• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.25 no.2
• /
• pp.68-78
• /
• 2016

Recently, digital technology has become increasingly prevalent in the dental clinic. Using a milling machine for clinic, it is possible to produce provisional restoration inside the clinic. This can promote large clinical cases such as full mouth rehabilitation with the help of a tabletop scanner, which is capable of semi-adjustable articulator equipment, and a powerful dental CAD software with excellent user convenience. In this case report, a full-mouth rehabilitation was done with digital technology to a 55 year-old female patient, who has lost vertical dimension through the attrition, and has got inclined occlusal plane with unplanned and repeated dental reconstruction. Through the design and milling of the provisional restoration in the clinic and the duplication of these provisionals by double scanning technique, a good functional and esthetic result could be achieved.

• The Journal of Advanced Prosthodontics
• /
• v.7 no.5
• /
• pp.343-348
• /
• 2015

PURPOSE. The purpose of this study was to evaluate the bond strength of composite resin on the fracture surface of metal-ceramic depending on the repair systems and surface roughening methods. MATERIALS AND METHODS. A total of 30 disk specimens were fabricated, 15 of each were made from feldspathic porcelain and nickel-chromium base metal alloy. Each substrate was divided into three groups according to the repair method: a) application of repair system I (Intraoral Repair Kit) with diamond bur roughening (Group DP and DM), b) application of repair system I with airborne-particle abrasion (Group SP and SM), and c) application of repair system II (CoJet Intraoral Repair System, Group CP and CM). All specimens were thermocycled, and the shear bond strength was measured. The data were analyzed using the Kruskal-Wallis analysis and the Mann-Whitney test with a significance level of 0.05. RESULTS. For the porcelain specimens, group SP showed the highest shear bond strength ($25.85{\pm}3.51MPa$) and group DP and CP were not significantly different. In metal specimens, group CM showed superior values of bond strength ($13.81{\pm}3.45MPa$) compared to groups DM or SM. CONCLUSION. Airborne-particle abrasion and application of repair system I can be recommended in the case of a fracture localized to the porcelain. If the fracture extends to metal surface, the repair system II is worthy of consideration.

• The Journal of Korean Academy of Prosthodontics
• /
• v.53 no.3
• /
• pp.244-249
• /
• 2015

With the recent progress of digital technology, the computer guided surgery utilizing a guide template in the placement of implant has been actively performed, and the method employing the intraoral scanner at the implant prosthesis introduced. Fabrication method of the guide template can be largely classified into design-related rapid prototyping (RP) system and vector milling system, and each of the method has its own weakness in the clinical application despite of excellent accuracy. Thus, in this case study, a working model was fabricated by the wax RP technology using images acquired by CBCT and an intraoral scanner, and the metal bushing was picked up with orthodontic resin cast upon the wax model. Using this method, a surgical guide template was fabricated and used in surgery. From this, we could obtain a satisfactory outcome clinically in the implant placement and the fabrication of the final prostheses and thus report this case herein.

• Journal of Korean Society of Forest Science
• /
• v.99 no.1
• /
• pp.36-46
• /
• 2010

The purpose of this research was to derive political suggestion to increase the demand for forest visit by analyzing the demand of forest visitors, focusing on the residents of Seoul and capital areas. The determinants of demand, which is the number of forest visit in a year, were analyzed by independent variables; six factors from factor analysis on selective attributes, demographic characteristics, and other variables related with the general matters when visiting a forest. As a result, among the independent variables, selective attribute (tourism resource factor), gender (male), and residency (Seoul) were found out to have positive(+) effect on demand for forest visit. However, other selective attribute (external factor of forestry), occupation (white-collar employee), and level of education (over college graduate) were found out to have negative(-) effect on demand for forest visit. Based on these results, implications for the expansion of demand for forest visits were derived.

• Human Ecology Research
• /
• v.52 no.5
• /
• pp.529-539
• /
• 2014

The purpose of this study was to analyze the effects of the teacher-child relationship and child's perception of the psychological control of teachers on a child's aggression. A total of 216 4th graders from Dongjak-gu and Gwanak-gu, Seoul, participated in this study. A multiple regression analysis and Pearson's correlation analysis were performed using the SPSS ver. 18.0 program. The results were as follows: first, there was a meaningful relationship between a teacher-child relationship, the teacher's psychological control and the child's aggression. Second, closeness between the teacher and the child could reduce the child's overt and relational aggression, while conflicts between the teacher and the child could increase the child's overt, relational, and overall aggression. The teacher's blame, limit of the child's self-expression, and guilt induction could increase the child's overt aggression. Further, the teacher's withdrawal of affection, emotional disapproval, blame, and limit of self-expression could increase the child's relational aggression. In particular, the teacher's blame appeared to influence both the child's overt aggression and the child's overall aggression, and the teacher's withdrawal of affection appeared to influence the child's relational aggression. These results suggest that the relationship between a teacher and a child is a matter of mutual contribution. In other words, the better the teacher-student relationship is, the greater is the decrease in the child's aggression. This study provides the basic data for the development of an aggression prevention program for elementary school children.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.1
• /
• pp.193-201
• /
• 2015

The aims of this study were to investigate (1) the status of food materials purchased by group-buying companies and (2) the satisfaction with food materials and service quality of group-buying companies in foodservice at child-care centers. In November 2013, child-care centers which were participated in a group-buying program in Gwanak-gu, Seoul were requested to complete self-reported questionnaires. One hundred and eight respondents (76.9% of directors, 23.1% of non-directors) completed questionnaires, including purchase frequency of food materials, degree of satisfaction with 'food materials' and 'operating system and service' of group-buying companies. About 60% of child-care centers purchased food materials from major companies. Respondents' overall satisfaction with 'food materials' and 'operating system and service' were '3.55' and '3.72' out of 5 points, respectively. For overall satisfaction with food materials, there were significant differences between 'public (3.79)' and 'private, home-based (3.31)' child-care centers (p=0.023). The results of multi-regression analysis showed that quality (${\beta}$=0.271, p=0.013) and price appropriateness (${\beta}$=0.284, p=0.002) were associated with overall satisfaction with food materials purchased by group-buying companies. The factors such as delivery accuracy about items(${\beta}$=-0.201, p=0.042), hygiene of delivery process (${\beta}$=-0.207, p=0.025) and communication with companies (${\beta}$=-0.317, p=0.003) were significantly associated with overall satisfaction with operating system and service provided by group-buying companies. The results of this study could be utilized for group-buying companies and the government to develop guidelines and policies on food material buying in foodservice at child-care centers.

• Korean journal of food and cookery science
• /
• v.32 no.1
• /
• pp.84-95
• /
• 2016

This study investigated the food behavior and nutritional status of children using the Nutrition Quotient (NQ). The subjects for this study were 974 students and their parents who lived in Seocho-gu, Gwanak-gu, and Dongjak-gu, Seoul. The average NQ score of the subjects was 68.3, which was a medium grade. The mean scores for balance and moderation were above the thresholds, whereas the mean scores for diversity, regularity, and practice did not reach the thresholds. According to the results of evaluation by NQ, the subjects may have insufficient intake of calcium, iron, potassium, zinc, vitamin A, and vitamin C. NQ and NQ factors were different according to the general characteristics and home background characteristics of the subjects. The mean scores for the moderation factor was significantly lower as the eating out frequency increased (p<0.001). The mean scores for balance, moderation, and regularity factors were significantly higher, with higher parents educational level. It is necessary to choose diverse side dishes, vegetables and also foods with balanced nutrition when eating out.

• Journal of the Korean earth science society
• /
• v.32 no.5
• /
• pp.514-520
• /
• 2011

As homework, a total of 32 seventh grade science-gifted students were asked to observe the moon at daily intervals for one month duration. They were also asked to take the photos and to record relevant variables in a given format. The purpose of the task was to investigate what students thought, as they observed the moon. The results show that students paid attention mainly to the position of the moon relative to other variables such as the date in the lunar calendar, the observer's position on the earth, and the position of the sun. Overall students' response implied that students did not observe the lunar phase in relation with relevant variables. Some reponses from students show common misconceptions such as the cause of the lunar phase to reflect the shadow of the earth. However, some responses reveal students' idea that has been rarely reported in the previous researches. For example, some students drew the moon to revolve in the opposite direction. Significant number of students drew the sun's position to be due west before the full moon and due east after the full moon. Few students recognized the relation between the time of observation and observer's position on the earth. The results of current research suggest that not only the education but also the research needs to be expanded to consider informal environment such as the actual field conditions.

• Tunnel and Underground Space
• /
• v.26 no.1
• /
• pp.46-58
• /
• 2016

In this study, a LIDAR laser scanner was used to scan a rock slope around Mt. Gwanak and to produce point cloud from which directional information of rock joint surfaces shall be extracted. It was analyzed using two different algorithms, i.e. Ball Pivoting and Wrap algorithm, and four sampling intervals, i.e. raw, 2, 5, and 10 cm. The results of Fuzzy K-mean clustering were analyzed on the stereonet. As a result, the Ball Pivoting and Wrap algorithms were considered suitable for extraction of rock surface orientation. In the case of 5 cm sampling interval, both triangulation algorithms extracted the most number of the patch and patched area.

• Conservation Science in Museum
• /
• v.23
• /
• pp.31-48
• /
• 2020

Conservation treatment of stone cultural properties in the open air is mainly conducted by companies specialized in conservation treatment. This study presents cases of conservation treatment of stone cultural properties housed outdoors in Seoul, including the Three-story Stone Pagoda at Nakseongdae in Gwanak-gu. The present condition of and damage to stone cultural properties are investigated and the materials and techniques used for conservation treatment are presented. The contamination on the surface of stone cultural properties located in downtown areas shows features specific to the related areas, meaning each case requires tailored conservation techniques. This study is expected to serve as reference for future conservation treatment of stone cultural properties in Seoul as well as others in museum collections exhibited outdoors. It is hoped that the cases presented in this study can become widely known to people in charge of conservation treatment in the private and public sectors to improve the quality of conservation treatment applied to stone cultural properties.