• 대한수학회지
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• 제36권1호
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• pp.139-157
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• 1999

Consider a supercritical Bellman-Harris process evolving from one particle. We superimpose on this process the additional structure of movement. A particle whose parent was at x at its time of birth moves until it dies according to a given Markov process X starting at x. The motions of different particles are assumed independent. In this paper we show that when the movement process X is standard Brownian the proportion of particles with position $\leq${{{{ SQRT { t} }}}} b and age$\leq$a tends with probability 1 to A(a)$\Phi$(b) where A(.) and $\Phi$(.) are the stable age distribution and standard normal distribution, respectively. We also extend this result to the case when the movement process is a Levy process.

• Structural Engineering and Mechanics
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• 제62권6호
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• pp.675-693
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• 2017

In this paper, based on the first-order shear deformation plate theory, buckling analysis of piezoelectric coupled transversely isotropic rectangular plates is investigated. By assuming the transverse distribution of electric potential to be a combination of a parabolic and a linear function of thickness coordinate, the equilibrium equations for buckling analysis of plate with surface bonded piezoelectric layers are established. The Maxwell's equation and all boundary conditions including the conditions on the top and bottom surfaces of the plate for closed and open circuited are satisfied. The analytical solution is obtained for Levy type of boundary conditions. The accurate buckling load of laminated plate is presented for both open and closed circuit conditions. From the numerical results it is found that, the critical buckling load for open circuit is more than that of closed circuit in all boundary and loading conditions. Furthermore, the critical buckling loads and the buckling mode number increase by increasing the thickness of piezoelectric layers for both open and closed circuit conditions.

• 한국유통학회:학술대회논문집
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• 한국유통학회 1997년도 유통학술대회 논문집
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• pp.121-139
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• 1997

전통적인 마케팅 기능이 제품에 대한 구매 욕구를 창조하는 기능, 즉 제품 소유 효용을 창출하는 반면에 물류(logistics)는 시간 및 장소 효용을 창출하므로써 제품 소유 효용을 가능하게 만드는 중요한 부가가치 창출기능이라는 인식이 증가하고 있다. 특히 품질과 가격이 비슷한 경쟁적인 성숙시장에서는 오히려 차별적 우위의 물류서비스 제공을 통해 고객만족을 시킬 수 있기 때문에 물류서비스가 지속적인 경쟁우위 개발을 위한 무기가 될 수 있다(Sharma, Grewal, and Levy 1995). (중략)

• Structural Engineering and Mechanics
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• 제28권4호
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• pp.373-386
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• 2008

In this study stochastic analysis of non-linear dynamical systems under ${\alpha}$-stable, multiplicative white noise has been conducted. The analysis has dealt with a special class of ${\alpha}$-stable stochastic processes namely sub-Gaussian white noises. In this setting the governing equation either of the probability density function or of the characteristic function of the dynamical response may be obtained considering the dynamical system forced by a Gaussian white noise with an uncertain factor with ${\alpha}/2$- stable distribution. This consideration yields the probability density function or the characteristic function of the response by means of a simple integral involving the probability density function of the system under Gaussian white noise and the probability density function of the ${\alpha}/2$-stable random parameter. Some numerical applications have been reported assessing the reliability of the proposed formulation. Moreover a proper way to perform digital simulation of the sub-Gaussian ${\alpha}$-stable random process preventing dynamical systems from numerical overflows has been reported and discussed in detail.

• Journal of the Korean Statistical Society
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• 제30권3호
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• pp.481-498
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• 2001

Empirical Bayes procedure of nonparametric estiamtion of cumulative hazard rates based on censored data is considered using the beta process priors of Hjort(1990). Beta process priors with unknown parameters are used for cumulative hazard rates. Empirical Bayes estimators are suggested and asymptotic optimality is proved. Our result generalizes that of Susarla and Van Ryzin(1978) in the sensor that (i) the cumulative hazard rate induced by a Dirichlet process is a beta process, (ii) our empirical Bayes estimator does not depend on the censoring distribution while that of Susarla and Van Ryzin(1978) does, (iii) a class of estimators of the hyperprameters is suggested in the prior distribution which is assumed known in advance in Susarla and Van Ryzin(1978). This extension makes the proposed empirical Bayes procedure more applicable to real dta sets.

• 공학교육연구
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• 제14권3호
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• pp.61-71
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• 2011

Korea has introduced the levy-grand system in the vocational learning finance. The standard unit price system of training cost was utilized in the distribution of training budget and the reimbursement system including total or partial training cost return has been operated in the corporate training after completing the learning course particularly. The standard unit price was calculated in the base of analyzing on supporting budget by the government per training institutions and corporate payment decision to learning institutions. The proposing standard unit price system of training cost was analyzed in the current standard price unit of training cost and then an improvement policy and the implication are derived from it. At the result of this study, the current government supporting level to e-learning and postal distance learning indicates good status.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제3권12호
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• pp.523-530
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• 2014

온톨로지 정렬의 목적은 지식을 공유 및 재사용 하는 데 있다. 기존 온톨로지 정렬 시스템은 온톨로지 개념의 모호성 때문에 여러 가지 다양한 측정 기법을 사용하고 전수조사를 수행하여 사용자가 만족하는 결과를 얻는다. 온톨로지 개념이 점차 많아짐에 따라 계산이 복잡해지고 걸리는 시간이 기하급수적으로 증가하여 처리 과정에서 오류가 발생한다. 이를 해결하기 위하여 메타 휴리스틱 알고리즘을 사용하는 메타 매칭이 연구되고 있다. 기존 메타 매칭 시스템에서는 사용하는 파라미터가 많기 때문에 온톨로지 정렬 처리에 계산이 복잡하고 특정 도메인의 다양한 데이터에 따라 조율이 요구되어 온톨로지 정렬 탐색에 좋은 성능을 보여주지 못했다. 이 논문에서는 온톨로지 정렬을 쉽고 간단한 계산을 통해 높은 성능을 목표로 하여 DCS(Discrete Cuckoo Search) 를 사용한 온톨로지 정렬 알고리즘을 제안한다. 제안한 알고리즘은 Levy Flight 분포에 따른 탐색으로 효율적인 전략을 보여준다. 제안된 알고리즘은 OAEI 2012(Ontology Alignment Evaluation Initiative)에서 제공하는 벤치마크 데이터와 제안 알고리즘을 사용하여 성능을 평가한다.

• Computational Structural Engineering : An International Journal
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• 제1권1호
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• pp.49-57
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• 2001

This paper presents exact solutions for the modal stress-resultant distributions for vibrating rectangular Mindlin plates involving two opposite sides simply supported while the other two sides free. These exact stress-resultants of vibrating plates with free edges, hitherto unavailable, are very important because they serve as benchmark solutions for checking numerical solutions and methods. Using the exact solutions of a square plate, this paper highlights the problem of determining accurate stress-resultants, especially the transverse shear forces and twisting moments in thin plates, when employing the widely used numerical methods such as the Ritz method and the finite element method. Thus, this study shows that there is a need for researchers to develop refinements to the Ritz method and the finite element method for determining very accurate stress-resultants in vibrating plates with free edges.

• Structural Engineering and Mechanics
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• 제4권5호
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• pp.541-552
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• 1996

This paper is concerned with the structural optimization problem of maximizing the compressive buckling load of orthotropic rectangular plates for a given volume of material. The optimality condition is first derived via variational calculus. It states that the thickness distribution is proportional to the strain energy density contrary to popular claims of constant strain energy density at the optimum. An engineers physical meaning of the optimality condition would be to make the average strain energy density with respect to the depth a constant. A double cosine thickness varying plate and a double sine thickness varying plate are then fine tuned in a one parameter optimization using the Rayleigh-Ritz method of analysis. Results for simply supported square plates indicate an increase of 89% in capacity for an orthotropic plate having 100% of its fibers in $0^{\circ}$ direction.

• 전기전자학회논문지
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• 제28권2호
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• pp.187-198
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• 2024

Estimating the phase boundary in two-phase flow is crucial for designing and optimizing industrial processes. Electrical impedance tomography (EIT) is a promising technique for imaging phase distribution in such flows. This paper proposes using a cuckoo search (CS) optimization algorithm to estimate the phase boundary with EIT. The boundary is parameterized using the Fourier series, and the coefficients are determined by the CS algorithm. The CS algorithm iteratively seeks the phase boundary configuration by minimizing a cost function. Computer simulations and phantom experiments demonstrate the effectiveness of this method in estimating phase boundaries in two-phase flow.