• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.228-237
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• 2019

The crack growth responses of as-received and as-welded Alloy 600/182 and Alloy 690/152 welds to constant loading were measured by a direct current potential drop method using compact tension specimens in primary water at $325^{\circ}C$ simulating the normal operating conditions of a nuclear power plant. The as-received Alloy 600 showed crack growth rates (CGRs) between $9.6{\times}10^{-9}mm/s$ and $3.8{\times}10^{-8}mm/s$, and the as-welded Alloy 182 had CGRs between $7.9{\times}10^{-8}mm/s$ and $7.5{\times}10^{-7}mm/s$ within the range of the applied loadings. These results indicate that Alloys 600 and 182 are susceptible to cracking. The average CGR of the as-welded Alloy 152 was found to be $2.8{\times}10^{-9}mm/s$. Therefore, Alloy 152 was proven to be highly resistant to cracking. The as-received Alloy 690 showed no crack growth even with an inhomogeneous banded microstructure. The cracking mode of Alloys 600 and 182 was an intergranular cracking; however, Alloy 152 was revealed to have a mixed (intergranular + transgranular) cracking mode. It appears that the Cr concentration and the microstructural features significantly affect the cracking resistance and the cracking behavior of Ni-base alloys in PWR primary water.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.118-124
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• 2021

The article examines the formation of a competitive paradigm of economic security of industrial enterprises in the formation of a circular economy. The basic laws of industrial enterprises are formed, which determined the characteristics of competitive positions and threats. The basic competitive concepts and their application at maintenance of economic safety of the industrial enterprises in the conditions of formation of circular economy are described. Thus, the technological approach to the formation of a competitive paradigm is based on production technologies, opportunities for technological modernization and development of infrastructure and intellectual competencies. The institutional concept reveals the regulatory mechanisms for ensuring competitiveness through the protectionism of national industrial enterprises, standardization and regulation of market imbalances. The innovation-investment approach within the competitive paradigm is also manifested in the creation of competitive advantages due to the presence of active innovative developments and their commercialization, knowledge and competencies of staff, capitalization of intelligence and communications, constant updating of infrastructure and technologies. Collectively, innovation and investment effects on the level of economic security allow industrial enterprises to ensure resilience to increasing competition, the emergence of new market challenges in the formation of a circular economy. A strategic approach to the application of a competitive paradigm to ensure the economic security of industrial enterprises allows you to justify the prospects for development and design behavioral models to predict and assess potential threats. The concept of system management is based on the complexity of threat analysis, the integrity of the economic security system, system-forming functions and patterns of implementation of industrial development tasks in the formation of a circular economy. The application of the described concepts is formalized by the authors through the definition of the basic patterns, directions and characteristics of their impact on the elements of the security system of industrial enterprises in the formation of a circular economy.

• Advances in concrete construction
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• v.11 no.5
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• pp.429-445
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• 2021

With regard to economic efficiency, composite fix beams are widely used to pass longitudinal shear forces across the interface. The current knowledge of the composite beam load-slip activity and shear capability are restricted to data from measurements of push-off. Modelling and analysis of the composite beams based on Euro-code 4 regarding to shear, bending, and deflection under differing loads were carried out using Finite Element through an efficient computer simulation and the final loading and sections capacity based on the failure modes was analysed. In bending, the section potential was increased by an improvement of the strength in both steel and concrete, but the flexural and compressive resistance growth is very weak (3.2% 3.1% and 3.0%), while the strength of the concrete has increased respectively from 25 N/mm² to 30, 35, and 40 N/mm² compared to the increment of steel strength by 27% and 21% when it was raised from 275 to 355 and 460 N/mm², respectively. It was found that the final flexural load capacity of fix beams was declined with increase in the fix beam span for both three steel strength. The shear capacity of sections was remained unchanged at constant steel strength and different length, but raised with final yield strength increment of steel sections by 29%, and 67% when it was raised from 275 N/mm² to 355 N/mm² and 460 N/mm², respectively.

• Journal of the Korea Convergence Society
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• v.13 no.4
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• pp.613-623
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• 2022

Hospital textile is a necessary which the patient used everyday, that required constant management between supply and consumption. This study applied the service blue print technique to analyze how to provide and supply hospital textile from the stock to the patients in a tertiary hospital, Seoul, South Korea. There are actual or potential process problems identified such as nurses' increasing workload, patient dissatisfaction, and infection risk. After applying blueprint analysis, we suggest the modified processes to overcome theses identified problems using automatization to provide textile. Expected outcomes may include decreases in patient's waiting time, nurse's textile workload, and lower infection risk as well as increasing process efficiency via systematic supply-demand management.

• Journal of information and communication convergence engineering
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• v.20 no.1
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• pp.22-30
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• 2022

The reinforcement learning algorithm has proven its potential in solving sequential decision-making problems under uncertainties, such as finding paths to route data packets in wireless sensor networks. With reinforcement learning, the computation of the optimum path requires careful definition of the so-called reward function, which is defined as a linear function that aggregates multiple objective functions into a single objective to compute a numerical value (reward) to be maximized. In a typical defined linear reward function, the multiple objectives to be optimized are integrated in the form of a weighted sum with fixed weighting factors for all learning agents. This study proposes a reinforcement learning -based routing protocol for wireless sensor network, where different learning agents prioritize different objective goals by assigning weighting factors to the aggregated objectives of the reward function. We assign appropriate weighting factors to the objectives in the reward function of a sensor node according to its hop-count distance to the sink node. We expect this approach to enhance the effectiveness of multi-objective reinforcement learning for wireless sensor networks with a balanced trade-off among competing parameters. Furthermore, we propose SDN (Software Defined Networks) architecture with multiple controllers for constant network monitoring to allow learning agents to adapt according to the dynamics of the network conditions. Simulation results show that our proposed scheme enhances the performance of wireless sensor network under varied conditions, such as the node density and traffic intensity, with a good trade-off among competing performance metrics.

• Korean Journal of Materials Research
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• v.32 no.1
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• pp.14-22
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• 2022

To improve light absorption ability in the visible light region and the efficiency of the charge transfer reaction, Pd nanoparticles decorated with reduced TiO₂ nanotube photocatalyst were synthesized. The reduced TiO₂ nanotube photocatalyst was fabricated by anodic oxidation of Ti plate, followed by an electrochemical reduction process using applied cathodic potential. For TiO₂ photocatalyst electrochemically reduced using an applied voltage of -1.3 V for 10 min, 38% of Ti⁴⁺ ions on TiO₂ surface were converted to Ti³⁺ ion. The formation of Ti³⁺ species leads to the decrease in the band gap energy, resulting in an increase in the light absorption ability in the visible range. To obtain better photocatalytic efficiency, Pd nanoparticles were decorated through photoreduction process on the surface of reduced TiO₂ nanotube photocatalyst (r10-TNT). The Pd nanoparticles decorated with reduced TiO₂ nanotube photocatalyst exhibited enhanced photocurrent response, and high efficiency and rate constant for aniline blue degradation; these were ascribed to the synergistic effect of the new electronic state of the TiO₂ band gap energy induced by formation of Ti³⁺ species on TiO₂, and by improvement of the charge transfer reaction.

• Geophysics and Geophysical Exploration
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• v.24 no.4
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• pp.164-170
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• 2021

Frequency-domain and time-domain induced polarization methods can provide spectral information about subsurface media. Analysis of spectral characteristics has been studied mainly in the frequency-domain, however, time-domain induced polarization research has recently become popular. In this study, assuming a homogeneous half-space model, an inversion method was developed to extract Cole-Cole parameters from the measured secondary potential or electrical resistivity. Since the Cole-Cole parameters of chargeability, time constant, and frequency index are not independent of each other, various problems, such as slow convergence rate, initial model problem, local minimum problem, and divergence, frequently occur when conventional nonlinear inversion is applied. In this study, we developed an effective inversion method using the initial model close to the true model by introducing a grid search method. Finally, the validity of the developed inversion method was verified using inversion experiments.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.280-287
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• 2021

Generating electricity by using water in many energy harvesting system is due to their simplicity, sustainability and eco-friendliness. Evaporation-driven moist-electric generators (EMEGs) are an emergent technology and show great potential for harvesting clean energy. In this study, we report a transpiration driven electro kinetic power generator (TEPG) that utilize capillary flow of water in an asymmetrically wetted cotton fabric coated with carbon black. When water droplets encounter this textile EMEG, the water flows spontaneously under capillary action without requiring an external power supply. First carbon black sonicated and dispersed well in three different solvent system such as dimethylformamide (DMF), sodiumdedecylbenzenesulfonate (SDBS-anionic surfactant) and cetyltrimethylammoniumbromide (CTAB-cationic surfactant). A knitted cotton/PET fabric was coated with carbon black by conventional pad method. Cotton/PET fabrics were immersed and stuttered well in these three different systems and then transferred to an autoclave at 120 ℃ for 15 minutes. Cotton/PET fabric treated with carbon black dispersed in DMF solvent generated maximum current up to 5 µA on a small piece of sample (2 µL/min of water can induce constant electric output for more than 286 hours). This study is high value for designing of electric generator to harvest clean energy constantly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.2
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• pp.121-128
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• 2022

The aims of this study were to optimize the processing procedure of high-quality semi-alternating temperature dried Israeli carp Cyprinus carpio (SAD-IC) and to investigate the sensory properties of the product. Based on the differences in moisture content of the dorsal and ventral muscles, high quality SAD-IC was prepared by alternating the drying temperature between 4 h at 35℃, and 2 h at 5℃, three times before final drying for 2 h at 35℃. The surface in SAD-IC produced under the optimal alternating-temperature drying process had a markedly superior browning index value and softer texture compared to products produced using constant-temperature drying. SAD-IC produced from dorsal and ventral muscle had significantly superior taste values than the raw material. These results suggest that SAD-IC has the potential to be industrialized.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.5
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• pp.397-404
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• 2022

Fesoterodine, an antimuscarinic drug, is widely used to treat overactive bladder syndrome. However, there is little information about its effects on vascular K⁺ channels. In this study, voltage-dependent K⁺ (Kv) channel inhibition by fesoterodine was investigated using the patch-clamp technique in rabbit coronary artery. In whole-cell patches, the addition of fesoterodine to the bath inhibited the Kv currents in a concentration-dependent manner, with an IC₅₀ value of 3.19 ± 0.91 μM and a Hill coefficient of 0.56 ± 0.03. Although the drug did not alter the voltage-dependence of steady-state activation, it shifted the steady-state inactivation curve to a more negative potential, suggesting that fesoterodine affects the voltage-sensor of the Kv channel. Inhibition by fesoterodine was significantly enhanced by repetitive train pulses (1 or 2 Hz). Furthermore, it significantly increased the recovery time constant from inactivation, suggesting that the Kv channel inhibition by fesoterodine is use (state)-dependent. Its inhibitory effect disappeared by pretreatment with a Kv 1.5 inhibitor. However, pretreatment with Kv2.1 or Kv7 inhibitors did not affect the inhibitory effects on Kv channels. Based on these results, we conclude that fesoterodine inhibits vascular Kv channels (mainly the Kv1.5 subtype) in a concentration- and use (state)-dependent manner, independent of muscarinic receptor antagonism.