• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.3
• /
• pp.139-146
• /
• 2004

A 2D/3D complex optical system and its vision inspection algerian is proposed and implemented as a single probe system for high speed, precise vision inspection of the solder pastes. One pass un length labeling algorithm is proposed instead of the conventional two pass labeling algorithm for fast extraction of the 2D shape of the solder paste image from the recent line-scan camera as well as the conventional area-scan camera, and the optical probe path generation is also proposed for the efficient 2D/3D inspection. The Moire interferometry-based phase shift algerian and its optical system implementation is introduced, instead of the conventional laser slit-beam method, for the high precision 3D vision inspection. All of the time-critical algorithms are MMX SIMD parallel-coded for further speedup. The proposed system is implemented for simultaneous 2D/3D inspection of 10mm${\times}$10mm FOV with resolutions of 10 ${\mu}{\textrm}{m}$ for both x, y axis and 1 ${\mu}{\textrm}{m}$ for z axis. Experiments conducted on several nBs show that the 2D/3D inspection of an FOV, excluding an image capturing, results in high speed of about 0.011sec/0.01sec, respectively, after image capturing, with $\pm$1${\mu}{\textrm}{m}$ height accuracy.

• Journal of Bio-Environment Control
• /
• v.24 no.3
• /
• pp.210-216
• /
• 2015

Purpose of this study was a development of an image processing algorithm to recognize paprika and acquire it's 3D coordinates from stereo images to precisely control an end-effector of a paprika auto harvester. First, H and S threshold was set using HSI histogram analyze for extracting ROI(region of interest) from raw paprika cultivation images. Next, fundamental matrix of a stereo camera system was calculated to process matching between extracted ROI of corresponding images. Epipolar lines were acquired using F matrix, and $11{\times}11$ mask was used to compare pixels on the line. Distance between extracted corresponding points were calibrated using 3D coordinates of a calibration board. Non linear regression analyze was used to prove relation between each pixel disparity of corresponding points and depth(Z). Finally, the program could calculate horizontal(X), vertical(Y) directional coordinates using stereo camera's geometry. Horizontal directional coordinate's average error was 5.3mm, vertical was 18.8mm, depth was 5.4mm. Most of the error was occurred at 400~450mm of depth and distorted regions of image.

• 한국HCI학회:학술대회논문집
• /
• 2008.02b
• /
• pp.470-474
• /
• 2008

The image as a media has changed consistently since it was first introduced. According to these changes, the image has been reproduced in different fields and contexts. Thus, the paradigm on the production and the consumption of the image has been changed and recycled rapidly. The relation between the production and the consumption of the image also has changed accordingly, allowing quite ambiguous distinction between the producer and the consumer. The transformation through the transfer of the image among different fields opens up a new potential that these reproduced images could be used as an aesthetically expressive tool, rather than merely leaving images to remain royal to its original function as a sign. The thesis is to explore the potential that the topographical lines have beyond its function as a sign age. During the reproduction of the image, the process actively invites the spectator or the consumer to participate in the formation of the image, which promotes a new relation between the producer and the consumer. Instead, the process encourages the consumers to be active producers as well. As a result, the topographical lines do not merely remain as a sign that demarcates the height of the topography, and new images are constantly reproduced from the active participants. This project questions the fixed idea on the sign as a communicative tool, and suggests a new potential for the sign, especially, the topographical lines.

• Journal of the Korea Convergence Society
• /
• v.9 no.9
• /
• pp.183-189
• /
• 2018

This study deals with the design and development of imaging optics having 24mm focal length for MWIR ($3{\sim}5{\mu}m$) with two symmetrical lenses facing each other. We used CodeV in our optical design, and we performed the optimization process to have the resolution and angle of view satisfying the user's requirements. The materials of lenses were limited to two types, including KCIR035 with a refractive index of 1.7589, developed in Korea. The optical system designed in this way consists of two aspherical lenses made of KCIR035 material having the same shape and one spherical lens made of Si. Here, the arrangement of the two aspherical lenses is characterized by having a symmetrical structure facing each other. And this optical system has a resolution of MTF value of 0.35 or more at a line width of 20 lp / mm. Therefore, it is considered that this optical system has the capability to be applied to a thermal imaging camera using a $206{\times}156$ array MWIR detection device having a pixel size of $25{\mu}m$.

• Korean Journal of Applied Biomechanics
• /
• v.26 no.3
• /
• pp.315-321
• /
• 2016

Objective: The aim of this study was to analyze effects of the toe-spring angle of bobsleigh shoes on start speed lap time to develop Korean-specific bobsled shoes suitable for winter environments and for domestic players on the basis of sports science and optimized biomechanical performance. Method: Seven Korean bobsleigh athletes participated in this study, with three pairs of sprint spikes from three companies (Type A, Type B, Type C). To analyze sprint lap time and forefoot bending angle for each shoe, participants were instructed to drag a sled 15 meters from the start line at a maximum sprint. forefoot bending angle was collected by a high speed camera, and lap time speed was measured. Results: Lap time for type B shoes was $3.52{\pm}0.17sec$, type A was $3.55{\pm}0.19sec$, and type C was $3.56{\pm}0.18sec$. Forefoot bending angles were: angle 1, $6.88{\pm}5.55^{\circ}$; angle 2, $9.23{\pm}6.38^{\circ}$; angle 3, $15.56{\pm}5.39^{\circ}$; angle 4, $9.54{\pm}3.85^{\circ}$; angle 5, $9.22{\pm}5.08^{\circ}$; angle 6, $7.66{\pm}6.44^{\circ}$; and angle 7, $4.30{\pm}6.24^{\circ}$ (p<.001). Forefoot bending in angle 3 was as follows: type A, $16.47{\pm}6.01^{\circ}$; type B, $14.30{\pm}4.96^{\circ}$; and type C, $15.90{\pm}5.17^{\circ}$. Conclusion: Hard outsoles and midsoles are better than soft type for reduced start lap time when developing a prototype Korean bobsled shoe.

• Korean Journal of Remote Sensing
• /
• v.31 no.2
• /
• pp.85-99
• /
• 2015

TDI CCD sensors are being used for most of the electro-optical camera mounted on the low earth orbit satellite to meet high performance requirements such as SNR and MTF. However, the CMOS sensors which have a lot of implementation advantages over the CCD, are being upgraded to have the TDI function. A few methods for improving the issue of motion blur which is apparent in the CMOS sensor than the CCD sensor, are being introduced. Each pixel can be divided into a few sub-pixels to be read more than once as is the same case with three or four phased CCDs. The fill factor can be reduced intentionally or even a kind of mask can also be implemented at the edge of pixels to reduce the blur. The motion blur can also be reduced in the TDI CMOS sensor by reducing the integration time from the full line scan time. Because the integration time can be controlled easily by the versatile control electronics, one of two performance parameters, MTF and SNR, can be concentrated dynamically depending on the aim of target imaging. MATLAB simulation has been performed and the results are presented in this paper. The goal of the simulation is to compare dynamic MTFs affected by the different methods for reducing the motion blur in the TDI CMOS sensor.

• Journal of the Korean Wood Science and Technology
• /
• v.37 no.1
• /
• pp.37-47
• /
• 2009

For the inspection of wood, machine vision is the most common automated inspection method used at present. It is required to sort wood products by grade and to locate surface defects prior to cut-up. Many different sensing methods have been applied to inspection of wood including optical, ultrasonic, X-ray sensing in the wood industry. Nowadays the scanning system mainly employs CCD line-scan camera to meet the needs of accurate detection of lumber defects and real-time image processing. But this system needs exact feeding system and low deviation of lumber thickness. In this study low cost CCD area sensor was used for the development of image processing system for lumber being fed. When domestic red pine being fed on the conveyer belt, lumber images of irregular term of captured area were acquired because belt conveyor slipped between belt and roller. To overcome incorrect image merging by the unstable feeding speed of belt conveyor, it was applied template matching algorithm which was a measure of the similarity between the pattern of current image and the next one. Feeding the lumber over 13.8 m/min, general area sensor generates unreadable image pattern by the motion blur. The red channel of RGB filter showed a good performance for removing background of the green conveyor belt from merged image. Threshold value reduction method that was a image-based thresholding algorithm performed well for knot detection.

• Journal of KIISE:Computing Practices and Letters
• /
• v.7 no.2
• /
• pp.132-140
• /
• 2001

This paper proposes an efficient walktlu-ough animation from two images of the same scene. To make animation easily and fast, Tour Into the Picture(TIP) enables walkthrough animation from single image but lacks the reality of its foreground object when the viewpoint moves from side to side, and view morphing uses only 2D transition between two images but restricts its camera path on the line between two views. By combining advantages of these two image-based techniques, this paper suggests a new virtual navigation technique which enable natural scene transformation when the viewpoint changes in the side-to-side direction as well as in the depth direction. In our method, view morphing is employed only in foreground objects , and background scene which is perceived carelessly is mapped into cube-like 3D model as in TIP, so as to save laborious 3D reconstruction costs and improve visual realism simultaneously. To do this, we newly define a camera transformation between two images from the relationship of the spidery mesh transformation and its corresponding 3D view change. The result animation shows that our method creates a realistic 3D virtual navigation using a simple interface.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.4 no.2
• /
• pp.77-87
• /
• 1986

As for the deformation measurement of structure, there are many controversial points in using the methods by the strain guage, inclinometer, bial guage, and geodetic method because of the difficulty of instrument setting and the problem in the degree of accuracy of the results as well as in the economical aspect. Therefore, to verify the superiority of the Close- Range Photogrammetry method for the structural deformation measurement, the result of load deformation on the model structure, which was made using the Close-Range Photogrammetry method was compard with the results which was made using the methods of dial guage, precision level, and triangulation. In addition to that, to consider the general problem which would happen when C. R. P method was applied to the practical structure. The elements of C. R. P method like camera rotation angle ($\psi$,$\omega$), exposure elevation (Z$_{L}$), and angle of inclined base line ($\theta$) were experimented, and their specificities were reconsidered. As a result, the application of C. R. P method to the general structure is expected to be increased not only in the aspect of accuracy but in the economical aspect.t.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.796-798
• /
• 2002

In these days, the interruption capability of some circuit breakers, which are installed in the transmission systems, is getting lower than the magnitude of the fault current because of continuous increase of power demand and relatively short power line which was installed in forms of mesh network As a result of these situations, fault current limiters (FCLs) are strongly necessary. There are various types which is investigated around the world, and new power apparatuses that have been newly considered and developed by many manufactures. In this paper, we considered resistive superconducting fault current limiters with YBCO thin films. The resistive limiters utilize a transition of YBCO films from superconducting to normal state caused by exceeding the critical current. By means of newly occurred impedance, the fault current will be limited effectively. Generally, a few current path patterns are available for YBCO films to enhance the current limiting performance of YBCO films. In this paper. the meander-type and the bi-spiral-type were used for current paths of YBCO flims. When YBCO films are quenched into the normal state, bubbles could be observed on the surface of YBCO films. Using our high-speed camera, the number of bubbles and the size of bubbles could be visualized and the relation between bubbles and current density was analyzed. By means of moving pictures of bubbles, we observed how the quench extended or how the heat was conducted in films.