• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.81-86
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• 2002

이전에 Magnetic Fluid를 이용하여 의료기기 등에 사용할 목적으로 Linear Actuator를 설계, 제작하였다. 그러나 이 모델은 공극의 높은 자기저항으로 인해 펌핑 압력이 낮고, 그 부피 또한 크다. 따라서 본 논문에서는 Yoke를 이용하여 Linear Actuator를 소형화하고 자기저항을 최소화함으로써 펌핑 압력을 향상시켰다. 또한 Linear Actuator의 3D해석을 통하여 Yoke의 폭, 두께, 간격에 대한 최적 크기를 계산하고 설계하였으며, 실제 제작 및 실험을 하였다.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.51-54
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• 1988

In this paper, Digital signal processing method is deserved by the tissue characteristic quantization. Linear phase velocity is studied using linear signal, and the slope which attenuation characteristics are decreased is analysed according to frequency increase. A more efficient method determining the minimum phase function is developed from the spectral magnitud function.

• The Journal of Korea Robotics Society
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• v.19 no.1
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• pp.8-15
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• 2024

This paper proposes a linear model predictive control of 6-DOF remotely operated underwater vehicles using nonlinear robust internal-loop compensator (NRIC). First, we design a integrator embedded linear model prediction controller for a linear nominal model, and then let the real model follow the values calculated through forward dynamics. This work is carried out through an NRIC and in this process, modeling errors and external disturbance are compensated. This concept is similar to disturbance observer-based control, but it has the difference that H_∞ optimality is guaranteed. Finally, tracking results at trajectory containing the velocity discontinuity point and the position tracking performance in the disturbance environment is confirmed through the comparative study with a traditional inverse dynamics PD controller.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.411-414
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• 2000

An ultrasonic linear motor was composed of a slider and a stator vibrator including piezoelectric material and elastic material. The ultrasonic linear motors mainly consist of an ultrasonic oscillator which generates elliptical oscillations. Elliptical oscillations are generated by synthesizing two degenerated modes. Direction of vibratory displacement was analyzed by employing the finite element method. So, we could recognize that the direction of the slider's movement was controlled by changing the Phase difference of the drive voltage.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1268-1270
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• 1987

This paper suggests several simple and efficient algorithms for detecting the ECG Signal by Microcomputer's software. The ECG signal detection was performed with the Linear Approximation and the feature extraction. The linear transformation approximates a given waveform by a piecewise-linear function with a preset upper bound on the absolute error between the functional values of the original function and the approximation. And the feature extraction from ECG signal, the features are different wave amplitudes, durations and interwave intervals, used the slope, the amplitude and time-Duration of ECG Sinal.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.6
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• pp.433-436
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• 2018

A total internal reflection (TIR) linear lens of size $190(W){\times}5(D){\times}2.1(H)mm^3$ has a directivity of $25^{\circ}$ and was made of a polydimethysiloxane (PDMS) silicone resin with a refractive index of 1.4 and a transmittance of 93% at 365 nm UV wavelength. A light source with a size of $190{\times}25.5mm^2$ was fabricated by installing a TIR linear lens on a chip on board (COB) type LED module mounted with a $1.1{\times}1.1mm^2$ size UV LED. The optical characteristics of the light source showed a maximum irradiation density of $3,840mW/cm^2$ at a working distance of 5 mm and a high uniformity of 91.6% over a $150{\times}25mm^2$ irradiation area. The thermal characteristics of the light source were measured at a supply current of 500 mA. The saturation temperature was reached after 30 min of operation, and measured to be $95^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.263-265
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• 2007

An ultrasonic linear motor using lambda shape vibrators has been designed and fabricated. The multiway ultrasonic motors mainly consist of an lambda shape ultrasonic vibrator which generates elliptical motions in beat. The lambda shape ultrasonic linear motor use longitudinal and bending vibration mode. In order to high precision motion control and multiway moving, piezoceramics were adhered to lambda shape brass elastic material. The finite element method was used to optimize dimension of ultrasonic vibrator and direction of vibratory displacement. As a result of estimating the characteristics of the ultrasonic linear motor, The results have shown that the lambda shape ultrasonic linear motor can be moved multiwav by using the phase control. Close agreement between the FEM results and experimental results obtained for the lambda shape ultrasonic linear motor.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.7
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• pp.587-591
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• 2013

This paper addresses the robust fault tolerant controller design problems of static output systems with disturbance. The fault is expressed by the abrupt chattering of system parameters. The design conditions are derived in terms of linear matrix inequalities and linear matrix equalities. An illustrative example is provided to verify performances of the proposed controller.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.11
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• pp.1231-1238
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• 2015

In this paper, we proposed an efficient algorithm using Node monitoring (NM) and Piecewise Linear Function Approximation(: NP) for reducing the complexity of LDPC code decoding. Proposed NM algorithm is based on a new node-threshold method together with message passing algorithm. Piecewise linear function approximation is used to reduce the complexity of the algorithm. This new algorithm was simulated in order to verify its efficiency. Complexity of our new NM algorithm is improved to about 20% compared with well-known methods according to simulation results.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.457-462
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• 2017

A linear carbon chain with pure sp hybridization has been intensively studied for the application of its intrinsic electrical properties to electronic devices. Owing to the high chemical reactivity derived from its unsaturated bond, encapsulation by carbon nanotubes (CNT) is provided as a promising method to stabilize the geometry of the linear carbon chain. Although the influence of CNT on the carbon chain has extensively been studied in terms of both electronic structure and geometries, the electron transport properties has not been discussed yet. In this regard, we provide the systematic atomic-scale analyses of the properties of the linear carbon chain within CNT based on a computational approach combining density-functional theory (DFT) and matrix green function (MGF) method. Based on the DFT calculations, the influence of CNT on electronic structures of the linear carbon chain is provided as well as its electrical origin. Via MGF calculations, we also identify the electron transport properties of the carbon chain - CNT complex.