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Part I – Basics (1) Geometric model: - interconnected model elements

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1 Part I – Basics (1) Geometric model: - interconnected model elements
(2) DOFs of a geometric model (3) FBDs of model elements (4) Elemental equations (5) Energy storage and dissipation (6) Obtain model parameters (7) Obtain simplified equivalent systems hw1~hw4. Also, examples in notes.

2 Part II – SDOF systems 2.1 Free vibration of undamped system
(1) Obtain math model (hw4) π‘Ž 2 𝑦 + π‘Ž π‘œ 𝑦=0 (2) Solution for the vibration (hw5) (3) System property and application (hw5) - the natural frequency: Examples in notes.

3 2.2 Free vibration of damped system (1) Obtain math model (hw6)
π‘Ž 2 𝑦 + π‘Ž 1 𝑦 + π‘Ž π‘œ 𝑦=0 or 𝑦 +2πœ‰ πœ” 𝑛 𝑦 + πœ” 𝑛 2 𝑦=0 πœ” 𝑛 = π‘Ž π‘œ / π‘Ž and πœ‰= 1 2 πœ” 𝑛 π‘Ž 1 π‘Ž 2 (2) Solution for the vibration (hw7) underdamped: 𝑦 𝑑 =𝐴 𝑒 βˆ’πœ‰ πœ” 𝑛 𝑑 sin( πœ” 𝑑 𝑑+πœ™) critically damped: 𝑦 𝑑 = (𝐴 1 + 𝐴 2 𝑑) 𝑒 βˆ’ πœ” 𝑛 𝑑 overdamped: 𝑦 𝑑 = 𝐴 1 𝑒 𝑠 1 𝑑 + 𝐴 2 𝑒 𝑠 2 𝑑 (3) System property and application (hw7) For underdamped systems: πœ” 𝑛 , πœ‰ ~( 𝑇 𝑑 , 𝛿) relations

4 2.3 Harmonically excited vibration
(1) Obtain math model (hw8) π‘Ž 2 𝑦 + π‘Ž 1 𝑦 + π‘Ž π‘œ 𝑦=β„Ž(𝑑) or 𝑦 +2πœ‰ πœ” 𝑛 𝑦 + πœ” 𝑛 2 𝑦=πΈπ‘ π‘–π‘›πœ”π‘‘ (2) Solution for the vibration (hw8) 𝑦 𝑑 = 𝑦 β„Ž 𝑑 + 𝑦 𝑝 (𝑑) 𝑦 β„Ž (𝑑) same expression as 𝑦(𝑑) in 2.2, different 𝐴 1 , 𝐴 2 𝑦 𝑝 𝑑 =π‘Œπ‘ π‘–π‘›(πœ”π‘‘+πœ“) Y by Eq. (M): π‘Œ= 𝐸/ πœ” 𝑛 (1βˆ’ π‘Ÿ 2 ) 2 + (2πœ‰π‘Ÿ) 2 1/2 πœ“ by Eq. (P): πœ“=βˆ’ π‘‘π‘Žπ‘› 2 βˆ’1 2πœ‰π‘Ÿ 1βˆ’ π‘Ÿ 2 (3) Application (hw9) π‘Œ,πœ“ ~ 𝐸, πœ” ~( πœ” 𝑛 , πœ‰) relations


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