• 한국전산유체공학회지
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• 제4권3호
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• pp.12-20
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• 1999

The computations of the flowfield and pollutant dispersion over a flat plate and the Russian hills of various slopes are described. The Gaussian plume and the puff model have been used to calculate concentration of pollutant. The Reynolds-averaged unsteady incompressible Navier-Stokes equation with low Reynolds κ-ε model has been used to calculate the flowfield. The flow data of a flat plate and the Russian hills from Navier-Stokes equation solutions has been used as the input data for the puff model. The computational results of flowfield agree well with experimental results of both a flat plate and Russian hills. The concentration prediction by the Gaussian plume model and the Gaussian puff model also agrees flirty well with experiments.

• 비파괴검사학회지
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• 제25권3호
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• pp.163-170
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• 2005

A modular Gaussian beam model is developed to simulate some ultrasonic testing configurations where multiple interfaces are involved. A general formulation is given in a modular matrix form to represent the Gaussian beam propagation with multiple interfaces. The ultrasonic transducer fields are modeled by a multi-Gaussian beam model which is formed by superposing 10 single Gaussian beams. The proposed model, referred to as "MMGB" (modular multi-Gaussian beam) model, is then applied to a typical contact and angle beam testing configuration to predict the output signal reflected from the corner of a vertical crack. The resulting expressions given in a modular matrix form are implemented in a personal computer using the MATLAB program. Simulation results are presented and compared with available experimental results.

• Nuclear Engineering and Technology
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• 제17권3호
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• pp.216-223
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• 1985

원자력 발전소로부터 방출되는 기체상 방사성 물질에 의한 환경 영향을 평가함에 있어서 방사성 물질의 대기중에서의 수송과 확산을 기술하는 모델로써 Gaussian plume mode띠 널리 사용되고 있다. Gaussian plume model은 평탄한 지형에 적용하도록 만들어진 모델이므로 대부분의 국토가 복잡한 산악으로 구성된 한극의 경우에 적용하기 위해서는 모델의 수정이 필요하다. 본 논문에서는 2차원적 x-ｚ 평면에서 확산방정식을 해석한 numerical diffusion model과 Gaussian plume model을 비교하여, Gaussian plume mode에서 가장 중요한 변수인 dispersion coefficient를 지형의 높이에 대하여 보정하였다. 보정된 dispersion coefficient 값을 Gaussian plume mode에 적용시켜 계산을 수행한 결과를 보면, 산악지역에서의 방사성 물질의 농도는 평지에서보다 낮게 나타나고 있다.

• 한국전자통신학회논문지
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• 제7권4호
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• pp.733-739
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• 2012

본 논문에서는 시간과 기후에 따라 변화하는 영상의 밝기와 색상 변화에도 강건한 연기검출 알고리즘을 제안한다. 제안하는 연기검출 알고리즘은 입력영상과 배경영상의 차영상을 이용하여 후보영역을 설정하고, 후보영역 차영상의 Gaussian 혼합모델 특징 계수를 비교하여 연기를 판별한다. 시간과 기후에 대응하기 위하여 입력영상의 평균 밝기와 색상을 기준으로 후보영역 설정을 위한 임계값을 4 단계로 구분한다. 후보영역에 대한 차영상의 Gaussian 혼합모델의 밝기 평균값을 기준으로 클러스터를 정렬하고, 클러스터 간의 Gaussian 혼합모델 특징 계수를 비교하여 연기를 판별한다. 제안하는 알고리즘을 미디어전용 DSP로 구현하고 야외에 설치된 카메라의 영상에 대하여 연기검출 실험을 통하여 효율적으로 연기를 검출할 수 있음 보인다.

• Communications for Statistical Applications and Methods
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• 제20권5호
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• pp.395-404
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• 2013

This paper studies the skewness of the absolute value GARCH(1, 1) models with Gaussian mixture innovations (Gaussian mixture AVGARCH(1, 1) models). The maximum estimated-likelihood estimator (MELE) employed (a two- step estimation method in order to estimate the skewness of Gaussian mixture AVGARCH(1, 1) models. Through the real data analysis, the adequacy of adopting Gaussian mixture innovations is exhibited in reflecting the skewness of two major Korean stock indices.

• Journal of the Korean Statistical Society
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• 제25권4호
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• pp.515-527
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• 1996

It has been known for mean field models that the limiting distribution reflecting the asymptotic behavior of the system is non-Gaussian at the critical state. Recently, however, Papangelow showed for the critical Curie-Weiss mean field model that there exist Gaussian structures in the asymptotic behavior of the total magnetization. We construct Gaussian structures existing in the internal fluctuation of the system for the critical case of a generalized Curie-Weiss mean field model.

• Journal of the Optical Society of Korea
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• 제19권4호
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• pp.363-370
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• 2015

The current waveform model of a laser altimeter is based on a Gaussian laser beam of fundamental mode, while the flattened Gaussian beam has many advantages such as nearly constant energy distribution on the center of the cross-section. Following the theory of the flattened Gaussian beam and the waveform theory of the laser altimeter, some of the primary parameters of the received waveform were derived, and a laser altimetry waveform simulator and waveform processing software were programmed and improved under the circumstance of a flattened Gaussian beam. The result showed that the bias between theoretical and simulated waveforms was less than 3% for every order mode, the waveform width and range error would increase as target slope or order number rose. Under higher order mode, the shapes of the received waveforms were no longer Gaussian, and could be fitted more precisely as a generalized Gaussian function with power bigger than 2. The flattened beam got much better performance for a multi-surface target, especially when the small surface is far from the center of the laser footprint. This article provides the waveform theoretical basis for the use of a flattened Gaussian beam in a laser altimeter.

• 응용통계연구
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• 제28권2호
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• pp.353-360
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• 2015

공간적으로 관측되는 연속형 자료를 분석하는 모형으로 공간적 상관관계를 고려한 다양한 정규모형이 지난 수십 년간 제안되었다. 그 중에서 공간효과를 랜덤효과로 모형화하는 공간선형모형(Spatial Linear Mixed Model; SLMM)이 가장 널리 활용되는 모형 중 하나일 것이다. 연결함수(link function)을 사용하면 SLMM을 비정규 데이터도 적용할 수 있는 일반화된 공간선형모형(Spatial Generalized Linear Mixed Model; SGLMM)으로 자연스럽게 확장할 수 있다. 이 논문에서는 가장 널리 활용되는 SGLMM을 알아보고 실제 데이터 적용사례를 R 패키지를 활용하여 제시하고자 한다.

• 대한전자공학회논문지
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• 제25권6호
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• pp.654-662
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• 1988

A simple and useful model of light distribution for the biologhical tissue to the Gaussian beam is proposed. This model assumes that the incident Gaussian beam broadens into two Gaussian beams, travelling in the opposite directions as the result of both isotropic scattering and absorption in the tissue. With this assumption, two-dimensional light intensity of each flux as well as the equations of both absorption and scattering have been derived, and the validity of modeling has been confirmed experimentally. Consequently, the results paved a way for easy evaluation of the light distribution in the biological tissue.

• 경영과학
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• 제26권1호
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• pp.161-169
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• 2009

A traffic analysis on the Internet has an advantage for obtaining the characteristics of transferred packets. There were many studies to understand the characteristics of the Internet traffic with mathematical statistical approach. The approach of this study is different from previous studies. We first introduced a virtual network concept to present the Internet as a simplified mathematical model. It also represents each traffic flowing on the Internet as a parallel Gaussian channel on the virtual network. We suggest the optimal capacity of each parallel Gaussian channel using some related studies on the Gaussian channel model.