Abstract: [Task] In a power conversion system, a variation in PCS alternating current voltage is suppressed during a change operation to a self-contained run according to an instantaneous voltage drop-service interruption. [Means for solving the task] During an ordinary system voltage stabilization, with change switch 25 changed to the output side of APR control circuit 22 and change switch 400 changed to the output side of charge/discharge run PWM command value preparing section 200, the power conversion system is run in a charge/discharge run mode. If the instantaneous voltage drop or the service interruption occurs, change switch 25 is changed to the output side of the self-contained run change prior current command value preparing section 60 and the constant current discharge run is carried out in which the electric power is discharged for a predetermined time duration in response to the current command value of the self-contained run change prior current command value preparing section 60.

Abstract: In a nuclear power plant, a corrosion-resistant oxide film on a surface of the metal component of a reactor structure is exposed to a high-temperature water, the corrosion-resistant oxide film containing an oxide having a property of a P-type semiconductor, and a catalytic substance having a property of an N-type semiconductor is deposited on the oxide film. The oxide film maintains the property of the P-type semiconductor.

Abstract: In a nuclear power plant, a corrosion-resistant oxide film on a surface of the metal component of a reactor structure is exposed to a high-temperature water, the corrosion-resistant oxide film containing an oxide having a property of a P-type semiconductor, and a catalytic substance having a property of an N-type semiconductor is deposited on the oxide film. The oxide film maintains the property of the P-type semiconductor.

Abstract: There are provided an austenitic stainless steel having high stress corrosion crack resistance, characterized by containing, in percent by weight, 0.030% or less C, 0.1% or less Si, 2.0% or less Mn, 0.03% or less P, 0.002% or less S, 11 to 26% Ni, 17 to 30% Cr, 3% or less Mo, and 0.01% or less N, the balance substantially being Fe and unavoidable impurities; a manufacturing method for an austenitic stainless steel, characterized in that a billet consisting of the said austenitic stainless steel is subjected to solution heat treatment at a temperature of 1000 to 1150° C.; and a pipe and a in-furnace structure for a nuclear reactor to which the said austenitic stainless steel is applied.

Abstract: Provided is a ground flare in which a low-frequency vibration generated from a ground flare tower, such as a chimney, is properly adjusted to suppress it below a fixture-vibration generation limit, thereby preventing surrounding objects from resonating and vibrating. In a ground flare that burns a flammable exhaust gas with a burner at the lower end of a chimney, in which the lower end of the chimney and the periphery of the burner are surrounded by a windbreak, the low-frequency-noise sound pressure level of a ground flare tower composed of the chimney and the windbreak is reduced by selecting at least one of changing a natural frequency generated from the ground flare tower, using multiple ground flare towers, and installing a low-frequency-vibration absorber in the ground flare tower.

Abstract: This method of upgrading a biomass comprises: an upgrading step for performing upgrading treatment of a cellulose based biomass with an oxygen/carbon atomic ratio of at least 0.5, in presence of water and under a pressure of at least saturated water vapor pressure, and reducing said oxygen/carbon atomic ratio of said biomass to no more than 0.38, and a separation step for separating an upgraded reactant obtained from said upgrading step into a solid component and a liquid component.

Abstract: A nickel-based alloy and welding processes and consumables that use the alloy as a weld filler metal to fabricate, weld overlay, and repair components, including components of nuclear power plant reactors that contact the hot coolant water of the reactor. The nickel-based alloy consists of, by weight, 26 to about 30% chromium, 2 to about 4% iron, 2 to about 4% manganese, 2 to about 3% niobium, 1 to about 3% molybdenum, not more than 0.6% titanium, not more than 0.03% carbon, not more than 0.05% nitrogen, not more than 0.6% aluminum, not more than 0.5% silicon, not more than 0.01% copper, not more than 0.02% phosphorus, not more than 0.01% sulfur, with the balance nickel and incidental impurities.

Abstract: An optical fiber electric current sensor includes a polarization-splitter (13) that splits light outputted from a sensor fiber (11) into two polarization planes of which polarization directions are perpendicular to each other, a depolarizer (17) that depolarizes each of the polarization components from the polarization-splitter (13), light receiving element that converts the two lights that were depolarized by the depolarizer (17) to a first signal (S1) and a second signal (S2) respectively, and a signal processing unit (15) that, based on the first signal (S1) and the second signal (S2), determines the magnitude of a Faraday rotation applied to the linearly-polarized light, and thereby calculates a value of the current to be measured.

Abstract: To provide a torque measurement device capable of more accurately specifying positions of reflectors which are attached to a rotating body, and more accurately obtaining a torque of the rotating body. A pair of reflectors (14a, 14b) is provided on the surface of the rotating body (13) and has a spacing in the axial direction, reflected light data obtained by reflection of reflection patterns in the pair of reflectors (14a, 14b) is input and stored, a point of minimizing AIC is determined for a model of the reflected light data from the rotating body (13), and existence regions of the pair of reflectors (14a, 14b) are detected. Then, a twist amount of the rotating body (13) is calculated from the reflector positions specified by the detected existence regions of the pair of reflectors (14a, 14b), and the torque is calculated from the calculated twist amount of the rotating body.

Abstract: The present invention provides a mercury removal system and method for effectively removing a mercury component, which is present in a gas stream in an extremely small amount in wet gas cleaning. The mercury removal system in wet gas cleaning includes a water washing tower for introducing therein a target gas containing a mercury component and transferring the mercury component into an absorbing solution, a flash drum (10) for flashing the absorbing solution discharged from the water washing tower to separate the absorbing solution into a gas component and waste water, an oxidation treatment means (1) for adding an oxidizing agent to the absorbing solution at the preceding stage of the flash drum, and a waste water treatment means for subjecting to coagulation sedimentation treatment the separated waste water containing the mercury component at the following stage of the flash drum to dispose of the mercury component as sludge.

Abstract: An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When a cylindrical tubular body (2) is improved in its residual stress by locally irradiating an outer-circumferential surface of a welded portion (C) of the tubular body (2) with laser beams (5a) and by moving an irradiation area (s) in an circumferential direction, a plurality thermocouples (9) are installed on the tubular body (2) to be improved, a temperature history of the outer surface of the tubular body (2) by the irradiation of the laser beam (5a) is managed by measuring the temperature history itself.

Abstract: A fluid measurement system includes a long focus optical system at a CCD camera, and an image processing means for comparing particle images taken at two time points for analysis. The system further includes a high-pass filter for leaving high frequency components at a predetermined frequency and higher from the luminance signal of the image, so that a turbulence structure occurring in the fluid to be measured is extracted, and the turbulence structure is captured and its image is taken. Therefore, the flow field of an inaccessible fluid to be measured can be analyzed.

Abstract: To provide a power generation system that prevents a reduction in the efficiency of a steam turbine due to an aperture adjustment of a turbine governing valve. There is provided a power generation system comprising: a furnace in which a solid fuel or a liquid fuel is combusted; a steam turbine that generates electric power by rotating a turbine rotor using steam generated by the furnace; a superheater that is provided between the furnace and the steam turbine and that superheats the steam; a first steam piping that connects the furnace to the superheater; a second steam piping that connects the superheater to the steam turbine; a first valve provided in the first steam piping; a turbine governing valve provided in the second steam piping; and a control section that adjusts an aperture of the first valve according to a load of the steam turbine.

Abstract: A fluid measurement system includes a long focus optical system at a CCD camera, and an image processor for comparing particle images taken at two time points for analysis. The long focus optical system is provided with a shield which shields a part including a central portion of a main mirror at an arbitrary shield rate. As a result, the particle image of a tracer is enlarged with its contour kept clear, that is, in focus, and therefore, the image having a luminance which allows analysis by the PIV method can be taken in spite of use of the long focus optical system.

Abstract: An optical fiber electric current sensor includes a polarization splitter (13) that splits output light from a sensor fiber (11) into two polarization components of which polarization planes intersect with each other; and a signal processing unit (15) that converts the two split polarization components into first and second signals (Px) and (Py) by opto-electric conversion, multiplies a ratio (Sx) between direct current component and alternating current component of the first signal (Px) and a ratio (Sy) between direct current component and alternating current component of the second signal (Py) by different coefficients, and calculates a difference value therebetween.

Abstract: A technology for accurately measuring with the use of an ultrasonic flowmeter the flow rate through a nuclear reactor water supply piping interposed between a nuclear reactor and a nuclear reactor water supply pump. In a reactor coolant cleaning system (30), piping to be joined with a reactor water supply system (10) is branched, thereby forming an auxiliary path (A) to be similarly joined with the reactor water supply system (10). The auxiliary path (A) is provided with a restriction part (C) having an inside diameter narrower than that of other parts of the auxiliary path (A) to complete a nuclear reactor water supply piping structure. Through this structure, cavitation bubbles are generated from the restriction part (C). An ultrasonic transducer (40) is disposed between the nuclear reactor (1) and the auxiliary path (A) in the piping for composing the reactor water supply system (10), thereby conducting measurement of the flow rate of fluid within the piping.

Abstract: A simple constitution together with an easy calibration of output by realizing a fast light intensity detection method is realized without using the carrier signal. An optical sensor, including: a sensor to which light from a light source is lead, and by which light intensity of the light is modulated based on a physical value; light receiving elements 61 and 62 receiving two elements of divided light PA and PB having polarized waves which are orthogonally crossing each other; a variable optical attenuator operating light which is received by the light receiving elements 61 and 62; and a variable amplifier operating output signals from the light receiving elements 61 and 62, wherein both a zero point of a sensor output and sensitivity are calibrated based on a light attenuation factor or an amplification factor which is adjusted when a physical value is detected by calculating a ratio between a sum and a difference of outputs of the light receiving elements 61 and 62.

Abstract: This invention relates to a method of determining stability of unstable equilibrium point (UEP) computed by using BCU method, comprising selecting UEP computed by using BCU method, obtaining a test vector Xtest for the selected UEP, say XUEP using the following equation: Xtest=Xspost+0.99(XUEP?Xspost) where Xspost is the SEP, and checking boundary condition of XUEP by simulating system trajectory of post-fault original system starting from Xtest.

Abstract: A process quantity measurement method with which an engine output is accurately measured in a relatively simple manner. Torque of an engine is measured based on the amount of torsion of the output shaft of the engine, and an engine output is obtained based on the measured torque. On the other hand, an engine output is calculated based on input and output heat quantity, and a difference between the engine output based on the torque and the engine output based on the input and output heat quantity is obtained in advance. When the engine is operated, the previously obtained difference is added to the engine output that is based on the calculated input and output heat quantity to obtain the engine output.

Abstract: A doppler ultrasonic flowmeter including: an ultrasonic transmission member for casting ultrasonic pulses onto the fluid within a fluid tube, which is to be measured, along a measurement line from an ultrasonic transducer, a flow-speed distribution measurement unit for receiving ultrasonic echoes reflected from the measurement region due to ultrasonic pulses cast onto the fluid to be measured so as to measure the flow-speed distribution of the fluid to be measured in the measurement region; a flow measurement unit for measuring the flow of the fluid to be measured; and a transducer position adjusting mechanism for adjusting the relative position of a pair of ultrasonic transducers serving as the ultrasonic transmission member, a first transducer and a second transducer, which are disposed away one from another along the axial direction of a fluid tube.