Abstract: A lighting device in which an amount of light emitted by a lamp is detected by a light receiving element for controlling the input voltage of the lamp commensurate with the detected amount of light. By utilizing a pre-illumination system in conjunction with the lighting device, it is possible to improve the sensitivity characteristics of the light receiving element as the lamp is being charged up to a desired level of illuminescence and to prevent the input of an excessive voltage to the lamp.

Abstract: An output amplifying circuit which comprises a Push Pull amplifier section, a power supply circuit section and an amplifier section for amplifying a power source. The circuit eliminates an occurrence of switching distortion and minimizes heat loss therein. The input terminals of the Push Pull amplifier section and the power source amplifier section are connected in common, while the positive and the negative terminals of the power source amplifier section are connected to those of the power supply circuit section, respectively.

Abstract: A single sideband receiver having a demodulator or mixer for carrier frequency demodulation in response to the output of a controllable variable frequency oscillator and an intermediate frequency demodulator for providing a demodulated signal is provided with an automatic frequency control system comprising a low pass filter for separating a low frequency portion from the demodulated signal a discriminator for detecting the level of the low frequency portion with respect to a predetermined level, and a circuit for controlling the frequency of the variable frequency oscillator in response to the detected relationship between the low frequency portion and the predetermined level.

Abstract: The response time of an ordinary or differential transistor switching circuit controlled by the charging of a capacitor C.sub.1 is shortened by rapidly charging the capacitor through a transistor Q.sub.6 connected in parallel with the charging resistor R.sub.1 of the capacitor. The transistor is rendered conductive before the differential switching region is reached in response to the capacitor charge reaching a predetermined level, whereby the charging curve thereafter follows a steep rise to sharply reduce the switching time.

Abstract: The response time of an ordinary or differential transistor switching circuit controlled by the charging of a capacitor C.sub.1 is shortened by charging the capacitor through a constant current source comprising a transistor Q.sub.6, a resistor R.sub.1 and diodes D.sub.1, D.sub.2, to thereby provide a sharp transfer characteristic. The charging time may be even further shortened by increasing the constant current supply at an intermediate threshold level using a further ordinary or differential transistor switching circuit, thereby providing a break in the response characteristic and increasing its slope after the threshold point.

Abstract: A circuit for detecting a DC signal in the output of an audio amplifier 1 and for uncoupling a speaker SP in response thereto comprises a low-pass filter 2 whose output is coupled to one input of differential amplifiers 5, 6 whose other inputs are unbalanced by respective positive and negative threshold biasing potentials E.sub.1, E.sub.2. The differential amplifiers are directly connected to respective current mirror circuits 7, 8, and their high impedance side collector outputs are applied to the inputs of an OR circuit whose output in turn controls the speaker uncoupling.

Abstract: A water intake portion of a hydraulic machine consists of a casing and a speed ring positioned between the casing and guide vanes for guiding water from the casing to the guide vanes. The speed ring consists of a pair of upper and lower flat members of a ring form, a plurality of stay vanes positioned between the aforesaid pair of members for interconnecting same rigidly, and a reinforcing member of a cylindrical form, which is welded to the top surface of the upper flat member between the inner and outer circumferential edges of the upper flat member. Edges defining therebetween an opening of this casing are welded to the top surface of the upper flat member of a ring form, of the speed ring in the position between the aforesaid reinforcing member and the outer circumferential edge of the upper flat member, as well as to the undersurface of the lower flat member of a ring form, respectively.

Abstract: Conductive caps are respectively put on both ends of an insulating cylindrical member and a pair of cup-shaped contactors are disposed in the insulating cylindrical member in a manner to be movable relative to each other. A repulsive force is provided by a pair of biasing elements located between the pair of cup-shaped contactors through a fusible member to electrically interconnect the conductive caps. When the fusible member is fused at a predetermined temperature, the biasing force of one of the biasing elements weakens and the biasing force of the other biasing element increases to move the pair of cup-shaped contactors toward each other, thereby to electrically disconnect the conductive caps from each other.

Abstract: Method of controlling fungal diseases in plants and Compositions effective therefor are shown. The method comprises the steps of applying an effective amount of a substituted derivative of 1,1,-dichloroalkene-1 of the general formulaR--X--(CH.sub.2).sub.n --CH.dbd.CCl.sub.2In this generalized formula R is an alkyl group having 1 to 12 carbon atoms, a phenyl group, a di-chloro-phenyl group, a methyl-phenyl group, a nitro-phenyl group, a benzyl group, a chloro-benzyl group, a di-chloro-benzyl group, a methyl-benzyl group, a phenethyl group or a benzothiazolyl group; X is sulfur, a sulfinyl group or a sulfonyl group; and n is an integer of 3,5, and 7.

Abstract: New substituted derivatives of 1,1-dichloroalkene-1 of the general formula:R--X--(CH.sub.2).sub.n --CH.dbd.CCl.sub.2in which R is one of an alkyl group and particularly an alkyl group of 1 to 12 carbon atoms, a phenyl group, chloro-phenyl group, dichloro-phenyl group, methyl-phenyl group, nitro-phenyl group, benzyl group, chloro-benzyl group, dichloro-benzyl group, methyl-benzyl group, phenetyl group and benzothiazolyl group; X is one of a sulfur atom a sulfinyl group and sulfonyl group; and n is an integer of 3,5 and 7.

Abstract: An object disposed in a fluid flow and defined by two surfaces, each extending along a stream line and one of said two surfaces having a reference contour. To eliminate the danger that a violent oscillation is generated due to resonance between the natural oscillation of the object and the oscillation caused by Karman's vortex which develops at the downstream end portion of the object, said downstream end portion of the object is so formed as to provide a configuration satisfying the following relations:R1/TV.ltoreq.0.2 and R2/TV=6-10where, R1 is a radius of curvature of the first portion of object's downstream end portion which is continuous with said reference surface, R2 is a radius of curvature of the second portion of object's downstream end portion extending between said first portion and the other surface, and TV is the minimum thickness of the object between said two surfaces measured from the joining point or juncture between said second portion and the other surface.