• Journal of the Korean Society of Food Culture
• /
• v.11 no.3
• /
• pp.305-316
• /
• 1996

The purpose of this study was to find out how much they have several aspects of food related knowledge and eating behaviors of high school students in Sungnam area. The self-administrated questionnaire was used. The result were as follows: 1. The average height of boys and girls was $172.6{\pm}0.7$ cm and $156.3{\pm}1.5$ cm respectively. The average weights of them were $62.4{\pm}0.5$ kg (male) and $47.2{\pm}0.8$ kg (female). BMI (Body Mass Index) of them were $20.74{\pm}0.14$ (male), $18.82{\pm}0.28$ (female). The average age is 16.7 years old. 2. The 66.5% of the subjects were spent more than one-third of their pocket money in buying on light meals during three times a week. There were significant differences between income level of family. Boys spent more money on each meal than girls. And significant differences were also obserbed by their residence area and Bundang residences spent more in buying snacks. 3. The rate of skipping meals was 51.2% in boys compared with 68.0% in girls. The frequencies of buying snacks instead of main meal were high in girls. Time limits in eating may possibly be the main reason for skipping meals (59.8%), especially in the morning. Skipping a breakfast becomes general eating habits in high school students, because of pressure for time to go to school. 4. It is required that parents should be taught to prepare balanced lunch box for their children because the rate of students who prepared two lunch boxes are 49.4%. 5. The students took snacks once or twice a day. They usually bought snacks in school concessions (51.8%) and they selected items of snack instinctivly. The girls ate snacks during lunch break time (31.7%) and after dinner (23.6%). Boys ate snacks after dinner (29.1%). Preference of foods were different by sex. Boys preferred bread (31.7%), milk and otherdairy products (80.8%), cola and soda (42.0%) as their snacks between meals. Girls selected biscuit, chip, beverage, coffee as their snacks, frequently. 6. BMI value of the group who ate between meals more than three times a day was lower $(18.78{\pm}0.65)$ than that of the group who ate nothing between meals $(20.71{\pm}3.79)$. 7. As for the nutritional knowledge, the students generally had higher correct rate of answer about which nutritive components of food has (76.6%). But they had lower knowledge on questions of nutritive values in food (10.6%). There was a meaningful relation between favorite food and nutritional knowledge. In conclusion, there were some problems on nutritional knowledge and eating habits among the high school students. Therefore, it was required that girls should be learned to recognize the importance of breakfast and needed to select balanced meals and snacks. And it was required that the nutrition education should be complemented to motivate and improve practical eating behaviors.

• The Journal of the Convergence on Culture Technology
• /
• v.5 no.4
• /
• pp.79-85
• /
• 2019

'Experiments in Art and Technology' Group was established in the mid-20th century, and then developed the larger interdisciplinary experiments into the range of art world and its outside field. The motive power of group's activities was the collaboration between artists and engineers traversing the boundary between old different disciplinary conventions. E.A.T was officially launched in 1967 by the engineers Billy $Kl{\ddot{u}}ver$ and Fred Waldhauer and the artists Robert Raushenberg and Robert Whitman. They performed various possibility of material, technology, and engineering available to contemporary art. By reflecting the function of art and technology in society, eventually they developed the methodology of new aesthetics which had organic relationship with contemporary world. In this sense, this research have its academic significance. This paper firstly examined the socio-cultural context of emerging the E.A.T. group as a representative model for convergent practice, and verified the fact that the collaboration between artists and engineers had produced the expansion of artistic expression as well as new relationship among art, engineering, and society by considering E.A.T's various projects. Therefore, I will refer the E.A.T. group as an exemplary model for concrete method of collaboration that contemporary discourses about convergence need.

• Design Convergence Study
• /
• v.15 no.2
• /
• pp.17-35
• /
• 2016

Along with popularization of smart phone and routinization of social network service, enterprises are using several social network services as a marketing channel to raise brand awareness and conduct PR. Enterprises have been utilizing an element of 'Gamification' representing a functional aspect and emotional pleasure of a game in order to attract users' attention and increase their voluntary participation since the early social network service marketing. However, social network service system contains functional roles of Gamification components rather than they function separately. Hence, this research intends to examine Gamification elements of social network service and characteristics occurred when enterprise uses several social network services as a marketing channel. Besides, it aims at suggesting a marketing guideline for Gamification based on social network that may induce users' interest and increase an immersion effect. Firstly, this study examined concepts and characteristics of social network service and Gamification centered on literature research. Secondly, it summarized a game mechanics, dynamics and a fun type of Gamification components. Thirdly, based on theoretical research, it collected Gamification marketing cases of 5 enterprises including 'Coca Cola Korea', 'Lotte Mart', 'Canon Korea', "Kolon Sports' and 'Uniqlo Korea' that utilize more than 3 of 4 social network services including 'Kakao Story', 'Band', 'Facebook' and 'Instagram' used the most in our nation, analyzing characteristics of Gamification marketing and deriving a suggestion. Finally, it suggested a guideline for Gamification and social network service to build a foundation for a Gamification marketing plan through social network service.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.19 no.2
• /
• pp.109-117
• /
• 1986

For the purpose of obtaining basic data which can be applied to processing of retort pouched shellfishes, retort pouched seasoned ark shell, Anadara broughtonii, was prepared. The frozen ark shell was thawed and seasoned with a mixed seasoning powder prepared with $10.0\%$ of sorbitol, $2.0\%$ of table salt and $0.5\%$ of monosodium glutamate at $5^{\circ}C$ for 10 hours, and then dried at $45^{\circ}C$ for 4 hours. The dried seasoned ark shell was coated with $1.0\%$ sodium alginate solution, dried with cola air blast for 2 hours and then vacuum-packed in the laminated plastic film bag (polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally sterilized up to Fo=6.0 in hot water circulating retort at $121^{\circ}C$ for 10 minutes. The major fatty acids of raw ark shell and retort pouched seasoned ark shell products were 16:0, 20:5, 22:6, 18:0 and 18:3, and predominant free amino acids of those were lysine, arginine, glycine, alanine, glutamic acid and leucine. In nucleotides and its related compounds of raw ark shell and retort pouched seasoned ark shell products, the most abundant one was AMP, and total extract-N of those was chiefly consisted of free amino acids, betaine and nucleotide and its related compounds. During the processing procedure such as drying and sterilization, unsaturated fatty acids slightly decreased while saturated fatty acids increased, and total extract-N content decreased about a half. From the results of chemical and microbial experiments during storage, it was concluded that the products could be preserved in a good condition for 100 days at room temperature, and their duality could be improved by the coating treatment of sodium alginate solution.

• The Journal of Korean Academy of Prosthodontics
• /
• v.58 no.1
• /
• pp.1-6
• /
• 2020

Purpose: This study evaluated color stability of Dentca 3D-printed denture teeth, in comparison to color stabilities of four conventional types of denture teeth, upon being immersed in various colorants. Materials and methods: Four types of conventional prefabricated denture teeth (Surpass, GC, Artic 6, Heraeus Kulzer, Premium 6, Heraeus Kulzer, Preference, Candulor), 3D-printed denture teeth (Dentca); and Z250 (Filtek Z250, 3M ESPE) were prepared for testing. The samples were immersed in erythrosine 3%, coffee, cola, and distilled water (DW) at 37℃. Color change (ΔE) was measured by spectrophotometer before immersion and at 7, 14, and 21 days after immersion. One-way analysis of variance was performed along with Tukey's honestly significant difference multiple comparisons test (P<.05). Results: No great difference was observed between the color change of Dentca denture teeth and that of conventional denture teeth in most cases (P>.05). The color change of Dentca denture teeth immersed in erythrosine 3% was greater than that of Surpass (ΔE = 0.67 ± 0.25) after 1 week; Artic 6 (ΔE = 1.44 ± 0.38) and Premium 6 (ΔE = 1.69 ± 0.35) after 2 weeks; and Surpass (ΔE = 1.79 ± 0.49), Artic 6 (ΔE = 2.07 ± 0.21), Premium 6 (ΔE = 2.03 ± 0.75), and Preference (ΔE = 2.01 ± 0.75) after 3 weeks (P<.05). Conclusion: A color change was observed in Dentca denture teeth when immersed in some colorants; however, the maximum value of ΔE for Dentca denture teeth was within the clinically acceptable range.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.31 no.3
• /
• pp.381-390
• /
• 2004

The purpose of this in vitro study was to investigate the effects of Nd:YAG laser irradiation and fluorides on acid drink demineralized enamel. The materials were 30 freshly extracted permanent premolars with intact smooth enamel surfaces. They were demineralized with Coca-cola at $37^{\circ}C$ for 12hours and then irradiated by Nd:YAG laser with 6W power, $50mJ/cm^2$ energy density, and 20Hz pulse repetition. After laser irradiation, teeth were treated by three kinds of fluorides; (1)0.05% NaF fluoride solution (2)1.23% APF gel and (3)0.1%F fluoride varnish, microhardness(VHN) and Diagnodent scores were measured and the surfaces of each treated specimens were also observed with SEM under 1500 magnification. The results were as follows: 1. In the change of microhardness(VHN), it decreased to 34.68% from the initial micrhardness, increased to 78.37% after laser irradiation and increased to 82.62% after fluoride treatment, there were significant differences except when it was irradiated and treated with fluoride(P<0.05). 2. In the change of Diagnodent scores, it was decreased to 28.08% from the initial scores after demineralization, and then increased to 59.81% after laser irradiation, and increased to 82.17% after fluoride treatment. Scores were different significantly between the scores of initial, demineralization, laser irradiation and fluoride treatment(P<0.05). All the scores were not different significantly between fluoride types. 3. SEM observation showed that the lased enamel surfaces after demineralization were thermally degenerated and showed molten lava-like appearance and crater with cracks and many microholes.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.33 no.2
• /
• pp.262-268
• /
• 2006

The purpose of this in vitro study was to evaluate the remineralizing effects of Nd : YAG laser irradiation and fluorides application on primary tooth enamel eroded by acidic drink. The materials were 30 sound primary teeth with intact smooth enamel surfaces. They were demineralized with Coca-cola at $37^{\circ}C$ for 12 hours and then irradiated by Nd: YAG laser with 6W power, $50mJ/cm^2$ energy density. and 20Hz pulse repetition. After laser irradiation, teeth were treated by three kinds of fluorides : (1) 0.05% NaF solution, (2) 1.23% APF gel and (3) 0.1% fluoride varnish. Diagnodent scores and microhardness (VHN) were measured before and after the each treatment. The results were as follows: 1. Diagnodent scores decreased to 23.51% from the initial after demineralization, and then increased to 37.37% after laser irradiation, and to 51.34% after fluoride treatment. There were significant differences between the total scores of initial, demineralization, laser irradiation and fluoride treatment (P<0.05). There was no significant difference between scores after fluoride treatment according to fluoride types. 2. Microhardness(VHN) decreased to 33.58% from the initial after demineralization and then increased to 43.99% after laser irradiation, and to 51.38% after fluoride treatment. There were significant differences between the total scores of initial, demineralization, laser irradiation and fluoride treatment (P<0.05). There was no significant difference between scores after fluoride treatment according to fluoride types.

• Journal of The Korean Association For Science Education
• /
• v.33 no.2
• /
• pp.425-443
• /
• 2013

We developed problem-solving type inquiry learning programs reflecting scientists' research process and analyzed the activities of science-gifted high school students, and the understanding and the effects of the programs after implementation in class. For this study, twelve science-gifted students in the 10th grade participated in the program, which consisted of three different modules - making a cycloidal pendulum, surface growth, and synchronization using metronomes. Diet Cola Test (DCT) was used to find out the effect on the improvement of the ability to design experiments by comparing pre/post scores, with a survey and an interview being conducted after the class. Each module consisted of a series of processes such as questioning the phenomenon scientifically, designing experiments to find solutions, and doing activities to solve the problems. These enable students to experience problem-solving type research process through the program class. According to this analysis, most students were likely to understand the characteristics of problem-solving type inquiry learning programs reflecting the scientists' research process. According to the students, there are some differences between this program class and existing school class. The differences are: 'explaining phenomenon scientifically,' 'designing experiments for themselves,' and 'repeating the experiments several times.' During the class students have to think continuously, design several experiments, and carry them out to solve the problems they found at first. Then finally, they were able to solve the problems. While repeating this kind of activities they have been able to experience the scientists' research process. Also, they showed a positive attitude toward the scientists' research by understanding problem-solving type research process. These problem-solving type inquiry learning programs seem to have positive effects on students in designing experiments and offering the opportunity for critical argumentation on the causes of the phenomena. The results of comparing pre/post scores for DCT revealed that almost every student has improved his/her ability to design experiments. Students who were accustomed to following teacher's instructions have had difficulty in designing the experiments for themselves at the beginning of the class, but gradually, they become used to doing it through the class and finally were able to do it systematically.

• Journal of dental hygiene science
• /
• v.10 no.6
• /
• pp.451-457
• /
• 2010

It is well known that most of the beverages on sale contain acid. Among these beverages, one of the most typically purchased products is Coca-Cola ($Coke^{(R)}$), which affects the demineralization of the tooth enamel surface. However other beverages also affect the erosion of the tooth enamel surface. Therefore, the aim of this study was to observe the influence that acid containing beverages have upon the tooth enamel surface. In this study, 30 enamel specimens were obtained from extracted maxillary third molars without cracks. The study measured the pH concentrations and the Ca and P concentration levels of the acidic beverages. The control without exposure was kept in distilled water, and each enamel specimen was stored for 30-min, 60-min, and 120-min. The erosion effect of the enamel surface was observed by SEM. The results obtained from this study can be summarized as follows: 1. The pH concentration of acidic beverages, without milk, was 3.105 on average. The beverages eroded the enamel surface and the erosion degree was determined by the pH concentration of beverages. 2. The erosion degree significantly increased by as the exposure time increased. The difference in the erosion degree between the 30-min group and the 60-min and the 120-min group was significant, but the erosion degree of the 120-min group was significantly less than that of the initial group. 3. When compared with the beverages containing similar pH concentrations, the demineralization degree of the beverages containing higher concentrations of Ca and P was lower.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.1
• /
• pp.1-12
• /
• 2010

The aim of this study was to evaluate the preventive effect of commercially available anticariogenic products, specifically, the tooth cream containing Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP), fluoride varnish and low-level fluoride mouthrinse on enamel erosion induced by carbonated beverage in a short period of time. Enamel specimens were treated as follows and were then kept in artificial saliva for 24 hours followed by further processing by alternately soaking them in Cola beverage and in distilled water for 1 minute each five times. Group 1: control group (no treatment) Group 2: tooth cream with CPP-ACP Group 3: fluoride varnish (1,000 ppm F) Group 4: low-level fluoride mouthrinse (227 ppm F) Group 5: fluoride varnish + tooth cream with CPP-ACP Group 6: low-level fluoride mouthrinse + tooth cream with CPP-ACP Microhardness and erosion depth were measured and the mineral loss of each specimen was evaluated by measuring the volumetric fluorescence change(${\Delta}Q$) against the stable fluorescent grid using quantitative light-induced fluorescence(QLF). The experiment lasted for 6 days repeated each day. The results were as follows: 1. The microhardness was increased as follows: Group $1{\leq}2{\leq}4$<6<$3{\fallingdotseq}5$. 2. The mean erosion depth was increased as follows: Group $5{\fallingdotseq}3$<6<$4{\fallingdotseq}2{\fallingdotseq}1$. 3. The ${\Delta}Q$ was increased as follows: Group $1{\fallingdotseq}2{\leq}4{\leq}6{\leq}3{\fallingdotseq}5$. The decrement of ${\Delta}Q$ was similar between group 1 and 2, group 4 and 6 and group 3 and 5. 4. The ${\Delta}Q$ showed positive correlation with microhardness (r=0.96, p<0.05), while it was negatively correlated to erosion depth (r=-0.96, p<0.05).