Abstract: In an ultrasonic flow meter in which an ultrasonic transducer for transmission and an ultrasonic transducer for reception are arranged so as not to be opposite to each other, so that the flow rate is measured from the flow rate dependency of the phase difference of the ultrasonic wave in the fluid and the distance between said ultrasonic transducers, (1) the ultrasonic flow meter being provided with an oscillator wherein the frequency of the ultrasonic wave is controlled in correspondence with said phase difference in order to make it possible to measure when the phase difference is not smaller than 0-.pi., and (2) the ultrasonic flow meter also being provided with an electric circuit to compensate the measurement error due to the variance of the acoustic velocity of the ultrasonic wave in the fluid.

Abstract: Disclosed is an extraction method for optical character recognition systems in which the necessary character features for recognition process are extracted from a character information detected and digitized by an optical scanner. In accordance with this method, the local features of every adjacent two rows or columns of a digitized character pattern on a two-dimensional plane are extracted row by row or column by column and are successively integrated so as to extract in a global manner the respective feature types such as concavity and convexity, loop and connectivity of the character pattern. At the same time, the global feature regions or segments are separated and each of the separated feature segments is coded without any loss of the information. The feature quantity of each segment is obtained on the basis of the coded representation. Any local concavity or convexity noises are eliminated simultaneously with the extraction of the global features.

Abstract: A pressure control valve including a valve, a spring for pressing the valve, and a power input means for compressing the spring further comprises a backup force-generating mechanism for producing and directing a backup force counter to the direction in which the reaction force due to the compression of the spring is exerted on the input means, so as to impart the backup force to the input means.

Abstract: A nozzle flapper valve provided with a nozzle, fixed throttle and flapper, characterized in that the flapper is formed to be cylindrical and has the cylindrical peripheral surface positioned on the axis of the nozzle so as to simplify the flapper moving mechanism and to prevent the flapper clearance from being clogged with dust in the fluid.

Abstract: The present invention relates to an automatic steering apparatus for ships which prevents the occurrence of directional instability due to unusual phenomena which occur at small rudder angles of so-called full-bodied ships.When the rudder angle of such ship is small, two stable steady turning conditions occur so that the turning movement cannot assume any single state and it results in a frequent and irregular unstable ship motion.

Abstract: An automatic weld flaw detector comprises a comparator for comparing the height of an echo from a detected flaw upon movement of a probe over each unit distance with a maximum echo height already known, a counting circuit adapted to work in response to the comparing action of the comparator so as to determine the distance the probe has covered, a device adapted to be actuated by the output from the comparator thereby to memorize separately the maximum value of echo height and the output at that moment from the counting circuit, and a recorder connected to the memorizing device.

Abstract: In an output control device for a hydraulic pump of the variable displacement type wherein delivery pressure is led into a cylinder of the control device to move a control piston therein back and forth and let the piston change the inclination of a yoke, thereby varying the delivery of the pump, the improvement comprising a cam formed on a piston rod directly connected to the control piston, a hollow cylindrical sleeve slidable in the direction at right angles to the piston rod and adapted to remain in sliding contact with the cam so that, with the displacement of the control piston due to a rise of fluid pressure, the sleeve can be displaced by the cam away from the piston rod, said sleeve having a pressure pickup hole communicated with a fluid passage leading to the cylinder, a compensator piston slidably fitted in the sleeve and adapted to close the pressure pickup hole and shut off the flow of pressure fluid into the cylinder when the fluid pressure is zero and be moved, with the rise of fluid pressure, a