• 제목/요약/키워드: Self healing

검색결과 483건 처리시간 0.022초

이동통신망 자가 치유를 위한 기계학습 연구동향 (Research Status on Machine Learning for Self-Healing of Mobile Communication Network)

  • 권동승;나지현
    • 전자통신동향분석
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    • 제35권5호
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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.

커패시터용 MPPF의 교류전압 인가시 전기적 특성 (The Electrical Characteristics of MPPF for Capacitor Applications under AC condition)

  • 정종욱;곽희로;박중신
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2000년도 학술대회논문집
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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.

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Self-healing Coatings for an Anti-corrosion Barrier in Damaged Parts

  • Cho, Soo Hyoun
    • Corrosion Science and Technology
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    • 제8권6호
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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.

미생물 혼입 자기치유 콘크리트의 균열 치유성능 및 내구성능 (Crack-healing and durability performance of self-healing concrete with microbial admixture)

  • 추인엽;우상균;이병재;이윤;이효섭
    • KEPCO Journal on Electric Power and Energy
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    • 제7권2호
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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.

동기식 광전송망 복구를 위한 자체 치유 알고리즘 (Self-Healing Algorithm for The Restoration of Synchronous Optical Networks)

  • 장윤선;지윤규;김홍주
    • 한국통신학회논문지
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    • 제19권6호
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    • pp.1158-1168
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    • 1994
  • 본 논문은 선로 장애에 대한 분산 제어 자체 치유 알고리즘을 제안한 것으로 복구시간을 향상시키는데 중점을 두었다. 복구를 위해 망에서 교환되는 제어 메시지의 개수를 작게 하고, 이웃 노드들에게 더 이상 복구에 사용된 예비채널이 없음을 이리 알리는 ASC_NULL(Available Spare Channel_NULL) 신호를 만들어 복구 경로 설정 과정에서 낭비되는 시간 지연을 줄임으로써 빠른 복구 시간을 얻을 수 있었다. 다른 여러 자체 치유 알고리즘들과의 객관적인 비교는 여러 조건들의 차이로 어려우므로 NETRATS(NETwork Restoration Algorithm for Telecommunication Systems)와의 비교만을 시뮬레이션 하였다. 시뮬레이션의 결과에서 제안된 알고리즘이 NETRATS보다 향상된 복구 시간을 가진다는 것을 알 수 있었다.

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보이드에 의한 MPPF의 셀프힐링 특성 연구 (A Stud on the Self Healing Characteristics of MPPF by Voids)

  • 박하용;곽희로
    • 조명전기설비학회논문지
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    • 제14권4호
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    • pp.77-82
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    • 2000
  • 본 논문은 교류전압 인가시 보이드 형상에 따른 금속증착 폴리프로필렌 필름(Metalized Polypropylene Film : MPPF)의 셀프힐링 특성에 대해 연구하였다. 보이드 결함으로 인해 발생하는 프리 셀프힐링의 횟수가 증가함에 따라 PDIV는 증가하였으며, 프리 셀프힐링은 FPF의 절연파괴전압보다 낮은 전압에서 발생하였다. 셀프힐링은 주로 핀형, 주름형, X/Y형 보이드의 에지, 주름선상 및 교차점에서 발생하였으며, 주셀프힐링 전압은 PFP의 두께에 따라 증가하였다. 또한, 셀프힐링시 증착금속의 비산면적은 인가전압에 따라 증가하였으며, 셀프힐링시의 피크전류는 MPPF에 인가된 전압에 따라 증가하였다.

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Self-Healing Asphalt Prepared by using Ionic Epoxy Resin

  • Lee, Young-Jik;Seo, Jun-Young;Kim, Seo-Yeon;Lee, Seung-Hyun;Hong, Young-Keun
    • Elastomers and Composites
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    • 제50권3호
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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.

자기치유용 캡슐 혼입율에 따른 모르타르 블록의 자기치유 특성 (Self-Healing Characteristics of Mortar Blocks according to the Mixing Ratio of Self-Healing Capsules)

  • 윤주호;김채영;나범수;이재인;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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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.

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자기치유 마이크로 캡슐을 혼합한 시멘트 복합재료의 품질 및 균열 치유 특성에 관한 실험적 연구 (A Study on Crack Healing Properties of Cement Composites Mixed with Self-healing Microcapsules)

  • 최연왕;오성록;김철규;남은준
    • 한국구조물진단유지관리공학회 논문집
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    • 제23권1호
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    • pp.113-121
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    • 2019
  • 본 연구에서는 시멘트 복합재료와 직접 혼합 가능한 자기치유 마이크로 캡슐을 제조하였으며, 자기치유 마이크로 캡슐이 혼합된 시멘트 복합재료의 품질 및 균열 치유 성능 특성을 평가하였다. 종래의 경우 자기치유 캡슐 제조와 균열 치유 특성 평가에만 치중되어 평가되어 왔다. 따라서 자기치유 마이크로 캡슐은 시멘트 복합재료와 혼합시 시멘트 복합재료의 품질에 미치는 영향이 있기 때문에 이에 대한 검토를 수행하였다. 자기치유 마이크로 캡슐을 혼합한 시멘트 복합재료의 테이블 플로우 및 공기량 평가 결과 혼합율에 관계없이 테이블 플로우 및 공기량은 큰 영향이 없는 것으로 나타났다. 압축강도 및 쪼갬인장강도는 캡슐 혼합율이 증가할수록 강도가 감소하는 경향이 나타났다. Water Flow에 따른 균열 치유 특성 평가 결과 초기 투수량이 감소하는 결과가 나타났으며, 시간 경과에 따라 반응 생성물 발생하여 균열이 치유되는 것을 확인 할 수 있었다.