• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.703-705
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• 1999

The Power supplies used commonly in the Nuclear, Thermal and Hydraulic Power Plant are required to test the function and reliabilities. For the better contribution of reliable operation and speedy maintenance of Power Plant, it is necessary to gather and analyze the datum, to print out the result of testing using PC and proper controllers. Various kinds of power supply shall be tested and examined automatically. By storing the test results in the Database it is possible to find out the changing of characteristics of power supplies. So it is very useful to prevent any problems that may occur in the power supplies.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.215-218
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• 1995

This paper presents an experimental study on the strength and deformation of concrete-filled circular steel short columns. Six specimens of concrete-filled circular short columns were tested under concentric compressive load. For comparsion, three specimens of circular steel short columns were also loaded to failure. The ultimate strength, ductility, and confinement mechanism of columns were compared. In the comparison, the effect of witch-thickness ratio and concrete compressive strength on the behavior of colimns were examed. As a result, the axial load verse axial average strain relationship of concrete-filled circular steel columns was very stable, because of interactions between the concrete and steel, the strength are 13% and 30% larger than the strength extimated by simply superimposed method of the concrete and steel. The ratio of the circumferential to longitudinal strain increment, both measured on the steel suface, was 0.28 up to the longitudinal strain of 0.1%, increases from 0.3 to 0.8 between the strain of 0.1% to 0.3%, and 0.8 beyond the strain of 0.3%

• Journal of IKEEE
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• v.12 no.1
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• pp.51-58
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• 2008

This paper presents a new method for building detection and reconstruction from aerial images. In our approach, we extract the useful building location information from the generated disparity map to obtain the segmentation of interested objects and thus reduce significantly unnecessary line segment extracted in low level feature extraction step. Hypothesis selection is carried out by using undirected graph in which close cycles represent complete rooftops hypotheses, and hypothesis are finally tested to contruct building model. We test the proposed method with synthetic images generated from Avenches dataset of Ascona aerial images. The experiment result shows that the extracted 3D line segments of the buildings can be efficiently used for the task of building detection and reconstruction from aerial images.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.614-619
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• 1988

In this paper, an arbitrary mission of a spacecraft from launch to orbit injection is investigated for some launch trajectories. Launch sites are selected arbitrarily from various locations in Korea. For this study, a general purpose simulation program is developed. In this program, the Earth is assumed to be a rotating ellipsold. The launch vehicle is treated as a 3-D, 6-DOF rigid body. The developed program has been evaluated by calibrating it to the 3-stage N-1 rocket developed in Japan and launched at Tanegasima. The simulated trajectory from the first-stage ignition to burnout of third-stage main engine is compared with the previously tested N-1 rocket trajectory in Japan. The result shows that the program works properly. Using the proven program, we have investigated possible launch locations in Korea, namely Marado, Sungsan and Kuryongpo. The problem of polar orbit injection is also examined.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.308-312
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• 1989

We developed a model of NC controller with IBM-PC as a host cpu and integlligent NC servo controller for 2 axes that can be expaned to 4 axes. Basic conceptions, including hardware structure design, servo controller design, communication protocol, and interpolation hardware design was already publicated on '87 KIEE conference. Following this, we focussed on the emulation of tyhe controller with X-Y table as complete NC machine experimenting some drawings made by NC code program that can be edited and executed in automatic on single step mode. In addition we designed the M.S.T functions with PLC and tested for M-function timing. Finally, we designed NC interface to fit with M-function output and we contructed total system of NC controller with IBM PC host with the result of successful development of new NC model.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.10
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• pp.8-18
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• 1997

In FPGAs, we may use the property of the routing architecture for their routing compared to the routing in the conventional layout style. Especially, the Xilinx XC4000 series FPGAs have very special routing architecture in which the routing problem is equivalent to the two dimensional track assignment problem. In this paper, we propose a new FPgA detailed routing method by developing a two dimensional trackassigment heuristic algorithm. The proposed routing mehtod accept a global routing result as an input and obtain a detailed routing such that the number of necessary wire segments in each connection block is minimized. For all benchmark circuits tested, our routing methd complete routing results. The number of used tracks are also similar to the results by thedirect routing methods.

• Journal of the Korean Home Economics Association
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• v.32 no.1
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• pp.93-102
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• 1994

The purpose of this study was to investigate the suitability of several knit fabrics for the hadicapped children's slacks. After the observation and wearing test abrasion resistance pilling liquid water transport properties and heat transport properties of the fabrics were tested. As specimens cotton/polypropylene interlock knits and sweat absorbent polyester knit fabric were selected and compared to the cotton denim and wool fabrics. As a result of observation test importance of extensibility durability and comfort related properties were recognized. Through the wearing test depending on the handicap type and orthoses different location and grade of pilling were observed. Knit fabrics used in this experiment were as durable as woven fabrics and showed excellent heat and liquid water transport properties. It was concluded therefore that cotton/polypropylene and sweat absorbent polyester knit fabrics are suitable materials for handicapped children's slacks.

• 한국전산유체공학회:학술대회논문집
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• 1998.11a
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• pp.197-203
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• 1998

The discrete element method is a numerical model capable of describing the mechanical behaviour of assemblies of discs and spheres. The method is based on the use of an explicit numerical scheme in which the interaction of the particles is monitored contact by contact and the motion of the particles modelled particle by particle. In this paper, A two-dimensional model for computing contacts and motions of granular particles of unform, inelasticity is presented. And, code is developed. The primary aim of this paper is to approv computational result of continuum alaysis which is on processing. The end of this paper, that code is tested with several examples.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.276-287
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• 1990

In this paper research result of transient thermal stress analysis of power plant turbine rotors for life prediction under severs operating conditions is presented. Galerkin's recurrence scheme is used for numerical solution of discretized FEM equation of transient heat conduction equation. Boundary conditions for the equation and operating conditions are intensively investigated for accurate life prediction of turbine rotors in operation. A computer program for on-site application is developed and tested. Distribution of thermal stress in turbine rotors during various operating condition is analyzed with the program and it is found that the peak thermal stress appears during cold stage conditions at the first stage of high pressure rotors.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.467-474
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• 1993

Viscous flow and heat transfer phenomena in an axisymmetric cylinder which models a diesel engine have been numerically studied. In order to search for a way to minimize numerical diffusion, the effectiveness and the appropriateness of two selected numerical schemes for convective terms in the governing equations have been tested. They are Linear Upwind Difference Scheme and Hybrid Scheme. Using a standard k-.epsilon. turbulence model, the calculation has been carried out basically up to 180.deg. of crank angle. As a result, it was shown from comparison with previous experimental data that Linear Upwind Difference Scheme is less influenced than Hybrid Scheme by the numerical diffusion and it was suggested that these effects of numerical diffusion can be more significant than those due to turbulence modeling.