• 제목/요약/키워드: properties changes

검색결과 5,872건 처리시간 0.037초

산불에 노출된 가공송전선의 기계적 및 전기적 특성 거동 연구 (Mechanical and Electrical Properties Behavior Study of Overhead Conductor due to Forest Fire)

  • 장용호;김병걸;김상수;한세원;김진한
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
    • /
    • pp.108-109
    • /
    • 2008
  • Forest Fire can cause a serious damage to overhead conductors. Therefore, the detailed investigation for the changes of mechanical and electrical properties of damaged conductors should be carried out to understand the effect of forest fires on conductors. This is very much important to maintain transmission line safely. Especially, this paper describes the changes of mechanical and electrical properties of flame exposed conductor. The detailed will be given in the text.

  • PDF

우유의 렌넷 젤에 대한 기계적 특성 (Rennet-induced gels and their mechanical properties)

  • 최종우
    • 농업과학연구
    • /
    • 제38권4호
    • /
    • pp.711-716
    • /
    • 2011
  • Casein micelles are the basic building block of rennet-induced gels. The stiffness of these gels is increased with reaction time. This is probably due to the continuous participation of activated casein micelles into growing network. Dual binding model of casein micelles, which explains assembly of casein and colloidal calcium phosphate, can provides fairly reasonable explanation for the changes in mechanical properties of rennet-induced gels made from different milk pHs and varying colloidal calcium phosphates. The changes in stiffness of these gels would be used for controlling textural properties of cheeses.

반복세탁 및 건조방법이 드레스셔츠의 물성에 미치는 영향(II) (The Changes in Properties of Dress Shirts by Repeated Washing and Drying (II))

  • 이송자;성수광;권헌선
    • 한국의류산업학회지
    • /
    • 제1권3호
    • /
    • pp.259-263
    • /
    • 1999
  • This study was carried out to investigate the changes of thermal properties such as warmth retaining and contact warm/cool feeling of commercial dress shirts by repeated washing and drying by sun and dryer. Three kinds of fabrics such as cotton 100%, cotton/polyester 80/20% and polyester 100% were repeatedly washed and dried, and then used as specimen. Thermo Labo II type was employed to measure the thermal properties. At the same time, structural properties such as thickness, weight, bulk density, porosity, moisture vapor permeability and air permeability were analysed.

  • PDF

Time-dependent effects on dynamic properties of cable-stayed bridges

  • Au, Francis T.K.;Si, X.T.
    • Structural Engineering and Mechanics
    • /
    • 제41권1호
    • /
    • pp.139-155
    • /
    • 2012
  • Structural health monitoring systems are often installed on bridges to provide assessments of the need for structural maintenance and repair. Damage or deterioration may be detected by observation of changes in bridge characteristics evaluated from measured structural responses. However, construction materials such as concrete and steel cables exhibit certain time-dependent behaviour, which also results in changes in structural characteristics. If these are not accounted for properly, false alarms may arise. This paper proposes a systematic and efficient method to study the time-dependent effects on the dynamic properties of cable-stayed bridges. After establishing the finite element model of a cable-stayed bridge taking into account geometric nonlinearities and time-dependent behaviour, long-term time-dependent analysis is carried out by time integration. Then the dynamic properties of the bridge after a certain period can be obtained. The effects of time-dependent behaviour of construction materials on the dynamic properties of typical cable-stayed bridges are investigated in detail.

산불에 노출된 가공송전선의 기계적 및 전기적 특성 거동 (Mechanical and Electrical Properties of Overhead Conductor due to Forest Fire)

  • 김병걸;장용호;김상수;한세원
    • 한국전기전자재료학회논문지
    • /
    • 제21권11호
    • /
    • pp.1042-1048
    • /
    • 2008
  • Forest Fire can cause a serious damage to overhead conductors. Therefore, the detailed investigation for the changes of mechanical and electrical properties of damaged conductors should be carried out to understand the effect of forest fires on conductors. This is very much important to maintain transmission line safely. Especially, this paper describes the changes of mechanical and electrical properties of flame exposed conductor. Overhead conductors temperature were almostly 55$\sim$65% of ambient temperature. Tensile Strength decreased according to incerase of Forest Fire temperature. The detailed will be given in the text.

Al이 도핑된 투명전극용 ZnO 박막의 수소 열처리에 관한 특성연구 (Post-annealing of Al-doped ZnO films in hydrogen atmosphere)

  • 오병윤;정민창;이웅;명재민
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
    • /
    • pp.58-61
    • /
    • 2005
  • In an effort to improve the electrical properties of ZnO:Al transparent electrode films, post-annealing treatment in hydrogen atmosphere was attempted with varying annealing time at 573 K for compatibility with typical display device fabrication processes. It was observed that carrier concentrations and mobilities increased with longer annealing time with small changes in crystallinity. This resulted in substantial decrease in resistivity from $4.80{\times}10^{-3}$ to $8.30{\times}10^{-4}{\Omega}cm$ due to increased carrier concentration. Such improvements in electrical properties are attributed to the passivation of the grain boundary surfaces. The optical properties of the films, which changed in accordance with the Burstein-Moss effect, were consistent with the observed changes in electrical properties.

  • PDF

침채류의 Texture에 영향을 미치는 요인 및 연화 방지 (The Factors Affecting on the Texture of Salted Vegetables and Prevention of Tissue Softening)

  • 이영남
    • 한국식품영양학회지
    • /
    • 제5권2호
    • /
    • pp.163-169
    • /
    • 1992
  • The changes in the various chemical compositions and textural properties of salted vegetables during salting and fermentation were reviewed with 25 papers published from 1981 to 1991 The changes in the texture of vegetables were largely affected by the properties of pectic substances, and additional factors such as salt type, salt concentration, salting time, temperature, preheating treatment, enzyme, salt mixtures, salt-fermented fish and garlic contents, were concerned complexly.

  • PDF

Application of On-line System for Monitoring and Forecasting Surface Changes for Korean Peninsula

  • Lee, Sang-Hoon
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.268-273
    • /
    • 1998
  • This study applies an on-line system, which employes an adaptive reconstruction technique to monitor and forecast ocean surface changes. The system adaptively generates an appropriate synthetic time series with recovering missing measurements for sequential images. The reconstruction method incorporates temporal variation according to physical properties of targets and anisotropic spatial optical properties into image processing techniques. This adaptive approach allows successive refinement of the structure of objects that are barely detectable in the observed series. The system sequentially collects the estimated results from the adaptive reconstruction and then statistically analyzes them to monitor and forecast the change in surface characteristics.

  • PDF

홍화 염색 모직물의 자외선에 의한 성능 변화 연구 (A Study on the Properties Changes of Wool Fabrics Dyed with Safflower under Ultraviolet(UV)-Light)

  • 신윤숙;최승연
    • 한국의류산업학회지
    • /
    • 제10권2호
    • /
    • pp.249-253
    • /
    • 2008
  • The purpose of this study was to investigate the properties changes of wool fabrics dyed with safflower red and yellow colorants under Ultraviolet(UV)-light. For this purpose, the wool fabrics dyed with safflower red and yellow colorants were compared with each other after uv-light exposure in terms of K/S value, color changes(${\Delta}E$), morphology, and strength retention. K/S value rapidly decreased with increasing exposure time, but K/S value of the samples dyed with safflower yellow colorants decreased less than that of the samples dyed with safflower red colorants. In color changes, as increasing exposure time, $L^*$ and $b^*$ increased, $a^*$ decreased, and thereby ${\Delta}E$ increased in the samples dyed with safflower red colorants, $L^*$ increased, $a^*$ and $b^*$ decreased, and so ${\Delta}E$ increased in the samples dyed with safflower yellow colorants, indicating fading away by uv-light and changes of hue, value and chroma value. But the color change of samples dyed with safflower yellow colorants was less than that of samples dyed with safflower red colorants. SEM pictures showed a severe degradation by uv exposure, regardless of colorants type. Tensile strength slowly decreased until 14 days, and rapidly decreased until 21 days and slowly decreased. Strength retention of the samples dyed with safflower yellow colorants was higher than that of the samples dyed with safflower red colorants.