Abstract: An optical transmitter for converting an input data series into an optical multi-level signal and for outputting the same, includes an LUT in which data for executing optical multi-level modulation is stored and from which first modulation data and second modulation data are output based on the input data series. A DAC converts the first modulation data by D/A conversion to generate a first multi-level signal. A DAC converts the second modulation data by D/A conversion to generate a second multi-level signal. A dual-electrode MZ modulator includes a first phase modulator for modulating light from a light source in accordance with the first multi-level signal and a second phase modulator for modulating light from the light source in accordance with the second multi-level signal, and combines an optical signal from the first phase modulator and an optical signal from the second phase modulator to output the optical multi-level signal.

Abstract: An optical receiving apparatus includes: an A/D converting circuit; a received-signal demodulating circuit that demodulates a received digital signal from the A/D converting circuit into an m-bit received signal; a soft-decision-data generating circuit that generates n-bit (n?m) soft-decision data based on the m-bit received signal; and an error correcting circuit that performs error correction based on the n-bit soft-decision data and outputs an error-corrected received signal. The soft-decision-data generating circuit generates soft-decision data of n bits (n=p+1) that corresponds to a determination result according to 2n?1 soft-decision thresholds, by using an MSB of the m-bit received signal as hard-decision data, and by using, as reliability information, a result of comparison between a plurality of bits (k bits, where k?m) on an MSB side of the m-bit received signal and a fixed threshold, or p bits (p?m?k) selected from (m?k) bits on an LSB side of the m-bit received signal.

Abstract: An optical modulator includes first and second modulation waveguides, a demultiplexer, first and second phase adjustment waveguides that changes phases of a light of the first and second modulation waveguides, a multiplexer that combines light outputs from the first and second phase adjustment waveguides, a gain controller and a modulator bias controller in which voltages of the first and second modulation signals are controlled so that a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the first modulation waveguide has a predetermined phase is equal to a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the second modulation waveguide has a predetermined phase. A phase-adjustment bias controller that controls phase amounts changed by the first and second phase adjustment waveguides so as to cancel phase errors.

Abstract: An FEC frame structuring device includes a multi-lane distributing unit that distributes a data frame to be transmitted to n lanes, FEC coding units each performs FEC coding of the distributed data frame independently for each of the n lanes to generate an FEC frame, a multiplexing unit that multiplexes the FEC frame from the FEC coding units by relating to m channels of an optical signal, a demultiplexing unit that demultiplexes the m channels of the received optical signal by relating to the n lanes, FEC decoding units each performs FEC decoding of the demultiplexed FEC frame independently for each of the n lanes, and a multi-lane synchronizing unit that synchronizes the n lanes with each other after the FEC decoding performed by the FEC decoding units to reconstruct the original data frame.

Abstract: Provided is a multi-value optical transmitter in which a DC bias may be controlled to be stabilized so as to obtain stable optical transmission signal quality in multi-value modulation using a dual-electrode MZ modulator. The multi-value optical transmitter includes: D/A converters for performing D/A conversion on first and second modulation data which are set based on an input data series, so as to generate a first and a second multi-value signal, respectively; a dual-electrode MZ modulator including phase modulators for modulating light from a light source based on the first multi-value signal and the second multi-value signal, so as to combine optical signals from the phase modulators to output the optical multi-value signal; an optical output power monitor for detecting average power of the optical multi-value signal; and a DC bias control unit for controlling a DC bias for the dual-electrode MZ modulator, so as to maximize the average power.

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: An optical modulator includes first and second modulation waveguides, a demultiplexer, first and second phase adjustment waveguides that changes phases of a light of the first and second modulation waveguides, a multiplexer that combines light outputs from the first and second phase adjustment waveguides, a gain controller and a modulator bias controller in which voltages of the first and second modulation signals are controlled so that a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the first modulation waveguide has a predetermined phase is equal to a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the second modulation waveguide has a predetermined phase. A phase-adjustment bias controller that controls phase amounts changed by the first and second phase adjustment waveguides so as to cancel phase errors.

Abstract: A repeater includes a variable optical attenuating unit that collectively attenuates WDM optical signal input, an optical-attenuation adjusting unit that adjusts attenuation in the variable optical attenuating unit, and an optical amplifying unit that collectively amplifies and outputs the WDM optical signal collectively attenuated, to a downstream side. An optical-attenuation adjusting unit includes an input level detector; an output level detector; an output-level transmitting unit that receives information of a signal level of WDM optical signal output by a repeater at an upstream side and transmits information of a signal level of the WDM optical signal detected by the output level detector to a repeater at a downstream side; and an attenuation amount controller that controls the variable optical attenuating unit by calculating an attenuation amount thereof based on information of a signal level detected by the input level detector and a signal level received by the output-level transmitting unit.

Abstract: An optical transmitter generating an arbitrary optical waveform including an analog optical waveform, which is capable of controlling a bias to a Null point easily. The optical transmitter modulates light from a light source by an optical modulator with use of a data sequence being an electric signal, to thereby generate the arbitrary optical waveform, and includes: a light intensity detector detecting intensity of output light of the optical modulator; a data signal generator generating the data sequence; an average modulation degree calculator calculating an average modulation degree of the data sequence based on the data sequence; and a bias controller performing bias control on the optical modulator based on the intensity of the output light detected by the light intensity detector and the average modulation degree of the data sequence calculated by the average modulation degree calculator.

Abstract: To prevent evaporated flux from being attached to rotation axes of motors which rotate fans positioned in a preheating zone, a main heating zone and a cooling zone and being solidified, the evaporated flux is efficiently and surely collected with the flux liquefying before the flux is solidified and having fluidity. A drain portion 20 constituting a flux collection apparatus 10A is formed at a side of a motor base 16 opposed to the fan and at a circumferential portion of the rotation axis 14. A surface of the drain portion 20 opposed to the fan is formed as an inclined surface 20A which is inclined from a level position of the motor base 16 to a discharge port 46 provided at a back side of the motor base 16.

Abstract: A pre-equalization optical transmitter includes: an RZ conversion circuit for generating an RZ-type input data sequence based on an NRZ-type input data sequence and a clock that is twice the speed of the NRZ-type input data sequence; a digital filter for generating pre-equalized data by a convolution operation between the RZ-type input data sequence and a desired transfer function corresponding to the wavelength dispersion of an optical fiber transmission path; D/A converters for performing D/A conversion on the pre-equalized data to output analog pre-equalized data; and a vector modulator for modulating light from a laser light source based on the analog pre-equalized data to output an RZ-type optical signal.

Abstract: A full-length cDNA encoding novel proteins involved in the control of cell proliferation (human Gros1-L and S) was successfully isolated from the human testis cDNA libraries. A full-length cDNA encoding the mouse homologues of the human Gros1 (mouse Gros1-L and S) was also isolated. The colony forming activity of cells exogenously expressing Gros1-L was significantly reduced, while that of cells expressing Gros1 antisense RNA was significantly increased.

Abstract: To enable the circuit board to be fixed on a predetermined position and to be conveyed to the solder processing portion. Conveying hooks 10 that hold the printed circuit board W1 therebetween, conveying chains 15a, 15b that drive so that the conveying hooks 10 are movable from a heater part 4 to a solder bath 5, first frames 9A that guide the conveying chains 15a, 15b along the heater part 4, second frames 9B that guide the conveying chain 15 along the solder bath 5, and an absorbing member 124 that is provided between each of the first frames 9A and each of the second frames 9B and absorbs an expansion and contraction based on difference of any thermal expansion between the frames 9A, 9B and the conveying chains 15a, 15b are provided. Since the absorbing member 124 absorbs the expansion and contraction based on difference of any thermal expansion between the frames 9A, 9B and the conveying chains 15a, 15b, it is possible to prevent the conveying chains 15a, 15b from being deviated from the frames 9A, 9B.

Abstract: A differential code optical transmission and reception device including: a digital signal processing optical transceiver that converts information data into an optical signal and transmits it to a communication channel, a reception front end part that receives the optical signal from the communication channel, an O/E conversion part that converts the optical signal received from the communication channel into an electrical signal, a skew correction part that regulates or correct a skew between lanes contained in the electrical signal, a differential decoder that decodes a differential code of the skew corrected electrical signal, and a lane exchange/rotation part that rearranges the electrical signal having passed through the differential decoder into a lane state thereof at the time of transmission in cases where lane exchange has occurred in the communication channel.

Abstract: An optical transmission apparatus in which, even if a change is made in the bit rate of modulation signals that are inputted to a plurality of optical modulating units, the modulation signals do not suffer from phase shifting, thereby enabling achieving synchronous modulation in the plurality of optical modulating units and enabling achieving a high optical signal quality. The optical transmission apparatus includes: a plurality of optical modulating units that modulate light on the basis of modulation signals; and a delay amount control unit that, based on bit rate information indicating a bit rate of the modulation signals, controls delay amounts of the modulation signals to be inputted to the plurality of optical modulating units, such that the light is modulated in a synchronous manner in the plurality of optical modulating units.

Abstract: A full-length cDNA encoding novel proteins involved in the control of cell proliferation (human Gros1-L and S) was successfully isolated from the human testis cDNA libraries. A full-length cDNA encoding the mouse homologues of the human Gros1 (mouse Gros1-L and S) was also isolated. The colony forming activity of cells exogenously expressing Gros1-L was significantly reduced, while that of cells expressing Gros1 antisense RNA was significantly increased.

Abstract: According to one embodiment, a method is disclosed for manufacturing a semiconductor memory device. The method can include forming a plurality of protruding portions in band configurations on a major surface of a semiconductor layer to extend along a first direction parallel to the major surface. The method can include forming an inter-layer insulating film to cover the protruding portions and an inner surface of a trench between the protruding portions. The method can include forming a buried conductive portion by filling a first conductive material into a space inside the trench. The method can include exposing a buried conductive portion side surface by dividing the buried conductive portion along the first direction. The method can include filling a second conductive material into a void of the buried conductive portion exposed at the side surface. In addition, the method can include removing one portion of the second conductive material.

Abstract: To enable the circuit board to be fixed on a predetermined position and to be conveyed to the solder processing portion. Conveying hooks 10 that hold the printed circuit board W1 therebetween, conveying chains 15a, 15b that drive so that the conveying hooks 10 are movable from a heater part 4 to a solder bath 5, first frames 9A that guide the conveying chains 15a, 15b along the heater part 4, second frames 9B that guide the conveying chain 15 along the solder bath 5, and an absorbing member 124 that is provided between each of the first frames 9A and each of the second frames 9B and absorbs an expansion and contraction based on difference of any thermal expansion between the frames 9A, 9B and the conveying chains 15a, 15b are provided. Since the absorbing member 124 absorbs the expansion and contraction based on difference of any thermal expansion between the frames 9A, 9B and the conveying chains 15a, 15b, it is possible to prevent the conveying chains 15a, 15b from being deviated from the frames 9A, 9B.

Abstract: An optical transmitter for converting an input data series into an optical multi-level signal and for outputting the same, includes an LUT in which data for executing optical multi-level modulation is stored and from which first modulation data and second modulation data are output based on the input data series. A DAC converts the first modulation data by D/A conversion to generate a first multi-level signal. A DAC converts the second modulation data by D/A conversion to generate a second multi-level signal. A dual-electrode MZ modulator includes a first phase modulator for modulating light from a light source in accordance with the first multi-level signal and a second phase modulator for modulating light from the light source in accordance with the second multi-level signal, and combines an optical signal from the first phase modulator and an optical signal from the second phase modulator to output the optical multi-level signal.

Abstract: An optical divider divides an optical input signal into a plurality of paths. A plurality of optical-to-electrical converters respectively converts the divided optical input signals into electrical signals. A plurality of discriminators respectively outputs discrimination results by discriminating the electrical signals output from the optical-to-electrical converters based on predetermined thresholds. An operational circuit performs a predetermined logical operation with the discrimination results output from the discriminators.