• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.111-114
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• 2019

This paper intends to implement a software that controls TurtleBot 2 remotely. The moving of the robot TurtleBot 2 can be controlled using command control based on Windows 10 IoT core instead of the Robot Operating System (ROS). The implemented software allows the user to move remotely TurtleBot 2 in any specified direction and perform the monitoring such as reading feedback data from the robot. Through TCP/IP and serial communication technology, TurtleBot 2 can successfully receive command control and send feedback to the user. Using C# programming language, two Universal Windows Platform apps (client app and server app) have been implemented to allow communication between the user and TurtleBot 2. The result of this implementation has been verified and tested in an indoor platform.

• 대한수학회지
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• 제61권3호
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• pp.565-602
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• 2024

We study the collective behaviors of two second-order nonlinear consensus models with a bonding force, namely the Kuramoto model and the Cucker-Smale model with inter-particle bonding force. The proposed models contain feedback control terms which induce collision avoidance and emergent consensus dynamics in a suitable framework. Through the cooperative interplays between feedback controls, initial state configuration tends to an ordered configuration asymptotically under suitable frameworks which are formulated in terms of system parameters and initial configurations. For a two-particle system on the real line, we show that the relative state tends to the preassigned value asymptotically, and we also provide several numerical examples to analyze the possible nonlinear dynamics of the proposed models, and compare them with analytical results.

• 대한전자공학회논문지SD
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• 제42권4호
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• pp.53-60
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• 2005

본 논문에서는 LCD 판넬 밝기의 균일성을 향상시키기 위하여 램프간의 저항 차이를 검출하는 회로를 사용한다. 기준 loop와 비교 loop의 feedback 전압을 나누어 검출된 저항의 차이는 PWM duty를 결정하는 제어 모드와 연결하여 램프 저항에 맞는 전압을 램프에 인가한다. 기준 loop의 feedback 전압은 모든 loop의 기준 전압이 되며, 하나의 IC에 램프의 수만큼 외부 기판을 연결하여 사용할 수 있다. 모든 비교 loop의 램프들은 기준 램프와 같은 밝기를 유지하기 위해 에러를 보상하며, 결과적으로 제안된 회로는 기존의 회로에 비해 약 $40\%$ 밝기 균일성을 재선한다.

• 대한기계학회논문집
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• 제11권6호
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• pp.923-934
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• 1987

본 연구에서는 유연한 로봇 조각기를 허브가 있는 첨단질량이 부착된 유연한 외팔보로 모델링하고 Hamilton의 원리에 의하여 유도된 운동방정식을 Galerkin의 모우 드 합 방접을 이용하여 유한차원화하여 상태방정식으로 표시하였다. 계를 제어 모우 드부(controlled mode part)와 잔류 모우드부(residual mode part)로 나누어 제어 모 우드부에 대해 최적제어 이론을 도입하여 귀환계수(feedback ccefficient)를 구하였으 며 측정이 불가능한 상태변수(inaccessible state)를 근사적으로 추정하기 위하여 Lu- enberger 관측기가 사용되었다.2차 성능계수(quadratic performance index)내의 입 력에 대한 가중치의 변화에 따른 제어효과 및 계의 여러 모우드중 중요 모우드만 제어 하는 제어기를 사용함에 따른 Spillover 효과가 계의 제어효과에 미치는 영향을 시뮬 레이션을 통하여 고찰하였으며, 또한 실험을 통하여 이론의 타당성을 검토하였다.

• Journal of Power Electronics
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• 제13권5호
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• pp.829-840
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• 2013

The modified sinusoidal pulse-width modulation (SPWM) is one of the PWM techniques used in three-phase AC-DC buck converters. The modified SPWM works without the current sensor (the converter is current sensorless), improves production of sinusoidal AC current, enables obtainment of near-unity power factor, and controls output voltage through modulation gain (ranging from 0 to 1). The main problem of the modified SPWM is the huge starting current and voltage (during transient) that results from a large step change from the reference voltage. When the load changes, the output voltage significantly drops (through switching losses and non-ideal converter elements). The single-input single-output (SISO) approach with minor-loop voltage feedback controller presented here overcomes this problem. This approach is created on a theoretical linear model and verified by discrete-model simulation on MATLAB/Simulink. The capability and effectiveness of the SISO approach in compensating start-up current/voltage and in achieving zero steady-state error were tested for transient cases with step-changed load and step-changed reference voltage for linear and non-linear loads. Tests were done to analyze the transient performance against various controller gains. An experiment prototype was also developed for verification.

• International Journal of Aeronautical and Space Sciences
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• 제11권4호
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• pp.285-302
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• 2010

Active aeroelastic control is an emerging technology aimed at providing solutions to structural systems that under the action of aerodynamic loads are prone to instability and catastrophic failures, and to oscillations that can yield structural failure by fatigue. The purpose of the aeroelastic control among others is to alleviate and even suppress the vibrations appearing in the flight vehicle subcritical flight regimes, to expand its flight envelope by increasing the flutter speed, and to enhance the post-flutter behavior usually characterized by the presence of limit cycle oscillations. Recently adaptive and robust control strategies have demonstrated their superiority to classical feedback strategies. This review paper discusses the latest development on the topic by the authors. First, the available control techniques with focus on adaptive control schemes are reviewed, then the attention is focused on the advanced single-input and multi-input multi-output adaptive feedback control strategies developed for lifting surfaces operating at subsonic and supersonic flight speeds. A number of concepts involving various adaptive control methodologies, as well as results obtained with such controls are presented. Emphasis is placed on theoretical and numerical results obtained with the various control strategies.

• 간호행정학회지
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• 제13권2호
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• pp.242-253
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• 2007

Purpose: The aim of this study is to examine the effectiveness of an computer-tailored intervention program to promote breast-feeding. Method: A quasi-experimental design was used assigning forty pregnant women to the experimental group (computer-tailored intervention condition) and the control group (no-intervention control condition). Thirty-three participants completed pretest and posttest questionnaires and 19 participants assigned to intervention condition received personal feedback tailored by computer program. Result: Participants in the experimental group showed higher mean score of 'perception of the importance of breast-feeding'. Significant differences in internal health locus of control was found between the participants in the experimental group and the control group. Participants in the experimental group exceeded controls on intention of breast-feeding. Participants in the control group more often felt that the length of program contents they received was somehow longer. Conclusions: The use of a computer-tailored intervention improved the perception of the importance of breast-feeding and the internal health locus of control. The intention of breast-feeding was increased through the personal feedback tailored by computer even though participants felt that the length of program contents of tailored feedback was not longer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.986-989
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• 1988

The new controller which conststs of IBM-PC/AT, SBC, servo module and motor driver has been developed for KIMMBOT II robot. The servo module which controls two axes at the same time also has beendeveloped. This module inputs relative number of pulse and feedrate via multbus, after then outputs analog command voltage with reference to feedback pulses from the encoder of a motor. This system has a great flexibility. The reduction of parts gives more reliability.

• 대한수학회지
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• 제35권1호
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• pp.135-148
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• 1998

We propose the new controls constructed via the second or direct method of Liapunov to solve the collision avoidance control problems for moving objects and a robot arm in the plane. We also explicate the controlling effect by the simulations.

• 정보보호학회논문지
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• 제1권1호
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• pp.66-78
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• 1991

본 논문에서는 스트림 암호시스템의 종류와 오류전파 특성에 대해 분석한다. 또한, 암호문 전송중 전송로상에서 발생하는 오류르 제어할 목적으로 DSEC(31, 27) RS 부호를 암호문 귀환암호시스템에 내부오류제어 및 외부오류제어로 분류하여 적용하고 오류정정과정을 분석한다.