• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.472-485
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• 2019

When wood plastic composites (WPCs) have been used for a certain period of time, they become waste materials and should be recycled to reduce their environmental impact. Waste WPCs can be transformed into reinforced composites, in which fillers are used to improve their performance. In this study, recycled WPCs were prepared using different proportions of waste WPCs, nanoclay, and glass fiber. The effects of nanoclay and glass fiber on the microstructural, mechanical, thermal, and water absorption properties of the recycled WPCs were investigated. X-ray diffraction showed that the nanoclay intercalates in the WPCs. Additionally, scanning electron micrographs revealed that the glass fiber is adequately dispersed. According to the analysis of mechanical properties, the simultaneous incorporation of nanoclay and glass fiber improved both tensile and flexural strengths. However, as the amount of fillers increases, their dispersion becomes limited and the tensile and flexural modulus were not further improved. The synergistic effect of nanoclay and glass fiber in recycled WPCs enhanced the thermal stability and crystallinity ($X_c$). Also, the presence of nanoclay improved the water absorption properties. The results suggested that recycled WPCs reinforced with nanoclay and glass fiber improved the deteriorated performance, showing the potential of recycled waste WPCs.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.11-21
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• 2022

The perspectives on aging women's financial security during their retirement years are based on their behavior, planning, and decision-making processes during their working years. Elderly women are considered vulnerable and have a longer life expectancy, lower-income, and limited financial understanding compared to males; therefore, drastic steps need to be taken to improve their financial stability and quality of life. The current study sought to determine the most important contributors to retired women's financial health by measuring the value of four factors/variables: capability, opportunity, willingness, and biopsychosocial. This study used a mixed model approach, with qualitative analysis in the first phase involving a focus group discussion session, a pilot analysis, and quantitative analysis for phase two involving the distribution and collection of questionnaires completed by retired women. The surveys were distributed across Malaysia in five distinct zones and yielded 339 usable replies to support the theory. The outcomes of the Multiple Regression Analysis in Malaysia revealed that capability, opportunity, and biopsychosocial factors are significant predictors of retired women's financial security, whereas the willingness indicator lacked statistical significance.

• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.61-70
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• 1987

Authors have isolated phages of V. parahaemolyticus from shellfish and investigated some of their characteristics. The results obtained were as follows: Twenty-three phage strains(9.2%) out of 250 specimens were isolated. Plaques of phages were small, clear or turbid and $0.5{\sim}1.5mm$ in diameter. The electron micrographs of K3 phages showed two morphology; one was a hexagonal head about 105nm with a tail about 12nm, the other was a hexagonnal head about 60nm with a tail about 25nm. The host ranges of pahges were limited to V. parahaemolyticus strains and there appeared to be no relationship between the K serotypes of V. parahaemolyticus strains and the host ranges of the phage isolates. The adsorption rate of phages were more than 80% for $10{\sim}15$ minutes, the inactivation rate at $60^{\circ}C$ was more than 99% for $40{\sim}45$ minutes. The pH stability range was between 6.0 and 8.0. The inactivation rate of phages by UV irradiation was more than 99% for $45{\sim}75$ seconds.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.347-355
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• 2011

Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.

• Applied Science and Convergence Technology
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• v.23 no.2
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• pp.72-82
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• 2014

Lithium-ion batteries (LIBs) have become popular electrochemical devices. Due to the unique advantages of LIBs in terms of high operating voltage, high energy density, low self-discharge, and absence of memory effects, their application range, which was primarily restricted to portable electronic devices, is now being extended to high-power applications, such as electric vehicles (EVs) and hybrid electrical vehicles (HEVs). Among various anode materials, $Li_4Ti_5O_{12}$ (LTO) is believed to be a promising anode material for high-power LIBs due to its advantages of high working potential and outstanding cyclic stability. However, the rate performance of LTO is limited by its intrinsically low electronic conductivity and poor $Li^+$ ion diffusion coefficient. This review highlights the recent progress in improving the rate performance of LTO through doping, compositing, and nanostructuring strategies.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.249-261
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• 2021

To tranquilize the devastating impact of unnecessary risk-taking behavior of banks towards the economy for maximizing their profits that usually arises due to widely known 'moral-hazard' problem originating from market competition and intensified by bank's limited liability, the banking system is strongly monitored across all countries of the world. The goal of controlling would become more feasible if there exist some self-discipline and motivations which could safeguard the banks' charter value through the mechanism of market discipline. Therefore, our study is aimed to scrutinize the relation between market discipline and charter value of local commercial banks that are registered on the Pakistan Stock Exchange by analyzing a balanced panel data from the year 2007 to 2019. Deposit growth, interbank deposits, and subordinate debt are taken as proxies to measure market discipline whereas Tobin's Q theory is applied for calculating the charter value. Generalized Least Square Regression with Fixed Effect Model is used for evaluation. The outcomes reveal that in the existence of control variables, all proxies of market discipline have a significant positive impact on bank charter value. Our research has important policy implications for monitoring and supervising financial intermediaries for their stability and soundness by offsetting the complications of moral-hazard in the financial systems.

• The Journal of Korean Physical Therapy
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• v.29 no.4
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• pp.201-206
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• 2017

Purpose: The aim of this study was to identify the effects of Pilates mat exercise may improve trunk muscle thickness and balance in healthy adults. Methods: Eighteen healthy adults participated in this study. They were randomly assigned to one of two groups: Pilates mat exercise group (n=9) and the control group (n=9). Subjects in Pilates mat exercise group performed the exercises three days per week for 6 weeks, which consisted of warm up, main workout, and cool down. Trunk muscle thickness of the rectus abdominis (RA), internal oblique (IO), external oblique (EO), transverse abdominis (TrA), multifidus (MF), and erector spine (ES) were measured using an ultrasonography. Balance ability was evaluated using Romberg test and limits of stability (LOS). Measurements were performed before training, 3 weeks after training, and 6 weeks after training. Results: There was a significant difference of RA, EO, IO, MF, and ES according to the main effect of time (p<0.05). There was a significant difference of EO, MF, ES, Romberg, and LOS according to interaction effect between the time and group (p<0.05). There was a significant difference only for LOS according to the main effect of the group (p<0.05). Conclusion: Pilates mat exercise did increase trunk muscle thickness and balance. However, the effect with respect to trunk thickness was limited. Pilates mat exercise appears to be more effective in improving muscles related to trunk extension and balance.

• Membrane and Water Treatment
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• v.11 no.3
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• pp.231-235
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• 2020

Industrialization and modern developments have led to an influx of toxic heavy metals into the aquatic environment, and the accumulation of heavy metals has serious adverse effects on humans. Among the various heavy metal treatment methods, adsorption is very useful and frequently used. Plastic materials, such as polypropylene and polyethylene, have been widely used as filter media due to their mechanical and chemical stability. However, the surface of plastic material is inert and therefore the adsorption capability of heavy metals is very limited. In this study, granular media and fiber media composed of polypropylene and polyethylene are used, and the surface modification was conducted in order to increase adsorption capability toward heavy metals. Oxygen plasma generated hydroxyl groups on the surface of the media to activate the surface, and then acrylic acid was synthesized on the surface. The grafted carboxyl group was confirmed by FT-IR and SEM. Heavy metal adsorption capability of pristine and surface modified adsorbents was also evaluated. Overall, heavy metal adsorption capability was increased by surface modification due to electrostatic interaction between the carboxyl groups and heavy metal ions. Fibrous PP/PE showed lower improvement compared to granular PP media because pore blockage occurred by the surface modification step, thereby inhibiting mass transfer.

• Journal of the Korean Electrochemical Society
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• v.13 no.1
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• pp.45-49
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• 2010

The rechargeable Zn-air battery is considered as one of the potential candidates for the next generation secondary batteries due to its many advantages. However, its further applications and commercialization have been limited by the complexity of the reactions on air electrode which are oxygen reduction and evolution reactions (ORR/OER) upon discharging and charging processes, respectively. In the present study, lanthanum was impregnated into a commercial Pt/C gas diffusion electrode, and it clearly verified significantly enhanced cycling stability and reversibility. The results presented in this study show the possibility of repeated charge/discharge processes for Zn-air batteries with a La-loaded air electrode, and they demonstrate the potential as a promising next generation secondary battery.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.9
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• pp.1-7
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• 2011

A performance delivers the contents and feeling through human bodies and stage settings in the limited space of a stage. Among the stage settings, the lighting creates overall atmospheres effectively according to the situations of the performance such as a time flow, a change of seasons, an expression of the mental state of the performer. As the LED lighting is used more widely, the number and the size of the lighting is being decreased, which makes it possible for various devices to be used. However, just as conventional lighting devices, most of them are fixed. So it is difficult to use them at a blind spot and to replace them. To solve this problem, this article suggests a system which replaces lighting automatically and moves. As it can moved to a spot we want on a rail, and the lighting system can be replaced by itself, it can have various lighting effects, increasing the effectiveness of the performance. Additionally, it can also decrease the danger of a worker operating the lighting device located at a high place. At the mock-up experiment, its mobility and stability on a rail were tested using the wheel of the Modular Robot.