• Journal of the Korean Geotechnical Society
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• v.20 no.5
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• pp.59-66
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• 2004

This study compared the reinforcing effect of sand by Geocell to those of newly devised Tirecell$^{\circledR}$ made by waste tires, tire mat by sidewalls of tires. Plate loading tests in a large chamber were conducted for different reinforcing materials at the same conditions of relative density, embedded depth of sand. The combination of Tirecell and sidewall gives the highest increase of bearing capacity and reduction of settlement. The Geocell with the same height of Tirecell gives similar reinforcement effect to the tire mat made by sidewalls.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.364-371
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• 2004

This study presented the reinforcing effect of sands by newly devised $Tirecell^{(R)}$ made by waste tires, tire mat by sidewalls of tires and Geocell. Plate loading tests were conducted for different reinforcing materials at the same condition. The combination of Tirecell and sidewall gives the highest increase of bearing capacity and reduction of settlement. The Geocell with the same hight of Tirecell gives similar reinforcement effect to the tire mat made by sidewalls.

• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1387-1395
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• 1994

Re-hydration properties of heated and ground CaO-SiO2-H2O system were studied under hydrothermal condition in order to examine the possibility of recycling ALC waste as raw materials of ALC. Powder of calcium silicate hydrates and ALC waste without heat treatment did not show further hydration while those of heat-treated at proper temperature showed re-hydration properties under hydrothermal condition. The lath-like shape of initially synthesized tobermorite was gradually turned into small debris during heating and plate-like tobermorite was crystallized during re-hydration of the heated powders. Heated and ground ALC waste could be added to natural raw mix for ALC at the ammount up to 20% with increased compressive strength and up to 30% with slightly decreased compressive strength. The optimum heating temperature of ALC for recycling was about 50$0^{\circ}C$.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.521-534
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• 2006

The Kimchi intake of elementary students in both school and home is decreasing due to their westernized eating habits which have been affected by the rapid economic growth and industrialization in our modem society. The purposes of this study were to examine the influence of menu selections on the Kimchi intake rate and to provide basic data for an appropriate Kimchi serving size to reduce the plate-waste rate. The results showed that the average daily intake rate of Kimchi of low-grade students was 58.2%, equating to 6${\sim}$18 g, compared to 64.6% for high-grade students, equivalent to 13${\sim}$24 g. Correlation analysis of the intake rate of menu items and Kimchi showed that the Kimchi intake rate increased with increasing total meal intake rate, rice intake rate, soup intake rate, rice mixed with grains intake rate, clear soup intake rate and soybean-paste soup intake rate, but that it decreased as the intake rate of seasoned uncooked vegetables of high-grade students increased. This study is expected to be utilized as a solution to increase the Kimchi intake rate of elementary school students, and also to determine the proper serving size per person on the menu items by grade.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.668-674
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• 2005

This study was carried out to investigate preference and perception of seafood among soldiers on cook's duty in military meal service. 58.9% of the respondents answered that they liked seafood and the major eating place were in their home(48.0%) and in the restaurant(40.4%). The favorite seafood cooking methods turned out to eat as raw fish, to grill, to stew, to fry in order. In comparison with the meat dishes, seafoods were considered superior to meat in nutritional value but evaluated inferior to meat in the aspects of sanitation and tasteless problem. 32.9% of the respondents answered they liked seafood dishes in military meal service and they disliked them because of taste or cooking method of the seafood. They liked fried or grilled seafood in military meal service. The plate waste amounts of the seafood menu were more than half in almost every surveyed menu and reasons for plate waste were fish smell and taste problems. The difficulties of cooking seafood in military meal service were breaking down of seafood during cooking and complexity of cooking. They scored seafood higher than average in nutrition, taste, diversity of cooking method and aspect of health. On the basis of the results above, introducing diverse cooking methods and menu are suggested and education of cooking skills and development of cooking facilities are needed in military meal service.

• Journal of the Korean Dietetic Association
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• v.12 no.4
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• pp.358-368
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• 2006

This study was conducted with 262 middle school student(118 boys, 144 girls) to examine their satisfaction, meal preference and improvement of school lunch program(SLP) in Jeonju area. Major plate waste ranked high in soup, fishes, vegetables, Kimch and rice. The overall reason for plate waste were listed as being tasteless and disliking food except for rice. In the case of rice, it because of too big portion size. On the satisfaction with SLP, the lowest satisfaction category was waiting time for meal. The changes after taking part in SLP of students ranked in having a regular meal time(31.4%), lessening to eat snack except for regular meals(18%) and correcting habit about picking favorite food(15.2%), in order. The improvement on SLP of students were listed as more appetite food, various side-dishes, squaring of the western and eastern food and so on. To improve the satisfaction SLP and provide a high quality service, it should be needed to make proper dining space, increase the frequency of survey on complaints and taste of students and reflect the menu plan.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.3
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• pp.279-287
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• 2021

For application in nuclear decommissioning, underwater laser cutting studies were conducted on thick stainless-steel plates for various cutting directions using a 6 kW fiber laser. For cutting along the horizontal direction with horizontal laser irradiation, the maximum cutting speed was 110 mm·min^-1 for a 48 mm thick stainless-steel plate. For cutting along the vertical direction with horizontal laser irradiation, a maximum speed of 120 mm·min^-1 was obtained for the same thickness, which confirmed that the cutting performance was similar but slightly better. Moreover, when cutting with vertically downward laser irradiation, the maximum cutting speed was 120 mm·min^-1 for a plate of the same thickness. Thus, the cutting performance for vertical irradiation was nearly identical to that for horizontal irradiation. In conclusion, it was possible to cut thick stainless-steel plates regardless of the laser irradiation and cutting directions, although the assist gas rose up due to buoyancy. These observations are expected to benefit laser cutting procedures during the actual dismantling of nuclear facilities.

• Journal of Environmental Science International
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• v.20 no.1
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• pp.137-146
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• 2011

In this research, food waste source reduction model for apartment was investigated. In spite of prohibition of direct landfill of food waste and continuous efforts made by government and local government, food waste production increases steadily. Recycling ratio of the food waste increases every year, but its products have many problems like low quality, stability, salt, odor etc. Household occupies 63.3% of whole food waste production and this is subject to be a key factor to control food waste. We surveyed S apartment in Kwangju city as a model case, in which administrative office and women's association adopted clean plate eating, separation of raw food waste and earth worm composting as a series of method for source reduction and recycling inside the apartment. With the help of residents' participation and practice, food waste production decreased 15.6% from 0.31 g/capita/day in 2007 to 0.26 g/capita/day in 2009 (domestic average 0.30 g/capita/day). Separation of raw food waste and its composting using earth worm were very effective, and were subject to resolve the problems of present food waste treatment technologies. And earth worm composting was very useful in environmental, economical, societal and educational aspects. Instead of economical incentive, educational programs about food value, environmental problem and critical method for food waste separation were more effective for promotion of source reduction. From the analyses on the process and success factors in this model, we could conclude that leader's role was one of the key factors for the settlement of source reduction, and that was to understand the seriousness of the food waste and to seek solution, to test techniques, and to practice by oneself. Furthermore, networking and collaboration among residents, local government, NGO and local press promoted residents' participation, and it was through various education and investigation. Finally, source reduction and self recycling model of food waste in the apartment, that applies separating raw food waste and earth worm composting based on the collaboration among residents, local government, NGO, and local press, should be disseminated, and environmental policy also should be changed to make it possible.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.342-348
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• 2001

This study was conducted to obtain granular crystalline gypsum that can be used as raw material for plaster boards or cements from waste Plaster board. We could disintegrate preferentially gypsum to gypsum needle in 10${\mu}{\textrm}{m}$ or less size among the contents of waste plaster board (gypsum, paper, fiber, and inorganic material .etc.) by hydration afterwards the dehydration of crushed waste plaster board. In this case, the optimum conditions for minimizing the size of gypsum were dehydration rate of 75%~ 85%, hydration concentration of 10~20%, agitation speed of 250~400rpm, crushing size of 2cm or less. Gypsum of 98.21% grade was recovered with 99.0% yield from under screenings of 325mesh wet screening which followed by the dehydration-hydration process performed in the conditions of dehydration rate of 80%, hydration concentration of 15%, agitation speed of 300rpm, crushing size of 2cm or less. Subsequently, Plate-like Crystalline gypsum of is 151${\mu}{\textrm}{m}$ size and the grade of 99.49% with the Yield of 98.0% from the upper screenings of 270mesh wet screening carried out after the re-crystallization of the recovered gypsum needle slurry.

• Resources Recycling
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• v.10 no.6
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• pp.43-52
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• 2001

This study was conducted to obtain granular crystalline gypsum that can be used as raw material for Plaster boards or cements from waste Plaster board. Gypsum could be Preferentially disintegrated to gypsum needle in $10\mu\textrm{m}$ or less size by hydration after the dehydration of crushed waste Plaster board. The finer the gypsum needle, it is easier to remove coarse impurities and to recover the gypsum needle. The optimum conditions for obtain the finer gypsum size were dehydration rate of 75~85%, solid concentration at hydration of 10~15%, agitation speed of 250~400 rpm, crushing size before dehydration of 2 cm or less. Gypsum of 98.21% grade was recovered with 99.0% yield as the undersize of 325 mesh wet screening followed by the dehydration-hydration process performed at the conditions of dehydration rate of 80%, solid concentration at hydration of 15%, agitation speed of 300 rpm, crushing size before dehydration of 2 cm or less. After the recrystallization of recovered gypsum, Plate-like gypsum of $151\mu\textrm{m}$ size with 99.49% grade was obtained as the oversize of 270 mesh in a wet screening.