• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.56-63
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• 2015

Gas explosion accidents could cause a catastrophe. we need specialized and systematic accident investigation techniques to shed light on the cause and prevent similar accidents. In this study, we had performed LNG explosion simulation using AUTODYN which is the commercial explosion program and predicted the damage characteristics of the structures by LNG explosive power. In the first step, we could get LNG's physical and chemical explosion properties by calculation using TNT equivalency method. And then, by applying TNT equivalency value about the explosion limit concentration of LNG on the 2D-AUTODYN simulation, we could get the explosion pressure wave profiles (explosion pressure, explosion velocity, etc.). In the last step, we performed LNG explosion simulation by applying to the explosion pressure wave profiles as the input data on the 3D-AUTODYN simulation. As a result, we had performed analyzing of the explosion characteristics of LNG in accordance with concentration through the 3D-AUTODYN simulation in terms of the explosion pressure behavior and structure's destruction and damage behavior.

• Journal of Ocean Engineering and Technology
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• v.28 no.1
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• pp.12-19
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• 2014

Tsunamis are ocean waves generated by movements of the Earth's crust. Several geophysical events can lead to this kind of catastrophe: earthquakes, landslides, volcanic eruptions, and other mechanisms such as underwater explosions. Most of the damage associated with tsunamis are related to their run-up onto the shoreline. Therefore, effectively predicting the run-up process is an important aspect of any seismic sea wave mitigation effort. In this paper, a numerical simulation of the behaviors of a floating body near a quaywall during a tsunami is conducted by using a particle method. First, a solitary wave traveling over shallow water with a slope is numerically simulated, and the results are compared with experiments and other numerical results. Then, the behaviors of floating bodies with different drafts are investigated numerically.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.22
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• pp.201-226
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• 2004

P & I Clubs are mutual and non-profit making insurers which offer shipowners cover for the contractual and third-party liabilities. Whereas most shipowners obtain P & I insurance to cover for their legal liabilities, they also obtain hull insurance to cover against damages to the hull of their vessels from commercial hull insurers. P & I insurance was distinguished from hull insurance in respect that it offered non-limited cover to shipowner member, but there was a serious debate between P & I Clubs in respect of the non-limited cover. A compromise by International Group of P & I Clubs eventually emerged under which, with effect from 20 February 1997, a financial cap was placed on the obligation of each shipowner to pay catasrophe calls to his club(20% of each ship's property limitation fund under 1976 Limitation Convention). Nevertheless many shipowners felt that this new cap on their potential catastrophe call had been set still too high, while others resisted any reduction in the figure established by the compromise. In the Meantime, the European Commission issued a Statement of Objections in June 1997, in which it indicated its objections with a compulsory single limit common th all the Group clubs as high as the 1997 compromise. Eventually the board of all the Group clubs decided that the figure of 20% of the Limitation Convention per ship property funds should be dropped down to 2.5% from 20 February 1999.

• Industrial Engineering and Management Systems
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• v.13 no.4
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• pp.398-407
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• 2014

Shortages and delays in a humanitarian logistics system can contribute to the pain and suffering of survivors or other affected people. Humanitarian logistics budgets should be sufficient to prevent such shortages or delays. Unlike commercial supply chain systems, the budgets for relief supply chain systems should be able to satisfy demand. This study describes a comprehensive model in an effort to satisfy the total relief demand by minimizing logistics operations costs. We herein propose a strategic model which determines the locations of distribution centers and the total inventory to be stocked for each distribution center where a flood or other catastrophe may occur. The proposed model is formulated and solved as a mixed-integer programming problem that integrates facility location and inventory decisions by considering capacity constraints and time restrictions in order to minimize the total cost of relief operations. The proposed model is then applied to a real flood case involving 47 disaster areas and 13 distribution centers in Thailand. Finally, we discuss the sensitivity analysis of the model and the managerial implications of this research.

• Environmental Engineering Research
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• v.20 no.4
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• pp.356-362
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• 2015

Many burial sites were constructed in a short time to prevent the rapid spread of foot and mouth disease in infected livestock carcasses in Korea. More than 4,700 carcass burial sites were constructed in 2011. Approximately seven million poultry and 3.5 million livestock, including cattle and swine, were buried on farmland. Some burial sites were suspected of leachate leakage and were excavated and carcasses redisposed in a bioaugmentation process. This study performed interviews in order to understand the economic issues related to carcass burial and redisposal. The internal data from local government and the assumption data from online sites were analyzed to evaluate the costs; the focus was on burial site construction. The results showed that the local government paid $4.7 and $10.9 per carcass for traditional burial and redisposal. The comparable costs shown online were $4.5. This study found that the standard operating procedures should be carried out to reduce environmental impact and avoid additional costs. We estimated that the cost could be reduced by the advance preparations of materials against the emergency situations such as catastrophe of epidemics. In addition, the innovative technology for the stabilization of carcasses should be established through a future study.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.285-292
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• 2004

Earth Anchor method as a supporting system is widely used in the large scale deep excavation of urban areas or slope excavation project. Considering the application frequency of that method and catastrophe of that method under unproper construction management, we can find out many problems relevant to the domestic design and construction management of earth anchor method. When we encounter the cases of rapid increments and various decrements in earth anchor axial forces, considering the characteristic of earth anchor method, it is an essential point to catch the reasons and to prepare countermeasures. This article introduces two actual monitoring examples based on the close analyses of measured data in a typical large scale deep excavation project and slope excavation project. One is a rapidly increasing case of earth anchor axial forces with the continuous advance of incremental deformation in a geological layer interface. And another is a decreasing case of earth anchor axial forces with the construction conditions. The effort of this article aims to improve and develop the technique of design and construction in the coming projects having similar ground condition and supporting method.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.3 s.33
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• pp.41-52
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• 2005

The high density of population and building; can cause catastrophe in urban areas when natural or artificial disasters break out. The aim of this paper is to assess comprehensive disasters risk of urban areas by Geospatial Information System. For this purpose, we classified disasters risk of urban areas into low categories: flood, fire, building-collapse, and shelter, and then determined factors for hazard risk assessment respectively. The results of hazard assessment can be applied to minimize the demage of disasters in establishing the urban management planning. For more systematic and professional approach the further research is need to consider more disaster assessment factors and join with related experts.

• Journal of Environmental Health Sciences
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• v.37 no.4
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• pp.237-249
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• 2011

The Chernobyl accident was a terrible catastrophe for humanity. Scientists are in concurrence about an increase of thyroid cancer incidence among children, but not among adults, because even areas less contaminated by radiation have also reported an increase in the incidence of thyroid cancer. In this case, the rise might be due to a screening effect. There is no convincing evidence that the incidence of leukemia and solid cancer has increased among the exposed populations, but it still remains a controversial issue. Additionally, apparent evidence of decreased fertility and increased hereditary effects have not been observed in the general population. WHO suggested 4,000 people could have died or may die in the future among emergency workers and residents of the most contaminated areas, while Greenpeace insists there will be 93,080 victims around the world. The radiation dose due to Chernobyl was mainly low, so if its health effects are to be found, more long-term and welldesigned research will be needed.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.877-887
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• 2015

Rapid development of cities with constant increasing load and deregulation in electricity market had forced the transmission lines to operate near their threshold capacity and can easily lead to voltage instability and caused system breakdown. To prevent such catastrophe from happening, accurate readings of voltage stability condition is required so that preventive equipment and operators can execute security procedures to restore system condition to normal. This paper introduced Enhanced Hybrid Particle Swarm Optimization algorithm to estimate the voltage stability condition which utilized Fast Voltage Stability Index (FVSI) to indicate how far or close is the power system network to the collapse point when the reactive load in the system increases because reactive load gives the highest impact to the stability of the system as it varies. Particle Swarm Optimization (PSO) had been combined with the ANN to form the Enhanced Hybrid PSO-ANN (EHPSO-ANN) algorithm that worked accurately as a prediction algorithm. The proposed algorithm reduced serious local minima convergence of ANN but also maintaining the fast convergence speed of PSO. The results show that the hybrid algorithm has greater prediction accuracy than those comparing algorithms. High generalization ability was found in the proposed algorithm.

• Geomechanics and Engineering
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• v.14 no.3
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• pp.241-246
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• 2018

The displacement monitoring data series reconstruction method was developed under equal water level effects based on displacement monitoring data of concrete dams. A dam displacement variation equation was set up under the action of temperature and aging factors by optimized analysis techniques and then the dam displacement hydraulic pressure components can be separated. Through the dynamic adjustment of temperature and aging effect factors, the aging component isolation method of dam displacement was developed. Utilizing the isolated dam displacement aging components, the dam stability model was established. Then, the dam stability criterion was put forward based on convergence and divergence of dam displacement aging components and catastrophe theory. The validity of the proposed method was finally verified combined with the case study.