• 한국해양공학회지
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• 제34권2호
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• pp.55-65
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• 2020

A review of the 2nd generation of intact stability by the International Maritime Organization is performed. The main issues with the new stability criteria are reviewed. In particular, the physical background and related mathematical formulations of the pure loss of stability and parametric roll are summarized. Based on a literature review, benchmark calculation results for 17 different types of ships are discussed, and the final results are in excellent agreement with our physical expectations. Some relatively serious design problems are found in the application of the new stability criteria to sample ships built in Korea, and possible technical solutions are proposed, which have to be improved in the coming years.

• KIEE International Transactions on Power Engineering
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• 제4A권2호
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• pp.58-68
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• 2004

This paper presents an optimal routing algorithm (ORA) for maximizing voltage stability as well as for minimizing power loss in radial power systems. In the proposed ORA, a novel voltage stability index (VSI) for real-time assessment is newly introduced based on the conventional critical transmission path framework. In addition, the suggested algorithm can automatically detect the critical transmission paths resulting in voltage collapse when additional real or reactive loads are added. To implement an effective ORA, we have developed an improved branch exchange (IBE) method based on a loss calculation index and tie-branch power flow equations, which are suggested for real-time applications. The proposed algorithm has been tested with IEEE test systems as well as a large-scale power system in Korea to demonstrate its effectiveness and efficiency.

• 한국환경보건학회지
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• 제36권3호
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• pp.171-181
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• 2010

Semivolatile aerosols exist as vapor and particles at the same time in room temperature and each phase has different intake and uptake mechanisms. This characteristic requires substantial consideration during exposure assessment of semivolatile aerosol. Some sampling methods for solid particles pose high possibility of evaporative loss during sampling. Therefore, when establishing sampling strategy for them, the factors affecting the phase distribution of semivolatile aerosol should be counted including semivolatile aerosol of interest and sampling methods used. Evaluation for phase distributions of semivolatile aerosols is also recommended. Metalworking fluids, pesticides, asphalt fumes, diesel exhaust, and environmental tobacco smoke are common health-related semivolatile aerosols in workplaces.

• 한국안전학회지
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• 제10권2호
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• pp.97-104
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• 1995

To evaluate readily the effect of unconfined vapor cloud explosion(UVCE) having high possibility of accident and risk in chemical industries, the expert system of UVCE was developed and its applicability on a real accident was analyzed. We found that the hazard of UVCE could be well evaluated from the TNT equivalency model and the empirical loss data produced by overpressure for chemical facilities. By using the developed expert system, the size of vapor cloud, the quantity of vaporization, the released energy, the overpressure range from explosion point, and the impact damage of each installation could be estimated respectively. Also, probable maximum loss and catastrophic loss potential for real accident( cyclohexane release in Flixborough Nypro company) were estimated and compared with damages of the accident. As a result, the developed expert system could be well applicable to real accident.

• 한국안전학회지
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• 제26권4호
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• pp.96-101
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• 2011

In previous studies, a system was developed for classifying items of uninsured cost and for generating factors and formulas by item for calculating accident loss costs. However, the loss cost of stopped production was not considered when the system was being developed. In addition, the system which was developed in previous studies had problems such as input error and data collection, owing to numerous input items. Therefore, this study developed a Revised system which considers the loss cost of stopped production, and a Simple system for improving the problems in input errors and data collection. In this study, unquantifiable factors were not considered. Further study that takes these factors into consideration is necessary.

• Structural Engineering and Mechanics
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• 제27권3호
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• pp.347-363
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• 2007

Assessment of structural behaviour of corrosion affected structures is an important issue, which would help in making certain decisions pertaining to the inspection, repair, strengthening, replacement and demolition of such structures. The paper presents formulations to predict the loss of weight and the loss of cross-sectional area of the reinforcing bar undergoing corrosion based on the earlier study carried out by the present authors (Bhargava et al. 2006). These formulations have further been used to analytically evaluate the ultimate bending moment and ultimate shear force capacity of the corroded concrete beams. Results of the present study indicate that, a considerably good agreement has been observed between the experimental and the analytically predicted values for the weight loss and reduction in radius of the corroded reinforcing bars. A considerably good agreement has also been observed between the experimental and the analytically predicted values of ultimate bending moment and ultimate shear force capacity for the corroded concrete beams.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1996년도 학술발표회
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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.

• Toxicological Research
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• 제18권1호
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• pp.1-11
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• 2002

3-Monochloro-1,2-propanediol(3-MCPD) is currently being a matter of concern because of its toxicity. 3-MCPD produced during the acid hydrolysis of soybean products has been reported to be mutagenic, neurotoxic, nephrotoxic and spermatotoxic. Howerer, the carcinogenicity of 3-MCPD is a controversial issue over the past several decades. 3-MCPD characteristically showed a variety of toxicities in reproductive system such as, decrease in sperm number and sperm motility, infertility, loss of sperm function, and weight decrease in ovary. Due to the toxicity of 3-MCPD, exposure to 3-MCPD has been proposed to be reduced to as low a level as technologically feasible. 3-MCPD can be detected in soy sauce or non-soy sauce products. The legal limit for 3-MCPD this year has been suggested to be 20 ppb（$\mu\textrm{g}$/kg）in the European Community. In Korea, the permissible level of 3-MCPD is expected to be 0.3 ppm. In this study, 3-MCPD was toxicologically evaluated in terms of risk assessment in humans.

• 한국환경과학회지
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• 제8권4호
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• pp.457-464
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• 1999

To develop managing guidance of occupational noise exposure for metal working facility, we have studied about drafting contour map of noise exposure, methods of noise assessment and actual calculation method of time weighted noise exposure. Therefore we have suggested that contour maps of noisy workplace are very important for controlling metal working fluid facility and two kinds of noise assessment method, so called, personal andstatic exposure are necessary to avoid argument between workers and managing group. Finally we would like recommend that the Korean specification of noise exposure should be modified to protect ONIHL(oocupational noise induced hearing loss).

• International Journal of Safety
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• 제6권2호
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• pp.8-12
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• 2007

This study includes a case study among plastic process manufacturing companies, based on which, the currently used 4M method is applied in terms of machine, media, man, and management, to conduct quantitative risk evaluation, and thus to contribute to reducing human and material loss as well as preventing accidents in industrial fields. The result of this study is analyzed based on the 4M-risk assessment to find out the hazardous risk elements, and the quantitative evaluation made it predictable the value of risk(frequency $\times$ intensity) in such classified levels as serious risk, critical risk, and intolerable risk. Further, Among the businesses with hazardous risk elements and high frequency of industrial disaster, risk analysis was conducted for each process, and as a result, 38 cases among 76, including those of serious risk, critical risk, and intolerable risk, were improved, and the risk was reduced. Besides, it is thought that with the engineering approach with 4M-Risk Assessment, the attempt to improve safety level contributes to prevention of accidents.