• Nuclear Engineering and Technology
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• v.16 no.3
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• pp.141-154
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• 1984

An analysis is presented of key phenomena and scenario which imply some general trends for beyond design-basis-accident in Kori-1 PWR dry containment. The study covers a wide range of severe accident sequences initiated by small break LOCA. The MARCH computer code, with KAERI modifications was used in this analysis. The major emphasis of the paper are two folds, 1) the phenomenologic understanding of severe accident and 2) a study of H2 combustion and debris/ water interactions in a specific small break LOCA for Kori-1 plant. The sensitivity studies for the specific plant data and thermal interaction modelings used in the SASA were performed. The results show that if hydrogen burning does occur at low concentration, the resulting peak pressure does not exceed the design value, while the lower concentration assumption results in repeated burning due to the continuing H$_2$ generation. For debris/water interaction, the particle size has no effect on the magnitude of peak pressure for the amount of water assumed to be in the reactor cavity. But, the occurrence of peak pressure is considerably delayed in case of using the dryout correlation. The peak containment pressure predicted from the hydrogen combustion and steam pressure spite during full core meltdown scenario does not present a severe threat to the containment integrity.

• Food Science and Preservation
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• v.14 no.2
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• pp.154-159
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• 2007

In efforts to use pine needle extract as a substitute for sugar, fermented pine needle extract syrup was added to the wheat flour nea in the manufacture of white bread The extract was added to levels of 8.3%, 11% and 18% of total weight based on the Brix degree of the dough The cohesion of each dough was checked, and the physical properties and storage stabilities of the baked breads were analyzed during storage at mom temperature. Analysis of the cohesion of each dough by farinogram showed that dough with pine needle extract was better than dough with sugar, in terms of both stability and durability of mixing. The pH of dough with syrup was steady during storage at pH 5.4 5.8, which is favorable for yeast activity. The dough with syrup also showed low firmness and good extensibility, both of which would favorably affect gas retention on fermentation. Increases in syrup addition resulted in higher product volumes. Bread with syrup was slow to increase in hardness during storage, suggesting that higher syrup concentrations inhibited development of staleness. The addition of syrup also inhibited the growth of aerobic bacteria and mold on the bread surface. The addition of syn did not cause any negative effect. The use of pine none extract syrup may thus contribute to improvements the physical properties, the storage stability, and the hygienic quality of bread.

• Journal of the Korean Society of School Health
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• v.24 no.2
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• pp.141-154
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• 2011

Purpose: The purpose is to provide basic information for establishing improvements on performance-based pay's evaluation method of health teachers. Methods: For subjects, 200 teachers at public elementary schools and 200 health teachers at public elementary schools in Gyeonggi-do were conveniently sampled, and then surveyed through a questionnaire. The questionnaire was to recognize recognition of teachers working under the teacher's performance-based pay system, which was quoted in the questionnaire of Choi ji-hye (2005) and Lee mi-gyeong (2008). Inquiry for the recognition of teachers on evaluation of health teacher's performance-based pay system and improvements on the performance-based pay's evaluation method of health teachers were used after consultation with five incumbent health teachers and a review with the thesis director. Results: The performance-based pay's evaluation method of health teachers has the same method with general teachers in schools, so it is not fair to evaluate the performance of health teachers. The ways to improve the performance-based pay evaluation method of health teachers is as follows: first, the approval on improving 'the number of class hours' which is a detailed item of a teacher's performance evaluation criterion to 'the number of health lesson hours per week and the number of students visiting the school infirmary per week'; second, improving 'life guidance' into 'counseling results of medically-treated students, parents of students and personal hygiene guidance'; third, improving 'a teacher in charge' into 'awarding of points by being recognized as a health teacher in charge of all students and considering the economic situation of the region,; forth, improving 'difficulty of position' into 'the number of health-teacher's annual promotion task items and the treatment number of issuing and receiving of official documents', and improving the 'task difficulty' into 'importance and urgency of emergency patient management, risk level and urgency of infectious diseases and avoiding work in charge' appeared to be more than 90% respectively. Conclusion: The performance-based pay system of teachers being carried out every year should be executed by preparing fair evaluation criteria suitable for task properties and the role of health teachers with different evaluation criteria compared to general teachers.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.73-85
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• 2021

The construction industry is considered to be a fatal accident industry, accounting for 28.5% of the total industrial accidents in 2017, as the number of industrial accidents in the construction industry has steadily increased over the past decade. So it is necessary to consider introducing Resilience Engineering, which is actively applied to risky industries around the world, to drastically reduce construction accidents. Although Resilience Engineering, which has emerged as the next-generation safety management centered on Hollnagel since the 2000s, claims the importance of strengthening Resilience abilities considering organizational structure and culture, most studies focus only on developing evaluation indicators. The purpose of this study is to analyze the impact of an organization's safety culture on its Resilience abilities in the construction industry. Specifically, it conducted empirical analysis on the impact of safety culture consisting of 'communication, leadership and safety systems' on the Resilience abilities(responding ability, monitoring ability, learning ability, anticipating ability), and the mediation relationship between leadership, communication, and safety system. The survey was conducted on construction workers, and an empirical analysis was conducted on the final 154 responses using SPSS 25 and Smart PLS 3. The results showed that the safety system had a significant impact on all Resilience Abilities, and communication had a significant impact on the remaining three except for anticipating ability among Resilience Abilities. On the other hand, leadership has been shown to have a significant impact on anticipating ability only. In the verifying of the mediation relationship between leadership, communication and safety systems, it was found that leadership affects all Resilience abilities by means of safety systems, but communication can only affect responding ability. This study has practical significance in that it suggests the need for policy-level efforts to introduce and apply Resilience Engineering and then expanded the effective safety management assessment of the construction industry in the future. Moreover, the academic implications are important in that the study attempted to expand the academic scope for a paradigm shift in the future as the safety culture has identified its impact on the Resilience abilities.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.147-154
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• 2021

Cutting management has been identified as a critical factor in the alfalfa production systems because it has a significant impact on maximizing yield and maintaining the forage quality. The objective of this experiment was to determine the proper cutting height according to harvesting time for optimizing nutrient yield and forage nutritive quality of alfalfa grown in alpine regions of Korea. Alfalfa was sown at a seeding rate of 30 kg/ha in August 2018 and harvested at four cuttings in 2019 (3 May, 2 July, 11 September, and 13 October). Cutting heights were adjusted at 5, 15, and 25 cm above the soil surface. Alfalfa plant was tallest at the third cutting (109 cm), which was on average 35 cm taller than the first or second cutting. Relative feed value (RFV) remained unaffected by cutting height at the first harvest, but increased consistently in subsequent harvests as cutting height increased. Alfalfa collected at the first and fourth cuttings had the highest RFV (mean 152), which was on average 8 and 67 units higher than the second and third harvests, respectively. At each harvest, in vitro dry matter digestibility was highest in alfalfa cut at a 25-cm height. Dry matter (DM) production at each cutting height was highest in the first cutting, accounting for on average 36-37% of total annual DM production, and lowest in the fourth harvest, accounting for about 11-13% of the total DM yield. The total dry matter production (in four harvests) was 4,218 kg/ha higher when alfalfa was subjected to a cutting height of 5 cm rather than 25 cm. Cutting height had no effect on total crude protein yield, but from the first to fourth cutting, the protein yield followed a decreasing trend. Finally, there were visible declines in forage nutritive quality when alfalfa was cut at a shorter height. However, the magnitude of difference in total forage yield may outweigh the slight decline in forage quality when alfalfa is cut at a lower height. The findings of this study could help the alfalfa growers make better harvest management decisions.

• Biomolecules & Therapeutics
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• v.29 no.3
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• pp.321-330
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• 2021

Oxidative stress plays a crucial role in the development of neuronal disorders including brain ischemic injury. Thioredoxin 1 (Trx1), a 12 kDa oxidoreductase, has anti-oxidant and anti-apoptotic functions in various cells. It has been highly implicated in brain ischemic injury. However, the protective mechanism of Trx1 against hippocampal neuronal cell death is not identified yet. Using a cell permeable Tat-Trx1 protein, protective mechanism of Trx1 against hydrogen peroxide-induced cell death was examined using HT-22 cells and an ischemic animal model. Transduced Tat-Trx1 markedly inhibited intracellular ROS levels, DNA fragmentation, and cell death in H2O2-treatment HT-22 cells. Tat-Trx1 also significantly inhibited phosphorylation of ASK1 and MAPKs in signaling pathways of HT-22 cells. In addition, Tat-Trx1 regulated expression levels of Akt, NF-κB, and apoptosis related proteins. In an ischemia animal model, Tat-Trx1 markedly protected hippocampal neuronal cell death and reduced astrocytes and microglia activation. These findings indicate that transduced Tat-Trx1 might be a potential therapeutic agent for treating ischemic injury.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.140-154
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• 2021

This study examines the structural relationship between parents' positive and negative parenting attitudes, life satisfaction, and academic helplessness. To this end, 2,595 middle school students (1,405 boys and 1,185 girls) were used among the KCYPS 2018 panel materials. The model was validated using a structural equation model, and the verification of the mediated effects of life satisfaction was significant with bootstraps. The results of the study are as follows. First, the positive and negative parenting attitudes of parents have a significant impact on life satisfaction. These results can be interpreted as having an impact on the lives of adolescent children, depending on their parenting attitudes. Second, the positive and negative parenting attitudes of parents have a significant impact on academic helplessness. These results can be interpreted as having an effect on the academic performance of adolescent children depending on their parenting attitudes. Third, satisfaction in life has a significant adverse effect on academic helplessness. These results can be interpreted as having a positive impact on studies according to the satisfaction level of youth's life, and having a negative impact on studies if life satisfaction is high and life satisfaction is low. Fourth, the satisfaction of life is mediated between parents' positive and negative parenting attitudes and academic helplessness. Through this study, it is meaningful in that it allows parents to understand the process of life satisfaction affecting their academic helplessness according to their parenting attitudes.

• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.148-154
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• 2021

Two specimens (1770~1850 mm disc width) of Mobula thurstoni, belonging to the family Myliobatidae, order Myliobatiformes, were first collected from the central coast of the Southern Sea of Korea in September 2018. This species is characterized by an anterior margin of disc with double curvature, a white-tipped dorsal fin, and the absence of a caudal spine. This species is morphologically similar to Mobula kuhlii, but has an anterior margin of pectoral fins with a double curvature and the dorsal coloration is bluish black rather than white. In addition, M. thurstoni was well distinguished from M. kuhlii as determined by mitochondrial DNA 16S rRNA sequences with genetic distances ranging from 0.030 to 0.069. The Korean name 'Mae-kkeun-kko-li-jwi-ga-o-li' is proposed for the species M. thurstoni.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.154-157
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• 2009

Pear has a gametophytic self-incompatibility (SI) system and its SI reaction is controlled by a single multi-allelic S-locus. 'Wonkyo Na-jasoojung 2' was selected from a cross between 'Wonwhang', early season major pear cultivar with high fruit quality and self-incompatible, and 92-18-79 (${S_4}^{sm}{S_4}^{sm}$) obtained from self cross of 'Osa-nijisseiki' (${S_2S_4}^{sm}$) (SM, stylar-part mutant), self-compatible bud mutant that originated from self-incompatible 'Nijisseiki' ($S_2S_4$) made in 2001 at the National Institute of Horticultural and Herbal Science, Rural Development Administration in Korea. '92-18-79' was selected as a self-compatible source through field investigation. It bloomed 1 day earlier than 'Osa-Nijisseiki' and similar to 'Wonwhang' in 2008. It is medium in tree vigor and spreading in tree habit. 'Wonkyo Na-jasoojung 2' is classified as highly susceptible to pear scab (Venturia nashicola) similar to 'Osa-Nijisseiki' and as resistant to black spot (Alternaria kikuchiana) similar to 'Wonwhang'. It had 65.7% fruiting rate by self pollination. The average optimum harvest time of 'Wonkyo Na-jasoojung 2' was 148 days after full bloom and it matured 2 days earlier than 'Osa-Nijisseiki' and 11 days later than 'Wonwhang'. The fruit is roundish oblate in shape and yellowish brown in skin color. Average fruit weight was 445 g and soluble solids content was 13.3 $^{\circ}Brix$. The flesh had abundant juice and negligible grit.

• Fire Science and Engineering
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• v.33 no.2
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• pp.145-154
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• 2019

The purpose of this study is to analyze the self-status of fire service personnel to identify their effect on self-efficacy and job satisfaction, and to improve the performance of their tasks in the field and perform their tasks efficiently. A survey of 177 current firefighters in the southern city of Gyeonggi Province conducted a correlation analysis and regression analysis through SPSS 22.0. The first study found that in relation to the self-status factor and the self-efficacy factor of firefighting services, the self-efficacy is rather high and the self-regulating effect is very high. Second, the effects of the self-status factor on the self-efficacy were significant in order of type Adult (A), type Free Child (FC), and type Adapted Child (AC). Third, analysis of correlation between self-status factors and job satisfaction factors showed inadequate correlation in all job satisfaction factors for Critical Parent (CP) types, and static correlation in all job satisfaction for Nurturing Parent (NP) types. Type Adapted Child (AC) was less satisfying to itself, to itself, to pay, to promote, to co-workers. Thus, the current strategic approach based on rationality needs to be strengthened by lowering the authority of the Critical Parent (CP) function in terms of self-status factors and enhancing the Adapted Child (AC) function in the lower satisfaction level of the parent.