• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1992.10a
• /
• pp.112-120
• /
• 1992

The use of Pre-processor for building structural analysis used to rely upon filling up fixed format data, which was ineffective and error-prone. This research attempts to integrate structural analysis system with DBMS and CAD system in order to make it easy to exchange data between pre-process, analysis, and post-process stages. Automatic generation of database from pre-process stage allows easy preparation of main input data for other structural analysis programs. CAD system with some sub-programs written in LISP and C works as a graphic user interface. This approach gives an easy, effective and error-free way of inputing data for structural analysis.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.14 no.1
• /
• pp.26-33
• /
• 2001

The proposed system was composed of pre-processor which was executing binary/high-pass filtering and post-processor which ranged from statistic data to prediction. In post-processor work, step one was filter process of image, step two was image recognition, and step three was destruction degree/time prediction. After these processing, we could predict image of the last destruction timestamp. This research was produced variation value according to growth of tree pattern. This result showed improved correction, when this research was applied image Processing. Pre-processing step of original image had good result binary work after high pas- filter execution. In the case of using partial discharge of the image, our research could predict the last destruction timestamp. By means of experimental data, this prediction system was acquired $\pm$3.2% error range.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.07a
• /
• pp.319-322
• /
• 2001

The proposed system was composed of pre-processor which was executing binary/high-pass filtering and post-processor which ranged from statistic data to prediction. In post-processor work, step one was filter process of image, step two was image recognition, and step three was destruction degree/time prediction. After these processing, we could predict image of the last destruction timestamp. This research was produced variation value according to growth of tree pattern. This result showed improved correction, when this research was applied image Processing. Pre-processing step of original image had good result binary work after high pass- filter execution. In the case of using partial discharge of the image, our research could predict the last destruction timestamp. By means of experimental data, this Prediction system was acquired ${\pm}$3.2% error range.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.10
• /
• pp.6673-6678
• /
• 2015

Recently, the free form buildings are constructed frequently. Exterior and interior components of these buildings have the free cross-section and a curved shape. So, There are many usages of classical finite element having tapered section and free-style shape. Some general commercial applications like ETABS, SAP2000, MIDAS are usually used for the safety evaluation of the free form structures. However, there are some limits in the accuracy of structural analysis and the length of analysis time because a very complicated finite element mesh have to be used. Therefore, In this study, a pre and post program module was developed to take advantage of general 3-D curved beam element which has a free-style curved shape and mathematical backgrounds. Pre-post processing module has been developed in this study was developed to control the curvature of the curved members by the NURBS control points. As a result, fast geometric modeling than was possible commercial applications. In addition, realistic depiction of the shape and behavior patterns were possible because of the free-form building allows visual check of the free form.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1996.04a
• /
• pp.270-274
• /
• 1996

Until recently pre & post-processing of finite element model has been heavily relied on expensive graphic peripheral devices. But today, with the aid of inexpensive microcomputers, very effective pre & postprocessor graphics has been developed. In this study, Pre & Post processor(MASSPRE, MASSPOST) of prediction analysis of thermal stress in mass concrete structure is developed. The developed pre & post processors are raise to the efficiency in making input data for the main program and analysis of the results produced by the main program. This MASSPOST presents a stress contour graph, volume slice, time-temperature history graph, time-stress history graph, etc.

• Computational Structural Engineering
• /
• v.22 no.5
• /
• pp.44-51
• /
• 2009

• Journal of Korea Foundry Society
• /
• v.11 no.1
• /
• pp.54-62
• /
• 1991

A computer program which consists of pre-processor, main solidification simulator and post-processor has been developed for three dimensional solidification analysis of steel castings. The pre-processor is used for mesh generation in a small personal computing system. The modified finite difference method is adopted for the main solidification simulation algorithm. The post -processor graphically presents the simulation results and shows the formation of shrinkage defects. Several experiments on large steel castings in sand mold were carried out. The temperature variations in casting and mold with time are measured experimentally, and the results are compared with calculation results. Several numerical examples for the prediction of shrinkage cavity in large steel casting of SC42 and SCNCrM2 alloys are compared with experimental results. The effect of sleeve and chills on solidification patterns are also studied. Formation of shrinkage defects for the three cases of experimental castings are relatively well predicted by present model.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.2410-2413
• /
• 2005

Finite element method (FEM) has been widely used as a useful numerical method that can analyze complex engineering problems in electro-magnetics, mechanics, and others. CEMTool, which is similar to MATLAB, is a command style design and analyzing package for scientific and technological algorithm and a matrix based computation language. In this paper, we present new 3D FEM package in CEMTool environment. In contrast to the existing CEMTool 2D FEM package and MATLAB PDE (Partial Differential Equation) Toolbox, our proposed 3D FEM package can deal with complex 3D models, not a cross-section of 3D models. In the pre-processor of 3D FEM package, a new 3D mesh generating algorithm can make information on 3D Delaunay tetrahedral mesh elements for analyses of 3D FEM problems. The solver of the 3D FEM package offers three methods for solving the linear algebraic matrix equation, i.e., Gauss-Jordan elimination solver, Band solver, and Skyline solver. The post-processor visualizes the results for 3D FEM problems such as the deformed position and the stress. Consequently, with our new 3D FEM toolbox, we can analyze more diverse engineering problems which the existing CEMTool 2D FEM package or MATLAB PDE Toolbox can not solve.

• Journal of Korea Foundry Society
• /
• v.13 no.3
• /
• pp.268-275
• /
• 1993

In gravity die casting, die cooling systems are frequently employed with water cooling to remove the heat of the solidifying metal. Thermal modeling is an important technique in mold design for improving the productivity of the process. Computer simulation system which consists of pre-processor, main solidification simulator and post-processor has been developed for three dimensional solidification analysis of cyclic gravity die casting. The pre-processor is used for mesh generation in a PC system. The modified finite difference method is adopted for the main solidification simulation algorithm during all the casting cycles. The post-processor graphically presents the simulation results. Several experiments in automotive cast piston were carried out. The temperature variations in casting and mold with time are measured experimentally, and the results are compared with calculation results. The effects of cycle number on solidification pattern are also studied. Several experimental results for the prediction of shrinkage defects are compared with calculated results.

• 한국전산유체공학회:학술대회논문집
• /
• 1998.11a
• /
• pp.29-35
• /
• 1998

In this paper, the on-going effort and progress for developing an integrated software for automated CFD application is described. As an outcome of the effort devoted so far, a new system, ICFDIT, is developed and introduced in this paper. The new system can be used to solve fluid dynamics problems in a convenient graphical environment, and it includes a pre-processor, a main-processor, and a post-processor. Usage of the system and examples are demonstrated, and some issues for improvement of the system are discussed.