發送短信 : Secure detection : performance metric and sensor deployment strategy

  _  _     ______  __    __     ___      _  __  
 | \| ||  /_   _// \ \\ / //   / _ \\   | |/ // 
 |  ' ||   -| ||-   \ \/ //   | / \ ||  | ' //  
 | .  ||   _| ||_    \  //    | \_/ ||  | . \\  
 |_|\_||  /_____//    \//      \___//   |_|\_\\ 
 `-` -`   `-----`      `       `---`    `-` --`