• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.419-424
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• 2007

According to increase of consumer's desire for clean tap water, advanced treatment processes include with membrane, ozone, and granular activated carbon(GAC) were introduced. In order to evaluate the effect of advanced treatment processes for residual chlorine decay and trihalomethane(THM) formation in water distribution system, dissolved organic matter(DOC) removal of each advanced treatment process was investigated. The residual chlorine decay and THM formation using bottle tests were also evaluated. $UV_{254}$ removal in all advanced treatment was better than DOC removal. Especially, DOC by ozone treated was removed as 4% in contrast with sand filtered water, but $UV_{254}$ was removed about 17%. This result might be due to convert from hydrophobic DOC to hydrophilic DOC by ozonation. Ozone/GAC process was most effective process for DOC removal. The residual chlorine decay constants in treated water by sand filtration, ozonation, GAC adsorption, and ozone/GAC processes were 0.0230, 0.0307, 0.0117 and 0.0098 $hr^{-1}$, respectively. The sand filtered water was produced 81.8 ${\mu}g/L$ of THM after 190 hours of reaction time, as the treated water by ozone, GAC, and Ozone/GAC was less produced 6.0, 26.2, 30.3% in contrast with sand filtered water, respectively. Consequently, the durability of residual chlorine and reduction of THM formation were improved by advanced treatment processes.

• Analytical Science and Technology
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• v.13 no.2
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• pp.258-267
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• 2000

The result of five year's experience on Inter-laboratory Comparison for Analyses of Heavy Metals and Organic Solvent Metabolites in Biological Samples was described. Since 1995, around a hundred laboratories in the Occupational Health have participated this program twice per year by the Industrial Safety and Health Law. Four metals in blood and five organic solvent metabolites in urine were examined. Reference samples were made by spiking standard materials to human blood or urine pools treated previously to give homogeneity and stability for a specific time periods. Some reference samples for organic solvent metabolites were made from workers' urine who were exposed to the organic solvents. Some items such as Lead in blood and Hippuric acid in urine showed good accordance between participants while the other items such as Mercury and N-methylformamide in urine showed poor proficient rate. The results were published in the internet or newspaper to help the consumer of the laboratory's service to get the information on them and to make competition between them. The inter-laboratory's comparison program have done greate role to improve the ability of analysis and reliability of analytical data produced from each laboratory.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.74-85
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• 2003

The purpose of this study is to investigate present situation of recovery and treatment of waste home appliances, and to supply basic data for active reuse and recycling of waste home appliances. Among waste home appliances, refrigerator comprise 30.7%, television 37.8%, washing machine 22.9% and air conditioner 0.3%. Local government collected 46.2% of waste home appliances, producer and agent collected 49.7%, recycling center 4.1%. Seventeen percentage of waste home appliances are reused, 65% are recycled, and 18% are landfilled or incinerated. To improve the recycling activity of waste of home appliances, it is important to establish private reuse and recycling organization. It is also necessary to improve waste deposit and refund system for efficient recycling by decent financial support. Extension of a term of usage is another method to minimize waste home appliances. Finally, intensive education for consumer is necessary for waste minimization. Some portion of recycling and treatment cost can be allocated to the local government and large private business can shred and recycle waste home appliances.

• Science of Emotion and Sensibility
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• v.9 no.4
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• pp.331-339
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• 2006

PPL(Product Placement) of visual media can change the purchasing behavior of College students. This study aimed to investigate the differences in consumer's conception about PPL among college students and to analyze the relationship between the PPL conception ant fashion innovation/fashion sensitivity of students, resulting into their real purchasing behavior. We surveyed to about 189 college students living near Seoul, with questionnaire about PPL conception, purchase of PPL clothing, satisfaction on PPL clothing, fashion innovation, opinion about PPL, PPL apparel brand to recall, etc. According to dichotomy of college students by fashion innovation, as higher fashion innovative they were, they paid more attention on PPL clothing while watching TV or movie, and they also could recall more PPL apparel brands, and they purchased more PPL clothing. While the students with low fashion innovation had references from the opinion of friends or around people when purchasing their clothing, the students with high fashion innovation did from fashion magazine or PPL clothing. The students who thought that PPL was important and effective on clothing purchasing behavior, answered that their preference to PPL bran4, to the company, and to the product had increased positively, but not to the actor/actress.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.41-52
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• 1999

Recently, much literature has surveyed the economic effects of transportation investment, focusing on the relationship between transportation infrastructure investment and economic development. Although the conventional views assume that transportation investment stimulates economic growth, the results of recent studies are not conclusive and in some cases reject the conventional views. The contradictory results are linked with double counting Problem and Keynesian/Neo-classical economics theory. This article investigates the economic effects of road transportation with regard to freight transport using Stated Preference technique. This study examines, in particular, the value of time saving for freight which has been rarely studied in this area. In the first part, the value of time saving, excluding the value for driver and operating cost, is theoretically investigated through the model of continuous review system and periodic review system. At last, the empirical study using the Seated Preference technique shows the value of time saving for freight and the value of reliability, compared with other studies and the value of those in COBA. The result makes us conclude that road investment produces the secondary effects as well as the direct benefit such as time saving for passengers, operating cost saving. and accident cost reduction. The secondary effect includes the contribution to economic development.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.663-669
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• 2016

This study was conducted to analyze the nutrient compositions of stem and fruit of Opuntia ficus-indica var. saboten (OF) and Opuntia humifusa (OH). The results of the two-way analysis of variance test indicated that the parts, varieties and parts*varieties had influence on nutrient content except crude protein, soluble dietary fiber, Fe, Se, I, vitamin E, niacin and vitamin C. Moisture and crude ash content was higher in stem than in fruit, while crude lipid and insoluble dietary content was higher in fruit than in stem. Mineral content revealed that K (1,313.67 mg% in OF, 1,351.38 mg% in OH) was the highest in fruit and Ca (5,146.29 mg% in OF, 1,388.19 mg% in OH) was the highest in stem. Vitamin C was the most abundant vitamin in the fruit of OF (199.98 mg%) and OH (187.12 mg%). Polyunsaturated fatty acid was the highest among fatty acids (66.9~70.1%), with higher content in the stem (753.89 mg%) than fruit (578.01 mg%) in OF, while higher in the fruit (1,093.63 mg%) than stem (475.07 mg%) in OH. Moisture, crude protein, Mg, Se and riboflavin was higher in OF than OH; whereas, crude lipid, insoluble dietary fiber, total dietary fiber and monounsaturated fatty acid were higher in OH than OF. These results indicated that OF and OH could be a good food source for Ca, K and Vitamin C. Also, different nutrient content by parts and varieties, can be helpful in choice of parts or varieties for consumer purposes.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.603-612
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• 2014

According to the microbiological standard, Staphylococcus aureus, Clostridium perfringens and Listeria monocytogenes should not be detected in milk and egg products in Korea. Refrigerated food such as milk must be kept under $10^{\circ}C$ at retail markets. However, temperature abuse of refrigerated foods at such markets is often observed. We compared the growth and survival kinetics of S. aureus and C. perfringens at 10 and $15^{\circ}C$, and the growth kinetics of L. monocytogenes at 4 and $10^{\circ}C$ in whole and skim milk and ready-to-eat (RTE) quail eggs to evaluate their growth possibilities at retail markets. Regardless of storage temperature, the level of S. aureus reached the maximum level ($10^8-10^9CFU/ml$) in whole milk, non-fat milk and RTE quail eggs within the expiration date. Even low contamination levels of S. aureus (10 CFU/mL) grew rapidly in milk and quail eggs to reach the maximum level within the shelf life. Survival of C. perfringens in whole milk was greater than that in non-fat milk, indicating that the fat content in milk influences the survival of C. perfringens. For L. monocytogenes, the population in milk increased by 0.5-1 log CFU/mL at $4^{\circ}C$, while the populations reached the maximum level at $10^{\circ}C$ within the expiration date, regardless of initial contamination levels. In quail eggs, L. monocytogenes grew to the maximum level within the expiration date (60 days) at both temperatures. S. aureus and L. monocytogenes must be controlled to be negative, and proper temperature management should be emphasized at retail markets to protect the consumer. Since C. perfringens did not grow in milk and RTE quail eggs, there is no risk due to the growth of C. perfringens in these products at retail markets.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.606-614
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• 2018

It is important to understand how marbling traits and tenderness differ among beef steaks from the carcass grading site and other regions within the longissimus thoracis (LT) muscle, as these characteristics are closely associated with consumer acceptability and willingness to purchase. Thus, the aim of this study was to compare the marbling fleck traits and objective tenderness parameters in the groups classified by the coarseness index (CI) of marbling fleck (high and low groups) at the carcass grading site ($13^{th}$ thoracic vertebra; 13T) and three different locations (13T, 9T, and 6T) within the LT muscle from well-marbled (marbling score 7 to 9) Hanwoo steer. Image analysis showed that the longitudinal locations had a significant effect on marbling fleck traits. The total area of large marbling fleck divided by the total marbling area (coarseness) was higher at the central region (13T to 12T) compared to the front thoracic region (6T to 5T) in the high CI group (0.23 vs. 0.17, p<0.05), whereas no significant differences were observed in the total number of marbling fleck within the LT muscle in the high or low CI groups (p>0.05). Location effect on objective tenderness parameters within the LT muscle was somewhat limited, although the high CI group had a lower Warner-Bratzler shear force (WBS) value than did the low group (p<0.05). Taken together, the degree of coarseness of marbling fleck decreased from the carcass grading site to the front thoracic site, whereas the objective tenderness parameters, including WBS and hardness, of the grading site did not differ from the other regions within the LT muscle.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.155-161
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• 2012

The goal of this study was to investigate the chemical and microbiological characteristics of kimchi products distributed in Japan (5 brands, J-products) and Korea (2 brands, K-products). When their average analyses were compared, J-products showed higher values in pH, total sugar and acetic acid contents, while K-products showed higher values in number of lactic acid bacteria, sugar alcohol and lactic acid contents including textural hardness or chewiness. In addition, the analysis showed great variation in composition levels regarding pH, total sugar and acetic acid contents of J-products, and this fact revealed that different manufacturing processes are being attempted in Japan. Interestingly, some J-products had high concentrations of acetic acid with little mannitol, as this result implies that some manufacturers in Japan produce kimchi by adding acetic acid or lactic acid to control the rate of lactic acid fermentation. The result of this study elucidates the Japanese consumer's taste preference as well as the manufacturing processes in Japanese companies.

• Journal of Energy Engineering
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• v.26 no.3
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• pp.131-136
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• 2017

Automobile engine oil is the most important lubricant for operating as the engine is started. Recently, manufacturers of the automotive industry and lubricants are considerably improving the quality of oil with additive to extend change cycle period. Most customers are recommended genuine oil among different types from shop expert. Through this report we suggest another reference point for consumer to pick highly efficient lubricant. This report is investigated oil compounds to compare with 6 different automotive considering actual running condition for 7 months. we conducted experiment from physical and chemical perspectives. In the field, through various experiments oil compounds between mineral oil and synthetic oil are largely distinguished in oxidation, viscosity, fluid and TBN. These are influenced by engine part wear as piston, bearing etc. Comparing various investigation with different oil the performance of synthetic oil is shown better condition in flash point, oxidation stability and also found less in change pollutant iron, Al compounds. Additives of oil show clear difference Ca level in detergent-dispersant both mineral oil and synthetic oil. And Zn in extreme pressure additives and P in Lubricity improver make no difference to both.