• Journal of Nutrition and Health
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• v.52 no.3
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• pp.258-267
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• 2019

Purpose: Upper respiratory tract infections are major causes of the common cold throughout the world. Cordyceps militaris (C. militaris) is a well-known functional food for its anti-fatigue and immunomodulating activities. On the other hand, there are no reports on the protective effect against upper respiratory tract infections (URI). This study was a 12 week randomized, double-blind, and placebo-controlled trial in healthy volunteers. Methods: A total of 100 subjects 20 ~ 70 years of age with a history of at least two colds in the year were enrolled in the study. The participants were required to record any adverse events and rate any cold-related incidents in a diary during the investigation period. The efficacy end point was the symptoms and incidence of URI, and changes in cytokines, IgA and natural killer (NK) cell activity. Results: The Cordyceps militaris group over 12 weeks showed no significant impact on the incidence and symptomatology of URI compared to the placebo group. On the other hand, the experimental group showed significantly higher NK cell activity (p = 0.047) and IgA level (p = 0.035) compared to the placebo group. The NK-cell activity and IgA level were increased significantly by Cordyceps militaris over 12 weeks. Conclusion: The results suggest the possible beneficial immunomodulating effects, but the protective effects on URI could not be demonstrated under these conditions. Additional research will be needed to determine the efficacy and mechanisms of Cordyceps militaris function.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.9-20
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• 2019

The number of natural disasters in Korea, such as earthquakes, is increasing. As a result, there is growing need for temporary residences or shelters for disaster conditions. The aim of this study was to produce post-disaster refugees housing differentiated from existing shelters using lightweight composite panels. To accomplish this, the structural performance of lightweight composite panels was validated, and an in-plane shear strength test was conducted according to the ASTM E72 criteria among the performance test methods for panels. As a result of the experiment, the maximum load for each specimen under an in-plane shear load was determined. All the experiments ended with the tear of the panel's skin section. The initial stiffness of the specimens was consistent with that predicted by the calculations. On the other hand, local crushing and tearing, as well as the characteristics of the panel, resulted in a decrease in stiffness and final failure. Specimens with an opening showed a difference in stiffness and strength from the basic experiment. The maximum load and the effective area were found to be proportional. Through this process, the allowable shear stress of the specimens was calculated and the average allowable shear stress was determined. The average ultimate shear stress of the lightweight composite panels was found to be $0.047N/mm^2$, which provides a criterion of judgement that could be used to expect the allowable load of lightweight composite panels.

• Korean Journal of Family Social Work
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• no.55
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• pp.265-297
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• 2017

This study aims to provide basic information about the policy and system improvements relevant to single elderly men, through an investigation concerning the use and needs of activity spaces near their housing environments. Eighteen single elderly men over 60-years-old living in Gunsan city of Jeonbuk province in Korea participated in in-depth interview, and the data were qualitatively analyzed. The results of the study are as follows: The social networks of the participants were focused on friends or colleagues, while mutual exchanges with their children were intermittently undertaken. Natural networks of the elderly were formed mainly in third places, such as parks, restaurants, or community facilities, and about a half of the elderly participants had no spatial needs, and the rest required spaces for meal services, the elderly living community, jobs, leisure/hobby activities, or facility improvements. The elements influencing use of activity spaces were access from the residence, health, social networks, and economic conditions. The results suggest the following: Exercise or leisure facilities supporting elderly mobility should be set up close to their residential environments. Senior facilities centered on systematic supports and shuttle buses circulating around the places that the elderly visit frequently should be considered. On the other hand, regular maintenance and education on residents' proper use of the facilities, and sufficient information and fee discounts for the general programs are needed so that the elderly could interact with the younger generation. From a public perspective, a rational system and policy based on understanding single elderly men's needs should be prepared for provision and management of the activity space.

• Journal of Korea Water Resources Association
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• v.52 no.4
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• pp.301-312
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• 2019

The importance of the dual drainage system model has increased as the urban flood damage has increased due to the increase of local storm due to climate change. The dual drainage model is a model for more accurately expressing the phenomena of surface flow and conduit flow. Surface runoff and pipe runoff are analyzed through the respective equations and parameters. And the results are expressed visually in various ways. Therefore, inundation analysis results of dual drainage model are used as important data for urban flood prevention plan. In this study, the applicability of the COBRA model, which can be interpreted by combining the dual drainage system with the natural watershed and the urban watershed, was investigated. And the results were compared with other dual drainage models (XP-SWMM, UFAM) to determine suitability of the results. For the same watershed, the XP-SWMM simulates the flooding characteristics of 3 types of dual drainage system model and the internal flooding characteristics due to the lack of capacity of the conduit. UFAM showed the lowest inundation analysis results compared with the other models according to characteristics of consideration of street inlet. COBRA showed the general result that the flooded area and the maximum flooding depth are proportional to the increase in rainfall. It is considered that the COBRA model is good in terms of the stability of the model considering the characteristics of the model to simulate the effective rainfall according to the soil conditions and the realistic appearance of the flooding due to the surface reservoir.

• Korean Journal of Heritage: History & Science
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• v.35
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• pp.28-56
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• 2002

There is no definite theory, which archeologists have believed to be built either for the protection or ceremonial purpose, of enclosure historical site exhibited from Bronze Age to Samhan era in Korea. The main conditions of choosing right enclosure were natural levee-backswamp-plateau, which all found in village on a hill. For this reasons Kimhae Daesoeng-dong enclosure discovered in 2001 is not an exception, and therefore this enclosure has been believed to be a beginning point of the farming society. In Korea there have been 2 types of enclosure. One is that enclosure entirely surrounds whole historic site itself and the other is that enclosure partially does. Although Kimhae Daesoeng-dong historic site has been discovered only part of it, it's not believed to have the first type-which surrounds the whole enclosure historic site In this research, 3 developing steps of enclosure historic site were defined. Enclosure surrounds only a part of the historic site is 1st step. Enclosure surrounds all around the site is 2nd step. The site discovered with big round clay pottery and developed into multiple enclosure is 3rd step. Since some researches have not been accomplished, the hypothesis above was suggested to have a better understanding of the development of enclosure historic site. The purpose of enclosure has been separately explained for the protection or for the ceremony. It is difficult to assert that excavation sites could be applied to only one of two purposes. But it is possible that both purposes of enclosure such as protection and as division from ceremonial area could be applied together. Kimhae Daesoeng-dong enclosure was shown for the purpose of division from ceremonial area. But we can not ignore that since Kimhae Daesoeng-dong enclosure exposed to the Sea and dwelling area was not shown from village hill, it would be probably for the protection. However enclosure of Gujibong village area in Daesoeng-dong had used for ceremonial purpose since the Bronze Age, even this enclosure would be possible to play an important role of being a center of legend of Gaya foundation. Many unsolved questions are still lying ahead. The enclosure was used for a short time, even if dwelling area was found in and out of enclosure, there were no differences between them, and although duplicate and triplicate enclosure were found, we could not sure which were before and after. Also we could not confirm the type of enclosure with location condition which was the flat land or the top of hill on floodplain. We should not divide the types of enclosure historic site due to differences from cross section of stratum. And I expect that we will have much data such as distribution of enclosure historic site in Yeongnam area where is concerned with origin and diffusion of Japan and China.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.309-326
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• 2004

There are some methods such as fatty acid analysis and microscope analysis of parasite egg and pollen and genetic analysis of ancient bacteria from ancient soil. The fatty acid analysis can examine whether some materials is human feces or animals. This is important thing to reconstruct ancient toilet culture pattern. The methods using TLC and GC-MS as organic chemistry is able to confirm ancient diet life style and nutritive conditions. The microscope analysis of ancient soil is able to confirm ancient parasite egg and pollen. It is possible to analogize ancient human diseases from this analysis. Also, genetic analysis is able to confirm genetic diversity and variation pattern of ancient organisms in archeological soil. Most of all, it is convinced of carrying through genetic preservation of exterminated ancient organisms. If archeological soils should be analysed through the natural scientific methods such as organic chemistry, soil science, microbiology, molecular biology, and genetics, this is helpful for us to understand and interpretation past historic event. And it is expected to perform an major role for understanding origin of ancient human and life style.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.541-552
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• 2018

The implementation of drought measures in the upstream areas of river basins is seldom considered with respect to water supply. However, the demand for such measures is increasing rapidly owing to the occurrence of severe droughts, and interventions on streams and the water supply are needed. Physical interventions are an option to prevent streams from becoming dry and to maintain stream water flow, but dam construction is challenging because of environmental and ecological considerations. Here, a feasibility study was conducted to assess the potential effects of sand dams, which are widely used in arid regions in Africa. The SWAT-K model, which is a hydrologic model used for Korean watersheds, is used to estimate the flow rate of water in an ungauged watershed. The changes in water storage of the sand-dammed reservoir and in downstream flow rates are estimated for two types of sand dam (natural and dredged). The results show that sand dams are capable of increasing the downstream flow rate during normal conditions and of mitigating water supply problems caused by the withdrawal of water during drought periods.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.311-321
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• 2019

Greenhouse farmers often use thermal screens to reduce greenhouse heating expenses during the winter, and for shade during hot, sunny days in the summer, as it is an inexpensive solution to temperature control relative to other available options. However, accurate measurements of their emitted and absorbed radiations are important for the selection of suitable screens that offer maximum performance. Material's ability to save energy is highly dependent on these properties. Limited studies have investigated the measurement of these properties under natural conditions, but they are only applicable to materials having partial porosities. In this work, we describe a new radiation balance method for determining emissive power and absorptive capacity, as well as reflectivity, transmissivity and emissivity of materials having complete and partial transparency by using pyrgeometer and net radiometer. In this study, four materials with zero porosity, were tested. The emissivity value of PE, LD-13, LD-15 and PH-20 was $0.439{\pm}0.020$, $0.460{\pm}0.010$, $0.454{\pm}0.004$, and $0.499{\pm}0.006$, respectively. All tested samples showed high emitted radiation as compared to absorbed radiation.

• Journal of The Korean Association For Science Education
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• v.40 no.6
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• pp.621-630
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• 2020

This study compared and analyzed the contents of secondary earth science curriculum in Mongolia and South Korea to check the contents of earth science education in both countries and to prepare basic data necessary for future earth science curriculum revisions. The research questions of this study are: first, to understand the changes and current operating conditions of earth science curriculum in both countries, to compare and analyze with other foreign cases, and second, to compare and analyze the contents of earth science and curriculum in both countries. The TIMSS evaluation framework is used to compare and analyze the earth science-related contents included in the science curriculum of middle schools. For analyzing the contents of high school, the contents of NGSS in the United States and the earth science curriculum contents of high schools in South Korea were mixed and the analysis frameworks were created and validated by experts. As a result of the study, countries that follow the Russian-style education system did not organize and operate earth science as an independent science subject, and deal with earth science-related content in the natural geography area of the geography subject. The earth science contents covered in middle school science curriculum in both countries, 18 of the 27 content elements of the TIMSS content analysis framework were matched in Mongolia and 20 in South Korea. In high school curriculum, the contents of earth science in Mongolia were described more briefly and not covered than in South Korea. In particular, the Mongolian geography curriculum dealt with many environmental issues. The emphasis on the operation method of the earth science curriculum in Mongolia and the contents related to the environment can be used as a reference when developing an interdisciplinary integrated curriculum of science and social studies in South Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.1
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• pp.21-28
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• 2021

The main purpose of this study is to assess the safety of the fixed anchorages subjected to the seismic motion for an operating facilities in the actual power plant. Thus, the experimental study was conducted to investigate the load response in the event of an actual seismic to the anchorages of a nonstructural components. Since there are economic and spatial constraints to study nonstructural components that actually have various forms, alternative test specimens of steel frames with mass were built and the shaking table test was carried out. In order to evaluate the dynamic characteristics and seismic performance, the natural frequency of the target structure was identified through the shaking table test and then the load response characteristics of the anchorage were evaluated by generating an artificial seismic effect like actual seismic. Finally, the structural stiffness was reinforced by fixing the steel frame to the test specimen using bolts, thereby reducing the load transmitted to the anchorage. It will be carried out on the reliability verification of the experiments and areas that have not been carried out due to the site conditions through the analytical approach in the future.