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           __   __               ___       _____  
  ____     \ \\/ //     ___     / _ \\    / ___// 
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 |  __//     |_||      \__ ||   \___//   /____//  
 |_|`-`      `-`'       -|_||   `---`   `-----`   
 `-`                     `-`

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Text this: Utilization of standing waves to improve effectiveness of noise barriers