• 전자공학회논문지T
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• 제35T권3호
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• pp.87-95
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• 1998

본 논문에서는 시스템의 차수가 고차이며 잡음과 시간지연이 있고 시스템의 파라미터가 변하는 비최소위상 시스템에 적응할 수 있는 자기동조 제어기의 설계 하중다항식 계수를 온라인으로 조정하는 방법을 제안한다. 일반화 최소분산 자기동조 제어기의 설계 하중다항식 계수 값은 확률 근사법인 Robbins-Monro알고리즘을 이용하여 온라인으로 얻으며 자기동조 제어기의 파라미터는 순환최소자승법으로 추정하였다. 제안한 자기동조 제어 방법은 다른 자기동조 제어 방법들11.21보다 간단하고 효과적이다. 제어 알고리즘의 타당성을 확인하기 위해 일정한 시간이 경과한 후 시스템의 파라미터가 변하고 시스템의 영점이 단위원 밖에 있는 고차 시스템에 대해 컴퓨터 시뮬레이션을 하였다.

• 한국융합학회논문지
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• 제9권11호
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• pp.37-43
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• 2018

Science DMZ는 종단간 전송효율성 극대화를 위해 전용네트워크, DTN, 최소한의 보안정책과 같은 복합적인 요소를 고려한 네트워크 구조이다. 그리고 Science DMZ의 고대역폭의 전용네트워크를 충분히 활용하기 위해서는 DTN 튜닝이 필수적인 요소이다. 아울러 네트워크 병목구간으로 인한 패킷손실을 최소화하기 위해 네트워크 시스템의 튜닝이 병행적으로 수행되어야 한다. 본 논문에서는 Science DMZ 네트워크 구조에서 전송효율성 극대화를 위한 데이터 전송 노드 및 네트워크 시스템 튜닝 방안에 대해 제안한다. 국가과학기술연구망을 이용한 성능측정결과 DTN 튜닝 후 네트워크 성능이 튜닝을 하지 않을 것과 비교해 180% 성능향상을 보였다. 아울러 shaping 정책을 적용한 네트워크 시스템 튜닝 후 성능측정결과 손실 없이 9.4Gb/s의 성능을 보였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.1049-1053
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• 2002

An unconstrained tuning fork with a 3-D model has been numerically analyzed by Finite Element Method (FEM) and Boundary Element Method (BEM). The first three natural frequencies were calculated by the FEM modal analysis. Then the change of the modal frequencies was examined with the variation of the tuning fork length and width. Analytical model equations were derived from the numerically relating results of the modal frequency-tuning fork length by approximating minimization. Finally the BEM was used for the sound pressure field calculation from the structural displacement data.

• The Journal of the Acoustical Society of Korea
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• 제21권3E호
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• pp.112-118
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• 2002

An unconstrained tuning fork with a 3-D model has been numerically analyzed by Finite Element Method (FEM) and Boundary Element Method (BEM). The first three natural frequencies were calculated by the FEM modal analysis. Then the trend of the change of the modal frequencies was examined with the variation of the tuning fork length and width. An formula for the natural frequencies-tuning fork length relationship were derived from the numerical analysis results. Finally the BEM was used for the sound pressure field calculation from the structural displacement data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.265-268
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• 1992

The control performances of a fuzzy controller depend on its control rules, I/O membership functions, and scaling factors. Scaling factors are very important to adjust control parameters to the process which is to be controlled. For tuning the sealing factors, trial and error method is used in conventional fuzzy controller, which is very difficult and time consuming. This paper proposes a tuning method of scaling factors based on the concept of tuning rules for the conventional Pl controller parameters. The proposed automatic tuning fuzzy controller was evaluated by computer simulations. Good results have been obtained for the small hydro power plant.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1201-1204
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• 2003

An unconstrained tuning fork with a 3-D model has been numerically analyzed by Finite Element Method(FEM) and Boundary Element Method (BEM). The first three natural frequencies were calculated by the FEM modal analysis. Then the trend of the change of the modal frequencies was examined with the variation of the tuning fork length and width. An formula for the natural frequencies-tuning fork length relationship were derived from the numerical analysis results. Finally the BEM was used fur the sound pressure field calculation from the structural displacement data.

• International Journal of Computer Science & Network Security
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• 제24권2호
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• pp.196-202
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• 2024

Currently, the second most devastating form of cancer in people, particularly in women, is Breast Cancer (BC). In the healthcare industry, Machine Learning (ML) is commonly employed in fatal disease prediction. Due to breast cancer's favorable prognosis at an early stage, a model is created to utilize the Dataset on Wisconsin Diagnostic Breast Cancer (WDBC). Conversely, this model's overarching axiom is to compare the effectiveness of five well-known ML classifiers, including Logistic Regression (LR), Decision Tree (DT), Random Forest (RF), K-Nearest Neighbor (KNN), and Naive Bayes (NB) with the conventional method. To counterbalance the effect with conventional methods, the overarching tactic we utilized was hyperparameter tuning utilizing the grid search method, which improved accuracy, secondary precision, third recall, and finally the F1 score. In this study hyperparameter tuning model, the rate of accuracy increased from 94.15% to 98.83% whereas the accuracy of the conventional method increased from 93.56% to 97.08%. According to this investigation, KNN outperformed all other classifiers in terms of accuracy, achieving a score of 98.83%. In conclusion, our study shows that KNN works well with the hyper-tuning method. These analyses show that this study prediction approach is useful in prognosticating women with breast cancer with a viable performance and more accurate findings when compared to the conventional approach.

• 한국공작기계학회논문집
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• 제17권5호
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• pp.44-51
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• 2008

In this paper, the optimal tuning of a cross-coupled controller linked with the feedforward controller is studied to reduce contouring and tracking errors of a bi-axial servomechanisms by using the previously developed integrated tuning method. The CCC system for an arbitrary curve, which is combined with the feedforward controller, is formulated by a state-space based on a series of linear motion trajectories. An optimal tuning problem is formulated as a nonlinear constrained optimization problem including relevant controller parameters of the servo. To verify the effectiveness of the proposed optimal tuning procedure, linear and circular motion experiments are performed on the xy-table. Experimental results confirm that both tracking and contouring errors are significantly reduced by applying the proposed control and tuning system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2600-2605
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• 2003

The PBL (Poly-butadiene Latex) production process is a typical batch process. Changes of the reactor characteristics due to the accumulated scaling with the increase of batch cycles require adaptive tuning of the PID controller being used. In this work we propose a tuning method for PID controllers based on the closed-loop identification and the genetic algorithm (GA) and apply it to control the PBL process. An approximated process transfer function for the PBL reactor is obtained from the closed-loop data using a suitable closed-loop identification method. Tuning is performed by GA optimization in which the objective function is given by ITAE for the setpoint change. The proposed tuning method showed good control performance in actual operations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.628-631
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• 2005

In this paper, we propose tuning method of PID-PD controller to satisfy design specifications in frequency domain as well as time domain. The proposed tuning method of PID-PD controller that consist of the convex set of PID and PI-PD controller controls the closed-loop response to locate between the step responses, and Bode magnitudes of closed-loop transfer functions controlled by PID and PI-PD controller. The controller is designed by the optimum tuning method to minimize the proposed specific cost function subject to sensor noise insensitivity and robust stability. Its effectiveness is examined by the case study and analysis.