• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.455-461
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• 2006

High temperature dielectric constants of the various ceramic materials have been measured using cavity perturbation method. The measurements were applied to refractory, traditional and fine ceramic powder compacts from room temperature to $1200^{\circ}C$. Calibration constant in the equation suggested by Hutcheon et al., was determined from the dielectric constants of reference specimen (teflon and alumina) at room temperature. From these results, informations on the refectory materials were obtained for the microwave kiln design and understanding of the microwave heating effects of ceramics have been improved.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.133-140
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• 1998

The food wastes from a refectory and an eating house were heated in domestic microwave oven(700W) equipped with a fan and the drying rates and destruction of microorganisms were investigated. The drying rate was decreased with the size of food waste and the food wastes in polypropylene basket were dried faster than that on glass dish. The rate was increased with lower initial moisture content. Death rate of microorganisms was also decreased with the size of food waste. Ninety eight percent of reduction in viable cell numbers for the 400g of food waste could be achieved in 240sec of microwave irradiation. The growth of microorganisms in food wastes after microwave irradiated was observed at $32^{\circ}C$ and 95% relative humidity after 7days and the cell numbers in microwave irradiated food wastes were found to be 1/2 ~ 1/20 of the numbers in untreated wastes in accordance with the mass and the length of exposed time to microwave. To minimize the moisture and microorganisms in food wastes, the use of microwave oven are recommended.

• Journal of Engineering Education Research
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• v.21 no.3
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• pp.31-37
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• 2018

The purpose of this study is to develop a method to improve the quality of engineering education by using Kano's dualistic quality model and Timko's customer satisfaction coefficient. The results of the study are as follows. Firstly, the top priority for major education is improve 'smooth support of class medium' as an attractive and one-dimensional quality element, and 'use of various examples' and 'specialty improvement of major curriculum' as an one-dimensional quality element. Secondly, the top priority for general education is improve 'liberal education curriculum' as an attractive quality element 'use of various examples' as an one-dimensional quality element. Thirdly, the top priority for extra-curriculum is develop and provide 'study support program of student' and 'voluntary service'. Fourthly, the top priority for administrative service and facilities is improve 'increase of scholarship' and expand 'service of welfare facilities as dormitory and refectory' as an one-dimensional quality element.

• Korean Journal of Community Nutrition
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• v.4 no.3
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• pp.366-374
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• 1999

The purpose of this study was to investigate the change in food habits of girl students 1985 and 1998. A similar study had been conducted in 1985 and this study was carried in May, 1998 using the questionnaires. The subjects were 746 female students in middle school, high school and university students living in Jeonbuk region. The average score of food habit was $4.11{\pm}1.63$ out of a possible 10. This averge is lower than the 4.91 score in 1985, especially the score of university students lowered from 4.80 points to $3.52{\pm}1.58$ points. The correlation coefficient between the score of food habit and standard of living, utilizing increase as compared with the 54.9% in 1985. The most preferred side-dish changed from fried food to Kimchi. The preference of snacks was not changed. Eating bread increased at breakfast but eating noodles increased at lunch. University students' lunch basket preparation ratio decreased from 32.6% to 3.3%, so they had more noodles at refectory than lunch basket. The reason for skipping breakfast did not changes, but skipping lunch changed from annoyance due to lunch basket preparation to lack of time and no appetite. Skipping supper was changed from missing time to weight control. Having supper at home decreased from 96.6% to 75.9%. Substitution food on no preparation of lunch basket was changed from bread to noodles. The preference for biscuits and snack did not changes but fewer students preftered bread and fried food. In order to improve the nutritional status of the girl students, they must establish good food habits, especially by eating 3 regular meals per day and balancing their diet they should also be notified that severe weight control is very harmful for health.

• Structural Engineering and Mechanics
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• v.72 no.3
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• pp.339-354
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• 2019

Reusing building materials and concrete of old buildings can be a promising strategy for sustained development. In buildings, the performance of materials under elevated temperatures is of particular interest for determining fire resistance. In this study, the effect of pozzolan and aggregate type on properties of concrete exposed to fire was investigated. In doing so, nanosilica with cement-replacement levels of 0, 2, and 4% as well as silica fume and ultrafine fly ash with cement-replacement levels of 0, 7.5, and 15% were used to study effect of pozzolan type, and recycled refractory brick (RRB) fine aggregate replacing natural fine aggregate by 0 and 100% was utilized to explore effect of aggregate type. A total of 126 cubic concrete specimens were manufactured and then investigated in terms of compressive strength, ultrasonic pulse velocity, and weight loss at $23^{\circ}C$ and immediately after exposure to 400 and $800^{\circ}C$. Results show that replacing 100% of natural fine aggregate with recycled refectory brick fine aggregate in the concretes exposed to heat was desirable, in that it led to a mean compressive strength increase of above 25% at $800^{\circ}C$. In general, among the pozzolans used here, silica fume demonstrated the best performance in terms of retaining the compressive strength of heated concretes. The higher replacement level of silica fume and ultrafine fly ash pozzolans in the mixes containing RRB fine aggregate led to a greater weight loss rate, while the higher replacement level of nanosilica reduced the weight loss rate.

• Journal of the Korean Dietetic Association
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• v.5 no.1
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• pp.85-98
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• 1999

The purpose of this study was to find the proper methods of school food service conducted from June 20th July 30th in 1996. The subjects of this study were 587 parents of students, 794 students and 359 school teachers at 508 middle and high schools in Seoul and Kyunggi area. And the result was as follow. A total of 48.3% of respondent answered they had breakfast regularly. The reasons why they had breakfast, were habits(34.4%) followed by hunger(28.2%), health(19.9%), parent's persuasion(17.5%). They reasons why they didn't have breakfast are, lacks of time(68.8%) followed by absence of appetite(20.5%), diet(4.5%). About the question the problem of eating habits the most of parents of students, chose an unbalanced diet(25.9%), followed by overeating of snacks(21.7%), voracious eating(18.0%), not eating meals(17.5%), eating little(10%) and overeating(6.8%). At the research of an unbalanced diet, the 63.3% of respondents said they eat evenly while the 36.7% said they had an unbalanced diet. From the research of correlativity between food service at elementary schools and eating habits, we knew that the experience of school food service had an effect on an unbalanced diet. And the students living in Seoul complained more than in Kyunggi. The question about the quality of food, 69.0% of respondents said they were not so bad. While 21.2% said not delicious at all just 9.8% of students said they were very satisfied with the taste. Interestingly, more middle school students both in Kyunggi and Seoul answered the food was delicious than high school students. About the question of the price, 49.5% of students thought appropriate(49.5%) while 44.3% said it was too high. Just 5.9% students answered cheap(5.9%). And students living in Kyunggi thought the price was high than students in Seoul. 62.9% of respondents think their refectories were clean while 22.8% think not clean. And 14.3% answered said dirty. Snack bars at school were managed by the contract with trusters(63.2%), while by the school itself(32.6%).

• Journal of the Korean Society of Food Culture
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• v.13 no.3
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• pp.169-182
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• 1998

This study was conducted to investigate the consumers' Dining-out preference and behavior for the chilled meat consumption strategy . A total of 328 persons in Seoul, Kyunggi areas were selected by stratified random sampling method and were responded to this study questionnaire which was composed of six parts with 65 statements about chilled meat consumption. 1. The frequency of Dining-out is characterized that 'once a month' is the highest pattern of consumers(46.3%) : In that cases, the married people showed 'once a month'(52.7%) and 'once biweekly'(23.3%), but the unmarried people showed the more frequent pattern as 'once a week'(27.3%) and 'twice a week'(27.3%). And the frequency of Dining-out in relation with the education level revealed that 'the graduate people' are the highest (37.5%). 2. Generally the first food for the Dining-out is 'Kalbi'(26.2%), and the others were 'pork grilling','chilled meat grilling','fish sasimi','chinese foods','pizza' etc.... But there were some variation in relation with incomes and housing types: For the agriculture/physical labor class, they prefers the 'pork griling'(25.0%), the office work class prefers the 'Kalbi' For the house-owner group, they prefers the 'Kalbi', but the house-renting/lodging group, they prefer the 'chinese food' or 'pork grilling' etc.... 3. In choosing the Dining-out place,'quality of food'(54.3%) and 'hygiene'(21.0%) were rated as the first important factor. 4.'Soups', 'Noodles' and 'Cooked rice in casserole' were chosen as good lunch menu : for male, they prefer the 'Soups', but females prefer 'Cooked rice in casserole'. 5. People with commercials/services(44.7%) and agriculture/physical labor(50.0%) ate their lunch in private restaurant, but peoples in the office work(57.0%)/public service personnel(70.4%) and industry use refectory; and it showed significant difference. 6. Consumers prefer the chilled meat as a Dining-out menu, but they didn't recognize the difference between chilled meat and frozen meat 7. For Dining-out menu, many people proper the beef, but the price of beef was so high than pork, agriculture/physical labor class choose the pork grilling instead of beef : commercials/services/office worker prefer the beef chilled meat . 8. The first admirable cooking method for chilled meat is direct radiation grilling with charcoal and many of consumers prefer tender, marbling, some chewy and juicy, flavor, soft as a quality of meat but physical labor class prefer the some tough and chewy texture.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.160-167
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• 2000

This study was performed to evaluate efficiency of soil microbial inoculator for active composting of food waste. In addition the number of microorganisms in roil microbial inoculator and the effect of seeding in the process of composting were investigated. food waste samples collected from a refectory were analyzed for physical-chemical properties. The samples were adjusted to moisture content of 65% by saw dust and seeded with soil microbial inoculator of 10% by the weight in case of reactor B. The number of microorganisms, aerobic bacteria, actinomyces, yeast, and fungi in soil microbial inoculator were over $2.98{\times}10^9/g$, $3.93{\times}10^7/g$, $1.21{\times} 10^5/g$, and $5.79{\times}10^7/g$, respectively. During the process of composting, the highest temperatures were $63.4^{\circ}C$ at reactor A(unseeded control)after 10 days and $66.8^{\circ}C$ at reactor B(seeded compost) after 4 days. The pH values of reactor A and B rapidly increased after 3 days and after first few days during composting period, respectively. The highest $CO_2$ concentrations were 6.1%(after 10 days) and 10.8%(afer 4 days) in reactor A and B, respectively. The degradation rates of organic matter(rd) between reactor A and B increased by 17.1% and 64.5%, respectively Consequently, the effects of Inoculation on comporting parameter such as temperature increasing, pH change, chemical properties, and the degradation rates of organic matter(rd) were higher in seeded compost than in unseeded control.

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.183-188
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• 1984

This paper was concerned with the investigation on the species of fungi detected in indoor environments. Mycological survey on the wall of buildings and houses in Seoul was performed from December 26, 1983 to February 11, 1984. The collected fungi with the sterilized cotton rod were caltivated and isolated in the Potato-Detrose Agar medium with chloramphenicol. The fungi detected in hospital were Cladosporium sp., Penicillium sp., Alternaria sp., Chaetomium sp. and others. The fungi detected in household were Penicillium sp., Alternaria sp., Aspergillus sp., Cladosporium sp., Rhizopus sp., Trichoderma sp. and others. The kitchen of household was more contaminated by fungi than the living room and others. In hospital, it was much contaminated by the same species of the aboves on the wall of lobby and refectory. As the above results were recognized, the higher humidity and the more poor ventilation, the more species and amount of fungi were contaminated. Further studies on the identification of pathogenic fungi should be continued. The proper regulation for the hygienic maintenance of indoor environment in household, hospital and other public buildings should be recommended as well.