Abstract: An electronic signal representative of a sound is processed by applying different amplitude adjustments to the different components of the signal, these amplitude adjustments vary with frequency in a manner corresponding to the variation with frequency of the auditory response of a normal human listener for sounds impinging on him from a preselected direction of perception. When the electronic signal is converted into sound, the relationship of the amplitudes of the various components of the signal causes the listener to believe that the sound is impinging on him from the preselected direction.

Abstract: Apparatus for simultaneously pinching a plurality of elongated bags disposed in parallel, side by side relation with one another and transferring the bags. The apparatus includes a gripper mechanism arranged to pinch each bag at two longitudinally spaced locations thereon and devices for moving the gripper mechanism while the bags are pinchingly thereby. Sensing devices are provided to detect the state of pinched engagement of the bags with the gripper mechanism. If one or more of the bags is not pinched or is improperly pinched by the gripper mechanism, the transfer motion is arrested to prevent damage to the bag or the apparatus. The apparatus can be utilized to remove paper bags containing stacks of metal can lids from boxes.

Abstract: A crib unit of heavy, rugged character and which is useable in erecting bin wall structures for various purposes such as sea walls, retaining walls, etc. The unit has a pair of spaced side walls with a connector arm extending between the side walls and joined thereto with merger segments, the merger segments being of laterally widening character to effect strengthening of the side walls to render same more resistive to bending. The crib unit when paired with a like unit encloses a bin space having a configuration which facilitates substantially uniformly distributing bin fill pressure acting against the crib unit structure defining the bin.

Abstract: A calcium aluminum fluorosilicate glass powder is disclosed which has average particle size of at least 0.5 microns, and is characterized in that the calcium in the surface of the powder's particles is depleted so that the quotient of the atomic ratio Si/Ca at the surface of the particles and the atomic ratio Si/Ca in the core region of the particles is at least 2.0, more preferably at least 3.0 and most preferably at least 4.0. The glass powder may be prepared by surface treating calcium aluminum fluorosilicate glass powder particles with an acid which forms calcium salts, washing the calcium salts off the treated particles and drying the washed particles.The glass powder has utility in self-hardening glass ionomer cements, such as dental or bone cements. Cements formed from the glass powder exhibit reduced periods of water sensitivity, while permitting sufficient time for processing.