Tottori University

Tottori University Research Result Repository
Not a member yet
    9510 research outputs found

    Kinetic theory analysis of microscale lubrication of a gas between eccentric circular cylinders with an arbitrary temperature difference

    Get PDF
    A microscale lubrication flow of a gas between eccentric circular cylinders with an arbitrary temperature difference is studied on the basis of kinetic theory. The dimensionless curvature, defined as the mean clearance divided by the radius of the inner cylinder, is small, whereas the temperature ratio and the Knudsen number based on the mean clearance take arbitrary values. The Bhatnagar–Gross–Krook–Welander (BGKW) model of the Boltzmann equation in bipolar coordinates is studied analytically using the slowly varying approximation. The leading-order term of the perturbation, which ought to be the solution of the nonlinear heat transfer problem, is replaced by the free molecular solution or an equilibrium solution at rest. Two macroscopic lubrication models are derived, along with a numerical database that enables one to use the models quickly. Direct numerical analysis of the BGKW equation is also conducted, and the validity of the lubrication models is assessed. The heating of either cylinder enhances both the eccentric force and the torque acting on the inner cylinder. When the Knudsen number is small, there is little difference in the eccentric force between the cases in which the rotating inner cylinder is heated and the stationary outer cylinder is heated. However, this difference becomes significant as the Knudsen number increases, with heating of the outer cylinder yielding the greater eccentric force. If the two lubrication models are applied complementarily depending on the Knudsen number, they provide a reasonable result for the eccentric force over a wide range of the Knudsen number

    ガッコウ キボ ポジティブ コウドウ シエン ガ キョウシ ノ メンタルヘルス ニ オヨボス エイキョウ

    Get PDF
    本研究では,学校規模ポジティブ行動支援(SWPBS)の実施が教師のメンタルヘルスと教師間コミュニケーションに与える影響について検討した。SWPBS 実施校と非実施校の教師 88 名を対象に,仕事の負担感,教師同士のつながり,バーンアウト,自己効力感を比較した。また,SWPBS 実施校に対して,SWPBS の効果についての満足度および SWPBS 実施に伴う教師間コミュニケーションの変化について自由記述のアンケートを実施した。結果,SWPBS 実施校の方が非実施校よりも仕事の負担感の評価指標の 1 つである平均残業時間が短いことが明らかになった。一方で,仕事の負担感,教師同士のつながり,教師バーンアウト,教師自己効力感に有意な差は認められなかった。ただし,SWPBS 実施校において,約 9 割の教師が SWPBS の効果を評価していた。また,児童の良い行動の共有が増えたなど,約半数が教師間コミュニケーションの良い変化を実感していた

    6,860

    full texts

    9,510

    metadata records
    Updated in last 30 days.
    Tottori University Research Result Repository
    Access Repository Dashboard
    Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇