Abstract: A single-fiber bidirectional optical ring system includes: a central station; slave stations; and a network which connects the central station and the slave stations in a ring shape by optical fibers.

Abstract: A single-fiber bidirectional optical ring system includes: a central station; slave stations; and a network which connects the central station and the slave stations in a ring shape by optical fibers.

Abstract: An optical communication system includes: a plurality of optical transmission devices converting a first data signal that is an electrical signal into an optical packet signal; an optical coupler coupling optical packet signals; an optical coupler branching the optical transmission signal generated through coupling; a plurality of optical reception devices converting the optical transmission signal generated through branching into a second data signal that is an electrical signal; and a control unit controlling operation of the optical transmission devices and the optical reception devices.

Abstract: An optical communication system includes a plurality of optical transmitters, a plurality of first optical couplers provided respectively corresponding to the plurality of optical transmitters, a plurality of optical receivers, and a plurality of second optical couplers provided respectively corresponding to the plurality of optical receivers, in which each of the plurality of first optical couplers splits an optical signal transmitted by the corresponding optical transmitter and outputs the optical signal to each of the plurality of second optical couplers, each of the plurality of second optical couplers merges a plurality of optical signals output from the plurality of first optical couplers and outputs the merged signal to the corresponding optical receiver, and the plurality of optical transmitters alternately transmits the optical signals.

Abstract: A deterioration diagnosis device includes: a temperature acquisition unit acquiring a temperature of an optical transceiver including a laser diode outputting an optical transmission signal; a bias current acquisition unit acquiring a bias current flowing through the diode; a correction function calculation unit calculating a correction function representing a relationship between the acquired temperature and bias current; a temperature correction value calculation unit calculating a temperature correction value for a bias current acquired at the time of deterioration diagnosis, using the correction function; a corrected bias current calculation unit correcting the bias current acquired at the time of the deterioration diagnosis, using the temperature correction value; and a bias current change amount calculation unit determining a state of the laser diode by comparing an initial bias current with a corrected bias current.

Abstract: A life prediction method for an optical module that keeps optical output constant by controlling a bias current that is applied to a laser diode includes, by a life prediction device: acquiring a current value of the bias current from the optical module; holding an initial bias current value that is an initial current value of the bias current; calculating the number of digits of a difference value between the bias current value and the initial bias current value, and determining whether there is an increase in the number of digits; calculating a time interval at which occurrence of the increase in the number of digits is detected; and estimating a life of the optical module using the time interval, a first threshold, and the number of digits.

Abstract: A refrigeration cycle apparatus is provided with a refrigerant circuit, a refrigerant tank circuit, and a degassing pipe. The refrigerant circuit is configured by connecting a compressor, a flow path switching apparatus, a first heat exchanger, a decompressing apparatus, and a second heat exchanger. The refrigerant tank circuit is connected to the first and second heat exchangers in parallel with the decompressing apparatus. The degassing pipe has a first end and a second end. The flow path switching apparatus is configured to switch a flow of refrigerant discharged from the compressor to any of the first and second heat exchangers. The refrigerant tank circuit contains a refrigerant tank. The degassing pipe has the first end connected to the refrigerant tank and has the second end connected to at least any of the refrigerant circuit and the refrigerant tank circuit.

Abstract: A controller in a refrigeration cycle apparatus performs a refrigerant recovery operation when switching an operation mode from a defrosting mode to a heating mode. During the refrigerant recovery operation, by rotating a fan of a blower while monitoring a pressure at a discharge side of the compressor, the controller is configured to perform feedback control to cause a high-pressure side pressure to be close to a high-pressure side target pressure value. During the refrigerant recovery operation, by controlling a driving frequency of the compressor while monitoring a pressure at a suction side of the compressor, the controller is configured to perform feedback control to cause a low-pressure side pressure to be close to a low-pressure side target pressure value.

Abstract: In a refrigeration cycle apparatus, a controller is configured to, when a defrost mode is started, control a first pressure reducing device is controlled to adjust a flow rate of refrigerant to bring a degree of superheat of the refrigerant at a suction side of a compressor close to a target value, control a flow path switching device to form a first flow path through which the refrigerant released from the compressor flows to a first heat exchanger; perform a refrigerant release operation of opening one of a second pressure reducing device and a valve and closing the other of the second pressure reducing device and the valve, and perform a refrigerant collection operation of opening the second pressure reducing device and the valve, with the flow path switching device retained to form the first flow path, after the refrigerant release operation.

Abstract: A controller in a refrigeration cycle apparatus performs a refrigerant recovery operation when switching an operation mode from a defrosting mode to a heating mode. During the refrigerant recovery operation, by rotating a fan of a blower while monitoring a pressure at a discharge side of the compressor, the controller is configured to perform feedback control to cause a high-pressure side pressure to be close to a high-pressure side target pressure value. During the refrigerant recovery operation, by controlling a driving frequency of the compressor while monitoring a pressure at a suction side of the compressor, the controller is configured to perform feedback control to cause a low-pressure side pressure to be close to a low-pressure side target pressure value.

Abstract: A method for correcting an organic EL display including a volatile memory (MV), a non-volatile memory having a slower write speed than that of the volatile memory, and a control unit, the method to be performed by the control unit includes: performing cumulative processing for updating cumulative values in the volatile memory every first period; performing transfer processing for transferring the cumulative values from the volatile memory to the non-volatile memory every second period longer than the first period; delaying timing of the transfer processing in part of the display pixels according to the write speed of the second memory; and delaying start timing of the cumulative processing in the part of the display pixels according to the timing of the transfer processing, or switching an order of transfer of the cumulative values in the transfer processing between a first order and the reverse order of the first order.

Abstract: A refrigeration cycle apparatus is provided with a refrigerant circuit, a refrigerant tank circuit, and a degassing pipe. The refrigerant circuit is configured by connecting a compressor, a flow path switching apparatus, a first heat exchanger, a decompressing apparatus, and a second heat exchanger. The refrigerant tank circuit is connected to the first and second heat exchangers in parallel with the decompressing apparatus. The degassing pipe has a first end and a second end. The flow path switching apparatus is configured to switch a flow of refrigerant discharged from the compressor to any of the first and second heat exchangers. The refrigerant tank circuit contains a refrigerant tank. The degassing pipe has the first end connected to the refrigerant tank and has the second end connected to at least any of the refrigerant circuit and the refrigerant tank circuit.

Abstract: In a refrigeration cycle apparatus, a controller is configured to, when a defrost mode is started, control a first pressure reducing device is controlled to adjust a flow rate of refrigerant to bring a degree of superheat of the refrigerant at a suction side of a compressor close to a target value, control a flow path switching device to form a first flow path through which the refrigerant released from the compressor flows to a first heat exchanger; perform a refrigerant release operation of opening one of a second pressure reducing device and a valve and closing the other of the second pressure reducing device and the valve, and perform a refrigerant collection operation of opening the second pressure reducing device and the valve, with the flow path switching device retained to form the first flow path, after the refrigerant release operation.

Abstract: A method for correcting an organic EL display including a volatile memory (MV), a non-volatile memory having a slower write speed than that of the volatile memory, and a control unit, the method to be performed by the control unit includes: performing cumulative processing for updating cumulative values in the volatile memory every first period; performing transfer processing for transferring the cumulative values from the volatile memory to the non-volatile memory every second period longer than the first period; delaying timing of the transfer processing in part of the display pixels according to the write speed of the second memory; and delaying start timing of the cumulative processing in the part of the display pixels according to the timing of the transfer processing, or switching an order of transfer of the cumulative values in the transfer processing between a first order and the reverse order of the first order.

Abstract: When multiplexed signal lights are amplified by optical amplifiers, a value of a monitor signal is compared with a threshold equivalent to a value of the monitor signal when noise indexes of the multiplexed signal lights start increasing. Next, when the value of the monitor signal is equal to or larger than the threshold, that is, when the powers of the multiplexed signal lights are large, a gain constant control is performed to amplify the multiplexed signal lights. Conversely, when the value of the monitor signal is smaller than the threshold, that is, when the powers of the multiplexed signal lights are small, an output constant control is performed to amplify the multiplexed signal lights.

Abstract: When multiplexed signal lights are amplified by optical amplifiers, a value of a monitor signal is compared with a threshold equivalent to a value of the monitor signal when noise indexes of the multiplexed signal lights start increasing. Next, when the value of the monitor signal is equal to or larger than the threshold, that is, when the powers of the multiplexed signal lights are large, a gain constant control is performed to amplify the multiplexed signal lights. Conversely, when the value of the monitor signal is smaller than the threshold, that is, when the powers of the multiplexed signal lights are small, an output constant control is performed to amplify the multiplexed signal lights.

Abstract: An optical communication system includes an optical-signal transmission unit transmitting an existing optical signal and a low-rate-signal superimposition unit superimposing a low-rate signal on the existing optical signal by intensity modulation. It further includes: a low-rate-signal extraction unit that extracts the low-rate signal from the existing optical signal on which the low-rate signal is superimposed and converts the extracted low-rate signal into a low-rate electric signal; an add-on optical-signal transmission unit that transmits an add-on optical signal; a low-rate-signal superimposition unit that superimposes a low-rate signal on the add-on optical signal by the intensity modulation based on the low-rate electric signal; and a repeater that repeats the add-on optical signal on which the low-rate signal is superimposed, to a transmission destination.

Abstract: In an optical transfer system, an optical transmission unit generates an optical signal in which respective polarization components are alternately present on a time axis, a time period during which the respective polarization components are simultaneously present on the time axis is substantially zero, and a symbol repetition cycle of optical signals of the respective polarization components becomes Ts, an optical reception unit causes an interference between local oscillation light and a received optical signal and converts an interfered optical signal to an electric signal, and a received electric-signal processing unit performs analog-digital conversion of an electric signal, elimination of a delay difference of Ts/2 between the respective polarized signal components, and adaptive equalization of a distortion other than the delay difference.

Abstract: By respectively abutting first and second outer diameter sections of a second metallic member against first and second inner diameter sections of a first metallic member, and energizing the first metallic member and the second metallic member using a pair of electrodes while pressurizing both metallic members in an axial direction thereof, a first junction where the first inner diameter section and the first outer diameter section are bonded and a second junction where the second inner diameter section and the second outer diameter section are bonded are formed between both metallic members, and a gap in which the metals do not come into contact with each other is formed between both junctions over a predetermined axial length. Accordingly, a high joint strength can be secured using less energy for bonding.

Abstract: Disclosed is a coating composition for a plastic label, which contains an oxetane compound, an epoxy compound, and a cyclic acetal and/or a poly(vinyl butyral). The coating composition excels in suitability for printing such as gravure printing or flexographic printing, cures rapidly to give excellent productivity, and after curing, gives a coating layer that excels in adhesion to a plastic base film and in toughness. A plastic label formed using the coating composition excels in surface scratch resistance and crumpling resistance, and therefore is particularly useful as a label for use in plastic containers, and metal containers such as bottle cans.