The behavior of a group of resources, such as a fleet of servers, can be monitored to attempt to determine a baseline of acceptable behaviors. The methods can include positioning a toolstring in a wellbore. This method is particularly useful for reclaiming and reusing solvents that are used in the development or chemical washout of flexographic printing plates. Either the gain controlled signal by the analog PGA 4 or the signal sent from the changeover switch 3 is selected by a changeover switch 5. The mounting module of the magnetic mechanism is fixedly mounted on a fixed part of a bicycle close to a wheel thereof, and the connecting module of the coil module is fixedly connected to two spokes of the wheel, such that the magnetic element assembly and the coil assembly are located at corresponding radial positions relative to the wheel.