Methods of adjusting a velocity at which a drill string is moved within a well are provided. These solenoid valves are arranged with their respective bodies interconnected in a side-by-side arrangement, with the inlet ducts parallel with one another and with their respective windings also parallel with one another. By determining the rising sharpness of the peak and waveform distortion in the sphygmographic waveform, determination is made whether the pressurization force of the cuff is appropriate or not to carry out further adjustment of pressure, as necessary.