• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.6
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• pp.1025-1032
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• 2022

In this paper, the TDMA-based PoE wireless multi-IP camera transmission system using wireless communication technology is developed to reduce the burden of construction costs caused by the existing wired-based CCTV surveillance system and IP camera system. It intends to design and implement the long-distance wireless transmission technology of video. The transmission/reception prototype of the line IP transmission system and the wireless multi-IP camera transmission terminal and image acquisition device (SB-200) for the proposed related technology were described.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.157-160
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• 2008

A realization for moving object detecting and tracking system in two dimensional plane using stereo line CCDs and lighting source is presented in this paper. Instead of processing camera images directly, two line CCD sensor and input line image is used to measure two dimensional distance by comparing the brightness on line CCDs. The algorithms are used the moving object tracking and coordinate converting method. To ensure the effective detection of moving path, a detection algorithm to evaluate the reliability of each measured distance is developed. The realized system results are that the performance of moving object recognizing shows 5mm resolution and mean error is 1.89%, and enables to track a moving path of object per 100ms period.

• Journal of Korea Multimedia Society
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• v.15 no.8
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• pp.1004-1016
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• 2012

This paper proposes a mobile augmented reality system to provide detail information of the products using QR code included in them. In the proposed system, we perform the estimation of the camera pose using both of marker-based and markerless-based methods. If the camera can see the QR code, we perform the estimation of the camera pose using the set of rectangles in the QR code. However, if the QR code is out of sight, we perform the estimation of the camera pose based homography between consecutive frames. Moreover, the content of the augmented reality in the proposed system is made by using meta-data. Therefore, the user can make contents of various scenario using only meta-data file without modification of our system. Especially, our system maintains the contents as newly updated state by the on-line server. Thus, it can reduce the unnecessary update of the program.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.6
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• pp.852-859
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• 2009

Normally, to extract the defect in TFT-LCD inspection system, the image is obtained by using line scan camera or area scan camera which is achieved by CCD or CMOS sensor. Because of the limited dynamic range of CCD or CMOS sensor as well as the effect of the illumination, these images are frequently degraded and the important features are hard to decern by a human viewer. In order to overcome this problem, the feature vectors in the image are obtained by using the average intensity difference between defect and background based on the weber's law and the standard deviation of the background region. The defect detection method uses non-linear SVM (Supports Vector Machine) method using the extracted feature vectors. The experiment results show that the proposed method yields better performance of defect classification methods over conveniently method.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.16 no.3
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• pp.41-48
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• 2012

Objectives: The aims of this study are to design a optimized mechanical structure of digital tongue imaging system (DTIS) equipped with LEDs in aspects of object distance and camera angle of coverage. Methods and Results: We tried to find optimized object distance while recording a rectangular object of common tongue size. In case object distance is 22 cm or less, edge of the rectangle was not taken beyond the shooting range. In contrast, if object distance is 40 cm or more, the rectangle image was too small. Therefore when considering the variation of subjects, we selected distance of 35-40 cm as appropriate object distance for the DTIS. We also tried to find optimized angle between camera view axis and horizontal line. We photographed from the side of the face of 7 adults with exposed tongue. We drew an exposed tongue lines to connect the tongue tip points and the tongue root points by using the photos acquired from the side faces. And then we calculated the tongue exposure angles between the vertical line and the exposed tongue lines. Mean tongue exposure angle was $28.3^{\circ}$ when tongue was lightly exposed and $13.3^{\circ}$ when maximally. So we determined $73^{\circ}$ as appropriate slope angle of part in contact with face of the DTIS and by considering that the standard variation was great, we designed control gears to adjust the slope of the camera view axis and to regulate the object distance. Conclusions: We designed a optimized mechanical structure in object distance and slope angle of part in contact with face of the DTIS.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1189-1198
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• 2021

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.400-402
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• 2019

The electric point machine, which is used for the control of the turnout used to change the track of the train, is very important in the railway system. Various wired and wireless real-time monitoring systems are used to check the status of the point machine, but there is a possibility of malfunction due to sensor or network error. In this paper, a redundant monitoring system was designed that incorporates the point machine monitoring system and the CCTV camera control system to double check the operation of the point machine. In the point machine monitoring system, the operating state of the railway converter is monitored, alarmed and transmitted over the network. The CCTV camera control system, which received this information, was required to record the status of the turnout and the point machine in question and send it to the administrator. The manager of the railway line can check the conversion status of the railway through the monitoring screen for the railway line switcher first, and then confirm the switching status directly through the CCTV camera image, thereby improving the reliability of the point machine operation. It will also enable the safe and efficient operation of personnel for management. It is expected to contribute to preventing a derailment caused by a malfunction of the point machine.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.63-73
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• 2016

PURPOSES : The objective of this study was to analyze variations in the vehicle driving behavior characteristics on signalized intersections according to the use of traffic enforcement camera (red light camera). METHODS : In order to analyze the driving behavior characteristics on signalized intersections when red light camera are installed, the target sites for investigation were selected depending on whether the red light camera is installed and accident rates increased after the installation. In particular, to analyze the characteristics of dilemma zones in signalized intersections, approach speed and deceleration speed of 3 type vehicles (passing vehicles during a yellow light, stopping at a yellow light, passing vehicles during a green light) were examined. Based on these data, the starting point, ending point, and distance of the dilemma zones were calculated. Also, the locations of increased traffic accidents and decreased accidents after the installation of the equipment were distinguished when analyzing the traffic accident characteristics. RESULTS : Analysis results revealed that there was a tendency for the dilemma zone distance to decrease after the installation of equipment(red light camera) in most sites. This tendency was found to be due to the decrease in the approaching speed of vehicles at intersections after the installation of equipment, resulting in the starting and ending points of dilemma zone to become closer to the stop line. Moreover, analysis showed that the number of traffic accidents decreased for most intersections after the installation of equipment and safety of the intersections increased somewhat. CONCLUSIONS : In general, installation of equipment(red light camera) caused the intersections approaching speed and dilemma zone distance to decrease. Decision-making is difficult for drivers in the dilemma zone, so the decrease in the dilemma zone distance implies an improvement in traffic safety. Furthermore, the number of accidents within intersections significantly decreased after the equipment was installed, leading to the conclusion that installation of the equipment affected the decrease in traffic accidents.

• Journal of Korea Multimedia Society
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• v.21 no.2
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• pp.181-187
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• 2018

Line-laser beams are used for depth measurement of welding beads along the circumference of a pipe. For this, first we project a line-laser beam on an rotating pipe and take a sequence of images of the beam projected on the pipe using a CCD camera. Second, the projected line laser beam in each image is detected, converted into a thin curve. Finally measure the distance between the thinned curve and an imaginary line. When a line-laser beam is projected to a rough metal surface such as arc welding beads, the beam is severely scattered. This severe scattering makes the thinned curve perturbed. In this paper, we propose a thinning method robust against scattering of line lasers. First, we extract a projected line laser beam region using an adaptive threshold. Second, we model a thinned curve with a spline curve with control points. Next, we adjust the control points to fit the curve to the projected line-laser beam. Finally, we take a weighted mean of thin curves on a sequence of image frames. Experiments shows that the proposed thinning method results in a thinning curve, which is smooth and fit to the projected line-laser beam with small error.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.11
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• pp.1106-1111
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• 2007

The visual inspection method that depends on human's eyes has some problem that a lot of variations happen in examination according to bodily, spiritual state of the checker. We automate remocon inspection process using CCD camera. Our developed inspection system can be used in any remocon production line without the user's big handling. Our inspection system was developed using PC, CCD Camera, Visual C++ for universal work place. The accuracy of proposed system was improved about 3.2[%] than the conventional pattern matching method and the processing time was decreased about 119[ms]. Also we showed that our inspection system is more robust to lighting circumstances.