• Earthquakes and Structures
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• v.14 no.5
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• pp.437-447
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• 2018

Computational cost is one of the major obstacles for detailed risk analysis of structures. This paper puts forward a methodology for efficient probabilistic seismic loss assessment of structures using the Endurance Time (ET) analysis and the first-order reliability method (FORM). The ET analysis efficiently yields the structural responses for a continuous range of intensities through a single response-history analysis. Taking advantage of this property of ET, FORM is employed to estimate the annual rate of exceedance for the loss components. The proposed approach is an amalgamation of two analysis approaches, ET and FORM, that significantly lower the computational costs. This makes it possible to evaluate the seismic risk of complex systems. The probability distribution of losses due to the structural and non-structural damage as well as injuries and fatalities of a prototype structure are estimated using the proposed methodology. This methodology is an alternative to the prevalent risk analysis framework of the total probability theorem. Hence, the risk estimates of the proposed approach are compared with those from the total probability theorem as a benchmark. The results indicate a satisfactory agreement between the two methods while a significantly lower computational demand for the proposed approach.

• Earthquakes and Structures
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• v.11 no.4
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• pp.583-607
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• 2016

One of the main applications of seismic risk assessment is that an specific design could be selected for a bridge from different alternatives by considering damage losses alongside primary construction costs. Therefore, in this paper, the focus is on selecting the shape of pylon, which is a changeable component in the design of a cable-stayed bridge, as a double criterion decision-making problem. Different shapes of pylons include H, A, Y, and diamond shape, and the two criterion are construction costs and probable earthquake losses. In this research, decision-making is performed by using developed seismic risk assessment process as a powerful method. Considering the existing uncertainties in seismic risk assessment process, the combined incremental dynamic analysis (IDA) and uniform design (UD) based fragility assessment method is proposed, in which the UD method is utilized to provide the logical capacity models of the structure, and the IDA method is employed to give the probabilistic seismic demand model of structure. Using the aforementioned models and by defining damage states, the fragility curves of the bridge system are obtained for the different pylon shapes usage. Finally, by combining the fragility curves with damage losses and implementing the proposed cost-loss-benefit (CLB) method, the seismic risk assessment process is developed with financial-comparative approach. Thus, the optimal shape of the pylon can be determined using double criterion decision-making. The final results of decision-making study indicate that the optimal pylon shapes for the studied span of cable-stayed bridge are, respectively, H shape, diamond shape, Y shape, and A shape.

• Journal of Chest Surgery
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• v.28 no.11
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• pp.973-976
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• 1995

The assessment method of human body composion by bioelectrical impedance is very simple, safe, rapid and noninvasive. Based on prediction formulas for total body water from bioelectrical impedance, the observed weight loss should be associated with an increase in impedance. However in edematous patients for dialysis, the calculated total body water loss as calculated from impedance were overestimated and significantly higher than the weight loss after dialysis. So determination of impedance were made in 50 edematous patients before, during and after dialysis. Mean weight loss, which was assumed to be only loss of water was 1719$\pm$ 866 gr and mean impedance change was 71.0 $\pm$ 23.0 Ohm under 50kHz. Body weight loss was highly correlated [r>0.81 with the increase in body impedance under variable frequencies[1, 10, 20, 30, 40, 50 kHz . But there were no differences between frequences. In conclusion, clinical application of bioelectrical impedance method is useful for individual edematous patients with new correlation equation[Y=230+26.8X, X;Impedance change, Y;Calculated total body water loss .

• Journal of Environmental Impact Assessment
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• v.17 no.4
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• pp.243-253
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• 2008

The purpose of this study was to simulate the reduction effect of soil loss in the Yongdam reservoir watershed using SWAT model. To evaluate accuracy for flow and sediment yield of SWAT model, calibration was performed for the period from Jan. 2002 to Dec. 2003, and the verification for Jan. 2005 to Dec. 2005. The calibration and the verification were carried out using data observed at the Cheoncheon gaging station. The $R^2$ and EI values in terms of a flow were 0.8 and 0.78 respectively for calibration, whereas they for verification were 0.88 and 0.86 respectively. In terms of a sediment yield, they were 0.7 and 0.48 respectively for calibration, whereas for verification were 0.64 and 0.54 respectively. As a results from model simulation, annual mean soil loss rates in terms of forest, paddy and upland were 0.02 ton/ha/yr, 0.15 ton/ha/yr and 7.58 ton/ha/yr, respectively. The results show that the land use type of a upland has more significant impact on a total soil loss as well as a sediment yield than other types of land use. The sediment delivery ratio was determined to be about 0.35. In this study 2 land cover change scenarios for upland area were considered. These scenarios were used an input to SWAT model in order to evaluate their impact on soil loss and sediment delivery. The results show that a reduction of the upland area would reduce the soil loss and sediment yield.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_1
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• pp.439-446
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• 2013

This paper is about assessment of soil loss in irrigation reservoir based on GIS. Natural disaster caused by soil loss whose natural incidence has been rapidly reduced due to successful tree planting campaign shows high potential risk, since the latest localized heavy rain resulted from extreme weather event and artificial land development acts as direct factors for land disaster. To prevent it, various techniques and technologies have been used to predict effect of soil loss. However, reliability of techniques and technologies to predict its effect precisely is relatively low so far because the natural disaster by soil loss is taken place by complicated interaction between possible factors and direct factors. Geospatial approach is essential to examine these interactions. In this regard, this study will provide detailed plan to improve prediction reliability for soil loss of irrigation reservoir, using GIS that has Hydrologic -Topographical parameter and digital map as its input parameters.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1419-1424
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• 2004

Railway safety is based on a risk analysis and safety assessment for the whole railway system as human, train, electric, signaling, operation, maintenance and etc. Therefore in this study, after investigating the accidents happened in electric railway on Choongang line for 5 years, from '97 to '01, a Data-Base was made through a cause and result analysis. In consideration of economic loss and human resources damage, a risk assessment for electric railway was also performed.

• Journal of Korea Association of Health Promotion
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• v.4 no.1
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• pp.1-11
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• 2006

"본 논문은 대한외과학회지 2006년 제70권제1호에 실렸던 논문으로 대한외과학회 편집위원회 승인을 득하고 본 협회지에 게재함. Purpose: Malnutrition has been frequently reported for patients on their admission to the hospital and it has been associated with an increase in morbidity, mortality and the length of the hospital stay. Although a number of screening tools have been developed to identify those patients at risk for malnutrition, there is no' gold standard' for defining malnutrition and the malnourished patients remain largely unrecognized. The aim of this study is to evaluate the efficacy of a nutritional screening tool for use in Dankook University Hospital. Methods Nutritional evaluation was performed for 53 patients who were admitted to the department of surgery and internal medicine between October and December 2004. The screening tool was completed by the ward nurse and the nutritional support team nurse on the same patients within24 hours of admission. The nutritional support team nurse performed the full assessment. The screening sheet included 4 questions regarding body mass index, recent unintentional weight loss, food intake and disease severity. Each answer was scored and a total of 5 was tested as the criterion fey malnutrition. The full assessment included current body weight, recent weight loss, triceps skinfold thickness, mid-arm muscle circumference, serum albumin)in and total lymphocyte count. Malnutrition was defined by 3 or more values below the reference values. The reliability of the screening tool was assessed using kappa statistic. Sensitivity, specificity and accuracy were calculated to evaluate the validity of the screening tool. The receiver operating characteristic(ROC) curve was drawn to choose a cutoff valve that maximizes sensitivity and specificity. Results' The level of agreement between the ward nurse and the NST nurse was good for BMI and food intake and moderate for weight loss and disease severity. The full assessment identified7 patients(13.2%) as malnourished. The screening sheet had a sensitivity of 86% and a specificity of 80%. According to the ROC curve, a score of 5 points provided the best validity. Conclusion The nutritional screening tool is reliable when completed by different observers and it is valid for nutritional assessment.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2004.11a
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• pp.60-60
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• 2004

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.3
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• pp.43-55
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• 2023

The railway project is an essential green transportation tool that is considered suitable for the domestic and foreign policy direction of carbon neutrality, but there are some limitations, such as damaging important carbon absorption sources during construction. This study analyzed the environmental impact assessment related to carbon absorption sources of greenhouse gas evaluation items conducted during the railway project, and limitations and implications were derived. The analysis of environmental impact assessment guidelines related to railway projects and carbon absorption sources dealt with prediction and reduction methods related to carbon absorption sources, but guidelines, including environmentally friendly railway construction guidelines, lacked descriptions. Since the greenhouse gas environmental impact assessment, 83 railway project environmental impact assessments have been reviewed, but in some cases, carbon absorption-related predictions have not been implemented, or carbon absorption-related reduction measures have been insufficient. In addition, there were cases where there was a limit to calculating emissions and reduction or where the reduction value was insignificant compared to emissions. In order to supplement the environmental impact assessment in the field of carbon absorption sources related to railway construction projects, alternatives such as quantitative emission and low reduction calculation, review of the no net loss system using the total environmental resource system, and linkage with climate change impact assessment are needed.

• Geomechanics and Engineering
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• v.35 no.6
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• pp.581-591
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• 2023

North Anatolian Fault Zone is tectonically active with recent earthquakes (Mw7.6 1999-Kocaeli and Mw7.2 1999-Düzce earthquakes) and it passes through Marmara region, which is highly industrialized, densely populated and economically important part of Turkey. Many power plants, located in Marmara region, are exposed to high seismic hazard. In this study, open source OpenQuake software has been used for the probabilistic earthquake hazard analysis of Marmara region and risk assessment for the specified energy facility. The SHARE project seismic zonation model has been used in the analysis with the regional sources, NGA GMPEs and site model logic trees. The earthquake hazard results have been compared with the former and existing earthquake resistant design regulations in Turkey, TSC 2007 and TBSCD 2018. In the scope of the study, the seismic hazard assessment for a typical natural gas combined cycle power plant located in Marmara region has been achieved. The seismic risk assessment has been accomplished for a typical control building located in the power plant using obtained seismic hazard results. The structural and non-structural fragility functions and a consequence model have been used in the seismic risk assessment. Based on the seismic hazard level with a 2% probability of exceedance in 50 years, considered for especially these type of critical structures, the ratios of structural and non-structural loss to the total building cost were obtained as 8.8% and 45.7%, respectively. The results of the study enable the practical seismic risk assessment of the critical facility located on different regions.