• Current Optics and Photonics
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• v.3 no.2
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• pp.177-180
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• 2019

Based on liquid-lens technology and our previous findings on the optical model of the Chinese eye, the liquid lens is applied in the research of the crystalline-lens optical model. Theoretical models of three-layer liquid lenses are built with COMSOL software, and the effect of voltage on the shape of the interface between two liquids is analyzed. By polynomial fitting, different equations describing the interface shape are set up under different voltages. Finally, the optical system of the human eye with a three-layer liquid lens is built and analyzed with Zemax optical design software, and moreover the optical system models of emmetropia, myopia, and hyperopia are presented. This method to build a model of the human eye with a variable-focus liquid lens can provide a novel idea for more practical human-eye models for clinical regulation and control in the future.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.1-14
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• 2019

Resveratrol was first isolated in 1939 by Takaoka from Veratrum grandiflorum O. Loes. Following this discovery, sporadic descriptive reports appeared in the literature. However, spurred by our seminal paper published nearly 60 years later, resveratrol became a household word and the subject of extensive investigation. Now, in addition to appearing in over 20,000 research papers, resveratrol has inspired monographs, conferences, symposia, patents, chemical derivatives, etc. In addition, dietary supplements are marketed under various tradenames. Once resveratrol was brought to the limelight, early research tended to focus on pharmacological activities related to the cardiovascular system, inflammation, and cancer but, over the years, the horizon greatly expanded. Around 130 human clinical trials have been (or are being) conducted with varying results. This may be due to factors such as disparate doses (ca. 5 to 5,000 mg/day) and variable experimental settings. Further, molecular targets are numerous and a dominant mechanism is elusive or nonexistent. In this context, the compound is overtly promiscuous. Nonetheless, since the safety profile is pristine, and use as a dietary supplement is prevalent, these features are not viewed as detrimental. Given the ongoing history of resveratrol, it is reasonable to advocate for additional development and further clinical investigation. Topical preparations seem especially promising, as do conditions that can respond to anti-inflammatory action and/or direct exposure, such as colon cancer prevention. Although the ultimate fate of resveratrol remains an open question, thus far, the compound has inspired innovative scientific concepts and enhanced public awareness of preventative health care.

• Journal of Korea Game Society
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• v.19 no.1
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• pp.109-120
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• 2019

This study analyzes how game play influences players' future happiness. Survey of 400 juveniles who attended G-star, a game show, was conducted to look into the influence of playing game with friends over players future happiness and their trust level towards others. The result suggests that playing game with friends and trust level towards others have positive influence on the future happiness level. In conclusion, playing game with friends has influence over players future happiness level with trust level towards others as a mediation variable.

• Safety and Health at Work
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• v.9 no.4
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• pp.421-426
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• 2018

Background: The purpose of this study was to investigate the effect of shift work on occupational safety in various industrial sectors. The study analyzes the effects of shift work on the health of workers by considering factors such as the workplace environment and welfare. Methods: Focusing on the $4^{th}$ Korean Working Conditions Survey, this study used an ordinary least-square multiple regression analysis. The dependent variable was the annual frequency of injuries reported by workers. Independent variables were categorized as demographic, shift work, workplace environment, and welfare variables. The analysis was conducted on two levels: 1) Shift work and nonshift work groups were compared, and 2) Shift work was compared with fixed and rotating shifts. Results: For the entire group, age, a low level of education, work hours, and daily and dispatch work negatively impacted the frequency of injuries. Shift work was negatively affected by workplace environment and welfare factors. In the shift group, the frequency of injuries was lower than that of regular workers, and the higher the autonomy in the choice of work hours, the lower the frequency of injuries. Furthermore, shift workers in Korea have more extended work hours (49.25 h/week) than other workers (46.34 h/week). Conclusion: Overall, welfare factors such as workplace satisfaction and worke-life balance reduced the frequency of injuries. The effect of shift work was limited, but it was confirmed that shift worker autonomy could reduce the frequency of injuries.

• Structural Engineering and Mechanics
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• v.70 no.3
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• pp.311-324
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• 2019

Long-span steel suspension bridges develop significant vibrations under the effect of external time-variable loadings because their slenderness. This causes significant stresses variations that could induce fatigue problems in critical components of the bridge. The research outcome presented in this paper includes a fatigue analysis of a long suspension bridge with 3300 meters central suspended span under wind action and train transit. Special focus is made on the counterintuitive interaction effects between train and wind loads in terms of fatigue damage accumulation in the hanger ropes. In fact the coupling of the two actions is shown to have positive effects for some hangers in terms of damage accumulation. Fatigue damage is evaluated using a linear accumulation model (Palmgren-Miner rule), analyses are carried out in time domain by a three-dimensional non-linear finite element model of the bridge. Rational explanation regarding the above-mentioned counterintuitive behavior is given on the basis of the stress time histories obtained for pertinent hangers under the effects of wind and train as acting separately or simultaneously. The interaction between wind and train traffic loads can be critical for a some hanger ropes therefore interaction phenomena within loads should be considered in the design.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.57.2-57.2
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• 2018

In astronomical observation, sequential device control and real-time data processing are important to maximize observing efficiency. We have developed series of automatic observing software (KAOS, KHU Automatic Observing Software), e.g. KAOS30 for the 30 inch telescope in the McDonald Observatory and KAOS76 for the 76 cm telescope in the KHAO. The series consist of four packages: the DAP (Data Acquisition Package) for CCD Camera control, the TCP (Telescope Control Package) for telescope control, the AFP (Auto Focus Package) for focusing, and the SMP (Script Mode Package) for automation of sequences. In this poster, we introduce KAOS10 which is being developed for controlling a small telescope such as aperture size of 10 cm. The hardware components are the QHY8pro CCD, the QHY5-II CMOS, the iOptron CEM 25 mount, and the Stellarvue SV102ED telescope. The devices are controlled on ASCOM Platform. In addition to the previous packages (DAP, SMP, TCP), KAOS10 has QLP (Quick Look Package) and astrometry function in the TCP. QHY8pro CCD has RGB Bayer matrix and the QLP transforms RGB images into BVR images in real-time. The TCP includes astrometry function which adjusts the telescope position by comparing the image with a star catalog. In the future, We expect KAOS10 be used on the research of transient objects such as a variable star.

• Asian Journal of Business Environment
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• v.11 no.1
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• pp.17-25
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• 2021

Purpose: This study extends previous empirical work on the threshold effects of institutions on the relationship between infrastructure and economic growth. It does so by using three sub-indices of institutions as the threshold variable in place of aggregate index. This is with a view to determining the roles of the sub-indices in the nexus between infrastructure and economic growth. Research design, data and methodology: The analysis is based on a dynamic panel threshold regression model using a panel data set comprising 41 countries in Sub-Saharan Africa over the sample period of 1996-2015. Data are obtained from Ogbaro (2019). Results: The study finds that infrastructure exerts significant positive effects on economic growth below and above the threshold values of the three sub-indices, with higher effects above the threshold values. Results also show that on average, the Sub-Saharan African countries are not able to satisfy any of the threshold conditions, which accounts for their poor growth experience. Conclusion: The study concludes that countries with weak institutions do not benefit maximally from infrastructure development policies. The paper, therefore, recommends that countries in Sub-Saharan Africa need to focus on improving their institutional patterns if they are to reap the optimum benefits from their infrastructure development efforts.

• The Journal of Economics, Marketing and Management
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• v.10 no.6
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• pp.47-57
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• 2022

Purpose: This study explored the relationship between product characteristics and customer purchase intention in cross-border online shopping. Research design, data, and methodology: Through literature review, the research model of product characteristics and consumers' purchase intention is constructed, and trust is taken as a medium variable. Based on the survey data of Chinese consumers, empirical analysis and hypothesis verification are conducted. This study used SPSS version 21 to confirm the reliability and validity of the research model. To confirm the media effect of the model in this study, the Sobel Test was used. Results: The results of hypothesis identification of this research model showed that 8 of the 11 hypotheses were adopted and 3 were rejected. Results confirmed the relationship between product characteristics (specification, diversity, reputation, novelty, quality) and customer purchase intention. Conclusions: The result from this study had particular theoretical significance for improving the research on cross-border online shopping systems to improve the safety and satisfaction of customers in cross-border online shopping.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.769-776
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• 2021

The focus of this study is to investigate the effect of earnings management and audit quality on the cost of equity capital and also examines whether audit quality acts as a moderating variable for the effect of earnings management on the cost of equity capital. The population in this study are companies from the consumer goods industry sector listed on the Indonesia Stock Exchange (IDX) during the 2016-2018 period. This sector was chosen because it is a sector that is able to survive in conditions of economic decline, so it becomes a good investment opportunity in the future. The sample selection was carried out using purposive sampling technique. By using the Moderated Regression Analysis (MRA) technique, the results show that earnings management has a positive effect on the cost of equity capital. Conversely, companies with good audit quality will bear lower cost of equity capital. The moderating hypothesis test results show that audit quality moderates the effect of earnings management on the cost of equity capital. This means that, even though the company carries out earnings management, investors have more confidence in the results of audits conducted by qualified auditors so that the cost of equity capital is low.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.145-150
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• 2021

The trend of globalization leads an increased need for international freight transportation and accelerates the development of the international logistics industry. The objective of this paper is to identify the critical factors that affect the choice of logistics service provider (LSP). The data sample was collected through a questionnaire, responded by 218 companies that outsource logistics services. The analysis uses descriptive statistics; exploratory factor analysis (EFA) and regression analysis were conducted with SPSS. The role of capabilities, customer service, and company reputation were evaluated and tested. Our findings show that capabilities and customer service have a considerable impact on the choice of LSP. The findings also indicate that company reputation do not have significant impact on the choice of LSP. They also showed that the capabilities is the variable that has the most significant effect on the choice of LSP. An implication of this study is that the competition should not only focus on pricing, but should be extended to improving enterprises capabilities, i.e., upgrading human resources, modernizing the modes of transportation, expanding business geographically and developing new technologies. Our study provides LSP managers with insights into how to meet customer expectations in the competitive logistics service sector.