• Journal of Korea Multimedia Society
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• v.2 no.1
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• pp.30-37
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• 1999

A wideband active noise cancelling system involves adaptive filters with hundreds of taps. The computational burden required with these long adaptive filters. This paper presents active noise cancelling system using M-channel QMF filter banks in which the adaptive weights are computed in subbands. The analysis and synthesis filter banks use cosine-modulated pseudo QMF filters. The reference signal for on-line identification of error path transfer characteristics is used to difference signal between the output of adaptive filters and the output of lowpass subband filters. The proposed adaptive subband filter bank suggests robust active noise cancelling system retaining the computational complexity and convergence speed advantaged of subband processing.

• The Transactions of the Korea Information Processing Society
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• v.2 no.3
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• pp.425-432
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• 1995

In this paper we propose a design and implementation technique of a universal automatic test pattern generator(UATPG) which is well suited for VLSI digital circuits. UATPG is designed to extend the capabilities of the existing APTG and to provide a convenient environment to computer-aided design(CAD) users. We employ heuristic techniques in line justification and fault propagation for functional gates during test pattern generation for a target fault. In addition, the flip-flops associated with design for testability (DFT) are exploited for pseudo PIs and pseudo POs to enhance the testabilities of VLSI circuits. As a result, UATPG shows a good enhancement in convenient usage and performance.

• Economic and Environmental Geology
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• v.17 no.1
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• pp.49-55
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• 1984

This paper describes three-dimensional (3-D) standard curves for conductive dipping buried bodies in induced polarization (IP) method. Dipole-dipole IP responses for the dipping bodies are calculated by the numerical modeling technique using an integral equation solution. Dip angles of the bodies are 0, 20, 45, 70 and 90 degrees, respectively. The horizontal (0-degree dip) and vertical (90-degree dip) bodies produce symmetrical patterns of IP responses. The dipping bodies of 20, 45 and 70 degrees, however, produce asymmertical patterns, with the highest IP contours dipping in the direction opposite to the bodies in pseudo-sections. The most remarkable asymmetrical pattern appears in the model of 20-degree dip. It is difficult to distinguish the body of 70-degree dip from that of 90-degree dip on the basis of dipole-dipole IP data. The IP pattern in pseudo-sections varies when the line moves away from the center of the body along strike, with the anomaly deeper and smaller in amplitude. IP maps seem to be more useful than IP pseudo-sections in predicting the location of target.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.81-116
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• 2001

The flora of vascular plants investigated in civilian control line area was 730 taxa consisting of 104 families, 331 genera, 631 species, 2 subspecies, 90 varieties, 7 formae. The forest was comparatively well conserved by Pteridophyta calculation(Pte-Q), 1.27. Among the investigated vascular plants, Korean endemic plants(Carex okamotoi, Salix koriyanagi, Clematis chisanensis, Aconitum pseudo-laeve var. erectum, Viola diamantiaca etc.) were 31 taxa; rare and endangered plants(Disporum ovale, Lilium distichum, Trillium kamschaticum, Gastrodia elata etc.) were 35 taxa; naturalized plants(Dactylis glomerata, Poa pratensis, Rumex acetosella, Gypsophila oldamiana, Lepidium apetalum etc.) were 26 taxa. The forest vegetation was classified into 1 order, 1 alliances, 6 communities; Rhododendro-Quercetalia mongolicae Kim 1990(신갈나무-철쭉군목), Lindero-Quercion mongolicae Kim 1990(신갈나무-생강나무군단), A. Carex humilis v. nana- Phinus densiflora Community 소나무-산거울군락, B. Acer pseudo-sieboldianum-Quercus mongolica Community 당단풍-신갈나무군락, C. Styrax obassia-Quercus mongolica Community 쪽동백-신갈나무군락, D. Acer palmatum-Quercus mongolica Community 단풍나무-신갈나무군락, E. Rheodendron mucronulatum-Quercus mongolica Community 진달래-신갈나무군락, F. Betula schmiditii-Quercus mongolica Community 박달나무-신갈나무군락

• Journal of Ocean Engineering and Technology
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• v.16 no.1
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• pp.64-70
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• 2002

This paper shows the results of the development of a small size of digital type continuous and intermittent welding auto-carriage based on microprocessor (Intel 80196KC) for welding process with long welding line. The developed welding auto-carriage loads welding torch and tracks welding line. It is an automaton largely used for welding process with a lot of long welding lines such as shipbuilding and structure. Most traditional auto-carriages have been developed based on analog circuit for open loop control. So this analog circuit welding auto-carriage cannon control welding speed. Specially welding auto-carriage for intermittent welding condition is so complicated and has the low precision of control performance in welding distance and non-welding distance. The auto-carriage developed in this paper has the following characteristics: It has not only functions of traditional carriage but also functions such as pseudo-welding process of big iron structures, intermittent welding in order to limit heat for welding thin plates, crater treatment of the final step of welding, acceleration at the initial step of welding and deceleration in the final step of welding. The main control board of auto-carriage, power supply system and DC motor drive wee developed and manufactured. The welding speed and the welding distance of the developed auto-carriage are controlled accurately by feedback control using photo-sensor. Hardware and software robust against the heat and noise produced on the welding process are developed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.3
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• pp.239-245
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• 2010

The present study is about an efficient extraction of tunnel cross sections from huge point cloud achieved by a terrestrial laser scanner. A method, using a hash-based data structure, is introduced, by which point clouds, potentially composing cross sections, are extracted along a tunnel center line. The center line is estimated by linking points which are drawn in the middle of pseudo cross sections based on the hash-based data structure. Point clouds of a same thickness are extracted at a same interval along the center line. In result, it took less than 3 seconds and 124 MB of memory to extract, out of the 7.5 million points, the point clouds of 1 m interval and 0.1 m thickness. A manual operation, however, was needed to fix the outliers on the center line and to select both start and end points on it.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.36.2-36.2
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• 2019

Fe II emission is a prominent and ubiquitous feature in the spectra of broad-line Active Galactic Nuclei (AGN) by producing a pseudo-continuum from UV to optical with complex and strong blends of the numerous emission lines themselves, other emission lines, and continuum. Since theoretical modeling of such intricate Fe II emission is very difficult and still far from able to reproduce observed data in detail, an empirical iron emission template, derived from observations of a narrow-line Seyfert 1 galaxy, is an essential and practical tool to obtain accurate measurements of all the emission lines and continuum in AGN spectra. However, the existing iron templates, based on the single prototypical strong Fe II emitter I Zw 1, are suffering from inadequate S/N and non-simultaneous, inconsistent data with limited wavelength coverage, which consequently limit the accuracy of all the spectral measurements. To overcome the limitations and construct an improved iron template with wide spectral coverage, high-quality UV and optical spectra for the new and better identified template galaxy, Mrk 493, were successfully obtained from our HST STIS program (GO-14744). We will show the preliminary results for multicomponent spectral decomposition of the data and template construction with application tests to various AGN spectra and comparison with previous templates.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.170-177
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• 1993

In robotic arc welding, the roll (rotation) of the torch about its direction vector does not have any effect on the welding operation. Thus we could use this redundant degree of greedom for the motion control of the robot manipulator. This paper presents an algorithm for the pseudo- inverse kinematic motion control of the 6-axis robot, which utilizes the above mentioned redunancy. The prototype welding operation and the tool path are also graphically simulated. Since the proposed algorithm requires only the position and normal vector of the weldine as an input data, it is useful for the CAD-based off-line programming of the arc welding robot. In addition, it also has the advantages of the redundant manipulator motion control, like singularity avoidance and collision free motion planning, when compared with the other motion control method based on the direct inverse kinematics.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.783-788
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• 2003

In this paper, we present a new approach to detect and recognize human face in the image from vision camera equipped on the mobile robot platform. Due to the mobility of camera platform, obtained facial image is small and pose-various. For this condition, new algorithm should cope with these constraints and can detect and recognize face in nearly real time. In detection step, ‘coarse to fine’ detection strategy is used. Firstly, region boundary including face is roughly located by dual ellipse templates of facial color and on this region, the locations of three main facial features- two eyes and mouth-are estimated. For this, simplified facial feature maps using characteristic chrominance are made out and candidate pixels are segmented as eye or mouth pixels group. These candidate facial features are verified whether the length and orientation of feature pairs are suitable for face geometry. In recognition step, pseudo-convex hull area of gray face image is defined which area includes feature triangle connecting two eyes and mouth. And random lattice line set are composed and laid on this convex hull area, and then 2D appearance of this area is represented. From these procedures, facial information of detected face is obtained and face DB images are similarly processed for each person class. Based on facial information of these areas, distance measure of match of lattice lines is calculated and face image is recognized using this measure as a classifier. This proposed detection and recognition algorithms overcome the constraints of previous approach [15], make real-time face detection and recognition possible, and guarantee the correct recognition irregardless of some pose variation of face. The usefulness at mobile robot application is demonstrated.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.6
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• pp.47-56
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• 2015

In the multi-sensor system, sensor registration errors such as a sensor bias must be corrected so that the individual sensor data are expressed in a common reference frame. If registration process is not properly executed, large tracking errors or formation of multiple track on the same target can be occured. Especially for launch vehicle tracking system, each multiple observation lies on the same reference frame and then fused trajectory can be the best track for slaving data. Hence, this paper describes an on-line bias estimation/correction and asynchronous sensor fusion for launch vehicle tracking. The bias estimation architecture is designed based on pseudo bias measurement which derived from error observation between GPS and radar measurements. Then, asynchronous sensor fusion is adapted to enhance tracking performance.