A downhole tool system includes a downhole tool operably positionable within a wellbore and a sensor positioned within the downhole tool. A circuit-mounting structure is disposed between the crank axle mounting portion and the pedal mounting portion, wherein the circuit-mounting structure is configured to detachably mount a measurement board. The outline image is drawn with a thicker outline when an angle \u03b8 between a first vector extending from a point on the face toward the viewpoint and a normal vector changes from the right angle with a lower decrement, and drawn with a thinner outline line when the angle \u03b8 changes from the right angle with a higher decrement. Third, repeat the procedure mention above for a plurality of modems to get a plurality of sampling data tables respectively, and then obtain a mean data table.