• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1139-1143
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• 2003

HILS(Hardware-In-the-Loop Simulation) is a scheme that incorporates hardware components of primary concern in the numerical simulation environment. Due to its advantages over actual vehicle test and pure simulation, HILS is being widely accepted in automotive industries as test benches for vehicle control units. Developed in this study is a HILS system for EHB(Electro-Hydraulic Brake) systems that include a high pressure generator and a valve control system that independently modulates the brake pressures at four wheels. An EHB control logic was tested in the HILS system. Test results under various driving conditions are presented and compared with the VDC logic.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.3
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• pp.86-91
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• 2020

An important factor of rough road modeling is analyzing the shear behavior properties of the rough road. These properties influence the drawbar pull of the tool when interacting with the soil used in agriculture. Furthermore, shear behavior properties are important because sinkage and shear stress are generated when wheels drive on rough roads. In this study, we performed a direct shear test to investigate the shear behavior properties of soils and compare with the direct shear simulation; shear force derived by the coupled analysis of discrete element method; and multi-body dynamics. Soil contact parameters were measured in a wheel and soil contact simulation followed by comparison of the simulated and experimentally measured shear force.

• Journal of Korean Critical Care Nursing
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• v.1 no.1
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• pp.59-71
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• 2008

Purpose: This study was to identify the effects of simulation-based training for advanced cardic life support on the competence of nurses in critical care settings. Methods: In this study, a nonequivalent control pretest-post test quasi-experimental design was used. Data were collected from May 1 to June 1, 2006 at one general hospital in W city. Among 40 nurses in critical care settings, twenty were assigned to the experimental group and twenty to the control group. Nurses in the experimental group received simulation-based training for advanced cardiac life support. Measurement tool were ACLS related knowledge and skills developed by AHA & Mega Code (2005) and some items were modified. The collected data were statistically processed using SPSS version 12.0 for Windows, and analyzed using descriptive statistics, $X^2$test, t-test, paired ttest, Pearson correlation coefficients. Results: 1) Hypothesis 1“: Nurses who received simulationbased training would have more knowledge of advanced cardiac life support than nurses who received traditional training”, was supported (t=11.51, p=.00). 2) Hypothesis 2: “Nurses who received simulation-based training would have better advanced cardiac life support skills than nurses who received traditional training”, was supported (t=2.38, p=.00). Conclusion: Simulation-based training for advanced cardiac life support is an effective strategy for increasing the competence of nurses in advanced cardiac life support in critical care settings.

• Journal of the Korean Society of School Health
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• v.24 no.1
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• pp.33-40
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• 2011

Purpose: The purpose of the study was to determine the effects of Simulation-Based Training on anxiety, depression and self-efficacy in nursing students. Methods: A quasi-experimental research design (one group pre-test and post-test design) and a questionnaire for measuring anxiety, depression and self-efficacy were used in this study. The participants were 97 students of a nursing college. Data were collected before the program and immediately after the program. Means, SD, paired t-test, and Cronbach's ${\alpha}$ with the SPSS/WIN 12.0 program were used to analyze the data. Results: There was a statistically significant decrease in anxiety (p=.012) and a statistically significant increase in self-efficacy (p=.048), but not in depression (p=.439) among the nursing students who underwent Simulation-Based Training. Conclusion: From the findings of this study, it was demonstrated that Simulation-Based Training interventions had effects on anxiety and self-efficacy. Therefore, future and/or repeat studies will actively apply Simulation-Based Training interventions.

• Smart Structures and Systems
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• v.28 no.6
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• pp.727-735
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• 2021

Recently, non-destructive health monitoring methods such as magnetic flux leakage (MFL) method, have become popular due to their advantages over destructive methods. Currently, numerical study on this field has been limited to simplified studies by only obtaining MFL instead of induced voltage inside coil sensor. In this study, it was proposed to perform a novel numerical simulation of MFL's coil sensor by considering vital parameters including specimen's motion with constant velocity and saturation status of specimen in time domain. A steel-rod specimen with two stepwise cross-sectional changes (i.e., 21% and 16%) was fabricated using low carbon steel. In order to evaluate the results of numerical simulation, an experimental test was also conducted using a magnetic probe, with same size specimen and test parameters, exclusively. According to comparative results of numerical simulation and experimental test, similar signal amplitude and signal pattern were observed. Thus, proposed numerical simulation method can be used as a reliable source to check efficiency of sensor probe when different size specimens with different defects should be inspected.

• Journal of the Korea Society for Simulation
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• v.19 no.3
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• pp.17-25
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• 2010

It is necessary for the ship dynamic models to realize ship dynamics and to achieve the real-time analysis in the manoeuvring simulation. Generally, simple dynamic models, such as 1st-order differential equation models of turning angle, turning rate, and forward speed, are used in the manoeuvring simulation for multiple ships. Ship dynamic modeling and parameter estimation methods based on its turning test results are proposed in this paper. Parameter estimation methods for the constant speed model and the speed-changing model are mathematically developed and verified by comparing with turning test results of a real ship.

• Journal of Integrative Natural Science
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• v.15 no.1
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• pp.9-18
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• 2022

This research examines the power of bootstrap two-sample test, and compares it with the powers of two-sample t-test and Wilcoxon rank sum test, through simulation. For simulation work, a positively skewed and heavy tailed distribution was selected as a population distribution, the chi-square distributions with three degrees of freedom, χ²₃. For two independent samples, the fist sample was selected from χ²₃. The second sample was selected independently from the same χ²₃ as the first sample, and calculated d+ax for each sampled value x, a randomly selected value from χ²₃. The d in d+ax has from 0 to 5 by 0.5 interval, and the a has from 1.0 to 1.5 by 0.1 interval. The powers of three methods were evaluated for the sample sizes 10,20,30,40,50. The null hypothesis was the two population medians being equal for Bootstrap two-sample test and Wilcoxon rank sum test, and the two population means being equal for the two-sample t-test. The powers were obtained using r program language; wilcox.test() in r base package for Wilcoxon rank sum test, t.test() in r base package for the two-sample t-test, boot.two.bca() in r wBoot pacakge for the bootstrap two-sample test. Simulation results show that the power of Wilcoxon rank sum test is the best for all 330 (n,a,d) combinations and the power of two-sample t-test comes next, and the power of bootstrap two-sample comes last. As the results, it can be recommended to use the classic inference methods if there are widely accepted and used methods, in terms of time, costs, sometimes power.

• Journal of the Korea Society for Simulation
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• v.27 no.1
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• pp.111-117
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• 2018

It is indispensable for a missile to track a target under the flight condition since the tracking capability affects the system performance considerably. The best way to verify the tracker's performance is flight test while it costs too much. Consequently, captive flight test or CFT has an important role in the development of a missile system. CFT, however, cannot simulate missile dynamics and is an offline and open-loop test. In this paper, we propose a new integrated-flight simulation(IFS) method using CFT imagery to overcome the limitation of synthetic image-based IFS method. This method increases the utilization of CFT's outputs and compensates the reality of imagery which lacks in the synthetic image-based IFS. Using this method make it possible to verify the system capability in various simulation modes.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.519-528
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• 2021

This study was conducted to examine the convergence effects of a simulation-based handoff training program on nursing students' handoff performance ability and handoff confidence. A quasi-experimental study of pre and post-experimental design was performed on 104 nursing college students located in P city and A city and the developed simulation-based handoff training program was implemented for 2 weeks from October 30 to November 10, 2017. The collected data were analyzed using the SPSS WIN 21.0 program with x² test, Fisher's exact test, independent t-test, ANCOVA with pretest value as covariate. The experimental group had significantly different handoff Performance Ability in comparison to the control group. The simulation-based handoff training program can be used as an effective handoff training program to enhance the handoff performance ability of nursing students.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.2
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• pp.76-82
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• 2018

A test simulator is needed to develop a fuel quantity measurement system that takes into account the roll and pitch motion of the aircraft. In this paper, we develop a test simulator that consists of attitude simulation equipment, fueling equipment, and data storage equipment. The attitude simulation equipment simulates the aircraft attitude. It is manufactured to operate pitch angle and roll angle movement. The fueling equipment supplies fuel to the supplementary fuel tank. The data storage equipment collects and stores the measured data. We also develop an automation software that operates the test simulator and collects data automatically. The test simulator has been automated to prevent testers from being exposed to toxic fuel. Through automation software, the collection period is reduced by one quarter compared to manual collection. The developed fuel quantity measurement system is verified through the test simulator.