• 제목/요약/키워드: Various temperature

검색결과 12,797건 처리시간 0.044초

양생온도 변화 및 버블시트 두께변화에 따른 콘크리트의 온도이력특성 (Temperature History of Concrete Corresponding to Various Bubble Sheets Layer and Curing Temperature)

  • 홍석민;백대현;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2008년도 추계 학술논문 발표대회
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    • pp.21-25
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    • 2008
  • In this paper, the temperature history and the strength development of concrete corresponded to various bubble sheets layer and curing temperature. Based on the results, In case of the test temperature of -5℃, concrete subject in the exposure condition, result in a frost damage at initial stage by a fall of below zero temperature. In case of the combination of PE film and non woven fabric was after 36 hour, and combination of bubble sheet over double, a tremendous insulating effect of bubble sheet over double is confirmed due to the temperature of concrete fall of below zero temperature after 60 hours. Meanwhile, regarding the -15℃ of temperature, special measure for insulation curing is necessary to secure stability against early frost damage because frost damage was not affected by the lapping thickness of bubble sheet subjected to severe cold weather condition.

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TPS Analysis of Various Metal Plates for Belt Source Evaporation in AMOLED Manufacturing

  • Hwang, Chang-Hun
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1603-1606
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    • 2007
  • The TPS (Temperature Programmed Sublimation) technology has been developed to monitor the plane evaporation of the organic films and introduced in SID2007, P53.[4] The Alq3 organic film is deposited on various metal surface such as Cu, Ti, Invar, STS to sublimate. The TPS signal confirms that the Alq3 film consists of nano scale film phase and bulk phase on all the metal plates. The sublimation temperature of the Alq3 film was much lower ($130^{\circ}C$) than the vapor temperature ($265^{\circ}$) of the Alq3 powder.

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돼지 액상정액을 위한 희석액 및 저온보존에 관한 연구 (A Study on Extender and Lower Temperature Storage for Fresh-extended Porcine Semen)

  • 김명철;김용준;조정곤;이수진;이재일;김인철;손동수
    • 한국임상수의학회지
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    • 제18권4호
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    • pp.345-349
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    • 2001
  • The aim of this study was to investigate the effect of sperm preservation according to the various kinds of commercially available semen extenders and to investigate the effect of sperm preservation according to the various temperature storages of fresh-extended porcine semen. To investigate the effect of sperm preservation according to the various kinds of commercially available semen extenders, porcine semens diluted in 3 semen extenders, Beltsville Thawing Solution(BTS), Androhep and Kiev, were cooled at $8^{\circ}C$ storage temperature with a controlled cooling rate of $2-4^{\circ}C$/h. Motility, progressive motility, normal sperm(%) and sperm morphology were assessed comparatively. In motility and progressive motility, Androhep extenders revealed better result than other extenders. In normal sperm(%) and sperm morphology, 3 semen extenders revealed similar results. To investigate the effect of sperm preservation according to the various temperature storages of fresh-extended porcine semen, porcine semens diluted in BTS extender, were cooled at 3 storage temperatures($8^{\circ}C$, $12^{\circ}C$ and $17^{\circ}C$) with a controlled cooling rate of $2-4^{\circ}C$/h. Motility, progressive motility, normal sperm(%) and sperm morphology were assessed comparatively. In motility and progressive motility, $8^{\circ}C$ treatment group revealed better result than $12^{\circ}C$ and $17^{\circ}C$ treatment groups. In normal sperm(%) and sperm morphology, 3 temperatures of treatment groups revealed similar results.

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수면과 온도 (Sleep and Temperature)

  • 김혜금;서완석
    • 수면정신생리
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    • 제23권2호
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    • pp.47-52
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    • 2016
  • Changes in core body temperature are closely related to initiation and maintenance of sleep, and are influenced by various factors such as air temperature, room temperature, clothing, human activities, and medications. These factors are closely related to sleep fragments, insomnia and other sleep disorders. Understanding the effect of the temperature related to human surroundings on the core body temperature and sleep, will be useful for understanding the physiology of sleep and to treat sleep disorders.

환경에 따른 MZT/LZT 디스크의 tribological 특성 (Tribological Behavior of MZ/LZT disk under Various Environmental Conditions)

  • 박용식;김대은
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제29회 춘계학술대회
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    • pp.53-60
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    • 1999
  • As the flying height decreased, it is essential that hard disk drives perform reliable under various environmental conditions. In this paper the tribological characteristics of a head/disk interface are investigated under various temperature, relative humidity, altitude and outgas conditions. Specially, Contact-Start-Stop(CSS) tests were performed to assess the stiction, acoustic emission, slider take-off behavior, and track average amplitude(TAA). It is shown that the surface damage and head failure are accelerated by high temperature and humidity as well as low ambient pressure.

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환경에 따른 헤드/디스크 인터페이스의 마찰 특성 (Tribological Characteristics of Head/disk Interface under Various Environmental Conditions)

  • 박용식;김대은
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1998년도 제28회 추계학술대회
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    • pp.131-138
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    • 1998
  • It is essential that hard disk drives perform reliable under various temperature, humidity, and ambient pressure conditions. In this paper the tribological characteristics of a head/disk interface are investigated under various environmental conditions. Specially, Contact-Start-Stop(CSS) tests were performed to assess the stiction and slider take-off behavior. It is shown that the surface damage is accelerated by high temperature and humidity as well as low ambient pressure.

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기판 온도에 따른 OLED 소자의 발광 특성 (Luminescent Properties of OLEO Devices with Various Substrate Temperatures)

  • 김정택;백경갑;주성후
    • 한국전기전자재료학회논문지
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    • 제22권11호
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    • pp.956-960
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    • 2009
  • The characteristics of organic films can be affected by the temperature of evaporation source because the temperature of evaporation source has an effect on substrate temperature during OLED fabrication process using the thermal evaporation. To investigate the characteristics of OLED devices fabricated by using thermally damaged organic films, I-V-L and half life-time in OLED devices fabricated with various substrate temperatures were measured. During emission layer(EML) evaporation, OLED devices with a structure of ITO(100 nm)/ELM200(50 nm)/NPB(30 nm)/$Alq_3$(55 nm)/LiF(0.7 nm)/Al(100 nm) were fabricated at various substrate temperatures(room temperature, $30^{\circ}C$, $40^{\circ}C$, and $50^{\circ}C$). The characteristics of current density and luminance versus applied voltage in OLED devices fabricated shows that many electrical currents flowed and high brightness appeared at low voltage, but that the lifetime of OLED devices dropped suddenly. This phenomenon explained that the crystallization of $Alq_3$ thin film appeared owing to the substrate heating during evaporation.

The Characteristics of Pulverized Coal Combustion in the Two Stage Cyclone Combustor

  • Joo, Nahm-Roh;Kim, Ho-Young;Chung, Jin-Taek;Park, Sang-Il
    • Journal of Mechanical Science and Technology
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    • 제16권9호
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    • pp.1112-1120
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    • 2002
  • Numerical investigations on air staging and fuel staging were carried out with a newly designed coaxial cyclone combustor, which uses the method of two stage coal combustion composed of pre-combustor and main combustor. The pre-combustor with a high air/fuel ratio is designed to supply gas at high temperature to the main combustor. To avoid local high temperature region in this process, secondary air is injected in the downstream. Together with the burned gas supplied from the pre-combustor and the preheated air directly injected into main combustor, coals supplied through the main burner react rapidly at a low air/fuel ratio. Strong swirling motion of cyclone combustor keeps the wall temperature high, which makes slagging combustion possible. Alaska, US coal is used for calculations. Predictions were made for various coal flow rates in the main combustor for fuel staging and for the various flow rate of secondary air in the pre-combustor for air staging. In-scattering angles are also chosen as a variable to increase residence times of coal particles. Temperature fields and particle trajectories for various conditions are described. Predicted temperature variations at the wall of the combustor are compared with corresponding experimental data and show a similar trend. The in-scattering angle of 20° is recommended to increase the combustion efficiency in the main chamber.

레이져 표면 경화 공정에서 신경회로망을 이용한 경화층 깊이 예측 (Estimation of Hardening Layer Depths in Laser Surface Hardening Processes Using Neural Networks)

  • 우현구;조형석;한유희
    • 한국정밀공학회지
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    • 제12권11호
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    • pp.52-62
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    • 1995
  • In the laser surface hardening process the geometrical parameters, especially the depth, of the hardened layer are utilized to assess the integrity of the hardening layer quality. Monitoring of this geometrical parameter ofr on-line process control as well as for on-line quality evaluation, however, is an extremely difficult problem because the hardening layer is formed beneath a material surface. Moreover, the uncertainties in monitoring the depth can be raised by the inevitable use of a surface coating to enhance the processing efficiency and the insufficient knowledge on the effects of coating materials and its thicknesses. The paper describes the extimation results using neural network to estimate the hardening layer depth from measured surface temperanture and process variables (laser beam power and feeding velocity) under various situations. To evaluate the effec- tiveness of the measured temperature in estimating the harding layer depth, estimation was performed with or without temperature informations. Also to investigate the effects of coating thickness variations in the real industry situations, in which the coating thickness cannot be controlled uniform with good precision, estimation was done over only uniformly coated specimen or various thickness-coated specimens. A series of hardening experiments were performed to find the relationships between the hardening layer depth, temperature and process variables. The estimation results show the temperature informations greatly improve the estimation accuracy over various thickness-coated specimens.

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터빈 발전기 고정자단부의 온도상승에 관한 연구 (A Study on the Temperature-rise at the Stator end portion of Turbine Generator)

  • 임한석
    • 기술사
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    • 제10권1호
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    • pp.10-14
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    • 1977
  • In accordance with introducing extra high voltage system, system power plants have to be operated in underexcited condition, which causes temperature rise at the stator end portion of turbine generator. This Paper deals with (1) various elements affecting temperature rise and (2) methods of pre-estimating temperature rise.

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