• Journal of the Korean Society for Precision Engineering
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• v.22 no.3 s.168
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• pp.78-85
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• 2005

The static implicit finite element method is applied effectively to analyze total roof panel stamping processes, which include the forming stage. complicated and abnormal Large size roof panel was analyzed by using commercial program called AutoForm. Analysis results examining possibility and validity of the AutoForm software and the factor study are presented. Further, the simulated results for the total roof panel stamping processes are shown and discussed. Its application is being increased especially in the automotive industrial area for the cost reduction, weight saving, and improvement of strength.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.243-248
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• 2007

A three-dimensional (3D) unstructured hydrodynamic solver for transient two-phase flows has been developed. A two-fluid three-field model was adopted for the two-phase flows. The three fields represent a continuous liquid, an entrained liquid, and a vapour field. The hydrodynamic solver is for the 3D component of a nuclear system code and the component-scale analysis tools for transient two-phase flows. The finite volume method and unstructured grid are adopted, which are useful for the flows in a complicated geometry. The semi-implicit ICE (Implicit Continuous-fluid Eulerian) numerical scheme has been adapted to the unstructured non-staggered grid. This paper presents the numerical method and the preliminary results of the calculations. The results show that the numerical scheme is robust and predicts the phase change and the flow transitions due to boiling and flashing problems well.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.12
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• pp.2374-2391
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• 2011

A variety of reconstruction methods has been developed to convert a set of scattered points generated from real models into explicit forms, such as polygonal meshes, parametric or implicit surfaces. In this paper, we present a method to construct multi-scale implicit surfaces from scattered points using multiscale kernels based on kernel and multi-resolution analysis theories. Our approach differs from other methods in that multi-scale reconstruction can be done without additional manipulation on input data, calculated functions support level of detail representation, and it can be naturally expanded for n-dimensional data. The method also works well with point-sets that are noisy or not uniformly distributed. We show features and performances of the proposed method via experimental results for various data sets.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.75-78
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• 2005

The static implicit finite element method is applied effectively to analyze back inner panel stamping processes, which include the forming stage Analysis results examining possibility and validity of the formulation and the factor of study are presented. Further, the simulated results for f/apron panel stamping processes are shown and discussed. Its application is being increased especially in the automotive industrial area for the cost reduction, weight saving, and improvement of strength.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.4
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• pp.320-329
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• 2016

An implicit method of solving the six degree-of-freedom rigid body motion equations based on the second order Adams-Bashforth-Moulten method was utilised as an improvement over the leapfrog scheme by making modifications to the rigid body motion solver libraries directly. The implementation will depend on predictor-corrector steps still residing within the hybrid Pressure Implicit with Splitting of Operators - Semi-Implicit Method for Pressure Linked Equations (PIMPLE) outer corrector loops to ensure strong coupling between fluid and motion. Aitken's under-relaxation is also introduced in this study to optimise the convergence rate and stability of the coupled solver. The resulting coupled solver ran on a free floating object tutorial test case when converged matches the original solver. It further allows a varying 70%-80% reduction in simulation times compared using a fixed under-relaxation to achieve the required stability.

• Water for future
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• v.16 no.2
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• pp.123-129
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• 1983

One of the techniques to determine flood stages in natural channel is to find the solution of unsteady flow equations such as continuity and momentum equations. Since the exact analytic solution of these equations are not Known, the implicit numerical scheme is widely accepted tool for the approximate solution of equations. This technique is applied to the downstream of Daechung Dam in Geum River for the determination of flood stage for given frequency. However the flood stages are greatly affected by the method of reservoir Operation Method and Technical Operation Reservoir Method. Obviously, the Tech. ROM is found to be superior to Auto ROM.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.4
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• pp.315-322
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• 2009

This paper presents a novel numerical method based on the extended moving least squares finite difference method(MLS FDM) for solving 1-D Stefan problem. The MLS FDM is employed for easy numerical modelling of the moving boundary and Taylor polynomial is extended using wedge function for accurate capturing of interfacial singularity. Difference equations for the governing equations are constructed by implicit method which makes the numerical method stable. Numerical experiments prove that the extended MLS FDM show high accuracy and efficiency in solving semi-infinite melting, cylindrical solidification problems with moving interfacial boundary.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.5 s.51
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• pp.99-106
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• 2006

The Real-Time Hybrid Test system presented in this paper is based on the pseudodynamic test method, and it combines physical testing with model-based simulation. The system is designed to achieve a rate of loading that is significantly higher than that of a conventional pseudodynamic test approaching the real-time response of a structure subjected to earthquake loads. To provide robust computation environment for the analysis of many degree-of-freedom structures, the system adopts an implicit time integration scheme in the model-based simulation. This paper presents an overview of the developed system and numerical simulations that were conducted to evaluate the performance of the computation scheme adopted here. Results of these studies have demonstrated the good performance of the computation scheme for real-time multiple-degree-of-freedom tests.

• Journal of Digital Contents Society
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• v.8 no.1
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• pp.85-91
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• 2007

This paper proposes a new hybrid anti-aliasing method for reducing aliasing appearing on an implicit surface using the point sampling. The hybrid anti-aliasing method is a method that finds differences in the values of pixel shown in Z-buffers for an implicit surface and thereby uses each of three types of Z-buffer. After determining the level of differences, it expresses a 3 dimensional object by using a multi Z-buffer if the level is severe, a double Z-buffer for a middle level, and only the original Z-buffer for a negligible difference. In comparison with the existing method in which multi Z-buffers have been entirely used for enhancing the anti-aliasing effect, the hybrid anti-aliasing method is an efficient method demonstrating an effect similar to the one using a multi Z-buffer while reducing the number of Z-buffers to be used.

• Korean Journal of Cognitive Science
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• v.27 no.4
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• pp.599-618
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• 2016

The relationship between dependent personality traits and depression has been widely studied in the field of psychology. However, the existing evidence is mixed and often contradictory, obscuring the precise nature of this relationship. Given that the most common method of measuring the construct of dependency has been to administer self-report instruments, it is possible that implicit dependency, another parameter of dependency that is distinct from explicit dependency measured via self-report, is confounding these results. The current study aimed to clarify the relationship between dependency and depression by comparing the effect of implicit and explicit dependency. Implicit dependency was measured via the Single Category-Implicit Association Test (SC-IAT), a test of implicit personality that has shown to have good validity and reliability in previous studies. In addition, we examined the effect of gender on this relationship, given the potential role of gender stereotype that may make male participants show lower levels of dependency when measured through self-report (vs. SC-IAT). Results showed that implicit and explicit dependency indeed had separate and distinct relationships, and the relationships depends on participants' gender. Among female participants, increased explicit dependency predicted depression only when implicit dependency was also elevated. In contrast, explicit dependency predicted depression regardless of the level of implicit dependency in male participants. These findings suggest that implicit and explicit dependency may be separate parameters capturing different aspects of dependent personality traits, further supporting the need to consider the implicit aspect of personality in personality assessment research. Implications and limitations of the current findings and directions for future research are discussed.