• 제목/요약/키워드: ageing time

검색결과 207건 처리시간 0.026초

RTV 실리콘 코팅재의 전기적 열화 특성 연구 (Study on electrical ageing properties of ATV silicone coatings)

  • 한세원;조한구;한동희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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    • pp.35-39
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    • 2003
  • An ageing characteristics of RTV coating materials by corona discharge have been studied. The recovery of a hydrophobicity of RTV coating materials with the thickness of $300{\mu}m$ was in identical with a bulk silicone materials. The hydrophobicity of RTV coating materials has been almost lost when its were discharged during 40 seconds by corona with 10kV, and recovered after about 45 hours. But the resistivity of RTV coating materials has not been recovered after 45 hours, even though after 80 hours the 95% of initiation resistivity value has been recovered. There was no critical compounds(such as Si and Al) changes on RTV surfaces by the corona discharge treatment until 100 seconds. In the test of arc erosion, it was seen that the coating sample with silicone rubber as a base material have more longer bum-out time than other samples with FRP or glass base.

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Evaluation of Senescence Induced Prematurely by Stress. Application for cosmetic active ingredients

  • Morvan, Pierre-Yves;Romuald Vallee
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.285-290
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    • 2003
  • Living cells are continuously subject to all sorts of stress such as ultraviolet rays on skin cells. Tests made in various laboratories show that when young fibroblasts (Le. at the beginning of their proliferate life) were repeatedly put under stress at subletal doses, they acquired a phenotype similar to Senescence Induced Prematurely by Stress (SIPS). The work presented hereafter was made on a new model of senescence induced prematurely by stress from ultraviolet Brays (UVB). The human fibroblast model was put under repeated UVB stress, causing SIPS. Several ageing biomarkers were used in order to characterise the cells that underwent stress:. an increase in the proportion of positive cells with senescence associated $\beta$-galactosidase activity (SA $\beta$-gal) measured by a specific coloration,. the proportion in the different morphological stages that fibroblasts undergo during culture visualised by microscopic observation,. the expression of genes known for overexpressing during senescence, particularly fibronectin and apolipoprotein J, measured by Real Time-PCR,. the common deletion of 4,977 bp in mitochondrial DNA, evaluated by nested PCR. Studying the variation of these 4 biomarkers, we have evaluated the protective effect of a Laminaria digitata extract (LDE) that can be used as a natural active ingredient for anti-ageing cosmetics.

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열처리 인공촉진열화가 배접지의 광학적 및 기계적 특성에 미치는 영향 (Optical & Mechanical Characteristics of Lining Papers by the Artificial Heat Ageing Treatment)

  • 정선화;최경화;박지희;강영석;윤경동
    • 보존과학연구
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    • 통권30호
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    • pp.93-102
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    • 2009
  • This study was carried out to investigate the effect of artificial accelerated ageing treatment on the permanence of lining papers produced from Korea and Japan. As time gone by, organic cultural properties are affected by chemical and physical deterioration because of various factors including the conditions of preservation environment and their material properties. In the public historical storage or owned as private collections, are vulnerable to sever amages caused by poor preservation environment as well as by other natural factors. In this study, the deterioration behaviors of lining paper in optical & mechanical properties were discussed. Overall, lining papers produced from Korea showed lower reduction in mechanical strength properties compared to the lining papers produced from Japan.

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적극적 노년생활과 세대 간 가족관계 - 노일일자리사업 데이터를 활용한 실증분석 - (Active Ageing and Inter-Generational Relationship: Empirical Evidence from Public Job Creation Program for Elderly)

  • 이석원
    • 한국정책학회보
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    • 제21권1호
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    • pp.337-361
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    • 2012
  • 본 연구는 노인의 사회적 고립과 외로움을 치유할 수 있는 세대 간 가족관계를 국가가 적극적 노년정책 수단을 통해 개선을 유도하는 것이 가능하다는 실증적 증거를 제공하기 위해 수행되었다. 이를 위한 실증분석의 핵심과제는 역방향의 인과관계의 존재에 의한 선택편의를 통제하는 작업이며 이를 위하여 '적격비참여자'로 비교집단을 구성하여 도구변수로 실증모형을 추정하는 전략을 채택하였다. 분석결과 노년기의 생활패턴이 적극적으로 변화함에 따라 자녀들과의 가족관계는 경제적 연대측면이나 유대적 연대측면 모두에서 유의미하게 개선되는 것으로 나타났다. 또한 이러한 개선효과는 자녀세대와 동거하지 않는 노인부모들에게 집중되어 발생하는 것으로 나타났다. 본 연구의 결과는 세대 간 가족관계의 개선이 적극적 노년정책의 새로운 편익으로 추가될 수 있는 실증적 근거를 제시하였다는데 정책적 의미를 갖는다.

Exploring dietitians' views on digital nutrition educational tools in Malaysia: a qualitative study

  • Zahara Abdul Manaf;Mohd Hafiz Mohd Rosli;Norhayati Mohd Noor;Nor Aini Jamil;Fatin Hanani Mazri;Suzana Shahar
    • Nutrition Research and Practice
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    • 제18권2호
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    • pp.294-307
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    • 2024
  • BACKGROUND/OBJECTIVES: Dietitians frequently use nutrition education tools to facilitate dietary counselling sessions. Nevertheless, these tools may require adaptation to keep pace with technological advancements. This study had a 2-fold purpose: first, to identify the types of nutrition education tools currently in use, identify their limitations, and explore dietitians' perspectives on the importance of these tools; second, to investigate the features that dietitians prefer in digital nutrition education tools. SUBJECTS/METHODS: A semi-structured face-to-face interview was conducted among 15 dietitians from selected public hospitals, primary care clinics, and teaching hospitals in Malaysia. Inductive thematic analysis of the responses was conducted using NVivo version 12 software. RESULTS: Most dietitians used physical education tools including the healthy plate model, pamphlets, food models, and flip charts. These tools were perceived as important as they facilitate the nutrition assessment process, deliver nutrition intervention, and are time efficient. However, dietitians described the current educational tools as impersonal, outdated, limited in availability due to financial constraints, unhandy, and difficult to visualise. Alternatively, they strongly favoured digital education tools that provided instant feedback, utilised an automated system, included a local food database, were user-friendly, developed by experts in the field, and seamlessly integrated into the healthcare system. CONCLUSION: Presently, although dietitians have a preference for digital educational tools, they heavily rely on physical nutrition education tools due to their availability despite the perception that these tools are outdated, impersonal, and inconvenient. Transitioning to digital dietary education tools could potentially address these issues.

복합 고분자 애자의 열화 진단 데이터 분석 기법 (Introduction of Data Analysis Method for Ageing Diagnosis of Polymer Insulator)

  • 최남호;이병성;조성수;한상옥
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1611-1613
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    • 1999
  • This paper introduces the data processing method and the measurement of the leakage current flowing through polymer insulators. For ageing diagnosis of polymer insulator, data aquisition system was developed to record the leakage current of insulator being tested. Hence, we have gained information for life time from its leakage current. the DAS is protected against over-voltage which would develop in the event of a flashover of the test sample.

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황색종 통담배의 숙성기간중 주요 이화학성의 변화 (THE CHANGE OF MAJOR PHYSICO-CHEMICAL PROPERTIESIN FLUE-CURED TOBACCO PACKED IN HOGSHEAD DURING AGEING)

  • 민영근;이미자;이경구;이상하
    • 한국연초학회지
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    • 제9권1호
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    • pp.65-71
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    • 1987
  • In order to obtain the most suitable ageing term of Flue-cured tobacco in natural condition, leaf tobacco packed in hogshead and stored in leaf tobacco warehouse for 4 years, and the changes of major physico-chemical components were examined at three months intervals, As storage time goes by, except the moisture content, general chemical components of leaf tobacco were decreased until about 9-15 months of storage. Among them, decrement of total sugar was the most significant. After 18 months storage, the chlorophyll was decreased by 50% of initial stage. The content of essential oils, solanone, damascenone, megastigmatrienone I, II, III, IV, were approached the maximum between 12 months and 15 months of storage and then lessened by degrees.

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Global Today - 원자력발전소 저전압 케이블의 노화에 대한 적격, 상태 모니터링 및 관리 (1) (QUALIFICATION, CONDITION MONITORING, AND MANAGEMENT OF AGEING OF LOW VOLTAGE CABLES IN NUCLEAR POWER PLANT)

  • 강기식
    • 전기저널
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    • 통권451호
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    • pp.46-58
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    • 2014
  • 2013년 말, 전세계에 운행중인 원자력발전소 원자로는 434기로 총 용량은 371.6GW(e)이며, 이 중 약 80%는 20년 이상 사용되었다. 많은 회원국들은 최우선 순위로 자신들의 원자력발전소 운행 기간을 원래의 예상 기간인 30~40년 보다 길게 허용했다. 그렇다면 원자력발전소의 어려운 환경에서 기존의 케이블을 어떻게 적격 판정할 것인가. 본 원고는 원자력발전소의 저전압 케이블의 적격, 상태 모니터링 및 관리에 대한 연구 사항을 기술하였다.

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EPDM 및 실리콘 재질의 폴리머현수애자의 특성 비교 (The Comparison of EPDM and Silicone in Housing Materials of Polymeric Suspension Insulators)

  • 이병성;이재봉;송일근;한상옥
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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    • pp.6-10
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    • 2003
  • In our country, the housing materials of polymeric outdoor insulators have mainly been used EPDM or silicone rubber. EPDM housing materials had been widely used in the field for the first time. The reason why silicone has the high cost of production. But recently, most of the manufacturers that newly developed polymeric insulators make its choice of silicone housing. EPDM showed a good resistance to tracking. We compared the various characteristics for EPDM and silicone insulators that have similar type and design. Silicone insulators have more performance in flashover voltage test and leakage current measurement because of a good water repellent than EPDM ones. Also, the property of EPDM compared with silicone insulators greatly decreased after aging test in combined acceleration ageing facilities for 1000 hours.

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송전선로에 사용되는 갭형 피뢰기 소자의 뇌임펄스 전류특성 (Characteristics of Lightning Impulse Current of Zno Block for Transmission Line Arrester with External Gap)

  • 조한구;유대훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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    • pp.61-62
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    • 2009
  • This paper describes the characteristics of lightning impulse current of ZnO block for transmission line arrester with external gap. The ageing parameters of lightning arresters ate impulse current, moisture ingress, temperature ageing and so on. Especially it is important to estimate the change of electrical characteristics by impulse current. Total energy applied to the ZnO arrester each time is $4/10{\mu}s$, 30kA and $2/20{\mu}s$, 10kA impulse current. Before and After the test, the residual voltage variation of varistors passed was below 5%. According to the test, it is thought that the ZnO arrester shows good stability with impulse current test.

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