A device for measuring reverberation characteristics in a reverberation room by a digital squaring and integrating computation process. According to the invention, only a part of digital data of a large word length obtained by squaring and integrating a reverberation signal is selected out for computing the reverberation characteristics in accordance with a measuring environment such as integration time and duration of a test pulse. By this arrangement, circuitry for computing the reverberation ...

Polycarbonate copolymers from bisphenol-A containing terephthalate moieties constituting 5 or 10 mol percent of the polymer, whereby after long exposure to working temperature the polymer retains Izod impact resistance of at least 9 ft. -lbs. per inch of notch.

A fast and reliable method is disclosed for measuring the dynamic mechanical properties of a material, particularly its modulus of elasticity and loss factor. By this method the acoustic characteristics of a material can be determined. An elongate strip of material, whose properties are desired to be known, is provided with miniature accelerometers fixedly secured to its opposite ends. One end of the strip is excited by a random noise source which travels toward the other end where that end and ...

A device for measuring semiconductor characteristics, wherein electrodes are installed maintaining a gap on the front and back sides of a semiconductor specimen of which the characteristics are to be measured, at least one of the electrodes being transparent, the surface of the semiconductor specimen is scanned with a pulsed narrow photon beam via the transparent electrode, and a photovoltage generated between the front and back surfaces of the semiconductor specimen is taken out from the two el...

In a multifilamentary superconductor, plural filaments are separated from one another by a ductile nonsuperconducting copper matrix. The niobium titanium filaments are arrayed through the copper, with one filament being substantially larger than the others, and preferably, centrally located in the wire. Preferably also, the other filaments are arrayed in an annular configuration about the periphery of the wire.

A novel digitized measuring system is disclosed for the measurement of the DC parameters of a wide variety of electrical and electronic devices. A stimulus measuring unit (SMU) is disclosed which can alternatively act as a voltage source and current monitor or as a current source and voltage monitor. A device under test (DUT) can be characterized without changing external connections and the resulting data can be manipulated and displayed in a wide variety of graphical or tabular forms.

A variable characteristics amplifier circuit such as may be used in an inter-music interval detecting circuit for a tape deck, record player, or the like. First and second transistors are connected in an emitter follower configuration with an input signal being applied to the base of the first transistor. One of the emitter or collector of the second transistor is connected through a series circuit of a capacitor and resistor to an inverting input terminal of an operational amplifier, and a feed...

A method and apparatus provide for the bleaching of mechanical pulp in such a way that the brightness of the mechanical pulp can be increased up to about 7-10 points. Mechanical pulp directly from a secondary refiner is separated, as by first and second centrifugal separators (cyclones), into a fines fraction and a fiber fraction. The fines fraction is under about 200 mesh. The fiber fraction is mixed with hydrogen peroxide (H.sub.2 O.sub.2) and subjected to displacement bleaching, which uses a ...

In a method for providing musical accompaniment in response to playing of a processor-controlled musical instrument, a plurality of processes corresponding to different musical components of the accompaniment are executed in a pseudo-concurrent manner. Each component includes a plurality of musical events related according to a tempo at which the accompaniment is to be sounded. A portion of one of the processes is executed to perform at least one of the musical events, whereupon the process is s...

In apparatus for removing water and impurity components from sand, there are provided a rotary member having an opening at one end for charging and discharging sand and a filter for passing water. The rotary member is supported by a support and driven by a variable speed motor. Piston-cylinders or the like are provided for tilting the support. In a modified embodiment, two of the rotary bodies are juxtaposed with their openings faced each other. A peripheral wall of the rotary member is provided...