• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.245-254
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• 2018

The purpose of this study is to review the relationship between psychological capital and organizational commitment/ innovative behavior, and the moderating effect of organizational support. In order to verify and achieve the purposes mentioned above, questionnaire data were gathered and analysed from 315 professors and teachers of Korea Politechnics Colleges. Multiple regression and multiple hierarchical regression analysis were applied to test the proposed hypotheses: 1) the relationship between psychological capital and organizational commitment, 2) the relationship between psychological capital and innovative behavior, 3) the moderating effect of organizational support on the relationship between psychological capital and organizational commitment, 4) the moderating effect of organizational support on the relationship between psychological capital and innovative behavior. Empirical survey's findings are as follows; First, self-efficacy and optimism appeared to be positively related with organizational commitment, and all psychological capital factors(self-efficacy, resilience and optimism) appeared to be positively related with innovative behavior. Second, organizational support appeared to have moderating effect partly on the relationship between psychological capital and organizational commitment, but it did not have a moderating effect on the relationship between psychological capital and innovative behavior. Self-efficacy and optimism appeared to be more positively related with organizational commitment in higher organizational support situation than in lower organizational support situation.

• Journal of Korea Water Resources Association
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• v.51 no.11
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• pp.977-987
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• 2018

The purpose of the water distribution system is gradually changing to increase the flexibility for responding to various abnormal situations. In addition, it is essential to improve resilience through preparing emergency plans against water supply failure. The most efficient way is emergency interconnections which supply water from interconnected adjacent blocks. To operate successful interconnections, it is essential to evaluate the supply performance in spatial and temporal aspects. The spatial and temporal aspects are dominated by its interconnected pipes and interconnected reservoirs respectively. In this study, an emergency interconnection scenario where problem occurred in reservoir 1 at 0:00hr in A city, Korea. An Advanced-Pressure Driven Analysis model was used to simulate the volume and inflow volume of the interconnected reservoirs. Based on the hydraulic analysis results, a multi-dimensional evaluation of the supply performance was conducted by applying possible water supply range indicator (PWSRI) and possible water supply temporal indicator (PWSTI) which are based on fuzzy membership functions. As a result, it was possible to evaluate the supply performance on the sides of consumers in spatio-temporal aspects and to review whether established plans mitigate the damage as intended. It is expected to be used for decision making on structural and non-structural emergency plan to improve the performance of an emergency interconnection.

• Korean Journal of Medicinal Crop Science
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• v.22 no.6
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• pp.497-503
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• 2014

In order to produce the high quality of dried-ear mushroom, various drying methods such as hot-air drying at $40{\sim}80^{\circ}C$, freeze drying and drying in vinyl house were carried out. Drying hours of hot-air drying, freeze drying and drying in vinyl house were 12.5~21.5, 36.0 and 72.0 hrs, respectively. Vitamin $D_2$ content of sample was the highest as $6.77{\mu}g/g$ DW in drying in vinyl house and then followed by freeze drying as $5.90{\mu}g/g$ DW and hot-air drying as $1.89{\sim}5.01{\mu}g/g$ DW. After dry, external appearance and color of mushrooms applied hot-air drying and drying in vinyl house were better than freeze-dried one. After rehydration, water uptake of sample in drying in vinyl house and hot-air drying at $50{\sim}60^{\circ}C$ were 17.8 and 19.3~21.0 times, respectively. The methods of drying in vinyl house and hot-air drying at $50{\sim}60^{\circ}C$ also led to high hardness, good shape and resilience. As the results of production of dried-ear mushroom with high quality, we suggest that the best method for drying is the drying in vinyl house due to not only high vitamin $D_2$ content, good external appearance and color after drying but also high hardness and good shape after rehydration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1632-1640
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• 2014

This study was conducted to investigate the factors affecting smartphone addiction of university students and to provide the data for developing intervention program of smartphone addiction prevention. The data were collected from 354 university students and analyzed with t-test and multiple regression by using SPSS 18.0 program. The smartphone addiction rate was 27.4%, which the high risk group rate was 6.2% and potential risk group rate was 21.2%. The significant factors of smartphone addiction were gender(${\beta}=0.149$, p<.001), average daily using time in week(${\beta}=0.292$, p=.001), average daily using time in weekend(${\beta}=0.390$, p<.001), wrist pain in using smartphone(${\beta}=0.148$, p<.001), accident in using smartphone(${\beta}=0.133$, p=.002), sociality(${\beta}=-0.099$, p=.029), impulsiveness(${\beta}=0.211$, p<.001), SNS addiction(${\beta}=0.376$, p<.001). And these factors explained 43.3% of the variance in smartphone addiction. In conclusion, the results from this study indicated a need to develop the intervention program to prevent smartphone addiction considering these factors affecting smartphone addiction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.238-250
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• 2020

This study investigated the long-term measures to minimize flood damage in the event of flooding in urban areas. The relationship between urban spatial factors and the impact of flood damage was analyzed, focusing on non-structural measures. The urban spatial factors were categorized into three parts: open space, disaster prevention facilities, and urbanization sectors. Multiple regression analysis was used to investigate how urban spatial factors influence flood damage. As a result of the analysis, the crucial factors, such as the reduced green areas and parks included in the open space sectors, resulted in an increased flood damage potential. The posterior factors, such as the population density and GRDP included in the urbanization sector concurrently led to an increase in the flood damage potential. Therefore, to better adapt to climate change, it is necessary to establish urban spatial plans strategically, such as green areas and parks. Meanwhile, the population density and GRDP are also the main factors causing flood damage. Therefore, when used appropriately in terms of resilience, it will serve as adaptations and recovery.

• Journal of the Korean association of regional geographers
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• v.21 no.4
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• pp.751-763
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• 2015

Both the selection of indicators and weights for them are critical issues in the vulnerability assessment. This study is to assess the air pollution vulnerability focused on ozone for 249 local jurisdictions using weights calculated by the entropy methodology and then examine the applicability of the methodology. We selected indicators for air pollution vulnerability assessment and standardized them. Subsequently, we calculated weights of each indicator using the entropy method and then integrated them into the vulnerability index. The exposure indicators consider meteorological and air pollution factors and the sensitivity of the local jurisdiction include variables on vulnerable areas and environments. The adaptive capacity contains socio-economic characteristics, health care capacities and air pollution managemental factors. The results show that Hwaseong-si, Gwangjin-gu, Gimpo-si, Gwangju-si, Gunpo-si are among the highest vulnerabilities based on the simple aggregation of indicators. And vulnerability-resilience (VRI) aggregation results indicates the similar spatial pattern with the simple aggregation outcomes. This article extends current climate change vulnerability assessment studies by adopting the entropy method to evaluate relative usefulness of data. In addition, the results can be used for developing customized adaptation policies for each jurisdiction reflecting vulnerable aspects.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2A
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• pp.65-73
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• 2012

In this study, we tested structural performance of Half-Decked PSC girder which was developed for applying to long span bridge. We operated 4 point bending test with 60 m span full scale girder designed as simple bridge with hinge-roller boundary condition. Actuators were set on the both sides of girder, 5.5 m away from the center, and 4 stages of cyclic loading was applied at rate of 1 kN/sec. Through stages 1 to 4, loading and unloading 1,000 kN, 1,200 kN, 1,500 kN, and 2,000 kN were repeated and displacement, strain of concrete and steel, crack of girder were checked. From these results, the strength of girder was assessed and resilience and ductility were observed after removing the load. Since initial flexural crack occurred in the vicinity of 1,400 kN, non-linearity of load-displacement curve appeared and definite residual strain was measured at that point. The test result showed that initial cracking load was over twice the DB-24 load which means the developed girder had sufficient strength. To verify the experimental results, we numerically analyze the test and confirmed that the data were similar with results from the test above. Half-Decked PSC type of 60 m-girder developed in this study showed its adequate structural capacity through static loading test, which proved that possibility of applying the girder to actual bridges practically.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.311-317
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• 2017

The aim of this study is to investigate the environmental properties of paddy soils depending on farming methods and seasonal variation. The paddy soils in 11 plots of conventional paddy and 24 plots of organic paddy were sampled and analyzed in four season of March, May, August, and October. The obtained data of soil properties were used for statistical analysis. Analysis of variance showed that only $NH_4-N$ and $P_2O_5$ were significantly different depending on farming methods. However, the differences of all soil properties depending on seasonal variation were strongly significant. Principal component analysis also presented that nitrogen and phosphorus concentration in soils were more significantly influenced by seasonal variation than farming method. Electric conductivity in soil was decreased from March to October. Amounts of soil organic matter in August and October were higher than that in March and May. T-N was decreased from March to October. $NH_4-N$ and $NO_3-N$ in the soil of both conventional and organic paddy were higher in May than other seasons. T-P concentration was found to be highest in August, but $P_2O_5$ concentration was lowest in August. It can be concluded that seasonal variation should be considered for analysis and comparison of soil environmental properties.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.71-81
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• 2020

In Korea, more than 70% of the ammonia(NH₃) released into the atmosphere is known to originate from livestock manure. The total emission (kg year^-1) is calculated by multiplying the emission factor (kg head^-1 yr^-1) and the activity data (head). To improve the accuracy and reliability of the NH₃ emission estimation process, an accurate account of livestock manure production, calculation of NH₃ conversion and generation during the composting and liquefaction of manure, estimation of NH₃ generation in the storage and transportation of manure and compost, and a comparative study of NH₃ emission during the soil spreading process must be performed. Compared to the US and EU-28, in particular, the domestic emission factor is relatively even and the spatial/temporal scale is not broken down sufficiently to reflect the domestic situation. As a way to improve the accuracy and expertise of estimating NH₃ emission factors, a 'dynamic chamber-capture system' can be utilized, which allows complex considerations of compost, liquid manure, soil, and climate characteristics. By reviewing and comparing the data related to domestic and foreign NH₃ emission, we identified shortcomings in the current domestic system and the directions to be taken and suggested a chamber system that could estimate NH₃ emission flux. It is also necessary to establish a methodology for mesocosm systems in the field, in addition to indoor chamber systems, to be linked with practical policies, such as the calculation of new emission factors for missing sources.

• Ecology and Resilient Infrastructure
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• v.3 no.2
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• pp.117-125
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• 2016

Current cities encounter various types of water problems due to rapid urbanization and climate change. The increasing significance of urban water problems calls for the establishment of resilient alternatives to prevent and minimize social loss that results from these phenomena. As a background research for establishing resilient infrastructures for the mitigation of urban water problems, we evaluated the robustness of structural alternatives for urban flood as a representative case. Combining the robustness index (RI) and the cost index (CI), we suggested the robustness-cost index (RCI) as an indicator of the robustness of structural alternatives, and applied the index to assess the existing infrastructures and structural alternatives (i.e., sewer network expansion, additional storage tank construction, and green roof construction) at a site prone to floods located around Gangnam-station, Seoul, Korea. At a rainfall intensity frequency range of 2 to 20 years, the usage of a storage tank and a green roof showed relatively high RCI value, with a variation of an alternative showing greater RCI between the two depending on the size of design rainfall. For a rainfall intensity frequency of 30 years, installing a storage tank with some green roofing was the most resilient alternative based on the RCI value. We proposed strategies for establishing resilient infrastructures for the mitigation of urban floods by evaluating the robustness of existing infrastructures and selecting optimal structural alternatives with the consideration of scales of design disaster.