• The Journal of the Acoustical Society of Korea
• /
• v.14 no.3
• /
• pp.28-36
• /
• 1995

In this paper, a double loop control model using leaky delay LMS algorithm are proposed for active noise control. The proposed double loop control model estimates the loudspeaker characteristic and the error path transfer function with on-line using only gain and acoustic time delay to reduce computation burden. The control of error signal through double loop control scheme makes the more robust cntrol system. The input signal of filter to estimate acoustic time delay is used difference between input signal of input microphone and adaptive filter output. And also, in nonstationary environments, the leaky delay LMS algorithm is employed to counteract parameter drift of delay LMS algorithm. For practical noise signal, the proposed double loop control model reduces noise level about 12.9 dB.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.2 no.2
• /
• pp.35-40
• /
• 1997

The hysteresis control method has been frequently used for current control of power conversion equipments or motor drive systems. This method makes the measured signal follow the reference signal by changing the control signal whenever the error signal exceeds the preset band width. In this paper, hysteresis control method with fast response characteristics is applied for active noise control to suppress acoustic noise. Both Pentium processor and sound blaster 16 are used for experimental implementation, which executes A/D, D/A conversion and also is used as operating source of loudspeaker for audible noise cancellation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.241-243
• /
• 2016

In the Past, Trend of car security was Physical Something like doorlock system, and The Generation did not have skills connecting External devices. Through Car Development is up, that trend of car security Changed Physical Security to Intelligence Security. This Changes give a chance to hackers to attack this system. This System use CAN(Controller Area Network) Protocol which have three vulnerabilities. First, ID Spoofing, Twice, D - Dos Attack, Third, Android Application Injected Modern cars have many ECU(Electronic Control Unit) to control devices like Engine ON/OFF, Door Lock Handling, and Controlling Handle. Because CAN Protocol spread signal using broadcast, Hackers can get the signal very easily, and Those often use Mobile devices like Android or IOS to attack this system. if bluetooth signal is spread wide, hackers get the signal, and analysis the bluetooth data, so then They makes certain data to attack ECU, they send the data to ECU, and control ECU installed car. so I suggest that I will prevent this attack to make Auth system and prevent this attack in end of Android.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2016.07a
• /
• pp.123-124
• /
• 2016

본 논문에서는 사물인터넷 기법을 원격지에서 재배환경을 제어할 수 있는 온실 원격제어시스템을 제안한다. 온실원격제어시스템은 온실내의 환경정보를 계측하여 서버에 저장하고, 이 정보를 이용하여 사용자가 제어함으로서 최적의 재배환경으로 조절하고, 저장된 재배 환경정보를 활용하여 작물의 최적의 재배를 위한 기초 자료로 활용하도록 한다. 온실 원격 제어시스템을 웹과 연동하여 각종 기기를 이용하여 원격으로 제어함으로서 각 사용자들이 온실에 접근하지 않고 원격으로 환경을 제어할 수 있도록 구성하였다. 온실 원격제어시스템은 제어부, 통신부 그리고 계측부로 구성하였으며, 무선인터넷을 통하여 5초마다 제어신호를 확인하여 처리하고, 온도를 측정하여 서버에 저장하여 동작을 확인하였다. 따라서 본 논문에서 제안하는 온실 원격제어시스템은 최적의 생장환경을 지속적으로 제공하여 농가의 생산 효율성을 증대 시킬 수 있으리라 사료된다.

• Journal of Astronomy and Space Sciences
• /
• v.24 no.4
• /
• pp.349-366
• /
• 2007

We designed and developed a multi-purpose CCD camera system for three kinds of CCDs; KAF-0401E($768{\times}512$), KAF-1602E($1536{\times}1024$), KAF-3200E($2184{\times}1472$) made by KODAK Co.. The system supports fast USB port as well as parallel port for data I/O and control signal. The packing is based on two stage circuit boards for size reduction and contains built-in filter wheel. Basic hardware components include clock pattern circuit, A/D conversion circuit, CCD data flow control circuit, and CCD temperature control unit. The CCD temperature can be controlled with accuracy of approximately $0.4^{\circ}C$ in the max. range of temperature, ${\Delta}33^{\circ}C$. This CCD camera system has with readout noise $6\;e^-$, and system gain $5\;e^-/ADU$. A total of 10 CCD camera systems were produced and our tests show that all of them show passable performance.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.10
• /
• pp.1197-1205
• /
• 2014

Recently signal transmission of ultra high-definition(4K-UHD) video system is transferred as uncompressed high speed data. However, this has a limit to compose the system because EMI between separate cables of high speed interface section and skew bring distortion of the video signal and jitter. In this paper we applied V-by-One HS interface technique to transfer uncompressed high speed data. We analyzed HSD(High Speed Differential) transmission line signal integrity. Also we applied RF transmission technique instead of UHD video pattern control interface PCB design. When we measured V-by-One HS video signal of designed 4K-UHD class signal generator, We found that the transmission performance has been signal standard.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.184-187
• /
• 2007

본 논문은 DSP Controller를 적용한 연료전지시스템의 유량제어에 관한 논문이다. 그리고 이 연구에서 사용된 시스템은 1kW급 계통연계 연료전지 시스템이다. 이 연료전지 시스템이 안정적으로 전원을 공급할 수 있도록 시스템에서 요구하는 공기 유량을 정확히 공급하도록 제어하는 것이 본 연구의 목적이다. 이 목적을 이루기 위해 공기 공급 장치에 PID 제어기를 설계하여 적용하였다. PID 제어기의 Gain값은 지글러 니콜스 Tuning 방식으로 정하였다. 이 제어기를 적용하여 실험한 결과, 적용 전 상태와 비교하면 맥동이 30% 저감하였고, 정상상태 오차가 제거되어 온도 변화와 같은 외란과 상관없이 정확한 요구 공기 유량을 공급함을 확인할 수 있었다. 그리고 부하가 변동함에 따라 해당 요구 공기 유량이 바뀔 때 1초 내에 그 요구 공기 유량을 추종하여 스택이 안정적으로 운전될 수 있도록 하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.10 no.4
• /
• pp.100-106
• /
• 2011

Radio Frequency (RF) signal fluctuates dynamically in wireless communication environments, where this fluctuation is severe especially in vehicular environments. Automatic Gain Control (AGC) is critical in wireless communications to establish reliable communication links and compensate the received signal fluctuation. In this paper, we introduce a simple and novel AGC scheme which uses both Received Signal Strength Indicator (RSSI) and analog-to digital converter (ADC) signals. Performance enhancement of the proposed AGC scheme is verified with practical measurements including simulations.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.319-320
• /
• 2022

본 논문에서는 내부 네트워크를 사용하여 여러 로봇들을 동시에 혹은 각각 제어할 수 있는 시스템을 제안한다. 이 시스템은 모바일, 데스크탑을 통해 원하는 로봇들을 다중 제어하고, 나아가서는 PJ link를 통한 프로젝터 제어, WOL을 통한 데스크탑 제어, 아두이노 레오나르도를 통한 키보드, 마우스 제어 등 여러 통합 컨트롤 시스템을 구축할 수 있다. 와이파이를 통한 시리얼 통신으로 esp8266과 컨트롤 pc 간의 통신이 이루어지고, I2C 통신을 통해 esp8266에서 레오나르도로 신호를 주어 다른 pc를 제어할 수 있다. 로봇의 경우에는 esp8266을 통해 직접적으로 제어가 가능하며 원하는 개수의 로봇을 동시에 혹은 각각 제어할 수 있다. 이러한 통합 컨트롤 시스템을 통해 여러 기기의 로봇을 보다 수월하게 제어가능하며 로봇뿐만 아니라 여러가지 기기들을 한번에, 수월하게 컨트롤 할 수 있게 된다.

• Journal of the Institute of Convergence Signal Processing
• /
• v.8 no.2
• /
• pp.119-123
• /
• 2007

This paper investigates a speed sensorless control of induction motor. The control strategy is based on MRAS(Model Reference Adaptive System) using load-torque observer as a reference model for flux estimation. The speed response of conventional MRAS controller characteristics is affected by variations of load torque disturbance. In the proposed system, the speed control characteristics using a load-torque observer control isn't affected by a load torque disturbance. Control algorithm that propose whole system through MATLAB SIMULINK because do modelling simulation result are presented to prove the effectiveness of the adaptive sliding mode controller for the drive variable load of induction motor. Therefore we hope to be extended in industrial application.