• Geomechanics and Engineering
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• v.29 no.6
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• pp.683-696
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• 2022

Dams are inevitably planned to be built on thick overburden with high permeability and deformability. The connection part between concrete cut-off wall in overburden and earth core in dam body is not only a key part of the anti-seepage system, but also a weak position. Large uneven settlement will be aroused at the concoction part. However, the interaction behavior and the scope of the connection part cannot be determined effectively. In this paper, numerical analysis of a high earth core dam built on thick overburden was carried out with large deformation FE method. The mechanical behavior of the connection part was detail studied. It can be drawn that there is little differences in dam integral deformation for different analysis method, but big differences were found at the connection part. The large deformation analysis method can reasonably describe the process that concrete wall penetrates into soil. The high plasticity clay has stronger ability to adapt to large uneven deformation which can reduce stress level, and stress state of concrete wall is also improved. The scope of high plasticity clay zone in the connection part can be determined according to stress level of soils and penetration depth of concrete wall.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1299-1307
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• 2006

This study investigates solving production problems in an automotive stamping plant using Finite Element (FE) analysis. The fundamentals of stamping, metal plasticity and FE analysis are developed. In this paper, we provide the basis for a simulation of the stamping of a production part, the automotive rear floorpan. On-plant factorial Design of Experiments (DoE) were simulated using the floorpan model. The accuracy of the simulations was undetermined because of variability in the DoE results. Predictions of flange shape, wrinkling and thickness show qualitative agreement with manufactured parts and indicate that simulating an industrial part is feasible.

• Structural Engineering and Mechanics
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• v.47 no.2
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• pp.209-225
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• 2013

A procedure employing a Teaching-Learning Based Optimization (TLBO) method is developed to design discrete pin jointed structures. TLBO process consists of two parts: the first part represents learning from teacher and the second part illustrates learning by interaction among the learners. The results are compared with those obtained using other various evolutionary optimization methods considering the best solution, average solution, and computational effort. Consequently, the TLBO algorithm works effectively and demonstrates remarkable performance for the optimization of engineering design applications.

• Steel and Composite Structures
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• v.4 no.2
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• pp.133-147
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• 2004

This paper deals with the asymptotic analysis of Mohr-Coulomb and Drucker-Prager soft thin layers bonded with elastic solids. In the first part, a mathematical analysis shows how to obtain an interface law that replaces mechanically and geometrically the thin layer. This law is strongly non-linear and couples microscopic and macroscopic scales. In the second part of the paper, the microscopic terms are quantified numerically, and it is shown that they can be neglected.

• Wind and Structures
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• v.15 no.4
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• pp.301-311
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• 2012

This paper presents results from the structural monitoring of a steel wind tower characterized and presented in Part I of the paper. Monitoring period corresponds to about fifteen months of measurements. Results presented refer to stress distribution on shell and in bolts at different heights, stress fatigue spectra, section forces along height evaluated from the stress measurements and comparison with design forces, dynamic response in terms of accelerations, stresses, deflections and rotations.

• Structural Engineering and Mechanics
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• v.40 no.5
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• pp.617-636
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• 2011

We present the numerical implementation, simulation, and validation of the high-velocity impact experiments that have been described in the companion article. In this part, numerical investigations and simulations performed to mimic the tests are presented. The experiments were analyzed by the explicit integration-based software ABAQUS for improved simulations. Targets were modeled with a damaged plasticity model for concrete. Computational results of residual velocity and crater dimensions yielded acceptable results.

• Transactions of Materials Processing
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• v.17 no.4
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• pp.263-271
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• 2008

Process design is carried out for a press forming of a CTBA in the rear suspension assembly based on the result of the finite element analysis. The analysis simulates the two-stage stamping process with the initial design and it fully reveals the unfavorable mechanism which develops inferiorities during forming. In this paper, a new design guideline is proposed to modify the process and tool shapes for a single-stage forming process. With the improved tool design, prototypes are fabricated after several try-out processes. Results of the durability tests show that the design requirement of the part is satisfied and the effective weight reduction is achieved.

• 연구논문집
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• s.22
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• pp.65-74
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• 1992

This paper aims at calculating optimum design dimensions to minimize the weight satisfied strain and stress intensity of the frame while loading maximum weight into a mechanical press in the static condition. Analysis of the frame was carried out by using the FEM, then the optimum condition was obtained by using these data. As modeling in the finite element analysis has great impact on the reliablity of analysis results, the analyzed object was selected a 150-ton mechanical press of J Company, the part little affected to structural rigidity was simplified, the load condition was considered in the only maximum load, the boundary condition was used by giving symmetric displacement due to symmetric boundary condition, the finite element was applied a linear membrane element. An intermediate processor program applied the normal ANSYS to analyze finite elements was developed, and the design sensitivity was calculated. This program was applied to the optimum design.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.493-496
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• 2008

The residual stress generated in the boron steel blank formed via hot press forming process was predicted by JMatPro, a material property modeler, and Abaqus. The numerical predictions were compared by the experimental measurements obtained by the instrumented indentation. Both the predicted and measured principal stresses monitored at the outer surface of central bending position were qualitatively in good agreement. It was concluded that the residual stresses generated from hot forming process is not negligible as it has been generally assumed, although the spring back deformation is quite small. This should be specially considered from the part design stage since the tensile nature of the residual stress exhibited on the surface may lead to the stress corrosion cracking.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.3
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• pp.105-111
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• 2003

This paper presents an approach to automate process planning of press dies for manufacturing of car bodies. Considering that the press-dies used at the same press operations regardless of the panels they produce or the car models of which they produce panels have similar shapes except for the forming part of the dies, general approaches to recognize manufacturing features from CAD models are not necessary. Therefore, a hybrid approach is proposed combining feature-based design and feature-extraction approaches. The proposed method recognizes features by parsing the parameters extracted from CAD models and finds proper operations by querying the database by the recognized features. An internet-based process planning system is developed to demonstrate the proposed approach and to suggest a new paradigm of process planning system that utilizes an internet access to the CAD system.