• Journal of the Korean Wood Science and Technology
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• v.47 no.2
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• pp.129-144
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• 2019

This study aimed at developing an accelerated collection method that reduces measurement and collection time by improving and complementing the desiccator method, which is mainly used for quality control in wood-based panels and furniture production sites. First, this study measured the formaldehyde emissions from the wood-based panels by grade using the desiccator method. Further, this study compared the desiccator method with the developed process and analyzed the correlation in optimal temperature, time, and exposed area. The results showed that the developed process resulted in relatively similar outcomes in comparison to the desiccator method when the temperature was $100^{\circ}C$, the time was 1 h, and two specimens were used, at which the correlation was high. To verify the developed process, this study commissioned Korea Conformity Laboratories with the standardized temperature, time, and the number of specimens to compare them with the specimen that was not used in the actual test. As a result, the correlation to the desiccator method was shown to be very high. However, the formaldehyde emission measured by the accelerated collection process was mostly higher than that measured by the desiccator method. The formaldehyde emission grades from several specimens were one level higher. However, from the perspectives of quality control, it was determined that the accelerated collection method developed in this study could be sufficiently used.

• 재활복지
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• v.21 no.2
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• pp.113-137
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• 2017

In this study, we explore whether and how the experience of discrimination and social support affects physical health and mental health through disability identity among the disabled aged 50 and over. We also examine such relationship differs by the degree of disability. For the empirical test, we utilized the data from the Panel Survey for the Disabled conducted by our research team in 2016. According to structural equation model analysis, social support has a direct effect on disability identity. It also has a direct effect on physical health. As for the mental health, there are found direct effects of discrimination experience, social support, disability identity, and physical health, Furthermore, social support influences the mental health through disability identity. This finding suggests that social support for the disabled in old age increases disability identity and, in turn, it contributes their mental health. In the meanwhile, multiple group comparison analysis reveals the effect of discrimination experience on disability identity is found for those with lower level of disability but not for their counterparts. This seems to result from that the level of common ground which constitutes disability identity is low for the severely disabled. Thus, it requires our efforts to enhance disability identity focusing on common ground for the severe disabled.

• 재활복지
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• v.21 no.3
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• pp.65-84
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• 2017

This study identified predictors of intention to work among people with disabilities who maintain economic inactivity for two successive years by analyzing a total of 2,255 Participants in the 2014 data of the Panel Survey of Employment for the Disabled (PSED) with through $X^2$, t test, logistic regression. To explore factors affecting intention to work among people with disabilities who maintain economic inactivity, this study hypothesized the effectiveness of variables of demographic, disability, human resources, psycho-social factors based on previous studies. The analysis showed that male, spouse-being, low income status out of demographic variables were related to high probability of having intention to work among people with disabilities who maintain economic inactivity. In case of disability variables, experiencing disability-related discrimination significantly predicted the probability of having intention to work. However, the relationship between disability-related discrimination experiences and high intention to work needs to be viewed as correlated rather than cause-and-effect.In addition, literacy related to computer use/English proficiency/interpersonal and adaptation skills(human resources), experiences of vocational rehabilitation services (human resources), self-esteem (psycho-social) significantly predicted the probability of having intention to work among people with disabilities who maintained economic inactivity. Based on these results, support services for females with disabilities, effective rehabilitation programs of improving literacy related to computer use/English proficiency/interpersonal and adaptation skills and self-esteem, general expansion of vocational rehabilitation services for people with disabilities are suggested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.75-83
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• 2019

In order to fulfill the obligation to voluntarily reduce greenhouse gas emissions under the Paris Climate Agreement, the proportion of coal and nuclear power generation is reduced worldwide and national efforts are being made to spread renewable energy including solar power generation. Korea also intends to increase the proportion of renewable energy generation to 30~35% by 2040 by introducing laws and regulations. In addition, while the country is trying to apply solar power generation to sidewalks and roads, there is no research related to it in Korea. Therefore, as a precedent study to develop solar power generation roads, solar power generation concrete blocks applicable to sidewalks and plazas were developed and the applicability was evaluated by constructing them on the site. As a result of indoor experiment, compressive strength was measured by 25.5~35.7MPa and flexural strength was measured by 5.1~10.5MPa, which showed that all domestic standards were satisfied. However, the higher the unit cement amount, the lower the strength was measured according to the mixing of the broken fine aggregate. The absorption rate was 5.7%, which satisfied the domestic standard of 7% or less. As a result of the freeze-thawing test, the reduction rate of the compressive strength after 100 cycles was up to 6.3%. As a result of measuring the settlement amount after construction, the maximum of 2.498mm was measured and irregular settlement occurred in the overall area, which is because the resolution of the sand layer was poor during construction. Maintenance techniques of sidewalk concrete block and solar panel need to be established more efficiently through long-term operation in the further.

• Composites Research
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• v.32 no.5
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• pp.199-205
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• 2019

The composite material has the advantage that the fibers can be arranged in a desired direction and can be manufactured in one piece. However, micro voids can be formed due to micro air, moisture or improper curing temperature or pressure, which may cause the deterioration in mechanical strength. In this paper, the composite panels with different thicknesses were made by varying the curing pressure in an autoclave vacuum bag process and their microporosities were evaluated. Microporosity was measured by image analysis method, acid digestion method, and combustion method and their correlation with ultrasonic attenuation coefficient was analyzed. From the test results, it was found that the acid digestion method had the highest accuracy and the lower the curing pressure, the higher the microporosity and the ultrasonic attenuation coefficient. In addition, the microporosity and the ultrasonic attenuation coefficient were increased as the thickness of the composite panel was increased at the same curing pressure.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.3
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• pp.433-452
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• 2019

This study deals with shotcrete reinforcing performance according to the amount of synthetic fiber (PP fiber) and proper evaluation method. The shotcrete compressive strength, flexural strength and flexural toughness were tested by setting the mixing amounts of steel fiber ($37.0kg/m^3$) and synthetic fiber (PP fiber) as parameters ($5.0kg/m^3$, $7.0kg/m^3$ and $9.0kg/m^3$). Particularly, circular panel flexural toughness test (Road and Traffic Authority, RTA) was performed to evaluate the shotcrete energy absorption capacity. As a result, the compressive strength and the bending strength of the steel fiber reinforced shotcrete were large, but the flexural toughness of the synthetic fibe (PP fiber) reinforced shotcrete was large. Therefore, synthetic fiber (PP fiber) reinforced shotcrete is considered to have a reinforcing effect comparable to that of steel fiber reinforced shotcrete. Analysis of the relationship between the flexural toughness and the energy absorption capacity of synthetic fiber (PP fiber) reinforced shotcrete revealed that the energy absorbing ability is exhibited at a flexural toughness lower than the allowable standard (3.0 MPa). (Class A: 2.55 MPa = 202J, Class B: 2.72 MPa = 282J, Class C: 3.07 MPa = 403J). As a result of this study, it can be concluded that the actual shotcrete support performance can be evaluated by evaluating the support performance of the shotcrete measured at less than the allowable standard (3.0 MPa) at the actual tunnel site.

• Food Engineering Progress
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• v.21 no.3
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• pp.242-248
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• 2017

The acidity of soy curd fermented by lactic acid bacteria is a major factor degrading the sensory properties of soy curd. For preparation of soy curd with low sour taste, lactic acid bacteria were separated from kimchi. The lactic acid bacteria which showed yellow-clear zone around the colonies on BCP plate and formed soy curd with low level of acidity were selected. The selected strain was analyzed by 16S rDNA sequence and named as Pediococcus inopinatus Y2. The maximum viable cell number of the soy curd fermented by P. inopinatus Y2 was obtained at 10.73 log CFU/mL at $25^{\circ}C$ for 24 h of fermentation. By the results of panel test, the overall sensory quality of the soy curd produced by P. inopinatus Y2 was higher than that of Leuconostoc mesenteroides No. 4395 and Lactobacillus sakei strain No. 383.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.149-158
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• 2021

The aim of this study is to examine the relationships between high school student's self-efficacy and conversations with parents on career maturity. We consider how to instruct students in school life, efforts to increase students' career maturity and implications for career education in schools to evaluate students' school life. For the empirical analysis, the Korea Education and Employment Panel (KEEP II) survey data conducted in early 2018 was used. Study results found self-efficacy has a significant positive (+) effect on career maturity and a significant positive effect on conversations with parents. The frequency and content of conversation with parents have a significant positive (+) effect on career maturity. The effect of self-efficacy and conversations with parents variables on career maturity has a significant regulatory effect between the two groups who were satisfied with school life and those who were not.

• Journal of Navigation and Port Research
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• v.44 no.6
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• pp.541-549
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• 2020

This study conducts differential analysis on the financial positions of Korean shipping companies before and after the bankruptcy of the H carrier, looking specifically at their financial ratios, profit and loss patterns, and other factors related to their financial operation. Firstly, it was discovered that major measures of financial health, such as average assets per carrier, were not affected by the bankruptcy of the H carrier. However, despite this, most carriers experienced large changes in profits and losses, with total sales and shipping revenues averaging 424.5 billion won and 381.7 billion won respectively before the bankruptcy, but falling by half to 252.1 billion won and 234.6 billion won after the bankruptcy. Additionally, charter revenues and expenses also dropped by more than half. EBIT/sales and pre-tax revenue margins were also heavily affected after the bankruptcy, with both figures averaging 8% and 3% respectively before the bankruptcy, but falling into the negative range at -2% and -8% post-bankruptcy, resulting in significant deterioration in operational profitability. The study concludes that there is an urgent need to establish a global sales network, improve cost structures, and consistently secure stable cargo in order to increase Korean carriers' profitability. Of all financial measures, liquidity and total asset efficiency were identified as the most severely-impacted by the H carrier bankruptcy, thereby requiring the most pressing policy addressing.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.107-118
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• 2021

One of the debates regarding the college admission systems is about which admissions screening works as a mechanism for social mobility, between early and regular admissions. This study attempted to contribute to related discussions by analyzing the income level of college admissions students according to the admissions screening (early vs. regular admissions) using data from the third year survey of the Korean Education & Employment Panel II (KEEP II). Analyzing the dataset, we found that parental income was almost the same between students admitted from early and regular admissions. To be specific, average monthly parental income was 586.4 million Korean Won for students admitted from early admission while it was 585.4 million Korean Won for those admitted from regular admission, which means that the difference between the two was neither practically nor statistically significant. Applying the chi-square test, we tested whether the relationship between parental income and types of college admissions and found no statistical significance. Finally, categorizing colleges where students are admitted by ranking, we compared parental incomes among students. We found that parental income was higher for top-ranked universities, and that parental income was higher for students admitted from early admission. We concluded that early admission can possibly be an admission system for "well-offs" between the two, and that early admission may not be working as a pathway to facilitate social mobility compared to the regular admissions.