• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2335-2347
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• 2023

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.22-32
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• 1997

This experiment was conducted to obtain information for the cultivation of Korean valerian(Valeriana lauriei var. dasycarpa Hara) which will be useful for medicinal and aromatic resources. The effect of different temperature conditions, light intensities and soil water conditions on growth, yield and component of essential oil of V. fauriei were measured at the Dankook University, Cheonan, and a study on the shading treatment was at Umsung, Chungchongbukdo, and Jinbu, Kangwondo, in 1995. V. laudei was planted at five different temperature conditions, 10, 15, 20, 25 and 3$0^{\circ}C$, eight light intensity conditions, 1, 000, 2, 500, 5, 000, 20, 000, 30, 000, 40, 000, 50, 000 and 60, 000lux, six soil water contents, 30, 45, 55, 70, 80 and 90％ of the saturated soil, during growth stage. Shading treatment was three conditions, 0, 25 and 50％, during the daytime in field conditions. Photosynthesis had a highly significant relationship with temperature conditions in a quadratic regression model, from which the temperature for the plant growth was estimated to be 17.7$^{\circ}C$. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was 20.3$^{\circ}C$. The content of essential oil and extract rate of root was the highest in the 15~2$0^{\circ}C$. Photosynthesis also was significantly affected by light intensity in a quadratic regression model, from which the optimum light intensity for the growth was estimated to be 40, 000lux. Root yield was more produced in Jinbu than that of in Umsung. The root yield was increased by the shading treatment in Umsung, whereas it was decreased by the shading treatment in Jinbu. The content of essential oil was not affected by the shading treatment of plants during the cultivation, while the compositions of components of essential oil were related to the growing locations. As soil water content was higher, the growth and content of root extract were increased. The optimum soil moisture for the growth of V. fauriei was 80~90％ of the saturated soil. In summary, the results indicated that the growth, yield and component of essential oil in V. fauriei were affected by environmental factors as well as soil moisture.

• Korean Journal of Culture and Social Issue
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• v.18 no.1
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• pp.127-152
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• 2012

The research investigates the attitudes toward children among mothers young children and maternal grandmothers, focusing specifically on the ideal number of children, gender preference, old age security and positive and negative values of children. A total of 442 respondents, consisting of 221 young mothers (average age of 35) and 221 maternal grandmothers (average age of 63) completed a questionnaire developed by Kim, Park and Kwon (2005). The reliability of the scales ranged from Cronbach α of .78 to .91. The results are as follows. First, as for the ideal number of children, young mothers reported that they would prefer two children, while grandmothers reported that they would prefer four children. As for the ideal number of male child, young mothers reported that they would prefer that they would prefer one son, while grandmothers reported two sons. Second, as for the gender of the child, young mothers did not show a gender preference, while grandmothers stated that at least one child should be a son, especially if it is the only child. Third, grandmothers had higher expectation of old age security in their male child than young mothers but two groups did not show any difference for the female child. Fourth, as for positive values of children, young mothers were more likely to emphasize personal aspects (i.e., psychological pleasure and happiness) and family cohesiveness, while grandmothers were more likely to emphasize social aspects (i.e., continuing the family line and old age security. As for negative values of children, young mothers were more likely to emphasize personal aspects (i.e., parental role and responsibility), while grandmothers were more likely to emphasize social aspects (i.e., family conflict and relationship). Fifth, as for factors that influenced the number of children that they decided to have, young mothers were more likely to report negative values of children (i.e., financial constraints), while grandmothers were more likely to emphasize positive values of children (i.e., continuing the family line).

• Korean Journal of Culture and Social Issue
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• v.23 no.2
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• pp.183-214
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• 2017

The purpose of this study was to examine the psychological characteristics of affecting never married men and women through analyzing the content of in-depth interviews about the idea of marriage and the reason for never married choice. For achieving this purpose, the in-depth interview was conducted with 9 men and women aged mid-20s to late 30s who said to choose never married life for a long time, and then the content of interview was analyzed using consensual qualitative research. As a result of analyzing the content of in-depth interview, it was derived into 2 areas, 10 sub-areas, and 25 categories. The results of the study were as follows. Firstly, it was found that research participants negatively recognized the marriage and had unrealistic expectation rather than no expectation for marriage. Secondly, most of the research participants felt negative feelings about their parents' patriarchal role, and they did not want to live like their parents. They also reported that they did not see their marriage separated from their parents. Thirdly, most of the research participants felt difficulty in forming relationships with intimate person, and it became more difficult to have expectations about spouses and marriage due to repeated relationship conflict patterns. Fourthly, the research participants showed psychological aspect of experiential avoidance and seeking for individuality in terms of never married choice. Most of the research participants predicted the failure of married life, and reported that they were trying to prevent uncomfortable feelings and sufferings by choosing never married life. Also they reported that individuality considered more important than connection with others(togetherness) and individual value considered more important than collective value. Participants in this study showed negative evaluation or had negative influences on the marriage life of parents and acquaintances. This is more likely to be a passive factor in never married choice, so future research should examine the characteristics of active factors in never married choice.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.702-713
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• 2023

Purpose: Depression is a prevalent mental health concern globally including South Korea. Given the growing interest in the relationship between diet and mental health, this study aimed to investigate the association between seafood consumption and depression among Korean adults. Methods: A cross-sectional analysis was conducted using data from the Korea National Health and Nutrition Examination Survey (KNHANES, 2014-2020). The study included 18,149 participants (7,541 men and 10,608 women) aged 19 years and older who completed the Patient Health Questionnaire (PHQ-9). Seafood intake levels were assessed using a oneday 24-hour dietary recall, and participants were categorized into three tertiles by gender. Depression status was determined using the PHQ-9 scores and the self-report of the doctor's diagnosis and treatment. Multivariable logistic regression analysis was performed to assess the association between seafood consumption and depression in both genders. Results: Participants with a higher seafood intake had a significantly lower nutritional density of total fat, while the nutritional density of omega-3 polyunsaturated fatty acids was significantly higher. The prevalence of depression was significantly lower in the highest tertile of seafood consumption compared to the lowest tertile in both men (p < 0.001) and women (p < 0.001). After adjusting for confounding factors, the highest tertile of seafood consumption demonstrated a decreased risk of depression compared to the lowest tertile in men (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.51-0.99; p-trend = 0.020) and women (OR, 0.73; 95% CI, 0.59-0.91; p-trend = 0.004). Conclusion: The findings of this study suggest that consuming seafood rich in omega-3 fatty acids may potentially reduce the risk of depression in the adult population.

• Journal of Venture Innovation
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• v.4 no.3
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• pp.141-150
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• 2021

Although management decisions centered on the board of directors and directors must be made in order to effectively promote ESG management, the company's management is not obligated to make decisions considering ESG factors. A Korean corporation(company) is an established organization for commercial or other profit, and the purpose of treating a legal organization as a corporation is to easily handle the legal relationship of a group (corporate's property) and individual property of a group member, but legal person such as rights to "harm public rights" or "defend fraud". Criminal liability for illegal acts of a corporation, but the liability of a corporation (natural person) for illegal acts of a corporation is recognized within a limited range, but the criminal liability of a corporation (natural person) is limited. As the social responsibility of a corporation is great, limiting the responsibility of a corporation-related person (natural person) to civil responsibility will halve its effectiveness if considering the impact on the corporation's national economy. Objective requirements such as the completeness of control, hybridization of property, infringement of creditors' rights, and small-capitalization, and the subjective intention of abusing the company system to avoid legal application to controlling shareholders should be denied. Despite the increasing influence on corporate society, such as large-scale projects and astronomical business profits, corporate officials (natural persons) are forced to be held liable for negligence and intentional liability within a limited range. In such cases, it is necessary to introduce criminal responsibility separately from civil responsibility to legal persons (natural persons) in consideration of the maturity of capitalism in Korean society and the economic status of the world. In Korea, the requirements for recognition of corporate denial are strict, but the United States says that it is sufficient to have control or fraud. Therefore, it is not about civil responsibility, but about criminal responsibility of a legal person (natural person), so if fraud is recognized, it can strengthen the corporate social responsibility.

• Journal of Venture Innovation
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• v.6 no.4
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• pp.99-111
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• 2023

This study aims to confirm that consumers' satisfaction with online shopping websites has changed to a phenomenon different from the past. In other words, in a situation where the use of e-commerce is expanding worldwide after the pandemic and various types of commerce such as mobile commerce and social commerce are formed, the consumer's information processing and decision-making process are meaningful in examining the behavior that has been changed based on the perceived motivation level of consumers by the new environment according to the consumption value and personal characteristics perceived by the consumer. In other words, the purpose of this study was to investigate the effect of consumption value and need for cognition on the satisfaction toward online websites as a mediating role in the trust of the website. As a result of testing Hypothesis 1, not only the hedonic value of the consumer for the website but also the utilitarian value had a positive influence on the satisfaction toward the website, and in particular, the utilitarian value showed a relatively greater influence than the hedonic value. However, the negative relationship between the need for cognition and satisfaction was found to be at a significant level under one-sided verification. In Hypothesis 2, only the utilitarian value among the consumption values of 2-1 showed a positive effect on satisfaction through a mediating role of trust. It was confirmed that the utilitarian value among the consumption values was an important factor in the satisfaction toward the website. The significance of this study is that, unlike previous research results, not only consumption value based on senses and emotions but also utilitarian value has a greater influence. Therefore, utilitarian value and need for cognition have a stronger influence on satisfaction if they play a mediating role based on the trust of the website used by consumers. These findings reflect the current market trend of online consumption, and they are helpful in the management and strategy of online websites based on consumer behavior understanding and major factors.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.453-460
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• 2023

This study was conducted to confirm the growth performance of Hanwoo steers according to the crude protein and calcium levels and their effects on carcass characteristics. The experiment consisted of a total of 4 groups: HPHC (CP 15%, Ca 1.2%), HPLC (CP 15%, Ca 0.6%), LPHC (CP 12.5%, Ca 1.2%), LPLC (CP 12.5%, Ca 0.6%). In the feeding trial, Hanwoo steers (650.8±16.27 kg, n = 32, 24 months of age) were divided into four feeding groups (n = 8 each) with the same initial body weight. Animals were fed with each rice straw and concentrate (1:9) until the late fattening stage. Growth performance was measured by daily weight gain, feed conversion rate, and final weight. Carcass characteristics were measured carcass weight, loin area, back-fat thickness and marbling score. There was no significant difference in growth performance and carcass characteristics among the treatment groups. However, the ratio of meat quality grade 1⁺ or higher was 76% in LPLC, which was higher than other treatments (HPHC, 63%; HPLC, 63% and LPHC, 50%). Therefore, reducing crude protein in the feed did not affect growth and carcass characteristics. In addition, calcium control in the late fattening stage did not affect growth performance. In LPLC, the ratio of meat quality 1⁺ or higher was the highest, so additional research on calcium control in feed is thought to be necessary. However, there was no significant difference in the relationship between protein and calcium levels in feed in all study results, so the influence of the two factors on each other is thought to be low.

• Journal of Korea Water Resources Association
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• v.56 no.11
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• pp.775-784
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• 2023

With the increasing trend of extreme rainfall that exceeds the design frequency of man-made structures due to extreme weather, it is necessary to review the safety of agricultural reservoirs designed in the past. However, there are no local government-managed reservoirs (13,685) that can be discharged in an emergency, except for reservoirs over a certain size under the jurisdiction of the Korea Rural Affairs Corporation. In this case, it is important to quickly deploy a mobile siphon to the site for preliminary discharge, and this study evaluated the applicability of a mobile siphon with a diameter of 200 mm, a minimum water level difference of 6 m, 420 (m²/h), and 10,000 (m²/day), which can perform both preliminary and emergency discharge functions, to the Yugum Reservoir in Gyeongju City. The test bed, Yugum Reservoir, is a facility that was completed in 1945 and has been in use for about 78 years. According to the hydrological stability analysis, the lowest height of the current dam crest section is 27.15 (EL.m), which is 0.29m lower than the reviewed flood level of 27.44 (EL.m), indicating that there is a possibility of lunar flow through the embankment, and the headroom is insufficient by 1.72 m, so it was reviewed as not securing hydrological safety. The water level-volume curve was arbitrarily derived because it was difficult to clearly establish the water level-flow relationship curve of the reservoir since the water level-flow measurement was not carried out regularly, and based on the derived curve, the algorithm for operating small and medium-sized old reservoirs was developed to consider the pre-discharge time, the amount of spillway discharge, and to predict the reservoir lunar flow time according to the flood volume by frequency, thereby securing evacuation time in advance and reducing the risk of collapse. Based on one row of 200 mm diameter mobile siphons, the optimal pre-discharge time to secure evacuation time (about 1 hour) while maintaining 80% of the upper limit water level (about 30,000 m²) during a 30-year flood was analyzed to be 12 hours earlier. If the pre-discharge technology utilizing siphons for small and medium-sized old reservoirs and the algorithm for reservoir operation are implemented in advance in case of abnormal weather and the decision-making of managers is supported, it is possible to secure the safety of residents in the risk area of reservoir collapse, resolve the anxiety of residents through the establishment of a support system for evacuating residents, and reduce risk factors by providing risk avoidance measures in the event of a reservoir risk situation.

• Korean Journal of Culture and Social Issue
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• v.15 no.2
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• pp.291-318
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• 2009

The purpose of this study was to find out the impact of psycho-social factors (social relationship and personal) as well as illness history and economic status on physical health and subjective well-being among the retired Koreans elderly. Data were collected from 1,315 elders (mean age = 72.70yrs) residing in Seoul and Chuncheon regional area via interviews(Time 1), and them were re-interviewed two year later(Time 2). Multiple regression analyses indicated that the retired elders' illness history, economic status, marital satisfaction, fulfillment of self-esteem need, drinking behavior, positive affectivity, negative affectivity and physical health to predict their subjective well-being at Time 1(R²=.705). The retired elders' economic status, marital satisfaction, positive affectivity, negative affectivity and physical health to predict their subjective well-being at Time 2(R²=.418). The retired elders' illness history, economic status, expectations for one's offspring, drinking behavior and subjective well-being to predict their physical health at Time 1(R²=.364). And the retired elders' illness history, economic status, marital satisfaction, positive affectivity and negative affectivity to predict their physical health at Time 2(R²=.265). In case of retired elderly, suggested for the psycho-social determenants of subjective well-being and physical health by occupational classification. The implications of this study and the suggestions for furture study were discussed.