Abstract: An optical transceiver includes: an optical transceiver circuit; a light source device to multiplex light rays emitted from light source elements having different wavelengths, and output multiplexed light; a demultiplexer to demultiplex the light output from the light source device into wavelengths to supply the wavelengths to the optical transceiver circuit; monitors to monitor the wavelengths at output ports of the demultiplexer, respectively; and a wavelength controller to control the wavelengths of the light source elements, based on monitoring results of the monitors, wherein the demultiplexer includes unit circuits in each of which three asymmetric Mach-Zehnder interferometers having a predetermined arm length difference are cascaded in a tree shape, and each of the monitors is arranged at an output waveguide of an asymmetric Mach-Zehnder interferometer at an end of the cascaded tree, to be connected to the wavelength controller via a signal line.

Abstract: A resin film comprising a multilayer structure acrylic polymer and the film having an acid value of not more than 0.018 mmol/g in an acetone insoluble matter, an acid value of not more than 0.012 mmol/g in an acetone soluble matter, a glass transition temperature of not less than 80° C. and a thickness of 5 to 300 ?m is obtained by a method comprising emulsion polymerization for producing a latex comprising multilayer structure acrylic polymer, coagulating the latex comprising the multilayer structure acrylic polymer to obtain a slurry, washing and dehydrating the slurry, drying the dehydrated slurry to remove the multilayer structure acrylic polymer, mixing 0 to 35% by mass of an acrylic resin and 65 to 100% by mass of the removed multilayer structure acrylic polymer and subjecting the resultant mixture melted to an extrusion molding.

Abstract: A gas turbine includes a compressor, a combustor, a turbine, a generator, and a control apparatus, the compressor being provided with an air extraction valves, a plurality of inlet guide vanes, and a plurality of casing air extraction valves at its last stage, in which the control is carried out on at least one of the opening of the air extraction valve, the opening of the inlet guide vanes, and the number of openings of the casing air extraction valves which are defined as control parameters taking blade vibration stress values as indexes based on a compressor metal temperature included in behavior parameters of the gas turbine.

Abstract: A gas turbine includes a compressor, a combustor, a turbine, a generator, and a control apparatus, the compressor being provided with an air extraction valves, a plurality of inlet guide vanes, and a plurality of casing air extraction valves at its last stage, in which the control is carried out on at least one of the opening of the air extraction valve, the opening of the inlet guide vanes, and the number of openings of the casing air extraction valves which are defined as control parameters taking blade vibration stress values as indexes based on a compressor metal temperature included in behavior parameters of the gas turbine.

Abstract: A resin film comprising a multilayer structure acrylic polymer and the film having an acid value of not more than 0.018 mmol/g in an acetone insoluble matter, an acid value of not more than 0.012 mmol/g in an acetone soluble matter, a glass transition temperature of not less than 80° C. and a thickness of 5 to 300 pm is obtained by a method comprising emulsion polymerization for producing a latex comprising multilayer structure acrylic polymer, coagulating the latex comprising the multilayer structure acrylic polymer to obtain a slurry, washing and dehydrating the slurry, drying the dehydrated slurry to remove the multilayer structure acrylic polymer, mixing 0 to 35% by mass of an acrylic resin and 65 to 100% by mass of the removed multilayer structure acrylic polymer and subjecting the resultant mixture melted to an extrusion molding.

Abstract: A gas turbine cooling system efficiently cools a first-stage turbine wheel and attachment portions of first-stage turbine blades. The gas turbine cooling system includes a group of impingement cooling holes provided in a partition wall as a stationary component that separates an exit space of a compressor and a wheel space located upstream of a turbine wheel for ejecting compressed air in the exit space toward the turbine wheel and attachment portions of the turbine blades.

Abstract: The invention provides a gas turbine cooling system that efficiently cools a first-stage turbine wheel and the attachment portions of first-stage turbine blades. A gas turbine comprises: a compressor 1 for compressing air; a combustor 2 for combusting the air compressed by the compressor 1 with fuel; and a turbine 3 driven by the combustion gas generated by the combustor 2, the turbine 3 including at least one turbine wheel 12a having turbine blades 11a on an outer circumferential section thereof. A gas turbine cooling system comprises a group of impingement cooling holes 32, provided in a partition wall 16a that separates the exit space 42 of the compressor 1 and the wheel space 43a located upstream of the turbine wheel 12a, for ejecting the compressed air 101 in the exit space 42 toward the turbine wheel 12a and the attachment portions of the turbine blades 11a.