the MANET.