• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.410-417
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• 2014

Berries and green tea are underutilized in the food industry despite their great potential as a functional food ingredients. The purpose of this study was to determine the extraction conditions under which total phenolic contents and antioxidant activities of berry and green tea extracts are maximized. Extracts produced using 0-80% ethanol and temperatures ranging from $5-65^{\circ}C$ were evaluated for total phenolic content (TP), as well as for DPPH and ABTS radical-scavenging activities by using response surface methodology. Both ethanol and temperature had significant effects (p<0.05). Ogaja extract produced at $67^{\circ}C$ by using 33% ethanol yielded maximum TP, ABTS, and DPPH values of 23.74 mg GAE/g, 19.77, and 25.04 mg VCE/g, respectively. Optimum conditions for mulberry and raspberry extraction were found to be $65^{\circ}C$ by using 69% and 40% ethanol, respectively. Mulberry and raspberry extracts had TP, DPPH, and ABTS values of 20.74 mg GAE/g, 23.55, and 35.44 mg VCE/g, and 26.08 mg GAE/g, 39.93, and 55.60 mg VCE/g, respectively. Green tea extraction at $57^{\circ}C$ by using 43% ethanol was found to be optimal, yielding TP, ABTS, and DPPH values of 101.15 mg GAE/g, 171.38, and 177.56 mg VCE/g, respectively.

• Industry Promotion Research
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• v.9 no.2
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• pp.37-44
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• 2024

This study selected the worst-case scenario for fireball and vapor cloud explosion (VCE) of a styrene monomer storage tank installed in a petrochemical production plant and performed damage prediction and accident impact analysis. The range of influence of radiant heat and overpressure due to fireball and vapor VCE during the abnormal polymerization reaction of styrene monomer, the main component of the mixed residue oil storage tank, was quantitatively analyzed by applying the e-CA accident damage prediction program. The damage impact areas of radiant heat and explosion overpressure are analyzed to have a maximum radius of 1,150m and 626m, respectively. People within 1,150m of radiant heat of 4kW/m2 may have their skin swell when exposed to it for 20 seconds. In buildings within 626m, where an explosion overpressure of 21kPa is applied, steel structures may be damaged and separated from the foundation, and people may suffer physical injuries. In the event of a fire, explosion or leak, determine the risk standards such as the degree of risk and acceptability to workers in the work place, nearby residents, or surrounding facilities due to radiant heat or overpressure, identify the hazards and risks of the materials handled, and establish an emergency response system. It is expected that it will be helpful in establishing measures to minimize damage to workplaces through improvement and investment activities.

• Journal of IKEEE
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• v.15 no.1
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• pp.37-42
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• 2011

In this paper, the high-voltage novel devices have been fabricated by 0.35 um BCD (Bipolar-CMOS-DMOS) process. Electrical characteristics of 20 V level BJT device, 30/60 V HV-CMOS, and 40/60 V LDMOS are analyzed. Also, the vertical/lateral BJT with the high-current gain and LIGBT with the high-voltage are proposed. In the experimental results, vertical/lateral BJT has breakdown voltage of 15 V and current gain of 100. The proposed LIGBT with the high-voltage has breakdown voltage of 195 V, threshold voltage of 1.5 V, and Vce, sat of 1.65 V.

• Journal of the Korean Institute of Gas
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• v.14 no.2
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• pp.15-21
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• 2010

The demand of gas as an eco-friendly energy source has being increased. With increasing the LPG demand, the number of LPG filling station. In this work, the influence on over-pressure caused by Vapor Cloud Explosion in gas station was calculated by using the Hopkinson's scaling law and injury effect by the accident to a human body was estimated by applying the probit model. As a result of the injury estimation conducted by using the probit model for leakage 10% of 20ton storage tank. The distances from LPG station for death and tympanum rupture are 36.5 and 290 meters, respectively.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.319-327
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• 2023

This study analyzes the risks of explosions of small LPG storage tanks installed at highway rest areas. For this purpose, the ranges of the effect of thermal radiation and overpressure caused by the BLEVE(Boiling Liquid Expansion Vapor Explosion)and VCE(Vapor Cloud Explosion) of a 2900-kg small LPG storage tank installed at highway rest areas were quantitatively evaluated by applying the Areal Location of Hazardous Atmospheres program. The ranges of influence of the derived explosion overpressure and thermal radiation were found to have a maximum radii of 336 m and 423 m, respectively. The study determined that those within 269 m could be severely injured by an explosion overpressure of 3.5 psi, and fatalities from thermal radiation of 10 kw/m² could occur within 192 m of the exploded storage tank. The safety management plan for the LPG storage tank was discussed while considering the auxiliary facilities of highway rest areas and the extent of the damage impact. These research results will help improve safety accident prevention regulations considering the environment and facilities of the rest areas as well as the safety management of small LPG storage tanks installed at highway rest areas.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.11a
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• pp.121-124
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• 1998

화학공업은 고도의 기술집약적 장치산업이며 가연성 및 반응성이 높은 물질을 고온, 고압하에서 사용ㆍ저장하고 있기 때문에 화재 및 폭발사고의 가능성이 항상 잠재하고 있다. 특히, 화학공장에서 사용하는 대부분의 물질이 BLEVE (Boiling Liquid Expanding Vapor Expansion)와 VCE(Vapor Cloud Explosion)를 유발할 수 있는 가연성 물질이므로 사회적 문제를 야기할 수 있는 중대재해가 발생할 수 있다. (중략)

• Journal of Educational Research in Mathematics
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• v.26 no.2
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• pp.287-307
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• 2016

In this study, mathematics exams for university entrance in the USA, the UK, Australia, Singapore, and Japan are investigated. We look into SAT, ACT and AP-course in the USA, GCE A-level test in the UK and Singapore, VCE in Australia, and UECE (University Entrance Center Exam) and individual university's admission tests in Japan. Those exams are analyzed in terms of exam system, mathematical contents, types of items, and testing time. Based on the result five issues on university entrance exam system in Korea are drawn out: types of tests, mathematical contents, item types, sub-items, and opening tests results to the public.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.136-144
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• 2010

Two types of informations are used for content-based video copy detection: spatial information and temporal information. The spatial information means content-based image fingerprint. This image fingerprint must have following characteristic. First, Extraction is simple. Second, pairwise independence for random selected two images. At last, Robust for modifications. This paper proposed image fingerprint method for contents based video copy detection. Proposed method's extraction speed is fast because this method's using block average, first order differentiation and second order differentiation that can be calculated add and minus operation. And it has pairwise independence and robust against modifications. Also, proposed method feature makes binary by comparisons and using coarse to fine structure, so it's matching speed is fast. Proposed method is verified by modified image that modified by VCE7's experimental conditions in MPEG7.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.246-256
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• 2017

Purpose: This study aimed to investigate the association of total dietary antioxidant capacity (TAC) with oxidative stress and metabolic markers among patients with metabolic syndrome according to gender. Methods: A total of 346 subjects aged 30~59 years with two or more risk factors of metabolic syndrome were recruited from a general hospital near Seoul in South Korea between 2010 and 2012 based on data from the medical checkup. Biochemical indices for oxidative stress and metabolic markers were measured. Food consumption data from 3-day food records were linked with the antioxidant capacity database for commonly consumed Korean foods to estimate individual's TAC. Results: Average dietary TAC of the study subjects was 132.0 mg VCE/d/1,000 kcal in men and 196.4 mg VCE/d/1,000 kcal in women. Levels of ${\gamma}$-glutamyltransferase (GGT), systolic blood pressure, diastolic blood pressure, and blood triglycerides were reduced significantly according to increasing TAC in men, but there was no significant trend in women. Intakes of total flavonoids and carotenoids were significantly negatively correlated with GGT (p < 0.05) and d-ROMs (p < 0.01) in men, whereas those of ${\alpha}$-tocopherol (p < 0.05) and ${\gamma}$-tocopherol (p < 0.05) were positively correlated with biological antioxidant potential (BAP) in women. The odds ratio of high oxidative stress indices and abnormal metabolic markers according to TAC level were not significant in either men or women. Conclusion: The results show that dietary TAC was partially associated with oxidative stress and metabolic markers among patients with metabolic syndrome. Further research is required for elucidating the association between dietary TAC and incidence of metabolic syndrome and chronic diseases within a large population in prospective studies.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1996.11a
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• pp.37-42
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• 1996

The assessment of catastrophic accidents such as BLEVE, vapor cloud explosion, and toxic material releases in the chemical process industries(CPI) shall be carried out according to the Requirement of PSM/SMS enforced by Korea Government Agencies, but reasonable models are not proposed for the practical application. The traditional models, TNT Equivalency Model, are well-known and helpful for the assessment of vapor cloud explosion. However, the estimated-damage-area using the traditional model has much more deviations comparing to the real damage caused by vapor cloud explosion suffered before. These are why an expert system for the assessment of vapor cloud explosion has been developed, which is based on theoretical, statistical and experimental data, and it would be helpful for CPI to evaluate the damage-area in case of vapor cloud explosion.