• Title, Summary, Keyword: Field aged

Search Result 414, Processing Time 0.048 seconds

Influence of Applied Electric Field on Low Temperature Degradation of Y-TZP (인가 전압이 Y-TZP의 저온열화에 미치는 영향)

  • 장주웅;이홍림;김대준;오남식;이득용
    • Journal of the Korean Ceramic Society
    • /
    • v.34 no.12
    • /
    • pp.1254-1260
    • /
    • 1997
  • Influence of applied electric field on the low temperature degradation of 3 mol% YaO3 stabilized tetragonal zirconia polycrystals(3Y-TZP) was investigated using X-ray diffractometry of specimens aged under the dc field of 1.1 kV/mm in silicone oil both of 12$0^{\circ}C$-21$0^{\circ}C$. After the aging, the tetragonal to monoclinic phase transformation was observed only on the specimen surface of 3Y-TZP faced to the anode. This indicated that the surface was overcrowded with oxygen ions as a result of diffusion of oxygen vacancies toward the cathode-sided surface. To elucidate an influence of the applying time of the electric field on the extent of the degradation of 3Y-TZP in air, specimens were aged fore 0-2 hours under the electric field in the oil bath of 12$0^{\circ}C$ and then subsequently aged for 3h at 22$0^{\circ}C$ in air. The longer the specimens were aged under the field, the more extensive the transformation to the monoclinic phase was on the specimen surface faced to the cathode, probably originated from a high diffusion rate of oxygen ions due to a steep oxygen vacancy concentration gradient.

  • PDF

Development of the Estimating Equation for Children's High-Exposure to Habitat's Magnetic Field using Particle Swarm Optimization (Particle Swarm Optimization을 이용한 소아고노출 생활자계 추정식 개발)

  • Hwang, Gi-Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.14 no.5
    • /
    • pp.1085-1092
    • /
    • 2010
  • This paper describes the development of estimating equation for under 16 aged children's exposure to habitat's magnetic field for 24 hours by using particle swarm optimization(PSO) algorithm, which was carried out by using the measured database collected from the exposure survey to Korean habitat's magnetic field as to under 16 aged Korean students such as preschooler, children in elementary school, and children in middle school. Sex, age, residence type, size of habitation site, distance from power line, and power transmission voltage are used as the input data of estimating 24 hour's personal exposure to magnetic field. And distribution of 24 hour's personal exposure to magnetic field, exposure characteristic to magnetic field, and exposure characteristic to magnetic field according to special conditions, are analyzed for under 16 aged children.

Inhibitory Effect of Aged Petroleum Hydrocarbons on the Survival of Inoculated Microorganism in a Crude-Oil-Contaminated Site

  • Kang, Yoon-Suk;Park, Youn-Jong;Jung, Jae-Joon;Park, Woo-Jun
    • Journal of Microbiology and Biotechnology
    • /
    • v.19 no.12
    • /
    • pp.1672-1678
    • /
    • 2009
  • We studied the effects of aged total petroleum hydrocarbons (aged TPH) on the survival of allochthonous diesel-degrading Rhodococcus sp. strain YS-7 in both laboratory and field investigations. The aged TPH extracted from a crude-oil-contaminated site were fractionized by thin-layer chromatography/flame ionization detection (TLC/FID). The three fractions identified were saturated aliphatic (SA), aromatic hydrocarbon (AH), and asphaltene-resin (AR). The ratio and composition of the separated fractions in the aged TPH were quite different from the crude-oil fractions. In the aged TPH, the SA and AH fractions were reduced and the AR fraction was dramatically increased compared with crude oil. The SA and AH fractions (2 mg/l each) of the aged TPH inhibited the growth of strain YS-7. Unexpectedly, the AR fraction had no effect on the survival of strain YS-7. However, crude oil (1,000 mg/l) did not inhibit the growth of strain YS-7. When strain YS-7 was inoculated into an aged crude-oil-contaminated field and its presence was monitored by fluorescent in situ hybridization (FISH), we discovered that it had disappeared on 36 days after the inoculation. For the first time, this study has demonstrated that the SA and AH fractions in aged TPH are more toxic to an allochthonous diesel-degrading strain than the AR fraction.

Effect of Priming on Germination of Aged Soybean Seeds

  • Park, E.;Choi, Y.S.;Jeong, J.Y.;Lee, S.S.
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.44 no.1
    • /
    • pp.74-77
    • /
    • 1999
  • The object of this study is to determine the effect of priming on the germination ability and seedling emergence of aged soybean seeds in lab and field conditions. Artificial or natural procedure for seed aging was applied in this study. One seed lot was artificially aged for 3 to 5 days at 42$^{\circ}C$ with high relative humidity (nearly RH 100%), and the other one was stored at room temperature for 17 months. Aged seeds were osmoconditioned in -1.1 MPa polyethylene glycol 8000 (PEG) solution for 3 days at $25^{\circ}C$ and air-dried. When Danyeobkong was aged for 4 days average germination was 61.5%, however, this improved to 98.5% after the priming treatment. Improvement of seed germination by priming the aged seed was consistent with large seed sized Jangyeobkong cultivar, indicating that the priming was effective in enhancing seed germinability regardless of seed size. Priming aged seeds also resulted in good stand establishment in the field trials. Germination of aged seeds of Danyeobkong without priming was 17.0%, whereas that of primed ones was 66.4%.

  • PDF

Electrical Characteristics of Polymer Insulators with Field Aging (현장열화에 따른 폴리미애자의 전기적 특성)

  • 한재홍;이병성;김찬영;한용희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.522-525
    • /
    • 1999
  • The electrical characteristics of 3 year field-aged polymer insulators which dismounted from five regions were investigated. There was a little difference in PD inception voltage depending on the manufacturers and the regions. The results between PD and SD showed a close relation. There were no significant changes in electrical properties. So, it can be considered that the field-aged insulators are sound for the present.

  • PDF

Impact of Aged-related Experience on Knowledge and Attitude toward Aged - Dental Hygiene Students - (일부 치위생과 학생들의 노인관련 경험이 노인에 대한 지식 및 태도에 미치는 영향에 관한 연구)

  • Lee, Yeong-Ae;Yoon, Hee-Suk;Kim, Young-Sun
    • Journal of dental hygiene science
    • /
    • v.9 no.5
    • /
    • pp.551-556
    • /
    • 2009
  • To investigate effect of aged-related experience on the knowledge and attitude of department of dental hygiene students for the old people. The the survey, which is done by 292 students in D health college, is enforced from August to October 2009. Following result is the data. Analyzed by using SPSS 14.0 version. 1. For the knowledge toward aged, in case of educated has the high level of knowledge (p < 0.05) in Physical-physiological, Social-familial field. But there's no some difference in Psychological field. 2. Whether doing education or not, there's no some difference toward attitude to aged. 3. Whether living together or not, there's no difference about knowledge or attitude. But people who has experience as volunteer shows positive attitude to aged.(p < 0.05) 4. The factors which affects to knowledge about aged are education and attitude for aged. 5. The factors which affects to attitude to aged are volunteering experience and knowledge for aged.

  • PDF

Observation of Electrical Properties in Field-aged Photovoltaic Module (Field aged 태양전지모듈의 노화현상에 따른 전기적 특성 관찰)

  • Kang, Gi-Hwan;Yu, Gwon-Jong;Ahn, Hyung-Keun;Han, Deuk-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.28-32
    • /
    • 2004
  • In this paper, degradation in field-aged PV modules including degradation of interconnect, discoloration of encapsulant and hot spot have been observed and analyzed. From the results, photovoltaic module installed for 6 years shows around 16% drop of electrical properties due to the interconnect degradation and PV module passed 18 years has been found to drop of around 20% mainly by the encapsulant discoloration. Furthermore the difference between low and high temperature of PV array at hot spot goes up to $30^{\circ}C$ and it leads to interconnect degradation. On the other hands, the temperature difference was observed to be around $15^{\circ}C$ at the encapsulant discoloration spot of PV array.

  • PDF

The Context of Housing for the Old Age in Korea with Perspective of Franklin's Social Constructionism Model (프랭클린(Franklin)의 사회구성주의 모델 관점으로 본 한국의 노인주택 맥락)

  • 유병선;전경화;홍형옥
    • Journal of Korean Home Management Association
    • /
    • v.22 no.1
    • /
    • pp.103-114
    • /
    • 2004
  • This study was performed by the literature review on housing of the aged in Korea with social constructionism perspective. This kind of research may be utilized as a theoretical framework for performance of any systems of housing for the aged. In terms of structural context, the value of conventional custom of filial piety thoughts and duty for family are being collapsed, which nay be suitable to the change of society, should be considered for positive acceptance of changes in ideology. In terms of institutional context, a method to grope for housing for the aged should be established through amicable cooperation between organizations of legalization concerned. In terms of organizational context, there is no organization that exclusively concern housing for the aged until now, thus, development of concrete manual is required for jobs of service in current department of policy for the aged. In terms of operational context, the service may include the understanding of characteristics of the aged and design of housing may also change the service of administration, and as cooperation in the local community care systems may change the service to the aged in the field. Connection of these services and operation of these organizations nay be required in the field to manage housing. Finally in terms of intersubjective context, as the form and method of housing management service is important, with understanding of the social meaning and importance on the role of manager.

Assessment of Reliability and Load Carrying Capacity of Aged Wharf Structure of Pier Type (노후된 잔교식 부두의 신뢰성 및 내하력 평가)

  • 조효남;김성훈;김종규;이승재;최영민
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • /
    • pp.71-78
    • /
    • 1994
  • The main objectives of the study may be stated as follows : \circled1 the acquisition of fundamental updated data for the assessment of aged wharf structures of pier type based on systematic static/dynamic load testing \circled2 the study of techniques and methods for field testing \circled3 realistic safety and load carrying capacity assessment based on practical reliability analysis. In this study field testing of real structure is performed and the results are compared with those of the 2D and 3D linear structural analysis. It may be seen that the practical reliability methods can be applied for the safety and capacity assessment of aged wharf structures of pier type.

  • PDF

Characteristics analysis of field aged distribution surge arresters (경년에 따른 배전용 피뢰기의 열화특성)

  • Cho, Seong-Soo;Kim, Ju-Yong;Kim, Chan-Young;Song, Il-Keun;Park, Jung-Shin
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.2323-2325
    • /
    • 1999
  • This paper presents characteristics of the aged and new 18kV surge arresters. In order to investigate aging characteristics, we measured total leakage current and resistive leakage current using specially made leakage current measurement system and also investigated $tan{\delta}$ of the arresters and microstructure of the elements. Through the investigation we found that all of the arresters does not aged for 2 years field operation.

  • PDF