Download the applet file (click get files for offline use)and upload it to your web site.

Or add the following code directly:
<applet code="Doppler.class" width=600 height=340 codebase="http://www.phy.ntnu.edu.tw/java/Doppler/"><param name="Reset" value="Reset"><param name="Start" value="Start"><param name="Time" value="Time="><param name="waveSpeed" value="wave  speed "><param name="sourceSpeed" value="source speed "><param name="wavelength" value="wave length "></applet>

You can change  values in the above tags to translate it to your own format (different language translation) and the string in the applet will be changed to supplied value.