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: Provided is a technique for performing a precise flow rate measurement of a large-bore pipeline without causing any aliasing. Ultrasonic pulses are transmitted at a first repetition frequency and at a second repetition frequency different from the first one, and a fluid velocity distribution measuring means measures a first flow velocity distribution for the first repetition frequency and a second flow velocity distribution for the second repetition frequency.

Abstract: An object is to provide a gate valve capable of preventing operational deficiencies caused by particulate materials accumulating in a valve box, thus providing superior sealing properties and high durability, having a simple structure, and allowing inspection and maintenance to be performed easily.

Abstract: There is provided a non-contact vibration measurement technique for a structure by continuously imaging the structure from a far distance using a PIV system and measuring vibration through image analysis.

Abstract: Disclosed is an ultrasonic Doppler flow measurment system that achieves flow measurement regardless of the temperature of a fluid. A temperature sensor 7 is combined with a pipe 1 to measure the temperature of a fluid 2. A controller 9 calculates a frequency that will cause cavitation when an ultrasonic transducer 4 exerts an ultrasonic vibration on the fluid 2 on the basis of a temperature measured by the temperature sensor 7 and controls a sinusoidal oscillator 6.

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: An object of the present invention is to provide an arcing horn system having a highly efficient dynamic current shutoff property including a dynamic current shutoff capability, for example, enough for the short circuit fault and other object thereof is to provide an arcing horn system capable of repeatedly maintaining the good dynamic current shutoff capability.

Abstract: It is an object to increase a reprocessing speed of spent nuclear fuel and to obtain uranium having a high purity and a plutonium mixture reusable as it is at a low cost through a simple procedure. The spent nuclear fuel 1 is subjected to fluorination using fluorine 2 in a fluorination step 3, and as a result, uranium, a mixture of uranium and plutonium and a fission product are separated and recovered independently of one another. The plutonium fluoride volatilized in the fluorination is recovered along with a fixing agent and then passed through an oxidative conversion step 8, thereby recovering a mixture of uranium and plutonium oxides 9. Since the uranium can be recovered in a high purity, it is managed very easily when reused or saved. Further, since the uranium and plutonium are recovered as a mixture thereof, fuel reproduction cost is decreased and prevention of proliferation is strengthened.

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: Disclosed is an ultrasonic Doppler flow measurment system that achieves flow measurement regardless of the temperature of a fluid. A temperature sensor 7 is combined with a pipe 1 to measure the temperature of a fluid 2. A controller 9 calculates a frequency that will cause cavitation when an ultrasonic transducer 4 exerts an ultrasonic vibration on the fluid 2 on the basis of a temperature measured by the temperature sensor 7 and controls a sinusoidal oscillator 6.

Abstract: A control system for a sodium-sulfur battery, which is composed of a plurality of battery modules connected in series, includes a control device having at least a temperature measuring unit for measuring a temperature of each battery module, a voltage measuring unit for measuring a voltage thereof, and a current measuring unit for measuring a current thereof assembled as a single control device. Preferably, the system includes a unit for detecting the end of discharge and the end of charge. Thus, the time lag in the detection of the end of discharge and the end of charge may be prevented. The reliability of a NaS battery during long-term operation is improved. A fluctuation in the power consumption of heaters during the driving of the NaS battery is reduced. The space required for installing power equipment such as a transformer may be omitted.

Abstract: A MOX nuclear fuel assembly employable either for a thermal neutron reactor employing UO2 as the nuclear fuel and light water as the moderator/coolant or for a thermal neutron reactor employing the MOX fuels as the nuclear fuel and light water as the moderator/coolant is provided with only one kind of MOX nuclear fuel rods each of which has relatively large magnitude of the enrichment grade of the fissionable Pu-s or Pu239 and Pu241, the quantity of the MOX nuclear fuel rods being relatively small.

Abstract: In a method of reducing corrosion of a metal material, a substance such as semiconductor for generating an electric current by thermal excitation is coated or adhered on a metal material surface, to be exposed to a water having a high temperature of 150° C. or more, of a boiler and ducts or pipes, to which hot water heated by the boiler contacts, of a thermal electric power plant or a nuclear reactor structural material or ducts or pipes surrounding the reactor in a nuclear power plant.

Abstract: A thermal efficiency diagnostic of a combined power generation plant is performed by using measurement data relative to energy input/output of the respective equipment of the combined power generation plant, recording the design values of heat balance, using measurement data having high measuring accuracy as standard parameters, conducting an optimum state estimation by adjusting the key parameters, which largely affect the diagnostic results so as to be consistent with the standard parameters, so that each deviation of the reference parameters becomes minimum and the probability of the heat balance becomes maximum in a whole plant, comparing the heat balance thus determined with the heat balance based on a design value, analyzing the degree of contribution of performance of each equipment to the thermal efficiency and specifying the equipment which causes the thermal efficiency deterioration in accordance with the degree of contribution.

Abstract: A ceramic-coated blade of a gas turbine and a method of producing the same, in which the thickening of an Al2O3 layer at the interface between a ceramic layer and a primary layer is sufficiently prevented for a long period of time, thereby positively suppressing the separation of the ceramic layer. Using powder of MCrAlY alloy (Co—32%Ni—21%Cr—8%Al—0.5%Y), a primary layer (alloy coating layer) is formed on a surface of a substrate made of a heat-resistant Ni base alloy (Rene'-80). Further, a heat-resistant ceramic layer, comprising a mixture of ion-conductive ZrO2—8wt. %Y2O3 ceramic and insulative ceramic (e.g. Al2O3), is formed on the alloy coating layer. This mixture has a columnar structure in which columnar crystals are grown by a gas phase in a direction of a thickness of the coating, or a porous structure in which flattened particles brought about from molten particles caused to fly at high velocity are laminated.

Abstract: A MOX nuclear fuel assembly employable either for a thermal neutron reactor employing UO2 as the nuclear fuel and light water as the moderator/coolant or for a thermal neutron reactor employing the MOX fuels as the nuclear fuel and light water as the moderator/coolant is provided with only one kind of MOX nuclear fuel rods each of which has relatively large magnitude of the enrichment grade of the fissionable Pu-s or Pu239 and Pu241, the quantity of the MOX nuclear fuel rods being relatively small.

Abstract: A torque measuring device including a light irradiation element for irradiating a light, and a control unit operatively connected to the irradiation element so as to branch the light into a plurality of lights as beams and control a beam diameter of the respective lights so as to irradiate the lights on a surface of a member to be measured. The torque measuring device further includes a plurality of reflectors disposed on the surface of the member to be measured so as to change reflection state of the respective lights, a plurality of detectors for detecting the changes of intensities of the respective reflected lights and generating signals thereof, and a signal processor for processing the generated signals and operating a rotation period on the basis of the generated signals thereby to calculate a torque of the member to be measured.

Abstract: A thermal efficiency diagnostic of a combined power generation plant is performed by using measurement data relative to energy input/output of the respective equipment of the combined power generation plant, recording the design values of heat balance, using measurement data having high measuring accuracy as standard parameters, conducting an optimum state estimation by adjusting the key parameters, which largely affect the diagnostic results so as to be consistent with the standard parameters, so that each deviation of the reference parameters becomes minimum and the probability of the heat balance becomes maximum in a whole plant, comparing the heat balance thus determined with the heat balance based on a design value, analyzing the degree of contribution of performance of each equipment to the thermal efficiency and specifying the equipment which causes the thermal efficiency deterioration in accordance with the degree of contribution.

Abstract: A feed water heating system for heating a feed water for a power-generating plant having a steam turbine, a condenser and a steam generator, comprises: a steam injector unit for receiving a plurality of bled steams having different pressures extracted from the steam turbine and an effluent water discharged from the condenser to mix the effluent water with the plurality of bled steams to raise the temperature and pressure of a mixture of the effluent water with the plurality of bled steams to deaerate and discharge the temperature and pressure raised mixture.

Abstract: A ceramic-coated blade of a gas turbine and a method of producing the same, in which the thickening of an Al.sub.2 O.sub.3 layer at the interface between a ceramic layer and a primary layer is sufficiently prevented for a long period of time, thereby positively suppressing the separation of the ceramic layer. Using powder of MCrAlY alloy (Co-32% Ni-21% Cr-8% Al-0.5% Y), a primary layer (alloy coating layer) is formed on a surface of a substrate made of a heat-resistant Ni base alloy (Rene'-80). Further, a heat-resistant ceramic layer, comprising a mixture of ion-conductive ZrO.sub.2 -8 wt. % Y.sub.2 O.sub.3 ceramic and insulative ceramic (e.g. Al.sub.2 O.sub.3), is formed on the alloy coating layer. This mixture has a columnar structure in which columnar crystals are grown by a gas phase in a direction of a thickness of the coating, or a porous structure in which flattened particles brought about from molten particles caused to fly at high velocity are laminated.