• Journal of information and communication convergence engineering
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• v.9 no.5
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• pp.573-576
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• 2011

In this paper is given one method of constructing payment via commonly used mobile phone, SIM-card and plastic card based on USSD-commands.

• Journal of the Korea Safety Management & Science
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• v.2 no.2
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• pp.167-176
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• 2000

A study to analyze and solve problems of plastic injection molding experiment has presented in this paper. We have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.5
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• pp.487-499
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• 2009

The postprocessing technology has been advanced diversely to accommodate the tendency of increasingly refined and complicated practices of finite element modeling in pace with enhanced capabilities of computers and improved algorithm of equation solvers. As a result of such progresses in both hardware and software, it became practically meaningful to inspect and analyze the elasto-plastic behavior using the intermediate results from the increasing number of incremental and iterative processes. This paper is concerned about the new methods of postprocessing with computer graphic visualization of elasto-plastic behavior on the basis of the theoretically reorganized analysis results. This paper proposes a new method of rendering the plastic zone, and new approaches of analyzing and interpreting the elasto-plastic behavior using the graphical information visualized in the form of the yield surface and the stress path, or in the form of the Mohr circles and the failure envelope.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.48-52
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• 2008

Waste paper plastic composites were prepared with old newspaper and old corrugated containers and mixed office waste and those properties were evaluated. The results were summarized as fellows. 1. The strength properties like as tensile and Young's modulus reveled most high level in MOW composite. 2. The coagulation of fibers in paper particle should interrupt equal dispersion of polymer and paper particle. 3. The micrograph of the surface of composites showed the most high dispersion in ONP composite.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.331-340
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• 2000

For the rational and economic design of the structural elements of ships which is built using welding, the ultimate strength analyses of the plates having initial imperfections, such as welding residual stresses and strains, are needful. The welding deformation usually relied on approximative equations or based on expert's experience. But in this paper, for the thermal elasto-plastic analysis of plates, the finite element analysis was performed, based on initial strain method. In formulating the incremental analysis, unbalanced force terns were included. In the plastic domain during the incremental process, the 2nd order terns stress increment and yield stress increment were considered, so that time increment could be controlled for a more stable solution. The ultimate strength analysis program of the plates having initial imperfections was made. The ultimate strength analysis was carried out based on the results of the welding deformations of this paper. In the ultimate strength analysis the Rayleigh-Ritz method based on the minimum potential theory was used.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.347-350
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• 2004

In this paper, the acceleration is studied for the rigid-plastic FEM of metal forming simulation. In the FEM, the direct iteration and Newton-Raphson iteration are applied to obtain the initial solution and accurate solution respectively. In general, the acceleration scheme for the direct iteration is not used. In this paper, an Aitken accelerator is applied to the direct iteration. In the modified Newton-Raphson iteration, the step length or the deceleration coefficient is used for the fast and robust convergence. The step length can be determined by using the accelerator. The numerical experiments have been performed for the comparisons. The faster convergence is obtained with the acceleration in the direct and Newton-Raphson iterations.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.158-165
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• 2003

A specific experimental method, the Split Hopkinson pressure bar (SHPB) technique has been widely used to determine the dynamic material properties under the impact compressive loading conditions with strain rate of the order of 10$^3$/s∼l0$^4$/s. In this paper, dynamic deformation behaviors of rubber materials widely used for the isolation of vibration from structure under varying dynamic loading are determined by using plastic SHPB technique. A transition point to scope with the dynamic deformation behavior of rubber-like material is defined in this paper and used to characterize the specifics of the dynamic deformation of rubber materials.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.785-788
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• 2005

In this paper, the influence of many factors related to the concrete mixture and the weather condition on plastic shrinkage cracking are analyzed through parametric studies using the numerical models introduced in the companion paper. First of all, through a systematic calculation of bleeding, the relationship between the bleeding constants and concrete mixture is proposed on the basis of the experimental data obtained by many researchers. Moreover, an equation, which can directly determine a critical point at which the evaporation and bleeding is balanced, is introduced, and the efficiency of the introduced equation is verified through the correlation study between the obtained results by the introduced equation and those by the rigorous analyses. The introduced equation can effectively be used to predict and to prevent plastic shrinkage cracking without any rigorous analysis and, in advance, to cope with the sudden changes in the concrete mixture and/or weather condition.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4146-4158
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• 2023

This paper proposes a combined plastic and creep constitutive model of A533B1 pressure vessel steel to simulate progressive deformation of nuclear pressure vessels under severe accident conditions. To develop the model, recent tensile test data covering a wide range of temperatures (from RT to 1,100 ℃) and strain rates (from 0.001%/s to 1.0%/s) was used. Comparison with experimental data confirms that the proposed combined plastic and creep model can well reflect effects of temperature and strain rate on tensile behaviour up to failure. In the companion paper (Part II), the proposed model will be used to simulate OECD lower head failure (OLHF) test data.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.6
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• pp.133-139
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• 2008

In this paper, the feasibility for producing a plastic optical fiber sensor to be used as an anti-drowsy driving sensor is discussed. This sensor consists of a plastic optical fiber wound on the steering wheel covered by soft material. When a driver hold a steering wheel, the gripping force is induced and causes to the bend of the plastic optical fiber which decreases the power of light propagated inside the plastic fiber. The experimental results show that the detected optical power decrease as the gripping force increase and that this sensor can be used as the anti-drowsy driving sensor.