Array ( [0] => Array ( [title] => L21A [link] => https://www.youtube.com/embed/i9vdpMgFXKY ) [1] => Array ( [title] => L21B [link] => https://www.youtube.com/embed/iVpnVr7NOjc ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - Lecture 21 | Example: Planar Hopf bifurcation; Example: Takens-Bogdanov bifurcation