• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.293-300
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• 2019

As a common side effect of fixed orthodontic treatment, demineralization of the enamel adjacent to the bracket and band occurs in patients with poor oral hygiene. The purpose of this study was to investigate what is the most effective method to prevent demineralization around the fixed orthodontic appliance among various methods using fluoride. 80 extracted bovine incisors with a healthy surface were classified into four groups as experimental materials: (Group I) Control group, (Group II) V $varnish^{TM}$, (Group III) Tooth Mousse $Plus^{(R)}$, (Group IV) $Vanish^{TM}$ XT. After treatment for each group, mineral loss and Vickers surface microhardness were measured at 0, 30, 60 and 90 days after demineralization in artificial carious solution. Mineral loss was the lowest in group IV, followed by group II and group III, which showed a significant difference. The surface microhardness was the lowest in group IV, followed by group II and group III, which showed a significant difference. Through this study, group IV showed the best effect to prevent enamel demineralization around the bracket. Group III showed significant prevention of enamel demineralization compared with the control group, but the effect was less than that of the other groups.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.213-221
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• 2017

This study empirically investigates the relation between information quality measured by accruals quality and the KOSPI200 index rebalancing. The accruals quality is used for the proxy of information quality and is estimated by employing the Francis et al. (2005) model. The result shows that there is a statistically significant difference between additions group and deletions group. The average information quality of deletions group is substantially lower than that of additions group. In addition, the regression analysis shows that the relationship between accruals quality and a dummy variable for changes in the KOSPI200 index composition is negative and statistically significant. This result implies that additions to the KOSPI200 stock index improves information quality and relieves the information risk of firm which results in the amelioration of information asymmetry. On the other hand, deletions from the KOSPI200 index result in the deterioration of information quality. These results are consistent with Merton (1987).

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.595-607
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• 1999

The purpose of this in vitro study was to evaluate the efficacy of self-etching primer which was developed to simplify the bonding procedures by measuring the shear bond strength and observing the interfacial morphology. 90 flat dentinal surfaces were prepared by grinding the buccal and lingual areas of caries-free human deciduous molars. After bonding of composite resin to sample surfaces according to the manufacturer's direction and thermocycling, shear bond strengths were measured using Universal testing machine(Instron). Another groups of specimens were treated by hydrochloric acid to secure the resin only and those tags were evaluated under SEM for their length and forms and the morphology of the bonding sites were also observed. The result as follows. 1. Group III showed higher shear bond strength than group I and II but no statistically significant difference was founded between group I and II(p>.05). 2. Adhesive failure was predominant in group II whereas dentin detachment was the main failure pattern in group I and III. 3. Relating long resin tags of $100-200{\mu}m$ were observed in samples of all groups under SEM. In group I, homogeneously long resin tags were arranged rather tight whereas rather loosely arranged resin tags of various length were found in group II. Lateral branching of resin tags was the characteristic finding observed in group III.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.17 no.1
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• pp.3-9
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• 2006

Objectives: Obesity is one of risk factors for psychological and social adjustment problems (depression, low self esteem, low school function etc). Quality of life(QOL) is comprehensive and multidimensional construct including physical, emotional, social and school functioning. Some authors reported that child and adolescent obesity is associated with impaired QOL. This study was to examine the association between QOL and body mass index (BMI) in middle school students. Methods : Cross sectional analysis of 471 adolescents between the ages of 13 and 14 years ($mean{\pm}SD,\;13.4{\pm}0.6$), who attended one of middle schools in Seoul, Korea. Participants' QOL were scored by using Korean version of pediatric QOL inventory generic score scale ($PedsQL^{TM}$ 4.0). Participants had a $mean{\pm}SD\;BMI\;of\;21.3{\pm}4.0$. Self reports and parent proxy reports using $PedsQL^{TM}$ 4.0 were administered to measure participant's QOL. Participants were divided into four groups by BMI (Male: obesity group >26.5, at risk group 23.2-26.5, normal weight group 15.8-23.1, underweight group <15.8, Female : obesity group >25.2, at risk group 22.9-25.2, normal weight group 16.0-22.8, underweight group <16.0). Results : Compared with other groups, obese adolescents reported significantly(p<0.01) love. QOL in all domains. Obese adolescents were more likely to have impaired QOL than normal weight adolescents (Odds Ratio, 8.3, 95% confidence interval, 4.0-16.7). Conclusion : Obese adolescents have lower QOL than normal weight adolescents. Psychiatrist, parents, and teachers need to be informed of the risk fur impaired QOL in obese adolescents to target interventions that could enhance health outcomes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.524-537
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• 2017

This study examined the relationship between the sociodemographic characteristics, health related factors, physical functions (ADL, IADL), mental functions (CES-D, MMSE-K), oral health impact profile (OHIP-14), and the quality of life (WHOQOL-BREF) for the elderly in long-term care facilities. The research was conducted in 602 facility allowance beneficiaries authorized to be eligible for long-term care in long-term care facilities through personal interviews using a structured questionnaire from May 1 to June 30, 2016. As a result, the quality of life was lower among females than males in the group receiving government subsidies than the group whose livelihood was maintained by themselves or their children, in the group with a longer period of care, in the drinking group than the non-drinking group, in the group with irregular exercise than the regular exercise, in the group with irregular meals than regular meals, in the group with poor subjective health conditions than good subjective health condition, in the group with a smaller number of daily toothbrushing, in the group with xerostomia than no xerostomia, in the group with a lower OHIP-14, in the group with a lower ADL and IADL, and in the group with a lower CES-D and MMSE-K. In particular, the quality of life was affected more by health-related factors and CES-D and MMSE-K than by other factors. Therefore, it is necessary to make efforts to prevent depression and cognitive impairment, including health-related behavior, with the objective of improving the quality of life for the elderly in long-term care facilities.

• Restorative Dentistry and Endodontics
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• v.36 no.1
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• pp.50-58
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• 2011

Objectives: The purpose of this study was to compare the microshear bond strength (uSBS) of two totaletch and four self-etch adhesive systems and a flowable resin to enamel. Materials and Methods: Enamels of sixty human molars were used. They were divided into one of six equal groups (n = 10) by adhesives used; OS group (One-Step Plus), SB group (Single Bond), CE group (Clearfil SE Bond), TY group (Tyrian SPE/One-Step Plus), AP group (Adper Prompt L-Pop) and GB group (G-Bond). After enamel surfaces were treated with six adhesive systems, a flowable composite resin (Filek Z 350) was bonded to enamel surface using Tygon tubes. the bonded specimens were subjected to uSBS testing and the failure modes of each group were observed under FE-SEM. Results: 1. The uSBS of SB group was statistically higher than that of all other groups, and the uSBS of OS, SE and AP group was statistically higher than that of TY and GB group (p < 0.05). 2. The uSBS for TY group was statistically higher than that for GB group (p < 0.05). 3. Adhesive failures in TY and GB group and mixed failures in SB group and SE group were often analysed. One cohesive failure was observed in OS, SB, SE and AP group, respectively. Conclusions: Although adhesives using the same step were applied the enamel surface, the uSBS of a flowable resin to enamel was different.

• Restorative Dentistry and Endodontics
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• v.33 no.2
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• pp.90-97
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• 2008

The purpose of this study was to evaluate the effect of passive or active application of primer and coat times of bond on the shear bond strength when a self-etching primer adhesive (Clearfil SE Bond) was applied to enamel surface. Crowns of sixteen human molars were selected. Buccal and lingual enamels of crowns were partially exposed and slabs of 1.2 mm thick were made. They were divided into one of four equal groups (n = 8). Group 1: passive application of Primer and 1 coat of Bond, Group 2: active application of Primer and 1 coat of Bond, Group 3: passive application of Primer and 2 coats of Bond, Group 4: active application of Primer and 2 coats of Bond. Clearfil AP-X was bonded to enamel suface of each group using Tygon tubes. The bonded specimens were subjected to microshear bond strength (uSBS) testing with a crosshead speed of 1 mm/min. The results of this study were as follows; 1. The uSBS of Group 1 was the lowest among groups and the uSBS of Group 4 was the highest. 2. There was not statistically significant interaction between enamel uSBS by application method of Primer and coat time of Bond (p > 0.05). 3. There was not statistically significant difference between enamel uSBS by passive and active application of Primer (p > 0.05). 4. There was statistically significant difference between enamel uSBS by one- and two-coat of Bond (p < 0.05).

• Korean Journal of Social Welfare Studies
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• v.42 no.3
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• pp.355-379
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• 2011

The purpose of this study is to reveal the similarity and difference by comparing the quality of life between senior citizen group and disabled people group. For this purpose, I surveyed the questionnaire composed of sociological variable of population, social support, society activity participation, activity of daily living, self-efficacy, and quality of life to 113 senior citizens and 107 disabled people and analyzed the actual proof relationship of cause and effect in between variables. I executed the analysis of structural equation model by using SPSS 14.0 and AMOS 7.0 for the analysis of data. As the result of the study, firstly, the variables highly co-related with the quality of life to both senior citizen group and disabled people group were self-efficacy and society activity participation, and the variables highly co-related with self-efficacy were the quality of life and society activity participation. Secondly, the variables which show the meaningful difference between senior citizen group and disabled people group were society activity participation and activity of daily living. Thirdly, in the senior citizen group, social support, society activity participation, and activity of daily living have meaningful effect on self-efficacy, and all variables have meaningful effect on the quality of life. However, in the disabled people group, social support did not have meaningful effect on self-efficacy, and the social support and self-efficacy did not have meaningful effect on the quality of life. Based upon these study results I discussed the meaning and implications of the study, and suggested the successive study tasks.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.545-553
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• 2003

To achieve good dentin bonding, we must obtain proper wet dentin surface. The purpose of this study was to compare dentin surface according to different wetness degree by AFM image as studying how to obtaining proper wet dentin surface. Intact recently extracted primary teeth were used in the study. The extracted teeth were stored in distilled water at $4^{\circ}C$ until prepared. The teeth were used to prepare 1mm thick dentin disks with exposed surfaces parallel to the occlusal surfaces. The surface of the dentin were polished with polishing disk. The sample were ultrasonically cleaned with distilled water. The sample of each group were treated by different ways. We compared dentin surface of each group by AFM image. From the experiment, the following results were obtained. 1. Acid etching in the dentin surface of primary teeth, resulted in the removal of the smear layer, which opened dentinal tubules, caused the demineralization of peritubular and intertubular dentin, and exposed a collagen-rich transition zone. 2. If the etched dentin was so dehydrated, the intertubular dentin surfaces deceased in height and the diameters of the dentinal tubules decreased slightly. 3. In the group dried with compressed air for 20 seconds at 2 cm, the dentin surfaces were too excessive dried and dehydrated. 4. In the group dried with compressed air for 3 seconds at 2 cm, dry cotton, wet cotton, microbrush and absorbent tissue paper, the dentin surfaces were properly wet.

• The KIPS Transactions:PartD
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• v.13D no.4 s.107
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• pp.501-512
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• 2006

XML is the most popular platform-independent data expression which is used to communicate between loosely coupled heterogeneous systems such as B2B Applications or Workflow systems. The powerful query language XQuery has been developed to support diverse needs for querying XML documents. XQuery is designed to configure results from diverse data sources into a uniquely structured query result. Therefore, it became the standard for the XML query language. Although the latest XQuery supports heavy search functions including iterations, the grouping mechanism for data is too primitive and makes the query expression difficult and complex. Therefore, this work is focused on supporting the groupby clause in the query expression to process XQuery grouping. We suggest it to be a more efficient way to process grouping for restructuring and aggregation functions on XML data. We propose an XQuery EBNF that includes the groupby clause and implemented an XQuery processing system with grouping functions based on the eXist Native XML Database.