Abstract: Provided is a pedo-transfer function (PTF)-based method for predicting a target soil property. Based on the collection of a multi-source soil dataset and environmental variables, a dataset containing all measured information is divided. Second-level regions are obtained by zoning according to the spatial variation in soil properties. An optimal independent variable set of PTFs in different regions is obtained by screening. Then, linear fitting and nonlinear fitting of the PTFs are performed for different zones separately. By comparing the accuracy of different functions between different zones, optimal PTFs oriented toward sampling sites are selected, so as to build a database including soil sampling sites. Further, regional independent variable layers are constructed by means of machine learning, to establish region-oriented PTFs; and a spatial distribution map of the target soil property and content for a target region is produced.

Abstract: A power connector includes a housing and a clamp group disposed in the housing. An insertion opening is formed at one end of the housing, and the insertion opening is configured to plug in a plug. The clamp group includes an inner clamp and an outer clamp. An insertion slot is formed in the inner clamp, and the insertion slot is opposite to the insertion opening and is configured to accommodate a front end portion of the plug. The outer clamp is disposed to extend over the inner clamp. When the plug passes through the insertion opening and is plugged into the insertion slot, a contact end of the outer clamp close to the insertion opening presses against a conductive surface of the plug. A contact segment of the inner clamp also presses against the conductive surface of the plug.

Abstract: Provided is a pedo-transfer function (PTF)-based method for predicting a target soil property. Based on the collection of a multi-source soil dataset and environmental variables, a dataset containing all measured information is divided. Second-level regions are obtained by zoning according to the spatial variation in soil properties. An optimal independent variable set of PTFs in different regions is obtained by screening. Then, linear fitting and nonlinear fitting of the PTFs are performed for different zones separately. By comparing the accuracy of different functions between different zones, optimal PTFs oriented toward sampling sites are selected, so as to build a database including soil sampling sites. Further, regional independent variable layers are constructed by means of machine learning, to establish region-oriented PTFs; and a spatial distribution map of the target soil property and content for a target region is produced.

Abstract: A power connector includes a housing and a clamp group disposed in the housing. An insertion opening is formed at one end of the housing, and the insertion opening is configured to plug in a plug. The clamp group includes an inner clamp and an outer clamp. An insertion slot is formed in the inner clamp, and the insertion slot is opposite to the insertion opening and is configured to accommodate a front end portion of the plug. The outer clamp is disposed to extend over the inner clamp. When the plug passes through the insertion opening and is plugged into the insertion slot, a contact end of the outer clamp close to the insertion opening presses against a conductive surface of the plug. A contact segment of the inner clamp also presses against the conductive surface of the plug.