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

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Text this: 最小安全间距约束下拥挤交通流速度-密度关系模型 = Speed-density relation model of congested traffic flow under minimum safety distance constraint