• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.11 s.170
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• pp.2022-2032
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• 1999

In recent years, the subject of remaining life assessment has drawn considerable attention in the power generation industry. In power generation systems a variety of structural components, such as steam pipes, turbine rotors, and superheater headers, typically operate at high temperatures and high pressures. Thus a life prediction methodology accounting for fracture and rupture is increasingly needed for these components. For accurate failure assessment, in addition to the single parameter such as K or J-integral used in traditional fracture mechanics, the second parameter like T-stress describing the constraint is needed. The most critical defects in such structures are generally found in the form of semi-elliptical surface cracks in the welded piping-joints. In this work, selecting the structures of surface-cracked plate and straight pipe, we first perform line-spring finite element modeling, and accompanying elastic-plastic finite element analyses. We then present a framework for including constraint effects (T-stress effects) in the R6 failure assessment diagram approach for fracture assessment.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.359-366
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• 2009

CCS (Carbon Capture and Storage) is considered as the most promising interim solution to deal with the greenhouse gas such as $CO_2$ responsible for global warming. Even though carefully chosen geologic formations are known to contain stored gas for a long time period, there are potential risks of leakage. Up to now, applicable risk assessment procedures for the leakage of $CO_2$ are not available. This study presents a basis for risk analysis applicable to a complex geologic storage system. It starts with the classification of potential leakage pathways. Receptors and the leakage effect on them are identified and quantified. Then, a fault tree is constructed, which yields the minimum cut set (i.e., the most vulnerable leakage pathway) and quantifies the probability of the leakage risk through the cut set. The methodology will provide a tool for risk assessment in a CCS project. The outcomes of the assessment will not only ensure the safety of the CCS system but also offer a reliable and efficient monitoring plan.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.565-574
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• 2011

This paper aims to design a policy-assessment tool liking the Environmental Impact Assessment(EIA) and the Cost Benefit Analysis (CBA). As a step towards the incorporation of environmental and economic considerations, the approach used herein takes the form of integrating quantitative information on environmental benefits and costs associated with implementing the project into the existing framework of the EIA. Our case study is an project appraisal of a solar energy plant. It is confirmed that the technique is operational, however, there are certain limitations for a complete assessment. The difficulty mainly originated from the omission of important information from each step of the valuation process. Alternatively stated, some environmental services are not identified, nor quantified, and nor monetized in the process. More case studies are warranted in the future along with elaboration in methodology of techniques. In addition, the construction of a database on environmental values will be required to accumulate reliable and systematized data. These are the necessary conditions to improving quality in application of techniques as well as providing comprehensive and balanced information to decision makers.

• Korea Journal of Hospital Management
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• v.27 no.3
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• pp.39-49
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• 2022

Purposes: This study purposed to analyze the relationship between patient safety and patient-centerendess. Methodology: The comprehensive scores from patient safety assessment program and patient experience survey conducted by Health Insurance Review & Assessment Service were used as independent variables and dependent variables. This study analyzed the relationship between 4 patient safety-related areas(i.e. risk standardized readmission ratio, intensive care unit, preventive antibiotic, the drug evaluation) and 6 patient experience areas(i.e. nurse services, doctor services, medication & treatment, hospital environment, patient's right, overall experience) by using robust regression analysis. Findings: According to results, the score in 'patient's right' and 'risk standardized readmission ratio' areas were found to have a significant relationship, and 'overall experience' and the 'preventive antibiotic' areas. The ratio of senior beds and specialists was a general characteristics of hospitals that had a significant relationship on patient experience assessment. Practical Implication: The relationships between patient safety and patient experience assessment were varied depending on areas. Further study is needed to make clear the supposed relationship.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.155-156
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• 2023

This study aims to analyze the factors that cause differences in the evaluation results of the life cycle carbon emissions assessment of buildings in both Korea and China as part of the methodology research of building life cycle assessment for Chinese buildings to promote building life cycle assessment in China. Specifically, it examines the building LCA standards of Korea and the standard for building carbon emission calculation in China as mentioned in the green building certification systems of both countries. Based on the investigation of the two standards, the life cycle carbon emissions of the evaluation target building were evaluated using the building life cycle assessment methods of both countries, and the influencing factors that cause differences in the life cycle carbon emission assessment results of the two countries were analyzed.

• Review of Culture and Economy
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• v.20 no.1
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• pp.51-80
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• 2017

This study aims to analyze various issues and problems in the implementation process of cultural impact assessment in 2016. As a result of the analysis, it is found that the evaluation index of the cultural impact assessment is difficult to understand, and the referring data and materials in the evaluation planning phase in the process of the cultural impact assessment are deficient, and the evaluation planning is based on surveys rather than various methods. And there are some problems with evaluation scales and weighting, and they are focused on the evaluation itself rather than the feedback of the evaluation results. Therefore, this study suggests that, in the evaluation planning phase, the different methods of comparing the evaluation results according to the project execution, the project progress, and the completion time of the project should be adopted, and the project manager and the evaluation group participate developing the evaluation indicators together, and methodology for identifying causal relationship such as system dynamics will be adopted. In the stage of evaluation, it is necessary to introduce various methodology such as diverse residents participation, abundant case study, application of quantitative methodology, and the utilization of expert evaluation teams. In the evaluation feedback stage, it is necessary to provide thorough consulting based on the evaluation results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2305-2311
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• 2002

The pressure tube is a major component of the CANDU reactor, which supports nuclear fuel bundle and heavy water coolant. Pressure tubes are installed horizontally inside the reactor and only selected samples are periodically examined during in-service inspection. In this respect, a probabilistic safety assessment method is more appropriate fur the assessment of overall pressure tube safety. The failure behavior of CANDU pressure tubes, however, is governed by delayed hydride cracking which is the major difference from pipings and reactor pressure vessels. Since the delayed hydride cracking has more widely distributed governing parameters, it is impossible to apply a general PFM methodology directly. In this paper, a PFM methodology for the safety assessment of CANDU pressure tubes is introduced by applying Monte Carlo simulation in determining failure probability Initial hydrogen concentration, flaw shape and depth, axial and radial crack growth rate and fracture toughness were considered as probabilistic variables. Parametric study has been done under the base of pressure tube dimension and hydride precipitation temperature in calculating failure probability. Unstable fracture and plastic collapse are used for the failure assessment. The estimated failure probability showed about three-order difference with changing dimensions of pressure tube.

• The Korean Journal of Community Living Science
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• v.15 no.2
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• pp.167-177
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• 2004

The number of foodborne salmonellosis was estimated by using microbial risk assessment(MRA) methodology and the possibility of application was studied through comparison with previous results. The contamination levels of Salmonella sp. were estimated by using published domestic studies(1997∼2000) and monitoring data (1999∼2001) from food-safety related institutes. Data on food consumption came from the 2001 National Health and Nutrition Survey, and dose-response models from studies in other countries. Simulation results showed that there were 753,368 cases of salmonellosis in Korea in 1 year, which is about 115 times that reported in previous years and lower than the WHO's estimation increase. From these results, microbial risk assessment is likely to be available for estimation of the number of foodborne illnesses and determination of the order of priority in food-safety management. Butthe verification methods are not established and most of the data on contamination levels of foodborne bacteria, food consumption, and dose-response relationships have not been established. In addition, the actual conditions of circulation, storage and cooking must be studied further.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.95-111
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• 2012

The service quality survey for the customers of Gwangyang container port has been done since 2005. It has been difficult to compare annual levels or rival ports because the calculation of weights among service dimensions that is the most important procedure of the assessment systems did not be founded. In particular, the calculation results by the Analytical Hierarchy Process that specializes in estimating the weights were very unstable and not comparable because they were fluctuated annually more than 90% for the specific item. The objective of this study is to support the establishment for new assessment system of service quality with cost- and time-effective tools at Gwangyang port. The confirmatory factor analysis methodology applied to 2007-2009 survey data from the customers of Gwangyang port can estimate ex-post weights to measure annually the stable service quality. The proposed methodology allows us to build the assessment system of more scientific and accurate service quality while reducing the survey items. By this study, a port company can measure accurately the quality of service and improve its competitiveness through being compared to previous periods and leading companies.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.122-138
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• 2008

A pixel-based approach to urban quality of life assessment can be regarded as a spatial decision problem under the condition of complexity because it searches the urban space for evidence of hot spots of quality of life based on multiple and differentially weighted evaluation criteria. Such an assessment involves inappropriate scaling of several incommensurate criteria, much unstructured subjectivity in the decision maker's judgment, and the large data handling in a raster GIS environment. There is a need for identifying alternative approaches to tackle the ill-structured problem in urban quality of life assessment. In this context, this research proposes and implements a spatial multicriteria analysis approach to evaluate urban quality of life in a raster GIS environment. The implementation of this methodology is illustrated with a case study of the Atlanta metropolitan area. Results indicate that the proposed methodology may provide an alternative approach for evaluating the quality of life in an urban environment.