• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.3
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• pp.183-195
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• 2020

Purpose: The purpose of this study is to compare the flexural strength of CAD/CAM denture base resins with conventional denture base resins based on their thicknesses. Materials and Methods: For the conventional denture base resins, Lucitone 199^® (C-LC) was used. DIOnavi - Denture (P-DO) and DENTCA Denture Base II (P-DC) were taken for the 3D printing denture base resins. For the prepolymerized PMMA resins, Vipi Block Gum (M-VP) and M-IVoBase^® CAD (M-IV) were used. The final dimensions of the specimens were 65.0 mm x 12.7 mm x 1.6 mm / 2.0 mm / 2.5 mm. The 3-point bend test was implemented to measure the flexural strength and flexural modulus. Microscopic evaluation of surface of fractured specimen was conducted by using a scanning electron microscope (SEM). After testing the normality of the data, one-way ANOVA was adopted to evaluate the differences among sample groups with a significance level of P = 0.05. The Tukey HSD test was performed for post hoc analysis. Results: Under the same thicknesses, there are significant differences in flexural strength between CAD/CAM denture base resins and conventional denture base resins except for P-DO and C-LC. M-VP showed higher flexural strength than conventional denture base resins, P-DC and M-IV displayed lower flexural strength than conventional denture base resins. Flexural modulus was highest in M-VP, followed by C-LC, P-DO, P-DC, M-IV, significant differences were found between all materials. In the comparison of flexural strength according to thickness, flexural strength of 2.5 mm was significantly higher than that of 1.6 mm in C-LC. Flexural strength of 2.5 mm and 2.0 mm was significantly higher than that of 1.6 mm in P-DC and M-VP. In M-IV, as the thickness increases, significant increase in flexural strength appeared. SEM analysis illustrates different fracture surfaces of the specimens. Conclusion: The flexural strength of different CAD/CAM denture base resins used in this study varied according to the composition and properties of each material. The flexural strength of CAD/CAM denture base resins was higher than the standard suggested by ISO 20795-1:2013 at a thickness of 1.6 mm or more though the thickness decreased. However, for clinical use of dentures with lower thickness, further researches should be done regarding other properties at lower thickness of denture base resins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1467-1474
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• 2012

The purpose of study was to introduce menus consisting of traditional local foods consumed in Busan, Korea. Five different types of formal meal menus with three side dishes and five different types of informal meal menus of which the main dish was not cooked rice were developed. Scores for the menu evaluations of formal and informal meals were higher than 7.9 (mean score of 6 category) on a 9.0 scale, suggesting that the menus were well constituted in terms of 'repeated use of ingredients and cooking methods', 'balance between main and side dishes', 'frequency of usage of local products', 'nutritional balance', 'variety of dishes', and 'popularization'. Nutritional values of menus were compared with those of the KDRI for men aged 30~49 years old. All ten menus reflected a low calorie, high protein, and high fiber diet. Mineral contents (Ca, Fe, Zn, K, and Na) of the above 10 menus were higher than those of the KDRI. On the other hand, vitamin contents slightly differed according to meal type due to limited fresh vegetable usage in the winter season. Vitamin A, B ($B_1$, $B_2$, niacin, $B_6$), C, folic acid, and E contents in the five informal menus were found to be proper or greater than those of the KDRI. However, for the formal meal menus, all vitamin contents except that of vitamin A in menu type I was lower than that of the KDRI. Content of vitamin C in menu type V was approximately 50% of that of the KDRI. The most preferred formal menu was consisted of Ogokbap, Boreumjijimi, Dongchimi, Namul (nine varieties), Gaksaeksanjeok (Shark/Daegu/Gunso), and Gimgui. And that for informal menu was consisted of Honghapjuk, Baechu kimchi, Dongchimi, Miyeokseolchi, Kodari jorim, and Neulgeun hobakjeon. Suggestions for providing more fresh vegetables or fruits for certain types of meals (formal meal type V) were offered. Additionally, pre-preparation of sea products were required to reduce Na contents.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.53-60
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• 2009

Purpose: Primary osteoarthritis on the elbow is the result of the growth of osteophytes and contracture of the capsule. It often causes disability on joint motion and pain while exercising. As arthroscopy has developed, the arthroscopic diagnosis and treatment of the elbow have recently become more generalized as well. Therefore, we like to report on arthroscopy for treating elbow arthritis and its results. Materials and Methods: This study includes 23 cases of elbow arthritis that were seen between 2005 June to 2007 June and these patients didn't response to conservative treatment. From this we excluded 18 cases that underwent arthroscopic surgery and among these 18 cases, 6 cases underwent ulnar nerve transfer. The average observation time was 21.3 months and the average age was 48.4 years (range: 22-66 years). The pre and post operative pain was evaluated with using the Visual Analogue Scale (VAS) and functional evaluation was done with using the Mayo elbow Performance Score (MEPS) with the range of joint motion. Results: The VAS score at the last follow up was significantly decreased from 3.4 to 1.9 compare to the preoperative score. The range of joint motion was improved by 25 (0-40) to 8.5 (0-20) in extension and 101.7 (80-140) to 125.2 (85-140) in flexion (p<0.05). The MEPS always showed significant improvement by showing an increase from 65.4 (40-85) to 87.9 (55-100). However, 3 cases showed a decreased range of motion after the operation. One case showed ulnar nerve symptoms after surgery. Conclusion: An arthroscopic procedure can treat the pathologic processes associated with arthritis of the elbow and it was safe and effective in this series.

• Journal of Intelligence and Information Systems
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• v.21 no.1
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• pp.99-118
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• 2015

Object-oriented programming languages have been widely selected for developing modern information systems. The use of concepts relating to object-oriented (OO, in short) programming has reduced efforts of reusing pre-existing codes, and the OO concepts have been proved to be a useful in interpreting system requirements. In line with this, we have witnessed that a modern conceptual modeling approach supports features of object-oriented programming. Unified Modeling Language or UML becomes one of de-facto standards for information system designers since the language provides a set of visual diagrams, comprehensive frameworks and flexible expressions. In a modeling process, UML users need to consider relationships between classes. Based on an explicit and clear representation of classes, the conceptual model from UML garners necessarily attributes and methods for guiding software engineers. Especially, identifying an association between a class of part and a class of whole is included in the standard grammar of UML. The representation of part-whole relationship is natural in a real world domain since many physical objects are perceived as part-whole relationship. In addition, even abstract concepts such as roles are easily identified by part-whole perception. It seems that a representation of part-whole in UML is reasonable and useful. However, it should be admitted that the use of UML is limited due to the lack of practical guidelines on how to identify a part-whole relationship and how to classify it into an aggregate- or a composite-association. Research efforts on developing the procedure knowledge is meaningful and timely in that misleading perception to part-whole relationship is hard to be filtered out in an initial conceptual modeling thus resulting in deterioration of system usability. The current method on identifying and classifying part-whole relationships is mainly counting on linguistic expression. This simple approach is rooted in the idea that a phrase of representing has-a constructs a par-whole perception between objects. If the relationship is strong, the association is classified as a composite association of part-whole relationship. In other cases, the relationship is an aggregate association. Admittedly, linguistic expressions contain clues for part-whole relationships; therefore, the approach is reasonable and cost-effective in general. Nevertheless, it does not cover concerns on accuracy and theoretical legitimacy. Research efforts on developing guidelines for part-whole identification and classification has not been accumulated sufficient achievements to solve this issue. The purpose of this study is to provide step-by-step guidelines for identifying and classifying part-whole relationships in the context of UML use. Based on the theoretical work on Meta-model Formalization, self-check forms that help conceptual modelers work on part-whole classes are developed. To evaluate the performance of suggested idea, an experiment approach was adopted. The findings show that UML users obtain better results with the guidelines based on Meta-model Formalization compared to a natural language classification scheme conventionally recommended by UML theorists. This study contributed to the stream of research effort about part-whole relationships by extending applicability of Meta-model Formalization. Compared to traditional approaches that target to establish criterion for evaluating a result of conceptual modeling, this study expands the scope to a process of modeling. Traditional theories on evaluation of part-whole relationship in the context of conceptual modeling aim to rule out incomplete or wrong representations. It is posed that qualification is still important; but, the lack of consideration on providing a practical alternative may reduce appropriateness of posterior inspection for modelers who want to reduce errors or misperceptions about part-whole identification and classification. The findings of this study can be further developed by introducing more comprehensive variables and real-world settings. In addition, it is highly recommended to replicate and extend the suggested idea of utilizing Meta-model formalization by creating different alternative forms of guidelines including plugins for integrated development environments.

• Journal of Chest Surgery
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• v.31 no.9
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• pp.861-866
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• 1998

Background: Pulmonary atresia (PA) with ventricular septal defect has various morphology of pulmonary arteries and pulmonary blood flow sources, so pulmonary arterial hypoplasia and arborization abnormality make this anomaly difficult to manage surgically. In cases associated with juxtaductal stenosis, we evaluated the change of the pulmonary arterial and juxtaductal stenotic site after shunt operations, and would like to find useful information in surgical planning and methodology of these patients. Material and Method: Among 59 cases diagnosed as PA with ventricular septal defect associated with juxtaductal stenosis, 29 cases who had cardiac catheterization before and after shunt operation were selected from July, 1991 to July, 1996. In 10 cases of right shunt operation(Group I) and 19 cases of left shunt operation (Group II), the diameters of the descending aorta, both pulmonary arteries, and the juxtaductal stenosis site were measured before and after the shunt operation. Result: In both Group I and II, the pre- and postoperative ratio of diameters of the ipsilateral pulmonary artery to the descending aorta was from 0.78${\pm}$0.31 units to 1.01${\pm}$0.26 units and from 0.67${\pm}$0.18 units to 0.84${\pm}$0.27 units respectively, showing a signigicant increase. The contralateral pulmonary artery index was increased from 0.92${\pm}$0.28 units to 1.05${\pm}$0.15 units and from 0.94${\pm}$0.27 units to 1.08${\pm}$0.37 units respectively, but could not be confirmed statistically. In both groups, the change of juxtaductal stenosis showed an aggravating tendency but of no statistical significance from 0.43${\pm}$0.27 units to 0.39${\pm}$0.25 units and from 0.32${\pm}$0.10 units to 0.30${\pm}$0.16 units respectively, and we experienced 2 total obstruction in Group II. Because the increased pulmonary blood flow by shunt operation has a favorable effect to the pulmonary arterial growth, the shunt operation is a recommended treatment in patients with hypoplastic pulmonary arteries. But in PA with ventricular septal defects, the change of juxtaductal stenosis is very important. In conclusion, the growth of ipsilateral (shunt site) pulmonary artery was promoted by shunt operation, but there is a tendency for the juxtaductal stenosis to be aggravated. And we experienced 2 total obstruction in Group II. Conclusion: Thus, in cases operated with shunt method, much careful postoperative follow up study including angiographic evaluation is needed, and after the shunt operation on the side of pulmonary artery associated with juxtaductal stenosis, early precise planning for total correction is recommended.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.1
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• pp.35-42
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• 2018

Objectives: The objectives of this study are to research the usage characteristics of asbestos-containing building materials and to conduct exposure risk assessment by applying no. 2016-230 "Methods of Risk Assessment of Asbestos-Containing Buildings" from the Ministry of Environment. Methods: One hundred buildings located in the Seoul and Gyeonggi-Incheon area were chosen, with 29 in Seoul, 20 in Incheon, and 51 in Gyeonggi-do Province. The year of construction was divided between three buildings in the 1970s, 11 buildings in the 1980s, 42 buildings in the 1990s, and 44 buildings in the 2000s. The bulk samples were analyzed by using a polarizing microscope after a pre-process using a stereomicroscope in a hood with an HEPA filter. This study defined ACMs(asbestos-containing materials) as asbestos when the content percentage was over 1% in the analysis result. Methods and standards of risk assessment of asbestos-containing building materials were conducted by refering to no. 2016-230 "Method of Risk Assessment of Asbestos-Containing Buildings" from the Ministry of Environment. The risk of exposure to ACMs was rated by a score based on three categories(high, middle, low risk of asbestos exposure). Results: In this study, 30 of the 100 buildings and 36 of the 416 bulk samples(8.6%) were found to have had asbestos. Asbestos was detected at a high rate, in 18 out of 42, in buildings constructed in the 1990s and at the lowest rate(7 out of 44) for buildings constructed in the 2000s. As a result of the evaluation according to no. 2016-230 "Method of Risk Assessment of Asbestos-Containing Buildings" of the Ministry of Environment, the risk assessment level of two asbestos-containing building materials was found to be "Medium", and 28 buildings materials were found to be at the "Low" level. Conclusion: As asbestos is regulated by the government, it is required to conduct active management and implemention by introducing methods of risk assessment of asbestos exposure that are supported by data from various situations. In the case of buildings owned by individuals, building owners should be aware of the risk of exposure to asbestos.

• Journal of Gifted/Talented Education
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• v.13 no.4
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• pp.65-94
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• 2003

The purpose of this study is to acquire the information on the current situation of students' selection process in order to renovate the system of picking up the students. As a first step of the study, we examined the validity of the factors of the single-out system such as qualification and the process for the application and the standards and proceeding of the selection. Then we analysed the result of the entrance examination of Hansung Science Highschool in 2002. The analysis was on the correlation between the result of entrance examination and the achievement in the school and the decision of the course after graduation. To know on the achievement of the students, we investigated the records of regular tests and asked the teachers' opinion in math and science classes. As a result, we gained the following points: First, the present single-out system has a danger of excluding students who are much talented in science and math field because it is based on students' achievements in middle schools; Second, the new selection system should consider the character and attitude of the applicants in addition to their knowledge; Third, the continuous observation of the teacher in middle school should be an important factor of the picking up system; Fourth, more questions requiring divergent thinking ability and inquiry skill should be developed as selective examination question. Also examination questions should cover the various contents from mathematics to science, and do not affect pre-learning; Finally, the system of present letting all students stand in one line should be changed into that of letting students in various lines. We can consider using multi-step selection system.

• The Korean Journal of Blood Transfusion
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• v.23 no.2
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• pp.127-135
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• 2012

Background: Despite modern advances in laboratory automated medicine, work-process in the blood bank is still handled manually. Several automated immunohematological instruments have been developed and are available in the market. The IH-1000 (Bio-Rad Laboratories, Hercules, CA, USA), a fully automated instrument for immunohematology, was recently introduced. In this study, we evaluated the performance of the IH-1000 for ABO/Rh typing and irregular antibody screening. Methods: In October 2011, a total of 373 blood samples for ABO/Rh typing and 303 cases for unexpected antibody screening were collected. The IH-1000 was compared to the manual tube and slide methods for ABO/Rh typing and to the microcolumn agglutination method (DiaMed-ID system) for antibody screening. Results: For ABO/Rh typing, concordance rate was 100%. For unexpected antibody screening, positive results for both column agglutination and IH-1000 were observed in 10 cases (four cases of anti-E and c, three of anti-E, one of anti-D, one of anti-M, and one of anti-Xg) and negative results for both were observed in 289 cases. The concordance rate between IH-1000 and column agglutination was 98.7%. Sensitivity and specificity were 90.9% and 99.3%, respectively. Conclusion: The automated IH-1000 showed good correlation with the manual tube and slide methods and the microcolumn agglutination method for ABO-RhD typing and irregular antibody screening. The IH-1000 can be used for routine pre-transfusion testing in the blood bank.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.562-581
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• 2018

This study was designed to predict the changes in species richness of plants under the climate change in South Korea. The target species were selected based on the Plants Adaptable to Climate Change in the Korean Peninsula. Altogether, 89 species including 23 native plants, 30 northern plants, and 36 southern plants. We used the Species Distribution Model to predict the potential habitat of individual species under the climate change. We applied ten single-model algorithms and the pre-evaluation weighted ensemble method. And then, species richness was derived from the results of individual species. Two representative concentration pathways (RCP 4.5 and RCP 8.5) were used to simulate the species richness of plants in 2050 and 2070. The current species richness was predicted to be high in the national parks located in the Baekdudaegan mountain range in Gangwon Province and islands of the South Sea. The future species richness was predicted to be lower in the national park and the Baekdudaegan mountain range in Gangwon Province and to be higher for southern coastal regions. The average value of the current species richness showed that the national park area was higher than the whole area of South Korea. However, predicted species richness were not the difference between the national park area and the whole area of South Korea. The difference between current and future species richness of plants could be the disappearance of a large number of native and northern plants from South Korea. The additional reason could be the expansion of potential habitat of southern plants under climate change. However, if species dispersal to a suitable habitat was not achieved, the species richness will be reduced drastically. The results were different depending on whether species were dispersed or not. This study will be useful for the conservation planning, establishment of the protected area, restoration of biological species and strategies for adaptation of climate change.

• Korean Journal of Poultry Science
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• v.46 no.3
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• pp.137-154
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• 2019

This study was conducted to develop and compare Samgyetang broth from extract of pre-treated chicken feet. Chicken feet were subjected to non-heating (control), heating at $70^{\circ}C$ for 12 h in a hot air dryer, and heating at $180^{\circ}C$ for 1 h in an oven. The heat-treated chicken feet were extracted at $121^{\circ}C$ for 1 h and 2 h, respectively. The extract was placed in a pouch with whole chicken carcass ($470{\pm}10g$). The sealed Samgyetang retort was made according to the industrial method. The pH of the extract from preheated chicken feet was lower than that extracted from fresh chicken feet. The Thiobarbituric Acid Reactive Substances (TBARS) value of the preheated chicken feet extract was significantly lower (P<0.05) than that of fresh chicken feet extract, but there were no significant differences among the broths. As the extraction time increased, the pH and TBARS value decreased in the extract (P<0.05) but increased in the broth (P<0.05). According to the sensory evaluation test, the extract from 1 h hot air heating and drying was significantly better in appearance, aroma, and overall preference than the other treatments (P<0.05). The GC-MS results showed that benzaldehyde and benzothiazole, which are widely known to give meat and nuts flavor, were detected in those treatments (P<0.05). The Samgyetang broths prepared from 1 h hot air heating and drying extract were significantly higher in the overall acceptability according to the sensory test (P<0.05). In summary, the quality of retort Samgyetang broth can be improved by adding chicken feet extract which is subjected to heating and drying for 1 h.