摘要
The gradient descent(GD)method is used to fit the measured data(i.e.,the laser grain-size distribution of the sediments)with a sum of four weighted lognormal functions.The method is calibrated by a series of ideal numerical experiments.The numerical results indicate that the GD method not only is easy to operate but also could effectively optimize the parameters of the fitting function with the error decreasing steadily.The method is applied to numerical partitioning of laser grain-size components of a series of Garzêloess samples and three bottom sedimentary samples of submarine turbidity currents modeled in an open channel laboratory flume.The overall fitting results are satisfactory.As a new approach of data fitting,the GD method could also be adapted to solve other optimization problems.
The gradient descent（GD） method is used to fit the measured data（i.e., the laser grain-size distribution of the sediments） with a sum of four weighted lognormal functions. The method is calibrated by a series of ideal numerical experiments. The numerical results indicate that the GD method not only is easy to operate but also could effectively optimize the parameters of the fitting function with the error decreasing steadily. The method is applied to numerical partitioning of laser grain-size components of a series of Garzê loess samples and three bottom sedimentary samples of submarine turbidity currents modeled in an open channel laboratory flume. The overall fitting results are satisfactory. As a new approach of data fitting, the GD method could also be adapted to solve other optimization problems.
基金
supported by the National Natural Science Foundation of China(Grant Nos.41072176,41371496)
the National Science and Technology Supporting Program of China(Grant No.2013BAK05B04)
the Fundamental Research Funds for the Central Universities(Grant No.201261006)
