• Analytical Science and Technology
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• v.15 no.1
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• pp.80-86
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• 2002

The simultaneous analysis of the odorous compounds designated by law in Korea and Japan was examined with the thermal desorber gas chromatography-mass spectrometry using one column. The approximate concentrations of trimethyl amine, acetaldehyde, methyl mercaptan and dimethyl sulfide were estimated. Styrene, dimethyl disulfide, propionaldehyde, n-butyl aldehyde, i-butyl aldehyde, n-valeraldehyde, i-valeraldehyde, ethyl acetate, toluene, xylene, methyl i-butyl ketone and i-butanol were detected at concentrations of the detection limits of their threshold values. As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds emitted from compost procedure of food waste were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated from the concentrations and threshold values of the detected components. From the result of analysis, 34 compounds were confirmed and among them, trimethyl amine, i-valeraldehyde, methyl mercaptan, methyl allyl sulfide, dimethyl sulfide, acetaldehyde, ethanol, n-butyaldehyde were expected to attribute to the odor in order of strength.

• Food Engineering Progress
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• v.15 no.1
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• pp.22-27
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• 2011

Changes in total nitrogen (T.N.) and total phosphate (T.P.) content in environmental waste water upon the reaction of biological purifying reagents were measured and the reaction rate was evaluated. The purification capacity of two biological purifying reagents composed of vegetable Lactobacillus fermentum (V.L.F.), Saccharomyces cerevisiae(S.C), and Bacillus subtilis(B.S.) were evaluated and compared with that of commercial water purification system operating by local government. After 18days of reaction, the mixture of V.L.F. and S.C. showed dramatic decrease of T.N.(36.21% of the initial value). The mixture of V.L.F., S.C., and B.S. showed faster reaction rate to decrease T.P. compared with that of the mixture of V.L.F. and S.C. The reaction constant of mixture of V.L.F. and S.C. was estimated to be 0.178 $day^{-1}$ by the curve fitting of the data of changes in T.N. during the reaction.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.21-33
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• 2007

The purpose of this study was to evaluate the consciousness and behavior for environmental problems of university student and the necessity of schooling for environmental education. In order to achieve this purpose, a method of questionnaire was administered to total 1012 students selected from 5 universities in Suwon Si etc.. The results in questionnaire were as follows. Most students responded that living environmental education in middle and high school was helpful(70.4%) in practical living. And the most serious problem of living environmental pollution was water pollution(53.6%), air pollution(19.8%), waste material pollution(15.8%), food additives(7.9%), genetic modified organism(3.0%), respectively. And students obtained most knowledge of living environmental problems in internet(87.0%). Also most students responded that the main source and cause of water pollution and air pollution was industrial waste 63.4%, vehicles 61.5%, respectively. And level of environmental behaviors and consciousness of students distributed by major was science & engineering 2.13/4, etc. 2.08/4, art & athletics 1.6/4, liberal art 1.53/4, respectively. And also most respondents have recognition the necessity of schooling for environmental education.

• Journal of Korean society of Dental Hygiene
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• v.12 no.6
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• pp.1193-1202
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• 2012

Objectives : The purpose of our study was to examine the relationship of oral health status such as dental caries and the performance of dietary action guides with six items. Methods : Oral examination and self-administrated questionnaire were conducted on 87 disabled students, aged 6-19 who were attending special school in the area of the metropolitan Seoul. Two logistic regression models to estimate odds ratios and 95% confidence intervals were used to investigate the association dental caries experience and the performance of dietary action guides after controlling for potential confounders. Results : The proportion of study subjects with caries were 37.9%, 26.9%(male) and 54.3%(female), respectively(p<0.05). There was significantly difference the subjects with caries and perceived oral health status(p<0.01). Among the dietary action guides items, skipping breakfast and not avoiding waste food were significantly higher in the proportion of subjects' caries(p<0.05, p<0.01, respectively). The avoiding waste food groups had more possibility of having caries significantly(p<0.05), even after controlling gender, and perceived oral health status. Conclusions : These results indicate that oral health promotion policy with dietary action guides should be strengthened for support of disabled student's dental health.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.125-134
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• 2001

The purpose of this study is to provide basic information for a future countermeasure municipal and to establish several wastes policy after investigating solid wastes from Sunchon City. In addition, this research can be supported to manage of recycling plant and to reuse plant of each wastes. Results are as bellows after checking up and analysis type of waste in Sunchon city Unit solid waste generation rate from single family is $0.50kg/person{\cdot}day$, and total solid wastes are 41.9ton/day. Unit solid waste generation rate from apartments is $0.45kg/person{\cdot}day$, and solid wastes generation is 55.5ton/day. Unit solid waste generation rate from agricultural is $0.22kg/person{\cdot}day$ and total solid wastes are 13.5ton/day. That show total amount of municipal solid wastes from residential are 110.9ton/day. Unit solid waste generation rate from traditional markets is $1.85kg/person{\cdot}day$, and solid waste total volume is 5,400kg/day. Unit solid waste generation rate from small store is $2.03kg/person{\cdot}day$, and solid waste total are 25,101kg/day. Therefore, this show that total wastes are 30.50kg from downtown and commercial area. Solid waste quantity from Industrial area (Factory region) is 8.5ton and in case of school and hospitals are 7.2kg/day and 3.0kg/day. Solid waste amount from Institutional is 6.6kg/day. Food wastes were eliminated from municipal solid wastes as standard 63.4ton/day, and combustible wastes were 126.9ton/day. If it schedule about 5 years (by 2006) as durable year for food wastes treatment plant, it is expected 42.5ton/day for treatment capacity. We can judge that it is effective to be set 2 lines equipment ${\times}25ton/day$ as treatment ability under considering unexpected working condition such as any repair, trouble and an electrical load. If it schedule about 10 years (by 2011) as durable year for food wastes treatment plant, it is expected 150 ton/day for treatment capacity. We can conclude that it is effective to be set 2 lines equipment ${\times}80ton/day$ as treatment ability under considering working condition such as low loaded operating and the repair for incineration.

• KSBB Journal
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• v.20 no.6
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• pp.438-442
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• 2005

Batch experiments were performed to investigate the effects of volumetric mixing ratio(v/v) of two substrates, food wastes(FW) and waste activated sludge(WAS). In batch experiments, optimum mixing ratio for hydrogen production was found at $10{\sim}20$ v/v % addition of WAS. CSTR(Continuous Stirred tank reactor) was operated to investigate the hydrogen productivity and the microbial community under various HRTs and volumetric mixing ratio(v/v) of two substrates. The maximum yield of specific hydrogen production, 140 mL/g VSS, was found at HRT of 2 day and the volumetric mixing ratio of 20:80(WAS:FW). The spatial distribution of hydrogen producing bacteria was observed in anaerobic fermentative reactor using fluorescent in situ hybridization(FISH) method.

• Nutrition Research and Practice
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• v.4 no.5
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• pp.400-404
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• 2010

School lunches serve to improve nutritional status and to promote the health of children. The purpose of this study was to investigate the portion sizes of school lunches served and consumed in Japanese elementary schools. In addition, gender difference in servings and consumption were also studied. A cross-sectional study was undertaken between October 2007 and February 2008 in schools located in Tokyo and Okayama, Japan. A total of 192 fifth-grade children attending four elementary schools participated in this study. Weighed plate waste methods and observation were used to collect dietary data for two non-consecutive days. The proportion of children who chose staple foods along with main dishes and/or side dishes for at least one day was higher in boys than in girls (respectively, for staple food: 42.1% vs. 9.3%, for main dish and/or side dish: 68.4% vs. 44.3%, P < 0.001). The ratio of initial amount served to amount offered was $0.88{\pm}0.11$ for boys and $0.84{\pm}0.10$ for girls (P < 0.05). The ratio of amount consumed to amount offered was $1.04{\pm}0.19$ for boys and $0.88{\pm}0.12$ for girls (P < 0.001). Weight was related to amount consumed both in boys (r = 0.222, P < 0.05) and in girls (r = 0.201, P < 0.05). These findings suggest that the nutritional standards of school lunch programs should take into account gender differences. Clearly, boys were more likely to consume more than the initial amounts served due to their higher propensity to take second helpings. Boys feel few reservations about taking second helpings to adjust their total intake. However, school lunch plans should take into consideration girls' reluctance to do so, by serving appropriate initial portion sizes.

• Microbiology and Biotechnology Letters
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• v.51 no.3
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• pp.257-267
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• 2023

The potential polyhydroxyalkanoates (PHA)-producing bacteria, Bacillus megaterium PP-10, was successfully isolated and studied its feasibility for utilization of pineapple peel waste (PPW) as a cheap carbon substrate. The PPW was pretreated with 1% (v/v) H₂SO₄ under steam sterilization and about 26.4 g/l of total reducing sugar (TRS) in pineapple peel hydrolysate (PPH) was generated and main fermentable sugars were glucose and fructose. A maximum cell growth and PHA concentration of 3.63 ± 0.07 g/l and 1.98 ± 0.09 g/l (about 54.58 ± 2.39%DCW) were received in only 12 h when grown in PPH. Interestingly, PHA productivity and biomass yield (Y_x/s) in PPH was about 4 times and 1.5 times higher than in glucose. To achieve the highest DCW and PHA production, the optimal culture conditions e.g. carbon to nitrogen ratios of 40 mole/mole, incubation temperature at 35℃ and shaking speed of 200 rpm were performed and a maximum DCW up to 4.24 ± 0.04 g/l and PHA concentration of 2.68 ± 0.02 g/l (61% DCW) were obtained. The produced PHA was further examined its monomer composition and found to contain only 3-hydroxybutyrate (3HB). This finding corresponded with the presence of class IV PHA synthase gene. Finally, certain thermal properties of the produced PHA i.e. the melting temperature (T_m) and the glass transition temperature (T_g) were about 176℃ and -4℃, respectively whereas the M_w was about 1.07 KDa ; therefore, the newly isolated B. megaterium PP-10 is a promising bacterial candidate for the efficient conversion of low-cost PPH to PHA.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.115-120
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• 2019

This study is aimed at giving directions for the development of fresh food delivery packaging design in the domestic e-commerce market. First literature study of food consumption trend, cold chain system and zero waste campaign related to e-commerce food market. Second, packaging designs of e-commerce fresh food in domestic and foreign were analyzed and also the prospective studies were checked to find out the future direction of packaging designs. Studies show that the packaging design of delivery for fresh food should not only be kept freshness, also consider the usefulness, convenience and environmental protection from various angles.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.28-32
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• 2011

This paper introduces about the study on the construction of zero energy villages in Korea using waste and biomass, and explains how to analyze the quantity of various resources from agriculture, livestock industry, forestry, and food waste with a village as a unit. Finally, three different scenarios for the construction of zero energy villages were suggested, based on the presumed amount of energy per each town.