• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.315-319
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• 2007

This paper presents a algorithm, what is able to recognize 4 different continuous human motion using a single stationary camera as input. For the first step, we acquire images from a camera. To enhance the image, we perform preprocessing which deals with removing noise using median filter, thresholding. And then morphological operations are performed to remove which small blobs and eliminates small holes. At the forth step, blobs are analysed to extracts for foreground region. Then, motions are predicted from these images by using optical flow technique, and the predicted motion data are refined by comparing our cardboard models so as to judge behavior pattern.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1558-1563
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• 2004

A measurement technique for the void fraction and the bubble dynamics in gas-liquid two-phase flows has been proposed using a time-resolved two-phase PIV system. For the three-dimensional evaluation of the bubble information, both the images from the front and side views are simultaneously recorded into a high speed CCD camera by reflecting the side image into the front view with the help of a $45^{\circ}$ oriented mirror. Then, a stereo-matching technique is applied to calculate the void fraction, bubble size and shape. To obtain the rising bubble velocities, the 2-frame PTV method was applied. Consequently, the present technique shows good feasibility for the measurements of the volume fractions, mean diameters, aspect ratios and velocities of the bubbles at the three-dimensional point of view.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.169-172
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• 2002

A vision sensor measure range data using laser light source. This sensor generally use patterned laser which shaped single line. But this vision sensor cannot satisfy new trend which feeds foster and more precise processing. The sensor's sampling rate increases as reduced image processing time. However, the sampling rate can not over 30fps, because a camera has mechanical sampling limit. If we use multi line laser pattern, we will measure multi range data in one image. In the case of using same sampling rate camera, number of 2D range data profile in one second is directly proportional to laser line's number. For example, the vision sensor using 5 laser lines can sample 150 profiles per second in best condition.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.210-217
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• 2000

Noncontact measuring methodology of 3-dimensional profile using CCD camera are very attractive because of it's high measuring speed and it's high sensitivity. Especially when projecting a grid pattern over the object, the captured image have 3 dimensional information of the object. Projection moire extract 3-D information with another grid pattern in front of CCD camera. However phase measuring profilometry(PMP) obtain similar results without additional grid pattern. In this paper, the projection moire are compared with the PMP mathematically, and it is shown that PMP can generate moire image with simple mathematical computations. Experimental works are also carried out showing the same results. It is shown that using a single gird pattern, moire image can be obtained directly without any mathematical operation when some conditions are satisfied.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.201-207
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• 1998

It was theoretically calculated the image position and size using matrix to obtain the reflection pattern for eye's cornea and crystalline, and made system to measure the reflection pattern by three light sources and a reflex camera. Hyperopia and myopia were measured by reflect pattern using single light source at retina, and cornea and curvature of crystalline were measured by the reflection pattern using double light sources.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.57-64
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• 1999

Initial flame development and propagation were visualized under the new ignition system developed to estimate the effects of ignition characteristics on the engine performance in a port injection SI engine. Effects of intake air flow characteristics were also investigated by three different kinds of the swirl control valve. Experiments were performed in an optical single cylinder engine modified form a commercial engine. Flame images were captured through the quartz window mounted in the piston by the high speed video camera and analyzed to compare initial flame development. Results show that IMEP tends to rise slightly as the ignition duration gets longer. The direction of flame propagation is decisively governed by the in-cylinder flow motion. Every flame grows toward the exhaust valve forming a kind of turbulent flame. Initial flame propaagation characteristics are very similar to ones analyzed form pressure data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.291-298
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• 2004

The observations of rapid motion of bubbles under water for approximately 50 ms or less in high-magnetic fields of 10 T have been carried out successfully for the first time. The observation system constructed is composed of a high-speed video camera, a telescope, a cryostat with a split-type superconducting magnet, a light source, a mirror and a transparent sample cell. Using this system, the influence of magnetic field on the path and shape of single bubbles of O$_2$ (paramagnetism) and N$_2$ (diamagnetism) has been examined carefully. Experimental values describing the path are in good agreement with theoretical values calculated on the basis of the magneto-Archimedes effect, despite the effect of magnetism on the bubble. However, no effect of magnetism on the shape of the bubble is observed. In addition, the influence of magnetic field on drag coefficient of the bubble is discussed.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.566-571
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• 1994

This paper presents in image-based visual servo control scheme for tracking a workpiece with a hand-eye coordinated robotic system using the fuzzy-neural-network. The goal is to control the relative position and orientation between the end-effector and a moving workpiece using a single camera mounted on the end-effector of robot manipulator. We developed a fuzzy-neural-network that consists of a network-model fuzzy system and supervised learning rules. Fuzzy-neural-network is applied to approximate the nonlinear mapping which transforms the features and theire change into the desired camera motion. In addition a control strategy for real-time relative motion control based on this approximation is presented. Computer simulation results are illustrated to show the effectiveness of the fuzzy-neural-network method for visual servoing of robot manipulator.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.1
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• pp.1-8
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• 2002

It has been integrated into several navigation systems. This paper shows that system recognizes difficult indoor roads without any specific marks such as painted guide line or tape. In this method the robot navigates with visual sensors, which uses visual information to navigate itself along the read. The Neural Network System was used to learn driving pattern and decide where to move. In this paper, I will present a vision-based process for AMR(Autonomous Mobile Robot) that is able to navigate on the indoor read with simple computation. We used a single USB-type web camera to construct smaller and cheaper navigation system instead of expensive CCD camera.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.394-398
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• 1992

The measurable speed range of the self-mixing type semiconductor laser range finder has been greatly improved by employing a new processing circuit. Using this range finder as an external finder of a single lens reflex (SLR) autofocus (AF) camera, some clear photographs of an object moving at a medium speed of 20 mm/s is obtained.