• Proceedings of the Korean Association for Survey Research Conference
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• 2002.11a
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• pp.111-127
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• 2002

As the utilization of official statistics has been recently increased, the necessity of objective quality assessment also has been increased. Since mean square error(MSE) and response rate, which have been considered as representative quality indicators in the past, may have the limits of use, it has been demanded to develop new quality indicators which are able to reflect the various requirements of users. In this paper, regarding sample surveys conducted by governmental agencies, the flow of procedures in statistics production is analyzed using input-output of each procedure. As the result, how to identify and develop quality indicators for each procedure is discussed, with some instances of indicators. Finally, the quality index using the results of quality assessment would be calculated based on a weighting method by the size of deviation of statistical measures.

• Nuclear Engineering and Technology
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• v.31 no.3
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• pp.267-275
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• 1999

This paper deals with the industrial problem of thermal striping damage on the French prototype fast breeder reactor, Phenix and it was studied in coordination with the research program of IAEA. The thermomechanical and fracture mechanics evaluation procedure of thermal striping damage on the tee-junction of the secondary piping using Green's function method and standard FEM is presented. The thermohydraulic(T/H) loading condition used in the present analysis is the random type thermal loads computed by T/H analysis on the turbulent mixing of the two flows with different temperatures. The thermomechanical fatigue damage was evaluated according to ASME code section 111 subsection NH. The results of the fatigue analysis showed that fatigue failure would occur at the welded joint within 90,000 hours of operation. The assessment for the fracture behavior of the welded joint showed that the crack would be initiated at an early stage in the operation. It took 42,698.9 hours for the crack to propagate up to 5 mm along the thickness direction. After then, however, the instability analysis, using tearing modulus, showed that the crack would be arrested, which was in agreement with the actual observation of the crack. An efficient analysis procedure using Green's function approach for the crack propagation problem under random type load was proposed in this study. The analysis results showed good agreement with those of the practical observations.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.5
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• pp.404-413
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• 2011

It is important to assess and improve the warship survivability for the weapon threats which have a critical effect on warship. The survivability of the warship is defined as the capability of a warship to avoid or withstand a man-made hostile environment. The survivability of the warship consists of three categories (Susceptibility, Vulnerability and Recoverability). Firstly, the susceptibility is defined as the inability of a warship to avoid radars, guns, missiles and etc. Secondly, the vulnerability is defined as the inability of a warship to withstand the man-made hostile environment. Finally, the recoverability is defined as the ability of a warship to recover the damaged components and systems. Among them, this paper has described the vulnerability assessment for the hypothetical system which is composed of critical components. Also, the procedure which is suggested to calculate the vulnerable probability of the damaged warship is based on the Vulnerable Area Method.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.3
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• pp.141-148
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• 2020

For the important safety system, two or more units of identical equipment or redundant components with similar function were installed to prevent abnormal failure. If the failure probability of such equipment is independent, this redundancy could increase the system safety remarkably. However, if the failure of each component is highly correlated by installing in a structure or experiencing an earthquake event, the expected redundancy effect will decrease. Therefore, the seismic correlation of the equipment should be evaluated quantitatively for the seismic probabilistic safety assessment. The correlation effect can be explained in the procedure of constructing fragility curves. In this study, several methodologies to quantify the seismic correlation in the failure probability calculation for multiple components were reviewed and two possible ways considering the realistic situation were selected. Simple examples were tested to check the applicability of these methods. The conversion method between these two methods was suggested to render the evaluation using the advantages of each method possible.

• The Journal of the Korean life insurance medical association
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• v.26
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• pp.31-39
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• 2007

Background and main issue: In the Korean insurance market, an outstanding issue is the decrease of margin of risk ratio. This affects the solvency and profitability of insurance companies. Insurance medicine, which has been developed in Western countries, is so-called medical risk selection or medical underwriting. Medical risk selection is based on clinical follow-up study and mortality analysis methodology. Unfortunately, there have been few clinical follow-up studies, and no intercompany disease analysis system is available in the Korean insurance market. In practice, we use underwriting guidelines, which were developed by some global reinsurance companies. However, these guidelines were developed under clinical follow-up studies performed abroad. So, we cannot rule out underestimation of excess mortality factors such as mortality ratio, excess death rate, and life expectancy. It is necessary to perform medical assessment in claims administration. Comparing the insured's statement by medical records with products' benefit according to this procedure, we can make sound claim decisions and participate in the role of sound underwriting. We can call this scientific procedure as the verification of medical claims review. Another area of medical claims review is medical counsel for claims staff. Result: There is another insurance medicine in addition to medical risk selection. Independent medical assessment by medical records of insured is medical claims review. Medical claims review is composed of verification and counsel.

• Korean Journal of Health Education and Promotion
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• v.20 no.1
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• pp.1-17
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• 2003

This study purports to assess the process quality of health promotion programs at public health centers. The sample used in this study consisted of 242 public health centers in South Korea. Data was collected with self-administered questionnaires between September. 3rd to September. 23rd in 2002. The 95 returned questionnaires were analyzed by SPSS 11.0 version. The major findings are as follows; There is a need to improve (1) a procedure for reviewing and analyzing strategic planning, (2) the quality of the staff in charge of program management, (3) the function of planning and training for monitoring and evaluation, (4) the ability of program managers in advising and consulting with clients, and (5) a procedure for organizing resources and information. In conclusion, in order to improve the process quality of health promotion programs at public health centers, integrated support from various institutions such as public health centers, community, regional and national health authorities and administrative departments is required.

• Industrial Engineering and Management Systems
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• v.11 no.1
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• pp.54-69
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• 2012

Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

• Advances in concrete construction
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• v.1 no.1
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• pp.85-102
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• 2013

Prior concrete strength distributions can be updated by using direct information from test results as well as by taking into account indirect information due to conformity control. Due to the filtering effect of conformity control, the distribution of the material property in the accepted inspected lots will have lower fraction defectives in comparison to the distribution of the entire production (before or without inspection). A methodology is presented to quantify this influence in a Bayesian framework based on prior knowledge with respect to the hyperparameters of concrete strength distributions. An algorithm is presented in order to update prior distributions through numerical integration, taking into account the operating characteristic of the applied conformity criteria, calculated based on Monte Carlo simulations. Different examples are given to derive suitable hyperparameters for incoming strength distributions of concrete offered for conformity assessment, using updated available prior information, maximum-likelihood estimators or a bootstrap procedure. Furthermore, the updating procedure based on direct as well as indirect information obtained by conformity assessment is illustrated and used to quantify the filtering effect of conformity criteria on concrete strength distributions in case of a specific set of conformity criteria.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.1
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• pp.28-37
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• 2022

Along with the remarkable advances in GNSS technology, SBAS further enhances the accuracy and integrity of GNSS location information and derives improvement in the safety and efficiency of air traffic management from reducing GNSS location errors, induced by passing through the ionosphere and atmosphere, to less than three meters. In this regard, ICAO specifies the standards of SBAS signals and recommends every party to phase in by 2025; and it is foreseeable that SBAS APV-I and CAT-I will be provided in South Korea by its undertaking the development of KASS, a Korean SBAS. The purpose of the study is to design SBAS APV-I procedure on the basis of the runway 15L of Incheon International Airport and conduct obstacle assessment according to PAN-OPS Doc. 8168, focusing on the usability and usefulness of SBAS APV-I. The results show that SBAS APV-I will provide better decision height compared to other PBN RNP approach procedures such as LNAV and Baro-VNAV at the Incheon International Airport.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2915-2923
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• 2022

There is an increasing interest in passive safety systems to minimize the need for operator intervention or external power sources in nuclear power plants. Because a passive system has a weak driving force, there is greater uncertainty in the performance compared with an active system. In previous studies, several methods have been suggested to evaluate passive system reliability, and many of them estimated the failure probability using thermal-hydraulic analyses and the Monte Carlo method. However, if the functional failure of a passive system is rare, it is difficult to estimate the failure probability using conventional methods owing to their high computational time. In this paper, a procedure for the application of the Chernoff bound to the evaluation of passive system reliability is proposed. A feasibility study of the procedure was conducted on a passive decay heat removal system of a micro modular reactor in its conceptual design phase, and it was demonstrated that the passive system reliability can be evaluated without performing a large number of thermal-hydraulic analyses or Monte Carlo simulations when the system has a small failure probability. Accordingly, the advantages and constraints of applying the Chernoff bound for passive system reliability evaluation are discussed in this paper.