• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.443-454
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• 2020

The purpose of this study is to propose a structural theoretical model that can explain the learning flow of online distance education participants and to clarify the structural causal relationship among related variables that affect the learning flow of cyber university learners. Study results found a modified final model with a statistically significant fit based on the structural research model proposed in this study explained the learning flow of cyber university learners. Second, as a result of verifying the relationship between learning motivation and learning flow of cyber university learners, it was found that intrinsic motivation had a significant positive effect on learning flow. Third, as a result of the empirical verification on the relationship between academic self-efficacy and learning flow of cyber university learners, it was found that academic self-efficacy had a significant effect on learning flow. Fourth, as a result of empirical verification on the relationship between self-directed learning and the learning flow of cyber university learners, it was found that the learner's self-directed learning ability had a significant effect on learning flow. Such research results can be used to suggest a strategic direction for successful settlement and diffusion of a new paradigm of online non-face-to-face distance education, which has recently attracted attention.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.389-403
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• 2011

The objective of this study is to find out how strategic human resource management(SHRM) of a facility security firm affects its organizational culture and behaviors of its members. This study was executed in June 2010 with facility security officers(FSO) in four private security firms by using a judgment sampling technique. A total of 343 FSOs were used in final analysis. Coefficient of reliability(Cronbach's coefficient alpha) of the survey was 0.691. The conclusion was as follows: First, SHRM of facility security firms exert its influence on organizational culture. That is, promotion of education/training, compensation, making avid followers, and career development may facilitate settlement of hierarchical, development-oriented, agreement -based and rationality-oriented culture. Second, SHRM of security firms would affect organizational citizenship behaviors(OCB), i.e., the promotion of education/training, compensation, making avid followers, and career development would tend to enhance consideration for others and altruistic, participatory, conscientious and gentlemanly behaviors. On the other hand, if proper compensation is not made, above-mentioned behaviors would decrease. Third, organizational culture of security firms tends to affect OCB. That is, when hierarchical, development-oriented, agreement-based and rationality-oriented culture is settled, consideration for others, altruistic, participatory, conscientious and gentlemanly behaviors tends to be enhanced.

• Journal of Technology Innovation
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• v.24 no.4
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• pp.221-248
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• 2016

In this study, we conducted an in-depth literature review of the innovation characteristics of nuclear technology. We understood that the main issue may be a transition of fourth generation nuclear energy technology. We also analyzed a present status of Korean policy on nuclear energy technology and identified some implications for a successful settlement of the fourth generation nuclear energy technology. This study could provide some policy implications for maintaining the sustainable competitiveness of the fourth generation nuclear energy technology in Korea. According to our study, the factors that influence on a transition of nuclear energy technology are a policy-induced market for technical application and demonstration, stable and long-term resource allocation, constant interaction among stakeholders of innovation, accumulation of skill and know-how for an entire system. In addition, we conducted a case analysis on policy for Korean fourth generation nuclear energy technology. According to this case study, it would be necessary for Korea to pursue systematic training of human resources, active response to a social acceptance and reaction, establishment of specific plan for technical demonstration, long-term policy suggestion, and active promotion of constant interaction between stakeholders.

• The Journal of Engineering Geology
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• v.25 no.1
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• pp.115-129
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• 2015

The cut-slope of a large-sectional tunnel portal is recognized as a potential area of weakness due to unstable stress distribution and possible permanent displacement. This paper presents a case study of a slope failure and remediation for a large-scale cut-slope at a tunnel portal. Extensive rock-slope brittle failure occurred along discontinuities in the rock mass after 46 mm of rainfall, which caused instability of the upper part of the cut-slope. Based on a geological survey and face mapping, the reason for failure is believed to be the presence of thin clay fill in discontinuities in the weathered rock mass and consequent saturationinduced joint weakening. The granite-gneiss rock mass has a high content of alkali-feldspar, indicating a vulnerability to weathering. Immediately before the slope failure, a sharp increase in displacement rate was indicated by settlement-time histories, and this observation can contribute to the safety management criteria for slope stability. In this case study, emergency remediation was performed to prevent further hazard and to facilitate reconstruction, and counterweight fill and concrete filling of voids were successfully applied. For ultimate remediation, the grid anchor-blocks were used for slope stabilization, and additional rock bolts and grouting were applied inside the tunnel. Limit-equilibrium slope stability analysis and analyses of strereographic projections confirmed the instability of the original slope and the effectiveness of reinforcing methods. After the application of reinforcing measures, instrumental monitoring indicated that the slope and the tunnel remained stable. This case study is expected to serve as a valuable reference for similar engineering cases of large-sectional slope stability.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.460-470
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• 2017

Mussels are major fouling organisms causing serious technical and economic problems. In this study, antifouling activity towards mussel was found in three compounds isolated from a marine bacterium associated with the sea anemone Haliplanella sp. This bacterial strain, called PE2, was identified as Vibrio alginolyticus using morphology, biochemical tests, and phylogenetic analysis based on sequences of 16S rRNA and four housekeeping genes (rpoD, gyrB, rctB, and toxR). Three small-molecule compounds (indole, 3-formylindole, and cyclo (Pro-Leu)) were purified from the ethyl acetate extract of V. alginolyticus PE2 using column chromatography techniques. They all significantly inhibited byssal thread production of the green mussel Perna viridis, with $EC_{50}$ values of $24.45{\mu}g/ml$ for indole, $50.07{\mu}g/ml$ for 3-formylindole, and $49.24{\mu}g/ml$ for cyclo (Pro-Leu). Previous research on the antifouling activity of metabolites from marine bacteria towards mussels is scarce. Indole, 3-formylindole and cyclo (Pro-Leu) also exhibited antifouling activity against settlement of the barnacle Balanus albicostatus ($EC_{50}$ values of 8.84, 0.43, and $11.35{\mu}g/ml$, respectively) and the marine bacterium Pseudomonas sp. ($EC_{50}$ values of 42.68, 69.68, and $39.05{\mu}g/ml$, respectively). These results suggested that the three compounds are potentially useful for environmentally friendly mussel control and/or the development of new antifouling additives that are effective against several biofoulers.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.2
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• pp.151-163
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• 2006

Although various methods for effective modeling of pre-reinforced zones have been suggested for numerical analysis of large section tunnels, tunnel designers refer to empirical cases and literature reviews rather than engineering methods because ones who use commercial programs are unfamiliar with a macro-scale approach in general. Therefore, this paper suggests a simple micro-scale approach combined with the macro-scale approach to determine equivalent design parameters for effective numerical modeling of pre-reinforced zones in tunnel. This new approach is to determine the equivalent stiffness of pre-reinforced zones with combination of ground, bulb, and steel in series or/and parallel. For verification, 3-D numerical results from the suggested approach are compared with those of a realistic model. The comparison suggests that two cases make best approximation to a realistic solution: One is related to the series-parallel stiffness system (hereafter SPSS) in which bulb and steel are coupled in parallel and then connected to the ground in series, and the other is the series stiffness system (hereafter SSS) in which only bulb and steel are coupled in series. The SPSS is recommended for stiffness calculation of pre-reinforced zones because the SSS is inconvenient and time-consuming. The SPSS provides slightly bigger vertical displacement at tunnel crown in weathered rock than other cases and give almost identical results to a realistic model for horizontal displacement at tunnel spring line and ground surface settlement. Displacement trends on weathered rock and weathered soil are similar. The SPSS which is suggested in this paper represents the behavior mechanism of pre-reinforced area effectively.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.2
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• pp.143-154
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• 2016

This study investigated the occurrences, causes, and mitigation of the recent ground subsidence and underground cavity generation events in Korea. Two main causes of ground subsidence are (1) the soil erosion by seepage during tunneling and earth excavation and (2) the damage of underground pipes. The main cause of the soil erosion during tunneling was the uncontrolled groundwater flow. Especially, when excavating soft grounds using a tunnel boring machine (TBM), the ground near TBM operation halt points were found to be the most vulnerable to failure. The damage of underground pipes was mainly caused by poor construction, material deterioration, and differential settlement in soft soils. The ground subsidence during tunneling and earth excavation can be managed by monitoring the outflow of groundwater and eroded soils in construction sites. It is expected that the ground subsidence by the underground pipe damage can be managed or mitigated by life cycle analysis and maintenance of the buried pipes, and by controlling the earth pressure distribution or increasing the bearing capacity at the upper ground of the buried pipes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.545-552
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• 2017

Ground subsidence can result in the formation of sinkholes, potholes, settlement of structures, and road subsidence. Road subsidence is described as the sudden collapse of the road surface into subsurface cavities caused by the loss of bearing capacity in the ground, such as the dissolution of limestone by fluid flow in the surface causing the formation of voids leading to subsidence at the surface. Road subsidence occurs about 665 times annually, and this incidence has been increasing until 2013. Damaged underground facilities, management negligence, and lowering of the ground water table have been the causes of road subsidence in Seoul. Seoul metropolitan government announced special management counter plans to relieve the anxieties and make the roads safe for passing. Construction sites, such as excavation works, need to be managed properly because they have strong potential to induce road subsidence. The aim of this study was to identify the main causes of road subsidence and suggest management plans. First, life cycle cost analysis revealed the daytime construction to be more appropriate than nighttime. In addition, by analyzing the limitations of using sand as a backfill material, it is proposed to use a flowable backfill material instead of sand. Finally, to reduce the blind spots, which is a problem in surveying the road pavement conditions of local governments, the road to be managed is divided into several zones, and a specialized agency is selected for each zone and a method of surveying the blind spots through collaboration is suggested.

• Journal of Information Technology Services
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• v.13 no.2
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• pp.219-250
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• 2014

Corporations look for their competitiveness in many different areas, and one of them is customer call center, which provides professional, special service to the customers. The importance and the value of realization of customer satisfaction at each call center have become significant as it plays a leading role and is responsible for customer recreation and follow-up services. This study held in-depth interviews with 3 groups of professional call representatives (categorized by experience) from popular property and life insurance companies in Korea who operate in and outbound calls. Three variables, emotional quotient, organizational citizenship behavior (OCB), and IT utilization skill, were selected and it was observed how these variables affect the job performance of in and outbound call center representatives. The importance of the relationship between the variables and the key factors in the future direction of improvement of the call center representative organization was analyzed. Emotional quotient refers to the ability to recognize and use the emotion of oneself and others. It was considered it would be effective in enhancing the counseling ability of call center representatives, This study identifies the effect of emotional quotient on job performance and organizational citizenship behavior, which is defined as actions outside of normative roles in the organization. Also, the study aims to prove the effect of emotional quotient on the rapidly developing IT utilization ability in relation to job performance. As a result, it was found that service career (3 months, 3 years, 10 years) had a significant effect on the key factors that affect the organization-emotional quotient, IT utilization skill, and OCB. Especially for OCB, it was considered relatively less important to the new employees, while it greatly affected the job performance, rate of settlement, and sustainment of the working life for those with longer experience. Also, the result of the interview for each variable differed by the service career. Emotional quotient, IT utilization skill, and OCB were close connection for the representatives with longer experience than for those with shorter experience. And the level of intimacy of their relationship with job performance was in proportion to the years of service. Thus, to secure stability for the call center representatives and enhance their job performance continually, the importance of emotional quotient and IT utilization skill shall be reflected in the operation process actively. In particular, in order to lead a organization with outstanding culture, a management system shall apply OCB from the recruitment process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.600-608
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• 2017

The presence of piping in a levee body allows water seepage to occur by producing a large cavity or water tunnel within it, ultimately resulting in the failure of the river levee and differential settlement. In order to properly cope with river levee failure due to piping and establish a proper remediation method for this problem, it is necessary to analyze the failure mechanism of the river levee due to piping. Therefore, this study analyzed the shape and mechanism of river levee failure due to piping through small-scale and large-scale models and evaluated the seepage pressure distribution characteristics in the hydraulic well, which has been suggested as a remediation method for piping. According to the results of this study, as the safety factor for the piping in the river levee decreased, the river levee failure shape was more clearly shown through the small-scale model test. In the large-scale model test, the type of local damage to the levee due to the piping was identified and the evaluation showed that the hydraulic well had the largest effect on the inhibition of piping below the center of the well. A follow-up study is needed to confirm the reliability of the results. However, it is thought that this study can be utilized as the baseline data for research into the piping-induced river levee failure mechanism and for the preparation of a remediation method.