• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.346-353
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• 2020

The purpose of this study was to explore types of longitudinal changes in interactions between mothers and 4-year-old children in primary school as well as the effects on media device addiction. To explore interaction types between mothers and children, latent class growth modeling (LCGM) and BCH were used in a three-step approach. Data from the 6-10th wave of the Panel Study of Korea Children were used. First, the trajectory of the mother-child interactions was linear and decreased across time. This linear decrease was classified into the following three trajectories: high-decreasing, average-deceasing, and low-decreasing. Second, BCH was performed to examine media device addiction in each trajectory, and the findings show that children who had low initial mother-child interactions over time were more likely to experience daily disturbances in adaptive functions such as withdraw or tolerance than other groups of children. The results indicate that maximizing the quality of mother-child interactions in childhood through primary school can lower media device addiction in children.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.400-406
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• 2018

In this experiment the effect of supplemental lighting on the growth and yield of cucumber (Cucumis sativus L. 'Fresh') plants during low radiation period of winter season were investigated in glasshouses using common high-pressure sodium (HPS) lamps and newly developed plasma lighting system (PLS) lamps. Plants grown without supplemental lighting were considered as a control. Supplemental lighting was provided from November 20th, 2015 to March 15th, 2016 to ensure 14-hour photoperiod (natural+supplemental light), also lamps were operated automatically when the outside sun radiation levels were less than $100W{\cdot}m^{-2}$. Spectral analysis showed that HPS lamp had a discrete spectrum, lacked of the radiation in the 400-550 nm wave band (blue-green light), but had a high output in the orange-red region (550-650 nm). A higher red light output resulted in an increased red to far-red (R/FR) ratio in HPS lamp. PLS had a continuous spectrum and had a peak radiation in green region (490-550 nm). HPS has 12.6% lower output in photosynthetically active radiation (PAR) but 12.6% higher output in near infra-red (NIR) spectral regions compared to PLS. Both HPS and PLS lamps emitted very low levels of ultra-violet radiation (300-400 nm). Supplemental lighting both from HPS and PLS lamps increased plant height, leaf number, internode number and dry weight of cucumber plants compared to control. Photosynthetic activity of cucumber plants grown under two supplemental lighting systems was comparable. Number of fruits per cucumber plant (fruit weight per plant) in control, PLS, and HPS plots were 21.2 (2.9 kg), 38.7 (5.5 kg), and 40.4 (5.6 kg), respectively, thereby increasing yield by 1.8-1.9 times in comparison with control. An analysis of the economic feasibility of supplemental lighting in cucumber cultivation showed that considering lamp installation and electricity costs the income from supplemental lighting increased by 37% and 62% for PLS and HPS lamps, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.517-524
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• 2020

In line with the recent wave of the 4th Industrial Revolution, the environment for defense R&D is transforming into a center of high-tech military technology. In particular, developed countries are strengthening control of technology exports and technology transfer to protect advanced defense science and technology. For this reason, the budget demand for securing the ability to develop independently high-tech weapons and core technologies suitable for the future battlefield environment is increasing, and increasing efficiency in R&D investment has been highlighted for efficient distribution of limited budgets. This study examined the efficiency of the defense basic R&D project using the non-parametric approach, DEA. The R&D budget, R&D researcher, and R&D period were selected as the input variables, and the number of papers and patents were used as output variables. The efficiency of basic R&D projects was analyzed through CCR, BCC models, and SE. Lastly, based on the efficiency measurements, the cause of the inefficiency of R&D projects was suggested, and ways to improve efficiency were suggested. This study is expected to be used as useful information that can be applied to project performance management through efficiency analysis of basic defense R&D projects and be reflected in the project planning stage through feedback.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.34-40
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• 2017

In recent years, global warming has caused abnormal weather phenomena. Unusually cold climates have occurred all around the world, including cold waves in the Northeastern United States, Beijing, China, Southern India, and Pakistan, as well as floods in Chile, Kazakhstan, and Vietnam. China has been experiencing a nationwide heat wave annually since the year 2013, especially in the southern region. In this study, we used Landsat 8 OLI TIRS sensor images from four periods to analyze the characteristics of abnormal high temperature phenomena in Cixi-si, China. Land cover classification was performed using 10 bands of satellite imagery, and the surface temperature was extracted using the 10th thermal band. The results of the land cover classification of the fourth period show the changes of the time series quantitatively. The results of the surface temperature calculation provided both the average overall temperature and the average temperature of individual items. The temperature was found to be highest for buildings, followed by grassland, forest, agricultural land, water systems, and tidal flats in the same period.

• Journal of Korean Home Economics Education Association
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• v.29 no.4
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• pp.101-116
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• 2017

This study aimed to investigate the determinants of confidence in courtship and marriage, childbirth and parenting of the unmarried employed of the echo boomers born between 1982-1992, using data from the 19th wave of the nationwide Korea Labor and Income Panel Study. The differences of confidence in courtship, marriage, childbirth, and parenting of the echo boomers according to sociodemographic variables, psychosocial variables, workplace related variables were examined and multiple regression analysis was conducted in order to identify the factors that affect the confidence in courtship and marriage, childbirth and parenting. The results were as follows: The level of confidence in courtship and marriage, childbirth and parenting showed a statistically significant difference depending upon socioeconomic status and psychosocial variables. However, among the workplace related variables, other than childbirth and parenting within the job satisfaction category, all other variables showed a statistically significant difference. In addition, as the determining factors affecting all issues of courtship, marriage, childbirth, and parenting, youth perceptions of Korean society revealed to be the most influential factor, followed by social support and organizational commitment.

• Journal of Korea Water Resources Association
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• v.38 no.3 s.152
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• pp.213-222
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• 2005

This study is a sensitivity analysis of the parameters which affect the simulation results under various design rainfall conditions, using the SWMM model, for three selected basins in urban areas. The sensitivity of the peak flow rate is defined by $S_Q$ (=1.0 - (min. ratio of peak flow rate/max. ratio of peak flow rate)), and the rainfall conditions are classified in terms of design rainfall frequency, duration, and distribution. The simulation results show that in most conditions the parameters - the impermeable area ratio, the sewer slope, and the initial infiltration capacity - have more significant effects on the results than other parameters. As the design rainfall frequency increases, the sensitivity of the sewer slope and sewer roughness increases, while the parameters related with the surface runoff decrease. When the rainfall duration increases, the sensitivities of most parameters of surface runoff and sewer flow decrease. Also, at the 1st quarterly Huff rainfall distribution condition, the impermeable area ratio has high sensitivity, but at the 4th quarterly condition the parameters related with sewer flow show higher sensitivities. These tendencies can be explained by considering the procedure for computing the effective rainfall and kinematic wave on the surface and sewer flow.

• Journal of Digital Convergence
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• v.18 no.8
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• pp.21-27
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• 2020

This paper studies the impact of domestic and foreign economic activity on mobility among regions. The shortage of human resources and demand continues in Eastern Europeans. Especially Ukrainians, have entered the Polish labor market to make up for the scarce areas. As a result, Poland's supply and demand in Ukraine is disproportionate. Minimum wage increases are putting continued pressure on employers. Therefore, the regression equation in the form of job-seeker's economic activity ratio, y= AX²+B,(x=settlers) can be used to grasp the relationship between curves. According to the domestic and foreign workers who migrated, economic activities was rather than increasing the local population, the settlers of nearby large cities is more proportional. Empirical analysis has shown that the human resource hub has increased migration to large cities and industrial. The hub 'A'nation has been created for mobility in 4th wave re-industry, and the same re-industrialization (N₂) in other cities has attracted nearby human resources, but not settle. After all, the hub relationship between N₁ and N₂ is a mobile relationship. Due to wage inequality or a positive wellbeing chasm, workers are not settled plant area but a nearby city, or commuting between borders is easy to go into the hub central city. However, this proved on emerging from the relatively temporary settlers in the AI era.

• The Korean Journal of Physiology
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• v.5 no.1
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• pp.59-69
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• 1971

Studies were undertaken on the changes in the renal blood flow by relating them with the alterations in the amplitudes in the rheogram of rabbits. The changing pattern of the electrical conductivity was recorded by means of the needle electrodes inserted into the kidney and the surrounding aluminium foil which was grounded. The Impedance Rheograph manufactured by the Narco Company was used. The small artifact which persisted after ligation of the renal vessels was subtracted from the value obtained in each pulsatile wave in the rheogram. The animals were nembutalized intravenously, 30 mg/kg. A plastic canule was inserted into the carotid artery and the arterial blood pressure was monitored continuously with the pressure transducer connected to the physiograph. Stepwise bleedings were performed on the animal. The first bleeding was between 13 to 18 ml in the amount, and it was folowed by consecutive hemorrhages, 5 or 10 ml each time. The total amount of bleeding was summed as much as 1.5-2% of the body weight. Two minutes fter each bleeding th arterial blood pressure, ECG and the rheogram were taken. That was the necessary time to obtain the stabilized picture of each parameter. After closing the bleeding process, the shed blood was retransfused into the animal and the response in the renal blood flow was observed as well as the arterial blood pressure. Particularly the presence or absence of the autoregulatory mechanism in the situation of the hemorrhage was also studied. The results obtained were as follows: 1. In 7 cases out of 22, that was about one third of the total number of experiments, the autoregulatory mechanism of the renal blood flow persisted even in acute hemorrhage, and the decreases in the renal blood flow were less than 10% of the control values even when the arterial blood pressure dropped to 66-87% of the original value obtained before the bleeding. 2. Because of the stepwise bleeding the exact blood pressure at which the renal blood flow reduced as much as one third of the control value could not be obtained. However, the results revealed that the approximate pressure, expressed as percentage of the control value, was 50-60% in 3 cases, 61-70% in 4 cases and 71-80% in 8 cases. In one case the decrease in the renal blood flow exceeded one third of the control value before the pressure dropped to 80% of the control. 3. In 19 cases the decreases in the renal blood flow exceeded one half of the control values by hemorrhage. Then the arterial blood pressure revealed less than 40% of the control value in 6-cases. In 2 cases the pressure was 51-60% of the control pressure. In 5 cases the range of bleed pressure was 61-70%, and in e remaining 6 cases the pressure ranged from 71 to 80% of e control value. 4. Out of 15 cases of retransfusion after definite decreases in the renal blood flow loller·ing the hemorrhage, 9 cases restored their renal blood flow. On the contrary 6 cases showed low values even when the shed blood was retransfused. 5. Theories concerning the mechanism of the autoregulation of the renal blood flow were reviewed for the purpose of explanation of the results obtained. However, there are much to be done before greater satisfaction

• Korean Journal of Social Welfare Studies
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• v.48 no.4
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• pp.91-120
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• 2017

This study aimed (a) to examine the association between chronic illness and multidimensional disability(i.e., psychological/emotional functions, activity capacity, and participation frequency) among older adults with disabilities, (b) to investigate the effect of formal and informal supports on multidimensional disability, and (c) to analyze the moderating effects of formal and informal supports on the association between chronic illness and multidimensional disability. This study used 2014 Korea Welfare Panel Study(the 9th wave) data and 450 older adults with disabilities aged 50 and over were selected as the study target. The research model was analyzed by structural equation modeling using IBM AMOS 22.0. Based on the ICF framework developed by WHO, health condition was measured by the level of chronic illness; psychological/emotional functions were measured by health satisfaction, self-esteem, and depression; activity capacity was measured by ADLs and IADLs; participation frequency was measured by the total number of social activities joined; formal support was measured by the total number of formal welfare services for people with disabilities utilized; informal support was measured by perceived social support. The findings showed that the level of chronic illness was negatively associated with psychological/emotional functions among the older adults with disabilities. The informal support positively affected psychological/emotional functions and activity capacity, whereas the formal support showed the opposite result. That is, the formal support negatively influenced activity capacity and showed a moderating effect on the association between the level of chronic illness and the psychological/emotional functions in a reverse way. Based on the results, practice and policy implications for alleviating disability level among the older adults with disabilities were discussed.

• Journal of Family Resource Management and Policy Review
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• v.25 no.4
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• pp.87-99
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• 2021

The life of middle-aged one-person households is rising as one of the most important family policy issues in Korean society. In Japan, even in multi-person households, the issues of middle-aged sons and daughters living with their old parents have been a concern. Data are from the 13^th wave of the Korea Welfare Panel Study analyzing 482 middle-aged singe males regardless of their past marital status. The purpose of this study is to investigate the effects of human capital and social capital on the life satisfaction of middle-aged single persons by comparing one-person and multi-person households, respectively. Major results were as follows: First, the level of human capital of one-person households of middle aged males was lower than their counterparts in multi-person households. Second, the level of social capital in the group of divorced or widowed, nonhouseholder middle-aged males in multi-person households was lower than their counterparts in one-person households. Third, the effects of human capital and social capital on life satisfaction was significantly different by their marital status and household types in the group of middle-aged single males. Based on the results, policy implications on the community programs for middle-aged males including not only one-person households but also multi-person households were discussed.