Abstract: A visible light transmitting signal is modulated on the basis of an information signal to be transmitted, and is superimposed on a visible light to be transmitted. A camera (10) photographs the transmitted visible light by use of a pixel amplifier sequential output type imaging element (11), and the pixel amplifier sequential output type imaging element (11) amplifies electric charges generated in respective pixels by respective pixel amplifiers (22), to output imaging signals in sequence from the respective pixel amplifiers (22). Image data of light and dark bands acquired from the imaging signals are taken in by frame, and a differential value is calculated for displacement of exposure amounts of the respective pixels output in sequence or the respective rows. The transmitted information signal is demodulated on the basis of the differential value of the imaging signals of a plurality of samples serving respective pixels or respective rows as one sample in one frame.

Abstract: A visible light transmitting signal is modulated on the basis of an information signal to be transmitted, and is superimposed on a visible light to be transmitted. A camera (10) photographs the transmitted visible light by use of a pixel amplifier sequential output type imaging element (11), and the pixel amplifier sequential output type imaging element (11) amplifies electric charges generated in respective pixels by respective pixel amplifiers (22), to output imaging signals in sequence from the respective pixel amplifiers (22). Image data of light and dark bands acquired from the imaging signals are taken in by frame, and a differential value is calculated for displacement of exposure amounts of the respective pixels output in sequence or the respective rows. The transmitted information signal is demodulated on the basis of the differential value of the imaging signals of a plurality of samples serving respective pixels or respective rows as one sample in one frame.

Abstract: A visible light is photographed through an optical diffusion filter with a camera of a portable terminal. The camera includes a pixel amplifier sequential output type imaging element in which electric charges generated in respective pixels are amplified by respective pixel amplifiers, to output imaging signals in sequence from the respective pixel amplifiers. A striped pattern based on an information signal is generated in the column direction or row direction in the imaging element, in a photographed optically-diffused image. The information signal is extracted to be demodulated on the basis of a state of generation of the striped pattern.

Abstract: A visible light is photographed through an optical diffusion filter with a camera of a portable terminal. The camera includes a pixel amplifier sequential output type imaging element in which electric charges generated in respective pixels are amplified by respective pixel amplifiers, to output imaging signals in sequence from the respective pixel amplifiers. A striped pattern based on an information signal is generated in the column direction or row direction in the imaging element, in a photographed optically-diffused image. The information signal is extracted to be demodulated on the basis of a state of generation of the striped pattern.

Abstract: In the present invention, testing is performed by injecting grout (G) into a full-scale specimen comprising a cable that is fabricated at a place other than a construction site. The cable has a sheath made of a transparent material and has the same three-dimensional configuration as that of an internal cable (2°) at the construction site. Alternatively, grout (G) is injected into a partial specimen comprising a lengthwise part of the cable where an air trap is likely to occur. The testing is performed under a plurality of different testing conditions. The best grouting conditions are selected from testing results and applied to grouting actually carried out at the construction site.

Abstract: A PC strand is formed by twisting peripheral wires made of deformed PC steel wires around a core, and allowing rust inhibitive material of thermoplastic resin to permeate into voids defined among the core and peripheral wires by use of an extruder. Since at least one of the core and peripheral wires is made of a deformed PC steel wire having an uneven outer surface, the thermoplastic resin can smoothly permeate deep into the inside of the PC strand.

Abstract: A reinforcement binding machine using a steel wire comprises a means for feeding the steel wire into a binding station for binding reinforcements together, a guide means provided with a guide path for guiding the steel wire fed into the binding station along a curve encircling the reinforcements and defining the binding station, a means for twisting the steel wire looped by the guide path and defining a slot through which the steel wire fed into the binding station is capable of passing, and a means for rotating the twisting means about the axis crossing the axis of the loop formed from the steel wire so as to twist the steel wire, the twisting means being provided with a pair of pins opposed to each other through the slot and adapted to be moved relatively in the axial direction with respect to the loop, and a means for normally biasing at least one of the pins toward the other one of the pins such that the end faces of the pins are abutted against each other within the binding station.