• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.2
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• pp.81-86
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• 2014

In this paper, we states the verification and validation methodology for the modular system of A-SMGCS which defined in the ICAO Manual on Advanced Surface Movement Guidance and Control Systems. Such systems aim to maintain the declared surface movement rate under all weather conditions while maintaining the required level of safety. With the complete concept of an A-SMGCS, air traffic controllers, vehicle drivers, flight crews, and are assisted with surface operations in terms of surveillance, control, routing/planning and guidance tasks. A-SMGCS verification and validation for the development of Real Time Simulation, shadow mode trials, operational trials are conducted through three methods. In this study, the characteristics and the need for such a verification method was examined.

• The Journal of the Korea Contents Association
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• v.5 no.2
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• pp.95-105
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• 2005

As a research on PKI is being very popular, the study relating to certificate status validation is being grown with aim to reduce an overhead of the protocol and to provide an efficient operation. The OCSP of the standard protocol related to the study enables applications to determine the revocation state of an identified certificate. However, the OCSP server can not service millions of certificate status validation requests from clients in a second on E-commerce because of the computational time for signature and verification. So, we propose the Real-time Certificate Status Validation Protocol(RCSVP) that has smaller computational time than OCSP. RCSVP server reduce the computational time of certificate status validation using hash function and common secret value. Also RCSVP client does not need the computational time of certificate verification to acquire the public key from an identified certificate. Therefore, the proposed protocol enables server to response millions of certificate status validation requests from clients in a second on E-commerce.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1857-1863
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• 2013

Most of biomaterials come in direct contact with the body, making standardized methods of evaluation and validation of biocompatibility an important aspect to biomaterial development. However, biomaterial validation guidelines have not been fully established, until now. This study was to compare the in vitro behavior of osteoblasts cultured on nanomaterial $TiO_2$ surfaces to osteoblast behavior on culture plates. Comparisons were also made to cells grown in conditioned media (CM) that creates an environment similar to the in vivo environment. Comparisons were made between the different growth conditions for osteoblast adhesion, proliferation, differentiation, and functionality. We found that the in vivo-like system of growing cells in concentrated CM provided a good validation method for biomaterial development and in vivo implant therapy. The $TiO_2$ materials were biocompatible, showing similar behavior to that observed in vivo. This study provided valuable information that would aid in the creation of guidelines into standardization and evaluation of biocompatibility in $TiO_2$ biomaterials.

• Journal of Korean Academy of Nursing
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• v.45 no.1
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• pp.129-138
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• 2015

Purpose: The purpose of this study was to report the instrument modification and validation processes to make existing health belief model scales culturally appropriate for Korean Americans (KAs) regarding colorectal cancer (CRC) screening utilization. Methods: Instrument translation, individual interviews using cognitive interviewing, and expert reviews were conducted during the instrument modification phase, and a pilot test and a cross-sectional survey were conducted during the instrument validation phase. Data analyses of the cross-sectional survey included internal consistency and construct validity using exploratory and confirmatory factor analysis. Results: The main issues identified during the instrument modification phase were (a) cultural and linguistic translation issues and (b) newly developed items reflecting Korean cultural barriers. Cross-sectional survey analyses during the instrument validation phase revealed that all scales demonstrate good internal consistency reliability (Cronbach's alpha=.72~.88). Exploratory factor analysis showed that susceptibility and severity loaded on the same factor, which may indicate a threat variable. Items with low factor loadings in the confirmatory factor analysis may relate to (a) lack of knowledge about fecal occult blood testing and (b) multiple dimensions of the subscales. Conclusion: Methodological, sequential processes of instrument modification and validation, including translation, individual interviews, expert reviews, pilot testing and a cross-sectional survey, were provided in this study. The findings indicate that existing instruments need to be examined for CRC screening research involving KAs.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.831-842
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• 2022

Purpose: This study carried out the Quality by Design (QbD)6σ process to verify the effectiveness and equivalence of the finished D-antigen quantitative test method, and compared the OFAT-based method validation and test result acceptance criteria with the Analytical Quality by Design (AQbD)-based method validation and test method. This is a study on how to reduce the risk of delay in permit change by increasing the reliability of permit data in the existing method by statistically analyzing the results. Methods: With the QbD6σ process, the effectiveness and equivalence of the D-antigen quantitative test method were verified with the data of the existing test method and the new test method. Results: Method validation tests are performed based on AQbD. Critical Method Parameters are identified through risk assessment, and single/combined actions are verified by designing and performing tests for Critical Method Parameters (analysis of variance, full factorial design method). Method validation can be effectively accomplished with the QbD6σ process. Conclusion: The use of QbD6σ can be used to achieve satisfactory results for both pharmaceutical companies and regulators by using appropriate statistical analytical methods for method validation as required by regulatory agencies.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.2
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• pp.122-132
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• 2013

In this research the development of unstructured grid discretization solution techniques is presented. The purpose is to describe such a conservative discretization scheme applied for experimental validation work. The objective of this paper is to better establish the effects of mesh generation techniques on velocity fields and particle deposition patterns to determine the optimal aerodynamic characteristics. In order to achieve the objective, the mesh surface discretization approaches used the VLA prototype manufacturing tolerance zone of the outer surface. There were 3 schemes for this discretization study implementation. They are solver validation, grid convergence study and surface tolerance study. A solver validation work was implemented for the simple 2D and 3D model to get the optimum solver for the VLA model. A grid convergence study was also conducted with a different growth factor and cell spacing, the amount of mesh can be controlled. With several amount of mesh we can get the converged amount of mesh compared to experimental data. The density around surface model can be calculated by controlling the number of element in every important and sensitive surface area of the model. The solver validation work result provided the optimum solver to employ in the VLA model analysis calculation. The convergence study approach result indicated that the aerodynamic trend characteristic was captured smooth enough compared with the experimental data. During the surface tolerance scheme, it could catch the aerodynamics data of the experiment data. The discretization studies made the validation work more efficient way to achieve the purpose of this paper.

• Proceedings of the Korean Statistical Society Conference
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• 2004.11a
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• pp.195-198
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• 2004

One Important problem in a cancer microarray study is to identify a set of genes from which a molecular prognostic indicator can be developed. In parallel with this problem is to validate the chosen set of genes. We develop in this note a K-fold cross validation procedure by combining a 'pre-validation' technique and a bootstrap resampling procedure in the Cox regression . The pre-validation technique predicts the microarray predictor of a case without having seen the true class level of the case. It was suggested by Tibshirani and Efron (2002) to avoid the possible over-fitting in the regression in which a microarray based predictor is employed. The bootstrap resampling procedure for the Cox regression was proposed by Sauerbrei and Schumacher (1992) as a means of overcoming the instability of a stepwise selection procedure. We apply this K-fold cross validation to the microarray data of 92 gastric cancers of which the experiment was conducted at Cancer Metastasis Research Center, Yonsei University. We also share some of our experience on the 'false positive' result due to the information leak.

• Journal of the Korean Data and Information Science Society
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• v.6 no.1
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• pp.63-71
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• 1995

We have consider the study of local influence for smoothing parameter estimates in spline regression model with heteroscedasticity. Practically, generalized cross-validation does not work well in the presence of heteroscedasticity. Thus we have proposed the local influence measure for generalized cross-validation estimates when errors are heteroscedastic. And we have examined effects of diagnostic by above measures through Hyperinflation data.

• Journal of the Chungcheong Mathematical Society
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• v.32 no.1
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• pp.149-156
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• 2019

This paper present the global generalized cross validation as the appropriate choice of the regularization parameter in the preconditioned Gl-LSQR method in solving image deblurring problems. The regularization parameter, chosen from the global generalized cross validation, with preconditioned Gl-LSQR method can give better reconstructions of the true image than other parameters considered in this study.

• Journal of the Korea Society for Simulation
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• v.19 no.1
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• pp.153-160
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• 2010

Most part of errors in software development process are included during the stage of requirements definition and design. And correction or elimination of errors from those stages requires much more efforts and costs than those from the later part of software development process. However, despite of the importance of the validation of requirement definition and design stages, several kinds of problem have made it hard to be done successfully. Therefore, in this paper, we introduce a novel validation process for the preliminary design stage. The validation process is based on simulations of model and it can be used to validate requirements and model simultaneously. Models in the validation process will take only the behavior of software and be built on Ptolemy framework. The usability of our validation process is confirmed with a case study over DNS system environment. And the result of simulation shows well-known errors or vulnerabilities can be found with simulations of model which has the behavior of software. This means our validation process can be used as a process to validate requirements and models during the early stage of software development process.