• Title/Summary/Keyword: wide temperature range

Search Result 1,005, Processing Time 0.035 seconds

Development of Low Anchoring Strength Liquid Crystal Mixtures for Bistable Nematic Displays

  • Stoenescu, D.;Lamarque-Forget, S.;Joly, S.;Dubois, J.C.;Martinot-Lagarde, Ph.;Dozov, I.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.97-100
    • /
    • 2005
  • The recent Bistable Nematic ($BiNem{(R)}$) LCD technology presents long term bistability, high level passive matrix multiplexing and high optical quality. The BiNem device, based on anchoring breaking, needs specific low anchoring strength materials - alignment layers and liquid crystal mixtures. We present here our approach to develop nematic mixtures with wide enough temperature range and low zenithal anchoring energy.

  • PDF

Deterministic Fracture Mechanics Analysis of Pressurized Thermal Shock

  • M. J. Jhung;Park, Y. W.
    • Nuclear Engineering and Technology
    • /
    • v.30 no.5
    • /
    • pp.470-484
    • /
    • 1998
  • An analysis program for the evaluation of pressure vessel integrity under pressurized thermal shock (PTS) is developed. For given material properties and transient history such as temperature and pressure, the stress distribution is calculated and then stress intensity factors are obtained for a wide range of crack sizes. The stress intensity factors are compared with the fracture toughness to check if cracking is expected to occur during the transient. Using this program a round robin problem of PTS during a small break loss of coolant transient has been analyzed as a part of the international comparative assessment study. The allowable maximum reference nil-ductility transition temperatures are determined for various crack sizes.

  • PDF

A PROPOSED CORRELATION FOR CRITICAL FLOW RATE OF WATER FLOW

  • KIM, YEON-SIK
    • Nuclear Engineering and Technology
    • /
    • v.47 no.1
    • /
    • pp.135-138
    • /
    • 2015
  • A new correlation predicting the idealized critical mass-flow rates of water for subcooled and saturated liquid water including two-phase water flow was developed for a wide range of upstream stagnation pressures (e.g., 0.5-20.0 MPa). A choking correction factor dependent on the upstream stagnation pressure and subcooled temperature was introduced into a new correlation, and its values were suggested to satisfy the idealized nozzle data within 10% error ranges. The suggested correlation will be instructive and helpful for related studies and/or engineering works.

Partitioning of Si in Fe-Zr-Si-B Nanocrystalline Alloys

  • Waniewska, A.Slawska;Greneche, J.M.;A.Inoue
    • Journal of Magnetics
    • /
    • v.4 no.1
    • /
    • pp.1-4
    • /
    • 1999
  • The microstructure and magnetic properties of$ Fe_{87}Zr_7Si_4B_2$ nanocrystalline alloys were studied by magnetization measurements and M ssbauer spectrometry over a wide temperature range. Three well resolved spectral components have been found and attributed to bcc-Fe grains (with almost pure iron structure), residual amorphous matrix enriched with solute elements and interfaces formed at the grain-matrix boundaries. It has been shown that, contrary to the expectation, during crystallization the atomic segregation occurs leading to the formation of primary bcc-Fe grains and the partition of Si atoms into the residual amorphous matrix.

  • PDF

Improvement in the MIM Sintering Properties of 440C Stainless Steel

  • Soda, Yuji;Hurusaki, Takashi;Aihara, Michitaka
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09a
    • /
    • pp.217-218
    • /
    • 2006
  • More and more applications or demands for machine parts etc are expected for AISI 440C (hereinafter referred to as "440C") Stainless Steel because of its characteristic features, i.e. high-strength as well as high-corrosion resistance. This research has enabled us to obtain sintered products with good quality even under a wide range of temperature by utilizing the pinning effect of NbC, improving the relevant sintering feature of 440C Stainless Steel in the MIM method.

  • PDF

Components of a Comprehensive Transformer Monitoring and Diagnostic System (새로운 방식의 변압기)

  • Kim, Hyung-Seung;Kane, Claude
    • Proceedings of the KIEE Conference
    • /
    • 2007.07a
    • /
    • pp.97-98
    • /
    • 2007
  • A wide range of data is available as too causes of large power transformers. Although the percentage of transformer component failure rates vary, all data shows that the top three failure mechanisms are Load Tap Changers (LTC), Bushings and Windings. To date, the most common methods employed to determine the health of a transformer are off line tests and online temperature monitoring, winding hotspot calculations and dissolved gas analysis.

  • PDF

X-RAY DIFFUSE SCATTERINGS IN A Fe-Pt INVAR ALLOY

  • Ono, F.;Maeta, H.;Bang, L.
    • Journal of the Korean Magnetics Society
    • /
    • v.5 no.5
    • /
    • pp.354-357
    • /
    • 1995
  • Measurements of X-ray diffuse scatterings were made in disordered single crystal of Fe-28.3 at%Pt Invar alloy around a 200-Bragg peak in a wide temperature range between 15 K and 300 K. Observed diffuse scatterings were almost spherical, suggesting a homogeneous disordered alloy. However, the qdependence of the observed thermal diffuse scattering was different from the usual type, indicating a possibility of existence of local distortion of lattice accompanied by a large gradient of stress.

  • PDF

A Paradigm for the Viscosity of Fluids

  • Kim, Won-Soo;Chair, Tong-Seek;Pak, Hyung-Suk
    • Bulletin of the Korean Chemical Society
    • /
    • v.9 no.4
    • /
    • pp.213-217
    • /
    • 1988
  • A new paradigm for the viscosity of fluid is presented by considering the fact that the viscosity is equal to the shear stress divided by the shear rate. The shear stress is obtained from the sum of kinetic and internal pressures of fluid, and the shear rate is found from the phonon velocity divided by the mean free path of the phonon. The calculated viscosities for various simple substances are in excellent agreements with those of the observed data through the wide temperature range covered both of liquid and gas phase.

Theoretical Extinction Coefficients in ugriz

  • Han, Jiwon;An, Deokkeun;Lee, Young Sun
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.44 no.2
    • /
    • pp.67.4-67.4
    • /
    • 2019
  • We present extinction coefficients in the photometric filter system ugriz of the Sloan Digital Sky Survey, over a wide range of stellar properties based on theoretical stellar spectra generated using the ATLAS9 stellar models. Our computed coefficient values are essentially independent of a bulk metallicity or alpha-element abundance of a star, while they are a sensitive function of effective temperature and to a moderate extent of surface gravity of a star.

  • PDF

A Study on the ultrasonic signals analysis for scan fish schools and seabed targets (어군 및 해저 목표물 탐지를 위한 초음파 신호분석에 관한 연구)

  • Kim Jae-Gab;Kim Won-Jung;Yang Hwa-Sup;Jeong Chan-Ju
    • Management & Information Systems Review
    • /
    • v.2
    • /
    • pp.95-106
    • /
    • 1998
  • Color Echo-sounder display signals reflected from underwater objects in eight colors according to the strength of the signal. When the sea bottom is hard due to the presence of rocks, etc, the trailing on the reflection become strong signal and soft to presence of mud, etc the trailing on the reflection become weak signal. Strong signals are displayed in the color range, reddish brown, orange and yellow, in descending order of intensity. Weak signals are displayed in the range blue, light blue, cyan and green, in ascending order of intensity. Image of fish schools at or near the sea bottom vary according to the characteristics of the beam angle setting. When the angle is wide, even fish not near the bottom may be recorded as being on the seabed. A narrow angle should, therefore, be selected when you want to get an accurate recording of fish at or near the sea bottom. The condition of the sea bottom can be determinded more easily when the beam angle is wide and pulse with is long. Though the objects could be verified by the type of reflected signals which have been transformed into digital signals strong middle and weak ones, the experiments have in continue under various condition. Futhermore, the methode of measuring temperature inside the sea ought to be examined.

  • PDF