• Proceedings of the KSME Conference
• /
• 2002.08a
• /
• pp.507-510
• /
• 2002

An algorithm of 3-D particle image velocimetry(3D-PIV) was developed for the measurement of 3-D velocity Held of complex flows. The measurement system consists of two or three CCD camera and one RGB image grabber. Flows size is $1500{\times}100{\times}180(mm)$, particle is Nylon12(1mm) and illuminator is Hollogen type lamp(100w). The stereo photogrammetry is adopted for the three dimensional geometrical mesurement of tracer particle. For the stereo-pair matching, the camera parameters should be decide in advance by a camera calibration. Camera parameter calculation equation is collinearity equation. In order to calculate the particle 3-D position based on the stereo photograrnrnetry, the eleven parameters of each camera should be obtained by the calibration of the camera. Epipolar line is used for stereo pair matching. The 3-D position of particle is calculated from the three camera parameters, centers of projection of the three cameras, and photographic coordinates of a particle, which is based on the collinear condition. To find velocity vector used 3-D position data of the first frame and the second frame. To extract error vector applied continuity equation. This study developed of various 3D-PIV animation technique.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.33 no.5
• /
• pp.741-751
• /
• 2009

In order to design and develop the various silhouette of pants pattern for standardized pants patterns, this study is to classify the pants style by the silhouette and to characterize each pants pattern which are classified. Recent 37 ready-made pants patterns of various style were collected in order to analyze their silhouette from April to July 2007. Measurement of each region of the pants pattern were compared and analysed. After analyse the standard deviation, coefficient of variance, minimum, maximum, range about the measurement of each region of the pants pattern, major pattern design factors were extracted. Five major factors are the angle of center front line and center back line, the crotch extension, the position of center back line against center front line, the curvature of center back line, and amount of waist dart. As a result, pants style were grouped as the culottes, formal, basic and tight style after considering the extracted design factors, and analysing correlation, degree of dispersion of the measurement by part. As the silhouette of pants classification from culotte to tight, the fits are closer to the figure, crotch depth increases, crotch extensions are shorter, and angle of the center back increases. The shape of the connected front and back center lines is U-shape for culotte and is closer to V-shape as the silhouette becomes tight.

• Journal of the Korean Society for Precision Engineering
• /
• v.13 no.6
• /
• pp.136-144
• /
• 1996

We developed a part of stroke sensing cylinder for position control of automatic excavator and its measurement system. In this paper, for development of stroke sensing cylinder, we consist of 2-axis control instrument system with Hall sensor. A performance of piston rod with magnetic scales is evaluated by the developed measurement system. Furthermore, the position control for good performance of instrument system is achieved by a sliding mode control which is a new method diminishing the chattering in that control by setting 2-dead band along the swtching line. The unknown parameters for sliding mode control are estimated by the signal compression method.

• Journal of the Korean Geophysical Society
• /
• v.7 no.4
• /
• pp.325-330
• /
• 2004

For the monitoring of structures, it is desirable for the measurement system to deliver equal precision in all components. When using GPS the accuracy, availability, reliability and integrity of the position solutions is very dependent on the number and geometric distribution of the available satellites. Therefore the positioning precision is not the same in all there component, and large variations (in positioning) precision can be expected during a 24-hour period. This situation becomes worse when the line-of-sight to GPS satellites becomes obstructed, such as in urban environments. Pseudolites can be sed to augment GPS and improve a geometrically weak satellite constellation. The use of pseudolites as supplement(s) of GPS for the movement measurement of bridges is demonstrated in this paper. It is shown that pseudollites can improve the vertical position components.

• 제어로봇시스템학회:학술대회논문집
• /
• 1988.10b
• /
• pp.822-825
• /
• 1988

In this paper, we present a system which enables a real-time measurement of the number and also the body length of the fry (baby fish) using a line image sensor. Here, we consider a situation that fry are transported from a pond to another, pond through a pipe. At one position of the pipe a transparent rectanglar channel is mounted. The images of the fry, which run through this rectanglar channel, are detected by a line image sensor. The image signals are digitized to binary ones and the contour of the fry are detected. After that, a real-time image analysis is executed with a digital signal processor. Labeling program analyses the connection of every pixel. The results are transfered to a personal computer and displayed on the online monitor graphically.

• Transactions of Materials Processing
• /
• v.16 no.4 s.94
• /
• pp.313-316
• /
• 2007

The purpose of this paper is the development of measurement algorithm for green-sheet based on the digital image processing technique. The Low Temperature Co-fired Ceramic(LTCC) technology can be employed to produce multilayer circuits with the help of single tapes, which are used to apply conductive, dielectric and/or resistive pastes on. These single green-sheets must be laminated together and fired at the same time. Main function of the green-sheet film measurement algorithm is to measure the position and size of the punching hole in each single layer. The line scan camera coupled with motorized X-Y stage is used. In order to measure the entire film area using several scanning steps, an overlapping method is used.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.11
• /
• pp.1031-1038
• /
• 2016

In the UAVs, the position error of the inertial navigation system is constantly increased when global positioning system goes wrong due to interference. It makes impossible to ensure mission and flight safety. If the data-link system provide the position of the UAV for inertial navigation system periodically, then the UAV may operate normally under malfunction of the global positioning system. In this paper, we introduce an algorithm for estimating the position of the UAV using the monopulse tracking and distance measurement of the line-of-sight data-link system. Also, we propose a method to improve the performance of position estimation. And we assured ourselves that this method can be applied in the UAVs.

• Nuclear Engineering and Technology
• /
• v.43 no.2
• /
• pp.133-140
• /
• 2011

In this paper, a deformation measurement technology for nuclear fuel rods is proposed. The deformation measurement system includes a high-definition CMOS image sensor, a lens, a semiconductor laser line beam marker, and optical and mechanical accessories. The basic idea of the proposed deformation measurement system is to illuminate the outer surface of a fuel rod with a collimated laser line beam at an angle of 45 degrees or higher. For this method, it is assumed that a nuclear fuel rod and the optical axis of the image sensor for observing the rod are vertically composed. The relative motion of the fuel rod in the horizontal direction causes the illuminated laser line beam to move vertically along the surface of the fuel rod. The resulting change of the laser line beam position on the surface of the fuel rod is imaged as a parabolic beam in the high-definition CMOS image sensor. An ellipse model is then extracted from the parabolic beam pattern. The center coordinates of the ellipse model are taken as the feature of the deformed fuel rod. The vertical offset of the feature point of the nuclear fuel rod is derived based on the displacement of the offset in the horizontal direction. Based on the experimental results for a nuclear fuel rod sample with a formation of surface crud, an inspection resolution of 50 ${\mu}m$ is achieved using the proposed method. In terms of the degree of precision, this inspection resolution is an improvement of more than 300% from a 150 ${\mu}m$ resolution, which is the conventional measurement criteria required for the deformation of neutron irradiated fuel rods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.689-692
• /
• 2015

That induced voltage by an electrified railway line is related with the position of telecommunication line between traction power feeding systems is practically varified by measurements in the real field. This experimented fact is conformed with the calculated simulation provided by the ITU-T Directives concerning the protection of telecommunication lines against harmful effects from electric power and electrified railway lines. Therefore it is needed to consider at what position a telecommunication line is parallelized with power feeding line of traction system when an induction phenomenon is evaluated or measurement is carried out besides the length of parallelization and the separate distance between power line and telecommunication line.

• Journal of ILASS-Korea
• /
• v.2 no.4
• /
• pp.29-35
• /
• 1997

Liquid film thickness is measured by $moir\acute{e}$ topography which monitored liquid surface. $Moir\acute{e}$ fringe measurement techniques share the inherent simplicity found in optical interferometric techniques have the advantage of use over a greater range of displacement. $Moir\acute{e}$ fringe are the geometric interference patterns observed when two dense line grating are superposed. Light transmitted through a fixed line grating is deviated by the liquid film surface, producing a distored image of the grating. The $moir\acute{e}$ fringe produced by projection of this optically distored grating onto a second stationary grating permit visualization of the liquid surface and measurement of the liquid film thickness. This study measured the small amplitude of liquid film thickness to the $moir\acute{e}$ fringe pattern produced when spherical metal was dropped glycerin put)1 And the measurement of liquid film thickness flowing down an inclined plate are required to calculate the liquid slope in a position.