• Journal of the Korea Society for Simulation
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• v.15 no.4
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• pp.119-128
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• 2006

A turnout system which permits trains to pass from one track to another is a combination of the switch, the crossing, lead rails which are necessary to connect the switch and the crossing, two guard rails and a switch machine for operating the switch. A turnout is the sole moving part among the railway components and has complex configuration, so the safety has always been raised an issue. In Korea, it is planned to adopt the high speed tilting train, which operates at the maximum speed of 200km/h, at conventional lines by the year of 2010. However, for the application of the tilting train to conventional lines, it is prerequisite to establish a stable turnout system allowing the tilting train to pass through it without reducing speed. Therefore, the improved turnout system for the speed-up of conventional lines has been developed and the prototype of the turnout system has been constructed. In this study, simulation of noise and vibration around the improved turnout system was performed in order to predict the generation level of noise and vibration due to passing of the tilting train through the turnout system.

• 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.

• Food Science and Preservation
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• v.9 no.1
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• pp.46-50
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• 2002

This study was carried out for dietary safety based on the level of pesticide residues in 17 kinds of the agricultural products (apple, cabbage, cabbage kor, carrot, cucumber, pepper, onion, potato, radish, spring onion, pumpkin, lettuce, garlic, drapwort, spinach, leek crown daisy) consumed in Kyunggi-do and Inchon-city that provided for the army. From January 1998 to December 2001, ten organochlorine pesticides in 1075 samples were analyzed by using GC-ECD. According to the results, one kind of pesticides was detected in 135(12.5%) samples, and two kinds were in 7 (5.18%). While dicofol and tetradifon was not fecund. Detection rate of pesticides were 9.02% for $\alpha$, $\beta$-endosulfan, 2.8% far chlorothalonil, 0.46% for γ-BHC, 0.40% for chlorobenzilate, 0.33% for folpet, 0.28% far DDT, 0.15% for captafol, and 0.11% for captan. Dectection ranges of pesticides were from 0.001 to 0.092 ppm for $\alpha$, $\beta$-endosulfan, from 0.003 to 0.023 ppm for chlorothalonil, from 0.003 to 0.006 ppm far γ -BHC, from 0.001 to 0.003 ppm for DDT, from 0.009 to 0.095 ppm for folpet, 0.05 ppm for captan, 0.01 ppm for captafol, and 0.008 ppm far chlorobenzilatel respectively. Consequentlyl all detected pesticide levels in samples were below maximum residue limits(MRLs) in Korea and Codex.

• Food Science and Preservation
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• v.15 no.4
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• pp.606-611
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• 2008

Myungran Jeotkal, Korean fermented seafood, and its ingredients(hot red pepper powder, ginger, garlic, and seasoning mix) were irradiated with 0, 0.5, 1.0, 2.0, and 5.0 kGy of gamma rays and stored at 4C for 4 weeks to determine changes in microbiological and sensory characteristics. Water activities of Myungran Jeotkal, hot red pepper powder, ginger, garlic, and seasoning mix were 0.89 0.56, 0.98, 0.99, and 0.07, respectively. Myungran Jeotkal was observed to be initially contaminated. Total aerobic bacteria, yeast and mold, and coliform levels were 6.7, 4.3, and 3.6 log CFU/g, respectively. Irradiation at 2 kGy afforded approximately a 4 log reduction in total aerobic bacteria, and a 3 log drop in both yeast and mold levels and coliform bacteria(P<0.05). No viable microbial cells were detected in Myungran Jeotkal after 5 kGy of irradiation(at a detection limit of 101 CFU/g). The total aerobic bacterial level in red pepper powder was 6.3 log CFU/g and this component, of the tested ingredients, contributed most to the microbial contamination of Myungran Jeotkal. The initial count of total aerobic bacteria, 6.3 log CFU/g, was significantly reduced to 4.5 log CFU/g after irradiation(P<0.05). Sensory evaluation showed that gamma irradiation of up to 5.0 kGy did not adversely affect overall acceptability of Myungran Jeotkal or its ingredients during cold storage. Therefore, gamma irradiationwas effective to extend the shelf-life of Myungran Jeotkal.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.177-188
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• 2001

Mastitis is one of the most significant cause of economic loss to the dairy industry. Especially, Staphylococcus aureus is a major contagious mastitis-causing pathogen in dairy cattle. Because of its high transmission rate and resistance to antibiotic therapy, staphylococcal mastitis presents a constant threat to the dairy industry. Staphylococcal enterotoxin C(SEC) produced by S aureus has been known as one of superantigens which are able to stimulate a large proportion of T lymphocytes independently of their antigenic specificity. In this experiment, we have conducted preliminary studies with mice and lactating cows to evaluate the immunogenicity and safety of the experimental vaccine consists of SEC mutant antigen on controlling the bovine mastitis associated with S aureus infections. The average value of somatic cell counts in quarter milk, isolation rate of S aureus were consistently decreased in SEC-SER vaccinated groups, whereas antibody titers were highly increased in SEC-SER vaccinated groups. Peripheral blood were also collected from the lactating cows to determine the proportion of leukocyte subpopulation associated with humoral immunity(HI) and cell mediated immunity(CMI). Proportion of leukocyte subpopulation expressing $BoCD2^+$(total T lymphocyte), $BoCD4^+$(T helper cell), $BoCD8^+$(T cytotoxic/suppressor cell) and NonT/NonB lymphocyte which are involved in CMI in SEC-SER vaccinated groups were decreased for the initial stage after first vaccination and then increased from ten weeks after first vaccination maintaining elevated level till 14 weeks after vaccination. In contrast, proportion of monocyte, MHC class II and B lymphocyte which are associated with the production of primary immune response in SEC-SER vaccinated groups were increased for the initial period and then decreased from ten weeks after first vaccination. We present evidence that vaccination of SEC-SER mutant antigen in lactating cows induced a significant proliferation of bovine T lymphocytes. These results suggest that SEC-SER mutant antigen used in this experiment might be one of potential immunogen in developing innovative vaccine against bovine IMI associated with S aureus. Additional challenge trials should be carried out to evaluate substantial protection against S aureus under the commercial farm conditions.

• Fire Science and Engineering
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• v.33 no.4
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• pp.16-27
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• 2019

A burning test was conducted on the smoke and combustion gases generated from cypress wood treated with sodium silicate, 3-aminopropyltrimethoxysilane sol, 3-(2-aminoethylamino)propylmethyldimethoxysilane sol, and 3-(2-aminoethylamino) propyltrimethoxysilane sol. The silicone compound sol was applied to each of the cypress wood specimens three times with a brush. The smoke and combustion generation gas were analyzed using a cone calorimeter (ISO 5660-1) and the smoke was also evaluated by applying new smoke risk assessment method. The smoke performance index (SPI) of the cypress treated with silicone compound increased 1.66 to 8.42 times and the smoke growth index (SGI) was 11.8 to 88.2%, respectively. The smoke intensity (SI) is expected to be 1.0~50.5% lower than that of the base specimens, resulting in lower smoke and fire hazards. The third maximum carbon monoxide (CO_peak) concentration of the specimens treated with silicone compounds was 22.5~33.3% lower than that of the base specimens. On the other hand, it produced potentially fatal toxicity that was 1.48~1.72 times higher than the US Occupational Safety and Health Administration (OSHA) acceptance standard (PEL). Cypress wood itself produced a high carbon monoxide concentration, but the silicon compound played a role in reducing this level.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.401-404
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• 2008

Bridges are exposed to very severe environment and experience, as service life increased, elevated traffic load and traffic flow, in addition to natural disasters. In comparing to other road structures, bridges may cause more significant damage, such as human-involved accidents, to the society in the event of collapse. A certain level of service shall be necessarily secured to assure the minimum safety of users. The cost for manage and preserve bridges will increase gradually and more restrictions will be loaded to efficiently distribute the limited resources, such as monetary budget and human resource etc. In order to enhance performance and serviceability of bridges with the limited resource, asset management technique has been applied into the bridge management system, which capitalizes the road infrastructures including bridges and assess them in accordance with the government finance report. In the application of asset management, there must be a tool for assess the performance of bridges and this study introduces the basic information on the definition and role of performance measures for asset management for bridges.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.1
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• pp.59-68
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• 2014

The public's access to the disposal facilities should be restricted during the institutional control period. Even after the institutional control period, disposal facilities should be designed to protect radiologically against inadvertent human intruders. This study is to assess the effective dose equivalent to the inadvertent intruder after the institutional control period thorough the GENII. The disposal unit was allocated with different kind of radioactive waste and the effects of the radiation dose to inadvertent intruder were evaluated in accordance with the institutional control period. As a result, even though there is no institutional control period, all were satisfied with the regulatory guide, except for the disposal unit with only spent filter. However, the disposal unit with only spent filter was satisfied with the regulatory guide after the institutional control period of 300 years. But the disposal unit with spent filter mixed with dry active waste could shorten the institutional control period. So the institutional control period can be reduced through the mixing the other waste with spent filter in disposal unit. Therefore, establishing an appropriate plan for the disposal unit with spent filter and other radioactive waste will be effective for radiological safety and reduction of the institutional control period, rather than increasing the institutional control period and spending costs for the maintenance and conservation for the disposal unit with only spent filter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1035-1040
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• 2015

4-Hexylresorcinol (4-HR) has been used for prevention of melanosis in shrimp. Recently, 4-HR in EU and other countries was authorized with maximum residue levels of 1~2 mg/kg but remains unauthorized in Korea. Therefore, the aim of this study was to investigate the effect of 4-HR on melanosis inhibition and residual levels in Korean shrimp according to various concentrations and soaking times. We previously reported that the HPLC-FLD method can be used for detection of 4-HR at maximum levels of 1~2 mg/kg in shrimp. Our results show that residual levels of 4-HR in peeled and unpeeled shrimps were in the range of 0.86 to 13.46 mg/kg and 0.02 to 2.33 mg/kg, respectively. In addition, 4-HR treatment at concentrations of 10 and 20 mg/L for 72 h were effective for inhibition of melanosis in peeled shrimp compared with unpeeled shrimp. These results provide basic data for the establishment of guidelines and regulation related to 4-HR.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.632-639
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• 2015

Working in the forest would require a wide range of skills and experience for specific tasks which involve with a high level of risks to worker's safety. However, there has been a concern on the current standard wage system for forest workers because it does not effectively reflect the characteristics of typical working conditions in the forest. In addition, the current standard wages for forestry workers was estimated based on the construction industry's wage system. Therefore, the purpose of this study is to assess a current wage system through the mail survey method and to develop a new wage system for forest worker which effectively reflects skill sets and experience required for successful completion of the work in the forest. We mailed the survey questionnaire consisting of 19 questions to 659 forest workers and received 188 responses resulting in a 28.5% response rate. The results showed that the current average optimal wages of forest worker, special worker and feller were 97,680won/day, 127,559won/day and 152,403won/day, respectively though there were variations depending on the regions. In developing the new standard wage system, this study suggest the current work types(worker, special worker and feller) could be divided into 5 work types (forest-environment workers, forest operations in beginner, forest operations in intermediate, forest operations in advanced and forest equipment operator) reflecting specialty of forest operation thereby stabilizing the new wage system for forest workers.