• Journal of Advanced Marine Engineering and Technology
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• v.40 no.5
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• pp.397-402
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• 2016

This study presents the performance characteristics of a small Francis turbine with an inline casing and is a continuation of a previous study. A new runner design has been implemented using the previous facility. The specific speed of the new runner has been modified from $N_s$ 80 to $N_s$ $100m-kW-min^{-1}$. This turbine can be installed in a city water supply system. To dissipate excess pressures in the water line system an inline-turbine can be used instead of an inline-pressure reducing valve. Thus, some of the energy can be recovered by utilizing the pressure difference. For best applicability and minimal space consumption, the turbine is designed with an inline casing instead of a common spiral casing. As a characteristic of inline casing, the flow accesses to the runner are in the radial direction, showing low efficiency. The installation of vanes improves the internal flow and positively affects the output power. In contrast to the previous study, the new runner reduces the effect of the stay vanes by maintaining a higher efficiency.

• Journal of Distribution Science
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• v.17 no.8
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• pp.35-44
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• 2019

Purpose - This study examines the changes in the mobile MMORPG market in recent years and the factors affecting the performance of mobile games through flow experience according to the characteristics of game content. Research design, data, and methodology - This study focuses on the fact that the cause of game use behavior changes is the flow experience which influences the duration of mobile game continuation. The flow experience and the influencing factors are divided into the relationship between first, second-leading factors, and lagged factors. Results - The user's sense of challenge, skillfulness, concentration, and reality influenced the flow experience as a leading factor influencing the performance of MMORPG games. On the other hand, fun and preference were found to be the outcomes of the flow experience. This is because the game content is experienced not through passive enjoyment but by intentionally enjoying the game content. The flow experience has a positive effect on the intention of continuous use as in the previous study. Conclusions - This study found that the flow experience of game users is necessary for continuous use by organizing relationships of flow experience in mobile MMORPG users' gaming behavior.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.1
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• pp.43-51
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• 2015

This paper presents effect of aerodynamic loads on mooring line responses of a floating offshore wind turbine. A Matlab code based on blade element momentum (BEM) theory is developed to consider aerodynamic loads acting on NREL 5MW wind turbine. The aerodynamic loads are coupled with time-domain hydrodynamic analyses using one-way interaction scheme of the wave and wind loads. A semi-submersible floating platform which is from Offshore Code Comparison Collaborative Continuation(OC4) DeepCWind platform is used with catenary mooring lines simply composed of studless chain links. Average values of mooring peak tensions obtained from aerodynamic load consideration are significantly increased compared to those from simple wind drag force consideration. Consideration of aerodynamic loads also yield larger tension ranges which can be important factor to reduce fatigue life of the mooring lines.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.151-163
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• 2015

This study aims to clarify factors having effect on the turnover and entrepreneurial intention of financial institution workers. Particularly, this study analyzed the effect of job satisfaction, job insecurity, retirement expectation and retirement preparation activities. As research subjects, this study selected financial institution workers residing in Seoul and the capital area and used a total of 508 samples as analysis data. This study analyzed job satisfaction, job insecurity, retirement expectation and retirement preparation activities as factors having effect on the turnover and entrepreneurial intention of financial institution workers. The research results can be summarized as follows; Firstly, all the factors of job satisfaction had negative (-) effect on their turnover intention, and compensation satisfaction and interpersonal relation satisfaction also had negative (-) effect on their entrepreneurial intention. Secondly, since job insecurity had positive (+) effect on their turnover intention and entrepreneurial intentions, the more insecure their jobs became, the more their turnover and entrepreneurial intention increased. Thirdly, in the retirement expectation, forced frustration and continuation had positive (+) effect on their turnover intention, and forced frustration, new start and continuation also had positive (+) effect on their entrepreneurial intention. Fourthly, in the retirement preparation activity, entrepreneurial preparation, social preparation and physical preparation of retirement preparation activity had positive (+) effect on their turnover intention, but economical preparation had negative (-) effect on their turnover intention, while entrepreneurial preparation had positive (+) effect on their entrepreneurial intention. In other words, as they prepare business start-up more for retirement, their turnover and entrepreneurial intentions increase more. Although they receive higher wages than other workers in different job fields as financial institution workers, they showed significant results about turnover and entrepreneurial intentions, which indicates that job satisfaction, job insecurity, retirement expectation and preparation activities function as important variables in the relation with their turnover and entrepreneurial intentions. Such research results imply that it is necessary to develop various educational programs and turnover and business start-up support programs so that financial institution workers may have better understanding of both success and failure cases when they actually work on business start-ups.

• The Journal of the Convergence on Culture Technology
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• v.3 no.3
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• pp.1-6
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• 2017

In the case of book writing and publishing written by students, it has been implemented in the category of very few students. Even if it is limited to the minimum case, the detailed analysis of the effects will show that the education and learning effects are infinite, the maximum positive effect based on diversity and the effect of education and learning that can be extended to the continuation of sustainable capacity building. In this paper, I attempted to publish basic and intermediate major books on two occasions for first and second grade ordinary students majoring in IT. In addition to the basic satisfaction of education and learning, the book publishing performance of college student authors is excellent in various fields such as expansion of business based business, enlargement of major identity due to upward satisfaction, maximization of various late effects, securing sustainable development tendency. In the future, we plan to suggest ways to induce the general application of learning effect by conducting research that can achieve the same effect for middle and low level students.

• Journal of the Korean Applied Science and Technology
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• v.39 no.2
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• pp.233-245
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• 2022

The purpose of this study is to investigate the psychological well-being of Pilates class participants and their intention to continue exercising by examining the passion for leisure of Pilates participants who continue to exercise while taking risks during COVID-19 pandemic. The subjects were 285 Pilates participants. For data processing, SPSS 21.0 and AMOS 18.0 were used, and frequency analysis, reliability analysis, confirmatory factor analysis, and correlation analysis were conducted. In addition, path analysis was SEM and the bootstrapping method was used to examine the mediating effect of psychological well-being in the relationship between the passion for leisure and intention to continue exercising. First, passionate behavior had a positive effect on psychological well-being. Second, passionate behavior had a positive effect on exercise continuity. Third, psychological well-being had a positive effect on exercise continuity. Fourth, psychological well-being played a partial mediating role in the relationship between passionate behavior and exercise continuity.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.52.2-53
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• 2017

We develop a methodology to use the redshift dependence of the galaxy 2-point correlation function (2pCF) as a probe of cosmological parameters. The positions of galaxies in comoving Cartesian space varies under different cosmological parameter choices, inducing a redshift-dependent scaling in the galaxy distribution. This geometrical distortion can be observed as a redshift-dependent rescaling in the measured 2pCF. The shape of the 2pCF exhibits a significant redshift evolution when the galaxy sample is analyzed under a cosmology differing from the true, simulated one. Other contributions, including the gravitational growth of structure, galaxy bias, and the redshift space distortions, do not produce large redshift evolution in the shape. We show that one can make use of this geometrical distortion to constrain the values of cosmological parameters governing the expansion history of the universe. This method could be applicable to future large scale structure surveys, especially photometric surveys such as DES, LSST, to derive tight cosmological constraints. This work is a continuation of our previous works as a strategy to constrain cosmological parameters using redshift-invariant physical quantities.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.197-203
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• 1992

Studies of the pretreatment of chitin and its subsequent hydrolysis by Aspergillus carneus chitinase are reported. Ball milling was found to be the most effective way among the pretreatment methods tested. Data are presented describing the effect of enzyme and substrate concentrations on the rate and extent of the hydrolysis process. It was found that the successive addition of enzyme improved the saccharification yield. Significant product inhibition of the chitinase was observed when N-acetylglucosamine concentration was 3.6％ or higher. Adsorption of enzymes to the substrate occurred during a 24 hr hydrolysis period. An initial rapid and extensive adsorption occurred, followed by gradual desorption which increased during the time of reaction. Intermediate removal of the hydrolyzate and continuation of the hydrolysis by adsorbed enzyme on the residual chitin was also investigated. A total of 75.4 g/l reducing sugars, corresponding to 69.2％ saccharificaton yield (as N-acetylglucosamine) was obtained. In addition an increase in the amount of recoverable enzymes was observed under these conditions. Evidence presented here suggests that the technique, whereby the free enzymes in the recovered hydrolyzate are re-adsorbed onto the new substrate, may provide a means of recirculating the dissolved enzymes.

• Journal of Veterinary Clinics
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• v.4 no.2
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• pp.463-472
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• 1987

Although there are many reports on the bovine electroacupuncture anesthesia, its application to clinical cases needs much to be verified. In order to apply the electroacupuncture anesthesia to bovine species, a new anesthesia technique, which is safe and effective, must be developed. In the present study, 11 meridian points were selected and 11 kinds of meridian points were prescribed to develop an effective and safe electroacupucture methods in the bovine species. The results obtained are summarized as fellows : 1. When the maximun electric current (30Hz at 5.3-5.6V ) was applied, anesthesia was attained with the signs of tetany and tremor : When the electric current was continued for 15-20 minutes, the signs of tetany and tremor diminished markedly. 2. If the electric current was adjusted to 30Hz at 3.5-4.0V and continued, the tetany and tremor disappeared. The skin was slackened, thus suitable for surgical operation. The continuation of anesthesia could be regulated at operator's own will. 3. The same anesthesia effect could be attained by using any one meridian point when the points were symmetrical. 4. Transient changes of clinical signs and blood pictures were noted during the stages of acupuncture anesthesia. However, the red blood cell counts, white blood cell counts and hematocrit values were always within the normal range.

• Journal of the Korean Data and Information Science Society
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• v.11 no.2
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• pp.157-172
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• 2000

Metal containers represent a situation where a specific metal is exposed to a wide variety of electrolytes of varying degrees of corrosivity. For example, hundreds, if not thousands of different products are packaged in an aluminum beverage can. These products vary in pH, chloride concentration and other natural or artificial ingredients which can effect the type and severity of potential corrosion. Both localized (perforation) and uniform corrosion (metal dissolution without the onset of pitting) may occur in the can. A quick test or series of tests which could predict the propensity towards both types of corrosion would be useful to the manufacturer. Electrochemical noise data is used to detect the onset and continuation of pitting corrosion. Specific noise parameters such as the noise resistance (the potential noise divided by the current noise) have been used to both detect pitting corrosion and also to estimate the pitting severity. The utility of noise resistance and other electrochemical parameters has been explored through the application of artificial neural networks. The versatility of artificial neural networks is further demonstrated by combing electrochemical data with electrolyte properties such as pH and chloride concentration to predict both the severity of both localized and uniform corrosion.