發送短信 : Magnetic field of tubular linear machines with dual Halbach array

            ______   ______    _    _      _____  
    ___    /_   _// |      \\ | || | ||   / ___// 
   /   ||   -| ||-  |  --  // | || | ||   \___ \\ 
  | [] ||   _| ||_  |  --  \\ | \\_/ ||   /    // 
   \__ ||  /_____// |______//  \____//   /____//  
    -|_||  `-----`  `------`    `---`   `-----`   
     `-`