• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.2
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• pp.101-108
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• 2019

This study is analysis of the utilization as a concrete fine aggregate on CGS, a by-product of Integrated coal gasification combined cycle(IGCC). That is, in KS F 2527 "Concrete aggregate," properties of 1~12times to CGS were evaluated, focusing on quality items corresponding to natural aggregate sand(NS) and melted slag aggregate sand(MS). As a result, the distribution of grain shape, safety and expansion were all satisfied with KS standards by physical properties, but the quality was unstable at 7~12times of water absorption ratio and absolute dry density. The particle size distribution was unstable due to asymmetry distribution of coarse particles, and particles were too thick for 7~12times. The passing ratio of 0.08mm sieve was also out of the KS standard at part factor of 7~12times, but chloride content, clay contents, coal and lignite were all satisfactory. Meanwhile, chemical composition was satisfactory except for $SO_3$ in 1~6times, and content and amount of harmful substances were all within the specified value except for F in 7~12times. As a result of SEM analysis, the surface quality and porosity were 7~12times more than 1~6times, and it was the quality was degraded. Therefore, it is necessary to reduce the quality deviation by using separate measures in order to utilize it as concrete aggregate in the future, and if it is premixed with fine quality aggregate, it will contribute positively to solve aggregate supply shortage and utilize circulation resources.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.667-676
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• 2019

In recent years, the occurrence of life and violent crime in the city centered on crime-prone areas has become a big issue, raising the public interest in safety from crime has been higher than ever. As the initial response to crime and the importance of crime prevention are emerging, the government is preparing various measures such as crime prevention service using advanced technology. This project is a demonstration project to select specific target sites and apply that on a trial basis with the main purpose of commercialization of intelligent crime prevention technologies and services. In order to spread the business through the demonstration project, it is expected that the practical economic evaluation as well as the academic and practical value of the project will have a great significance. In this study, the purpose of this research is to derive economic feasibility through technologies and services to be implemented in Indokwon district of Anyang city, which is selected demonstration site of the intelligent security, to promote the spread of business and contribute to the policy activation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.3
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• pp.129-141
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• 2019

In recent years, fast growing cities in Korea are showing signs of being vulnerable to more disasters as their population and facilities increase and intensify. In particular, fire is one of the most common disasters in Korea's cities, along with traffic accidents. Therefore, in this study, we analyze what type of factors affect the fire that threatens urban people. Fire data were acquired for 10 years, from 2007 to 2017, in Jinju, Korea. Spatial distribution pattern of fire occurrence in Jinju was assessed through the spatial autocorrelation analysis. First, spatial autocorrelation analysis was carried out to grasp the spatial distribution pattern of fire occurrence in Jinju city. In addition, correlation and multiple regression analysis were used to confirm spatial dependency and abnormality among factors. Based on this, OLS (Ordinary Least Square) regression analysis was performed using space weighting considering fire location and spatial location of each facility. As a result, First, LISA (Local Indicator of Spatial Association) analysis of the occurrence of fire in Jinju shows that the most central commercial area are fire department, industrial area, and residential area. Second, the OLS regression model was analyzed by applying spatial weighting, focusing on the most derived factors of multiple regression analysis, by integrating population and social variables and physical variables. As a result, the second kind of neighborhood living facility showed the highest correlation with the fire occurrence, followed by the following in the order of single house, sales facility, first type of neighborhood living facility, and number of households. The results of this study are expected to be useful for analyzing the fire occurrence factors of each facility in urban areas and establishing fire safety measures.

• 한국노년학
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• v.37 no.4
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• pp.853-870
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• 2017

This study examined the changes of depression and life satisfaction among the elderly living together in group-home and congregate housing. And in this course, it was to verify the practical effects of the recent government and local authority community life of elderly people by comparing them with the groups of elders living alone. The study was divided into Time 1 and Time 2, and 205 person's data were used for the final analysis. PASW Statistics 18.0 was utilized to analysis the data of this study, because it is difficult to explain the results of this analysis, secondary qualitative research has been used to identify additional contextual information. The major results of this study are as follows. First, the depression of the subjects was significantly improved in the case of living in group-home and congregate housing, and it was significantly worse in the group of elders living alone. Second, the life satisfaction of survey subjects was significantly improved when living in congregate housing, group-home was significantly worse, and the group of elders living alone were not statistically significant but slightly worse. Third, mixed research methods were applied to make accurate interpretation of changes of life satisfaction of the elderly living in group-home. Based on the results of this study, it is possible to establish appropriate measures for the elderly to improve early adjustment and quality of life in community life. And the community life of the elderly can contribute to a real social safety net by solving the blind spot of welfare. At the national level, it can be utilized as a standard reference to improve and strengthen existing policies by providing data that can simultaneously examine the performances and problems of various policies related to housing or the welfare of the elderly.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.183-194
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• 2019

In recent years, the risk of external flooding of major national facilities has increased significantly since 2000 due to the increase in local heavy rainfall events. For important domestic national facilities, it is necessary to analyze the risk of external flooding as flooding in major sites due to heavy rain can cause functional paralysis in major facilities and ultimately lead to massive trouble events. In order to manage the safety of main facilities and its related facilities at a high level, it is necessary to analyze the degree of disaster such as flood depth, flood flow rate, flood time and flood intensity when extreme floods (LIP) are introduced. In addition, the degree of vulnerability of these related facilities should be assessed and risk assessments should be reassessed through linkage analysis that combines the degree of disaster and vulnerability. By calculating a new flood hazard curve for the flood depth and flood intensity in major national facilities under the heavy rainfall conditions through this study, it is expected to be a basis for the waterproof design of important SOC facilities, flood prevention function design, advancement of flood prevention measures and procedures and evaluation of flood mitigation functions.

• Tunnel and Underground Space
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• v.28 no.6
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• pp.528-546
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• 2018

Cases of TBM tunnelling have been consistently increasing worldwide. In many recent subsea and urban tunnelling projects, TBM excavation has been preferably considered due to its advantages over drill and blast tunnelling. Difficult ground conditions are highly probable to appear in subsea and urban tunnels because of the shallow working depth and alluvial characteristics. Under the difficult ground conditions, ground reinforcement measures should be considered including grouting, while it is of great importance to select the optimal grout material and injection method to cope with the ground condition. The benefits from TBM excavation, such as fast excavation, increased safety, and reduced environmental impact, can be achieved by applying appropriate ground reinforcement with the minimum overrun of cost and time. In this report, various grouting methods were reviewed so that they can be applied in difficult ground conditions. In addition, domestic and international cases of successful ground reinforcement for difficult grounds were introduced for future reference.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.203-209
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• 2019

In this work, a new land-specific resistance measuring device (GM) and a measuring probe (Grounding Rod) are connected to the WENNER quadrant as power-line communication (PLC). In groups of two (P1,P2) probes, five to ten probes are installed in series on the ground at intervals of 1m, 2m, 4m, 8m, and 16m, respectively. If the PLC signal from the GMD is detected by the receiver of the Probe 1 (P1) for measurement, the minute voltage and current for measurement flow from the PSD (power supply) attached to the probe to the ground, and then, through the soil between P1 and P2, enters the Probe 1 (P2). The resistance value is then measured by the principle of voltage drop due to ground resistance. Measure the earth resistance every T seconds up to 1 trillion and store the measured data on the Arduino Server mounted on the main equipment. Stored measurement data can be derived from formulas by Ohm's Law and from inherent resistance (here,). Data obtained in real time will be linked to CDGES programs installed on Main PC, enabling data analysis and real-time monitoring of the ground environment on land. In addition, a three-dimensional display is possible with 3D graph support by identifying seasonal characteristics such as temperature and humidity of land (soils). The limitations of the study will require specific application measures of Test Bed for commercial access to a model that has been developed and operated experimentally.

• Journal of the Society of Disaster Information
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• v.14 no.4
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• pp.480-491
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• 2018

Purpose : This study aims to suggest social support composed of organizational support and managerial support would be systematically managed to enhance Disaster Operations Management at Seoul Emergency Operations Center. Method : Emotional labor was used as an independent variable, and organizational commitment was used as a dependent variable to analyze the mediating effects of social support. Results : First, in the aspect of organizational support, the objective evaluation of disaster situation management, disaster situation management emotional labor reduction education and training program development, monitoring of disaster situation management, quality improvement and work imbalance mitigation of firefighters, and emergency coordination managers are needed for systematic work management for emotional labor settlement. Secondly, it is necessary to select competent firefighters in the level of managerial support, to prepare healing measures for structured phased emotional labor for firefighters, and to have counseling competency for managers for emotional labor firefighting officers. Conclusion : In order to improve disaster management ability, education and training programs should be developed to improve organizational commitment based on social support.

• Journal of Sleep Medicine
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• v.15 no.2
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• pp.37-42
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• 2018

Objectives: To assess the effect and safety of transcranial direct-current stimulation (tDCS) in primary chronic insomnia. Methods: A one-month, double-blind, randomized, sham-controlled trial was performed. A total of 7 patients with primary chronic insomnia received tDCS using anodal (n=3), cathodal (n=2), or sham stimulation (n=2). They were followed up at 1 week and 1 month after treatment. The primary outcome measures included improvement in total sleep time (TST), sleep latency (SL), and sleep efficiency (SE) at 1 month follow-up. Results: TST and SE were improved with tDCS at 1 month follow-up in all patients (100%) of the anodal group, one (50%) of the cathodal group, and one (50%) of the sham group. tDCS improved SL at 1 month follow-up in two patients (67%) of the anodal group, one (50%) of the cathodal group, and none (0%) of the sham group. With respect to adverse events, transient itching sensation occurred in one patient of the anodal group. None of the other groups reported adverse events. Conclusions: Our results suggest that tDCS may be effective and safe for treatment of primary chronic insomnia. A larger controlled study needs to be further investigated.

• Journal of Internet of Things and Convergence
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• v.8 no.6
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• pp.65-73
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• 2022

This study identified the level of awareness of dangerous accidents by empirically analyzing the possibility of hazardous accidents at work and the possibility of dangerous accidents due to COVID-19 targeting the participating seniors who are active in the Senior Club, an organization dedicated to job placement for the elderly. The purpose of this study is to provide basic data for preparing measures to improve risk accidents that may occur in organizations in charge of job placement for the elderly and to suggest countermeasures to prevent dangerous accidents. For this purpose, data were collected from the elderly participating in 16 senior clubs in Busan, and 425 of the collected 430 were ultimately used. As a result of this study, first, it was found that the elderly who participated in a job-dedicated institution for the elderly generally perceived the possibility of occupational risk accidents and risk factors due to COVID-19 to be low. Second, it was found that there was a statistically significant difference in the probability of occurrence of hazardous accidents at work according to demographic characteristics during the participation period, and the probability of occurrence of dangerous accidents with COVID-19 was found to have statistically significant differences in the classification and age of the participating elderly. Based on the results of this study, the project manager suggested creating a safety accident management record sheet, preparing a risk management manual, and establishing a risk management system reflecting the individual characteristics of the participants.