• Restorative Dentistry and Endodontics
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• v.11 no.1
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• pp.77-88
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• 1985

The purpose of this study was to examine the thermal diffusion through bases and restorations. The three principle types of base and two restorative materials were included in this study. They were representive brands of a zinc phosphate cement, a zinc oxide-eugenol cement, a calcium hydroxide paste, an amalgam and a composite resin (table 1). The specimens were prepared by placing the bases or restorative materials in laminated plastic molds. 5-mm diameter holes were prepared in the center of square of plastics which were 0.5, 1.0, 2.0, and 3.0mm thick respectively (fig. 1). All materials were manipulated in accordance with manufacturer's recommended proportions. All experimental procedures were carried out dividing them into eight different groups (table 2). Thermal diffusion was measured by means of digital thermometer (DP-100, RKC. instrument Inc. JAPAN) with the surface thermocouple placed on bottom surface of the specimen applying a constant source of heat and cold to the top surface of the each specimen. The thermal stimulus temperature applied on the each specimen surface was in the range of $60^{\circ}C$, $0^{\circ}C$ and $-50^{\circ}C$ respectively. The thermal change were recorded automatically on the multi-Pen recorder (R-16, Rikadenki, Co. JAPAN) connected with thermocouple tips which were centered on the bottom of the specimen. The following results were as follows, 1. Temperature diffusion was highest through amalgam and slowest through the composite resin. 2. As the thickness of restorations increased, the temperature change was decreased. 3. Thermal diffusion was slowest in the presence of zinc oxide-eugenol bases, followed by calcium hydroxide and zinc phosphate cement. 4. The efficiency of the cement bases in providing thermal insulation was dependent on their thickness beneath the restorations. 5. Thermal change was great in the range of $60^{\circ}C$ and $-50^{\circ}C$, but little in the range of $0^{\circ}C$.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.129-136
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• 2021

This study aims to verify the influence of married men in their 30s and 40s on smartphone addiction, the mediating effect of depression, and the moderating effect according to age. To this end, samples were set up as a convenient sampling for married men in their 30s and 40s living in the Seoul, Gyeonggi, Incheon metropolitan. To verify the influence relationship, mediating effect, and moderation effect of the main variables, we compare the differences in influence by dividing age groups through spss win 25 program Baron & Kenny's analysis, Sobel test, and multi-regression analysis. The analysis results are as follows. First, stress has a positive effect on depression and smartphone addiction, and depression has a positive effect on smartphone addiction. Second, depression has been shown to have a partial mediating effect in the relationship between stress and smartphone addiction. Third, there was a difference in influence between stress and smartphone addiction depending on age groups. Based on the above results, we present policy implications and follow-up research suggestions.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.113-127
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• 2021

Although planning techniques linking parks, green areas, and waterways have become common, there are frequent disruptions in the operation and management of landscape-use artificial channels (LuAC). Therefore, this study examined a design to promote the sustainable management and operation of a LuAC using rainwater for the streamlets of the Jeonju-Wanju Innovative City. In order to accomplish the purpose of this study, scenarios were set up by dividing the design into waterhead and waterway portions. First, the scenario regarding the waterhead was analyzed to calculate the water supply and storage required for the waterway and waterhead. The analysis showed that the waterway requires a water supply of 676.8 tons/months, 3,018 tons to 5,512 tons of storage space, and a water depth of 0.75 m to 1.37 m considering the ecological and landscape aspects. The second scenario is to select an effective system of facilities for the operation and management of the LuAC. To accomplish this, a single-circulation system (SCS), which transports water to a highland location was compared to a multi-circulation system (MCS), which supplied water separately to each water space and operated independently. The results showed that the MCS, which was operated independently by small power units, was more effective owing to the vast difference in water supply operation times.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.701-710
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• 2018

This study aims to verify the mediating effect of perceived risk of internet shopping mall users' innovativeness on product purchase intention. Research subjects included consumers with prior experience of using internet shopping malls, and 405 respondents were used for final analysis. The major findings of the study are as follows: First, as a result of the investigation on the relationships among users' innovativeness, perceived risk, and product purchase intention, all correlation coefficients were positive. Second, consumer innovativeness was found to significantly influence perceived risk and purchase intention, and perceived risk mediated the relationship between consumer innovativeness and purchase intention. Third, when we performed sub-group analysis on the research model by dividing products into hedonic and utilitarian products, it was found that hedonic products revealed path coefficients which are statistically more significant compared with those for utilitarian products. We can draw the conclusion that in terms of internet shopping mall purchases, hedonic products exert a greater influence on the effect of consumer innovativeness on purchase intention compared to utilitarian products.

• Korean Journal of Family Social Work
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• no.55
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• pp.91-128
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• 2017

The purpose of this study is to develop an effective intervention strategy for marriage migrant woman in family therapy. For this purpose, we collected counseling cases of professional counselors who successfully completed counseling and attempted the qualitative analysis of treatment intervention strategies and effects. The results of the study were obtained by dividing the meaning units in the immigrant woman's statements made during the counseling process composed of a total of 6 sessions. The counselors were analyzed to have tried the following intervention strategies. They attempted the following six strategies: Helping emotional differentiation by searching for unresolved emotional problems, dealing with undifferentiation due to family projection process and love triangle, dealing with multi-generational transfer process of the original family relationship patterns and coping mechanism, shedding lihgt on ineffectiveness of inconsistent communication due to emotional oppression applying a communication model of MRI, switching client's awareness through reorganization, suggesting a way of communication that leads to real self. Such counselors' attempts resulted in positive changes and treatment effects were found to include first, cognitive insights and motivation for change, second, improved communication skills and third, anxiety reduction and self-differentiation. Due to their husbands' refusal to participate in counseling, marriage migrant women often get involved in counseling alone, so they tend to worry that the effectiveness of family therapy may be low but it was found that the proper intervention of the counselor could improve the ability of the wife to resolve conflicts, which would be a great help in solving problems such as family violence and this study is meaningful in that it provided the appropriate therapeutic intervention strategies needed.

• The korean journal of orthodontics
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• v.52 no.1
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• pp.66-74
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• 2022

Objective: To investigate demographic and skeletodental characteristics of one-jaw (1J-OGS) and two-jaw orthognathic surgery (2J-OGS) in patients with skeletal Class III malocclusion. Methods: 750 skeletal Class III patients who underwent OGS at 10 university hospitals in Korea between 2015 and 2019 were investigated; after dividing them into the 1J-OGS (n = 186) and 2J-OGS groups (n = 564), demographic and skeletodental characteristics were statistically analyzed. Results: 2J-OGS was more frequently performed than 1J-OGS (75.2 vs. 24.8%), despite regional differences (capital area vs. provinces, 86.6 vs. 30.7%, p < 0.001). Males outnumbered females, and their mean operation age was older in both groups. Regarding dental patterns, the most frequent maxillary arch length discrepancy (ALD) was crowding in the 1J-OGS group (52.7%, p < 0.001) and spacing in the 2J-OGS group (40.4%, p < 0.001). However, the distribution of skeletal pattern was not significantly different between the two groups (all p > 0.05). The most prevalent skeletal patterns in both groups were hyper-divergent pattern (50.0 and 54.4%, respectively) and left-side chin point deviation (both 49.5%). Maxillary spacing (odds ratio [OR], 3.645; p < 0.001) increased the probability of 2J-OGS, while maxillary crowding (OR, 0.672; p < 0.05) and normo-divergent pattern (OR, 0.615; p < 0.05) decreased the probability of 2J-OGS. Conclusions: In both groups, males outnumbered females, and their mean operation age was older. The most frequent ALD was crowding in the 1J-OGS group, and spacing in the 2J-OGS group, while skeletal characteristics were not significantly different between the two groups.

• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.231-245
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• 2022

Most humans live at work and continue their lives through work. This study aims to understand the influence of job crafting on job satisfaction and knowledge sharing behavior, innovation behavior, and smart work environment variables in the rapidly changing labor market. In addition, a study was conducted on the effect of job crafting on job satisfaction by dividing it into male and female groups. The study was conducted on 453 office workers who responded to the survey, and SPSS 26.0 and Amos 26.0 were used. Frequency analysis, exploratory factor analysis, confirmatory factor analysis, reliability analysis, descriptive statistics, correlation, structural model analysis and Multi-group analysis were performed. Multiple mediating effects were analyzed and Process macro model 7 was used as the smart work environment effect. As a result of the analysis, first, job crafting had a significant effect on job satisfaction, and second, job crafting had a significant effect on knowledge sharing behavior and innovation behavior. Third, knowledge sharing behavior had a significant effect on job satisfaction, but innovation behavior did not affect job satisfaction. Fourth, for the parameters of knowledge sharing behavior and innovation behavior, knowledge sharing behavior had a partial mediating effect, but innovation behavior did not affect it. Fifth, it was found that the moderating effect of the smart work environment had no effect, and sixth, the results of a study on the effect of job crafting on job satisfaction divided into men and women had a greater effect than men.

• Smart Media Journal
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• v.11 no.5
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• pp.75-81
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• 2022

In order to respond to carbon neutrality and climate change in agriculture, agricultural machinery, which has been developed centered on internal combustion engines, needs to be converted to an electric-based technology that does not emit greenhouse gases. In this study, simulations for electric UTV suspension design were performed to reduce vibration and shock of electric UTV for agricultural use and to improve driving stability and control performance of the vehicle. The simulation was performed by dividing the tolerance load of the vehicle body and the loaded load state. The range of motion of the suspension spring of UTV is within 30% of the range of motion under condition B under tolerance, the displacement of the UTV suspension with full load is reduced from 264mm to 121mm, and the damping speed is 260mm/s to 300mm/s that it can be seen that the range of motion is within 60%. Suspension design of electric UTV for multi-purpose agricultural work is a very important factor for maintaining agricultural work ability in towing work such as tillage as well as driving and terrain adaptation. The results of this study can be usefully used to determine the spring parameters with the appropriate damping range so that the electric UTV can be used for various agricultural tasks.

• Journal of the Korean Society for Library and Information Science
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• v.58 no.2
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• pp.57-80
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• 2024

Eisner emphasized the importance of problem-solving objectives and expressive objectives in addition to behavioral objectives, and communication through multiple modalities including linguistic, visual, aural, spatial, gestural modes. This study analyzes 'Libraries and Information Life,' a textbook developed for information literacy instruction, by dividing it into educational objectives types(behavioral, problem-solving, expressive) and multimodal modes(linguistic, visual, auditory, spatial, and gestural), and seeks to derive implications for setting educational objectives for information literacy instruction and developing textbooks. The textbook has four volumes for elementary low-grade, elementary high-grade, middle school, and high school levels. Educational objectives were extracted from the textbooks, and 3 librarian-teachers were engaged in the analysis of these objectives. The main findings and implications of this study are as follows. First, when looking at the types of educational objectives, the proportion of behavioral objectives was found to be excessively high, and there is a need to strengthen the proportion of problem-solving objectives and expressive objectives. Second, problem-solving objectives tend to overlap with behavioral objectives, indicating a need to develop problem-solving objectives with defined conditions and solution requirements. Third, expressive objectives concentrated in specific units need to be placed evenly in other units. Fourth, in the case of multi-modality mode, the proportion of the linguistic mode must be reduced, the proportion of the visual, auditory, spatial, and gestural modes must be increased, and it is necessary to set educational objectives with clear characteristics of each mode.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.284-295
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• 1999

The purpose of this study was to measure and analyze the bond strength of bonded amalgam using dental adhesives and to compare this with light-curing composite resin. Sections 8mm in diameter were punched out from the labial surface of bovine anterior teeth. These were embedded in clear acrylic resin blocks with labial surface facing out. 55 specimens were made for enamel and dentin each. After dividing these into 5 groups, group 1: Superbond C&B, group 2: Panavia 21, group 3: All-Bond 2, group 4: Fuji I Glass Ionomer Luting Cement, group 5: Scotchbond Multi-Purpose(Restorative Z-100), molds with holes of 6.3mm in diameter and 1.5mm in depth were placed over the specimens. The exposed tooth surfaces were treated with adhesives and the molds were filled with amalgam. In group 5, the mold was filled with composite resin and light-cured for 40 seconds. The author measured all specimens for bond strength 24 hours after amalgam filing and analyzed fracture surfaces. The following results were obtained: 1. Among the dentin groups, groups 1, 2 and 4 showed significantly lower bond strength compared with group 5(P<0.05). 2. Among the enamel groups, group 4 showed significantly lower bond strength compared with group 5(P<0.05). 3. In group 2, 2D showed significantly lower bond strength compared with group 2E(P<0.05). Other adhesives showed no such differences in bond strength between dentin and enamel(P>0.05). 4. Cohesive failure was observed in groups 1E and 5D, while mixed failure was seen in groups 1 and 5. Only adhesive failures were noted in groups 2, 3, 4.