• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.10
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• pp.1293-1302
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• 1999

In this paper, an on-line process scheme is presented for implementation of a intelligent on-line modeling of nonlinear complex system. The proposed on-line process scheme is composed of FNN-based model algorithm and PLC-based simulator, Here, an adaptive fuzzy-neural networks and HCM(Hard C-Means) clustering method are used as an intelligent identification algorithm for on-line modeling. The adaptive fuzzy-neural networks consists of two distinct modifiable sturctures such as the premise and the consequence part. The parameters of two structures are adapted by a combined hybrid learning algorithm of gradient decent method and least square method. Also we design an interface S/W between PLC(Proguammable Logic Controller) and main PC computer, and construct a monitoring and control simulator for real process system. Accordingly the on-line identification algorithm and interface S/W are used to obtain the on-line FNN model structure and to accomplish the on-line modeling. And using some I/O data gathered partly in the field(plant), computer simulation is carried out to evaluate the performance of FNN model structure generated by the on-line identification algorithm. This simulation results show that the proposed technique can produce the optimal fuzzy model with higher accuracy and feasibility than other works achieved previously.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.14-20
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• 2017

A numerical study was conducted to identify the predictive performance for the bare-bead thermocouple (TC) using FDS (Fire Dynamics Simulator) in simulated thermal environments of fire. A relative prediction bias of TC temperature calculated from reverse-radiation correction by FDS was evaluated with the comparison of previous experimental data. As a result, it was identified that the TC temperatures predicted by FDS were lower than the temperatures measured by bare-bead TC for the ranges of heat flux and gas temperature considered. The relative prediction bias of TC temperature by FDS was gradually increased with the increase in radiative heat flux and also significantly increased with the decrease in the gas temperature. Quantitatively, at the gas temperature of $20^{\circ}C$, the TC temperature predicted by FDS had the relative bias of approximately -20% with the radiative heat flux of $20kW/m^2$ corresponding to thermal radiation level of the flashover. It is predicted from the present study that more accurate validation of fire modeling will be possible with the quantitative prediction bias occurred in the process of reverse-radiation correction of temperature predicted by FDS.

• Journal of Korean Academy of Nursing
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• v.43 no.2
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• pp.185-193
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• 2013

Purpose: Simulation-based learning has become a powerful method to improve the quality of care and help students meet the challenges of increasingly complex clinical practice settings. The purpose of this study was to identify the learning effects using high-fidelity SimMan and multi-mode simulation. Methods: Participants in this study were 38 students who were enrolled in an intensive course for a major in nursing at R college. Collected data were analyzed using Chi-square, t-test, and independent t-test with the SPSS 18.0 for Windows Program. Results: There were no statistically significant differences in learning effects between high-fidelity SimMan and multi-mode simulation group. However, skills in clinical performance in the high-fidelity SimMan group were higher than in the multi-mode group (p=.014), communication in clinical performance in multi-mode simulation group was higher than in the high-fidelity SimMan group (p<.001). Conclusion: Multi-mode simulation with a standardized patient is an effective learning method in many ways compared to a high-fidelity simulator. These results suggest that multi-mode simulation be offered to students in nursing colleges which cannot afford to purchase a high-fidelity simulator, or offered as an alternative.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.236-239
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• 2001

This paper provides a comprehensive study of the effect of time delay on adaptive transmission methods. By adaptive we mean that the transmission of data is made adaptive according to channel conditions. That is, the modulation level at the transmitter is carefully controlled for maximizing bandwidth efficiency, on the basis of the observation of instantaneous channel characteristics. By making use of the simulator developed for the present work, a large number of channel propagation environments including the models proposed in 3GPP were submitted to the simulator and the performance with respect to both time delay and SNR is observed. The results show that the performance is very sensitive to channel delay and in some cases the performance shows irreducible BER (IBER). A large amount of delay together with a high fading rate greatly affects the performance of adaptive transmission systems.

• The KIPS Transactions:PartC
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• v.11C no.1
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• pp.123-134
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• 2004

The synchronized clock performance in the synchronization network and SDH transmission network design is an important element in aspect of guaranteeing network stability and data transmission. Consequently the simulator which can applicable various parameters and several input levels from the best state to the worst state for performance analysis of the synchronized clock is required in case of network design. Therefore, in this paper, 1 developed the SNCA and TNCA for analysis of the synchronized clock in the synchronization network and transmission network. And utilizing these simulators with various wander generation, node number and clock state, 1 obtained the synchronized clock characteristics and maximum network nodes In NE1, NE2 and NE3 transmission network and DOTS1, DOTS2 synchronization network.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.94-101
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• 2014

We studied to investigate the erythema reduction effects generated by Gagam-Jawoonaek(GJ) application(appl.) after UV exposure. Twenty women in their twenties to fifties with no skin diseases were recruited. We exposed UV as a 6 subsites on the left upper arm of subjects using multi-port solar simulator. After setting Gagam-Jawoonaek(GJ) application(appl.) subsites and non-appl. subsites, we measured erythema degrees($a^*$ values) of the subsites using spectrophotometer. We measured $a^*$ values four times(before UV exposure, before application of GJ, twenty-four and forty-eight hours after first application of GJ). We analyzed data using student's t-test. After UV exposure, $a^*$ values on the left upper arm increased. Twenty-four hours after first GJ treat., the changes of $a^*$ value on GJ treat. subsites($1.22{\pm}0.13AU$) were bigger than GJ non-treat. subsites($1.04{\pm}0.12AU$), but there was no statistically significance. Forty-eight hours after first GJ treat., the changes of $a^*$ value on GJ treat. subsites($1.95{\pm}0.11AU$) were bigger than GJ non-treat. subsites($1.58{\pm}0.13AU$), a statistically significance. Gagam-Jawoonaek could decrease erythema by UV exposure.

• Journal of the Korean Institute of Navigation
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• v.20 no.1
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• pp.1-10
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• 1996

The assesment of the safety of ship's transit in a curved narrow channel consists of the maneuvering safety determined by the chance of running aground, the maneuvering difficulty determined by ship's workload, and shiphandler's subjective evaluation. In this study, to examine the correlation between shiphandler's subjective evaluation and the maneuvering safety, the real-time and full-mission shiphandling simulator in the Korea Marine Training & Research Institute(KMTRI) was utilized. On the conning bridge of the shiphandling simulator, 50 experienced masters have conducted the modeled vessel of 60, 000 deadweight tonnage along the designed channel under 3 different environmental conditions. It was possible to assess and analyze theoretically the correlation between the shiphandler's subjective evaluation and maneuvering difficulty under each environmental condition by quantifying the data obtained from the tests. The results are as follows: $\circled1$ As the degree of maneuvering difficulty increases, the shiphandler's subjective evaluation increases in the designed channel under the designed environmental condition. $\circled2$ In the straight area, not the bend of the designed channel, maneuvering difficulty increases sharply under the environmental condition of current and wind coming from the stern.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.159-166
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• 2006

Chassis system has a large influence on ride quality, stability and NVH performance of a car. To improve the performance and reduce cost, the development of chassis modular assemblies is emphasized. To develop chassis corner modules, it is necessary to predict the performance of full vehicle motion such as ride, handling performance, NVH characteristics and durability of modules. In this paper, full vehicle test is performed to acquire the road load data of chassis corner module of passenger car. 3-axis simulator modeling are carried out to simulate reaction force analysis and fatigue analysis of new developed modules. Also, real simulator tests to validate performance of new developed modules are performed. We had developed the accelerated durability test procedure of KATECH PG and it is used to test chassis corner modules at laboratory and simulate durability performance. All these results have been provided to module and parts company and make an important role to develop chassis corner modules.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.11
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• pp.1055-1060
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• 2006

High temperature superconducting(HTS) power cable is expected to be used for power transmission lines supplying electric power for densely populated cities in the near future. Since HTS power cable is capable of the high current density delivery with low power loss, the cable size can be compact comparing with the conventional cable whose capacity is same. In this paper, the authors propose the real time simulation method which puts a teal HTS wire into the simulated 22.9 kV utility grid system using Real Time Digital Simulator (RTDS). For the simulation analysis, test sample of HTS wire was actually manufactured. And the transient phenomenon of the HTS wire was analyzed in the simulated utility power grid. This simulation method is the world first trial in order to obtain much better data for installation of HTS power device into utility network.

• Nuclear Engineering and Technology
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• v.41 no.7
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• pp.969-978
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• 2009

The ASSERT-PV subchannel code developed by AECL has been applied as a design-assist tool to the advanced $CANDU^{(R)1}$ reactor fuel bundle. Based primarily on the $CANFLEX^{(R)2}$ fuel bundle, several geometry changes (such as element sizes and pitch-circle diameters of various element rings) were examined to optimize the dryout power and pressure-drop performances of the new fuel bundle. An experiment was performed to obtain dryout power measurements for verification of the ASSERT-PV code predictions. It was carried out using an electrically heated, Refrigerant-134a cooled, fuel bundle string simulator. The axial power profile of the simulator was uniform, while the radial power profile of the element rings was varied simulating profiles in bundles with various fuel compositions and burn-ups. Dryout power measurements are predicted closely using the ASSERT-PV code, particularly at low flows and low pressures, but are overpredicted at high flows and high pressures. The majority of data shows that dryout powers are underpredicted at low inlet-fluid temperatures but overpredicted at high inlet-fluid temperatures.