• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.136-147
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• 2009

Statement of problem: Since the introduction of the concept of osseointegration in dental implants, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. Purpose: The aim of this retrospective study was to provide long-term data on the $Implantium^{(R)}$ implant, which features a sandblasted and acid-etched surface and internal connection with microthreads. Material and methods: 106 $Implantium^{(R)}$ implants placed in 38 patients at Yonsei University Hospital were examined to determine the effect of various factors on implant success and marginal bone loss, through clinical and radiographic results during a 6 to 30 month period. Results: 1. Out of a total of 106 implants placed in 38 patients, one fixture was lost, resulting in a 99.1% cumulative survival rate. 2. Among the 96 implants which were observed throughout the study period, the survival rates were 97.0% in the maxilla and 100% in the mandible. The survival rate in the posterior regions was 98.9% and 100% in the anterior regions. 3. The mean bone loss during the first year after prosthesis placement was 0.17 mm, while the mean annual bone loss after the first year was 0.04 mm, which was statistically less than during the first year(P<.05). 4. There was no significant difference in marginal bone loss according to age during the first year(P>.05), but after the first year, the mean annual bone loss in patients above 50 years was significantly greater(P<.05) compared with patients under 50 years. 5. No significant difference in marginal bone loss was found according to the following factors: gender, jaw, location in the arch, type of implant(submerged or non-submerged), presence of bone grafts, type of prostheses, and type of opposing dentition(P<.05). Conclusion: Based on these results, the sole factor influencing marginal bone loss was age, while factors such as gender, jaw, location in the arch, type of implant, presence of bone grafts, type of prostheses and type of opposing dentition had no significant effect on bone loss. In the present study, the success rate of the $Implantium^{(R)}$ implant with a SLA surface and internal connection with microthreads was satisfactory up to a maximum 30 month period, and the marginal bone loss was in accord with the success criteria of dental implants.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.275-289
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• 2011

We investigated the hydrological and geomorphological characteristics of small irrigation ponds in civilian control zone of Paju city in Korea. Among 85 small irrigation ponds, water level of 52 ponds changed seasonally and that of 33 was constant. Water sources of 12 ponds were surface water, 29 surface water and ground water, and 44 ground water. 4 ponds locate in the edges of forests, 33 in flat-lands, and 48 in valleys. Water in 45 ponds was exchanged with paddy fields and 40 ponds were isolated from paddy fields. Endangered or endemic species were inhabited in 26 ponds, which have ground water as water source and constant water level. Based on these characteristics, we suggested 4 types of small irrigation ponds: spring, water exchanging, stagnant/spring, stagnant water. This classification system will help ecosystem managers to investigate ponds systematically and manage them based on pond type.

• Journal of Internet Computing and Services
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• v.15 no.2
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• pp.73-85
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• 2014

This study analyzed the profile of a Facebook account to examine how personal information is revealed and what kinds of factors influence personal information revelation. Categories of user's profile on Facebook were analyzed and two dimensions were developed; the degree that how much personal information is revealed and the network limits that personal information is accessed. Main variables to determine personal information revelation are Facebook privacy concern and uses for social relationships along with gender, the duration of Facebook use, and average time of use. Data were collected from college students. Factor analysis produced two factors of Facebook privacy concern, Facebook privacy concern with users and Facebook privacy concern with the Facebook system. Regression analyses were performed to identify significant determinants of the degree of information revelation and the network limits of personal information. The results found out that the degree of personal information revelation is explained by gender, the duration of use, and use for social relationships while the network limit is explained by the duration of use and Facebook privacy concern with users. Worthy of notice is that use for social relationships and Facebook privacy concern with the Facebook system offset each other. The implications of the results are discussed. Additionally and finally the categories of profiles are graphically re-grouped to show how personal information revelation is associated with social relationship generation and maintenance.

• The Korean Journal of Woman Psychology
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• v.13 no.3
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• pp.263-282
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• 2008

This study examined the mediating role of collective self-esteem in the relationship between personal self-esteem and career aspiration, and the mediating effects of personal self-esteem and collective self-esteem on the link between social support and career aspiration. Also, This study explored whether the development of career aspiration differs by gender. A total of 316 undergraduate students(155 male and 161 female) completed measures of social support, personal self-esteem, collective self-esteem and career aspiration. Structural equation modeling results provided support for the mediating effects of personal self-esteem and collective self-esteem, In addition, the relationship model differed by gender. The results showed that the full mediation model fit of collective self-esteem in the relationship between individual self-esteem and career aspiration was better than the partial mediation model fit. Next, in the relation of social support and career aspiration, the partial mediating effect of individual self-esteem and collective self esteem was significant. Lastly, when the model of social support, individual self-esteem, and collective self-esteem, and career aspiration was tested to examine gender differences, the relations among these variables were found to be different according to gender-difference. These results suggest that evaluations and perceptions on the individual's social group as well as the individual influedced to career aspiration, interacting with the environmental factors. Also, the gender-difference of relationship model indicates that it might be different from men and women in psychological mechanism in the career aspiration formation.

• 한국노년학
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• v.37 no.3
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• pp.637-653
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• 2017

Meta-analysis was conducted on 56 studies published in Korea until April 2017 to systematically integrate factors of ego integrity of the elderly. The variables related to ego integrity were divided into 6 groups of variable, and the effect sizes were computed for each variable of their groups. The analysis results are as follows. First, the total effect size showed the middle effect size, and the effect size according to the variable group showed the largest effect size for the positive psychological variable group, followed by the negative psychological variable, the physical variable, the familial variable, the social variable and the demographic variable. Second, the largest effect size of the sub-variables on the each individual variable group showed positive psychological variable was life quality, negative psychological variable was depression, physical variable was health behavior, familial variable was children relationship, social variable was social support and demographic variable was economic status. As described above, suggesting that these variables may have a strong influence on ego integrity among the variables related to ego integrity because the quality of life, life satisfaction and depression were shown as the largest effective variables related to ego integrity.

• Proceedings of KHEA Conference
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• 2002.10a
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• pp.127-127
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• 2002

• The Bulletin of The Korean Astronomical Society
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• v.27 no.1
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• pp.19-19
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• 2002

• Proceedings of KHEA Conference
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• 2007.06a
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• pp.88-88
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• 2007

• The monthly packaging world
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• s.340
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• pp.82-86
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• 2021

• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.321-329
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• 2006

The use of tapered structural members was first proposed by Ami rikian for the economical use of materials.Generaly, tapered members are used in single-story structures with one or more bays and in cantilevered sections of ate architectural representation. If only focused on the section performance, however, the width-to-thickness ratio or t apered ratio can exced regulations. Such a case requires a study on the behavior of tapered members. To investigate the plastic and local buckling behavior of web-tapered beams, seven steel beams were the tapered ratio and the width-to-thicknes ratio. The results of maximum strength, strength deterioration, and stiffnes deterioration were compared.