• Title/Summary/Keyword: Theoretical Computation

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A Theoretic Foundation of Imprecise Computation (근사값 계산 방안에 대한 이론적 연구)

  • Park, Dong-Won
    • The Journal of Natural Sciences
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    • v.7
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    • pp.115-120
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    • 1995
  • Imprecise computation has been suggested as a promising model of real-time computing in order to deal with timing constraints imposed by the environment. However, the theoretical foundation of the technique has not been fully explored. To address this, a decision-theoretic foundation of imprecise computation is proposed. The main benefit of such a treatment is that it enables the qualitative assumptions underlying imprecise computation techniques to be explicitly stated in a formal way. The theoretical foundation laid out in this paper, hence, will not only enable the justification of using imprecise computation techniques for a real-time application, but will also facilitate the development of extended techniques for more complexs real-time systems.

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Optimal O/D Sample Size Computation using link Volume Estimates (구간 교통량의 표준오차를 이용한 최적 O/D 표본수 산출)

  • 윤성순;김원규
    • Journal of Korean Society of Transportation
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    • v.12 no.1
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    • pp.75-84
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    • 1994
  • In this paper we address the issue of how an optimal sample size computation relates the level of precision required for travel demand estimations and transportation planning. We approach the problem by 1) deriving a theoretical solution, 2) developing a computational procedure (algorithm) to implement the theoretical solution, and 3) demonstrating a practical application. Ultimately, we construct a formal scheme of optimal sample size computation for use in travel data collection processe.

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Evaluations of Representations for the Derivative of Rational $B\{e}zier$ Curve (유리 $B\{e}zier$ 곡선의 미분계산방법의 평가)

  • 김덕수;장태범
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.4
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    • pp.350-354
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    • 1999
  • The problem of the computation of derivatives arises in various applications of rational Bezier curves. These applications sometimes require the computation of derivative on numerous points. Therefore, many researches have dealt with the representation for the computation of derivatives with the small computation error. This paper compares the performances of the representations for the derivative of rational Bezier curves in the performances. The performance is measured as computation requirements at the pre-processing stage and at the computation stage based on the theoretical derivation of computational bound as well as the experimental verification. Based on this measurement, this paper discusses which representation is preferable in different situations.

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Computation of Spring Constants of MEMS Socket Pins by Theoretical Analysis (이론분석에 의한 MEMS 소켓 핀의 스프링 상수 계산)

  • Bae, Kyoo-Sik;Ho, Kwang-Il
    • Korean Journal of Materials Research
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    • v.18 no.11
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    • pp.592-596
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    • 2008
  • Spring constants (displacement per unit applied load) of MEMS socket pins of given structures were computed by theoretical analysis and confirmed by the finite element method (FEM). In the theoretical analysis, the displacement of pins was calculated based on the 2-dimensional bending theory of the curved beam. For the 3-dimensional modeling, CATIA was used. After modeling, the raw data were transferred to ANSYS, which was employed in the 3-dimensional analysis for the calculation of the stress and strain and loaddisplacement The theoretical analysis and the FEM results were found to agree, with each showing the spring constants as 63.4 N/m within a reasonable load range. These results show that spring constants can be easily obtained through theoretical calculation without resorting to experiments and FEM analysis for simple and symmetric structures. For the some change of shape and structural stiffness, this theoretical analysis can be applied to MEMS socket pins.

Robust and Efficient 3D Model of an Electromagnetic Induction (EMI) Sensor

  • Antoun, Chafic Abu;Perriard, Yves
    • Journal of international Conference on Electrical Machines and Systems
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    • v.3 no.3
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    • pp.325-330
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    • 2014
  • Eddy current induction is used in a wide range of electronic devices, for example in detection sensors. Due to the advances in computer hardware and software, the need for 3D computation and system comprehension is a requirement to develop and optimize such devices nowadays. Pure theoretical models are mostly limited to special cases. On the other hand, the classical use of commercial Finite Element (FE) electromagnetic 3D models is not computationally efficient and lacks modeling flexibility or robustness. The proposed approach focuses on: (1) implementing theoretical formulations in 3D (FE) model of a detection device as well as (2) an automatic Volumetric Estimation Method (VEM) developed to selectively model the target finite elements. Due to these two approaches, this model is suitable for parametric studies and optimization of the number, location, shape, and size of PCB receivers in order to get the desired target discrimination information preserving high accuracy with tenfold reduction in computation time compared to commercial FE software.

Aviation stability analysis with coupled system criterion of theoretical solutions

  • C.C. Hung;T. Nguyen
    • Coupled systems mechanics
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    • v.12 no.3
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    • pp.221-239
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    • 2023
  • In our research, we have proposed a solid solution for aviation analysis which can ensure the asymptotic stability of coupled nonlinear plants, according to the theoretical solutions and demonstrated method. Because this solution employed the scheme of specific novel theorem of control, the controllers are artificially combined by the parallel distribution computation to have a feasible solution given the random coupled systems with aviation stability analysis. Therefore, we empathize and manually derive the results which shows the utilized lemma and criterion are believed effective and efficient for aircraft structural analysis of composite and nonlinear scenarios. To be fair, the experiment by numerical computation and calculations were explained the perfectness of the methodology we provided in the research.

Inference of Parameters for Superposition with Goel-Okumoto model and Weibull model Using Gibbs Sampler

  • Heecheul Kim
    • Communications for Statistical Applications and Methods
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    • v.6 no.1
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    • pp.169-180
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    • 1999
  • A Markov Chain Monte Carlo method with development of computation is used to be the software system reliability probability model. For Bayesian estimator considering computational problem and theoretical justification we studies relation Markov Chain with Gibbs sampling. Special case of GOS with Superposition for Goel-Okumoto and Weibull models using Gibbs sampling and Metropolis algorithm considered. In this paper discuss Bayesian computation and model selection using posterior predictive likelihood criterion. We consider in this paper data using method by Cox-Lewis. A numerical example with a simulated data set is given.

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Characterization of Spherical Particles by Light Scattering

  • Sangwook Park;Jungmoon Sung;Taihyun Chang
    • Bulletin of the Korean Chemical Society
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    • v.12 no.3
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    • pp.322-328
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    • 1991
  • We have studied a characterization method of accurate size of spherical particles by fitting experimental light scattering profile to the rigorous theoretical scattering function. An efficient software has been developed for computation of the theoretical scattering function and regression analysis. A light scattering instrument has been built and the necessary data acquisition and analysis are carried out by use of a personal computer with an emphasis on the reduction of analysis and time aiming that this study will be extended toward a development of a practical particle sizing apparatus. The performance of the instrument and the software has been evaluated with latex spheres and found to be satisfactory.

Adaptive Moment-of-Fluid Method:a New Volume-Tracking Method for Multiphase Flow Computation

  • Ahn, Hyung-Taek;Shashkov, Mikhail
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03a
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    • pp.334-336
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    • 2008
  • A novel adaptive mesh refinement (AMR) strategy based on the Moment-of-Fluid (MOF) method for volume-tracking dynamic interface computation is presented. The Moment-of-Fluid method is a new interface reconstruction and volume advection method using volume fraction as well as material centroid. The mesh refinement is performed based on the error indicator, the deviation of the actual centroid obtained by interface reconstruction from the reference centroid given by moment advection process. Using the AMR-MOF method, the accuracy of volume-tracking computation with evolving interfaces is improved significantly compared to other published results.

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Adaptive Moment-of-Fluid Method: a New Volume-Tracking Method for Multiphase Flow Computation

  • Ahn, Hyung-Taek;Shashkov, Mikhail
    • 한국전산유체공학회:학술대회논문집
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    • 2008.10a
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    • pp.334-336
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    • 2008
  • A novel adaptive mesh refinement (AMR) strategy based on the Moment-of-Fluid (MOF) method for volume-tracking dynamic interface computation is presented. The Moment-of-Fluid method is a new interface reconstruction and volume advection method using volume fraction as well as material centroid. The mesh refinement is performed based on the error indicator, the deviation of the actual centroid obtained by interface reconstruction from the reference centroid given by moment advection process. Using the AMR-MOF method, the accuracy of volume-tracking computation with evolving interfaces is improved significantly compared to other published results.

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