• Explosives and Blasting
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• v.38 no.4
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• pp.26-36
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• 2020

With the increase of expansion and use of the underground space, the possibility of an underground explosion by terrorists is increasing. In this study, after modeling a circular tunnel excavated at a depth of 50m, an explosion load was applied to the inside of the tunnel. As for the explosion load, the explosion load of the maximum explosive amount for six types of vehicle booms proposed by ATF (Bureau of Alcohol, Tobacco, and Firearms) was calculated. For the rock mass around the circular tunnel, three types of rock grades were selected according to the support pattern suggested in the domestic tunnel design. Nonlinear dynamic analysis was performed to evaluate the influence of the ground structure by examining the surface displacement using the explosion load and rock mass characteristics as parameters. As a result of the analysis, for grade 1 rock, the influence on the uplift of the surface should be considered, and for grade 2 and 3 rocks, the influence on a differential settlement should be considered. In particular, for grade 3 rocks, detailed analysis is required for ground-structure interaction within 40m. Also, it is considered that the influence of Young's modulus is the main factor for the surface displacement.

• Fashion & Textile Research Journal
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• v.25 no.5
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• pp.578-592
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• 2023

This study identified and evaluated by deriving and categorizing concepts related to the user experience of metaverse fashion shows using grounded theory, which is a qualitative research method. Based on experiential marketing theory, in-depth interviews were conducted for 14 days with 14 males and females in their 20s and 30s. The research results and contents are as follows: The causal condition was the purpose of using metaverse fashion shows, and the action/interaction strategy caused by such a case was found to be establishing a system for metaverse fashion shows and promoting a positive brand image. The results included content evaluation of satisfaction, normal, or dissatisfaction. The contextual condition was a change in the form of consumption that emphasized experience, while the interventional condition was psychological distance. Based on this, the core category was defined as "consumption patterns that emphasized the purpose of use and experience affects the metaverse fashion shows and psychological distance appeared as a user experience evaluation through the establishment of a system of metaverse fashion shows and the promotion of a positive brand image". User types were classified as active or passive. Active users have the autonomy to select content according to their individual preferences, and accordingly, their experience preference tends to change. In contrast, passive users' preference for the technical quality of content is relatively low, but they have a high concentration of content diversity and audio-visual interest elements.

• The Journal of the Korea Contents Association
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• v.8 no.12
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• pp.366-374
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• 2008

The purpose of this study was to analyze pre-service elementary school teacher's enjoyment factors experienced in PE classes. In order to achieve the purpose of this study, 30 students attending in G University of Education were selected in this study and data were collected through open-ended questionnaire and in-depth interviews. As a result of the analysis, this study have classified the enjoyment factors of pre-service teachers in PE classes. First, happiness of achievement through physical activity Second, inspiration of self-confidence through praise Third, variety of program presentation for arouse interesting Fourth, desire expression to aggressive physical activity Fifth, personal relationship of PE teacher Sixth, enjoyment of community spirit and interaction.

• Korean Journal of Social Welfare
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• v.62 no.4
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• pp.223-248
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• 2010

This study is to explore the contents and interaction of residents voluntary network and propose the strategies to promote residents voluntary network. The grounded theory was utilized to attain our object. Total of seven social worker and 17 residents participated in the study. Data were collected through in-depth interviews and documents. The data were analyzed by using Strauss and Corbin's method. Results are the followings. In open coding 13 categories, 32 subcategories and 133 concepts were constructed. In axial coding causal conditions were qualitative ascent of needs, emergence of the right welfare consumer. Phenomenon was agitation of praxis ground and grope of exist. Contextual conditions were crisis resources, skepticism of welfare. Intervention conditions were maturation of welfare cognition and proliferation of the sense of community responsibility. Strategy were resocialization of voluntary organization and construction of field related service delivery system. Consequence were grass routing welfare strategic fitting service system. In selective coding we constructed the core category: The praxis revolution from bottom for break social welfare environment.

• The Journal of the Korea Contents Association
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• v.7 no.3
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• pp.68-78
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• 2007

In a virtual aquarium, the behavior of fish objects is the most important factor in respect of visual effects. In addition to the individual behavior of fish object, the interactions between objects due to their attributes, can improve the dynamics and reality of the virtual world. In this paper, we analyze the principal habits of fish objects such as the vitality, the range of movement, the maximum depth of water they can live, and the cycle of eating. Then, we suggest a method for simulating the stable marine ecosystem with controlling the behaviors, the interaction with other species, the average span of life, and all that sort of thing based on the result of analysis. Because we can freely modify the behavior of fish object by altering the values of attributes, it can be utilized in the dynamic virtual aquarium, the 3D aquarium screen saver, and the virtual fish game, and so on.

• Journal of the Korea Institute of Building Construction
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• v.17 no.3
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• pp.235-243
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• 2017

Carbonation of concrete is being occurred due to interaction of atmospheric carbon dioxide with hydroxides. Reinforce concrete (RC) structure is getting collapse or accident due to corrosion of embedded steel rebar. The maintenance of reinforced concrete structure recently has the attention of researchers regarding durability of structure and its importance day by day is increasing. In order to study the carbonation progress of pre-repaired concrete, present study was carried out to measure the carbonation velocity for different repair materials up to 100% of carbonation. The obtained results have predicted the carbonation progress of repair materials in service condition. These results have been verified by FEM and FDM analysis. As a result, the carbonation depth can be predicted by using the carbonation prediction formula after the repair, and the analytical and the experimental values are almost similar when the initial $Ca(OH)_2$ concentration is assumed to be 40%.

• Geomechanics and Engineering
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• v.13 no.5
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• pp.715-742
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• 2017

Earth berms are often left in place to support retaining walls or piles in order to eliminate horizontal struts in excavations of soft soil areas. However, if the excavation depth is relatively large, an earth berm-supported retaining system may not be applicable and could be replaced by a multi-bench retaining system. However, studies on multi-bench retaining systems are limited. The goal of this investigation is to study the deformation characteristics, internal forces and interaction mechanisms of the retaining structures in a multi-bench retaining system and the failure modes of this retaining system. Therefore, a series of model tests of a two-bench retaining system was designed and conducted, and corresponding finite difference simulations were developed to back-analyze the model tests and for further analysis. The tests and numerical results show that the distance between the two rows of retaining piles (bench width) and their embedded lengths can significantly influence the relative movement between the piles; this relative movement determines the horizontal stress distribution in the soil between the two rows of piles (i.e., the bench zone) and thus determines the bending moments in the retaining piles. As the bench width increases, the deformations and bending moments in the retaining piles decrease, while the excavation stability increases. If the second retaining piles are longer than a certain length, they will experience a larger bending moment than the first retaining piles and become the primary retaining structure. In addition, for varying bench widths, the slip surface formation differs, and the failure modes of two-bench retained excavations can be divided into three types: integrated failure, interactive failure and disconnected failure.

• Journal of Korean Academy of Nursing
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• v.51 no.3
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• pp.320-333
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• 2021

Purpose: The study was conducted to explore the experiences of job retention among working people with mental illness. Methods: The participants were members with mental illness at the S Community Mental Health Center in Gyeonggi Province and who had been working for more than six months. The data were collected through in-depth interviews with 11 participants between June 27 and August 20, 2018. The data were analyzed through Corbin and Strauss's grounded theory method. Results: The core category was struggling to take root in the community as a productive member. The core phenomenon was the desire to be a productive person, and the causal condition was the willingness to change for a purposeful life. The action and interaction strategies included maintaining regular living patterns, maintaining medication, developing one's tips for self-management, and self-approval. The intervening conditions were difficulties in forming social relationships, presence of symptoms, social resources, and acceptance of one's mental illness. The consequences were restoration of family relationships, healthy pleasure through work, social inclusion, development of self-worth, and transition to an independent person. Conclusion: Working people with mental illness are struggling to take root in the community as a productive member. This study suggests that a holistic understanding of the job retention experience among people with mental illness is required. The findings will provide the basis for developing interventions that can improve job retention among working people with mental illness.

• Animal Bioscience
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• v.35 no.3
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• pp.434-443
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• 2022

Objective: The study was conducted to investigate the impact of boron supplementation on nutrient digestibility, inflammatory responses, blood metabolites and diarrhea index, and their relevance to growth performance in weaned pigs housed in good and poor sanitary environments for 14 days after weaning. Methods: A total of 108 male pigs (Duroc×[Yorkshire×Landrace]) weaned at 21 days of age were used in a randomized complete block design with 2×3 factorial arrangement. Pigs were assigned to three boron treatments (0, 5, and 10 mg/kg) under two environments (good and poor sanitary) to give six replicates per treatment (3 pigs per replicate). On 0, 7, and 14 days, one pig per replicate was euthanized to collect, ileum tissue samples, and rectal fecal samples. Results: Boron supplementation quadratically influenced (p<0.001) feed intake and weight gain in pigs housed in good sanitary conditions from 1 to 14 days post-weaning where pigs offered 5 mg/kg boron optimized weight gain and feed intake. There is a quadratic interaction (p = 0.019) on feed intake for 1 to 14 days post-weaning where 5 mg/kg boron increased feed intake in good sanitary conditions. Pigs housed in the poor sanitary environment decreased (p<0.001) villus height and crypt depth in ileum at days 7 and 14. On day 7 and 14, crude protein digestibility was quadratically influenced (p<0.05) by boron supplementation. Boron supplementation linearly increased (p<0.05) plasma calcium and cholesterol levels whilst linearly (p = 0.005) reducing plasma triglyceride concentrations. Diarrhea index was quadratically influenced (p<0.05) by boron supplementations regardless of sanitary conditions where 5 mg/kg boron inclusion achieved the lowest diarrhea index. Conclusion: Pigs offered 5 mg/kg of boron increased weight gain which may be deduced by improved dry matter, crude protein, and energy digestibility regardless of the sanitary conditions.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.153-153
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• 2021

Storm Storm event is one of major issues in South Korea due to devastating damage at its landfall. A series of statistical study on the historical typhoon records consistently insist that the typhoon translation speed (TS) is on slowdown trend annually, and thus provides an urgent topic in assessing the extreme storm surge under future climate change. Even though TS has been regarded as a principal contributor in storm surge dynamics, only a few studies have considered its impact on the storm surge. The landfall angle (LA), another key physical factor of storm surge also needs to be further investigated along with TS. This study aims to elucidate the interaction mechanism among TS, LA, coastal geometry, and storm surge synthetically by performing a series of simulations on the idealized geometries using Delft3D FM. In the simulation, various typhoons are set up according to different combinations of TS and LA, while their trajectories are assumed to be straight with the constant wind speed and the central pressure. Then, typhoons are subjected to make landfall over a set of idealized geometries that have different depth profiles and layouts (i.e., open coasts or bays). The simulation results show that: (i) For the open coasts, the maximum surge height (MSH) increases with increasing TS. (ii) For the constant bed level, a typhoon normal to the coastline resulted in peak MSH due to the lowest effect of the coastal wave. (iii) For the continental shelf with different widths, the slow-moving typhoon will generate the peak MSH around a small LA as the shelf width becomes narrow. (iv) For the bay, MSH enlarges with the ratio of L/E (the length of main-bay axis /gate size) dropping, while the greatest MSH is at L/E=1. These findings suggest that a fast-moving typhoon perpendicular to the coastline over a broad continental shelf will likely generate the extreme storm surge hazard in the future, as well as the slow-moving typhoon will make an acute landfall over a narrow continental shelf.