• Tunnel and Underground Space
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• v.24 no.2
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• pp.120-130
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• 2014

Recently, a few mega projects of subsea tunneling are completed or ongoing or under planning stage all across the world. In Korea, subsea tunnels connecting to Japan and China have been considered in the past decades. At the same time, subsea tunnels connecting to domestic islands were planned with preliminary design concepts. Development and improvement of indigenous techniques regarding subsea tunneling are essential in light of current technical level in Korea and their future impact on tunneling industry. In this paper, distinct features of subsea tunnel and construction trend of subaqueous tunnels are analyzed via case studies. Also, case studies about incidents related to subsea tunneling and required techniques to secure safety are presented.

• Korean Journal of Childcare and Education
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• v.14 no.3
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• pp.41-58
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• 2018

Objective: The goal of this study is to research how mother's literacy interaction influences children's interest in vocabulary and reading. Methods: The research subjects selected were 120 children who were three to four-year-old and their mothers. This study conducted questionnaires about the literacy interaction of the mothers. This study also surveyed vocabulary and interest in reading of the children by directly visiting the institutes and by researching the subjects individually. This study used technical statistics, Person's product-moment correlation analysis, and multiple regression analysis in order to analyze the collected data. Results: The results of this study are summarized and concluded as follows. First, open interaction among the sub-areas of a mother's literacy interaction significantly affected children's vocabulary. Second, a mother's literacy interaction with children had no direct impact on the child's interest in reading. Conclusion/Implications: The mother's literacy interaction could have a correlation with the vocabulary development of three to four-year-old children, and a mother's application of open interaction could significantly influence the receptive vocabulary and expressive vocabulary of children.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.1866-1888
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• 2017

Efficient energy consumption in WSN is one of the key design issues for improving network stability period. In this paper, we propose a new Heterogeneity-aware Energy-efficient Clustering (HEC) technique which considers two types of heterogeneity - network lifetime and of sensor nodes. Selection of cluster head nodes is done based on the three network lifetime phases: only advanced nodes are allowed to become cluster heads in the initial phase; in the second active phase all nodes are allowed to participate in cluster head selection process with equal probability, and in the last dying out phase, clustering is relaxed by allowing direct transmission. Simulation-based performance analysis of the proposed technique as compared to other relevant techniques shows that HEC achieves longer stable region, improved throughput, and better energy dissipation owing to judicious consumption of additional energy of advanced nodes. On an average, the improvement observed for stability period over LEACH, SEP, FAIR and HEC- with SEP protocols is around 65%, 30%, 15% and 17% respectively. Further, the scalability of proposed technique is tested by varying the field size and number of sensing nodes. The results obtained are found to be quite optimistic. The impact of energy heterogeneity has also been assessed and it is found to improve the stability period though only upto a certain extent.

• Journal of the Korean housing association
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• v.25 no.2
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• pp.71-78
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• 2014

In recent years, Korean government has focused on improving the environmental impact of products in order to reduce greenhouse gas emissions and to achieve their energy goals. The government has been conducting the following polices such as green procurement inducement and certification system. After carbon labeling was conducted in 2009, among a total of 1,065 items, 97 building materials have been given a certification: finishing materials items have the highest weight (56%). The increase in the certification numbers shows that there has been considerable technical efforts in the building material industry. At the awareness of carbon label and purchase of low carbon product, however, customers are aware of carbon labeling but the purchasing rate of carbon product is low. In this paper, we suggest that low carbon activities must also be considered in order to create client value by adding the concept of ecological efficiency. The objective of this study to measurer the eco-efficiency of carbon labeled building materials on the basis of environmental aspects of the product with the perspective of economy for purchasing the excellent products.

• The Journal of Information Systems
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• v.19 no.1
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• pp.149-177
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• 2010

Radio Frequency Identification(RFID) is rapidly growing the attention of many firms as a care technology for their businesses. As RFID moves into the mainstream, it replaces the standard barcodes that is used to identify and track products for a long time. With the intention of gaining competitive advantages, some firms have started the changeover to RFID technology while others have been disinclined to adopt it. Thus, this study examines firms as an attempt to identify key organizational characteristics driving the ear1y adoption and successful implementation of RFID. Results from 228 adopting organizations show Organizational Needs(Ubiquity and Performance Gaps), Technological Factors(Perceived Benefits and Perceived Cost Savings) and RFID Reduced Risk have a significant influence on RFID initiation. In addition, Trust Factors(Institutional Trusts and Inter-organizational Trusts) have a significant impact on RFID Reduced Risk. Finally, Organizational Readiness(Financial Resources and Technological Knowledge) have a significant influence as moderating effects between RFID initiation and adoption. The implications of the findings propose a new theoretical framework for the future IT/IS adoption study and offer suggestions for RFID researchers and practitioners in the development of the technology.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.11-19
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• 2004

When pile foundation constructed by driving method, it is desirable to perform monitoring and estimation of pile drivability and bearing capacity using some suitable tools. Dynamic Pile Monitoring yields information regarding the hammer, driving system, and pile and soil behaviour that can be used to confirm the assumptions of wave equation analysis. Dynamic Pile Monitoring is performed with the Pile Driving Analyser. The Pile Driving Analyser (PDA) uses wave propagation theory to compute numerous variables that fully describe the condition of the hammer-pile-soil system in real time, following each hammer impact. This approach allows immediate field verification of hammer performance, driving efficiency, and an estimate of pile capacity. The PDA has been used widely as a most effective control method of pile installations. A set of PDA test was performed at the site of Donghea-1 Gas Platform Jacket which is located east of Ulsan. The drilling core sediments of location of jacket subsoil are composed of mud and sand, silt. In this case study, the results of PDA test which was applied to measurement and estimation of large diameter open ended steel pipe pile driven by underwater hydraulic hammer, MHU-800S, at the marine sediments were summarized.

• Asia pacific journal of information systems
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• v.24 no.1
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• pp.65-91
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• 2014

Our study adopted ELM (Elaboration Likelihood Model) to measure the impact of central and peripheral cues on e-healthcare website behavior and its consequence on perceived loyalty of users. While most of ELM studies did not elaborate the antecedent of both central and peripheral cues, we measured the antecedents of those information processing routes to clarify how technical and quality factors (i.e. information organization, security concern, and website attractiveness) develop the nature of either central or peripheral route. We found that information organization was the main antecedent of information quality presented on the website. Second, the results revealed that website security has a positive effect on website credibility. Third, we also found that website attractiveness was positively associated with website credibility. Fourth, consistent with elaboration likelihood model, the empirical findings suggested that information quality (central cue) and website credibility (peripheral cue) were strong predictors of behavior intention to use health website. Our findings also suggested that behavior intention to use health website significantly influenced perceived loyalty.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.5
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• pp.564-569
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• 2011

The current establishment of city gas piping polyethylene (PE) tube used as bonding state or part of the health or safety of fusion is very important. A part of these fusion methods to determine the soundness of the short-term trials and long-term tests can be largely classified. Typical tests include short-term strength, tensile strength, impact strength, compressive strength, resiliency and compression. Polyethylene (PE) pipes installed in the domestic terms of overall penetration rate of 45% has been used. However, polyethylene (PE) pipes have reliability problems, and these occurs mostly in part by defective welding. Therefore, the test is necessary for safety. Non-destructive methods (ultrasonic testing) are difficult to be used. Therefore, Polypropylene copolymer (PP-C), polypropylene homopolymer (PP-H), and polyethylene (PE) pipe are used. Fusion of these materials is necessary in these field however, its technical, and basic research has not been studied well. In this research, short-term strength of welding parts, its tensile strength, hardness, fatigue, and microstructure have been analyzed to find the optimum process conditions to improve mechanical properties.

• Journal of KSNVE
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• v.6 no.6
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• pp.827-834
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• 1996

The effect of pipe breaks in the secondary side is investigated as a part of the fuel assembly qualification program. Using the detailed dynamic analysis of a reactor core, peak responses for the motions induced from pipe breaks are obtained for a detailed core model. The secondary side pipe breaks such as main steam line and economizer feedwater line braksare considered because leak-before-break methodology has provided a technical basis for the elimination of double ended guillotine breaks of all high energy piping systems with a diameter of 10 inches or over in the primary side from the design basis. The dynamic responses such as fuel assembly shear force, bending moment, axial force and displacement, and spacer grid impact loads are carefully investigated. Also, the stress analysis is performed and the effect of the secondary side pipe breaks on the fuel assembly structural integrity under the faulted condition is addressed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.3
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• pp.219-225
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• 2006

Although the round length for tunnel excavation has a major technical and economical impact in conventional tunnelling, there is no coherent procedure available for its determination. In this study, the influence of round length on the behaviour modes of weak rock tunnel was investigated by numerical analyses. Quantitative estimation of the behaviour modes of the face and the unsupported span was established by use of the safety factor for the face stability and the conditional chart. In addition, the optimum round length in the tunnel design stage was investigated based on the detail construction information such as cycle time and material costs. Although this proposed method has some restrictions, it is expected to provide useful information for the optimization of the tunnel excavation, especially in design stage.