• 한국인터넷방송통신학회논문지
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• 제18권2호
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• pp.105-110
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• 2018

본 논문에서는 NM-MMA (Novel Mixed-Multi Modulus Algorithm) 알고리즘에서 mixed 비용 함수를 얻기 위한 scaling factor값에 의한 적응 등화 성능을 비교하였다. NM-MMA의 mixed 비용 함수는 MMA와 SE-MMA 비용 함수에서 gradient vector를 적절한 scaling factor 가중치 합으로 구성되며, 이를 이용하여 탭 계수 갱신을 하므로서 기존 방식들의 수렴 속도와 MSE양을 개선할 수 있다. 논문에서는 scaling factor를 변화시킬 때 동일한 채널과 스텝 크기 및 신호대 잡음비의 환경에서 컴퓨터 시뮬레이션을 수행하여 등화기 출력 성상도, 잔류 isi, MD, MSE 및 SER 성능을 비교하였다. 컴퓨터 시뮬레이션의 결과 MMA 비용 함수의 가중치가 SE-MMA 비용 함수의 가중치보다 큰 경우에는 성능 지수의 잔여량에서 우월하며, 그 반대의 경우 수렴 속도가 개선됨을 확인하였다.

• 한국도로학회논문집
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• 제16권6호
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• pp.27-37
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• 2014

PURPOSES : The purpose of this study is to verify the causes of surface scaling at L-shoulder concrete structure. METHODS : From the literature reviews, mechanisms of frost damage were studied and material properties including strength, air void, spacing factor and scaling resistance of L-shoulder concrete structure were analyzed using core specimens taken by real fields. RESULTS : The spacing factor of air void has relatively high correlation of surface conditions : lower spacing factor at good surfacing condition and vice versa. If the compressive strength is high, even thought spacing factor does not reach the threshold value of reasonable durability, the surface scaling resistance shows higher value. Based on these test results, the compressive strength also provide positive effect on the surface scaling resistance. CONCLUSIONS : The main causes of surface scaling of L-shoulder could be summarized as unsuitable aid void amount and poor quality of air void structure. Secondly, although the compressive strength is not the governing factor of durability, but it shows the positive effect on the surface scaling resistance.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2807-2810
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• 2003

In this paper, we propose a fuzzy control method for improving the control performance by automatically tuning the scaling factor. The proposed method is that automatically tune the input scaling factor and the output scaling factor of fuzzy logic system through neural network. Used neural network is ADALINE (ADAptive Linear NEron) neural network with delayed input. ADALINE neural network has simple construct, superior learning capacity and small computation time. In order to verify the effectiveness of the proposed control method, we performed simulation. The results showed that the proposed control method improves considerably on the environment of the disturbance.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.177-177
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• 2000

In this paper, we propose a two-input two-output fuzzy controller to improve the performance of transient response and to eliminate the steady state error. The outputs of this controller are the control input calculated by position-type fuzzy controller and the accumulated error scaling factor. Here, the accumulated error scaling factor is adjusted on-line by fuzzy rules according to the current trend of the controlled process. To show the usefulness of the proposed controller, it is applied to several systems that are difficult to get satisfactory response by conventional PD controllers or PI controllers.

• 한국정보통신학회논문지
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• 제6권4호
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• pp.616-623
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• 2002

삼각형 마이크로스트립 패치를 기본으로 프랙털 확장시킨 삼각형 프랙털 안테나(Triangular Fractal Antenna)를 제안한다. TFA의 기본모드와 고차모드에 대한 공진주파수를 스케일링 인자 (scaling factor)를 변화시켜 조절한다. 스케일링 인자의 변화에 따라 공진주파수가 확산 혹은 집중되는 현상을 보인다. 각 프랙털 패치(fractal patch)에서 공진되는 주파수들은 대수 주기적으로 나타난다 이 논문에서 제안된 삼각형 프랙털 안테나는 다중대역 특성을 갖는 시스템에 적용 가능하다.

• 한국지구과학회지
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• 제37권5호
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• pp.277-285
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• 2016

We introduce a depth scaling strategy to improve the accuracy of frequency-domain elastic full waveform inversion (FWI) using the new pseudo-Hessian matrix for seismic data without low-frequency components. The depth scaling strategy is based on the fact that the damping factor in the Levenberg-Marquardt method controls the energy concentration in the gradient. In other words, a large damping factor makes the Levenberg-Marquardt method similar to the steepest-descent method, by which shallow structures are mainly recovered. With a small damping factor, the Levenberg-Marquardt method becomes similar to the Gauss-Newton methods by which we can resolve deep structures as well as shallow structures. In our depth scaling strategy, a large damping factor is used in the early stage and then decreases automatically with the trend of error as the iteration goes on. With the depth scaling strategy, we can gradually move the parameter-searching region from shallow to deep parts. This flexible damping factor plays a role in retarding the model parameter update for shallow parts and mainly inverting deeper parts in the later stage of inversion. By doing so, we can improve deep parts in inversion results. The depth scaling strategy is applied to synthetic data without lowfrequency components for a modified version of the SEG/EAGE overthrust model. Numerical examples show that the flexible damping factor yields better results than the constant damping factor when reliable low-frequency components are missing.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.416-418
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• 2006

In this paper, a new acoustic echo cancellation approach based on the DUET algorithm and scaling factor estimation is proposed to solve the scaling ambiguity in case of blind separation based acoustic echo cancellation in a noisy environment. In hands-free full-duplex communication system. acoustic noises picked up by the microphone are mixed with echo signal. For this reason, the echo cancellation system may provide poor performance. For that purpose, a degenerate unmixing estimation technique, adjusted in the time-frequency domain, is employed to separate undesired echo signals and noises. Also, since scaling and permutation ambiguities have not been solved in the blind source separation algorithm, kurtosis for the desired signal selection and a scaling factor estimation algorithm are utilized in this rarer for the separation of an echo signal. Simulation results demonstrate that the proposed approach yields better echo cancellation and noise reduction performances, compared with conventional methods.

• 한국정보통신학회논문지
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• 제16권9호
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• pp.2015-2020
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• 2012

본 연구에서는 이중게이트(Double Gate; DG) MOSFET에 스켈링이론을 적용할 때 두 개의 게이트에 의한 효과를 반영하기 위하여 스켈링인자에 가중치를 적용하여 문턱전압이하 특성을 해석하였다. 포아송방정식에 의한 전위분포를 구하기 위하여 전하분포는 가우스분포함수를 이용할 것이며 이의 타당성은 이미 여러 논문에서 입증하였다. 이 전위분포를 이용하여 단채널효과 중 문턱전압이동, 문턱전압이하 스윙, 드레인유도장벽감소 등을 스켈링인자에 대한 가중치의 변화에 따라 관찰하였다. 이중게이트 MOSFET의 구조적 특성상 채널길이에 대한 가중치는 0.1에서 1까지 사용하였으며 채널두께에 대한 가중치는 1에서 2까지 가중치를 사용하였다. 결과적으로 문턱전압 이하 스윙은 스켈링인자에 따라 거의 변화가 없었으나 가중치에 따라 변화하였으며 문턱전압이동 및 드레인유도 장벽감소 등은 스켈링인자에 따라 그리고 가중치에 따라 큰 변화를 보이는 것을 알 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.116.6-116
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• 2002

$\textbullet$ Concept of Adaptive Scaling Factor $\textbullet$ Initial Value and Boundary Conditions $\textbullet$ Adaptive Scaling Factor $\textbullet$ Simulation and Experimental Results

• Journal of Power Electronics
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• 제12권1호
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• pp.164-171
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• 2012

Variable step size maximum power point trackers (MPPTs) are widely used in photovoltaic (PV) systems to extract the peak array power which depends on solar irradiation and array temperature. One essential factor which judges system dynamics and steady state performances is the scaling factor (N), which is used to update the controlling equation in the tracking algorithm to determine a new duty cycle. This paper proposes a novel stability study of variable step size incremental resistance maximum power point tracking (INR MPPT). The main contribution of this analysis appears when developing the overall small signal model of the PV system. Therefore, by using linear control theory, the boundary value of the scaling factor can be determined. The theoretical analysis and the design principle of the proposed stability analysis have been validated using MATLAB simulations, and experimentally using a fixed point digital signal processor (TMS320F2808).