• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.170-177
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• 2005

This study was conducted in order to assess whether the form of the shade guide affects in deciding the color of the teeth using the shade guide Eight shade light cured composite resins (Esthet-X, Dentsply, Milford, USA) were used in this study. Shade guides including the model of maxillary central incisors, teeth-form shade guide, doughnut form shade guide, and shade guide with perforated gray shield were prepared with eight shade composite resins and provided the codes randomly After arranging the models of teeth, 19 dentists working at the clinic of the Dentistry of Chonnam University Hospital and 65 students of college of dentistry, Chonnnam University selected the shade guides corresponding to the color of each tooth on the gray board under the D$_{65}$ standard illuminant. Bl shade showed highest accuracy of about 95% among all shade guides of 3 forms applied to the test and regardless of observer, tooth form shade guide showed the highest accuracy (p < 0.05) , and the doughnut form showed the lowest accuracy (p < 0.05). At the time of deciding on the color of the teeth using the shade guides as a result of above, the forms of the shade guides can affect the accuracy, and it suggests that the development of the diversified forms of shade guides, which may obtain more accurate results, is required.

• 한국노년학
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• v.37 no.4
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• pp.909-924
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• 2017

The purpose of this study was to identify the impact of chewing ability on cognitive function of older people in Korea and the mediation effect of physical function and depression using the nationwide data from "Survey of the Living Conditions and Welfare Needs of Korean Older Persons in 2014", in Korea. This study was conducted on a total of 10,451 respondents in the "Survey of the Living Conditions and Welfare Needs of Korean Older Persons in 2014" and the data collection period was from June 11, to September 4, 2014. Chewing ability was used in the scale on level of daily life inconvenience in chewing ability (meat or hardness). Cognitive function was measured using MMSE-DS, physical function using K-IADL, and depression using SGDS-K. The data were analyzed using the SPSS 24.0 program and Process Macro. Total effects of chewing ability on cognitive function were not significant(p>.05). Direct effects of chewing ability on cognitive function were not significant(p>.05). There were the dual mediation effect(p<.05) of physical function and depression, a complete mediating effect by physical function(p<.05) or depression(p<.05) in the impact of chewing ability on cognitive function of older people in Korea. These results indicate that physical function and depression effect directly and indirectly in the impact of chewing ability on cognitive function of older people. In conclusion, it is suggested that to prevent the decline of cognitive function in older people, it is necessary to consider not only nursing strategies for strengthening chewing ability and physical function, but also nursing interventions for relieving or preventing depression in older people.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.181-189
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• 2021

This study uses a structural equation model for the turnover intention of female nurses performing shift work at a tertiary hospital. Data collection was conducted from November 11 to December 20, 2015, and 283 samples were included in the final analysis. As a result, 12 of the 19 hypotheses of the final model were supported. It was confirmed that external employment opportunities, nursing professional value, nursing organizational culture, job stress, job satisfaction, organizational commitment, and burn out accounted for 47.8% of the turnover intention. Burn out(+) and organizational commitment(-)had direct effects on turnover intentions, and nursing professional, relationship-oriented nursing organizational culture, and job stress showed indirect effects. Therefore, in order to reduce the turnover intention of female nurses working in shifts at tertiary hospitals, it is necessary to prevent burnout, increase organizational commitment, and job satisfaction. For this purpose, measures to strengthen relation-oriented nursing organizational culture and nursing professional intuition are required. In terms of hospital manpower management, the institutional arrangements of hospitals that enable flexible working hours adjustment, mutually respectful relationship-centered organizational culture, education, and policy support to reinforce nursing professional intuition, and the institutional system of hospitals to work with pride should be implemented.

• Journal of the Korean Society for Library and Information Science
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• v.55 no.3
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• pp.17-56
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• 2021

The purpose of this study was to focus on the discussion on the introduction of the librarian qualification certification system, which is being discussed as a way to raise the qualification level of experts as a system for expert certification and to raise social awareness as experts. First, the introduction of the library and information science curriculum certification system was discussed. Second, the issues to be considered when introducing the certification system were discussed. In other words, we analyzed in depth what matters we should consider when discussing the certification system. Third, the components of domestic and overseas certification systems were investigated and analyzed, and measures applicable to the librarian qualification certification system were discussed. Fourth, it was proposed to introduce a certification system for the Department of Library and Information Science. Also, based on the results of the analysis, it was suggested what could be a problem when introducing the certification system to the Department of Library and Information Science in Korea and what contents should be reviewed. In this study, in order to propose the introduction of the librarian qualification certification system, the purpose of the librarian qualification certification system, the certification criteria, the certification institution, and the contrast between the university and the Department of Library and Information Science were also dealt with in detail.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.383-390
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• 2021

The experiments in coastal engineering are very complex and a lot of components should be concerned. The experience has an important role in the successful execution. Hydraulic model experiments have been improved with the development of the wave generator and the advanced measuring apparatus. The hydraulic experiments have the advantage, that is, the stability of coastal structures and the hydraulic characteristics could be observed more intuitively rather than the numerical modelings. However, different experimental results can be drawn depending on the model scale, facilities, apparatus, and experimenters. In this study, two-dimensional hydraulic experiments were performed to suggest the guide of the test wave(random wave) generation, which is the most basic and important factor for the model test. The techniques for generating the random waves with frequency energy spectrum and the range for the incident wave height [(H_S)_M/(H_S)_T = 1~1.05] were suggested. The proposed guide for the test wave generation will contribute to enhancing the reliability of the experimental results in coastal engineering.

• Land and Housing Review
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• v.13 no.1
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• pp.131-140
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• 2022

A smart window is a new building material that can realize energy savings in a building. Smart windows can freely adjust Visible Light Transmittance (VLT) and solar gain coefficient (g-value) according to the situation. Smart windows include such technologies as Electrochromic (EC), Suspended Particle Device (SPD), and Polymer Dispersed Liquid Crystal (PDLC). Recent research on building energy savings through the VLT and g-value control functions of smart windows is being actively conducted and meaningful results are being drawn. However, since most of the research is focused on energy savings, research on the indoor environment is somewhat lacking. A building is a space where people live and the comfort of life should be prioritized before energy savings. Therefore, in this study, analysis on the daylight performance of an office space was carried out. Through green building standards such as LEED, BREEAM, CASBEE, and G-SEED, the daylight performance was reviewed according to VLT value changes of the smart window. In addition, a study was conducted on the VLT range of the electrochromic façade that can maintain a comfortable indoor environment. The smart window used electrochromic control with a wide range of VLT. The study showed that the minimum VLT of a smart window that can satisfy G-SEED is 25% or more. In addition, it was found that the VLT change of the electrochromic smart window did not significantly affect the uniformity of the room. When the LEED standard was applied, the minimum VLT value of the electrochromic smart window that must be maintained according to each orientation of the building was derived.

• Journal of Science Education
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• v.47 no.2
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• pp.127-138
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• 2023

In this study, the implementation of science classes by pre-service elementary teachers were explored to foster the digital literacy of elementary students. To this end, interviews were conducted with four university students in their 4th year of study at 'G' Education University in Gwangju, also their teaching plans and class implementation videos were analyzed. Interview questions were divided into the science class planning stage, the science class implementation stage, and the post-science class implementation stage, and the interview contents were transcribed and categorized after recording. The results of the study are as follows. First, in the science class planning stage, pre-service elementary teachers considered the degree of elementary students' familiarity when choosing digital teaching and learning tools to foster digital literacy. While writing the teaching plan, it was difficult to set standards related to fostering digital literacy. Second, while pre-service elementary teachers had positive experiences such as improving students' participation in classes and increasing student-specific guidance through real-time data sharing, class time was exceeded due to poor use of digital teaching and learning tools. Third, after teaching their science classes, pre-service teachers presented reflections and requirements for the class. Based on these results, the necessity of developing digital literacy for pre-service elementary teachers and the need to improve the curriculum of education university were proposed.

• Journal of the Korean Geotechnical Society
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• v.26 no.3
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• pp.5-12
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• 2010

In this study, in order to clarify the effect of the direction of cyclic shear on the post-earthquake settlement the multi-directional shear tests were carried out for Toyoura Japan standard sand, Genkai natural sand, Kaolinite and the Granulated Blast Furnace Slag (GBFS). The diameter and the height of the specimen are 75 mm and 20 mm, respectively. In a series of tests, the number of strain cycles was adjusted as n=5, 20, 30, 100, 200 and the shear strain amplitudes were varied from 0.1% to 1.0%. The relative densities of each samples were also adjusted as Dr=50, 60 and 70%. From the test results for Toyoura sand and GBFS, it is clarified that the post-earthquake settlement is relatively large at the small relative density and becomes large with the shear strain amplitude. When the influence of difference on the direction of cyclic shear decreases, the post-earthquake settlement strain for Toyoura sand is converged to a constant value, but the GBFS increases with the number of strain cycles. In addition, the post-earthquake settlement is in the order of Kaolinite > Toyoura sand > Genkai sand > GBFS.

• Journal of the Korean Geotechnical Society
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• v.24 no.5
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• pp.107-115
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• 2008

This paper is performed to examine the effect of creep during the primary consolidation and the applicability of the Yin's EVP (Elasto-Visco-Plastic) model. In ordinary consolidation theories using the elastic model, the primary consolidation process can be expressed but the secondary consolidation process cannot. It is due to the viscosity, which can express the secondary consolidation, and is sometimes related to the scale effect (difference of the thickness of clay layer between laboratory sample and field condition) such as hypotheses Type A and Type B shown by Ladd et al. (1977). Usually, the existence of the creep during the primary consolidation has been conformed and the Type B is well acceped. On the other hand, from the large-scaled consolidation tests the intermediate characteristic between Type A and Type B was proposed as Type C by Aboshi (1973). In this study, to clarify the effect of creep on the settlement-time relation during the primary consolidation in detail, Type B consolidation tests were performed using the separate-type consolidation test apparatus for a peat and clay. Then the test results were analyzed by using Yin's EVP Model (Yin and Graham, 1994). In conclusion, followings were obtained. At the end of primary consolidation, the compression for the subspecimens should not be the same because of the difference of the excess pore water pressure dissipation rate. And the average settlement measured by the separate-type consolidometer coincides with the analyzed one using the Yin's EVP model. As for the dissipation of the excess pore water pressure, however, the measured excess pore water pressure dissipates faster compared with the Yin's model.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.177-191
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• 2011

This paper describes a dune field on shoreline of Young Gwang. To clarify geomorphic characteristics, made an analysis of grain size of the sand sediments samples and surface texture of quartz grains, and field survey. The following results were obtained : 1) Young Gwang sand dune is taking to pieces by human impact, and dose not move ahead the process of sand dune. 2) there was a turbulence of sand sediments outcrops saying to the cryoturbation that represents cold climatic environments, 3) Constituents of sand dune are mainly fine and very fine sand(2.5~4.5Φ) consisted by quartz and feldspar. Young Gwang sand grians have some analogy with different sites in west coast 4) In surface texture, roundness is thought to have been formed sub-angular, and some V cracks represented mechanical weathering environments. Especially, the dune environment has significant cultural and archaeological values arising from the occupation of human in the past. Those areas where occupation is known provide a valuable source of past records relating to human settlement.