• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.79-87
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• 2016

In this paper, concrete base to sleeve connections of hybrid substructures for offshore wind turbines were suggested and investigated experimentally. Punching shear strength tests with well-instrumented three connections under different reinforcement ratios and loading conditions were conducted to investigate the punching shear strength and the behavior of the concrete base to a sleeve connection. The test results showed that the punching strength and stiffness of the connections are affected mainly by the reinforcement ratios. The loading conditions with an axial load and proportional moment cannot affect the stiffness but affect the strength of the connections because of the axial load-moment interaction. The punching shear failure and critical section of the each test specimen are also discussed.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.3
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• pp.123-133
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• 2018

We studied the change process in the design parameters (conditions) of structural sections of vertical/slope breakwaters in Korea over the long term based on an analytical review of the latest design recommendations. This study found the following. 1) Design wave heights have increased gradually with the increase in the wave height of deep sea waves. 2) The relative design wave height ($H_{1/3}/h$) changed from 0.5 in the 1970s to 0.6~0.7 today. This means that design wave heights are overestimated compared with the water depth. 3) Before 1999, the design water level was based on high water during an average spring tide, but this has been increased since 2000 because of additional consideration of anomalous sea levels. 4) Before 1999, the relative crest heights of the investigated breakwaters was 0.6~0.7, but after 1999 this increased to a mean of 1.0 and maximum of 1.26.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.6
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• pp.19-27
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• 2017

This study investigated to predict the compressive strength of unsaturated polyester resin based polymer concrete using the maturity method. The test results show that the development of the compressive strength increased exponentially until an age of 24 hours. After 24 hours, the development of the compressive strength just increased gradually. This test result shows that the strength of unsaturated polyester resin based polymer concrete was developed mainly at the early age. Estimated datum temperature of unsaturated polyester resin based polymer concrete was $-20.67^{\circ}C$ which was much lower than of datum temperature ($-10^{\circ}C$) of Portland cement concrete. Also, this study result shows that the existing maturity index associated with Portland cement concrete was not applicable for polymer concrete because curing time of Portland cement concrete is different clearly with curing time of polymer concrete. The cause of different curing time was that there were different curing mechanisms between Portland cement concrete and polymer concrete. In order to best apply the experimental data to a model, CurveExpert Professional, the commercial software, was used to determine the predictive model regarding the compressive strength of unsaturated polyester resin based polymer concrete. As a result, Gompertz Relation or Weibull Model was an appropriate model as a predictive model. The proposed model can be used to predict the compressive strength, especially, it is more useful when the maturity is in the range between $40^{\circ}C{\cdot}h^{0.4}$ and $900^{\circ}C{\cdot}h^{0.4}$.

• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.3-15
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• 2010

The high-rise building is a dramatic phenomenon and a powerful expression of architecture in the modern civilization. The architecture of these high-rise buildings has been developed with mutual contributions of architectural aesthetic form and advanced technologies. Architecturally the significant evolution of tall buildings from ancient towers is a "change of function" from some religious symbols to a commercial concept that has aesthetically become acceptable with the changing of modern society and culture driven by a technological evolution. Generally, this commercial function in the evolution of high-rise building is office where high-rise working style is simply a necessity to meet quantitative market demands since this style in major cities around world has been changed from low-rise to high-rise during the last several decades in influenced of the modern industrial society. To achieve optimum spaces with architectural aesthetics in the high-rise building, the design has become collaborative, requiring the input of architects, engineers, economists, and other consultants. Hence, architects must deeply understand the basic planning theories of high-rise buildings and try to find optimum planning between architectural aesthetics and other issues. For the approach, we can firstly start with measurement and analysis of the planning use situation for major planning issues of high-rise buildings in practice. Therefore, this study is to analysis Design Elements and to find commonly used planning strategies, tectonic, of high-rise building in practice. It will give a chance to confirm commonly used planning and then becomes the starting point of the planning development of high-rise buildings based on practical planning issues.

• Journal of Ocean Engineering and Technology
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• v.31 no.2
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• pp.130-140
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• 2017

Typically, a submerged breakwater is one of the good scene-friendly coastal structures used to reduce wave energy and coastal erosion. However, sometimes, a submerged breakwater also has a negative aspect in that a strong rip current occurring around an open inlet due to a difference in mean water levels on the front and rear sides of the structure leads to scouring. Such scouring has a bad effect on its stability. In order to eliminate this kind of demerit, this study investigated four new types of submerged breakwaters with drainage channels. First, hydraulic experiments were performed the typical and new structures. Then, the wave height and mean water level distributions around the structures were examined using the experimental results. Finally, it was revealed that the new type of submerged breakwater could efficiently reduce the mean water level on its rear side. In particular, in the case of new-type submerged breakwater 2, an average reduction efficiency of 71.2% for the difference between the mean water levels at the front and rear sides was shown in comparison with the typical one.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.6
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• pp.536-544
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• 2019

Purpose: Proper nutrition is essential for brain development during infancy, contributing to the continued development of cognitive, motor, and socio-emotional skills throughout life. Considering the insufficient published data in the Middle East and North Africa, experts drafted a questionnaire to assess the opinions and knowledge of physicians on the impact of nutrition on brain development and cognition in early life. Methods: The questionnaire consisted of two parts: The first focused on the responders' demographic and professional characteristics and the second questioned the role of nutrition in brain development and cognition. Descriptive statistics were used to summarize respondents' characteristics and their responses to questions. Results: A total of 1,500 questionnaires were distributed; 994 physicians responded. The majority of the surveyed physicians (64.4%) felt that nutrition impacts brain development in early childhood (0-4 years), with almost 90% of physicians agreeing/strongly agreeing that preventing iron, zinc, and iodine deficiency would improve global intelligence quotient. The majority of physicians (83%) agreed that head circumference was the most important measure of brain development. The majority of physicians (68.9%) responded that the period from the last trimester until 18 months postdelivery was crucial for brain growth and neurodevelopment, with 76.8% believing that infants breast-fed by vegan mothers have an increased risk of impaired brain development. Conclusion: The results of this study show that practicing physicians significantly agree that nutrition plays an important role in brain and cognitive development and function in early childhood, particularly during the last trimester until 18 months postdelivery.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.112-117
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• 2005

Geophysical logging is routinely undertaken as part of most coal mine exploration programs. Currently, the main application for the logs is to determine coal seam depth and to qualitatively estimate coal quality, lithology, and rock strength. However, further information can be obtained, if quantitative log interpretation is made. To assist in the uptake of quantitative interpretation, we discuss log responses in terms of the mineralogy of the clastic sedimentary rocks frequently found in the Australian black coal mining areas of the Sydney and Bowen Basins. We find that the log responses can be tied to the mineralogy with reasonable confidence. Ambiguities in the interpretation will be better resolved if a full suite of logs is run. A method for checking for internal consistency, by comparing calculated and observed velocities, is also described. A key driver for quantitative interpretation is geotechnical characterisation. We propose a classification system for clastic rocks that takes into consideration physical rock properties that can be inferred from geophysical logs.

• Journal of the Korean Society of School Health
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• v.30 no.3
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• pp.211-223
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• 2017

Purpose: The purpose of this study is to clarify the social stigma phenomenon in teachers' perceptions and attitudes toward students who are classified as mental health support needs students in middle and high schools. Methods: Qualitative research was conducted through in-depth interviews and observations of 17 teachers and 2 consultants from 2 middle and high schools in Green City, which were evaluated as successful among the six pilot project schools designated by the Ministry of Education in 2013. The study's analysis is based on Hatch's hermeneutical method. Common categories were developed from the interviews and observations. Then, inferences were made per category and given importance to draw conclusions and lessons. Results: Teachers had a strong stigma in their perceptions of and attitudes to special needs students. Their perception was that those students are bound to go wrong due to family problems, even some having difficulty breathing, and that it's beyond their limit to help them. In addition, their attitudes included stereotypes, favoritism, punishment, and referral to experts. As a result, teachers did not expect those students would be cured or change and showed passive attitudes while shifting the responsibility to families and experts. Conclusion: This study is meaningful in that it showed the limitations of the role of teachers regarding mental health support needs students from the perspective of the teachers themselves. Today, when students' mental health problems are emerging as a serious issue, it is necessary to provide support to improve teacher's awareness and capabilities regarding adolescent mental health problems. In addition, we suggest the current selective policy that sorts out special needs students and provides care for them to evolve into a universal policy that improves public awareness and focus on prevention.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.203-208
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• 2021

This study is to investigate the impact of emotional intelligence of online shopping mall call center counselor on customer orientation. The SPSS 25.0 ststistics program was applied for the empirical analysis 148(87.05%)of 170 copies are used for final data analysis. The implications of results are as follows. First, use of emotion, a subfactor of emotional Intelligence, has shown to have a significant positive effect on customer orientation. Second, other's emotional appraisal, a subfactor of emotional Intelligence, has shown to have a significant positive effect on customer orientation. Third, self emotional appraisal, a subfactor of emotional Intelligence, has shown to have a significant positive effect on customer orientation. Fourth, regulation of emotion, a subfactor of emotional Intelligence, has shown to have a significant positive effect on customer orientation.

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.367-380
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• 2021

This study evaluated the stability through a three-dimensional numerical analysis method when a natural cave exists under a road in operation in Jeju Island. In order to confirm the geometric and geotechnical characteristics of the Jeju natural cave passing under the road, existing geotechnical survey reports were collected, and were studied the characteristics. In order to evaluate the effect of vehicle vibration loading on the natural cave in Jeju, three-dimensional numerical analysis was performed considering discontinuities. Through this, the stability of roads and caves with respect to vehicle speed and the depth of cover (distance from the road to the top of the natural cave) was evaluated and countermeasures were suggested. In order to secure the long-term stability of the Jeju natural cave that penetrates the lower part of the road, it was evaluated that systematic management such as long-term measurement management, reinforcement measures, and emergency measures would be necessary depending on the depth of the cover.