• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.591-596
• /
• 2022

Since 4-bar linkage widely used in various industrial fields has a fixed link length, it is inconvenient to add an independent link structure or control device to change the movement of output link. Therefore, this paper proposes a new concept of variable 4-bar linkage mechanism to selectively adjust the movement of the output link to fit desired situations, and applied to the commercial table fans, which is a representative product using a 4-bar linkage system. The optimal rotation angle steps for efficiency are determined experimentally and the appropriate lengths of linkage to fit each step are calculated analytically. Changes in the linkage length are implemented by the rotational motion using a grooved cylindrical cam and the feasibility of the proposed variable linkage mechanism is verified through fabrication and measurement. The presented variable link mechanism is expected to improve the efficiency of industrial robots and fuel valve systems.

• Proceedings of the KIEE Conference
• /
• 1990.11a
• /
• pp.227-230
• /
• 1990

In this paper we present a variable structure systeme-model following adaptive control (VSS-MFAC) method for an uncertain turbo-generator system which is apt to suffer from the unmodeled parameter uncertainties and the external disturbances. The simulation results for the power system stabilizer(PSS) exhibit robust adaptive model-following properties well in the PSS designed by the proposed VSS-MFAC methodology when a step change in the mechanical torque and a parameter variation is applied.

• 한국전산유체공학회:학술대회논문집
• /
• 2000.10a
• /
• pp.78-85
• /
• 2000

The transient laminar reacting flows around fuel droplet have been numerically analyzed. The physical models used in this study can account for the variable thermophysical properties and the chemistry is represent by the one-step global reaction model. The present study is focused on the vaporization and ignition characteristics, flame structure including wake flame, transition flame and envelope flame, and interaction between droplets. special emphasis is given to the triple flame structure and flame stabilization.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.1217-1220
• /
• 1996

For the purpose of the good tracking to variable load demands of the thermal power plant, a decentralized multilevel control(DMC) scheme is presented. It is applied to the drum type boiler-turbine system which is simplified from Boryung T/P #1,2 model[4]. A linearized model is decomposed into three subsystems by means of linear transformation. Then the DMC based on such subsystem is designed. Simulation using Matlab-Simulink shows that the proposed algorithm works very well to the large step change of power demand.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2004.07a
• /
• pp.201-201
• /
• 2004

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.285-286
• /
• 2008

In this paper, we propose adaptive search channel estimate algorithm. The proposed algorithm is modified LMS algorithm which has a variable step size and parallel convolution. In simulation result, a error estimate accuracy of the proposed algorithm is about -20 dB and general LMS algorithm is about 10 dB. The proposed algorithm is better error estimate accuracy than general LMS algorithm.

• 제어로봇시스템학회:학술대회논문집
• /
• 1987.10b
• /
• pp.346-351
• /
• 1987

In this study, digital simulation with nonlinear modeling is carried out to analyse the performance of a hydraulic servomotor system developed for the position control of a large inertia. Nonlinear element, such as nonlinear pressure flow relationships of servovalve, valve spool limits, nonlinear friction, and backlash and resilience of gear system are included in the simulation along with the dynamic characteristics of variable delivery pump compensation mechanism. Simulation results are compared with experimental results for both step and sinusoidal inputs. Independent of input magnitude, both results are in good agreement with minor differences in detail.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.25 no.6
• /
• pp.614-628
• /
• 1988

In the original incremental Extended Horizon Control, the control inputs are computed recursively each step in the prediction horizon. But in this paper, we propose another incremental Extended Horizon Self-tuning Control version in which control inputs can be computed directly in any time interval. The effectiveness of this algorithm in a variable time delay or load disturbances environment is demonstrated by computer simulation. The controlled plant is a nonminimum phase system.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.26 no.9
• /
• pp.1420-1427
• /
• 1989

A new block matching algorithm that improved the existing block matching algorithm in terms of image quality is proposed in this paper. The subblock of image including the vertical edge of object is subdivided into new two subblocks, and the moving vector found. The result of computer simulation shows on real image that the image quality by the algorithm becomes higher than that of the three step search algorithm by 1.1dB.

• Journal for History of Mathematics
• /
• v.11 no.2
• /
• pp.1-7
• /
• 1998

Lee, Sang-Hyuk(1810-\ulcorner) said that Cha-Geun-Bang means algebra come from the West. In the chapter 'Che-Lyu' of the second volume of his book Cha-Geun-Bang-Mong-Gu, he gave the list of questions which could be expressed by the equation of one variable and explained the solution for them. All questions were formulated by equations of degree 2, 3, 4 which have terms on both sides of equal sign and they mostly have natural number solutions. The explanation of each question describes the procedure to make the equation in detail, but only presents the solution with few step to solve.