• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.316-322
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• 2005

In this study, the concentration of 17 dioxin congeners in the soil samples near a waste incinerator with respect to distance from incinerator and wind directions were investigated. The effect of PCB source was investigated using the cluster analysis method. The total concentration and I-TEQ concentration of dioxin ranged from 31.065 to 7,257.499 pg/g(dry weight) and from 0.099 to 35.191 pg I-TEQ/g(dry weight.), respectively. There was a weak correlation(not statistically significant) observed between soil concentration and wind direction, and the distance from the incinerator. The reason may be due to the presence of the local combustion sources other than the target incinerator. The fraction of PCDFs and PCDDs was also examined to study the effect of incinerator. The fraction of PCDFs was decreased with the distance from the incinerator. The influence of target incinerator was found within a 500-meter radius. The high concentration in the for site was due to small incinerators and the use of agricultural chemicals such as PCP. To investigate the relationship between soil near the incinerator and the sources, the cluster analysis was conducted using the congener pattern. As a result soil samples were divided into four groups and were qualitatively estimated the influence of sources such as incinerator and PCP by comparing the congener pattern of each roups. It was thought that a cluster analysis was a useful statistical method for the source estimation of dioxin.

• Journal of environmental and Sanitary engineering
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• v.1 no.1 s.1
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• pp.69-79
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• 1986

This studies were carried out to investigate the high infection sites from various specimens, cultural isolation on the susceptible media and specific antibody titres of M. pulmonis in experimental 310 mice and 330 rats obtained from two breeding facilities. Efficiency of complement faxation test (CF test) for detection of M. pulmonis antibody in mice and rats were compared directly with the diagnostic cultural isolation method. 1. Isolation rates of M. pulmonis among infection sites were about 30% from the oral cavities and $40\%$ from the middle ear of mice. The rates were $100\%$from the nasal cavaties and $90\%$ from the oral cavities of rats. 2. The infection rates were $12\%$ to A group and $16\%$ to B group of mice. The rates in the rats were $55\%$ to A group and $70\%$ to B group. 3. The M. pulmonis antibody titres by CF test were $73\%$ of total 100 mice in serum dilution below 1:5 (< 1:5), and $24\%$ of total samples in antibody titres above 1:5 (> 1:5), but 3 samples were not showed anticomplementary activities. The antibody titres in rats were $35\%$ of 120 rats in below 1:5 (< 1:5), and $61\%$ of total samples in above 1:5 (> 1:5), but the remained were not showed anticomplementary activities.

• Fire Science and Engineering
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• v.30 no.6
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• pp.31-36
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• 2016

The flash point is one of the most important properties for characterizing the fire and explosion hazard of liquid solutions. In this study, the flash points of two flammable binary mixtures, n-pentanol + n-propanol and n-pentanol + n-heptanol systems were measured using a Seta flash closed cup tester. The flash point was estimated using the methods based on Raoult's law and multiple regression analysis. The measured flash points were also compared with the predicted flash points. The absolute average errors (AAE) of the results calculated by Raout's law were $1.3^{\circ}C$ and $1.3^{\circ}C$ for the n-pentanol + n-propanol and n-pentanol + n-heptanol mixtures, respectively. The absolute average errors of the results calculated by multiple regression analysis were $0.4^{\circ}C$ and $0.3^{\circ}C$ for the n-pentanol + n-propanol and n-pentanol + n-heptanol mixtures, respectively. According to the AAE, the calculated values based on multiple regression analysis were better than those based on Raoult's law.

• Journal of the Ergonomics Society of Korea
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• v.31 no.3
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• pp.445-453
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• 2012

The aim of this paper was to prove that if the risk level in combined tasks was improved through evaluation of postural load of liquid weight measurement process, the workload level and ratio of exposure time would be changed, and the time of process would be seen concurrently. Background: According to results of epidemiological studies conducted by Korea Occupational Safety & Health Agency, 122 musculoskeletal disorders occurred during 1992 to 2008, in which manufacturing industry covers 96(78.7%) of total. However, this is an insufficient level and only occupies 39% based on the South Korea's manufacturing standard industrial classification(246 industries). Method: Firstly, the number of batches weighed on one day(460min) was investigated based on the work performed and Weight measured weekly. VCR recording was taken based on the level of liquid ingredients prescribed for 1batch using the Camcorder. After dividing a 356 sec video into 1 sec using the screen capture function in Gom player, the job classification was performed by analyzing the change of working postures, which revealed 148 working postures. Time measurement was decided by time of the postures was being maintained. Then, the REBA analysis was performed for the working postures. The ratio of Exposure time was calculated based on the measurement time and REBA Score. In addition, the recommendations were designed and implementation was carried out for the working postures with REBA Score higher than 3. Finally, after the intervention, REBA measurement, time measurement, and ratio of exposure time were calculated for the comparison of works before and after improvement. Results: The number of work elements was decreased by 30.4% from 148 to 103 after improvement. The results of time measurement showed that the time was reduced by 46.3% from 356 sec to 191 sec. And the ratio of exposure time was also improved by 52.1% from 0% to 52.1% after improvement. Conclusion: The reduction of time was found to improve the productivity of management. Furthermore, because the reduction of ratio of exposure time and the improvement of workload level are the improvement of discomfort, it would contribute to the improvement of the worker's psychological working posture. Application: These results would contribute to musculoskeletal disease prevention and management performance. Further studies for other industries would be needed based on this case study.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.103-112
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• 2011

Aquatic contamination by organic pollutants has been a suspected reason for rapid decrease of amphibian populations whose embryonic and larval stages are in an aquatic environment. Amphibian embryos can be a useful model to study the ecoctoxicologial impacts of aquatic pollutants. The obtained toxicological data are useful references for the management of aquatic pollutants in public health because amphibia share many developmental events with terrestrial vertebrates including humans. Safety guidelines for the toxicological effects of aquatic contaminants of chemicals identified as hazardous should be addressed at multiple endpoints. Alkylphenols have been widely-used in agricultural, industrial, and household activities; they contaminate and can persist in aquatic environments. Exposure to alkylphenols results in endocrine disruption in aquatic animals. In this review, we summarize the developmental toxicities of alkylphenols in amphibian embryos and larva according to the exposure route, chemical concentration, duration of exposure, and affected developmental stage together with mechanisms of toxicity and typical patterns of developmental abnormality. The merits of amphibian embryos as a toxicity test model for mid- to long-term exposure to aquatic pollutants are discussed proposed.

• Korean Journal of Construction Engineering and Management
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• v.8 no.2
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• pp.118-126
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• 2007

Environmentally Sound and Sustainable Development (ESSD)" is a key word in recent years. The construction industry, have put a great influence on ergonomic and sustainable environment. Recently, "green building certifications", such as Indoor Air Quality (IAQ) and eco-friendly material regulation have been established. With this regard, new construction and aged-housing remodeling projects are required to meet these certification criteria. Apartment residents have great concern on eco-product, since many cases are reported that Sick Building Syndrome is caused by toxic substance from building materials. Aged-housing remodeling construction has a unique characteristic in that the residents are already determined prior to construction execution. Therefore, the analysis of resident's need for building materials in aged-housing remodeling is relatively easy compared to new building construction. As such, it is very important to analyze their preferences for eco-friendly materials prior to project execution. The purpose of this study is to find the needs of residents and priority of their needs. Based on their needs and priority, this paper provides a new strategy in using environment-friendly materials and maximizing their satisfaction level when aged housing remodeling is constructed. In addition, this paper provide new criteria in selecting new developed environmental materials in remodeling projects for the purpose of improving the safety and health level in construction industry.

• Journal of Ginseng Research
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• v.40 no.3
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• pp.260-268
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• 2016

Background: During the aging process, skin shows visible changes, characterized by a loss of elasticity and the appearance of wrinkles due to reduced collagen production and decreased elasticity of elastin fibers. Panax ginseng Meyer has been used as a traditional medicine for various diseases due to its wide range of biological activities including skin protective effects. Ginsenosides are the main components responsible for the biological activities of ginseng. However, the protective activities of an enzymatic preparation of red ginseng against human skin aging have not been investigated. Methods: The efficacy of an enzyme-treated powder complex of red ginseng (BG11001) in preventing human skin aging was evaluated by oral administration to 78 randomized individuals. All patients were requested to take three daily capsules containing either 750 mg of BG11001 or a placebo vehicle for 24 wk; at the end of the testing period, skin roughness, elasticity, and skin water content were measured. Results: BG11001 significantly reduced the average roughness of eye wrinkles and the Global Photo Damage Score compared with the placebo, although there were no significant differences in arithmetic roughness average between the groups. In addition, gross elasticity and net elasticity values increased, and transepidermal water loss level decreased, indicating improved skin elasticity and moisture content. Conclusion: In conclusion, enzyme-treated red ginseng extract significantly improved eye wrinkle roughness, skin elasticity, and moisture content. Moreover, enzyme-treated red ginseng extract would be useful substance as a bio-health skin care product.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.179-193
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• 2021

As pets such as dogs and cats have been accepted as family members and companions, calling them companion animals has become more and more common. As the trend of identifying companion animals with humans and treating them as members of a family is spreading, people are more concerned about food, health, and leisure for companion animals, searching for expensive products, and accelerating the growth of related businesses. This study collected data by conducting an online questionnaire targeting customers who visited online companion animal shopping malls. Data collected only for people who have purchased companion animals at least once in online shopping malls for companion animals were used for empirical analysis. Questionnaires from 205 people were collected, but a total of 198 copies were used for the analysis, excluding the questionnaire that gave an insincere response. The results are as follows. First, through exploratory factor analysis, it was confirmed that the service quality factors of the online shopping mall for companion animals consisted of four dimensions: communication-transaction, safe security, design, and information provision. Second, it was found that communication-transactions, information provision, design, and safe security, which are the service quality factors for companion animal online shopping malls, all have a significant positive (+) effect on customer satisfaction. Third, it was confirmed that customer satisfaction in online shopping malls for companion animals had a significant positive (+) effect on loyalty. Fourth, in the relationships between service quality factors (communication transaction, safety security, design, information provision) and loyalty of companion animal online shopping mall, it was confirmed that customer satisfaction has complete mediating effects.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.324-330
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• 2018

In accordance with the amendment of the Industrial Safety and Health Act of 2007, Korea completely prohibited the import, distribution and manufacture of asbestos like Europe and Japan. Accordingly, the current problem of asbestos is the safe maintenance and disposal of asbestos construction material, the disposal of asbestos, and the final disposal of asbestos building materials. In the past, Korea used 100,000 tons of asbestos every year, and the building materials using it exceeded 1 million tons per year. These asbestos building materials continued to be used until 2006, and the Ministry predicted that these materials would continue to be maintained until 2044. When the permeable hardening agent is applied to the asbestos building material installed in the pre-pretreatment step for the harmless treatment of the asbestos waste and the dismantling is carried out, the scattering of the asbestos is suppressed in the disassembling step, detoxification treatment conditions can be improved. Therefore, permeable hardeners should be stably penetrated into asbestos building materials. In this study, it is suggested that pre - pretreatment methods for the harmlessization of waste asbestos building materials with medium density level can be presented. In order to efficiently perform pre - treatment for chemical harmlessness in the future, the mixing ratio of permeable hardener and middle water Optimization is the most important factor.

• Food Science and Industry
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• v.54 no.1
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• pp.11-28
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• 2021

Air pollution caused by particulate matters (PM) has become a global issue. PM is known to threaten human health by causing respiratory and cardiovascular disease. PM can be introduced to human gastrointestinal track through food intake, causing inflammation and changes in gut microbiota. Even at low PM concentrations, prolonged exposure to PM can cause significant accumulation of PM in food products. The adsorption of PM onto food surfaces is expected to be strongly influenced by the properties of food surfaces, but few studies have been reported. This paper examines several important food surface properties that may affect the interactions between PM and food surfaces, including surface wettability, surface charge, and surface microstructure. Understanding the adsorption of PM onto food surfaces can provide useful guidance for classifying PM-sensitive foods and controlling food chains, including cultivation, processing, preservation, and cooking, to ensure food safety against PM.