• 제목/요약/키워드: Self healing

검색결과 484건 처리시간 0.023초

A Review on Nanocomposite Based Electrical Insulations

  • Paramane, Ashish S.;Kumar, K. Sathish
    • Transactions on Electrical and Electronic Materials
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    • 제17권5호
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    • pp.239-251
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    • 2016
  • The potential of nanocomposites have been drawing the intention of the researchers from energy storage to electrical insulation applications. Nanocomposites are known to improve dielectric properties, such as the increase in dielectric breakdown strength, suppressing the partial discharge (PD) as well as space charge, and prolonging the treeing, etc. In this review, different theories have been established to explain the reactions at the interaction zone of polymer matrix and nanofiller; the characterization methods of nanocomposites are also presented. Furthermore, the remarkable findings in the fields of epoxy, cross-linked polyethylene (XLPE), polypropylene and polyvinyl chloride (PVC) nanocomposites are reviewed. In this study, it was observed that there is lack of comparison between results of lab scale specimens and actual field aged cables. Also, non-standardization of the preparation methods and processing parameters lead to changes in the polymer structure and its surface degradation. However, on the positive side, recent attempt of 250 kV XLPE nanocomposite HVDC cables in service may deliver a promising performance in the coming years. Moreover, materials such as self-healing polymer nanocomposites may emerge as substitutes to traditional insulations.

IEC61850 기반의 통신방식을 이용한 스마트 배전운영시스템용 보호협조 알고리즘 개발 (Development of Protection Coordination Algorithm for Smart Distribution Management System using Communication Method based on IEC61850)

  • 추철민;윤상윤;권성철;추경용;진영규;최면송
    • 전기학회논문지
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    • 제61권10호
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    • pp.1412-1419
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    • 2012
  • In this paper, we propose the protection coordination algorithm using communication methode based on IEC 61850. The communication protocol in power distribution management system has been issued by IEC standard, IEC61850 of them, which was made for substation automation system, has researched to apply into power distribution system, even though the standard is not a suitable for the system. In smart distribution management system' launched in 2009, the communication network based on the ethernet network for IEC 61850 has been designed to apply the self-healing concept, which is to perform the system protection through the communication between remote terminal units(RTU) according to the standard. However, it is first time to apply the scheme in the real. Thus, this paper proposed the protection algorithm and consideration for applying communication method and introduced the result of demonstration.

자가 치유 시스템을 위한 목표 트리 기반 평가 기법 (Goal Tree based Testing Method for Self-healing System)

  • 민동욱;김영덕;고재헌;이현숙;김훈기;정석용;박정민
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2009년도 추계학술발표논문집
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    • pp.436-440
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    • 2009
  • 자가 치유란 시스템에서 발생될 수 있는 에러나 오류를 미리 예상하거나 감지하고 시스템 스스로 치유함으로써 시스템의 오동작을 최소화하는 것을 의미한다. 자가 치유 시스템의 신뢰성을 높이기 위해서는 정확한 테스트 기법이 필요하다. 하지만 기존의 테스트 기법은 성공 또는 실패만으로 나타내기때문에 정량적인 평가가 불가능하다. 따라서 본 논문에서는 자가 치유 시스템이 달성해야 할 목표를 추출하고 관계에 따라 트리로 작성하여 이를 기반으로 시스템의 자가 치유 기법의 성공률을 정량적 측정하는 기법을 제안한다. 본 기법을 통해 자가 치유 시스템의 치유 결과를 정량적으로 평가 가능하고, 평가결과를 기반으로 치유 전략에 대한 문제점이 분석 가능하므로 자가 치유 시스템의 신뢰성 향상이 가능하다.

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치매요양시설 디자인에 대한 시설근무자의 평가 및 요구 - 부산시 D 치매노인 전문병원을 중심으로 - (Design Evaluation and Needs of the Staff for Nursing Home for the Dementia - Focused on D hospital for the Elderly with Dementia -)

  • 오찬욱
    • 한국실내디자인학회논문집
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    • 제14권6호
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    • pp.157-167
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    • 2005
  • The demands of nursing home for the dementia are rapidly increasing. However, there are no enough nursing homes and design guidelines for it. This study was intended to examine the needs of the staff for the nursing home design and suggest the design guidelines of the Korean nursing home for the dementia. The subjects were 15 nurses and 18 care givers who worked in D hospital for the elderly with dementia in Busan. Data were collected by the self-administered questionnaire. The findings were as follows; First, the most important design element in nursing home for the dementia which the staff mentioned was 'healing environment' and then 'function' and 'maintenance' Second, the care-givers were more satisfied with their facility design than the nurses. Third, the staff pointed out that 'the relation between individual room and nursing station', namely, short distance between them, and 'enough wandering space' had to be considered at first in design process of nursing home with dementia. Also, the comfort and intimate interior mood, fresh air and sunlight were also pointed out as the important elements in nursing home design for the dementia.

Traditional medicines for common dermatological disorders in Mauritius

  • Mahomoodally, Mohamad Fawzi;Hossain, Ziad Dil
    • 셀메드
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    • 제3권4호
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    • pp.31.1-31.8
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    • 2013
  • This study has been geared to document primary information on common complementary and alternative medicines (CAM) used to treat and/or manage common dermatological disorders in Mauritius, a tropical multicultural island in the Indian Ocean. Data from 355 key informants was collected via a semi-structured questionnaire. Pearson correlation and Chi-squared test were performed to delineate any association. Quantitative indexes including the Importance Value (IV) and fidelity value were calculated. Results tend to indicate that cultural reasons were behind the use of CAM among Mauritians and traditional knowledge was mainly acquired either from parents/relatives or from self-experience. Among the medicinal plants mentioned, Aziadiracta indica (IV = 0.78) and Paederia tomentosa (IV = 0.70) were found to be most used plants. Calendula officinalis (IV = 0.15), Centella asiatica (IV = 0.22) and Agauria salicifolia (IV = 0.11) were also recorded to be used for common dermatological disorders though greatly under-utilised. Animal products were mentioned by 38.0% respondents and cow ghee was found to be commonly used in the management of measles (IV = 0.88). Spiritual healing was found to be used mainly for measles and warts. Given the plethora of novel information documented from the present survey, it can be suggested that the Mauritian population still relies to a great extent on CAM which needs to be preserved and used sustainably. Nonetheless, further investigation is required to probe the possible active constituents that could be the basis of an evidence based investigation to discover new drugs.

가골 신연술을 이용한 양측성 다발열 단중족증의 치료 (1예 보고) (Operative Treatment of the Bilateral Multiple Rays Brachymetatarsia using Callotasis (A Case Report))

  • 권세원;박강희;소재완
    • 대한족부족관절학회지
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    • 제14권2호
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    • pp.186-189
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    • 2010
  • Among congenital brachymetatarsias fourth metatarsal bone shortening is most common form and unusually involves multiple metatarsal bones. We report a case of the patient with bilateral 1st and 4th multiple rays brachymetatarsia treated with callostasis. Twenty eight months after procedure, right side showed 1st metatarsal lengthening about 11.5 mm (29.23%) and 4th metatarsal 17.86 mm (35.87%). Twenty one months later, left side showed 1st metatarsal lengthening about 14.58 mm (36.8%) and 4th metatarsal 20.52 mm (43.01%). In healing index right side showed 1st metatarsal 3.4 month/cm, 4th metatarsal 2.5 month/cm and left side showed 1st metatarsal 4.2 month/cm, 4th metatarsal 2.3 month/cm. Final follow-up results presented excellent outcome in cosmetic problem, easy wear of shoes, and measurement of patient's self satisfaction.

부분적 광파장 변환 노드를 이용한 광인터넷 복구 (Optical Internet Recovery using Partial Wavelength Conversion Nodes)

  • 황호영
    • 한국인터넷방송통신학회논문지
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    • 제12권3호
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    • pp.83-88
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    • 2012
  • 이 논문에서는 광통신망에서 광파장 변환 능력이 통신망 복구 성능에 미치는 영향을 분석한다. 기존의 연구에서는 그물망 형태의 광통신망에서 약 30% 정도의 광파장 변환 능력이 제공된다면 Call Blocking 확률의 측면에서 100%의 광파장 변환 능력을 가질 때와 거의 같은 정도의 성능을 나타낸다고 알려져 왔다. 그러나 이는 정상적인 광파장 채널을 대상으로 하였을 때의 결과이고, 복구를 위한 예비 경로 및 예비 광파장을 포함한 복구 성능에 대한 광파장 변환 능력의 영향은 충분히 분석되지 않고 있다. 본 논문에서는 광파장 변환 능력이 예비 광파장의 이용 효율 면에서 망 복구 성능에 미치는 영향을 분석하였다. 실험 결과는 광파장 변환 능력과 복구를 위한 예비 광파장의 이용 효율성은 서로 비례하는 것으로 나타나, 정상적인 광파장 채널만을 대상으로 했던 기존 연구 결과와는 다름을 알 수 있다.

농촌 마을정원 설계를 위한 정원요소 선호도 분석 (A Study on Garden Elements Preference for the Rural Community Garden Design)

  • 박미정;최진아;강성진;전보배;진현승
    • 농촌계획
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    • 제21권4호
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    • pp.95-102
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    • 2015
  • The study aims to examine preferences between community residents and visitors in designing a rural community garden. It analyzed diverse aspects of a garden design including garden's function, location, management subject, components and so on. The survey was conducted on residents or visitors participants with a self-administered survey questionnaire. The results revealed that both residents and visitors highly preferred a rural community garden as a role of relaxation, appreciation, and healing. Meanwhile, there were differences of preference for location and garden components between residents and visitors. The results implicated that residents' preference and characteristics of a community are essential in designing a rural community garden, which will lead to sustainable garden construction.

Role of Charges of the Surface-grafted Polymer Chains for Aqueous Lubrication at a Nonpolar Interface

  • Ron, Troels;Madsen, Jan Busk;Nikorgeorgos, Nikolaos;Lee, Seunghwan
    • Tribology and Lubricants
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    • 제30권5호
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    • pp.247-255
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    • 2014
  • Charged polymer chains, i.e., polyelectrolytes, are known to show superior aqueous lubricating properties compared to those of neutral polymer chains, especially in brush conformation. This is primarily because of the incorporation of a large amount of counterions within the polymer layers and the consequently increased osmotic pressure. However, this effect is active only when the polymer chains remain immobilized even under tribostress, which is not realistic for high-contact pressure tribological applications, especially when they are irreversibly immobilized on tribopair surfaces. In contrast, with free polymers, which can be included as surface-active additives in the base lubricant (water), long-term lubricating performance based on "self-healing" properties is readily expected. In order to assess whether the superior aqueous lubricating properties of polyelectrolyte chains are valid for free polymers too, this study reviews recent studies on the tribological properties of many charged biopolymer and synthetic copolymers at a nonpolar, hydrophobic interface. In contrast to the irreversibly immobilized polyelectrolyte chains, free polyelectrolyte chains show inferior aqueous lubricating properties compared to their neutral counterparts owing to charge accumulation and the consequently impeded surface adsorption on the nonpolar surface. Nevertheless, bovine submaxillary mucin (BSM), a representative biopolymer, shows a sufficiently effective surface adsorption and aqueous lubricating capabilities even at neutral pH without losing the polyanionic characteristics.

만성 관절염환자의 지지간호 효과 (Effects of the supportive nursing care on the chronic arthritis patients : outcomes of the treatment for 8-week followup.)

  • 김명자;조계화;강성실;송효정
    • 기본간호학회지
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    • 제6권3호
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    • pp.559-569
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    • 1999
  • The purpose of this study is to identify the effects of the supportive nursing care for arthritis patients enrolled in a rheumatoid clinic. To achieve this purpose, this study adopted a quasi-experimental, pre- and post-test research design, categorized subjects into experimental and control groups. Outpatient clinic nurse alloted the subjects by experimental and control groups and nurse researcher meets the experimental subject with in-depth, direct personal interview and advices via telephone for 8 weeks. During this pre and after the treatment period, the level of pain, uncertainty, self-efficacy, family support, and perception for health were measured. Analyses for the measured results for pre- and post-test showed that the supportive program conducted during this study decreased the level of uncertainty and increased the perception of family support in experimental group. So, the supportive healing interpersonal communication service proved to be effective and this result justifies the argument that the role of the nursing professionals at out-patient clinic should be extended for the more qualified care for the patient.

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