• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.418-421
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• 2008

This paper presents the program to analyze an antenna for using the Moment Method. The program contains three different functional steps. In the first stage, the pre-processor is based on the Delaunay Triangulation Algorithm. The next stage, the main-processor, can be considered the core process of the program, which solutions are obtaining the linear matrix for using the Moment Method. The final stages, the name of the post-processor, analyze radiation patterns, which results are same with the S-parameters. The results demonstrate satisfactory agreement with the results for using other numerical packages and measurement data. We can confirm that the results of this program compare with the results of common program to analyze for an antenna.

• Economic and Environmental Geology
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• v.23 no.3
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• pp.359-366
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• 1990

Field sampling requires statistical description to draw inferences from data. Field data, or linear structures, are commonly analyzed by the graphical presentations, such as streonets and rose diagrams. For this purpose the DROPOL program is developed to analyze the data more efficiently with personal computer. DROPOL program written in FORTRAN 77 plots the structural data in points, poles or great circle on equalarea (Schmidt net) or equal-angle (Wulff net) projection surface. It is also capable to project the data from upper or lower hemisphere of stereonet and to draw pole contour diagrams from the plotted data. The rose diagram, representing the frequency of the strike and dip angle, can also be drawn in general or smooth type using $5^{\circ}$ or $10^{\circ}$ degrees interval.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.2
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• pp.389-396
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• 1988

Microprocessor-based software DDA interpolator is developed and applied to two axis contouring control of X-Y table. Developed assembly program is composed of feedrate, linear and circular DDA interpolation routines. Reference-pulse type of open-loop stepping motor control system in which the micro-computer produces a sequence of reference pulses for each axis of motion is adopted. To test performance of the developed program, X-Y table drive system based on stepping motor and shaft encoder is designed. Conturing error of the system in linear and circular path is within .+-. 0.2mm under start stop pulse rate of stepping motor.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.304-307
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• 2008

A spreadsheet-based linear program (LP) software, so called, the LP-Tableau is developed to aid users to learn the simplex algorithm systematically and to understand the various conditions that make the problem unusual and, in some instances, impossible to solve. The LP-Tableau has several good features over other spreadsheet-based LP software programs available. First, the data input in the LP-Tableau is very convenient especially when small-sized problems are analyzed. Further, the LP-Tableau allows for two solution methods (i.e., Big-M and Two-Phase) and displays the whole iterations in tableau format. Thus users can easily understand the principle of the algorithm step by step. Finally, the LP-Tableau visually displays various conditions of the optimal solutions that might occur in solving the LP problems.

• KIEE International Transactions on Power Engineering
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• v.5A no.4
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• pp.371-377
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• 2005

Congestion problems of transmission lines are very important research issues in power system operations. Load curtailment is one of the ways to solve congestion problems by a major contingency. A systematic and effective mechanism for load shedding has been developed by investigating congestion distribution factors and the direct load control program. In this paper, a load shedding algorithm using linear programming for congestion problems by a major contingency is presented. In order to show the effectiveness of the proposed algorithm, it has been tested on the 6-bus sample system and the power system of Korea, and their results are presented.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.49.2-49.2
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• 2017

With support from the K-GMT science program (PID: GN-2016B-Q-14), we conducted observations of active asteroid 354P/LINEAR (2010 A2) when it made its closest approach to Earth (i.e., the geocentric distance of 1.06 au on 2017 January 27-28). Taking advantage of the best observing geometry since the discovery, we obtained the first evidence for the rotational status of the largest fragment (~120 m in diameter), which was slowly rotating, that is, the rotational period of 11.36 hours. In addition, we succeed in direct imaging of 10 sub-fragments (~20 m in diameter or larger). Based on these new observational results, we conjecture that this active asteroid was created as a result of catastrophic collision among unknown asteroids. The details of this work are given in Astrophysical Journal Letters, 842, L23.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.12
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• pp.2492-2502
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• 2002

A rubber-like material model is generally characterized by hyperelasticity and formulated by a total stress-total strain relationship because the material shows nonlinear elastic behaviour under large deformation. In this study, a pressure potential obtained by a separately interpolated pressure is introduced to the non-linear finite element formulation incorporating with incompressible or almost incompressible condition of the material. The present formulation is somewhat different from the general formulation using the pressure computed in the displacement field. A non-linear finite element analysis program is developed for the plane strain and the axisymmetric contact problems of a rubber-like material. Various examples with rubber material are analyzed for its verification. The results about deformed shapes and stress distributions thought to be meaningful in comparison with a commercial program, MARC.

• IE interfaces
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• v.10 no.3
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• pp.179-187
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• 1997

The efficiency of material flow systems in terms of optimal network flow and minimum cost flow has always been an important design and operational goal in material handling and distribution system. In this research, an attempt was made to develop a new algorithm and the model to solve a stochastic material flow network with bidirectional and uncertain flows. A stochastic material flow network with bidirectional flows can be considered from a finite set with unknown demand probabilities of each node. This problem can be formulated as a special case of a two-stage linear programming problem which can be converted into an equivalent linear program. To find the optimal solution of proposed stochastic material flow network, some terminologies and algorithms together with theories are developed based on the partitioning and subgradient techniques. A computer program applying the proposed method was developed and was applied to various problems.

• Bulletin of the Korean Chemical Society
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• v.15 no.1
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• pp.57-63
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• 1994

Digital simulation program for one-dimensional geometric systems of electrochemical phenomena was developed. The accuracy of the digital simulation is discussed by comparing with the known solutions. Applying this program to the linear sweep voltammetry at a planar electrode for the electrode reaction, 0 + ne${\to}$R, the accurate current functions for the reversible and totally irreversible charge transfer systems were obtained. Comparing these current functions with the simulated voltammograms for various other values of ${\alpha}$ (0.1 to 1.0) and ${\Lambda}\;(10^{-5}\;to\;10^5)$, the revised zones that are different from those proposed by Matsuda and Ayabe for the reversible and totally irreversible systems are proposed. For ${\alpha}{\ge}$0.1 the reversible zone is in ${\Lambda}{\ge}10^{1.7}$ and the totally irreversible zone is in ${\Lambda}{\le}10^{-1.7}$, where ${\Lambda}=k^{\circ}/ [D_o^{1-{\alpha}}D_R^{\alpha}(nF/RT)v]^{1/2}$.

• Journal of the Semiconductor & Display Technology
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• v.19 no.4
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• pp.18-21
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• 2020

Undetected wafer slip during the lift pin-down motion in semiconductor equipment may affect the center to edge variation, wafer warpage, and pattern misalignment in plasma equipment. Direct measuring of the amount of wafer slip inside the plasma process chamber is not feasible because of the hardware space limitation inside the plasma chamber. In this paper, we demonstrated a practice for the wafer lift pin-up and down motions with respect to the gear ratio, operating voltage, and pulse width modulation to maintain accurate wafer position using remote control linear servo motor with an experimentally designed chamber mockup. We noticed that the pin moving velocity and gear ratio are the most influencing parameters to be control, and the step-wised position control algorithm showed the most suitable for the reduction of wafer slip.