• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.483-489
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• 2016

The typical methods used for inspecting ferromagnetic pipes include the ultrasonic testing (UT) contact method and the following non-contact methods: magnetic flux leakage (MFL), electromagnetic acoustic transducers (EMAT), and remote field eddy current testing (RFECT). Among these methods, the RFECT method has the advantage of being able to establish a system smaller than the diameter of a pipe. However, the method has several disadvantages as well, including different sensitivities and difficult-to-repair coil sensors which comprise its array system. Therefore, a giant magneto-resistance (GMR) sensor was applied to address these issues. The GMR sensor is small, easy to replace, and has uniform sensitivity. In this experiment, the GMR sensor was used to measure remote field and defect signal characteristics (in the axial and radial directions) in a ferromagnetic pipe. These characteristics were measured in an effort to investigate standard defects at changing depths within a pipe. The results show that the experiment successfully demonstrated the applicability of the GMR sensor to RFECT signal detection in ferromagnetic pipe.

• Health Policy and Management
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• v.33 no.2
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• pp.173-184
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• 2023

Background: The coronavirus disease 2019 pandemic has been challenging the healthcare service, i.e., the vitalization of the point of care accompanying self-testing in vitro diagnostic medical devices (IVDs). This study aims to suggest priority criteria to classify self-testing IVDs using the analytic hierarchy process technique. Methods: Two dimensions of the characteristics embedded in the IVDs and the diseases to be diagnosed with self-testing IVDs were parallelly considered and independently investigated. In addition, three expert panels consisting of laboratory medical doctors (n=11), clinicians (n=10), and citizens (n=11) who have an interest in the selection of self-testing IVDs were asked to answer to questionnaires. Priorities were derived and compared among each expert panel. Results: First of all, ease of specimen collection (0.241), urgency of the situation (0.224), and simplicity of device operation (0.214) were found to be the most important criteria in light of the functional characteristics of self-testing IVDs. Medical doctors valued the ease of specimen collection, but the citizen's panel valued self-management of the disease more. Second, considering the characteristics of the diseases, the priority criteria were shown in the order of prevalence of diseases (0.421), fatality of disease (0.378), and disease with stigma (0.201). Third, medical doctors responded that self-testing IVDs were more than twice as suitable for non-communicable diseases as compared to communicable diseases (0.688 vs. 0.312), but the citizen's group responded that self-testing IVDs were slightly more suitable for infectious diseases (0.511 vs. 0.489). Conclusion: Our findings suggested that self-testing IVDs could be primarily classified as the items for diagnosis of non-communicable diseases for the purpose of self-management with easy specimen collection and simple operation of devices, taking into account the urgency of the situation as well as prevalence and fatality of the disease.

• The Journal of Korean Academic Society of Nursing Education
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• v.19 no.4
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• pp.675-683
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• 2013

Purpose: Nineteen articles were analyzed to gather opinions and nursing implications about NIPT recently launched. Methods: Nineteen articles were selected from EBSCO (eBook business collection), Google Scholar, and two Korean academic d-bases with key words 'prenatal screening testing', 'prenatal genetic diagnostic testing', NIPT or 'cell free DNA (cfDNA)'. Authors developed a framework for analyzing the 19 articles including opinions and suggestions for future implications. Results: Eleven articles written by the first author affiliated with medicine or genetics, viewed NIPT as promising because of safety, accuracy, early detectability and cost effectiveness. Articles written by journalists or authors affiliated with history and ethics were concerned with the possible risk of ELSI (ethical, legal, social issues), erratic interpretation of test results, and lack of genetic counseling service. Conclusion: With consideration of Korean clinical, and legal circumstances, not only pregnant women and families but also health professionals must prepare for clinical NIPT implications including updating prenatal genetic testing, counseling services, protecting ELSI and amulticultural team approach.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.3-12
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• 2006

The purpose of this study is to describe the Non-Destructive Testing(NDT) of the rockbolt and investigate the applicability of the NDT methods to estimate the integrity of the rockbolt. To examine the rockbolt integrity including rockbolt itself and grouting material, two methods are adopted: numerical and experimental methods. In the numerical method, the numerical code DISPERSE is used to analyze the dispersion of the rockbolt. The dispersion curve shows the effects of the thickness and stiffness of grouted materials on the embedded rockbolt. Therefore, the optimal frequency for the integrity test of the rockbolt is obtained: 20~120kHz in L(1,0) mode. In the experimental methods, destructive and non-destructive tests are carried out in a laboratory. In the non-destructive test, the low frequency mode generated by an impact and t he high frequency mode generated by an ultrasonic transducer seem to characterize the rockbolt condition readily. The experimental results show that the guided waves attenuate more significantly when the stiffness of the grouted material increases and/or the zone of the defect increases. Meanwhile, the ultimate capacity of rockbolt was evaluated through the pull-out tests and is compared to the NDT results. This study demonstrates that the NDT is a valuable tool for the rockbolt integrity evaluation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.3
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• pp.122-131
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• 2003

In this study, some characteristics of conductive and non-conductive adhesive inter-connections are derived, based on data from literature and own projects. Assembly of flip chip on flex is taken as a carrier. Potential failure mechanisms of adhesive interconnections reported in literature are reviewed. Some methods that can be used to evaluate the quality of adhesive interconnections and to evaluate their aging behavior are given. Possible finite element simulation approaches are introduced and the required critical materials properties are summarized. Response to temperature and moisture, resistance to reflow soldering and resistance to rapid change in temperature and humidity are elaborated. The effect of post cure during accelerated testing is discussed. This study shows that only a combined approach using finite element simulations, and use of appropriate experimental evaluation methods can result in revealing, understanding and quantifying the complex degradation mechanisms of adhesive interconnections during aging.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.377-382
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• 1995

Conventional measurement methods using ultrasonic wave or x-ray, eddy current for non-destructive testing(NDT) in nuclear power plants and other industrial plants have been performed as the method of contact with objects to be inspected. With this reason these methods have been taken relatively much time and the inspected area is limited by the location of probe or film. But holographic interferometry which is a non-contact optical measurement method using a coherent light source has an advantage that the quantitative measurement can be performed at a time. In this paper a new method using holographic interferometry and image processing for detecting internal flaws of pressure vessels is presented.

• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.157-167
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• 1999

Among several non-destructive testing methods, ultrasonic pulse velocity method and rebound index method have been widely used for the evaluation of concrete strength. However, such methods might not provide accurate estimated results since factors influencing the relationship between strength and either ultrasonic pulse velocity or rebound index are not considered. In this paper, the evaluation method of concrete strength using rod-wave velocity measured by impact-resonance method is proposed. A basic equation is obtained by the linear regression of velocity vs, strength data at specific age and then, aging factor is employed in the equation to consider the difference of the increasing rate between wave velocity and strength. Strengths predicted by the proposed equation agree well with test results. Furthermore, the combined method of rod-wave velocity and rebound index is proposed.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.4
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• pp.253-261
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• 2017

In this paper, a corner detection method based on a new non-cornerness measure is presented. Rather than evaluating local gradients or surface curvatures, as done in previous approaches, a non-cornerness function is developed that can identify stable corners by testing an image region against a set of desirable corner criteria. The non-cornerness function is comprised of two steps: 1) eliminate any pixel located in a flat region and 2) remove any pixel that is positioned along an edge in any orientation. A pixel that passes the non-cornerness test is considered a reliable corner. The proposed method also adopts the idea of non-maximum suppression to remove multiple corners from the results of the non-cornerness function. The proposed method is compared with previous popular methods and is tested with an artificial test image covering several corner forms and three real-world images that are universally used by the community to evaluate the accuracy of corner detectors. The experimental results show that the proposed method outperforms previous corner detectors with respect to accuracy, and that it is suitable for real-time processing.

• Journal of the Korea Society of Computer and Information
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• v.26 no.9
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• pp.125-132
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• 2021

At a time when non-face-to-face classes are being held for a long time due to Corona (COVD-19), research on non-face-to-face teaching and learning methods is needed. Existing teaching and learning methods are limited in their application to non-face-to-face classes as they present face-to-face practical and experiential teaching methods. In this study, we present a method of utilizing the extended reality (XR: eXtended Reality) technology for the 5AL (5 Activity Learning) teaching method, which is a teaching and learning method selected by the Institute for University Education Innovation. The 5AL teaching method consists of PBL Learning, Havruta Learning, Flipped Learning, Smart Activity Learning, and Gamification Learning. In this study, a method of combining the released extended reality contents with 5AL was presented. In addition, we developed content that integrates the 5 learning methods of 5AL and confirmed the learning effect through testing.

• Animal Bioscience
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• v.36 no.7
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• pp.1003-1009
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• 2023

Objective: The objective was to compare (pedigree-based) best linear unbiased prediction (BLUP), genomic BLUP (GBLUP), and single-step GBLUP (ssGBLUP) methods for genomic evaluation of growth traits in a Mexican Braunvieh cattle population. Methods: Birth (BW), weaning (WW), and yearling weight (YW) data of a Mexican Braunvieh cattle population were analyzed with BLUP, GBLUP, and ssGBLUP methods. These methods are differentiated by the additive genetic relationship matrix included in the model and the animals under evaluation. The predictive ability of the model was evaluated using random partitions of the data in training and testing sets, consistently predicting about 20% of genotyped animals on all occasions. For each partition, the Pearson correlation coefficient between adjusted phenotypes for fixed effects and non-genetic random effects and the estimated breeding values (EBV) were computed. Results: The random contemporary group (CG) effect explained about 50%, 45%, and 35% of the phenotypic variance in BW, WW, and YW, respectively. For the three methods, the CG effect explained the highest proportion of the phenotypic variances (except for YW-GBLUP). The heritability estimate obtained with GBLUP was the lowest for BW, while the highest heritability was obtained with BLUP. For WW, the highest heritability estimate was obtained with BLUP, the estimates obtained with GBLUP and ssGBLUP were similar. For YW, the heritability estimates obtained with GBLUP and BLUP were similar, and the lowest heritability was obtained with ssGBLUP. Pearson correlation coefficients between adjusted phenotypes for non-genetic effects and EBVs were the highest for BLUP, followed by ssBLUP and GBLUP. Conclusion: The successful implementation of genetic evaluations that include genotyped and non-genotyped animals in our study indicate a promising method for use in genetic improvement programs of Braunvieh cattle. Our findings showed that simultaneous evaluation of genotyped and non-genotyped animals improved prediction accuracy for growth traits even with a limited number of genotyped animals.