Stringed instrument, especially the guitar with flexible connection of the upper part of the heel of the neck below the fingerboard to the fixing block in the body of the instrument, whereby the lower free end of the heel of the neck is coupled to a fixing block in the body of a stringed instrument through the rod via a rectification element which dilates in reaction to atmospheric humidity changes.

A multi-dimensional precision spot inspection method and system for thermal power equipment, and the method includes: determine the equipment requiring precision spot inspection and the initial test period of the equipment to be inspected; acquire the historical precision spot inspection information of the equipment to be inspected, adjust the initial test period of the equipment to be inspected according to the historical precision spot inspection information, and obtain the first test period; perform the precise spot inspection on the equipment to be inspected according to the first test period, obtain the precision spot inspection result within the first test period, and adjust the first test period to obtain the second test period when the precision spot inspection result is more than or equal to the standard value. In the invention, the test period of the thermal power equipment is adjusted, effectively improving the effectiveness and accuracy of the test period.