• Title/Summary/Keyword: exact

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Semantic Process Retrieval with Similarity Algorithms (유사도 알고리즘을 활용한 시맨틱 프로세스 검색방안)

  • Lee, Hong-Ju;Klein, Mark
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2007.11a
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    • pp.267-272
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    • 2007
  • One of the roles of the Semantic Web services is to execute dynamic intra-organizational services including the integration and interoperation of business processes. Since different organizations design their processes differently, the retrieval of similar semantic business processes is necessary in order to support inter-organizational collaborations. Most approaches for finding services that have certain features and support certain business processes have relied on some type of logical reasoning and exact matching. This paper presents our approach of using imprecise matching fur expanding results from an exact matching engine to query the OWL MIT Process Handbook. In order to use the MIT Process Handbook for process retrieval experiments, we had to export it into an OWL-based format. We model the Process Handbook meta-model in OWL and export the processes in the Handbook as instances of the meta-model. Next, we need to find a sizable number of queries and their corresponding correct answers in the Process Handbook. We devise diverse similarity algorithms based on values of process attributes and structures of business processes. We perform retrieval experiments to compare the performance of the devised similarity algorithms.

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The Effects of Different Cross Section on Natural Frequency of the Advanced Composite Materials Road Structures (복합신소재 도로구조물의 변환단면이 고유진동수에 미치는 영향)

  • Han, Bong Koo
    • International Journal of Highway Engineering
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    • v.15 no.3
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    • pp.23-29
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    • 2013
  • PURPOSES: This paper aims to give a guideline and the way to apply the advanced composite materials theory to the road structures with different cross sections to the practicing engineers. METHODS: To simple but exact method of calculating natural frequencies corresponding to the modes of vibration of road structures with different cross sections and arbitrary boundary conditions. The effect of the $D_{22}$ stiffness on the natural frequency is rigorously investigated. RESULTS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. CONCLUSIONS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. This method is a simple but exact method of calculating natural frequencies of the road structures with different cross sections. This method is extended to be applied to two dimensional problems including composite laminated road structures.

DEFAULT BAYESIAN INFERENCE OF REGRESSION MODELS WITH ARMA ERRORS UNDER EXACT FULL LIKELIHOODS

  • Son, Young-Sook
    • Journal of the Korean Statistical Society
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    • v.33 no.2
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    • pp.169-189
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    • 2004
  • Under the assumption of default priors, such as noninformative priors, Bayesian model determination and parameter estimation of regression models with stationary and invertible ARMA errors are developed under exact full likelihoods. The default Bayes factors, the fractional Bayes factor (FBF) of O'Hagan (1995) and the arithmetic intrinsic Bayes factors (AIBF) of Berger and Pericchi (1996a), are used as tools for the selection of the Bayesian model. Bayesian estimates are obtained by running the Metropolis-Hastings subchain in the Gibbs sampler. Finally, the results of numerical studies, designed to check the performance of the theoretical results discussed here, are presented.

Design of Unknown-Input PI Observer and Realization of Exact LTR (미지입력 비례적분 관측기 설계와 완전 LTR의 실현)

  • ;S. KAWAJI
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.7
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    • pp.133-139
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    • 1996
  • 전형적인 상태 관측기에서는, 외란이 시스템 입력에 가해지는 경우 시스템의 상태 추정이 불가능하다. 이러한 상태관측 문제에 대한 한가지 대책법으로서 비례적분(PI) 관측기가 제안되어 스텝외란의 소거에 대한 유효성이 밝혀져 로바스트 제어기 설계에 대한 응용으로서 널리 연구가 행해져 왔다. 그러나, 미지입력에 대한 PE 관측기 설계는 여전히 문제로 남아 있다. 이 논문에서는 미지입력 PI 관측기의 설계법을 제안하고, 이에 대한 응용으로서 완전 LTR을 실현할 수 있는 결과를 보인다. 먼저, 입력의 정보없이 시스템의 상태를 추정할 수 있는 미지입력 PI 관측기의 충분조건을 제안하고, PE 관측기의 설계에 요구되는 필요충분조건을 보인다. 이러한 조건은 완전 LTR의 실현을 위한 직접적인 요구조건임을 보인다. 따라서, 완전 LTR을 달성하면서 지정한 관측기의 극을 지니는 PI 관측기 설계가 가능하다.

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An efficient modeling method for open cracked beam structures (열린 균열이 있는 보의 효율적 모델링)

  • Kim, M.D.;Choi, S.H.;Hong, S.W.;Lee, C.W.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.725-730
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    • 2002
  • This paper presents an efficient modeling method for open cracked beam structures. An equivalent bending spring model is introduced to represent the structural weakening effect in the presence of open cracks. The proposed method adopts the exact dynamic element method (EDEM) to avoid the difficulty and numerical errors in association with re-meshing the structure. The proposed method is rigorously compared with a commercial finite element code. Experiments are also performed to validate the proposed modeling method. Finally, a diagnostic scheme for open cracked beam structures is proposed and demonstrated through a numerical example.

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Dynamics of an Axially Moving Timoshenko Beam (축 방향으로 이동하는 티모센코보의 동특성 해석)

  • Kim, Joo-Hong;Oh, Hyung-Mi;Lee, U-Sik
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.1066-1071
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    • 2002
  • The use of frequency-dependent spectral element matrix (or exact dynamic stiffness matrix) in structural dynamics is known to provide very accurate solutions, while reducing the number of degrees-of-freedom to resolve the computational and cost problems. Thus, in the present paper, the spectral element model is formulated for the axially moving Timoshenko beam under a uniform axial tension. The high accuracy of the present spectral element is then verified by comparing its solutions with the conventional finite element solutions and exact analytical solutions. The effects of the moving speed and axial tension on the vibration characteristics, the dispersion relation, and the stability of a moving Timoshenko beam are investigated, analytically and numerically.

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Exact Algorithms of Transforming Continuous Solutions into Discrete Ones for Bit Loading Problems in Multicarrier Systems

  • Chung, Yong-Joo;Kim, Hu-Gon
    • Management Science and Financial Engineering
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    • v.16 no.3
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    • pp.71-84
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    • 2010
  • In this study, we present the exact methods of transforming the continuous solutions into the discrete ones for two types of bit-loading problem, marginal adaptive (MA) and rate adaptive (RA) problem, in multicarrier communication systems. While the computational complexity of existing solution methods for discrete optimal solutions depends on the number of bits to be assigned (R), the proposed method determined by the number of subcarriers (N), making ours be more efficient in most cases where R is much larger than N. Furthermore our methods have some strength of their simpler form to make a practical use.

An Improved Exact Algorithm for the Unconstrained Two-Dimensional Cutting Problem (개수 제한이 없는 2차원 절단문제를 위한 향상된 최적해법)

  • Gee, Young-Gun;Kang, Maing-Kyu
    • Journal of Korean Institute of Industrial Engineers
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    • v.27 no.4
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    • pp.424-431
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    • 2001
  • This paper is concerned with the unconstrained two-dimensional cutting problem of cutting small rectangles (products), each of which has its own profit and size, from a large rectangle (material) to maximize the profit-sum of products. Since this problem is used as a sub-problem to generate a cutting pattern in the algorithms for the two-dimensional cutting stock problem, most of researches for the two-dimensional cutting stock problem have been concentrated on solving this sub-problem more efficiently. This paper improves Hifi and Zissimopoulos's recursive algorithm, which is known as the most efficient exact algorithm, by applying newly proposed upper bound and searching strategy. The experimental results show that the proposed algorithm has been improved significantly in the computational amount of time as compared with the Hifi and Zissimopulos's algorithm.

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An Improved Best-First Branch and Bound Algorithm for Unconstrained Two-Dimensional Cutting Problems (무제한 2차원 절단문제에 대해 개선된 최적-우선 분지한계 해법)

  • Yoon Ki-Seop;Bang Sung-Kyu;Kang Maing-Kyu
    • Journal of the Korean Operations Research and Management Science Society
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    • v.30 no.4
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    • pp.61-70
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    • 2005
  • In this Paper, we develop an improved branch and bound algorithm for the (un)weighted unconstrained two-dimensional cutting problem. In the proposed algorithm, we improve the branching strategies of the existing exact algorithm and reduce the size of problem by removing the dominated pieces from the problem. We apply the newly Proposed definition of dominated cutting pattern and it can reduce the number of nodes that must be searched during the algorithm procedure. The efficiency of the proposed algorithm is presented through comparison with the exact algorithm known as the most efficient.

Exact stochastic solution of beams subjected to delta-correlated loads

  • Falsone, G.;Settineri, D.
    • Structural Engineering and Mechanics
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    • v.47 no.3
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    • pp.307-329
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    • 2013
  • The bending problem of Euler-Bernoulli discontinuous beams is dealt with, in which the discontinuities are due to the loads and eventually to essential constrains applied along the beam axis. In particular, the loads are modelled as random delta-correlated processes acting along the beam axis, while the ulterior eventual discontinuities are produced by the presence of external rollers applied along the beam axis. This kind of structural model can be considered in the static study of bridge beams. In the present work the exact expression of the response quantities are given in terms of means and variances, thanks to the use of the stochastic analysis rules and to the use of the generalized functions. The knowledge of the means and the variances of the internal forces implies the possibility of applying the reliability ${\beta}$-method for verifying the beam.