• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.413-417
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• 2018

The $Li_4Ti_5O_{12}$ of anode material for the hybrid capacitor was coated using $CePO_4$, $M_3(PO_4)_2$ (M=Mg, Zn). The capacitance of phosphate coated $Li_4Ti_5O_{12}$ was found to be lower than that of $Li_4Ti_5O_{12}$, whereas the equivalent series resistance was higher than that of $Li_4Ti_5O_{12}$. With an increase in cycle number, the base of cylindrical cell exhibited swelling due to gas generated from the reaction between $Li_4Ti_5O_{12}$ and electrolyte. The swelling cycle number of phosphate coated $Li_4Ti_5O_{12}$ was higher than that of $Li_4Ti_5O_{12}$ due to improvement in electrochemical stability. Based on the results, it is proposed that phosphate coating can be employed as a barrier layer to control the gassing reaction by isolating the $Li_4Ti_5O_{12}$ particle from electrolyte solution.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.2
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• pp.117-124
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• 2017

Densities of molten salt mixtures of eutectic LiCl-KCl with $UCl_3$, $CeCl_3$, or $LaCl_3$ at various concentrations (up to 13 wt%) were measured using a liquid surface displacement probe. Linear relationships between the mixture density and the concentration of the added salt were observed. For $LaCl_3$ and $CeCl_3$, the measured densities were significantly higher than those previously reported from Archimedes' method. In the case of $LiCl-KCl-UCl_3$, the data fit the ideal mixture density model very well. For the other salts, the measured densities exceeded the ideal model prediction by about 2%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.149-150
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• 2011

Recently, Goverment's Energy-saving policy in Korea as 'Green Growth' is very remarkable effort. By intensive poliicies, the private is encouraged to participate in policy. Especially, it is very important in the field of architecture and we have to work for construction of law system. However, these efforts of the government buildings for energy efficiency in use stage is as mandatory system that may occur in the construction phase and the enviromental impact of greenhouse gas reductions is not affected. For this reason, Assess the amount of the energy consumption and CO₂ emissioont of Government Buildings in 2010 ordered by PPS(Public Procurement Service) in the construction phase and suggest to recognize the need for legal restrictions.

• Transactions of the Korean hydrogen and new energy society
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• v.1 no.1
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• pp.40-47
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• 1989

The sulfur-iodine thermochemical water splitting process of GA(General atomic) cycle was studied to produce hydrogen from water by $H_2-I_2-SO_2$ reactions. The experimental scale was 500g based on iodine. The reaction took 100 minutes, products could be separated two liquid phases due to their density difference:HI solution had a density of 2.39~2.61g/cc, and $H_2SO_4$ solution had 1.37~1.38g/cc. The condition of reaction was when weight ratio of $I_2/H_2O$ was 2/1 resulting in good phase separation and productivity.

• Smart Structures and Systems
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• v.29 no.5
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• pp.677-691
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• 2022

Water cycle algorithm (WCA) has been a very effective optimization technique for complex engineering problems. This study employs the WCA for simultaneous prediction of heating load (L_H) and cooling load (L_C) in residential buildings. This algorithm is responsible for optimally tuning a neural network (NN). Utilizing 614 records, the behavior of the L_H and L_C is explored and the captured knowledge is then used to predict for 154 unanalyzed building conditions. Since the WCA is a population-based algorithm, different numbers of the searching agents were tested to find the most optimum configuration. It was observed that the best solution is discovered by 500 agents. A comparison with five newly-developed benchmark optimizers, namely equilibrium optimizer (EO), multi-tracker optimization algorithm (MTOA), slime mould algorithm (SMA), multi-verse optimizer (MVO), and electromagnetic field optimization (EFO) revealed that the WCANN predicts the desired parameters with considerably larger accuracy. Obtained root mean square errors (1.4866, 2.1296, 2.8279, 2.5727, 2.5337, and 2.3029 for the L_H and 2.1767, 2.6459, 3.1821, 2.9732, 2.9616, and 2.6890 for the L_C) indicated that the most reliable prediction was presented by the proposed model. The EFONN, however, provided a more time-effective solution. Lastly, an explicit predictive formula was elicited from the WCANN.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.9
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• pp.1897-1904
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• 2002

Monotonic torsional and pure torsional low cycle fatigue(LCF) test with artificial degradation were performed on duplex stainless steel(CF8M). CF8M is used in pipes and valves in nuclear reactor coolant system. It was aged at 430$^{\circ}C$ for 3600hrs. Through the monotonic and LCF test, it is found that mechanical properties(i.e., yield strength, strain hardening exponent, strength coefficient etc.) increase and fatigue life(N$\sub$f/) decreases with degradation of material. The relationship between shear strain amplitude(${\gamma}$$\sub$a/)and N$\sub$f/ was proposed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.976-979
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• 2000

This paper describes a Life Cycle Engineering approach which is able to optimize a product under technical, ecological and economical requirements. The methodology of Life Cycle Engineering comes with a holistic approach for the analysis of processes, products, systems or services. The Life Cycle Engineering approach is combining environmental and economical parameters and using the technical requirements for setting the baseline for the studies. This paper also describes the approach method for ？ㄴ composed in large numbers sub-parts.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.647-661
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• 2015

The supercritical $CO_2$ (S-$CO_2$) Brayton cycle has recently been gaining a lot of attention for application to next generation nuclear reactors. The advantages of the S-$CO_2$ cycle are high efficiency in the mild turbine inlet temperature region and a small physical footprint with a simple layout, compact turbomachinery, and heat exchangers. Several heat sources including nuclear, fossil fuel, waste heat, and renewable heat sources such as solar thermal or fuel cells are potential application areas of the S-$CO_2$ cycle. In this paper, the current development progress of the S-$CO_2$ cycle is introduced. Moreover, a quick comparison of various S-$CO_2$ layouts is presented in terms of cycle performance.

• Journal of the Korean Society of Costume
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• v.63 no.8
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• pp.156-170
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• 2013

The purpose of this research is to scrutinize the cyclist's consumer behavior by analyzing the eWOM information search behavior of cycle-wear according to benefits sought and involvement. The research was conducted through an online survey and the respondents were 291 men who wore cycle-wear and searched information via online. The results of this research are as following. First, the benefits sought from wearing cycle apparel are composed of five sub-factors such as, ideal body figure, brand ostentation, comfort ease, personality, and economic feasibility. In addition, the cycle-wear involvement consisted of two sub-factors: cycling involvement and fashion involvement. Second, the eWOM information search behavior of cyclists was different depending on the benefits sought by the cyclists. When the cyclists pursued ideal body figure they searched more information of design and color, while cyclists put more weight on the information of design, color, and brand when they sought brand ostentation. Moreover, the valence and the type of the information were dissimilar depending on the benefits sought. Third, the sub-factors of eWOM information search behavior affected the eWOM effect distinctively. The price information was the only factor that influenced the eWOM effect among the contents of the information. The valence of the information influenced the eWOM effect, and the effect of positive information was stronger than negative information. Additionally, the subjective information also affected the eWOM effect. Lastly, the effect of the benefits sought influencing the eWOM information search behavior varied by the difference of the cycle-wear involvement. For example, when they are both high in the involvement there were various benefits sought affecting the eWOM information search behavior. However, when only the cycling involvement was high, and they pursued personality, the price information was not important to them.

• Transactions of the Korean hydrogen and new energy society
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• v.14 no.4
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• pp.298-304
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• 2003

The thermal behavior of $NiFe_2O_4$ prepared by a solid-state reaction was investigated for $H_2$ generation by the thermochemical cycle. The reduction of $NiFe_2O_4$ started from $800^{\circ}C$, and the weight loss was 0.2-0.3 wt% up to $1000^{\circ}C$. In the $H_2O$ decomposition reaction, $H_2$ was generated by oxidation of reduced $NiFe_2O_4$. The crystal structure of $NiFe_2O_4$ maintained during the redox reaction of 5 cycles. From this observation, the lattice oxygen in $NiFe_2O_4$ is released without the structural change during the thermal reduction and oxygen deficient $NiFe_2O_4$ can be restored to the spinel structure of $NiFe_2O_4$.