• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.102-107
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• 2005

PMS(Plant Monitoring System) for simulation is the program for training that users such as instructor, operator, and supervisor can operate the plant virtually. Presented in this paper, are some lessons learned from implementation of PMS for simulation. First, this PMS fer simulation is based on LINUX instead of UNIX. These two OS(Operating System) have different platform and compiler version on it, so debugging needs to be done about variable defining part. Second, In LINUX system, the size of shared memory and message queue is already designated as a default value that user has to set up and use the RTAP DB. Third, to decrease the dummy data size, it has to be changed into binary formation. Lastly, PMS software for simulation provides several environments according to the command, so considered should be status monitoring, alarm, system organization, point and group monitoring, history storage and searching function.

• Environmental Engineering Research
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• v.12 no.5
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• pp.211-217
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• 2007

Polycyclic aromatic hydrocarbon growth from cyclopentadiene (CPD) pyrolysis was investigated using a laminar flow reactor operating in a temperature range of 600 to $950^{\circ}c$. Major products from CPD pyrolysis are benzene, indene and naphthalene. Formation of observed products from CPD is explained as follows. Addition of the cyclopentadienyl radical to a CPD $\pi$-bond produces a resonance-stabilized radical, which further reacts by one of three unimolecular channels: intramolecular addition, C-H bond $\beta$-scission, or C-C bond $\beta$-scission. The intramolecular addition pathway produces a 7-norbornenyl radical, which then decomposes to indene. Decomposition by C-H bond $\beta$-scission produces a biaryl intermediate, which then undergoes a ring fusion sequence that has been proposed for dihydrofulvalene-to-naphthalene conversion. In this study, we propose C-C bond $\beta$-scission pathway as an alternative reaction channel to naphthalene from CPD. As preliminary computational analysis, Parametric Method 3 (PM3) molecular calculation suggests that intramolecular addition to form indene is favored at low temperatures and C-C bond $\beta$-scission leading to naphthalene is predominant at high temperatures.

• Journal of The Korean Astronomical Society
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• v.55 no.6
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• pp.215-220
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• 2022

To seek an atmospheric heating mechanism operating on the Sun we investigated a heating source generated by a downflow, both of which may arise in a magnetic loop dynamically formed on the Sun via flux emergence. Since an observation shows that the illumination of evolving magnetic loops under the dynamic formation occurs sporadically and intermittently, we performed a magnetohydrodynamic simulation of flux emergence to obtain a high-cadence simulated data, where temperature enhancement was identified at the footpoint of an evolving magnetic loop. Unlike a rigid magnetic loop with a confined flow in it, the evolving loop in a low plasma β atmosphere is subjected to local compression by the magnetic field surrounding the loop, which drives a strong supersonic downflow generating an effective footpoint heating source in it. This may introduce an energy conversion system to the magnetized atmosphere of the Sun, in which the free magnetic energy causing the compression via Lorentz force is converted to the flow energy, and eventually reduced to the thermal energy. Dynamic and thermodynamic states involved in the system are explained.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.57-64
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• 2007

RIMS（Rolling Stock Information Maintenance System)　was installed in structure which it can analyze the data base in need of credibility maintenance. So it could accumulate real data without repulsion of working spot. Information system was installed not following to system but following to working spot. The development of RIMS project was started from March 29, 2001 and it has been operating from October 12, 2004 in Chang-dong Car depot for light maintenance in charge subway line4. So substantial data base was accumulated for three years. This study calculated all RAMS data by analyzing data base accumulated in RIMS and used in dada base about credibility maintenance and found investigation of propriety, expectation of the life cycle cost, the improvement plan on credibility of sorts of cars and formation about the cycle of repairing and maintenance. This got MKBSF MKBF and MTBF about devices and sorts of line4 Rolling Stocks for it.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.143-150
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• 2007

RIMS（Rolling Stock Information Maintenance System)　was installed in structure which it can analyze the data base in need of credibility maintenance. So it could accumulate real data without repulsion of working spot. Information system was installed not following to system but following to working spot. The development of RIMS project was started from March 29, 2001 and it has been operating from October 12, 2004 in Chang-dong Car depot for light maintenance in charge subway line4. So substantial data base was accumulated for three years. This study calculated all RAMS data by analyzing data base accumulated in RIMS and used in dada base about credibility maintenance and found investigation of propriety, expectation of the life cycle cost, the improvement plan on credibility of sorts of cars and formation about the cycle of repairing and maintenance. This got MKBSF MKBF and MTBF about devices and sorts of line4 Rolling Stocks for it.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3949-3956
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• 2022

Kori Unit 1 is planning a system decontamination project to reduce radiation exposure of decommissioning workers, prevent the spread of contamination and down-grade the level of classification of radioactive waste. The system decontamination range for Kori Unit 1 will be the entire primary system, including RCS, CVCS and RHRS. Some system design modifications are required for the system decontamination operation. In this paper, major system design modifications were evaluated based on the conditions that system restoration is needed after completion of system decontamination. The major system design modifications are CIDF connection location to system, system decontamination operating pressure control, RCP seal water injection and formation of letdown flow. It was evaluated that there was no negative effect on the system due to the system design modifications. However, as the RCP seal water is injected into the system in the oxidation process, the concentration of the oxidizing agent is diluted. Therefore, the oxidizing agent injection and system decontamination operation procedures should be developed to address the dilution effect of the oxidizing agent. The system design modifications dealt in this paper will be finally confirmed through on-site investigation in the future, and if necessary, the system design modifications will be re-evaluated.

• Journal of Fisheries and Marine Sciences Education
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• v.18 no.3
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• pp.229-235
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• 2006

This study investigated physiology and psychological response of subjects, when heat pump was operated long time within comfort temperature range. Eight subjects were participated for the experiment. Their age was from 22 to 25 years old. The results of this experiment will propose basic data for improving comfort control algorithm in fluctuating environment by using heat pump. When indoor temperature was controlled by heat pump, the conclusion was as follows. 1) When votes of subjects was considered, the thermal comfort neutrality or lower range helped formation of comfort sensation for subjects. 2) When room temperature was lower, thermal comforts of shoulder, knee and foot with subjects thermal comfort showed high correlation. And when room temperature was higher, thermal comfort of face region with subjects thermal comfort showed high correlation. 3) The necessity of temperature change after 50 minutes from initially operating heat pump demands the additional analysis against the physiological signal.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.385-395
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• 2009

In this study, a series of numerical analysis has been accomplished on the thermal performance and sectional efficiency of a closed-loop vertical ground heat exchanger (U-loop) in a geothermal heat pump system (GHP) considering the circulating fluid, pipe, grout and soil formation. A finite element analysis program, ABAQUS, was employed to evaluate the temperature distribution on the cross section of the U-loop system involving HDPE pipe/grout/formation and to compare sectional efficiency between the conventional U-loop and a new latticed HDPE pipe system. Especially, the latticed pipe is equipped with a thermal insulation zone in order to reduce thermal interference between the inflow pipe and the outflow pipe. Also, a thermal stress analysis was performed with the aid of ABAQUS. 3-D finite volume analysis program, FLUENT, was adapted to analyze a coupled system between fluid circulation in the pipe and heat transfer and simulate an operating process of the closed-loop vertical ground heat exchanger. In this analysis, the effect of the thermal properties of grout, rate of circulation pump, distance between the inflow pipe and the outflow pipe, and the effectiveness of the latticed HDPE pipe system are taken into account.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.5
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• pp.443-454
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• 1998

Pt-V catalytic converter was installed on a heavy duty diesel engine and the characteristics of the emission reduction were tested using a engine dynamometer at various operating conditions. The emission reduction performance of Pt-V catalyst was also compared with that of a commercialized Pt catalyst currently being used in some of the heavy duty diesel engines in advanced countries. The effects of Pt-V and Pt catalysts on regulated and unregulated emissions were investigated using a 0.05 weight percent sulfur content fuel with an engine dynamometer Experiments for gaseous emissions (CO, HC and aldehyde) as well as particulate emissions (TPM, SOF and sulfate) have been conducted at several operating conditions such as T-7 mode, D-13 mode and S-13 mode before and after installing the Pt-V and Pt catalysts in the exhaust system. The emission reduction performance of Pt catalyst with respect to CO, HC, SOF, PAHs and aldehyde was found to be a little higher than that of Pt-V catalyst, but the Pt catalyst showed innate disadvantage of causing an increase of PM due to the sulfate formation via high SO2 conversion at high exhaust temperature, especially above 45$0^{\circ}C$.

• Journal of ILASS-Korea
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• v.17 no.3
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• pp.146-151
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• 2012

This study was primarily focused on the experimental comparison of the particle emission characteristics for heavy duty engine. PM and particle number from various heavy duty engines and DPF type were analyzed with a golden particle measurement system recommended by the Particle Measurement Program. And the repeatability and reproducibility between test mode was analyzed. This study was conducted for the experimental comparison on particulate emission characteristics between the European and World-Harmonized test cycles for a heavy-duty diesel engine. To verify the particulate mass and particle number concentrations from various operating modes, ETC/ESC and WHTC/WHSC, both of which will be enacted in Euro VI emission legislation, were evaluated. Real-time particle formation of the transient cycles ETC and WHTC were strongly correlated with engine operating conditions and after-treatment device temperature. A higher particle number concentration during the ESC mode was ascribed to passive DPF regeneration and the thermal release of low volatile particles at high exhaust temperature conditions.