松尾山三社神社「松尾山御田植祭」於

松尾山三社神社上毛町松尾山三社神社傳承的「松尾山御田植祭」於18日舉行。
當天因下雨，活動改在町中央公民館支館實施。大批觀眾到場觀看，在眾人注目下，松會保存會以及町立友枝小學六年級的15名學生，表演了傳統舞蹈。
松尾山三社神社的主祭神之一即為市杵島姬命而與辯財天習合為同一柱女神~

月曜日のたわわ その５８４ 『お姉さんのおともだち』

月曜日のたわわ　その５８４　『お姉さんのおともだち』

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Electrodynamics Hydrodynamics quantum mechanics penetration depth

 

  These three quantities — the skin depth, the viscous penetration depth, and the thermal penetration depth — share the same mathematical structure.  Each describes how far an oscillatory disturbance can penetrate into a dissipative medium. In electromagnetics, the skin depth measures how deeply a time-harmonic field penetrates into a conductor.
  In fluid mechanics, the viscous penetration depth gives the thickness of the oscillatory viscous layer near a vibrating boundary.
  In heat transfer, the thermal penetration depth describes how far a periodic temperature variation can propagate into a medium. In all three cases, the penetration depth is determined by the competition between diffusivity and oscillation frequency, and scales as

《Physical Hydrodynamics》, §4.5.4 Oscillating flows in a viscous fluid

“ In Physical Hydrodynamics (§4.5.4), the oscillatory viscous boundary-layer problem is explicitly described as analogous to the skin effect in electrical conduction and to the penetration of seasonal temperature variations into the ground.”