• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.370-377
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• 2018

Although the frequency of composite resin restoration in children is gradually increasing, there are insufficient researches about the rate of composite resin repair in children. The purpose of this study was to evaluate the repair rate of composite resin restorations in the permanent first molar in children under 12 years old. This study retrospectively analyzed 169 children treated with composite resin restoration in the permanent first molar from May 2014 to April 2015. According to the location of the tooth, the repair rate was higher in the mandible than maxilla and in the left than right. In the classification of restoration, the repair rate was the highest in the class II cavity, and the repair rate was the lowest in the restoration of the occlusal surface only. Repair rate in two years was 14.8%, and repair hazard ratio decreased with age. The most common reason of composite resin restoration replacement was the secondary caries (74.1%). Within the limits of study, the repair rate of children was higher than that of adult due to the characteristics of children. Therefore, dentists should understand these characteristics and try to reduce the repair rate of composite resin composite restorations.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.2
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• pp.18-26
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• 2000

Since the regulation of MSDS (Material Safety Data Sheets) had started from July 1996, employers were required to furnish MSDS for the chemicals in use in their workplace. However, many MSDS did not contain upright information for the chemicals, and they were not updated regularly, and were not written in the standard format required by the Industrial Safety and Health Act (ISHA). The purposes of this study were 1) to examine the reliability of MSDS for mixed solvents, 2) to provide reliable MSDS to employers or employees, 3) to find out any difficulties in implementing MSDS after the initiation, and 4) to promote regular MSDS updating and to ensure the reliability of MSDS for chemical manufacturers. To check the reliability of MSDS of mixed chemicals, 21 samples of mostly degreasing solvents were collected along with their MSDS from the work place. The samples were analyzed by gas chromatography-mass selective detector(GC-MSD). Their components were classified as saturated hydrocarbon, cyclic hydrocarbon, aromatics, and halogen containing hydrocarbon, and the amount of each class were measured. Manufacture's MSDS were compared with the actual composition of the collected samples, and further examined the reliability by checking whether the chemicals analyzed were included in the MSDS correctly. Finally, each item of MSDS was evaluated whether the MSDS correspond to the regulation required by ISHA. The results were following: 1) most of the degreasing solvents in MSDS were incorrect in their composition and contents, 2) the information in the MSDS including hazard classification, exposure level, toxicity, regulatory information were incorrectly provided, and 3) some MSDS did not disclose carcinogens in their MSDS. Continuous monitoring of MSDS was required to ensure reliability of MSDS. The Chemicals containing hydrocarbons from C10-C15 need to be tested to provide toxicity data. In addition, governmental support for providing correct MSDS was recommended to ensure reliability of MSDS. The MSDS regulation relating to the confidential business information may need to be revised to ensure reliability of MSDS.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.3
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• pp.29-43
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• 2012

This study evaluated 23 botanic gardens and arboretums under two main categories including professional group and operational group. As for professional group, the main difference between the functions of botanic gardens and arboretums was analyzed. In the case of operational group compared professional group respectively, on categories including importance of function and implementation, seeking to provide fundamental data of botanic gardens and arboretums by enhancing the quality of visitors and examining functional differences. The result of a difference in arboretums' function between professional and operational groups, the study analyzed the importance of botanic gardens and arboretums in terms of detailed categories such as research, education, collection, display, retention, and service for visitors. As a result, professional group showed retention 4.32>education 4.11>research 4.09>service for visitors 4.05, and operational group showed retention 3.70>service 3.52>education 3.41>research 3.37, indicating that both groups had retention as the most selected answer. Looking closely at the functions of the currently implemented detailed categories of botanic gardens and arboretums, such as research, education, collection, display, retention, and service for visitors, the study showed that 91.3% selected rare species and individual multiplication for research function, 78.3% chose education of natural ecosystem for children for education, 73.9% answered space for experiencing nature for display, and 73.9% also replied managon, diof rare species, reproduction, and retention of native plants' species for retention category, and service for visitors showed 95.7% for implementation. The study could not clearly point out the influence between predictors due to absence of an established comprehensive evaluation model. Also, it analyzed and reviewed comparison of functions of professional group and operational group, but in the future, it should conduct study on a systemic and objective classification of botanic gardens and arboretums to clearly examine the difference in views between groups, which also requires, at the same time, study on management policy of botanic gardens and arboretums or suggesting guidelines that suit types of forms, and also study on facilities and program development that can be applied to each class.

• Journal of Korean society of Dental Hygiene
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• v.6 no.4
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• pp.295-309
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• 2006

This study was conducted among 831 industrial workers in Gumi City in Gyung-Sang-Buk Do for the purpose of acquiring knowledge to improve quality of life though industrial workers' oral health promotion. Oral examination and questionnaire surveying were used to evaluate workers' oral health state and subjective health state and analyze their effect on quality of life. 1. The number of workers in the study were 831 in all; there were more males who accounted for 74.6%. 43.7% of the subject were 29 years old, accounting for the largest age group. Their academic backgrounds are 53.6% workers who graduated from high schools or lower educational institutions, and 46.4% workers who graduated from college or higher educational institutions. 80.7% of the subjects replied that their economic state belonged to the middle class. Their job classification indicates that 70.2% were working in production and engineering fields and that the seniority of 55.3% workers was less than 55.3%. 2. The result of evaluating the effects of oral health state on individual well-being and quality of life using OHIP indicates that younger people, singles(p<0.01) than the married, those in worse economic situation and those with shorter seniority(p<0.01) had higher effect of oral health state on quality of life. In addition, those whose health or oral health was not good (p<0.01), those with liked tough texture of food and snacks(p<0.05), those with more frequency of drinking(p<0.01) and those with more smoking tended to have higher effect of oral health state on daily life or quality of life. Besides, OHIP confirmed that oral health state is a measurement tool that can evaluate its effect on individual well-being and quality of life. The suggestion for future studies is to develop Korean style OHIP that can be used conveniently and efficiently by expanding the subject area up to the whole country and validating the samples gained from random sampling.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.253-264
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• 2009

The purpose of seed certification is to preserve the genetic purity and identity of seed varieties. This study is to provide information concerning seed certification procedures and certification standards of Kentucky bluegrass especially used in golf courses. We analyzed data from the seed certification standards of three states (Washington, Idaho and Oregon) in U.S.A. The certification processes both field inspection and laboratory requirement satisfying the minimum seed quality standards. The seed harvesting field must be propagated with the specified class of seeds and requires an adequate isolated distance from other crops. Moreover, the field should be clean and free from the objectionable weeds. The seed analysis tests include a germination rate, a percentage of pure seed, contents of other crop seed, weed seed, and inert matter. The certification standards of the certified seed and the sod quality seed showed general similarity in all three states. The certification standards of the sod quality seed should have less than 0.02% of maximum weed seed. The certified seed should have less than 0.3% of maximum weed seeds. Those certification standards of seed quality should guaranty the quality of turfgrass establishment of golf course.

• Journal of Chest Surgery
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• v.33 no.1
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• pp.32-37
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• 2000

Background: Reconstruction surgery of mitral valve regurgitation is now considered as an effective operative technique and has shown good long-term results. Although reconstructive surgery of mitral valve has been performed since 1970s, we have started only in early 1990s in full scale because of small number of the mitral regurgitation compared to mitral stenosis and lack of knowledge from the viewpoint of patients and physicians. Material and Method: From January 1992 to December 1996, 100 patients underwent repair of the mitral valve for mitral regurgitation with or without mitral stenosis in Seoul National University Hospital. 45(45%) of the patients were men and 55(55%) were women. The mean age was 39.9$\pm$14.4 years. The causes of the mitral regurgitation were rheumatic in 61, degenerative in 28 and others in 11. According to the Carpentier's pathological classification of mitral regurgitation 5 patients were type I. 55 patients were type II and 40 patients were type III. 7 patients underwent concomitant aortic valvuloplasty and 8 patients underwent aortic valve replacement. 7 patients underwent Maze operation or pulmonary vein isolation. Result: There were no operative death but 3 major operative complications: 2patients were postoperative low cardiac output syndrome(needed intra-aortic ballon pump support) and 1 patient was postoperative bleeding. There was one late death(1.0%) The cause of death was sepsis secondary to acute bacterial endocarditis. 3 patients required reoperation for recurred mitral regurgitation. There were no statistically significant risk factors for reoperation. The other 96 patients showed no or mild degree of mitral regurgitation 99 survivors were in NYHA functional class I or II. There were two throumboembolisms but no anticoagulation-related complications. Conclusion: We concluded that mitral valve repair could be performed successfully in most cases of mitral regurgitation even in the rheumatic and combined lesions with very low operative mortality and morbidity. The early results are very promising.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.296-305
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• 2013

For the purpose of evaluating the prevalence of malocclusion and self-esteem in adolescents, 1,380 middle-school students in the Yangsan area were surveyed by oral examination and questionnaires and the obtained results were as follows: The distribution of 1st molar occlusion by Angle's classification was 69.0, 19.4, 10.6% for Class I, II and III respectively. In the horizontal relationship, the prevalence of normal overjet and crossbite was 86.9% and 5.6% respectively whereas larger and extremely larger overjet was found in 6.6% and 0.8%. In the vertical relationship of anterior teeth, normal, deep overbite and openbite was shown in 94.1%, 4.7%, and 1.2%. For the midline discrepancy, the distribution of groups with 0~1 mm, 2~4 mm and over 5 mm was 98.2%, 1.4%, and 0.4%. Crowding only in the maxilla was found in 9.6%, while that only in the mandible and in both arches was 14.1% and 24.1% respectively. Spacing only in the maxilla was seen in 3.0%, while that only in the mandible and in both arches was 2.4% and 1.7% respectively. Significant difference in self-esteem was revealed in female and malocclusion groups of crossbite and openbite(p < 0.05).

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.2
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• pp.28-37
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• 2011

With growing concerns about healthy life recently, although the podiatry which deals with the whole area for diagnosis, treatment of foot and leg, and prevention has been widely interested, research in our country is not active. Also, because most of the previous researches in data analysis performed the quantitative approaches, the reasonable level of reliability for clinical application could not be guaranteed. Clinical data mining utilizes various data mining analysis methods for clinical data, which provides decision support for expert's diagnosis and treatment for the patients. Because the decision tree can provide good explanation and description for the analysis procedure and is easy to interpret the results, it is simple to apply for clinical problems. This study investigate rules of item of diagnosis in disease types for adapting decision tree after collecting diagnosed data patients who are 2620 feet of 1310(males:633, females:677) in shoes clinic (department of rehabilitation medicine, Chungnam National University Hospital). and we classified 15 foot diseases followed factor of 22 foot diseases, which investigated diagnosis of 64 rules. Also, we analyzed and compared correlation relationship of characteristic of disease and factor in types through made decision tree from 5 class types(infants, child, adolescent, adult, total). Investigated results can be used qualitative and useful knowledge for clinical expert`s, also can be used tool for taking effective and accurate diagnosis.

• Journal of the Korean Home Economics Association
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• v.25 no.3
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• pp.63-82
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• 1987

This is the forth consecutive study on the 'Standardization of Measurement for Korean Kitchen Work Centers and Cabinets for Future Design Criteria'. The purpose of the present research was (1) to classify homemakers' representative like styles related to the kitchen, (2) to examine homemakers' present concerns on the kitchen space, and (3) to investigate homemakers' desire and preference on the kitchen space. Twenty two hundred homemakers of upper and middle class residing in Seoul, Busan, Daegu, Incheon, Gwangju and Daejeon were selected for the survey and 1,843 among them were used for data analysis. Data were selected for the survey and 1,843 among them were used for data analysis. Data were analyzed using the SAS program package. The statistics used were frequency, percentage, mean, factor analysis, F-test, Duncan's multiple range test, X2-test, cluster analysis. Findings from the research as follows: (1) Four factors were found as indicaters of the life style; values on the household work, desire on social function of the kitchen, degree on cooperation of family members on the household work, and convenient management. It was noticeable that homemakers had positive responses in terms of desire on social function of the kitchen and degree on cooperation of family members on the household work. Homemakers' life styles related to the kitchen space were classified into 6 categories. (2) Relatively a few respondents answered that the kitchens were very well furnished. If, however, the economic conditions become better, substantial number of them wanted to invest for better kitchen following the one for living room. (3) It was found that most respondents preferred the arrangement of space, where dining and kitchen in one space, and a hard wall or soft treatment was between living and dining/kitchen area. (4) Many respondents desired pantry, utility and laundry area be near the kitchen or in the same space with it, thereby forming a utility core in a housing space.

• The korean journal of orthodontics
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• v.27 no.4 s.63
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• pp.523-538
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• 1997

In order to investigate TMD prevalence in malocclusion patients and to study its relationship with occlusal factors, 205 malocclusion patients (M67, F138, 6Y1M-46Y8M) were examined. The following examinations were carried out, Questionnaire personal history, TMD symptoms, and the associated factors Clinical examination : TMJ sound and maximum mouth opening Orthopantomogram : condyle abnormalities, length of Co'-Inc' and Co'-Go', ratio Co'- Inc'/ Co'-Go', and depth of antegonial notch Transcranial view limitation of anterior movement of condyle Model Angle classification, overjet, overbite, midline discrepancy, missing of posterior teeth, posterior crossbite, attrition of palatal cusp of maxillary molars, crowding/spacing The results could be summarized as follows, 1. The prevalence of TMD showed that Helkimo Anamestic Inder(Ai) 0 was $46.8\%$, Ai I was $22.0\%$, Ai II was $31.2\%$ and subjective symptoms increased with aging (p<0.001) and were frequent in females (p<0.05). 2. Flattening ($4.4\%$) was the most frequent condyle abnormality on Orthopantomogram, and $8.3\%$ of subjects showed some abnormalities on Orthopantomogram. 3. The cases with neck and shoulder pain (p<0.001), clenching, lip biting (p<0.01), and headache (p<0.05) showed higher scores of Ai. 4. Angle class II showed high frequency of condylar abnormalities on Orthopantomogram, and subjects whose palatal cusp of maxillary molars had been attrided had the tendency to show high hi scores (p<0.05). The other occlusal factors had nothing to do with the symptoms of TMD. 5. In the cases that 1)the value of Co'-Inc', Co'-Go' or Co'-Inc'/Co'-Go' were low or 2)the differences of Co'-Go' or Co'-Inc'/Co'-Go' between the right and the left were large, condylar abnormalities were frequently obserbed on Orthopantomogram.