An experimental procedure for studying soliton gases in shallow water is devised. Nonlinear waves propagate at constant depth in a 34\,m-long wave flume. At one end of the flume, the waves are generated by a piston-type wave-maker. The opposite end is a vertical wall. Wave interactions are recorded with a video system using seven side-looking cameras with a pixel resolution of 1\,mm, covering 14\,m of the flume. The accuracy in the detection of the water surface elevation is shown to be better than 0.1 mm. A continuous monochromatic forcing can lead to a random state such as a soliton gas. The measured wave field is separated into right- and left-propagating waves in the Radon space and solitary pulses are identified as solitons of KdV or Rayleigh types. Both weak and strong interactions of solitons are detected. These interactions induce phase shifts that constitute the seminal mechanism for disorganization and soliton gas formation.

中文翻译：

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用大规模视频波测量分析孤子气体

设计了研究浅水中孤子气体的实验程序。非线性波在 34 米长的波槽中以恒定深度传播。在水槽的一端，波浪由活塞式造波器产生。另一端是一堵垂直的墙。波相互作用通过视频系统使用七个像素分辨率为 1\,mm 的侧视摄像机记录，覆盖水槽的 14\,m。水面高程检测精度优于0.1mm。连续的单色强迫会导致随机状态，例如孤子气体。测量的波场在氡空间中被分为右向和左向传播波，孤立脉冲被识别为 KdV 或瑞利型孤子。检测到孤子的弱相互作用和强相互作用。