• Transactions of Materials Processing
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• v.12 no.4
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• pp.302-307
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• 2003

Hot rolled strip is cooled by air and water in Run-Out-Table. In this process, phase transformation and shape deformation occurs due to temperature drop. Because of un-ideal cooling condition of ROT, irregular shape deformation and phase transformation arise in the strip. which affect the strip property and lead to the residual stress of strip. And these exert effects on the following processes, coiling process, coil cooling process, and re-coiling process. Through these processes, the residual stress becomes higher and severe. For the prediction of residual stress distribution and shape deformation of final product, Finite element(FE) based model was used. It consists of non-steady state heat transfer analysis, elasto-plastic analysis. thermodynamic analysis and phase transformation kinetics. Successive FEM simulation were applied from ROT process to coil cooling process. In each process simulation, previous process simulation results were used for the next process simulation. The simulation results were matched well with the experimental results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.4
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• pp.14-21
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• 2012

This paper study a method of modeling and simulation of LED driver circuit for a design optimization. Simplified LED modeling is introduced and a driver IC, HV9910, is modeled by implementing the major function blocks. Circuit of buck type converter is constructed for simulation. Simulation includes not only the internal function of IC but also the various performance results such as LED array current control and dimming. Experiment results are also shown to prove the verification of its usage. This results show that the simulation approach is valid for a circuit optimization and a reduction of development time.

• Computers and Concrete
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• v.24 no.6
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• pp.571-578
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• 2019

This study aimed to investigate the permeable nature of pervious concretes (PC) through the moving particle simulation (MPS) method. In the simulation, the complex structure of a pervious concrete was virtually demonstrated as a lattice model (LM) of spherical beads, where the test of permeability was conducted. Results of the simulation were compared with the experimental ones for validation. As a result, MPS results showed the permeability index of the LM as almost twice as big as the actual PCs. A proposed virtual model was created to prevent the stuck of water flow in the MPS simulation of PC or LM. Successful simulation results were demonstrated with the model.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.21-29
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• 2013

PURPOSES: Simulation of aggregate slump test using equivalent sphere particle in DEM and its validity evaluation against lab aggregate slump test METHODS : In this research, aggregate slump tests are performed and compared with DEM simulation. To utilize spheric particles in YADE, equivalent sphere diameter concept is applied. As verification measures, the volume in slump cone filled with aggregate is used and it is compared with volume in slump cone filled with equivalent sphere particle. Slump height and diameter are also used to evaluate the suggested numerical method with equivalent concept RESULTS : Simulation test results show good agrement with lab test results in terms of loose packing volume, height and diameter of slumped particle clump. CONCLUSIONS : It is concluded that numerical simulation using DEM is applicable to evaluate the effect of aggregate morphological property in loose packing and optimum gradation determination based on the aggregate slump test simulation result.

• Journal of the Korea Society for Simulation
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• v.11 no.4
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• pp.25-32
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• 2002

Hydraulic systems of injection molding machine are modelled and simulated with AMESim which is a commercial program. Detail models of hydraulic components are simulated and simulation results are evaluated with maker's test results in catalog. Sub system models which is divided according to functional operation are made and its analysis results shows how design parameters work on operational characteristics like cylinder speed, cylinder displacement, pressure, flow rates at each node and so on. Total circuit model is also made and analyzed. The prediction made by simulation will be used design of hydraulic systems of injection molding machine.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.361-366
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• 2007

As the application of quantitative risk assessment (QRA) to food safety becomes widespread, it is now being questioned whether experimental results and simulated results coincide. Therefore, this paper comparatively analyzed experimental data and simulated data of the cross contamination, which needs summation of the simplest calculations in QRA, of chicken by Monte Carlo simulation and fuzzy math computation. In order to verify summation, the following basic operation was performed. For the experiment, thigh, breast, and a mixture of both parts were preserved for 24 hr at $20^{\circ}C$, and then the cell number of Salmonella spp. was measured. In order to examine the differences between experimental results and simulated results, we applied the descriptive statistics. The result was that mean value by fuzzy math computation was more similar to the experimental than that by Monte Carlo simulation, whereas other statistical descriptors by Monte Carlo simulation were more similar.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.877-888
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• 2021

The water entry behaviors of projectiles with different cone-headed angles were studied numerically, experimentally and theoretically, mainly focusing on the hydrodynamic impact in the initial stage. Based on MMALE algorithm, it was proposed a formula of impact deceleration, which relied on the initial entry velocity and cone-headed angle. Meanwhile, in order to verify the validity of the simulation model, experiments using accelerometer and high-speed camera were carried out, and their results were in a good agreement with simulation results. Also, theoretical calculation results of cavity diameter were compared with experiments and simulation results. It was observed that the simulation method had a good reliability, which would make forecast on impact deceleration in an engineering project.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.1
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• pp.9-15
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• 2009

There are various types of energy simulation tool to predict both thermal load and energy use. However, the problem about these software is that they have too much input variables and need expert with skills to run the simulation. Therefore, the purpose of this study is to develop the thermal analysis simulation program with input variables which eliminates coordinates of building components instead of using full coordinates by using DOE2. Since the simulation engine of the program is DOE2, the validity of S-DOE is performed by comparing peak heating and cooling load results with VisualDOE and annual energy use results with actual energy use of 1996. The results have shown that there are little difference between VisualDOE and S-DOE. Also it showed that there are little difference between actual energy use and S-DOE energy use results. S-DOE took less time to model a building than VisualDOE. These results reveals that the application of S-DOE have potentials in accurately predicting both energy load and energy use of the building and still have an advantage of taking less time to model a building.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.6
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• pp.769-778
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• 2016

Technical approach on the modeling, simulation and experimentation methods, which are applied for developing a constructive simulation and engagement experimentation software for supporting light weight torpedo operational tactics study, is introduced. Conceptual modeling for the weapon engagement and simulation entities, mathematical models for the simulation elements, approach for the design of experimentations are described, and screen shots of the software are also presented as some example results of experimentation and analysis. It is found that the simulation and experimentation results are useful to support and fulfill the mission needs and requests. As a consequence, the technical approach is rated to be appropriate to accomplish the dedicated purpose of the simulation and experiments.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.4
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• pp.73-84
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• 1994

Output analysis is one of the most important fields of simulation to achieve the accurate simulation results. This study shows how to analyze simulation output data in the steady state using Procrustes analysis technique which has not been used in the field of simulation yet. In this paper Procrustes analysis method is used to perform the analysis of simulation output efficiently and effectively by applying the improved version of the method. The experiments are conducted using M/M/1 queueing simulation model. The results obtained by Procrustes analysis method show better estimates for average waiting times and average queue lengths which are closer to true values and narrower confidence intervals than when replication-deletion method is used. Also it requires the smaller number of simulation runs.