• 한국가시화정보학회지
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• 제17권2호
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• pp.48-57
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• 2019

A straightforward strategy for particle image velocimetry (PIV) interrogation and post-processing has been proposed, aiming at reducing errors and clarifying vortex structures. The interrogation window size should be kept small to reduce bias error and improve spatial resolution. A spatial filter is then applied to the velocity field to reduce random error and clarify flow structure. The performance of three popular spatial filters were assessed: box filter, median filter, and local quadratic polynomial regression filter. In order to quantify random uncertainty, the image matching (IM) method is applied to an experimental dataset of homogeneous and isotropic turbulence (HIT) obtained by 2D-PIV. We statistically analyze the uncertainty propagation through the spatial filters, and verify the reduction in random uncertainty. Moreover, we illustrate that the spatial filters help clarify vortex structures using vortex identification criteria. As a result, PIV random uncertainty was reduced and the vortex structures became clearer by spatial filtering.

• 정보처리학회논문지B
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• 제11B권6호
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• pp.709-716
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• 2004

최근에 인터넷과 통신망의 활성화로 인하여 특정 도메인 정보들을 효율적으로 구축하고 서비스하기 위한 여러 가지 방법들이 제안되고 있다. 본 논문에서는 멀티미디어 통계 사서함 구축을 위한 퍼지 필터링 객체 관련성 기법을 제안한다 제안된 기법은 S-cut을 이용하여 문서 객체들을 그룹화하기 위해 RelCRO( $D_{omain}$, Gi), RelSRO( $D_{omain}$, Gi), FAS를 이용한다. 또한 제안된 기법의 성능을 알아보기 위해 1600개의 멀티미디어 타입정보를 이용하여 실험을 수행하고 랜덤 키, OGM, 그리고 제안된 방법을 비교 분석한다. 그 결과 제안된 방법의 성능이 보다 효율적임을 보인다.

• 정보처리학회논문지B
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• 제8B권5호
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• pp.501-506
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• 2001

최근에 인터넷과 통신망의 활성화로 인하여 멀티미디어 정보들을 효율적으로 관리하고 서비스하기 위한 여러 가지 방법들의 제안되고 있다. 본 논문에서는 퍼지 기반의 멀티미디어 사서함 구축을 위한 객체관리기로서 $\alpha$-cut 을 이용한 FBOM을 제안한다. 제안된 시스템은 퍼지 필터링을 이용하여 객체들을 고나리하기 위해 객체 분류, 퍼지 필터링, 클래스 생성구조를 이용한다. 또한 제안된 시스템의 성능을 알아보기 위해 1000개의 멀티미디어 정보를 이용하여 실험을 수행하고, 랜덤 키 방법과 FBOM 방법을 비교 분석한다.

• Communications for Statistical Applications and Methods
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• 제19권1호
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• pp.147-155
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• 2012

We propose some properties for a fuzzy correlation test by reduced-spread fuzzy variance for sample fuzzy data. First, we define the condition of fuzzy data for repeatedly observed data or that which includes error term data. By using the average of spreads for fuzzy numbers, we reduce the spread of fuzzy variance and define the agreement index for the degree of acceptance and rejection. Given a non-normal random fuzzy sample, we have bivariate normal distribution by apply Box-Cox power fuzzy transformation and test the fuzzy correlation for independence between the variables provided by the agreement index.

• 정보과학회지
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• 제5권2호
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• pp.49-60
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• 1987

待期 理論(Queuing, waiting-Line Theory)은 例을 지어 待期하고 있는 現 象, 즉 各種 窓口에서 特定의 서어비스를 提供받기 위하여 個體가 기다리는 現象 에 관한 理論이며, 이와같은 理論的인 現象을 待期行列現象(Queuing phenomena, Waiting-Line phenomena)이라고 한다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2017년도 하계학술대회
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• pp.89-90
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• 2017

본 논문에서는 평균이동 (mean shift) 기법을 이용하여 랜덤포레스트 (random forest) 기반 실시간 얼굴 특징점 추적 (facial features tracking) 방법을 제안한다. 우선, 눈의 위치를 이용하여 검출된 얼굴영역을 적절한 크기와 위치로 개선하여 랜덤포레스트를 이용한 얼굴 특징점 추적 알고리즘이 받는, 얼굴검출 (face detection) 과정에 얻어지는 얼굴영역 상자 (face bounding box) 크기와 위치의 영향을 감소 하였다. 또한 랜덤포레스트의 얼굴 특징점 추정결과에서 추정평균 대신 평균이동기법을 이용하여 잘못된 추정결과들을 제거하고 제대로 된 추정결과만 사용하여 얼굴 특징점 검출 정확도를 개선하였다. 따라서 제안하는 방법들을 이용하여 기존의 랜덤포레스트 기반 얼굴 특징점 검출 기법의 성능을 제고하고 실시간으로 얼굴 특징점을 추적할 수 있다.

• 품질경영학회지
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• 제30권3호
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• pp.186-194
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• 2002

In this paper we introduce formulae for estimating the failure rate of a large scaled software by using the Bayesian rule when a black-box random testing which selects an element(test case) at random with equally likely probability, is performed. A program or software can be treated as a mathematical function with a well-defined (input)domain and range. For a large scaled software, their input domains can be partitioned into multiple subdomains and exhaustive testing is not generally practical. Testing is proceeding with selecting a subdomain, and then picking a test case from within the selected subdomain. Whether or not the proportion of selecting one of the subdomains is assumed probability, we developed the formulae either case by using Bayesian rule with gamma distribution as a prior distribution.

• 한국공작기계학회논문집
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• 제15권5호
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• pp.21-28
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• 2006

Vibration of a non-linear system with multiple degrees of freedom under random parametric excitations was evaluated by probabilistic method. The non-linear characteristic terms of system structure were quasi-linearized and excitation terms were remained as they were. An analytical method where the expectation values of square mean of error was minimized was used. The numerical results were compared with those obtained by Monte Carlo simulation. A linear congruential generator and Box-Muller method were used in Monte Carlo simulation. The comparison showed the results by probabilistic method agreed well with those by Monte Carlo simulation.

• 자원환경지질
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• 제29권4호
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• pp.523-528
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• 1996

In Korean topography the behaviors of random fractals and multifractality are analytically and numerically studied on the mountain heights shown between $128{\sim}129^{\circ}E$ and $37{\sim}38^{\circ}N$. The phase transitions on the fractal structure are approximately found at the critical length $N_c=2000m$ from the values of standard deviations that it varies with both the longitudinal and latitudinal lengths. In the multifractal structure we assume that the mountain heights divided by the intervals of 20 m are located on the horizontal plane in two dimensional square lattice, and estimate the values of the generalized dimension and the scaling exponents by using the the box counting method for the three cases of square area ($1{\times}1km^2$, $2{\times}2km^2$, $4{\times}4km^2$).

• Steel and Composite Structures
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• 제37권2호
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• pp.151-173
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• 2020

This paper aims to probabilistically evaluate performance of two types of I beam to box column (IBBC) connection. With the objective of considering the variability of seismic loading demand, statistical features of the inter-story drift ratio corresponding to the second, fifth and eleventh story of a 12-story steel special moment resisting frames are extracted through incremental dynamic analysis at global collapse state. Variability of geometrical variables and material strength are also taken into account. All of these random variables are exported as inputs to a probabilistic finite element model which simulates the connection. At the end, cumulative distribution functions of local seismic demand for each component of each connection are provided using histogram sampling. Through a parametric study on probabilistic local seismic demand, the influence of some geometrical random variables on the performance of IBBC connections is demonstrated. Furthermore, the probabilistic study revealed that IBBC connection with widened flange has a better performance than the un-widened flange. Also, a design procedure is proposed for WF connections to achieve a same connection performance in different stories.