• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.77-80
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• 2001

The element-free Galerkin (EFG) method is one of meshless methods, which is an efficient method of modeling problems of fluid or solid mechanics with complex boundary shapes and large changes in boundary conditions. This paper discusses the theory of the EFG method and its applications to modeling of groundwater flow. In the EFG method, shape functions are constructed based on the moving least square (MLS) approximation, which requires only set of nodes. The EFG method can eliminate time-consuming mesh generation procedure with irregular shaped boundaries because it does not require any elements. The coupled EFG-FEM technique was introduced to treat Dirichlet boundary conditions. A computer code EFGG was developed and tested for the problems of steady-state and transient groundwater flow in homogeneous or heterogeneous aquifers. The accuracy of solutions by the EFG method was similar to that by the FEM. The EFG method has the advantages in convenient node generation and flexible boundary condition implementation.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.179.6-179
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• 2001

This paper proposes the recognition method of the strip shape using the Least-Square method and the distinction method of the asymmetric shape and the compensation method upon the shape control values for the stainless steel cold rolling mill. This paper proposes the shape recognition method before control and the compensation method to minimize the fluctuation of the shape deviation and to get symmetric shape. This paper shows on line test results to verify the performance of the control method for the process. The experiments have been performed with respect to various material type, thickness, and strip width. The performance of the proposed method is obtained excellent quality and high productivity as results.

• International Journal of Highway Engineering
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• v.18 no.4
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• pp.63-68
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• 2016

PURPOSES : The nonlinear model of fatigue cracking is typically used for determining the maintenance period. However, this requires that the model parameters be known. In this study, the particle filter (PF) method was used to determine various statistical parameters such as the mean and standard deviation values for the nonlinear model of fatigue cracking. METHODS : The PF method was used to determine various statistical parameters for the nonlinear model of fatigue cracking, such as the mean and standard deviation. RESULTS : On comparing the values obtained using the PF method and the least square (LS) method, it was found that PF method was suitable for determining the statistical parameters to be used in the nonlinear model of fatigue cracking. CONCLUSIONS : The values obtained using the PF method were as accurate as those obtained using the LS method. Furthermore, reliability design can be applied because the statistical parameters of mean and standard deviation can be obtained through the PF method.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.25-31
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• 2002

A system identification method is introduced to increase the prediction accuracy of a ship's maneuverability in PMM test, analysis. To improve the accuracy of linear hydrodynamic coefficients, the analysis techniques of pure sway and yaw tests are developed, and confirmed. In the analysis of sway tests, accuracy to linear hydrodynamic coefficients depends on the frequency of sway motion. To obtain nonlinear hydrodynamic coefficients for large drift angles, a combined yaw test is introduced. Using this system identification method, runs of PMM test can be reduced while retaining sufficient accuracy, compared to the Fourier integration method. Through the comparisons with sea trial results and the Fourier integration method, the accuracy and efficiency of the newly proposed system identification method, based on least square method, has been validated.

• Structural Engineering and Mechanics
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• v.57 no.2
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• pp.281-294
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• 2016

The paper is devoted to study a mesh-free analysis method of structural elements of engineering structures based on B-spline Wavelet Basis Function. First, by employing the moving-least square method and the weighted residual method to solve the structural displacement field, the control equations and the stiffness equations are obtained. And then constructs the displacement field of the structure by using the m-order B-spline wavelet basis function as a weight function. In the end, the paper selects the plane beam structure and the structure with opening hole to carry out numerical analysis of deformation and stress. The Finite Element Method calculation results are compared with the results of the method proposed, and the calculation results of the relative error norm is compared with Gauss weight function as weight function. Therefore, the clarification verified the validity and accuracy of the proposed method.

• Journal of Science of Art and Design
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• v.1
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• pp.63-93
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• 1999

This treatise begins with finding a meaning of Paul Klee's . It is pretty simpleto choose the square of Klee. The most important formative language for twenty century is abstraction. The element of speaking for abstraction issquare. The artists are trying to contain the nature and universe in the square. The role of magic square consisting with small squares of Klee is crystallized. The other side, the test of this study is a method analysis. The method analysis is changing while concept and style have been changing according to a period. The existing method analysis is an iconology used many times in Art history. This treatise introduces France symbolists, Bernard Cocula and Claude Peyroutet's analysis of a meaning of image(Semantique do l'image) who were applied to Modern Art. based on Iconography. It also applies to analysis of artwork of Klee. Cocula's is developed from one phase to five phase step by step. The first phase deals with an appearance of artwork. Subsequently, the second phase is directly adjacent to personal feeling and impression. This is an adequate method for image study in the analysis of modern arts. This phase makes it a rule to enjoy talking with artworks above all. The third phase begins with this question 'What do you see? (que voyons-nous?).' The applies exhaustively and strictly to complicated image artworks which need an elaborate analysis. It is very hard but audiences must try to maintain neutrality in front of artwork because cord formation and interpretation should be formed objectively. The meaning analysis and interpretation of the forth phase begins with this question 'what is the image rouse'(qu'evoque cote image?).' This phase is the most important in a process of symbolic analysis. The audience investigates personal elements and common elements. The fifth is synthetic analysis and interpretation phase. The synthesis is last phase and it reaches a valuation and a conclusion. Namely, the synthesis phase makes up synthesis conclusion, summarizes image character, and completes value adjudication. Sometimes it completes no conclusions in a silence. This study found a new possible analysis example from Paul Klee's work. The study emphasizes square analysis and interpretation and uses . The analysis of artwork by Cocula's is an example of the most important work of Klee's three artworks. The first analysis of artwork is and the second one is . The third one is . In these analyses, Klee usedmagic square 'to make natural pictorial element and to explain organic living things.'

• 한국전산유체공학회:학술대회논문집
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• 2007.04a
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• pp.17-22
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• 2007

Chimera grid Method is widely used in Computational Fluid Dynamics due to its simplicity in constructing grid system over complex bodies. Especially, Chimera grid method is suitable for unsteady flow computations with bodies in relative motions. However, interpolation procedure for ensuring continuity of solution over overlapped region fails when so-call orphan cells are present. We have adopted MLS(Moving Least Squares) method to replace commonly used linear interpolations in order to alleviate the difficulty associated with orphan cells. MSL is one of interpolation methods used in mesh-less methods. A number of examples with MLS are presented to show the validity and the accuracy of the method.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.209-215
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• 2012

This paper deals with the construction of system for correct location determination of fixed tag. We adapted to construct the above method. Also we adapted the several filtering method. This system was constructed through using of several filtering methods to decrease the location determination error and fingerprint method which is composed of training phase and positioning phase. We constructed this system using Labview 2010 and MS-SQL 2000 as database. This system results in less location determination error than least square method, triangulation positioning method, and other fingerprint methods.

• Journal of Biomedical Engineering Research
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• v.37 no.1
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• pp.21-30
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• 2016

Weibull distribution with two parameters, shape (k) and scale (s) parameters are used to model the fatigue failure analysis due to periodic vortex shedding of the synovial fluid in knee joints. In order to determine the later parameter, a suitable statistical model is required for velocity distribution of synovial fluid flow. Hence, wide applicability of Weibull distribution in life testing and reliability analysis can be applied to describe the probability distribution of synovial fluid flow velocity. In this work, comparisons of three most widely used methods for estimating Weibull parameters are carried out; i.e. the least square estimation method (LSEM), maximum likelihood estimator (MLE) and the method of moment (MOM), to study fatigue failure of bone joint due to periodic vortex shedding of synovial fluid. The performances of these methods are compared through the analysis of computer generated synovial fluidflow velocity distribution in the physiological range. Significant values for the (k) and (s) parameters are obtained by comparing these methods. The criterions such as root mean square error (RMSE), coefficient of determination ($R^2$), maximum error between the cumulative distribution functions (CDFs) or Kolmogorov-Smirnov (K-S) and the chi square tests are used for the comparison of the suitability of these methods. The results show that maximum likelihood method performs well for most of the cases studied and hence recommended.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1392-1395
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• 1996

Nonlinear PID controllers have increasingly used in current industrial practice because it is robust and is easy to operate. Little guideline and tuning method, however, has been recommended for the nonlinear PID controllers while a lot of result is available for the linear PID controllers. Application guideline and tuning formulae are presented for error square type nonlinear controllers, which are most popular currently, are presented.