• Tunnel and Underground Space
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• v.27 no.2
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• pp.89-99
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• 2017

For a successful performance of Carbon Capture Sequestration (CCS) projects, appropriate injection conditions should be designed to be optimized for site specific geological conditions. In this study, we built a simple 2-dimensional analysis model, based on the geology of Jang-gi basin which is one of the potential sites of domestic CCS projects. We evaluated the impact of initial stress conditions and injection rate through coupled TOUGH-FLAC simulator. From the preliminary analysis, we constructed risk scenarios with the higher potential of shear slip and performed scenario analysis. Our analysis showed that normal stress regime produced the highest potential of shear slip and stepwise increasing injection rate scenario resulted in much larger pore pressure build up and consequent higher potential of the shear slip, which was evaluated using a mobilized friction coefficient.

• Journal of the Society of Disaster Information
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• v.11 no.1
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• pp.23-34
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• 2015

This Study analyzed heavy snow properties according to the area that was based by winter weather properties and the damage data by the heavy snow among each local government of Chungcheongbuk-do. The result of analysis, Jecheon-si and Boeun-gun are represented the highest dangerous regions by potential degree of risk by average amount of snowfall for 35 years. But, the potential degree of risk by maximum amount of snowfall for 35 years is different with it. Cheongju-si and Youngdong-gun, Goesan-gun, Boeun-gun are represented the highest dangerous regions. Examining the frequency of regions with potential danger factors according to the characteristics of heavy snowfall, Boeun-gun and Jecheon-si, Goesan-gun, Youngdong-gun, Cheongju-si is derived the highest dangerous regions in Chungcheongbuk-do.

• Journal of the Korean GEO-environmental Society
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• v.19 no.10
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• pp.13-19
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• 2018

Following the 2016 Gyeongju earthquake, the Pohang Earthquake occurred in 2017, and the south-east region in Korea is under the threat of an earthquake. Especially, in the Pohang Earthquake, the liquefaction phenomenon occurred in the sedimentation area of the coast, and preparation of countermeasures is very important. The soil liquefaction can affect the underground facilities directly as well as various structures on the ground. Therefore, it is necessary to identify the liquefaction risk of facilities and the structures against the possible earthquakes and to prepare countermeasures to minimize them. In this study, we investigated the seismic liquefaction risk about the electric power utility tunnels in the southeast area where the earthquake occurred in Korea recently. In the analysis of seismic liquefaction risk, the earthquake with return period 1000 years and liquefaction potential index are used. The liquefaction risk analysis was conducted in two stages. In the first stage, the liquefaction risk was analyzed by calculating the liquefaction potential index using the ground survey data of the location of electric power utility tunnels in the southeast region. At that time, the seismic amplification in soil layer was considered by soil amplification factor according to the soil classification. In the second stage, the liquefaction risk analysis based on the site response analyses inputted 3 earthquake records were performed for the locations determined to be dangerous from the first step analysis, and the final liquefaction potential index was recalculated. In the analysis, the site investigation data were used from the National Geotechnical Information DB Center. Finally, it can be found that the proposed two stage assessments for liquefaction risk that the macro assessment of liquefaction risk for the underground facilities including the electric power utility tunnel in Korea is carried out at the first stage, and the second risk assessment is performed again with site response analysis for the dangerous regions of the first stage assessment is reasonable and effective.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.7
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• pp.3071-3074
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• 2014

Background: To investigate the related risk factors of postoperative nosocomial pneumonia (POP) in patients withI-IIIa lung cancer. Methods: Medical records of 511 patients who underwent resection for lung cancer between January 2012 to December 2012 were retrospectively reviewed. Risk factors of postoperative pneumonia were identified and evaluated by univariate and multivariate analyses. Results: The incidence of postoperative pneumonia in these lung cancer patients was 2.9% (15 cases). Compared with 496 patients who had no pneumonia infection after operation, older age (>60), histopathological type of squamous cell carcinoma and longer surgery time (>3h) were significant risk factors by univariate analysis. Other potential risk factors such as alcohol consumption, history of smoking, hypersensitivity, hypertension, diabetes mellitus and so on were not showed such significance in this study. Further, the multivariate analysis revealed that old age (>60 years) (OR 5.813, p=0.018) and histopathological type of squamous cell carcinoma (OR 5.831, p<0.001) were also statistically significant independent risk factors for postoperative pneumonia. Conclusions: This study demonstrated that being old aged (>60 years) and having squamous cell carcinoma histopathological type might be important factors in determining the risk of postoperative pneumonia in lung cancer patients after surgery.

• Journal of Radiation Protection and Research
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• v.35 no.1
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• pp.6-11
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• 2010

Embodying the safety of radioactive waste disposal requires the relevant safety criteria and the corresponding stylized methods to demonstrate its compliance with the criteria. This paper proposes a conceptual model of risk-based safety evaluation for integrating complex potential radiation exposure situations in radioactive waste disposal. For demonstrating compliance with a risk constraint, the approach deals with important exposure scenarios from the viewpoint of the receptor to estimate the resulting risk. For respective exposure situations, it considers the occurrence probabilities of the relevant exposure scenarios as their probability of giving rise to doses to estimate the total risk to a representative person by aggregating the respective risks. In this model, an exposure scenario is simply constructed with three components:radionuclide release, radionuclide migration and environment contamination, and interaction between the contaminated media and the receptor. A set of exposure scenarios and the representative person are established from reasonable combinations of the components, based on a balance of their occurrence probabilities and the consequences. In addition, the probability of an exposure scenario is estimated on the assumption that the initiating external factors influence release mechanisms and transport pathways, and its effect on the interaction between the environment and the receptor may be covered in terms of the representative person. This integrated approach enables a systematic risk assessment for complex exposure situations of radioactive waste disposal and facilitates the evaluation of compliance with risk constraints.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.381-393
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• 2015

This study is carried out in order to propose a drought risk assessment methodology. This methodology is required to deal with practical questions that a variety of stakeholder often raise in the course of discussions on mitigation measures. With a focus on the socioeconomic aspect of drought, more particularly, residents' hardship from water scarcity, it suggests basic concepts and a system of methods in order to assess hazard, exposure, vulnerability and risk. The case study shows a considerable possibility of the methodology in evaluating potential levels of damages in a certain area, in identifying the boundary of districts where risk is disproportionately concentrated, and also in understanding the underlying risk factors of those districts. The authors think that the proposed methodology is able to offer risk information in terms of socioeconomic damages, and therefore contribute to reducing information gaps that policy-makers are currently encountered with.

• The Korean journal of helicobacter and upper gastrointestinal research
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• v.18 no.4
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• pp.225-230
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• 2018

Upper gastrointestinal (GI) bleeding (UGIB) is the most common GI emergency, and it is associated with significant morbidity and mortality. Early identification of low-risk patients suitable for outpatient management has the potential to reduce unnecessary costs, and prompt triage of high-risk patients could allow appropriate intervention and minimize morbidity and mortality. Several risk-scoring systems have been developed to predict the outcomes of UGIB. As each scoring system measures different primary outcome variables, appropriate risk scores must be implemented in clinical practice. The Glasgow-Blatchford score (GBS) should be used to predict the need for interventions such as blood transfusion or endoscopic or surgical treatment. Patients with GBS ${\leq}1$ have a low likelihood of adverse outcomes and can be considered for early discharge. The Rockall score was externally validated and is widely used for prediction of mortality. The recently developed AIMS65 score is easy to calculate and was proposed to predict in-hospital mortality. The Forrest classification is based on endoscopic findings and can be used to stratify patients into high- and low-risk categories in terms of rebleeding and thus is useful in predicting the need for endoscopic hemostasis. Early risk stratification is critical in the management of UGIB and may improve patient outcome and reduce unnecessary health care costs through standardization of care.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.77-84
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• 2018

Report documents of industrial and occupational accidents have continuously been accumulated in private and public institutes. Amongst others, information on narrative-texts of accidents such as accident processes and risk factors contained in disaster report documents is gaining the useful value for accident analysis. Despite this increasingly potential value of analysis of text information, scientific and algorithmic text analytics for safety management has not been carried out yet. Thus, this study aims to develop data processing and visualization techniques that provide a systematic and structural view of text information contained in a disaster report document so that safety managers can effectively analyze accident risk factors. To this end, the risk factor map using text mining and self-organizing map is developed. Text mining is firstly used to extract risk keywords from disaster report documents and then, the Self-Organizing Map (SOM) algorithm is conducted to visualize the risk factor map based on the similarity of disaster report documents. As a result, it is expected that fruitful text information buried in a myriad of disaster report documents is analyzed, providing risk factors to safety managers.

• Journal of the FoodService Safety
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• v.3 no.2
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• pp.49-58
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• 2022

The objectives of this study were to investigate the behavior characteristics of pathogenic E. coli, Salmonella Typhimurium, Campylobacter jejuni, and Listeria monocytogenes in various kinds of meat (beef, chicken, and pork) and to compare their risk using FDA-iRISK. The growth of S. Typhimurium in chicken and pathogenic E. coli in pork and beef was well supported and posed a high risk. A similar trend was observed in the risk comparison results using the iRISK. When comparing total disability adjusted life years (DALY) per year based on the kinds of meat, chicken was the highest (88.2), followed by pork (58.5) and beef for "yukhoe" (18.8). When comparing scenarios grouped by bacteria, The highest total DALYs per year was observed with pathogenic E. coli (121), followed by S. Typhimurium (44.8) and L. monocytogenes (1.67E-³). These results indicate that the risk of combining meat and foodborne pathogens varies under the same distribution environment. Thus, strict management and supervision are required to store and deliver raw meat to prevent cross-contamination among the raw meats at the processing plant and retail market.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.155-163
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• 2014

Total concentration and chemical speciation of trace metals (Cu, Pb, Zn, Cd, and Ni) were determined to evaluate pollution level and potential ecological risk in surface sediments of the Masan Bay. The results showed that the trace metal concentrations, except for Ni, were high in the inner Masan Bay. Based on the chemical speciation of metals in sediments, the percentage of total concentrations of Cd and Pb in non-residual fraction was 92% and 88%, respectively, indicating that these metals originated mainly from anthropogenic sources. However, Ni (70%) was dominant in residual fraction. Pollution load index (PLI) and ecological risk index (ERI) values in the inner bay indicate the presence of anthropogenic pollution and considerable-moderate ecological risk, respectively. Ecological index (Ei) value for Cd was high at most stations in the Masan Bay, and Cd content was the highest in acid soluble fraction, which presents the highest ecological risk. The results obtained in this study indicate that Cd presents a high potential ecological risk to benthic biota in the Masan Bay.