In a front fork in a two-wheeled vehicle or motor vehicle, a partition wall member sectioning an oil reservoir chamber into upper end lower sides is provided in an upper portion of a hollow pipe. The motion controller includes a target position generator, a sliding mode controller, a disturbance observer and a state observer. The elevating space and the storage space are arranged in a direction orthogonal to the running rail, as viewed from above. The field addition circuit is configured to perform a field addition on the data in the prime field in response to the instructions requiring the field addition. The reaction mixture resulting from oxidative direct carbonylation contains in addition to and, at least one hydroxyaromatic compound and at least one reaction product and optionally a solvent, and the process entails.