• 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.

• Journal of Korean Library and Information Science Society
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• v.49 no.4
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• pp.295-328
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• 2018

This study aims to analyze circulation status of children's material and participation in culture program based on the bigdata to identify the current status of children and youth services and suggest ways to improve the services. The logs to be analyzed consist of children's material information, circulation count information, circulation user information registered at the National Library of Korea, Sejong. The children's material information logs contain 77,297 data, circulation count information logs contain 4,160,484 data, circulation user information logs contain 189,060 data The current status analysis of children and youth services was conducted in various ways, including analysis of circulation status and culture program by subject, age, and residential area. Based on analysis results, improvement methods of children and youth services were proposed in terms of books, users and residences. This study analyze empirically current status of children and youth services based on bigdata logs, and it has significance for being different form proceeding researches. We expect this study to be used as an empirical basis for the establishment of operational strategies in the future.

• The Journal of the Acoustical Society of Korea
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• v.38 no.3
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• pp.352-362
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• 2019

The old residences and shops in the backside blocks are affected by the traffic noises from the main road. The noise of the backside roads is affected by the following factors such as the height of the roadside buildings, the distance between the road and the backside streets, distance among adjacent roadside buildings, and the difference of the adjacent building heights. The both noise levels on the road and the backside street were measured simultaneously in 15 urban blocks of a city which can be categorized into two types of roadside building plans ; 1) one single building along the street, 2) buildings arranged on one axis beside the road. As the results, there is no significant noise reduction due to the width of the buildings in general. However, in the cases of buildings arranged on one axis beside the road, it was found that the average noise reduction was 12 dB(A) on the basis of the building height of 4 m. Also, it was analysed that for each 4 m increase in the building height, noise reduction occurred by 2 dB(A) beyond building height of 4 m. In general, it was proved that the noise of the back streets is mainly affected by the lowest height of the roadside buildings. It was found that noise is increased by 1 dB(A) for each 4 m increase of the height difference between adjacent buildings. Also, It was revealed that for each 0.5 m increase in the distance between roadside building, noise reduction decreased by 1 dB(A).

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.32-51
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• 2021

Architectural evidence of Gaya is insignificant than any other area. In this situation, house-shaped earthenware is particularly helpful in the study of Gaya architecture. However, house-shaped earthenware is not a building, it has just the shape of buildings. So, we have to find out architectural evidence from that. In this paper, I tried to estimate the architectural characteristics of Gaya through house-shaped earthenware in detail. I also consulted historical records, archeological results, and other scholars' papers. The results are as follows. First, house-shaped earthenware can be classified into three types according to its shape, and each type has distinct architectural structural characteristics. Second, house-shaped earthenware generally has a gambrel roof, and the characteristic of architectural design with the gable side of the gambrel roof as a front is the biggest feature of Gaya architecture. Third, various types of buildings existed according to their functions in Gaya architecture, and house-shaped earthenware was showed buildings of ancient storage, pens, and residences, which are symbols of the richness among various types of buildings.

• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.195-201
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• 2022

There was a report that the prevalence of gallbladder polyps (GBPs) and some clinical variables were different between the urban and rural area, which was performed in a mainland. Thus the previous report could have some confounding factors. Therefore, the purpose of this study was to compare the prevalence of GBPs and clinical variables on the isolated island to exclude extrinsic confounding factors. We compared the prevalence of GBPs and clinical variables among 21,734 residents who visited a single medical check-up center in Jeju National University Hospital from January 2010 to December 2019 according to their residences on Jeju Island. The prevalence of GBPs were 10.1% in the urban area 8.7%, respectively (P = 0.006). Among clinical variables, the rate of central obesity, the mean levels of fasting blood glucose, low density lipoprotein-cholesterol, alkaline phosphate and gamma-glutamyltransferase and the mean age among residents in the rural area was statically higher in the urban area; however, the mean total cholesterol level among residents in the urban area significantly higher than in the rural area. This study showed that the prevalence of GBPs and some clinical variables among residents were statistically different between the urban area on Jeju Island.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.10
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• pp.895-903
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• 2018

The purpose of this study is to conduct a comparative analysis on the mental health and health-related quality of life of the community residents who have been affected by the Sewol ferry disaster and to provide a basis for future aids for potential human-caused catastrophe. The study utilized the big data, Korean community health survey data of 3,632 (1,803 in 2018 and 1,829 in 2014) residents in Ansan and Jindo, a victimized community of Sewol ferry disaster, and compared the subjective level of health, amount of appropriate sleep, subjective stress level, stress consulting, depression, depression consulting, and health-related quality of life before and after the disaster. According to the findings, community residents who have been affected by the Sewol ferry disaster did not show any significant difference in terms of subjective health level, amount of appropriate sleep, subjective stress, and health-related quality of life. The study aims to serve as a foundational data for developing a prevention program or policy that aims to support future potential disasters by comparing the mental health and health-related quality of life of the victimized community before and after the disaster. The study suggests that the need for continuous monitoring of mental health and health-related quality of life of the victimized residents is significant, and further studies should be implemented in order to provide better supports for the local community.

• Fire Science and Engineering
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• v.29 no.4
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• pp.15-20
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• 2015

This study compared, through a fire simulation, temperature changes of the smoke layer and the air layer, and height fluctuations of the smoke layer, according to the sprinkler head installation and non-installation, and the sprinkler head types in elderly-care facilities. When a standard response sprinkler worked, the radiant heat exceeded the conditions for the occurrence of flashover. However the ESFR sprinkler prevented flashover. When the early response head worked, inhabitants were not damaged by radiant heat because the maximum value of the heat flux remained $2,293W/m^2$, which is less then the burn hazard criterion of $4,000W/m^2$. The highest temperature of the room when fire occurred exceeded the safety standard in all of the smoke layer and the air layer, but the highest temperature was kept below the safety standard after it fell down rapidly. Because the height of the smoke layer was maintained above 1.1 m when the early response sprinkler worked, the falling of the smoking layer was much more delayed than in the case where the standard response sprinkler was used.

• Journal of Korea Entertainment Industry Association
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• v.13 no.6
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• pp.341-351
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• 2019

This study examines factors related to the safety of housing for elderly people. Because of the diverse problems that may occur due to aging, elderly residents may have special needs related to housing. To identify relevant factors, first, focus group interviews were conducted with six individuals aged 65 or older. Then, a Delphi survey was conducted on experts; this survey consisted of a questionnaire on factors related to the safety of housing for elderly people. Issues to address in the questionnaire were identified in the focus group interviews and also through an examination of literature published domestically and overseas. In the Delphi survey, opinions were collected from the experts; these opinions were then revised, collated, and analyzed. The factors identified in these steps were verified using a content validity index. As a result, a total of seven primary factors - outdoor environment, entrance, indoor environment, living room, bedroom, kitchen, bathroom, and restroom - and 23 sub-factors related to elderly people's housing safety were identified. The most frequently mentioned factors were indoor and outdoor stairs, safe flooring materials, and indoor thresholds. It is essential to identify the factors that most affect the safety of elderly people in their residences.

• Journal of Environmental Health Sciences
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• v.49 no.5
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• pp.251-261
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• 2023

Background: This paper deals with the study of natural radioactivity in rocks from Ogun State in Southwestern Nigeria. The aim is to determine radiation emissions from rocks in order to estimate radiation hazard indices. Objectives: The following objectives were targeted: 1. To determine radiation emissions from each type of rocks; 2. To estimate radiation hazard indices based on the rocks; 3. To correlate the activity concentrations of radionuclides with major oxides. Methods: The samples were analyzed using a NaI (Tl) gamma ray spectrometric detector and PerkinElmer AAnalyst 400 AAS spectrometer. Results: The activity of ⁴⁰K, ²²⁶Ra, and ²³²Th were found in order of decreasing magnitude from pegmatite>granite>migmatite. In contrast, lower concentrations were found in shale, phosphate, clay stone, sandstone and limestone. The mean absorbed doses were 125±23 nGyh^-1 (migmatite), 74±13 nGy/h (granite), 72±13 nGyh^-1 (pegmatite), 64±09 nGyh^-1 (quartzite), 45±16 nGyh^-1 (shale), 41±09 nGyh^-1 (limestone), 41±11 nGyh^-1 (clay stone), 24±03 nGyh^-1 (phosphate), and 21±10 nGyh^-1 (sandstone). The outdoor effective dose rates in all rock samples were slightly higher than the world average dose value of 0.34 mSvy^-1. The percentage composition of SiO₂ in the rock samples was above 50 wt% except for in the limestone, shale and phosphate. Al₂O₃ ranged from 4.10~21.24 wt%, Fe₂O₃ from 0.39~7.5 wt%, and CaO from 0.09-46.6 wt%. In addition, Na₂O and K₂O were present in at least 5 wt%. Other major oxides, including TiO₂, P₂O₅, K₂O, MnO, MgO and Na₂O were depleted. Conclusions: The findings suggest that Ogun State may be described as a region with elevated background radiation. It is recommended that houses should be constructed with good cross ventilation and residences should use home radiation monitoring instruments to monitor radon emanating from walls.

• Journal of Environmental Health Sciences
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• v.50 no.1
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• pp.16-24
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• 2024

Background: Indoor PM_2.5 concentrations in residential houses can be affected by various factors depending on the season. This is because not only do the climate characteristics depend on the season, but the activity patterns of occupants are also different. Objectives: The purpose of this study is to compare factors affecting indoor PM_2.5 concentrations in apartments and detached houses in Daegu according to seasonal changes. Methods: This study included 20 households in Daegu, South Korea. The study was conducted during the summer (from July 10 to August 10, 2023) and the autumn (from September 11 to October 9, 2023). A sensor-based instrument for PM_2.5 levels was installed in the living room of each residence, and measurements were taken continuously for 24 hours at intervals of one minute during the measurement period. Based on the air quality monitoring system data in Daegu, outdoor PM_2.5 concentrations were estimated using ordinary kriging (OK) in Python. In addition, the indoor activities of the occupants were investigated using a time-activity pattern diary. The affecting factors of indoor PM_2.5 concentration were analyzed using multiple regression analysis. Results: Indoor and outdoor PM_2.5 concentrations of the residences during summer were 15.27±11.09 ㎍/m³ and 11.52±7.56 ㎍/m³, respectively. Indoor and outdoor PM_2.5 concentrations during autumn were 13.82±9.61 ㎍/m³ and 9.57±5.50 ㎍/m³, respectively. The PM_2.5 concentrations were higher in summer compared to autumn both indoors and outdoors. The primary factor affecting indoor PM_2.5 concentration in summer was occupant activity. On the other hand, during the autumn season, the primary affecting factor was outdoor PM_2.5 concentration. Conclusions: Indoor PM_2.5 concentration in residential houses is affected by occupant activity such as the inflow of outdoor PM_2.5 concentration, cooking, and cleaning, as found in previous studies. However, it was revealed that there were differences depending on the season.