• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 1부
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• pp.623-628
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• 2008

본 논문에서는 비전 기반 게임 인터페이스를 위한 배경영역으로부터 전경영역을 추출하기 위해 빠르고 강건한 새로운 방법을 소개한다. Background Subtraction 방법은 추적하고자 하는 이미지의 특징을 추출하기 전에 필수적으로 거쳐야 하는 전처리 과정이다. 이를 위해 본 논문에서는 이미지를 지역 셀로 나누어 가우시안 커널이 적용된 Local Histogram을 계산하고 히스토그램의 Bhattacharyya 거리를 계산하여 전경확률을 결정한다. 이처럼 지역적 히스토그램에 기반한 방법은 급격한 조명변화나 잡음 또는 작은 배경오브젝트의 움직임에 부분적으로 강간함을 보인다. 히스토그램을 계산하는데에서 Multi-Scaled Integral Histogram을 사용하여 잡음을 억제하면서 계산의 속도를 높였다.

• 대한전자공학회논문지SP
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• 제47권4호
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• pp.112-118
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• 2010

본 논문에서는 시간지연신경회로망과 주파수영역의 파라미터를 가지는 선스펙트럼 쌍을 사용하여 정규화 방법에 기초한 잡음억제 시스템을 제안한다. 먼저, 시간지연신경회로망은 선형예측분석하여 구해진 잡음이 부가된 음성신호의 선스펙트럼 쌍을 학습시킨다. 그리고 제안한 시스템은 시간지연신경회로망을 학습시킴으로써 배경잡음에 의하여 열화된 잡음이 부가된 음성신호를 강조한다. 따라서 제안한 시간지연신경회로망은 학습에 의하여 잡음이 부가된 선스펙트럼 쌍의 값을 잡음이 부가되기 전의 값으로 복원하여 잡음을 억제한다. 제안한 시스템은 스펙트럼 왜곡율의 평가법을 사용하여 배경잡음에 의하여 열화된 음성 신호에 대하여 효과적인 것을 확인한다.

• 한국자기공명학회논문지
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• 제26권4호
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• pp.51-58
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• 2022

The baseline flattened NMR spectrum has been achieved by several methodologies including pulse manipulation with a series of phase cycling. The background signal inherent in the probe is also main source of baseline distortion both in solution and solid NMR. The simple direct polarization with 90° pulse flipping the magnetization from the z-axis onto the receiver coil requires the strong rf pulse enough to encompass the wide frequency range to excite the resonance of interest nuclei. Albeit the perfect polarization 90° pulse, the signal from the unwanted magnetic fields such as background signal can not be completely suppressed by suitable phase cycling. Moreover, slowly baseline wiggling signal from the low 𝛾 nuclei is not easy to eliminate with multiple pulse manipulation. So there is still need to contrive the new scheme for that purpose in an adroit manner. In this article new triple pulse excitation schemes for TIP and modified DEPTH pulse sequence are analytically examined in terms of arbitrary phase and flip angle of pulse. The suitable phase cycling for these pulse trains is necessary for the good sensitivity and resolution of the spectrum. It is observed that the ¹³C sensitivity TIP experiment is almost equal to the CP/MAS with modified DEPTH sequence, both of which are applicable to both solid and solution state NMR.

• 제어로봇시스템학회논문지
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• 제16권1호
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• pp.69-76
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• 2010

The segmentation of moving object in video sequence is a core technique of intelligent image processing system such as video surveillance, traffic monitoring and human tracking. A typical method to segment a moving region from the background is the background subtraction. The steps of background subtraction involve calculating a reference image, subtracting new frame from reference image and then thresholding the subtracted result. One of famous background modeling is Gaussian mixture model (GMM). Even though the method is known efficient and exact, GMM suffers from a problem that includes false pixels in ROI (region of interest), specifically shadow pixels. These false pixels cause fail of the post-processing tasks such as tracking and object recognition. This paper presents a method for removing false pixels included in ROT. First, we subdivide a ROI by using shape characteristics of detected objects. Then, a method is proposed to classify pixels from using histogram characteristic and comparing difference of energy that converts the color value of pixel into grayscale value, in order to estimate whether the pixels belong to moving object area or shadow area. The method is applied to real video sequence and the performance is verified.

• Journal of Information Processing Systems
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• 제14권6호
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• pp.1405-1419
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• 2018

An image fusion method is proposed on the basis of depth model segmentation to overcome the shortcomings of noise interference and artifacts caused by infrared and visible image fusion. Firstly, the deep Boltzmann machine is used to perform the priori learning of infrared and visible target and background contour, and the depth segmentation model of the contour is constructed. The Split Bregman iterative algorithm is employed to gain the optimal energy segmentation of infrared and visible image contours. Then, the nonsubsampled contourlet transform (NSCT) transform is taken to decompose the source image, and the corresponding rules are used to integrate the coefficients in the light of the segmented background contour. Finally, the NSCT inverse transform is used to reconstruct the fused image. The simulation results of MATLAB indicates that the proposed algorithm can obtain the fusion result of both target and background contours effectively, with a high contrast and noise suppression in subjective evaluation as well as great merits in objective quantitative indicators.

• IMMUNE NETWORK
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• 제4권4호
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• pp.237-243
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• 2004

Background: The normal functions of the cell cycle inhibitor p16INK4a are frequently inactivated in many human cancers. Over 80% of hepatocellular carcinoma (HCC) cases lack a functional p16/Rb pathway. p16/Rb pathway, as well as p53 pathway, is considered as one of key components of tumor suppression. Methods: To study the roles of p16INK4a in HCC, a stable cell line expressing exogenous p16 was generated from SNU-449 hepatocellular carcinoma cells lacking endogenous p16, and suppression subtractive hybridization (SSH) was performed in parallel with the control cells. Results: 1) SSH identifies fibronectin (FN1), crystallin ${\alpha}B$ (CRYAB), Rac1, WASP, RhoGEF, and CCT3 as differentially-expressed genes. 2) Among the selected genes, the up-regulation of FN1 and CRYAB was confirmed by Northern blot, RT-PCR and by proteomic methods. Conclusion: These genes are likely to be associated with the induction of stress fiber and stabilization of cytoskeleton. Further studies are required to clarify the possible role of p16 in the signal transduction pathway.

• 한방안이비인후피부과학회지
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• 제24권1호
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• pp.78-85
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• 2011

Background and Objectives : The aim of this study was to investigate anti-inflammatory and anti-oxidant effects of Hyunggaeyungyo-tang(HYT) on RAW 264.7 cells. Material and Methods : Two types of experiments were implemented for this study: first, the experiment to study the anti-oxidant effect of HYT using riboflavin; second, in vitro experiment to investigate the suppression of NF-${\kappa}$B activation using RAW 264.7 cells (I${\kappa}$B kinase and induce nitric oxide synthase mRNA expression) Results : 1. The anti-oxidant effects of HYT was dose-dependantly increased. 2. The RAW 264.7cells were treated with LPS for 1 hours prior to the addition of indicated concentrations(0.4,-1.0mg/$m\ell$) of HYT, and the cells were further incubated for 24 hours. The LPS-induced IKK & iNOS mRNA expression were dose-dependantly decreased in HYT treated RAW 264.7cells. Conclusion : The results suggest that HYT is significantly effective in the treatment of inflammation through the suppression of NF-${\kappa}$B activation and iNOS production.

• 한국음향학회지
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• 제31권3호
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• pp.179-187
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• 2012

This paper presents a novel method for estimating reliable noise spectral magnitude for acoustic background noise suppression where only a single microphone recording is available. The proposed method finds noise estimates from spectral magnitudes measured at line spectral frequencies (LSFs), under the observation that adjacent LSFs are near the peak frequencies and isolated LSFs are close to the relatively flattened valleys of LPC spectra. The parameters used in the proposed method are LPC coefficients, their corresponding LSFs, and the gain of LPC residual signals, so it suits well to LPC-based speech coders.

• The Korean Journal of Pain
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• 제11권1호
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• pp.23-29
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• 1998

Background: The present study was conducted to investigate effects of microinjection of bicuculline, GABA-A receptor antagonist, into the brain stem nuclei on the dorsal horn neuron responsiveness in rats with an experimental peripheral neuropathy. Methods: An experimental neuropathy was induced by a unilateral ligation of L5~L6 spinal nerves of rats. After 2~3 weeks after the surgery, single-unit recording was made from wide dynamic range (WDR) neurons in the spinal cord dorsal horn. Results: Responses of WDR neurons to both noxious and innocuous mechanical stimuli applied to the somatic receptive fields were enhanced on the nerve injured side. These enhanced responsiveness of WDR neurons were suppressed by microinjection of bicuculline into periaqueductal gray(PAG) or nucleus reticularis gigantocellularis(Gi). A similar suppression was also observed when morphine was microinjected into PAG or Gi. Suppressive action by Gi-bicuculline was reversed by naloxonazine, ${\mu}$-opioid receptor antagonist, microinjected into PAG whereas PAG-bicuculline induced suppression was not affected by naloxonazine injection into Gi. Gi-bicuculline induced suppression were reversed by a transection of dorsolateral funiculus(DLF) of the spinal cord. Conclusions: The results suggest that endogenous opioids, via acting on GABAergic interneurons in PAG and Gi, may be involved in the control of neuropathic pain by activating the descending inhibitory pathways that project to the spinal dorsal horn through DLF to inhibit the responsiveness of WDR neurons.

• 한국음향학회지
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• 제20권7호
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• pp.37-46
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• 2001

본 논문에서는 웨이블릿 변환을 이용한 주변 잡음제거기를 제안하였다. 기존의 고정된 시간-주파수 해상도를 가지는 단구간 푸리에 분석법 대신 다양한 시간-주파수 해상도를 제공하는 웨이블릿 분석법을 사용함으로써 시간 특성이 변하는 베이블 (Babble) 잡음에 좀더 효율적인 잡음제거 방법을 설계하였다. 본 논문에 제안된 웨이블릿 변환 잡음제거기는 스펙트럴 차감법에 기반하여 구성하였으며, 고주파 영역에서 높은 시간 해상도를 갖는 웨이블릿 마스크 패턴을 사용함으로써 시간 특성이 빠르게 변화하는 고주파 잡음에 더욱 효율적인 동작을 하도록 설계하였다. 성능평가를 위해 차량 잡음, 길거리 잡음, 베이블 잡음과 같은 이동통신에서 많이 사용하는 주변잡음에서 시험하였으며, 그 주관적 음질 평가 결과 베이블 잡음의 경우 기존의 EVRC(Enhanced Variable Rate Coder) 잡음 제거기보다 Mos (Mean Opinion Score) 0.2의 성능 개선을 이룰 수 있었다. 출력 음성의 스펙트로그램에서도 성능 개선을 확인할 수 있었다.