• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.10a
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• pp.38-45
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• 1994

P-version finite element model for the computation of stress intensity factors in two dimensional cracked panels by J-integral method is presented. The proposed model is based on high order theory and hierarchical shape function. The displacements fields are defined by integrals of Legendre polynomials which can be classified into three part such as basic mode, side mode, integral mode. The stress intensity factors are computed by J-integral method. The example models for validating the proposed p-version model are centrally cracked panel, single and double edged crack in a rectangular panel under pure Mode I. And the analysis results are compared with those by the h-version of FEM and empirical solutions in literatures. Very good agreement with the existing solution are shown.

• Journal of the Korea Computer Industry Society
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• v.2 no.8
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• pp.1099-1108
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• 2001

In this paper, we proposed an efficient method of management in which various design objects in the environments for distributed software development. Those design objects are created in the environments for distributed software development based on Unified Modeling Language as well as versions of source codes. In this research, a version control technique has been specially focused that is based on our proposed version rules to consistently control versions from web-based distributed software development which enables developers to independently manage distributed objects from the software development platform. Based on the version control technique, we have designed a web-based rule-control version management model that has been proposed here.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.7
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• pp.966-973
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• 1995

In this paper, we compare several methods for implementing a VHDL design database through a case study on VHDL tool development system. We implemented three versions of the VHDL design database which the VHDL tool development system is based on. The first version was coded in the C programming language following value-oriented paradigm. The second one was coded in the C++ programming language following object-oriented paradigm. The third one was implemented using an existing object-oriented database. Based on our experience, we present quantitatively the pros and cons of each implementation method. The value-oriented version was most difficult to implement but showed good performance. Compared to the value- oriented version, the C++ version was twice as easy to implement and showed about the same performance. Using an existing object-oriented database allowed easiest implementation but resulted in a 1.5 to 6 times slower version.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.69-76
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• 1998

Due to the drastic improvement of computer hardware and operating system, it is easy to break through the main defects of limited computer memory and processing time, etc. To keep up with this situation, this paper is focused on developing the preprocessor program with the input method based on vector graphic editor and the preprocessing technique including automatic node generation algorithm for the $\rho$-version finite element program. To develop this preprocessor program, the special data structure and the OOP(Object Oriented Programming) have been used by the Visual Basic 4.0. The Special data structure is proposed to describe the geometric data of node numberings and coordinates suitable for the $\rho$-version finite element program, which are quite different from the comvential h-version finite element program.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.33-40
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• 1998

Although a structural analysis based on e linear elastic theory yields good results for deformations and stresses produced by working loads, it fails to assess the teal load-carrying of the plates on the verge of yielding. In case of a limit analysis of plates, the yield line theory is widely used on the basis of the upper bound theorem and theoretically it overestimates the strength of the plate. There is, therefore, a general need for analytical methods of predicting the inelastic behavior and load-carrying capacities of plate subjected to arbitrary loadings and boundary conditions. The $\rho$-version of finite element method has been presented for determining the accurate limit load of plates. The numerical results by $\rho$-version model compares with the results obtained by the h-version software ADINA as well as with the available analytical solutions in literatures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.145-152
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• 1995

A general stiffener element which includes transverse shear deformation(TSD) is formulated using the p-version of finite element method. Hierarchic C"-shape functions, derived from Integrals of Legendre polynomials, are used to define the assembled stiffness matrix of the stiffener and plate on the basis of 5 D.0.F displacement fields. The stiffness matrix for the stiffener with respect to the local reference frame is transformed to the plate reference system by applying the appropriate transformation matrices in order to insure compatibility of displacements at the junction of the stiffener and plate. The transformation matrices which account for the orientation and the eccentricity effects of the stiffener with respect to the plate reference axes are used to find local behavior at the junction of the stiffener and the relative contributions of the plate and stiffener to the strength of the composite system. The results obtained by the p-version of the finite element method are compared with the results in literatures, especially those by the h-version software, MICROFEAP-II.P-II.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.429-436
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• 1999

The best available solution to predict the fatigue life of structural steels is the implementation of EPFM approach based on the principles and techniques of elasto plastic fracture mechanics. To predict the fatigue life, the conventional Paris law has been modified by substituting the range of J-value denoted by ΔJ for ΔK that is calculated by the proposed p-version model. The proposed P-version finite element model is formulated by the incremental theory of Plasticity that consists of the constitutive equation fur elastic-perfectly plastic materials, Tresca/von-Mises yield criteria, and associated flow rule. The experimental fatigue test is conducted with five UP(Center Clucked Panels) specimens to validate the accuracy of the p-version finite element model. Also, the results obtained by LTM approach have been compared with those by EPFM approach.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.04a
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• pp.71-78
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• 1997

The high precision analysis by the p-version of the finite element method are fairly well established as highly efficient method for linear elastic problems, especially in the presence of stress singularity. It has been noted that the merits of p-version are accuracy, modeling simplicity, robustness, and savings in user's and CPU time. However, little has been done to exploit their benefits in elasto-plastic analysis. In this paper, the p-version finite element model is proposed for the materially nonlinear analysis that is based on the incremental theory of plasticity, the associated flow rule, and von-Mises yield criteria. To obtain the solution of nonlinear equation, the Newton-Raphson method and initial stiffness method, etc are used. Several numerical examples are tested with the help of the square plates with cutout, the thick-walled cylinder under internal pressure, and the center cracked plate under tensile loading. Those results are compared with the there cal solutions and the numerical solutions of ADINA software.

• Journal of Korea Multimedia Society
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• v.11 no.12
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• pp.1749-1757
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• 2008

This research proposes a modified version of single pass algorithm specialized for text clustering. Encoding documents into numerical vectors for using the traditional version of single pass algorithm causes the two main problems: huge dimensionality and sparse distribution. Therefore, in order to address the two problems, this research modifies the single pass algorithm into its version where documents are encoded into not numerical vectors but other forms. In the proposed version, documents are mapped into tables and the operation on two tables is defined for using the single pass algorithm. The goal of this research is to improve the performance of single pass algorithm for text clustering by modifying it into the specialized version.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.8 no.3
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• pp.231-237
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• 2008

This research proposes a modified version of single pass algorithm specialized for text clustering. Encoding documents into numerical vectors for using the traditional version of single pass algorithm causes the two main problems: huge dimensionality and sparse distribution. Therefore, in order to address the two problems, this research modifies the single pass algorithm into its version where documents are encoded into not numerical vectors but other forms. In the proposed version, documents are mapped into tables and the operation on two tables is defined for using the single pass algorithm. The goal of this research is to improve the performance of single pass algorithm for text clustering by modifying it into the specialized version.