Abstract: A transmission method including the steps of: dividing an input video signal into a plurality of packets which comply with a predetermined transmission standard and preferentially selecting, as a transmission path for each of the plurality of packets, a transmission channel, to which a lower frequency band is allocated, from among the plurality of transmission channels which are allocated along a frequency axis; and modulating, by using a multicarrier modulation method, the plurality of packets and transmitting the modulated packets to a receiving device along a cable through the selected transmission channel, the cable having a transmission characteristic such that attenuation of a signal to be transmitted increases with the frequency of the signal.

Abstract: A method for measuring shear load of a fastening tool, which comprises the steps of: positioning an optical fiber sensor on a surface of a fastening tool to be subjected to a measurement, or within the tool but near the surface thereof, so that the optical fiber sensor is positioned along a direction of an axis the fastening tool; and measuring the shear load acting on the fastening tool on the basis of a change in an optical characteristic of the optical fiber sensor that directly corresponds to a deformation of the fastening tool when the shear load is applied to the fastening tool.

Abstract: A method is disclosed wherein a portion of a sensor part of an optical fiber sensor is embedded in an adhesive between two joined members, and peeling in an adhesive joint of the two members is detected on the basis of measuring optical characteristics from the optical fiber sensor when the optical fiber sensor is irradiated with light from a light source while one member is vibrated by vibration means. The method comprises the steps of determining the temperature of the two members during measurement on the basis of the optical characteristics from the sensor part exposed outside of the adhesive; determining, on the basis of the temperature determined during the measurement, the measurement range in which the optical characteristics from the optical fiber sensor are measured; and measuring the variation in the optical characteristics from the optical fiber sensor within the determined measurement range while the member is being vibrated by the vibration means.

Abstract: A digital signal transmission apparatus that transmits a digital signal to another apparatus via a coaxial cable connected therebetween includes a signal divider configured to divide a digital signal to be transmitted into a plurality of signal groups; a plurality of modulators configured to modulate each of the plurality of signal groups obtained by the signal divider by using an orthogonal frequency division multiplexing method; a plurality of frequency shifters configured to shift each of the frequency bands of a plurality of modulation signals generated by the plurality of modulators from a baseband to a mutually different frequency band; and a signal sender configured to combine a plurality of modulation signals whose frequency bands are shifted by the plurality of frequency shifters and to transmit the signals to the coaxial cable.

Abstract: A method is disclosed wherein a portion of a sensor part of an optical fiber sensor is embedded in an adhesive between two joined members, and peeling in an adhesive joint of the two members is detected on the basis of measuring optical characteristics from the optical fiber sensor when the optical fiber sensor is irradiated with light from a light source while one member is vibrated by vibration means. The method comprises the steps of determining the temperature of the two members during measurement on the basis of the optical characteristics from the sensor part exposed outside of the adhesive; determining, on the basis of the temperature determined during the measurement, the measurement range in which the optical characteristics from the optical fiber sensor are measured; and measuring the variation in the optical characteristics from the optical fiber sensor within the determined measurement range while the member is being vibrated by the vibration means.

Abstract: A method for measuring shear load of a fastening tool, which comprises the steps of: positioning an optical fiber sensor on a surface of a fastening tool to be subjected to a measurement, or within the tool but near the surface thereof, so that the optical fiber sensor is positioned along a direction of an axis the fastening tool; and measuring the shear load acting on the fastening tool on the basis of a change in an optical characteristic of the optical fiber sensor that directly corresponds to a deformation of the fastening tool when the shear load is applied to the fastening tool.

Abstract: The present invention intends to propose an image pickup apparatus in which a plurality of camera head units can be easily installed at places close to each other. This image pickup apparatus includes a television camera system 10, in which video result of an external device 12 can also be transmitted through a single cable 16 which connects a camera control unit 13 and a camera head unit 15.

Abstract: In a video camera having three image pickup devices in which a pixel of one channel of channels forming three primary colors is spatially displaced from other pixels of two channels by 1/2 pixel, when three primary color signals output from the three image pickup devices are converted into digital three primary color signals, an aperture signal is formed from the digital three primary color signals, the aperture signal output is added to the digital three primary color signals and a digital video signal of a predetermined format is formed from the added signal, a clock frequency of an aperture signal forming circuit is set to be twice the clock frequencies of the image pickup devices, an A/D converting circuit and a video signal forming circuit.

Abstract: A gamma correction circuit converts digital video data to address data, reads out slope and intercept data for segments of a polygonal line approximation of a desired gamma correction characteristic stored at the address, and uses the read out data to generate a gamma corrected output video signal. Another gamma correction circuit directly uses digital video data to address previously stored level correction data, then uses the level correction data and a coefficient K to generate a gamma corrected output video signal.

Abstract: This digital telephone conference system provides improved cancellation of reflective signals which cause echo-singing problems, such as caused by hydrid mismatches, for any number of telephone sets. Each telephone set is sequentially sampled for time sharing, and alternate samples are given opposite polarity signs before being summed, thereby making approximately half of the signals of opposite phase, for any number of telephone sets, for effective cancellation. Also, each member of the conference receives a sum signal of all telephone sets except his own.