• The Journal of Engineering Geology
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• v.27 no.2
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• pp.153-164
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• 2017

The geological factors for causing ground subsidence are very diverse. It can be affected by any geological or extrinsic influences, and even within the same geological factor, the soil depression impact factor can be determined by different physical properties. As a result of reviewing a large number of papers and case histories, it can be seen that there are seven categories of ground subsidence factors. The depth and thickness of the overburden can affect the subsidence depending on the existence of the cavity, whereas the depth and orientation of the boundary between soil and rock are dominant factors in the ground composed of soil and rock. In case of soil layers, more various influencing factors exist such as type of soil, shear strength, relative density and degree of compaction, dry unit weight, water content, and liquid limit. The type of rock, distance from the main fracture and RQD can be influential factors in the bedrock. When approaching from the hydrogeological point of view, the rainfall intensity, the distance and the depth from the main channel, the coefficient of permeability and fluctuation of ground water level can influence to ground subsidence. It is also possible that the ground subsidence can be affected by external factors such as the depth of excavation and distance from the earth retaining wall, groundwater treatment methods at excavation work, and existence of artificial facilities such as sewer pipes. It is estimated that to evaluate the ground subsidence factor during the construction of underground structures in urban areas will be essential. It is expected that ground subsidence factors examined in this study will contribute for the reliable evaluation of the ground subsidence risk.

• Economic and Environmental Geology
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• v.47 no.6
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• pp.635-643
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• 2014

Sustaiable development yield of groundwater in Korea has been determined according to 10 year drought frequency of groundwater recharge in the standard mid-sized watershed or relatively large area of district. Therefore, the evaluation of groundwater impact in a small watershed is hard to apply. Fot this purpose, a novel approach to estimate cell based sustainable development yield of groundwater (SDYG) is suggested and applied to Gyeongju region. Cell based groundwater recharge is computed using hydrological component analysis using the SWAT-MODFLOW which is an integrated surface water-groundwater model. To estimate the potential amount of groundwater development, the existing method which uses 10 year drought frequency rainfall multiplied by recharge coefficient is adopted. Cell based SDYGs are computed and summed for 143 sub-watersheds and administrative districts. When these SDYGs are combined with groundwater usage data, the groundwater usage rate (total usage / SDYG) shows wide local variations (7.1~108.8%) which are unseen when average rate (24%) is only evaluated. Also, it is expected that additional SDYGs in any small district could be estimated.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.68-76
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• 2006

A thermal time-based two-step phenological model was used to project flowering dates of Japanese cherry in South Korea from 1941 to 2100. The model consists of two sequential periods: the rest period described by chilling requirement and the forcing period described by heating requirement. Daily maximum and minimum temperature are used to calculate daily chill units until a pre-determined chilling requirement for rest release is met. After the projected rest release date, daily heat units (growing degree days) are accumulated until a pre-determined heating requirement for flowering is achieved. Model calculations using daily temperature data at 18 synoptic stations during 1955-2004 were compared with the observed blooming dates and resulted in 3.9 days mean absolute error, 5.1 days root mean squared error, and a correlation coefficient of 0.86. Considering that the phonology observation has never been fully standardized in Korea, this result seems reasonable. Gridded data sets of daily maximum and minimum temperature with a 270 m grid spacing were prepared for the climatological years 1941-1970 and 1971-2000 from observations at 56 synoptic stations by using a spatial interpolation scheme for correcting urban heat island effect as well as elevation effect. A 25km-resolution temperature data set covering the Korean Peninsula, prepared by the Meteorological Research Institute of Korea Meteorological Administration under the condition of Inter-governmental Panel on Climate Change-Special Report on Emission Scenarios A2, was converted to 270 m gridded data for the climatological years 2011-2040, 2041-2070 and 2071-2100. The model was run by the gridded daily maximum and minimum temperature data sets, each representing a climatological normal year for 1941-1970, 1971-2000, 2011-2040, 2041-2070, and 2071-2100. According to the model calculation, the spatially averaged flowering date for the 1971-2000 normal is shorter than that for 1941-1970 by 5.2 days. Compared with the current normal (1971-2000), flowering of Japanese cherry is expected to be earlier by 9, 21, and 29 days in the future normal years 2011-2040, 2041-2070, and 2071-2100, respectively. Southern coastal areas might experience springs with incomplete or even no Japanese cherry flowering caused by insufficient chilling for breaking bud dormancy.

• Journal of Hospice and Palliative Care
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• v.7 no.1
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• pp.29-36
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• 2004

Purpose: A quantitative descriptive study aimed to identify the relationships between spiritual well-being and perception attitudes of death in nursing students. Methods: A survey was conducted and 175 data were collected. Collected data were computed and analyzed using SPSS10.0 for Win. 1) Descriptive statistics were used to identify demographic data, and 2) both t-test and ANOVA statistics were used to figure out the relationships between spiritual well-being /or perception attitudes of death and demographic data of the participants. 3) Pearson's correlation coefficient was used to identify the relationships between the two main variables. Results: 1) The mean of spiritual well-being score of the participants was $50.9943{\pm}10.7235$. Significant relationships between religion /or doing economic activity and spiritual well-being were found. 2) The mean of perception attitudes of death was $20.4914{\pm}2.6280$. There were significant relationships between gender /or age and perception attitudes of death among participants. 3) A strong positive relationship between spiritual well-being and perception attitudes of death of participants was also found(r=.261, P=.000). Conclusion: The study results shows that spiritual well-being of nursing students as caregivers of terminal patients is important when the perception of death of terminal patients is considered. Previous studies indicate that caregivers' perception attitudes impact on those of terminal patients. Therefore, it is suggested that not only perception attitudes of death and spiritual well-being in terminal patients, but also those of caregivers are importantly required to consider in educational programs in relation to spiritual care of terminal patients.

• Korean Journal of Social Welfare Studies
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• v.45 no.2
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• pp.65-97
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• 2014

This research aims to figure the different perceptions on the organization-public relationship between military officials and the locals, and the perception on the support military family welfare. In order to analyse their subject point of view, 217 career soldiers and the 191 local residents surveyed during 3 weeks from 10th February to 28th February, 2014. The results getting from this research were as to follows; First of all, the perception on the military organization-public relationship towards local community is more positive in the military officials(M=5.39) than the locals(M=4.99), but different from the two groups(t=6.93, p<.001). Moreover, there exists statistically significant different in every sub-factors and it means the mutual perception consistency is low. Second, the perception on the support from the locals towards military family welfare of military(M=5.38) is higher(t=6.93, p<.001) than the perception of the locals (M=4.76) and it is statistically significant. Third, the a regression coefficient which indicates the impact on the perception on support military family welfare through the change of organization-public relationship shows statistically significant (${\beta}=.82$(p<.001)). As a result, the perception on the military organization-public relationship of the locals has significant prediction power to the perception on the support military family welfare. And when the perception on the military organization-public relationship of the localsis higher, the perception on the support military family welfare has been changed positively.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.1-7
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• 2019

This study analyzed the effects of labor aging on labor productivity using panel statistics of 16 local governments from 1995 to 2017. The aging of the labor force, defined as the proportion of workers aged 60 or older in total employment, in the results of the panel regression analysis considering regional fixed effects and various adjustment variables, has a very consistent and significant negative effect on labor productivity. For every 1% increase in aging, labor productivity decreases by about 0.14 ~ 0.20%. In addition, the per capita capital stock and human capital considered as adjustment variables contributed to the increase of labor productivity, and the unemployment rate, which is a proxy variable of the economic fluctuation, has a significant negative effect on labor productivity as expected. The coefficient of the industrial structure, which represents the share of the service industry in the whole industry, was positive, but is not significant. The results of this study suggest that the design and construction of economic and educational policies that can maintain and expand human capital are necessary to curb the reduction in labor productivity expected by the aging workforce.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1307-1315
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• 2021

The Changjiang Diluted Water (CDW) spreads over the East China Sea every summer and significantly affects the sea surface salinity changes in the seas around Jeju Island and the southern coast of Korea peninsula. Sometimes its effect extends to the eastern coast of Korea peninsula through the Korea Strait. Specifically, the CDW has a significant impact on marine physics and ecology and causes damage to fisheries and aquaculture. However, due to the limited field surveys, continuous observation of the CDW in the East China Sea is practically difficult. Many studies have been conducted using satellite measurements to monitor CDW distribution in near-real time. In this study, an algorithm for estimating Sea Surface Salinity (SSS) in the East China Sea was developed using the Geostationary Ocean Color Imager (GOCI). The Multilayer Perceptron Neural Network (MPNN) method was employed for developing an algorithm, and Soil Moisture Active Passive (SMAP) SSS data was selected for the output. In the previous study, an algorithm for estimating SSS using GOCI was trained by 2016 observation data. By comparison, the train data period was extended from 2015 to 2020 to improve the algorithm performance. The validation results with the National Institute of Fisheries Science (NIFS) serial oceanographic observation data from 2011 to 2019 show 0.61 of coefficient of determination (R²) and 1.08 psu of Root Mean Square Errors (RMSE). This study was carried out to develop an algorithm for monitoring the surface salinity of the East China Sea using GOCI and is expected to contribute to the development of the algorithm for estimating SSS by using GOCI-II.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.911-917
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• 2021

Severe Acute Respiratory Syndrome is being impacted worldwide by the prolonged COVID-19 situation. Due to the impact of COVID-19, domestic educational institutions have also changed their teaching methods. Domestic universities traditionally aim for face-to-face lectures, but due to the pandemic, they are conducting non-face-to-face lectures. This study aims to evaluate the effect of non-face-to-face lectures on radiology students. The subjects of this study are students of the Department of Radiology at University D in Daegu. As for the contents of the study, satisfaction with non-face-to-face lecture delivery, concentration, and comprehension was evaluated. Data analysis was performed in SPSS Ver. 26 was used, and the reliability measurement was found to be Cronbach's alpha coefficient = 0.805. In the results of this study, the satisfaction of non-face-to-face lecture delivery, concentration, and comprehension was overall high. However, satisfaction with theoretical subjects (2.08±0.88) was significantly different from that of practical subjects (2.51±1.10) (t=-9.880, p<.001). Satisfaction by grade level was highest in the first grade. As a result, it is judged that non-face-to-face theoretical lectures require more careful preparation from lecture planning than practical lectures, and further research is expected in the future.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1229-1235
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• 2018

We have examined dynamic relationships among water-efficiency, economic growth, electricity generation, and $CO_2$ emissions in Korea using various time-series analysis methods for 1990-2014. While previous studies have been limited to economic growth, $CO_2$ emissions, and electricity generation, this study contributed to explain the relationship between existing variables and water-efficiency. We find that the four variables reach a balanced state in the long run through short-term adjustment, $CO_2$ emissions and economic growth are responsible for water efficiency, and that $CO_2$ emissions, economic growth and water efficiency are the causes of electricity generation. The long-term impact coefficient estimates on water-efficiency show that the increase in electricity generation and the decrease in $CO_2$ emissions increase water-efficiency. Although economic growth has increased water-efficiency, moreover, we have identified an inverted U-shaped relationship between economic growth and water-efficiency, which suggests that economic growth above a certain level reduces the rate of increase in water-efficiency.

• Korean Journal of Child Education & Care
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• v.18 no.4
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• pp.145-158
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• 2018

Objective: The purpose of this study was to investigate the effects of distribution justice, procedural justice, and interactional justice which are the sub-factors of organizational justice on organizational commitment and turnover intention, so as to enhance the quality of childcare and identify the importance of organizational justice. Methods: For the study, the data were collected by measuring the organizational justice, organizational commitment, and turnover intention of 251 teachers working in home day care centers in Busan, Ulsan, and Gyeongnam, and then Pearson's product moment correlation coefficient and regression analysis (stepwise) were conducted. Results: The results are as follows. First, organizational commitment was significantly different in the age in terms of the general background of daily care teachers, as well as the period of service of their current organization, and the turnover intention showed a significant correlation with their salary. Second, the sub-factors of organizational justice and organizational commitment were positively correlated, but turnover intention was negatively correlated. Among them, in terms of organizational commitment, procedural justice and turnover intention were highly correlated with distribution justice. Third, the relative impact of the sub-factors of organizational justice on organizational commitment was high in procedural justice and distribution justice. The relative influence on turnover intention was high in distribution justice and interactional justice. Conclusion/Implications: Therefore, the results of this study indicate that organizational justice is a influential variable on organizational commitment and turnover intention, and suggest that it needs to make efforts to strengthen organizational justice for the operation of home daycare centers.