• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.5
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• pp.671-679
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• 2022

Harmful factors such as shock waves and fragments are generated at domestic ammunition testing sites and military shell shooting training sites due to frequent shooting and explosion tests. As a result, complaints from local residents are rapidly increasing, and there is a high risk of damage to facilities and human life. The recently constructed ammunition test site built a test facility for firing artillery and rocket propulsion in a narrow area with a radius of 300 m due to site restrictions, but damage to the facility is accumulating because there is no adequate protective structure. Therefore, in this study, quantitative data on harmful factors such as noise, vibration, shock wave, and thermal effect generated between artillery firing and rocket propulsion tests were measured, and explosion pressure characteristics were analyzed to design a protective structure, and use Autodyn to protect performance. to perform verification.

• Journal of Conservation Science
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• v.32 no.3
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• pp.365-375
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• 2016

This study was interpreted the forming process of surface contaminants on ten-story stone pagoda of Wongaksa temple, Seoul. Results of research, we estimated that black contaminants were formed by graphite stuck carbon in air pollution substance after that gypsum was generated by chemical weathering on stone pagoda. White contaminants were built by recrystallization of calcite that were made by decomposition of finishing materials and structure on the stone surface. To preserve a long-term of stone pagoda in Wongaksa temple, there were required that continuous monitoring, anticorrosion treatment and contaminants cleaning of protective facilities.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.129-135
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• 2020

The purpose of this research is to analyze the gamma ray shielding effect of heavy concrete containing magnetic aggregate and to confirm the applicability to the military protective facilities. In general, a military concrete structure protects combatants from bullets, and also it provides some radiation shielding. In this research, experiments were conducted using a Cs-137 source to check the gamma ray shielding effect. In addition, the Monte Carlo N-Particle(MCNP) modeling was applied to evaluate the gamma ray shielding effect of a military structure. As a result, as the concrete thickness increased, the shielding performance improved according th the linear attenuation law. With that, as the ratio of magnetic aggregate was increased, gamma ray shielding performance was also improved. Therefore, this research verified that the application of magnetic aggregate concrete to military facilities for radiation shielding purposes would be useful.

• Korean Journal of Occupational Health Nursing
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• v.24 no.4
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• pp.352-362
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• 2015

Purpose: The purpose of this study was to investigate the effects of job stress and support from supervisors on depression of care givers in elderly care facilities. Methods: Subjects were 191 care givers working in elderly care facilities in K-Province in Korea. Data were collected from self-administered questionnaires. Descriptive statistics, ${\chi}^2$ test, t-test, F-test, Pearson's and Spearman's correlation coefficients, and hierarchical multiple logistic regression with dummy variables were used for statistical analysis of data. Results: Job stress measured with Korean Occupational Stress Scale was $56.16{\pm}5.88$. Emotional and instrumental support from supervisors were $37.05{\pm}7.30$ and $32.39{\pm}7.34$, respectively. After controlling for general characteristics, job stress was significantly related to depression (OR: 1.07, 95% CI: 1.01~1.14). However, job stress became non-significant in the model that included instrumental support from supervisors. Not emotional but instrumental support from supervisors was significantly related to depression of care givers (OR: 0.93, 95% CI: 0.88~0.99). Conclusion: Results of this study suggest that job stress has negative effects and instrumental support from supervisors has protective effects on depression of care givers in elderly care facilities. Therefore, measures to increase instrumental support by supervisors should be developed to improve psychological health of care givers in elderly care facilities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.96-107
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• 2020

This study aimed to identify the associated factors of protective behaviors for radiation exposure among some radiology technologists using the Health Belief Model. The subjects of the study were 541 radiology technologists working at hospitals or clinics in Honam Province. Using the SPSS version 18.0 program, data were analyzed using a t-test, ANOVA, Pearson's correlation analysis, and hierarchical multiple logistic regression analysis. To modify the factors, the performance of subjects who had a higher level of education and nuclear medicine rooms were higher than those who worked in simple radiography rooms. The radiation protective behaviors performance of the subjects who had more exercise, medium-level stress, and worked in higher-quality protection facilities was higher. Regarding the personal perceptions, the cues to action (β=.292, p=.0001), and perceived seriousness (β =.075, p=.010) were factors that had effects on the performance of radiation protection behaviors. Regarding the likelihood of action, the benefits (β=.168, p<.0001), self-efficacy (β=.148, p=.007), and the performance of protective behaviors were higher. In conclusion, protection education as a cue to action should be provided to stimulate protective behaviors, and the benefits of protective behaviors should be emphasized. To increase the performance of protection behaviors, self-efficacy should be enhanced, and the subjects are offered appropriate information that helps perceive seriousness.

• Journal of Sensor Science and Technology
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• v.32 no.3
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• pp.199-206
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• 2023

This study presents a novel monitoring technique for underwater high-voltage direct current (HVDC) cables based on the Distributed Acoustic Sensor (DAS). The proposed technique utilizes vibration and acoustic signals generated on HVDC cables to monitor their condition and detect events such as earthquakes, shipments, tidal currents, and construction activities. To implement the monitoring system, a DAS based on phase-sensitive optical time-domain reflectometry (Φ-OTDR) system was designed, fabricated, and validated for performance. For the HVDC cable monitoring experiments, a testbed was constructed on land, mimicking the cable burial method and protective equipment used underwater. Defined various scenarios that could cause cable damage and conducted experiments accordingly. The developed DAS system achieved a maximum measurement distance of 50 km, a distance measurement interval of 2 m, and a measurement repetition rate of 1 kHz. Extensive experiments conducted on HVDC cables and protective facilities demonstrated the practical potential of the DAS system for monitoring underwater and underground areas.

• Journal of the Korea Safety Management & Science
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• v.15 no.2
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• pp.135-141
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• 2013

As the country's elderly people who are 65 years or older recently exceeded 10% of the total population with development of medical technology and improvement of living standards, Korea has turned into an aging society. Especially in Gyeonggi-do, as of late December 2012, elderly people who were 65 years or older were 1,135,242 persons, taking up 18.98% of the region's population and registering the largest number of elderly people in the nation's cities or provinces. Due to such a sharp rise in elderly population, support for the elderly is increasing the burden on families and communities. The study aims to take as its subjects elderly people staying at authorized elderly welfare facilities, who are weak in mind and body and have difficulty in daily life with disabilities, or adult day care facilities that take care of elderly people during the day or at night, examine the concept of adult day care facilities and instances in foreign countries, and study the status of the adult day care facilities located in Gyeonggi-do, their services, and safety by figuring out space arrangement based on program implementation. Spacial arrangement in program operation should satisfy fuction and purpose from the manager and user's perspective, and a desirable program operation should provide separate spaces for the elderly with Alzheimer's and those without Alzheimer's. Compared to residential care facilities, adult day care facilities incur less financial burden and, compared to other authorized services, have many right functions that can upgrade the quality of users and satisfy their desires. Major countries like Japan, the UK, and Sweden recognize the right functions of day and night care services and aggressively support and utilize adult day care facilities. For adult day care facilities, quality services should be developed and use and choices should be enhanced as regards services. Development of special programs for the elderly with dementia and stroke, instead of simple protective functions of a program, must be actively promoted, while manpower training is required for program operation, conveniences, and safety. By developing and providing space arrangement models that focus on efficiency, convenience, and safety of program operation, adult day care operation can be revitalized, while quality of elderly care may be enhanced and welfare budget can be saved.

• Korean Journal of Heritage: History & Science
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• v.44 no.1
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• pp.182-195
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• 2011

Old big tree transcends the simple meaning of trees as they are the natural monuments that embody the people's history and culture of this land. The Cultural Heritage Administration of Korea (CHA) defines and protects old big tree based not only on the size of the tree but also on its definitive cultural and natural factors such as value, implications, and originality. This research aims to identify and analyze the habitation and measurements, the soil conditions, as well as the protective facilities of 14 old big tree spread throughout the Gangwondo. The research examined the soundness of the arboreal form, the degree of damage on the bark, as well as the quantity of leafs levels to evaluate the overall condition of growth and development. Then, the tree height, the eastwest and south-north width of the crown, the sternum circumference, and the root circumference were recorded to identify the measurements of the selected old big tree. Also, the research analyzed 9 elements such as soil texture, pH levels, and organic contents in order to determine the scientific characteristics of soil upon which the trees draw nutrition. Finally, the research evaluated supporting pillars, lightning rods, iron pulling-facilities, as well as notice boards to study the protective facilities of old big tree. The research procedures revealed that 78.57% of the old big tree identified as natural monuments in the Gangwondo have average to above average habitation conditions. Also, the average tree height reaches 18.80m above ground while the average root circumference measures 7.34m. Moreover, the results of the scientific analyses conducted on the soil elements determined that most chemical values were within the defined levels, with the exception of phosphoric acid levels falling within the hyper-nutritious range. Finally, although most of the protective facilities did support the habitation of the Old big tree, there were some supporting pillars and iron pulling-facilities that actually damaged the trees. This research means to provide foundational reference data for the analysis of the habitation and management conditions of natural monument old big tree within the Gangwondo. A follow-up topic led by the results of this research is the identification and analysis of correlating environmental elements that affect the habitation of the old big tree.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.4
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• pp.61-79
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• 2016

This study aims at examining the structural and managemental problems of the existing fishways which affect the migrations of fishes, and at suggesting alternatives to improve the fishways' efficiency. The study focuses on the fishways constructed in the diversion weirs in the lower reaches of 41 rivers(2 national rivers and 39 rural rivers) in the eastern coast of Korea. Most of water-using facilities in Korean rivers are diversion weirs, and fishways are established as subsidiary facilities of most of the weirs. Among the 58 or so fishways examined in this study, only a few are doing their proper function, and most of them need improvement. This study aims at strengthening those fishways function and increasing their economic efficiency and migration efficiency. Based on the results of this study, the followings are suggested. In case the fishway sticks out downstream from the apron, a subsidiary fishway diverging from the main is suggested to attract fish. The entrance to the subsidiary should head below the raised part of the apron and a pool should be constructed in the connecting part with the main. To attract fish and let the upstream migrators rest for a while, an entrance pool should be constructed in the fishway. Most of the examined fishways have low side walls, which allow the upstreamers to jump out of the fishway. Those side walls are suggested to be raised above the jumping height of target fishes. The exit parts of most fishways are too shallow, or have no grass to protect the fish from the birds. Protective facilities are suggested to keep the birds from entering the fishway. By the time Ice-harbor type and Vertical-slot type fishways are scientifically proved to be defective, the fishway should not diverge from the standard design.

• Convergence Security Journal
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• v.15 no.3_1
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• pp.3-9
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• 2015

With the development of technology, small UAVs are used in various forms. From military UAV to the Amazon drone, the UAVs are applied to increasing fields for its merits which can replace human work more fast and precisely than what human used to do. Yet, the use and development of UAVs cannot be embraced indiscreetly. There exist negative aspects along with its convenience and positive use. In military use, for instance, the use of UAV can handle dangerous missions in place of human beings but at the same time, it can be very threatening weapons that put people in danger of being attacked at unknown time and places. Therefore, this study discusses the safety measures for major national facilities. Through theoretical understanding of UAVs and major national facilities, the study explores into key concepts and reviewed the cases that threatened our nation's safety. The study also makes suggestions on the policies of the use of UAV to secure national safety.