• KSBB Journal
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• v.8 no.2
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• pp.164-171
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• 1993

The production of extracellular polysaccharide by Methylomonas mucosa (NRRL B-5696) was investigated. The microorganism uses methanol as the carbon source for their growth and produces exopolysaccharides. The productivity of exopolysaccharides was investigated under various culture modes: batch, fed-batch and continuous culture. In flask culture the growth of cell mass and the production of polysaccharide were inhibited at above 1% (v/v) methanol. At 1%(v/v) methanol maximum specific growth rate was obtained. As C/N ratio (g methanol/g ammonium sulfate) increased, polysaccharide production increased and cells mass decreased. Magnesium ion was also found to be essential for the polysaccharide production. In batch culture the production of polysaccharides was more affected by the specific growth rate than the cell concentration. In fed-batch culture the concentration of polysaccharide was 4 times higher than that of batch culture, but the yield was lower. The productivity of fed-batch with continuous feeding was higher than that of batch or fed-batch with intermittent feeding. This is due to no methanol limitation or inhibition that used to occur in fed-batch culture with intermittent feeding. In continuous culture pure oxygen was supplied to avoid the oxygen limitation. As the dilution rate in- creased up to 0.21 h-1, the yield and productivity increased. The solution viscosity of the produced polysaccharide obtained from above increased exponentially with the concentration of polysaccharide.

• Journal of Information Management
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• v.39 no.4
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• pp.97-120
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• 2008

Evaluation indicators reflecting recent digital environments are needed as a tool to increase research library's competitiveness and productivity. Especially, research libraries have different subject backgrounds and there are many one-person libraries. In this study, we developed new evaluation indicators based on the draft indicators made in 2007 considering these environmental elements so that it may be used easily and applicable to various research libraries. In developing the new indicators, we reviewed other library type's indicators and listened carefully to the comments from expert librarians in the research libraries through several meetings. After developing the indicators, we made a survey in order to verify its validity as well as its effectiveness and also made a test evaluation for research libraries. The proposed indicators will contribute in evaluating the current level of Korean research libraries and promoting them to the future-oriented libraries.

• Journal of the Korean Society for Railway
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• v.14 no.1
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• pp.57-65
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• 2011

The estimation of traffic safety and passenger comfort when the train is running on the bridge is a estimation unique to the railway bridge. The standards for such estimation are included in the Eurocode, the Shinkansen design criteria, and the design guideline of the Honam High-speed railway. The items are bridge responses including vertical displacement of bridge, vertical acceleration, and slab twist. In principle, a direct estimation based on the train responses has to take place. However, the estimation based on the bridge responses can be seen as an indirect estimation procedure for the convenience of the bridge designer. First, it is general practice that traffic safety can be verified as a derailment coefficient or wheel load decrement The general method of estimating passenger comfort is to calculate the acceleration within the train car-body. Various international indexes have been presented for this method. In the present study, traffic safety and passenger comforts are estimated directly by bridge/train interaction analysis. The acceleration and wheel load decrement are obtained for the estimation of traffic safety and passenger comforts of a suspension bridge which has main span length of 300m. Also, the consideration of seismic load with simultaneous action of moving train is done for bridge/train/earthquake interaction analysis.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.201-205
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• 2008

'Morningpurple' is a new sweetpotato variety developed by Mokpo Experiment Station, National Institute of Crop Science (NICS), RDA in 2007, for flowering. This variety was selected from the cross between Sinchunmi and Hi-dry in 2004, seedling and line selections were practiced from 2005 to 2006. 'Morningpurple' has morning glory type flowers with purple color. It has triangular leaf, green with purple vine and petiole, elliptic storage root, red skin and yellow flesh color of storage root. The average yield of storage root was 15.0 ton/ha. Number of storage roots over 50 gram per plant was 2.6, and the average weight of storage root was 143 gram.

• Women's Health Nursing
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• v.25 no.2
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• pp.169-181
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• 2019

Purpose: To determine association of contraceptive knowledge, sexual double standard, and contraceptive self-efficacy among unmarried women in their 30s and 40s. Methods: With a survey design, data were collected from 119 unmarried women in their 30s and 40s in G city of Korea from September 2017 to March 2018. Data were analyzed by descriptive statistics, independent t-test, one-way ANOVA, $Scheff{\acute{e}}$ test, Pearson's correlation coefficients, and stepwise multiple regression. Results: Contraceptive knowledge, sexual double standard, and contraceptive self-efficacy scores of participants were $8.97{\pm}2.22$, $18.54{\pm}5.57$, and $45.84{\pm}6.90$, respectively. Contraceptive self-efficacy was negatively correlated with sexual double standard. Factors influencing contraceptive self-efficacy were sexual double standard (${\beta}=-.26$, p=.003), existence of boyfriend (${\beta}=.25$, p=.004), and contraceptive education need for adults (${\beta}=.17$, p=.044). They explained 19% of contraceptive self-efficacy of participants. Conclusion: To increase contraceptive self-efficacy of unmarried women in their 30s and 40s, lowering sexual double standard and developing customized contraceptive education according to age and knowledge level are needed. Research on factors related to contraceptive self-efficacy of unmarried women in their 30s and 40s from various regions are also needed in the future.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.269-276
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• 2021

The purpose of this study is to investigate the relationship between always being on call and the conflict factors between work and life balance among employees' in the IT relative industry. The results are as follows: always being on call factor perceived by employees' in the IT relative industry influences to conflict factor between work and life balance. Moreover, always being on call factor negatively effects on all factors of job insecurity which are impotent feeling and possibility of job loss. From the analysis of relation between job insecurity and conflict between life and work balance showed that the factor of impotent feeling influence on conflict between life and work balance while the factor of job loss does not. In addition, job insecurity(impotent feeling and possibility of job loss) partially mediated between always being on call and the conflict factors between work and life balance among employees' in the IT relative industry.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.221-226
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• 2022

The purpose of this study is to explore the differentiated motivations of users of live commerce by focusing on the entry into untact consumption culture. In addition, we intend to verify the mediating effect of engagement in the relationship between the motivation and attitude of live commerce use. As for the research method, an online survey was conducted targeting live commerce users, and 245 valid samples were used for analysis. For data analysis, frequency analysis, exploratory factor analysis, reliability analysis, multiple regression analysis, and mediation regression analysis were performed. As a result of the analysis, the motivation for using live commerce was derived from four factors: Enjoyment of interaction, Substitutability of personal examination, Need for community, Trend setting. And Engagement was found to have a significant effect on attitude. Finally, engagement was found to have a partial mediating effect in the relationship between the motivation and attitude of live commerce use. The research results will provide implications for understanding non-face-to-face consumption culture and establishing effective strategies for the live commerce industry in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.250-265
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• 2022

Positive effects such as significantly reducing traffic accidents caused by human error can be expected by the introduction of Automated vehicles (AV). However, as new traffic safety issues are expected to occur in the future due to errors in H/W or S/W of autonomous vehicles and lack of its function, it is necessary to establish a scenario to evaluate the driving safety of AV. Therefore, in this study, functional scenario was developed to evaluate the driving safety of AV based on traffic accident data of the National Police Agency. Using the GIS program, QGIS, traffic accident data that occurred in the toll gate and ramp sections of expressway were extracted and accident summary items were checked to classify the types of accident. In addition, based on the results of accident type classification, functional scenario were developed that contains various dangerous situations in the tollgate and ramp sections.

• Science of Emotion and Sensibility
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• v.22 no.1
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• pp.35-44
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• 2019

Individuals with problematic hypersexual behavior (PHB) evince the inability to control sexual impulses and arousal. Previous studies have identified that these characteristics are related to structural and functional changes in the brain region responsible for inhibitory functions. However, very little research has been conducted on the functional connectivity of these brain areas during the resting state in individuals with PHB. Therefore, this study used functional magnetic resonance imaging devices with the intention of identifying the deficit of the functional connectivity in the executive control network in individuals with PHB during the resting state. Magnetic resonance imaging data were obtained for 16 individuals with PHB and 19 normal controls with similar demographic characteristics. The areas related to the executive control network (LECN, RECN) were selected as the region of interest, and the correlation coefficient with time series signals between these areas was measured to identify the functional connectivity. Between groups analysis was also used. The results revealed a significant difference in the strength of the functional connectivity of the executive control network between the two groups. In other words, decreased functional connectivity was found between the superior/middle frontal gyrus and the caudate, and between the superior/middle frontal gyrus and the superior parietal gyrus/angular gyrus in individuals with PHB. In addition, these functional Connectivities related to the severity of hypersexual behavior. The findings of this study suggest that the inability to control sexual impulses and arousal in individuals with PHB might be related to the reduced functional connectivity of executive control circuits.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.155-177
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• 2012

This paper aims at measuring the changes of Malmquist productivity and technical efficiency of Korean shipbuilding Industry and examinig their determinants utilizing the panel analysis. The increase of the technological progress was greater than technical efficiency, resulting in the increase of the total factor productivity for the period of 2004-2010. This study also employs the panel technique to analyse the effects of Employee, Dock, and Length on the changes of Malmquist productivity and technical efficiency. The dependent variables are obtained from three combinations, which are (Employee, Dock, and CGT), (Employee, Length, and CGT), and (Dock, and Length, and CGT). The empirical results show that all of the explanatory variables have a positive effect on the change of Malmquist productivity and technical efficiency.