• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.9
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• pp.64-75
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• 1993

This paper proposes a recovering technique of the elevation map by stereo modeling of the aerial image sequence which is transformed based on the aircraft situation. The area-based stereo matching method is simulated and the various parameters are experimentally chosen. In a depth extraction step, the depth is determined by solving the vector equation. The equation is suitable for stereo modeling of aerial images which do not satisfy the epipolar constraint. Also, the performance of the conventional feature-based matching scheme is compared. Finally, techniques analyzing the accuracy of the recovered elevation map (REM) are described. The analysis includes the error estimation for both height and contour lines, where the accuracy is based on the measurements of deviations from the estimates obtained manually. The experimental results show the efficiency of the proposed technique.

• Journal of the Korean Society of Costume
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• v.34
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• pp.19-36
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• 1997

through Sid View Silhouette The purpose of this study was to pro-vide basic information for elderly women's clothing construction and to develop dress forms that can reflect the charac-teristics of their bodies. The subjects were 251 elderly women aged from 60 to 81. Data were collected from 34 photographic measurements of each subject and analyzed by factor analysis cluster analysis analysis of variance. The results were as follows: 1. A decrease in height the bustline drops as age increase. From a lateral view point most of the subjects have straight posture with protruding ab-domens but the somatotype gradually bends bends forward with age. 2) Five factors were extracted from photometric measurement which explain 81.0% of variance. 3 Through cluster analysis using 5 fac-tor scores four types were categorized. Type I was turning over somatotype Type II was swayback somatotype Type III was straight somatotype Type IV was bending somatotype according to its po-sition to the relative plumb liner and their side view contour.

• Journal of the Semiconductor & Display Technology
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• v.5 no.1 s.14
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• pp.27-31
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• 2006

Non-contact transportation system using air cushion for the manufacturing of large-sized LCD panels was considered. Flow characteristics between air pad and glass plate was analyzed using computational fluid dynamics method to obtain optimized air pad configurations. Effects of the design variables such as hole arrays from which gas is injected, gas-feeding method into the gas supplying channels, and horizontal and vertical pitches of clusters of holes were studied. Optimized air pad unit gave evenly distributed pressure contour on the glass surface and well-suspended levitation height in the experiment.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.31
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• pp.155-161
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• 1994

This study presents a systematic and mere economical method to acquire 3-D anthropometric data by the use of Moire' interferometry, image processing and computer vision techniques. An experiment was performed to measure sixty-one anthropometric variables, such as height weight neck-base circumference, contained areas of various contours etc.., of thirty-six male subjects with wide range of ages (14 years to 43 years' old). Cluster analysis was performed with contour information, and somatotyping was performed to obtain four distinct types of body shape. The results were then compared with classifications obtained from traditional somatotyping methods which showed 71.88% consistency. This study developed a simple and inexpensive method for 3-D anthropometric data acquisition and suggests the quantification and interpretation scheme that will enable us to utilize the data for industrial applications.

• The Journal of the Korean dental association
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• v.54 no.5
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• pp.328-341
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• 2016

An overall reduction in the horizontal and vertical dimensions occurs following tooth extraction and the resorption of the buccal part of the ridge is more pronounced than the lingual part. Thus, the resulting morphology of the healed alveolar ridge is often presenting with a discrepancy in bone height between the buccal and lingual aspects of the ridge. The implant with a sloped marginal configuration that is designed to match the sloped contour of the alveolar ridge provides the opportunity to maintain the buccal-lingual bone discrepancy and soft tissue around the implant. This paper introduces the OsseoSpeed TX Profile implants with sloped marginal configuration and explains the characteristics and clinical meanings of those implants.

• The Transactions of the Korea Information Processing Society
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• v.1 no.3
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• pp.409-417
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• 1994

In extracting contours from elevation matrix, the most important problem is to solve the degenerate case where four cross point arise in a grid. This paper describes a technique which performs the checking of degenerate case and determination of next point simultaneously. It requires minimum number of array indexing. Also this paper proposes a technique which reduces the number of array indexing by using LOWER/HIGHER information of a cross point designated according to height difference of grid vertices. In addition, we describe a data structure which is proper for representing cross points and tracing them.

• 한국연소학회:학술대회논문집
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• 2002.06a
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• pp.61-67
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• 2002

Characteristics of lifted flames in axisymmetric laminar coflow jets have been investigated experimentally. Approximate equations for velocity and concentration with virtual origins have been proposed to analyze the behavior of flames in coflow jets. Measuring Rayleigh intensity to investigate the concentration field. proposed approximate equations were confirmed. By using the results of OH PLIF, direct photography and Rayleigh scattering measurement, it is shown that the locations of maximum intensity in direct photography coincide with the tribrachial points in axisymmetric jets and the tribrachial points travel on the stoichiometric contour. For coflow jets, the experimental results of liftoff height have been successfully correlated with nozzle exit velocity using predicted behavior from proposed approximated equations. These results substantiate the stabilization mechanism in coflow jet is based on the balance between flame propagation speed and axial flow velocity, same as for the free jets.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.129-137
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• 1999

A parametric curve interpolator has been proposed for machining curves instead of a linear interpolator in which curves are approximated by a set of line segment. The parametric curve interpolator is superior to linear interpolator in machining time and contour error and generate exact position commands directly from curve equations. In this paper, a new toolpath generation method is proposed based on the parametric curve interpolator. This method retains all the benefits of parametric curve interpolator and can bound the scallop height within a specified value. By interpolating curves and surfaces directly from the mathematical equations, the amount of data from CAD/CAM system to CNC controller can be significantly reduced. The proposed method was implemented on a CNC controller and was confirmed to give a better result than the other existing method.

• Journal of Welding and Joining
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• v.15 no.6
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• pp.116-123
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• 1997

In GMA welding processes, bead contour and penetration patterns are criterion to estimate weld quality. Bead geometry is commonly defined with width, height and depth. When weaving is taken into account, selection of welding conditions is known to be difficult. Thus, empirical or trial-and-error method are usually introduced. This study examined the correlation of welding process variables including weaving parameters with bead geometry using srtificial neural networks(ANN). The main task of the Ann estimator is to realize the mapping characteristics from the sampled welding process variables to the actual bead geometry through training. After the neural network model is constructed, welding process variables for desired bead geometry is selected by inverse model. Experimental varification of the inverse model is conducted through actual welding.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.1
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• pp.34-46
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• 2020

Computational assessment of gas-dynamic characteristics is explored for a three-dimensional counter-flow thrust vector control system in a rectangular supersonic nozzle. This convergent-divergent nozzle is designed by Method of Characteristics and its design Mach number is specially set as 2.5. Performance variations of the counter-flow vector system are illustrated by varying the gap height of the secondary flow duct. Key parameters are quantitatively analyzed, such as static pressure distribution along the centerline of the upper suction collar, deflection angle, secondary mass flow ratio, and resultant thrust coefficient. Additionally, the streamline on the symmetry plane, three-dimensional iso-Mach number surface contour, and three-dimensional turbulent kinetic energy contour are presented to reveal overall flow-field characteristics in detail.