• Nuclear Engineering and Technology
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• v.42 no.2
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• pp.175-182
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• 2010

As part of a fundamental study on the volume reduction of contaminated concrete wastes, the separation characteristics of the aggregates and the distribution of the radioactivity in the aggregates were investigated. Radioisotope $^{60}Co$ was artificially used as a model contaminant for non-radioactive crushed concrete waste. Volume reduction for radioactively contaminated dismantled concrete wastes was carried out using activated heavy weight concrete taken from the Korea Research Reactor 2 (KRR-2) and light weight concrete from the Uranium Conversion Plant (UCP). The results showed that most of the $^{60}Co$ nuclide was easily separated from the contaminated dismantled concrete waste and was concentrated mainly in the porous fine cement paste. The heating temperature was found to be one of the effective parameters in the removal of the radionuclide from concrete waste. The volume reduction rate achieved was above 80% for the KRR-2 concrete wastes and above 75% for the UCP concrete wastes by thermal and mechanical treatment.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.1
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• pp.89-97
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• 2000

The goal of this study was to fine the way of reduction on food waste in the university cafeteria. A survey was conducted on the 500 faculty members using Yeungnam University cafeteria , and if illustrate the faculty's use and perception for the reduction of food waste. Its results can be summarized as follows ; 32.0 % of the total users use the university cafeteria everyday, also 56.6% of the users preferred Korean style dish. Female users left more food than the male users resulting in more food wastes. The male users resulting in more food waste and the most leaving food was Kimchi than the other types of foods. The most favorite stew and side dish turned out to be Yukgaejang and Bulgogi respectively, also Kimchibokkumbab was the preffered dish. But they disliked Sunjiguk , Ginger, Jellyfish and Mackerel pike. The preception of male users on the reduction of food waste was lower than that of female users. The best way of food waste treatment recognized by the users were utilizing the waste food as fodder for animals or fertilizer.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.95-98
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• 2003

Waste lime is produced as by-products in chemical industry, Reuse of waste lime mixed with soil for banking and backfill material in civil works was analysed in this study. For this purpose, environmental effect of waste lime admixtures was tested. Thus, this study presents the leaching characterization of waste lime in laboratory batch and column tests. Countermeasure for reduction of environmental effects was suggested from the test results.

• Journal of the Korean Dietetic Association
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• v.18 no.2
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• pp.126-140
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• 2012

The purpose of this study was to investigate elementary school students' perception of food waste as well as to identify factors affecting the plate waste rate of school foodservice in the Gyeongnam area. Questionnaires were distributed to 280 students from June 20 to July 5, 2011 and a total of 279 were analyzed. The results of this study were as follows. First, the main reason of plate waste was 'big portion size', which suggests that portion size should be adjusted. Second, the attitude for food waste reduction was 3.67 based on a 5-point Likert scale (1: strongly disagree, 5: strongly agree). Third, the average plate waste rate of school foodservice was 18.65%. Fourth, there were four factors affecting plate waste rate; balanced/unbalanced diet, satisfaction of school foodservice, need for nutrition education related to food waste, and attitude towards food waste reduction. The plate waste rates of the students who ate a balanced diet were significantly lower than those of the students who ate an unbalanced diet (P<0.001). The plate waste rates of the students who were satisfied with school foodservice were significantly lower than those of the students who were unsatisfied (P<0.001). The plate waste rates of the students who recognized the need for nutrition education were significantly lower that those of the students who did not recognize this (P<0.01). Finally, the students' attitudes towards food waste reduction were significantly negatively correlated with plate waste rate (P<0.01). In conclusion, in order to successfully reduce plate waste in school foodservice, nutrition education should be provided on proper portion size, balanced diet, and food waste. Further, introduction of partial self-service by school foodservice should be reviewed, and strategies for the improvement of school foodservice satisfaction should be applied.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.756-763
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• 2015

As food waste problems become more severe, the need for reduction plans is increasing. Thus, this study aimed to discover the attitudes towards and the intentions to reduce restaurant food waste as well as the importance of and intentions to participate in reduction plans among adults customers A self-administrated questionnaire was given to 361 adults (216 men and 145 women) over 20 years old residing in Seoul and Gyeonggi province. According to the results, the respondents regarded restaurant food waste problems as serious (4.01). The biggest reason for leaving food was concern about hygiene (3.57), followed by tasting food (3.34) and portions that were too large (3.10). 57.6% responded that they try to reduce food waste when dining out. Women over 30 admitted to leaving food when dining out if the food did not taste as expected, if they had health concerns about additives such as condiments, and for body weight management. The overall average degree of awareness on the gravity of restaurant food waste problems was 4.06, indicating that respondents deeply empathized with the matter. Women showed higher alertness compared to men, and respondents in their 30s or over did more than those in their 20s. Also, respondents who try to reduce food waste when dining out had higher levels of concern than those who did not. According to the results from measuring the importance of and intention to participate in restaurant food waste reduction plans, taking away left-over food was the best option. In short, citizenship improvement campaigns should be designed for restaurants and related organizations in order to stimulate the need and effects of efforts to reduce dine-out food waste and induce aggressive participation by consumers. Diverse methods to increase actual consumer participation in food waste reduction plans that show high consumer participation intentions also needs to be developed.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.61-70
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• 2005

In order to reduce salt(as NaCl) contents in food waste and to improve the quality of discharged wastewater produced during the recycling process of food waste for the purpose of compost and feed stuff, a salt reduction process by added water into food waste was developed. The pilot plant with a rotary type salt reduction equipment to manage continuously 0.5 ton food waste per hour was constructed and the efficiency was tested. The amount of added water was calculated by the water content and the efficiency of dewatering process of food waste. Approximately 0.8 liter water per a kilogram of food waste was injected into the reactor in which food waste was pouring simultaneously, then diluted/mixed in a rotary reactor. About 1.1 liter of leachate including added water was generated, but the leachate contained a very high content of organic particles, so most particles were recovered by two step solid-liquid separation process. The first step was a gravitational filtering process using screens with a pore diameter of 1mm, and the second separation process was centrifugal process. Organic quality of food waste which had been desalted was maintained by inputting the entirely recovered organic particles. The efficiency of salt reduction of food waste was estimated by measuring a chloride anion by titration and salinity by a probe. The results by the two different measuring methods were always over 50%, and the quality of final wastewater was improved up to $200mg/{\ell}$ as TS(total solid) by an additional settling process after the two step solid-liquid separation process.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.2
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• pp.181-189
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• 2017

The purpose of this paper is to evaluate several leading options for the management of radioactive metallic waste against a set of general criteria including safety, cost effectiveness, radiological dose to workers and volume reduction. Several options for managing metallic waste generated from decommissioning are evaluated in this paper. These options include free release, controlled reuse, and direct disposal of radioactive metallic waste. Each of these options may involve treatment of the metal waste for volume reduction by physical cutting or melting. A multi-criteria decision analysis was performed using the Analytic Hierarchy Process (AHP) to rank the options. Melting radioactive metallic waste to produce metal ingots with controlled reuse or free release is found to be the most effective option.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.49-54
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• 2001

Using waste glass in concrete can cause crack and strength loss by the expansion of alkali-silica reaction(ASR). In this study, ASR expansion and properties of strength were analyzed in terms of brown waste glass content, and fibers(steel fiber, polypropylene fiber) and fiber content for reduction ASR expansion due to waste glass. In this accelerated ASTM C 1260 test of waste glass, pessimum content can not be found. Also, when used the fibers with waste g1ass, there is an effect on reduction of expansion and strength loss due to ASR between the alkali in the cement paste and the silica in the waste glass. Specially, adding 1.5 vol.% of steel fiber to 20% of waste glass the expansion ratio was reduced by 40% and flexural strength was developed by up to 110% comparing with only Waste glass ( $80^{\circ}C$ $H_{2}$ O curing).

• Environmental Engineering Research
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• v.10 no.1
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• pp.1-6
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• 2005

Hexavalent chromium in aqueous solutions was successfully removed via sorption and reduction in the presence of waste leaves. Cr(VI) removal followed a first-order reaction, and removal rates were proportional to the amount of waste leaves used in the tests. Most of Cr(VI) were removed via sorption in early stages of the tests, but the reduction reaction played a significant role in Cr(VI) removal later. Solution pHs were continuously decreased due to the microbial activity, which was induced from the microorganisms attached on waste leaves. The decreased solution pHs further enhanced the sorption and reduction of Cr(VI). To characterize the microorganisms found in the tests, a denaturing gradient gel electrophoresis (DGGE) method was used. The majority of microorganisms were composed of Bacillus sp. which can reduce Cr(VI). Thus, waste leaves can be effective reactive media for the treatment of Cr(VI) in the subsurface.

• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.840-846
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• 2016

Great amounts of solid radioactive waste (second waste) and waste solution are generated from the remediation of uranium-contaminated soil. To reduce these, we investigated washing with a less acidic solution and recycling the waste solution after removal of the dominant elements and uranium. Increasing the pH of the washing solution from 0.5 to 1.5 would be beneficial in terms of economics. A high content of calcium in the waste solution was precipitated by adding sulfuric acid. The second waste can be significantly reduced by using sorption and desorption techniques on ampholyte resin S-950 prior to the precipitation of uranium at pH 3.0.