• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.559-562
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• 2003

A motion-based background subtraction method without geometric computation is proposed, allowing that the camera is moving parallel to the ground plane with uniform velocity. The proposed method subtracts the background region from a given image by evaluating the difference between calculated and model Hows. This approach is insensitive to small errors of calculated optical flows. Furthermore, in order to tackle the significant errors, a strategy for incorporating a set of optical flows calculated over different frame intervals is presented. An experiment with two real image sequences, in which a static box or a moving toy car appears, to evaluate the performance in terms of accuracy under varying thresholds using a receiver operating characteristic (ROC) curve. The ROC curves show, in the best case, the figure-ground segmentation is done at 17.8 ％ in false positive fraction (FPF) and 71.3％ in true positive fraction (TPF) for the static-object scene and also at 14.8％ in FPF and 72.4％ In TPF for the moving-object scene, regardless if the calculated optical flows contain significant errors of calculation.

• Nuclear Engineering and Technology
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• v.38 no.1
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• pp.99-108
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• 2006

SNU-RCCS is a water pool type RCCS (Reactor Cavity Cooling System) developed for VHTR (Very High Temperature Reactor) application by SNU (Seoul National University). Since radiation heat transfer is the major process of passive heat removal in a RCCS, it is important to determine the precise emissivity of the reactor vessel. Review studies have used a constant emissivity in the passive heat removal analysis, even though the emissivity depends on many factors such as temperature, surface roughness, oxidation level, wavelength, direction, atmosphere conditions, etc. Therefore, information on the emissivity of a given material in a real RCCS is essential in order to properly analyze the radiation heat transfer in a VHTR. The objectives of this study are to develop a method for compensation of the factors affecting the emissivity measurement using an infrared thermometer and to estimate the true emissivity from the measured emissivity via the developed method, especially in the SNU-RCCS environment. From this viewpoint, we investigated factors such as the attenuation effect of the window, filling gas, and the effect of background radiation on the emissivity measurements. The emissivity of the vessel surface of the SNU-RCCS facility was then measured using a sight tube. The background radiation was subsequently removed from the measured emissivity by solving a simultaneous equation. Finally, the calculated emissivity was compared with the measured emissivity in a separate emissivity measurement device, yielding good agreement with the emissivity increase with vessel temperature in a range of 0.82 to 0.88.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.131-138
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• 1989

In this paper the feature of background EEG is extracted by LS Prony Method for the analysis of background EEG in the time domain. Autocorrelation leg estimates are not required with the LS Prony method. The Prony method is required any the solution of two serfs of simultaneous linear equation and a polynominal rooting. That the optimal order of this model is the 6-th order is determined by using Akaike' s Information Criterial test. From the experimential results the alpha band amplitude is the largest among alpha band beta band theta band delta band and beta band amplitude is larger than that of the delta band and theta band. The sustained time for the alph a band, the beta band, the delta band and the theta band is 2, 3461 (sec), 0.6490(sec), 0.3120(sec), 0.7046(sec) respectively. Consequenty the alpha band is maintained in the whole subjects, the beta band, the delta band, the theta band are existed intermittently in each subjects.

• Journal of architectural history
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• v.11 no.3 s.31
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• pp.87-103
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• 2002

In contemporary architecture, there are developing aspects of variety design in material, image and form. These various architectural trends even change classical media and this concept is based on the background of current idea - digital, information-media, imagination with paradigm. So this study aims to show the present status of the expressions in the contemporary architecture of Korea under its media situation. Namely usual thoughts for design have to be changed because our life is surrounded by many kinds of powerful media signs and various mixed cultural circumstances. And like this, we know for study about the relation between media and current architecture, still more Korean present condition. In chapter one, the background, purpose and method of study are explained. In chapter two, the general concept of media is inquired in this study. In the process of searching for the formingbasic background, the characteristic of this study is understood. In chapter three, this study inquires the aspect of media expression in modern architecture. In chapter four, according to chapter three, this study shows the present status of media expressions in the contemporary architecture of Korea. In chapter five, a synthetic conclusion is presented.

• Journal of architectural history
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• v.11 no.1 s.29
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• pp.7-19
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• 2002

Contemporary architecture is developing aspects of variety design in form and material. The various architectural trends even change classical materiality. This concept has the background of current idea - digital, information, imagination with paradigm. So this study aims to show the present status of the expressions in the contemporary architecture in Korea under its dematerialized situation. And like this, we know for study about the relation between dematerialization and current architecture, still more Korean present condition. In chapter one, the background, purpose and method of study are explained. In chapter two, this study inquires the general concept of dematerial. In the process of searching for the forming basic background this study understands the characteristic. In chapter three, this study inquires the aspect of dematerialized expression in modern architect. In chapter four, with characteristics drawn in chapter three, this study show the present status of the expressions in the contemporary architecture in Korea under its dematerialized situation. In chapter five, a synthetic conclusion is presented.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.4
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• pp.56-64
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• 2000

The design of filters for pattern recognition that have optimal trade-off for the criteria of noise robustness, peak sharpness and Homer efficiency, when input scene noise is spatially disjoint (nonoverlapping) with the target, are presented Three different criteria, ie, signal-to-noise ratio, peak-to-output energy ratio and light efficiency are used to design the filter. Computer simulation is made for the various types of noise and parameters to illustrate filter performance for optical pattern recognition. When we compare the new trade-off filter with the original optimal trade-off filter, the performance of trade-off filter for nonoverlapping background is better than that of trade-off filter for overlapping background.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.599-604
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• 2008

The dispersive phase velocity of a wave propagating through a system is an important parameter and carries valuable information in non-destructive tests related to multilayered systems such as a soil site. The dispersive phase velocity of a wave can be determined using the phase spectrum, which is easily evaluated through the cross power spectrum. However, the phase spectrum as determined using the cross power spectrum is sensitive to background noise which always exists in the field. This causes difficulties in the determination of the dispersive phase velocities. In this paper, a new method to evaluate the phase spectrum using the harmonic wavelet transform is proposed. The proposed method can successfully remove background noise effects. To evaluate the validity of the proposed method, numerical simulations of multi-layered systems were performed. Phase spectrums by the proposed method were found to be in good agreement with the actual phase spectrums under conditions characterized by heavy background noise. This shows the potential of the proposed method.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.28-30
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• 2009

This paper describes a 3-DTIP(3-D Tour Into Picture) using depth map for a Korean classical painting being composed of persons and landscape. Unlike conventional TIP methods providing 2-D image or video, our proposed TIP can provide users with 3-D stereoscopic contents. Navigating inside a picture provides more realistic and immersive perception. The method firstly makes depth map. Input data consists of foreground object, background image, depth map, foreground mask. Firstly we separate foreground object and background, make each of their depth map. Background is decomposed into polygons and assigned depth value to each vertexes. Then a polygon is decomposed into many triangles. Gouraud shading is used to make a final depth map. Navigating into a picture uses OpenGL library. Our proposed method was tested on "Danopungjun" and "Muyigido" that are famous paintings made in Chosun Dynasty. The stereoscopic video was proved to deliver new 3-D perception better than 2-D video.

• Journal of Korea Multimedia Society
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• v.17 no.4
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• pp.420-432
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• 2014

In detection of moving objects from video sequences, an essential process for intelligent visual surveillance, the cast shadows accompanying moving objects are different from background so that they may be easily extracted as foreground object blobs, which causes errors in localization, segmentation, tracking and classification of objects. Most of the previous research results about moving cast shadow detection and removal usually utilize color information about objects and scenes. In this paper, we proposes a novel cast shadow removal method of moving objects in gray level video data for visual surveillance application. The proposed method utilizes observations about edge patterns in the shadow region in the current frame and the corresponding region in the background scene, and applies Laplacian edge detector to the blob regions in the current frame and the corresponding regions in the background scene. Then, the product of the outcomes of application determines moving object blob pixels from the blob pixels in the foreground mask. The minimal rectangle regions containing all blob pixles classified as moving object pixels are extracted. The proposed method is simple but turns out practically very effective for Adative Gaussian Mixture Model-based object detection of intelligent visual surveillance applications, which is verified through experiments.

• The Journal of the Acoustical Society of Korea
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• v.38 no.6
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• pp.697-702
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• 2019

We propose a multi-band multi-scale DenseNet with dilated convolution that separates background music signals from broadcast content. Dilated convolution can learn the multi-scale context information represented by spectrogram. In computer simulation experiments, the proposed architecture is shown to improve Signal to Distortion Ratio (SDR) by 0.15 dB and 0.27 dB in 0dB and -10 dB Signal to Noise Ratio (SNR) environments, respectively.