A method for managing a memory of a computer system to store a data of a first size, comprising the steps of defining chunks of the memory, wherein each chunk is a continuous memory space of a predetermined size. The function of such a hydraulic valve arrangement should be enhanced. The anti-abnormal type prion monoclonal antibody of the invention may be obtained by immunizing an animal with an immunogen including a peptide containing a plurality of regions in the abnormal type prion, which regions are discontinuous each other in primary amino acid sequence of the abnormal type prion. Several devices are described and employ either fixed effects of the element that are combined with variable nonreciprocal effects, or the reverse. A control block receives the estimated rotation angle and the estimated speed from the estimation unit, and outputs the reference magnetic flux voltage and the reference torque voltage of the motor to the rotationfixed coordinates converter to compensate an error caused by loads generated when driving the motor. The recessed portion may have a recessed face.