http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
오승록,노신백,오승협 단국대학교 2000 論文集 Vol.35 No.-
We develop a practical equalization algorithm which can be used to improve data transmission rate and transmission error rate. The algorithm combines a blind method and a training method to estimate a communication channel. Since we use a blind method after training method processed, our algorithm improve data transmission rate and transmission error rate. For practical implmentation, we suggest an adaptive algorithm which can be used in real time applications such as a digital communication system. We demonstrate that our algorithm can reduce transmission error rate for an indoor wireless communication channel model through a simulation.
Seung-Rohk Oh(오승록),Hong-Jue Youn(윤홍주),Hyung-Seok Heo(허형석),Hyun-Jin Kim(김현진),ThienLuan Ho(호 티엔 루안) 대한전기학회 2015 정보 및 제어 심포지엄 논문집 Vol.2015 No.4
A parallel Aho-Corasick (AC) approach, named PAC-k, is proposed for the string matching in deep packet inspection (DPI). The proposed approach adopts graphic processing units (GPUs) to perform the string matching in parallel for high throughput. In the parallel string matching, the boundary detection problem happens when a pattern is matched across chunks. The PAC-k approach solves the boundary detection problem because the number of characters to be scanned by a thread is up to the longest pattern length. An input string is divided into multiple sub-chunks with k characters. By adopting the new starting position in each sub-chunk for the failure transition, the required number of threads is reduced by a factor of k. In addition, the number of terminated threads is decreased, computational resources are conserved. In order to avoid the unnecessary overlapped scanning with multiple threads, the checking module is proposed to decide whether a new starting position is in the sub-chunk. In the experiments with target patterns from Snort and realistic input strings from DEFCON, throughputs are enhanced greatly compared to those of previous AC-based string matching approaches.
Web Tension Control Using Output Feedback
Oh, Seung-Rohk Institute of Korean Electrical and Electronics Eng 2007 전기전자학회논문지 Vol.11 No.4
We consider a web transport system. The objective of this paper is to design the output feedback controller such that the controller can track a desired tension and processing speed on web transport system. We propose the new design method using observer and feedback linearization technique. The proposed method use a nonlinear feedback to transform to linear system and high gain observer to estimate the state value. We show that the proposed controller can achieve the control object using only output. We show a performance of controller via the simulation.
Adaptive Feedback Control for Minimum-phase Nonlinear System
Oh, Seung-rohk 단국대학교 1999 論文集 Vol.34 No.-
최소 위상 비선형 시스템에 대해 견실성이 있는 적응제어기를 설계하였다. 파라메타로 표현되는 불확실성은 적응제어 방법, 파라메타로 표현되지 않는 일반적인 불확실성은 가변구조제어 방법을 사용하여 좋은 성능을 보였다. 또한 폐루프에 대한 안정도를 분석하였고, 추적오차가 아주 적은 시스템의 설계 방법을 보였다.
Autotuning of A PID Controller Using a Saturation function Having a Memory
Oh, Seung-Rohk Institute of Korean Electrical and Electronics Eng 2007 전기전자학회논문지 Vol.11 No.4
We use a saturation function with memory instead of a pure saturation function to generate a limit cycle in order to find one point information of a plant in the frequency domain. The saturation function with memory is useful in the presence of noise and/or a short duration of short duration of external disturbances. We analyze the error caused by the approximation that the saturation function with memory treated as a pure saturation function. We propose a new tuning formula for PID controller which can be applied a saturation function having memory with an arbitrary memory size. We show that the proposed method is more accurate than that of the approximation method via an example.
PID Autotuning Algorithm with an Asymmetric Self-oscillation
오승록,Oh, Seung-Rohk Institute of Korean Electrical and Electronics Eng 2002 전기전자학회논문지 Vol.6 No.2
선형 플랜트의 극한 이득과 주기를 찾기 위해 포화함수를 이용하여 자기 진동을 발생 시켰다. 포화함수 사용으로 극한이득과 주기의 정확성을 높였다. 발견한 극한 이득과 극한 주기는 PID 제어기 값을 구하는데 사용하였다. 정적인 부하 왜란 등이 있는 경우 비대칭 진동이 발생할 수 있다. 발생하는 비대칭 자기 진동을 분석하였고 분석결과로부터 극한 이득과 주기를 찾는 방법을 제안하였다. We use the saturation nonlinear feedback element to generate self-oscillation in order to find an ultimate gain and period of linear plant. The use of saturation nonlinear feedback element can improve accuracy of an ultimate gain and period of unknown linear plant. An ultimate gain and period of linear plant can be used to tune a PID controller parameters. It is possible that an asymmetric oscillation can be occurred under the special circumstances such as with static load disturbance. We analyze an asymmetric self-oscillation. As the results of an analysis, we propose a method to find an ultimate gain and period of linear Plant under the asymmetric self-oscillation.
PID Autotuning Algorithm Based on Saturation Function Feedback
오승록,Oh, Seung-Rohk Institute of Korean Electrical and Electronics Eng 1998 전기전자학회논문지 Vol.2 No.2
릴레이 대신 포화함수를 이용하여 선형 플랜트의 극한 이득과 주기를 결정하였다. 포화함수를 사용함으로서 플랜트의 고주파 성분을 감소 시켜 묘사함수 사용에 의한 극한이득과 주기 결정의 정확도를 증가시켰다. 또한 적절한 포화함수를 사용할 수 있는 간단한 절차를 기술하였으며 진동이 발생하지 않는 플랜트에 대해서 지연요소를 이용한 자동동조 방법을 제시하였다. We use the slope bounded saturation nonlinear feedback element instead of relay to find ultimate gain and period of linear plant. Saturation nonlinear element reduces the high harmonics of plant output. The reduction of high harmonics improve the accuracy of describing function method used to find ultimate gain and period. We give a simple procedure to find ultimate gain and period with saturation nonlinear element. A PID controller design method with known time delay element is also given, which is very useful when oscillation is not occurred with nonlinear element.
가변 구조 제어 방식을 이용한 최소위상 비선형 시스템의 점근적 경로 추적
오승록,Oh, Seung-Rohk 한국전기전자학회 2009 전기전자학회논문지 Vol.13 No.1
입력 상수에 불확실성이 있는 최소위상 비선형시스템에 대해 경로추적 오차가 없는 제어기 설계를 제안하였다. 모델링 불확실성이 존재하는 비선형 시스템에 대해 상태 변수를 예측하기 위해 고 이득 관측기를 사용하였다. 적분형 가변 구조 제어 방식을 이용하여 점근적으로 경로추적오차가 0 되는 새로운 제어기를 제안하여 기존의 경로 추적오차를 감소시켰다. 제어기 설계의 정당성은 폐루프 시스템을 Lyapunov 분석 방법을 통해 보였다. 또한 제어기의 성능을 모의시험을 통해 보였다. A new controller which can achieve the asymptotic tracking is proposed for the nonlinear system having a uncertainty in the input coefficient. A high gain observer is used to estimate the state variables when the nonlinear system has a modeling uncertainty. A variable structure control is used to achieve an asymptotic tracking, while ultimate boundness was achieved in the previous work. A Lyapunov analysis is used to justify the our proposal. The performance of proposed method is demonstrated via simulation.
Two Time Scale Control Method of P-DEMO Fast Nuclear Reactor
Dina Puspitarini,오승록(Seung-Rohk Oh),황일순(Il-Soon Hwang) 대한전기학회 2010 정보 및 제어 심포지엄 논문집 Vol.2010 No.10
A singular perturbation method is applied to design a control system in P-DEMO fast nuclear reactor power plant. The basic concept of singular perturbation method is causing a multi-time-scale behavior of dynamic system characterized by the presence of both slow and fast transients in the system response to external stimuli. The controller is designed from the simplified fast nuclear reactor system model which has been approximated and changed into singular perturbation standard form. Optimal control design may then proceed for each lower order system. and the results combined to yield a composite control for the original system. This controller is simulated by MATLAB. singular perturbation, nuclear reactor power control, optimal control