Update README.md

Author: XiongWeiTHU

README.md

@@ -1,5 +1,5 @@
 <h1 align="center">
-<img src="/logo.png" width="700">
+<img src="https://github.com/Koopman-Laboratory/KoopmanLab/blob/main/logo.png" width="700">
 </h1><br>
 
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