• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2000년도 추계학술대회 논문집
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• pp.62-68
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• 2000

The aim of the study was to compare effects of music and white noise on the recovery of facial blood flow parameters after stressful visual stimulation. Twenty-nine subjects participated in the experiment. Three visual stimulation sessions with aversive slides (the IAPS, disgust category) were followed by subjectively "pleasant" (in the first session), "sad" music (in the second ), and white noise (in the third ). Order of sessions was counterbalanced. Blood flow parameters (peak blood flow, blood flow velocity, blood volume) were recorded by Laser Doppler single-crystal system (LASERFLO BPM 403A) interfaced through BIOPAC 100WS with AcqKnowledge software (v.3.5) and analyzed in off-line mode. Aversive visual stimulation itself decreased blood flow and velocity in all 3 sessions. Both "pleasant" and "sad" music led to the restoration of baseline levels in all blood flow parameters, while noise did not enhance recovery process. Music on post-stress recovery had significant change in peak blood flow and blood flow velocity, but not in blood volume measures. Pleasant music had bigger effects on post-stress recovery in peak blood flow and flow velocity than white noise. It reveals that music exerted positive modulatory effects on facial vascular activity measures during recovery from negative emotional state elicited by stressful slides. Results partially support the undoing hypothesis of Levenson (1994), which states that positive emotions may facilitate process of recovery from negative emotions.

• 한국정보통신학회논문지
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• 제19권7호
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• pp.1687-1693
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• 2015

최근, 디지털 영상처리 장치에 대한 수요가 급격히 증대되면서 영상의 우수한 화질이 요구되고 있다. 그러나 디지털 영상을 획득, 처리, 전송하는 과정에서 여러 외부 원인에 의해 영상의 열화가 발생되고 잡음제거에 관한 연구가 대두되고 있다. 따라서 본 논문에서는 영상에 첨가되는 AWGN(additive white Gaussian noise)을 제거하기 위해, 3 × 3 마스크 내의 화소 분포에 따라 3개의 레벨로 나누어 처리하는 알고리즘을 제안하였다. 제안한 알고리즘은 AWGN (σ = 15)에 훼손된 Barbara 영상을 적용하여 처리한 결과, 기존의 MF(5 × 5), A-TMF(5 × 5), AWMF(5 × 5), MF (3 × 3), A-TMF(3 × 3), AWMF(3 × 3), GF(5 × 5)에 비해 각각 2.87[dB], 2.95[dB], 2.88[dB], 1.52[dB], 1.49[dB], 1.58[dB], 1.25[dB] 개선되었다.

• Journal of information and communication convergence engineering
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• 제6권1호
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• pp.80-85
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• 2008

Images are often corrupted by noises during signal acquisition and transmission. Among those noises, additive white Gaussian noise (AWGN) and impulse noise are most representative. For different types of noise have different characters, how to remove them separately from degraded image is one of the most fundamental problems. Thus, a modified image restoration algorithm is proposed in this paper, which can not only remove impulse noise of random values, but also remove the AWGN selectively. The noise detection step is by calculating the intensity difference and the spatial distance between pixels in a mask. To divide two different noises, the method is based on three weighted parameters. And the weighted parameters in the filtering mask depend on spatial distances, positions of impulse noise and standard deviation of AWGN. We also use the peak signal-to-noise ratio (PSNR) to evaluate restoration performance, and simulation results demonstrate that the proposed method performs better than conventional median-type filters, in preserving edge details.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.13-18
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• 2012

In this paper, we propose a noise estimation method for noise reduction. It is based on block and pixel-based noise estimation. We assume that an input image is contaminated by the additive white Gaussian noise. Thus, we use an adaptive Gaussian filter and estimate the amount of noise. It computes the standard deviation of each block and estimation is performed on pixel-based operation. The proposed algorithm divides an input image into blocks. This method calculates the standard deviation of each block and finds the minimum standard deviation block. The block in flat region shows well noise and filtering effects. Blocks which have similar standard deviation are selected as test blocks. These pixels are filtered by adaptive Gaussian filtering. Then, the amount of noise is calculated by the standard deviation of the differences between noisy and filtered blocks. Experimental results show that our proposed estimation method has better results than those by existing estimation methods.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권3호
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• pp.173-180
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• 2003

The modified Wiener filtering method is proposed for effective noise suppression in edge region of images corrupted by additive white gaussian noise. Although the pixels classified as a edge region in the conventional Wiener filter have lots of noise components, the conventional Wiener filler cannot remove noise effectively due to the preserving of edges. To reduce noise well in edge region, we modify filter coefficients of the conventional Wiener filter The modified filter coefficients increase in noise suppression effect In edge region, while they preserve edges for strong edge region. From simulation $(256{\time}256$ size, 256 graylevel images) filtered images by the proposed method show much improved subjective image quality with some improved peak signal-to-noise ratio compared to those by the conventional Wiener filtering.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권2호
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• pp.118-126
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• 2004

The modified Wiener filtering method is proposed for effective noise suppression in edge region of images corrupted by additive white gaussian noise. Although the pixels classified as a edge region in the conventional Wiener filter have lots of noise components, the conventional Wiener filter cannot remove noise effectively due to the preserving of edges. To reduce noise well in edge region, we modify filter coefficients of the conventional Wiener filter. The modified filter coefficients increase in noise suppression effect in edge region, while they preserve edges for strong edge region. From simulation (256${\times}$256 size, 256 graylevel images) filtered images by the proposed method show much improved subjective image quality with higher peak signal-to-noise ratio compared to those by the conventional Wiener filtering.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1996년도 춘계학술대회논문집; 부산수산대학교, 10 May 1996
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• pp.203-208
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• 1996

This paper consider the control for the vehicle suspension system using electro-rheological damper. The study is performed by using of FLC(Fuzzy Logic Controller). The model used in the simulation is quarter car and the road disturbance is regarded as white noise random process with zero mean. Proposed control technique shows good agreement compared with the result from the conventional on-off/bang-bang type control technique.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.1037-1040
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• 1988

In this study, we performed the recognition test on Korean vowel using peripheral auditory model. In addition, for the purpose of objective comparision, the recognition test is performed by extracting LPC cepstrum coefficients from the same data. And the same speech data are mixed with the Guaussian white noise quantitatively, then we repeated the same test, too. So we verified that this auditory model has a adaptability on noise.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.185-190
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• 2000

The sound absorption coefficient of glass wool (bulk density of 48 kg/$m^3$ and 32 kg/$m^3$) was measured by reverberation room method as varying their cross-sectional area. The results show that the absorption is larger for smaller samples because of edge effect. The absorption coefficient with two different kinds of sources, 1/3-octave band and white noise, gives similar values.

• Journal of Information Processing Systems
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• 제1권1호
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• pp.32-35
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• 2005

Image denoising is basic work for image processing, analysis and computer vision. This paper proposes a novel algorithm based on wavelet threshold for image denoising, which is combined with the linear CLS (Constrained Least Squares) filtering and thresholding methods in the transform domain. We demonstrated through simulations with images contaminated by white Gaussian noise that our scheme exhibits better performance in both PSNR (Peak Signal-to-Noise Ratio) and visual effect.