• The korean journal of orthodontics
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• v.41 no.5
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• pp.354-360
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• 2011

Objective: To investigate the effects of different pilot-drilling methods on the biomechanical stability of self-tapping mini-implant systems at the time of placement in and removal from artificial bone blocks. Methods: Two types of artificial bone blocks (2-mm and 4-mm, 102-pounds per cubic foot [102-PCF] polyurethane foam layered over 100-mm, 40-PCF polyurethane foam) were custom-fabricated. Eight mini-implants were placed using the conventional motor-driven pilot-drilling method and another 8 mini-implants were placed using a novel manual pilot-drilling method (using a manual drill) within each of the 2-mm and 4-mm layered blocks. The maximum torque values at insertion and removal of the mini-implants were measured, and the total energy was calculated. The data were statistically analyzed using linear regression analysis. Results: The maximum insertion torque was similar regardless of block thickness or pilot-drilling method. Regardless of the pilot-drilling method, the maximum removal torque for the 4-mm block was statistically higher than that for the 2-mm block. For a given block, the total energy at both insertion and removal of the mini-implant for the manual pilot-drilling method were statistically higher than those for the motor-driven pilot-drilling method. Further, the total energies at removal for the 2-mm block was higher than that for the 4-mm block, but the energies at insertion were not influenced by the type of bone blocks. Conclusions: During the insertion and removal of mini-implants in artificial bone blocks, the effect of the manual pilot-drilling method on energy usage was similar to that of the conventional, motor-driven pilot-drilling method.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.7
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• pp.1075-1081
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• 2013

Twitter, Facebook, and KakaoStory are the major SNS in Korea. Social knowledge production is being produced by those services from numerous collaboration and co-participation in those SNS. Wikipedia or Naver JishikIN service was regarded as the representative product of collective knowledge production during the wired internet era. However now at the wireless internet era centered with smart phones, various forms of collective knowledge production would be achieved by connecting to SNS in real-time. In this thesis, the survey data of collective knowledge production for users of three SNS have been compared and analyzed. The difference of the collective knowledge production mechanism among Twitter, Facebook and KakaoStory has been studied and compared through three variables: the motivation of collective knowledge production, the preference of collective knowledge production model, and collective knowledge production cultural perception. As a result of the analysis of the discriminant factors for three SNS user groups, it turns out that the diversity-toward usage motivation, personal contribution motivation, and collective knowledge production tendency perception are the most influential variables. This thesis is of significance in that it unites the value of social science such as social capital and collective knowledge production from the viewpoint of computer science and opens the new chapter of collective knowledge production with the real-time SNS of wireless internet from the wired internet.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.72-83
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• 2017

This study was conducted to investigate nursing students' safety-climate: perception and performance of standard precautions for healthcare-associated infection control. We also identified actors influencing performance of standard precautions. Data were collected from 246 junior and senior nursing students at nine colleges in D city from July to September, 2016. The mean score of performance was significantly lower than that of perception in all areas of standard precautions. The biggest difference between perception and performance was in the usage of personal protective equipment and safe injection practices. We also detected significant positive correlations among safety-climate, perception, and performance of standard precautions. In the regression analysis, performance of standard precautions was influenced by safety-climate and grade accounting for 10.7% of variance. To improve healthcare-associated infection control among nursing students, safer and more supportive practical environments need to be provided, and new training strategies such as simulation education need to be expanded.

• Korean Journal of Remote Sensing
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• v.21 no.4
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• pp.287-302
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• 2005

Digital Elevation Models (DEMs) were generated by ERS-l/2 and JERS-1 SAR interferometry in Daejon area, Korea. The quality of the DEM's was evaluated by the Ground Control Points (GCPs) in city area where GCPs were determined by GPS surveys, while in the mountain area with no GCPs, a 1:25,000 digital map was used. In order to minimize errors due to the inaccurate satellite orbit information and the phase unwrapping procedure, a Differential InSAR (DInSAR) was implemented in addition to the traditional InSAR analysis for DEM generation. In addition, DEMs from GTOPO30, SRTM-3, and 1:25,000 digital map were used for assessment the resolution of the DEM generated from DInSAR. 5-6 meters of elevation errors were found in the flat area regardless of the usage and the resolution of DEM, as a result of InSAR analyzing with a pair of ERS tandem and 6 pairs of JERS-1 interferograms. In the mountain area, however, DInSAR with DEMs from SRTM-3 and the digital map was found to be very effective to reduce errors due to phase unwrapping procedure. Also errors due to low signal-to-noise ratio of radar images and atmospheric effect were attenuated in the DEMs generated from the stacking of 6 pairs of JERS-1. SAR interferometry with multiple pairs of SAR interferogram with low resolution DEM can be effectively used to enhance the resolution of DEM in terms of data processing time and cost.

• Korean Journal of Social Welfare Studies
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• v.49 no.2
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• pp.257-295
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• 2018

This study delineates how recipients access, understand, and make use of social welfare information in their life-worlds. Through this vivid illustration about recipients' information behaviors, this research aims to suggest that government-centred welfare informatization policy should be readjusted. South Korean government has made enormous efforts to deliver and share social welfare information and knowledge with recipients, by organizing IT eduction programmes, offering free computers, and opening welfare portals. However, despite of such endeavors, not a few recipients find difficulty in gaining, grasping, and using welfare information. In fact, welfare informatization programmes have so far been initiated by the governmental bureaucratic system, and the voice of recipients have hardly been reflected on the informatization policy. Starting from this problem, this study examines how low-income recipients perceive and accept social welfare information in their daily lives and reflects on social welfare information at their point. For this purpose, this research conducted in-depth interviews with 14 recipients and analyzed the data using a framework analysis method. Based on the results, it raises the need for the remodelling of current welfare informatization measures from the perspective of recipients rather than following the custom of the bureaucratic system.

• Journal of Advanced Technology Convergence
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• v.1 no.1
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• pp.15-24
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• 2022

This paper tried to investigate the moderating effect of chemyon sensitivity and usage situation in the relationship between self-presentation and brand preference. Data were collected from students of universities located in Chungnam. The analysis results can be summarized as follows. First of all, the effect of self-presentation on symbolic brand preference was not significant in both public and private use situations. On the other hand, the effect of self-presentation on functional brand preference was found to be significant in both situations. Second, the main effect of chemyon sensitivity was significant only when it had a negative effect on functional brand preference in public situations, but was not significant in other cases. Third, looking at the interaction effect of self-presentation and chemyon sensitivity, the brand preference did not show significant changes in those with relatively low chemyon sensitivity, regardless of the level of self-presentation, whether in public or private situations. This study is meaningful in that it reveals that chemyon sensitivity affects brand preference through interaction with self-presentation, whether the consumption situation is public or private.

• Journal of Korean Home Economics Education Association
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• v.35 no.4
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• pp.33-45
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• 2023

The purpose of this study is to investigate the association between dietary behavior and related factors according to the generalized anxiety disorder (GAD) in adolescents. The results of analyzing demographic characteristics according to the GAD showed that gender, age, BMI, type of school, residence type, father's nationality, smoking and drinking experience, perceived health status, perception of body shape, economic status, academic achievement, physical activity, sedentary time and smartphone usage time were related to the GAD (p<0.01). The results of analyzing dietary behavior according to the GAD showed that the frequency of water intake, sweetened beverage intake, fast food intake, fruit intake and breakfast intake were related to the GAD (p<0.001). The results of analyzing depression and suicidality according to the GAD showed that depression, suicidal ideation, planning, and attempts were all related to the GAD (p<0.001). Even after adjusting for factors corresponding to demographic characteristics, it was confirmed that the level of GAD had a significant effect on depression and suicidality. This study is significant in that it provided basic data on adolescent mental health problems by analyzing dietary behavior and related factors according to the level of GAD.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.161-166
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• 2016

By studying the status of oral health provided by caregivers working in care facilities in accordance with their oral health awareness and knowledge, this thesis sought to find a plan of development to enhance the oral health for the elderly in care facilities. A survey was carried out from the 16th of August to the 2nd of September 2016, with 200 care givers as the subjects, working in 14 long-term care facilities for elderly, located in the city of D. Frequency analysis and independent sample t-test were conducted of the collected data, using SPSS 18.0. The results of the study were as follows; for gender, female was 91.5% which was higher than that of male, and married for marital status, 50 for age, highschool for education, christian for religion were shown to be the highest. The highest number of people for daily care was 6~7. In terms of status for providing oral health and oral health awareness of caregivers, the existence of oral hygiene guideline was statistically meaningful, and in terms of the status of oral health provided and oral health knowledge, there were notable differences in storage of dentures, and usage of mouthwash(p<.05).

• Korean Journal of Remote Sensing
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• v.33 no.2
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• pp.231-242
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• 2017

Monitoring of facilities such as roads, dams and bridges is important for their long-term sustainable usage. It has usually suffered with safety and cost problems, which makes more frequent monitoring difficult. As an efficient and economicalsolution to these problems, one may consider the use of smartphone to capture the status of the facilities. To derive quantitative analysis results with the smartphone images for facility monitoring, one should first rectify the images in a way as automatic and economical as possible. In thisstudy, we propose such a rectification method, which rectifiessmartphone images acquired from arbitrary locations based on reference images.In the proposed method, we determine the camera extrinsic parameters of each smartphone images using the reference imagesrather than ground control points, and project the image to the target surface of the facility based on the determined camera parameters. The method were applied to test data acquired from a small dam toward water-area facility monitoring. The experimental results showed that the camera extrinsic parameters were determined with the accuracy of 5 cm and $0.28^{\circ}$ in the position and attitude. The accuracy of the distance measured from the rectified image was evaluated to 10 cm. With the rectified images, one can accurately determine the location and length of the target objects required for facility monitoring.

• Korean Journal of Social Welfare
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• v.69 no.1
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• pp.175-197
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• 2017

This study aims to analyze the formation of Korean social welfare delivery system and its pathway, from which the pending issues are to be discussed on the organizations and personnel of the delivery system using the word 'social welfare' with its related discourse. Historical institutionalism is chosen as the perspective to explain path-dependent change and critical juncture, and various legislative data are used as the indicative signals for the discourse of 'social welfare'. The results of the study are as follows. First, the term 'social welfare' began to be institutionalized in Korea by the enactment of Livehood Protection Law(1961). Second, the policies by the year 1987 of expanding social welfare center and introducing social welfare professionals as civil servants form a critical juncture which makes the social welfare discourse realized as the institutional realities. Third, until the year around 2014, the system has not changed in the perspective of macro framework. Fourth, currently the system shows several signs of severe turmoil, which might lead to dismantle the system of 'social welfare' discourse. To conclude, this study shows the possibility of explaining organizations and personnel composing the social welfare delivery system by the usage of discourse analysis, treating it as an analytical entity.