ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

Soil thickness is an important parameter affecting soil quality. Rapid acquisition of accurate soil thickness information is an important data basis for the analysis and evaluation of the quality of cultivated land resources and its changing trend. Current mainstream measurement methods are inefficient or inaccurate, such as radar detection method and borehole sampling method. The rapid measurement of soil thickness was realized based on soil mechanical resistance with optimized cone meter. Data were acquired by a cone soil thickness measuring instrument which was an optimized handheld cone meter attached with acceleration sensor, position sensor and other sensors. Acceleration compensation technology was adopted to reduce the measurement error of soil mechanical resistance caused by nonuniform speed penetration of cone meter. Envelope detection and Hilbert instantaneous amplitude eigenvalue clustering algorithm were introduced to identify soil structure and calculate the thickness of soil layer. The simulation results based on Ayers semiempirical model showed that the conical soil thickness measuring instrument based on Hilbert transform algorithm can effectively acquire the information of soil thickness with relative error no higher than 7.50%. The measuring results for outdoor measured data showed that the absolute error of soil thickness measured by Hilbert instantaneous amplitude spectrum based on lower envelope was not more than 1cm, and the relative error was not more than 10%. This method can meet the needs of actual measurement for plough layer soil depth and provide a reference for future soil layer measuring application.