• Journal of the Korean Society of Food Culture
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• v.10 no.2
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• pp.125-132
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• 1995

The purpose of this study was to survey several aspects of food-related knowledge, attitude and behavior of college students. Seven hundred male and female students in Seoul and Kyunggi-do area were randomly selected. And self-administered questionnaires were used. It was consisted of weight concern, nutritional knowledge, meal frequency, preference of snacks and psychological aspects of eating behaviors. The results were as followes: 1. The 66.5% of males and 87.9% of females were concerned about weight control. While 42% of male respondents wanted weight gain and 43% weight loss, most of female respondents wanted to lose weight. 2. The score of nutritional knowledge of males was significantly lower than the score of females (p<0.01). 3. The meal frequency was 3.4 times a day for male students and 3.6 for female students. But males showed higher frequency rates in three regular meals and females showed higher rates in snacking. Both male and female students considered that supper was the most important meal of the day and skipped breakfast frequently. 4. Fruits, beverage and milk were favorite snacking items for college students. But there were some differences in selection of food items by snacking time. Carbonated drinks and coffee were frequently selected by morning male and female snackers. Noodles and cookies were preferred by males and cookies were preferred by females as afternoon snack. Fruits were most often preferred by both males and females in the evening. 5. Physical tiredness and/or psychological factors were observed to influence the amount of food intake. After increase of food intake, male students felt more comfortable than female students who were afraid of their weight gain.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.4
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• pp.220-227
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• 2020

Objectives: Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder. These patients lose their teeth at a young age and are in need of prosthetic rehabilitation. The aim of this systematic review was to assess the success of dental implant placement in these patients. Materials and Methods: An electronic search was performed in PubMed Central, Scopus, and Web of Science using the keyword "Papillon-Lefèvre syndrome" AND "dental implant" OR "prosthodontics". Articles reporting implant placement in patients with PLS until July 2019 were included. Results: Assessment of the included 11 articles reporting 15 cases showed 136 implant placements in these patients. Implant failure occurred in 3 patients (20 implants). The peri-implantitis and failure rate was higher in the maxilla. Meta-analysis showed the probability of failure to be 7% (95% confidence interval [CI] 0%-31%) for maxillary implants and 2% (95% CI 0%-9%) for mandibular implants. The follow-up time ranged between 1 and 20 years. Healing after bone graft and implant placement in these patients was uneventful. Conclusion: Dental implants may be a viable treatment option for PLS patients. Implantation can help preserve alveolar bone if the patients' immunological and growing conditions are well-considered and proper oral hygiene and compliance with the maintenance program are continued.

• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.133-140
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• 2005

If a Player car precedes from start to the end or a fuzzy car wins every day during computer or racing games, most players will lose their interest in the games soon after several times. In order to solve this Problem and increase amusement at racing games, the more important thing than anything else is decide the ranking. In this thesis, in order to give amusement In racing games, the researcher made a fuzzy car and made it race with player cars. Because the preceding fuzzy car runs ahead of player cars, it can recognize their behaviors according to change of following player cars' speed and distance, and the fuzzy car changes its memory, but doesn't enforce actual behaviors. If the fuzzy car would make decision, it has to do behaviors to compete the ranking on the basis of the contracts it has memorized under the situation where a timer is awarded. In addition, although an accompanying fuzzy car has different contents of memory, it is operated in the same way as mentioned above. At the time of experiments, the researcher applied the actual value to the test program and drew result for ranking competition. In conclusion, the researcher could confirm that we can have modeling of various behaviors by means of the method using fuzzy logic rather than simple if-then method.

• Fire Science and Engineering
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• v.30 no.5
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• pp.54-59
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• 2016

Steel is a structural material that is inherently noncombustible. On the other hand, it has high thermal conductivity and the strength and stiffness of the material are reduced significantly when exposed to fire or high temperatures. Because the yield strength and modulus of elasticity of steel are reduced by 70% at $350^{\circ}C$ and less than 50% at $600^{\circ}C$, the load-carrying capacity of steel structure at high temperature rapidly lose. To be accepted as a fire-resisting construction, the fire test should be performed at the certificate authority. On the other hand, the fire test on a full-scale structure is limited by time, space, and high-cost. The analytical method was verified by a comparison with the fire test of H-section columns under compression and thermal analysis based on a finite element method using the ABAQUS program, and the numerical analysis method reported in this study was suggested as a complement of an actual fire test.

• Elastomers and Composites
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• v.40 no.3
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• pp.196-203
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• 2005

In this work, the engine oil resistant evaluation and breakdown analysis of room temperature vulcanizing silicone adhesives were performed through the surface properties, thermal stabilities, adhesive strength, and morphology measurements. As a result, the permeation of engine oil into adhesive specimens was carried out from surface to center in the specimens. And the oil content in the adhesive specimens was increased and the Si-O-Si bond of the adhesives was decomposed with increasing the aging time. The TGA results indicated that the thermal degradation was mainly occurred at under and surfaces of the specimens. The tensile strength, elongation, and adhesive strength of the adhesives were significantly decreased after the engine oil resistant tests, which could be attributed to the initial lose of adhesive properties resulting from the engine oil absorption and thermal aging. And the failure mode of the adhesive specimens was changed from cohesive failure to interfacial failure.

• Journal of Information Technology and Architecture
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• v.10 no.3
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• pp.371-378
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• 2013

Video-demand learning through E-learning continuously increases on these days. However, not all video-demand learning systems can be utilized properly. When students study by education videos not matched to level of their own, it is possible for them to lose interest in learning. It causes to reduce the learning efficiency. In order to solve the problem, we need to develop a recommendation system which recommends customized education videos according the study levels of students. In this paper, we estimate the study level based on the history of students' watching behaviors such as average watching time, skipping and rewinding of videos. In the experimental section, we demonstrate our recommendation system using real students' video watching history to show that our system is feasible in a practical environment.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.16-25
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• 2016

In severe loss of coolant accidents (LOCA), similar to those experienced at Fukushima Daiichi and Three Mile Island Unit 1, the zirconiumalloy fuel claddingmaterials are rapidlyheateddue to nuclear decay heating and rapid exothermic oxidation of zirconium with steam. This heating causes the cladding to rapidly react with steam, lose strength, burst or collapse, and generate large quantities of hydrogen gas. Although maintaining core cooling remains the highest priority in accident management, an accident tolerant fuel (ATF) design may extend coping and recovery time for operators to restore emergency power, and cooling, and achieve safe shutdown. An ATF is required to possess high resistance to steam oxidation to reduce hydrogen generation and sufficient mechanical strength to maintain fuel rod integrity and core coolability. The initiative undertaken by Electric Power Research Institute (EPRI) is to demonstrate the feasibility of developing an ATF cladding with capability to maintain its integrity in $1,200-1,500^{\circ}C$ steam for at least 24 hours. This ATF cladding utilizes thin-walled Mo-alloys coated with oxidation-resistant surface layers. The basic design consists of a thin-walled Mo alloy structural tube with a metallurgically bonded, oxidation-resistant outer layer. Two options are being investigated: a commercially available iron, chromium, and aluminum alloy with excellent high temperature oxidation resistance, and a Zr alloy with demonstratedcorrosionresistance.Asthese composite claddings will incorporate either no Zr, or thin Zr outer layers, hydrogen generation under severe LOCA conditions will be greatly reduced. Key technical challenges and uncertainties specific to Moalloy fuel cladding include: economic core design, industrial scale fabricability, radiation embrittlement, and corrosion and oxidation resistance during normal operation, transients, and severe accidents. Progress in each aspect has been made and key results are discussed in this document. In addition to assisting plants in meeting Light Water Reactor (LWR) challenges, accident-tolerant Mo-based cladding technologies are expected to be applicable for use in high-temperature helium and molten salt reactor designs, as well as nonnuclear high temperature applications.

• Molecules and Cells
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• v.40 no.1
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• pp.24-36
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• 2017

The stability of peptide-MHC complex (pMHC) is an important factor to shape the fate of peptide-specific T cell immune response, but how it influences on T cell activation process is poorly understood. To better understand that, we investigated various T cell activation events driven by $L^d$ MHCI loaded with graded concentrations of P2Ca and QL9 peptides, respectively, with 2C TCR Tg T cells; the binding strength of P2Ca for $L^d$ is measurably weaker than that of QL9, but either peptides in the context of $L^d$ interact with 2C TCR with a similar strength. When their concentrations required for early T cell activation events, which occur within several minutes to an hour, were concerned, $EC_{50}s$ of QL9 were about 100 folds lower than those of P2Ca, which was expected from their association constants for $L^d$. When $EC_{50}s$ for late activation events, which takes over several hours to occur, were concerned, the differences grew even larger (> 300 folds), suggesting that, due to weak binding, $L^d/P2Ca$ dissociate from each other more easily to lose its antigenicity in a short time. Accordingly, fixation of $L^d/P2Ca$ with paraformaldehyde resulted in a significant improvement in its immunogenicity. These results imply that binding strength of a peptide for a MHC is a critical factor to determine the duration of pMHC-mediated T cell activation and thus the attainment of productive T cell activation. It is also suggested that paraformaldehyde fixation should be an effective tool to ameliorate the immunogenicity of pMHC with a poor stability.

• Journal of the Korean Society of Food Culture
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• v.19 no.2
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• pp.223-238
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• 2004

In this paper, the differences between Korean and Japanese ways of seasonings are studied. The main results are summarized as follows: (1) Shouyu and Miso which are Japanese equivalents of soy sauce and bean paste of Korean foods are used in variety of different seasonings with some other ingredients while Korean counter parts are used only to add salty tastes. (2) Shouyu and Miso lose their flavors after considerable time of heating, while Korean soy sauce and bean pastes increase their tastes after heating. (3) Mirin adds sweety taste and glaze and Sake makes food soft or hard according to the moment of being added during cooking. (4) In Korean foods soy sauce, bean paste and red pepper paste are on the basis of tastes, Dashi is used in almost every Japanese food. (5) Seasoned vegetables of Korean food are prepared only with spices of green onion, garlic and sesame oil while seasoned fishes or vegetables are mixed with Shoyu or salt and vinegar in Japanese food. (6) In making Zorim, Korean traditional sauces are added from the beginning of heating. But in making Nimono, sugar, salt, vinegar, Shoyu and artificial taste are added in order during heating. (7) In grilling, main food for grilling in Korea is meat, which is prepared with a variety of spices such as soy sauce or/and red pepper pastes, garlic, green onion, sesame oil, sesame powder, pepper and sugar while mainly fishes are grilled with salt, occasionally with Shoyu or Miso in Japanese food. (8) Pan frying fishes are taken with soy sauce with vinegar in Korea but Tepura are eaten with Tentsuyu in Japan.

• Korean Journal of Health Education and Promotion
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• v.31 no.5
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• pp.147-158
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• 2014

Objectives: This study aims to examine the association of depression, suicidal behaviors with smartphone use behaviors among Korean adolescents. Methods: We analyzed data from 'Youth Health and Life Skills Survey' in 2013. The survey was based on self-reported questionnaires distributed to 915 grade 7th and 8th students at four middle schools in Gangdong-gu, Seoul, Korea in 2013 to evaluate the effects of 'Youth Health and Life Skills' program. Depression and suicidal behaviors were measured in terms of the experience rate, and smartphone use behaviors were measured with average hours of smartphone use a day and overindulged behaviors in smartphone use by using 5-point Likert scales. We examined the association of depression and suicidal behaviors with smartphone use behaviors by using t-test and regression analyses. Results: 21.5% of respondents have ever felt depressed or hopeless to lose interest in school life almost everyday for 2 weeks or longer in the past year. The experience rate of suicidal ideation, suicide plan, and suicidal attempt were 21.1%, 6.1%, and 5.7%, respectively. The mean of average hours of smartphone use a day was 3.9 hours, and the mean score of overindulged behaviors in smartphone use was 2.99. The students who have experienced depression and suicidal behaviors were more likely to have more smartphone using time and higher scores of overindulged behaviors in smartphne use than those who have not. Conclusion: We concluded that for preventing addictive or problematic smartphone use behaviors among adolescents we should consider and develop more positive strategies for the moderate use of smartphone than regulatory measures, which include the implementation of skill-based health education program including life skills at schools and the development of smartphone applications useful for resolving mental stress and promoting mental health.