• Electronics and Telecommunications Trends
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• v.35 no.5
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• pp.30-42
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• 2020

Unlike in previous generations of mobile technology, machine learning (ML)-based self-healing research trend are currently attracting attention to provide high-quality, effective, and low-cost 5G services that need to operate in the HetNets scenario where various wireless transmission technologies are added. Self-healing plays a vital role in detecting and mitigating the faults, and confirming that there is still room for improvement. We analyzed the research trend in self-healing framework and ML-based fault detection, fault diagnosis, and fault compensation. We propose that to ensure that self-healing is a proactive instead of being reactive, we have to design an ML-based self-healing framework and select a suitable ML algorithm for fault detection, diagnosis, and outage compensation.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2000.11a
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• pp.155-159
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• 2000

This paper describes the self healing characteristics of metalized polypropylene film(MPPF) under ac condition. PDs were generally observed at relatively low voltage, and the PDIVs were differently varied depending on the number of pre-self healing due to void defects. Several pre-self healing events took place at lower voltage than the critical breakdown voltage of PPF. Self healing mainly occurred at pin tips, wrinkle sides, and cross points of wrinkles. The applied voltage at self healing was increased with PPF thickness. The burn out area at self healing was also increased with the applied voltage and PPF thickness. The peak currents in a grounding conductor at self healing was also increased with the applied voltage.

• Corrosion Science and Technology
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• v.8 no.6
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• pp.223-226
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• 2009

Polymer coatings are commonly applied to metal substrates to prevent corrosion in aggressive environments such as high humidity and under salt water. Once the polymer coating has been breached, for example due to cracking or scratches, it loses its effectiveness, and corrosion can rapidly propagate across the substrate. The self-healing system we will describe prevents corrosion by healing the damage through a healing reaction triggered by the actual damage event. This self-healing coating solution can be easily applied to most substrate materials, and our dual-capsule healing system provides a general approach to be compatible with most common polymer matrices. Specifically, we expect an excellent anti-corrosion property of the self-healing coatings in damaged parts coated on galvanized metal substrates.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.295-299
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• 2021

Recently, interest in maintenance has been increasing due to the enlargement and aging of infra structures. Therefore, a new paradigm is required to secure and improve the durability of structures differentiated from the past. Accordingly, research on smart concrete incorporating the concept of self-healing into concrete is being actively conducted. In this study, the crack healing performance and durability performance of self-healing concrete applied with a hydrogel containing biomineral-forming microorganisms were evaluated. As a result of evaluating the dispersion of the hydrogel in concrete, it was confirmed that the hydrogel was well distributed in concrete matrix with a dispersion coefficient of 0.35 to 0.46. The crack healing performance evaluation was verified by a water permeability test, and showed a recovery rate of 95% or more at the age of 28 days, confirming the applicability of self-healing concrete. The durability performance of self-healing concrete was evaluated in terms of resistance to penetration of chloride ion and freezing and thawing. Regardless of the mixing of the hydrogel, the same level of durability performance was shown for various compressive strength level. Therefore, it was confirmed that the microbial admixture did not affect concrete durability. In the future, long-term crack healing performance and durability verification studies should be supplemented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.303-304
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• 2021

The present study aims to examine the practical potentials of crack self-healing pillet produced using inorganic materials.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.6
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• pp.1158-1168
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• 1994

The paper proposes a distributed control self-healing algorithm for a line failure to improve the restoration time. This proposed self-healing algorithm acquired the fast restoration time by reducing the number of control messages and the queueing delay. And the reduction of queueing delay was attained by the ASC_NULL(Available Spare Channel_NULL) message which informs neighbor nodes that a source node has no available spare channel to reduce the waste of time during the rerouting. It is difficult for this proposed self-healing algorithm to be compared with other self-healing algorithms, because each self-healing algorithm has different simulation conditions. So, the performance of the proposed self-healing algorithm was compared with only NETRATS(NETwork Restoration Algorithm for Telecommunication Systems). The results of the simulation showed that the proposed self-healing algorithm was better than NETRATS in the restoration time.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.4
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• pp.77-82
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• 2000

This paper describes the self healing characteristics of a metalized polypropylene film(MPPF) by voids under a.c condition. PDIVs were increased with the number of pre-self healing due to void defects, and several pre-self healing events took place at lower voltage than the critical breakdown voltage of a PPF. Self healing mainly occurred at pin tips, wrinkle sides, and cross points of wrinkles, and the main self healing voltage was increased with PPF thickness. The burn out area at self healing was increased with the applied voltage, and the peak currents in a grounding conductor at self healing was also increased with the applied voltage.

• Elastomers and Composites
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• v.50 no.3
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• pp.167-174
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• 2015

Anionic epoxy compound was synthesized and added to asphalt aiming to prepare self-healing asphalt. Epoxy-modified asphalt showed excellent modification effect and healing effect as well. The results revealed that with 5% addition of polymer the tensile strength, impact strength and complex shear modulus of the polymer-modified asphalt increased by 65%. 64% and 35%, respectively. It seems that high interaction occurs between polymer and asphalt matrix. Self-healing efficiency of the polymer-modified asphalt based on tensile strength showed 100%, comparing to 79% of straight asphalt. In impact experiment the polymer-modified asphalt showed 99% of healing efficiency, comparing to 77% of straight asphalt. In rheological experiment the polymer-modified asphalt showed 103% of healing efficiency, comparing to 72% of straight asphalt. It appears that the ionic bonding existing in epoxy polymers contributed to high values of self-healing efficiency. The polymer which has high intermolecular force fills the crack of the asphalt, pulling the opponent side each other, and so the original properties were restored.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.321-322
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• 2023

This study compared the compressive strength and healing strength to confirm the self-healing performance of mortar incorporating Bioinspired Self-healing Capsule (BSC) into cement composites as part of a study to mitigate the problem of durability deterioration due to cracks in concrete structures. As a result of the evaluation, it was found that the healing performance decreased as the mixing ratio of the BSC capsule increased.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.113-121
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• 2019

In this study, self - healing microcapsules which can be mixed directly with cement composites were prepared, and the quality and crack healing performance of cement composites with self - healing microcapsules were evaluated. In the past, it has been focused on evaluating self-healing capsules and crack healing properties. Therefore, self - healing microcapsules have been studied for their effect on the quality of cement composites when mixed with cement composites. The table flow and the air flow rate of the cement composite material mixed with self-healing microcapsules were found to have no significant influence on table flow and air volume regardless of mixing ratio. Compressive strength and splitting tensile strength tended to decrease with increasing capsule mixing ratio. As a result of evaluation of crack healing properties according to water flow, initial water permeability decreased, and reaction products were generated over time and cracks were healed.