Kabushiki Kaisha Toshiba

Other

Renesas Electronics Corporation

Nec Electronics Corporation

Hidehiko Kuroda

Makoto Ochiai

Takahiro Miura

Kentaro Tsuchihashi

Fukashi Osakata

Masahiro Yoshida

Mikio Izumi

Kei Takakura

Michio Sato

Satoshi Yamamoto

Naoto Kume

Akira Tsuyuki

Kunihiko Nakayama

Makoto Takemura

Mitsuaki Shimamura

Shigeru Kanemoto

Mitsuhiro Enomoto

Kiyoto Oyagi

Yuka Takada

Tooru Ootsubo

Satoshi Okada

Kazuo Saito

Yoshihiro Yamashita

Masaki Yoda

Naruhiko Mukai

Osamu Kawakami

Katsuhiko Sato

Takashi Kokubo

Itaru Chida

Yoshiaki Ono

Akio Sumita

Toru Onodera

Tetsuro Aikawa

Ryoichi Saeki

Yukio Yoshimura

Fujio Shiraishi

Tatsuo Yamashita

Hiroaki Kenjyo

Hitoshi Sakakida

Takuhisa Kondo

Shuuichi Umezawa

Hajime Obikawa

Masahiko Kuroki

Kunihiko Yokoyama

Teturo Aikawa

Hidefumi Amanai

Kei Takaruka

A reactor state monitoring apparatus including: a first gamma ray-dose measurement device that detects and measures an atmospheric radiation dose caused by radioactive substances on a containment vessel side respective to a biological shielding wall surrounding a pressure vessel and outside the pressure vessel; a second gamma ray-dose measurement device that detects and measures a radiation dose on the pressure vessel side respective to the biological shielding wall; a fuel radiation measuring device that detects and measures a radiation dose of fuel in the pressure vessel; and a water amount evaluation device that calculates a difference between radiation doses measured by the fuel radiation measuring device and the first gamma ray-dose measurement device as a corrected fuel radiation dose, and acquires a cooling water level as a water level evaluation value, based on the radiation dose measured by the second gamma ray-dose measurement device and the corrected fuel radiation dose.

Reactor state monitoring apparatus and monitoring method thereof

A radiation detection apparatus includes a selecting unit that allows a light having a light emission wavelength and a polarization direction to pass thorough the selecting unit, an optical system that forms an image of the light, a photon detecting unit that observes the image formed by the optical system, and detects the photon in whole range of the entire image, a counting unit that calculates the number of the alpha rays based on a result of counting the photons derived from the light emission of gas excited by the alpha rays, whereby it is possible to sufficiently eliminate background light (noise light) even if background light is strong, and therefore observe weak light emission.

Radiation detection apparatus and radiation detection method

An alpha ray observation device and an alpha ray observation method are provided that can correctly evaluate a signal derived from alpha rays. The alpha ray observation device according to an embodiment includes a device housing, an incident window, a condenser, an optical path changer, and a first optical detector. The device housingis provided with an opening. The incident windowis provided at the opening, and can block beta rays. Emitted light originated by alpha rays caused from the measurement object set outside of the device housingenters the inside of the device housingthrough the incident windowwith beta rays being blocked, and is condensed by the condenser, and the optical path is changed by the optical path changer, and subsequently the light is detected by the first optical detector. The first optical detectoroutputs a signal according to the amount of detected light.

Alpha ray observation device and alpha ray observation method

A thickness measurement apparatus and method to measure an object to be inspected. The thickness measurement apparatus includes: an ultrasonic wave transmission/reception device that receives/transmits an ultrasonic wave to/from a wall of a pipe to be inspected, covered with a heat insulation material; a support device that supports the ultrasonic wave transmission/reception device from an outer surface of the pipe to be inspected; a thickness calculation device that measures a propagation time of the ultrasonic wave received/transmitted by the ultrasonic wave transmission/reception device, and calculates thickness of the pipe to be inspected; a calibration board with a predetermined thickness greater than a thickness of a dead zone of the ultrasonic wave transmission/reception device; and a calibration board adjustment device that moves the calibration board toward and away from a gap between the ultrasonic wave transmission/reception device and the outer surface of the pipe to be inspected.

Thickness measurement apparatus and method thereof

Provided is a liquid level measuring technique capable of measuring a liquid level with high accuracy even if a liquid stored in a container is boiling. The liquid level measuring apparatus includes: ultrasonic sensors each configured to transmit and receive an ultrasonic wave, the ultrasonic sensors being respectively set at a plurality of positions on an outer surface of a container that stores a liquid; a transmission/reception controlling unit configured to set, as a target, any one of the ultrasonic sensors at the plurality of positions and control the transmission and reception of the ultrasonic wave of the target; an intensity detecting unit configured to detect an intensity of the ultrasonic wave that satisfies at least 2&#x2266;N (N: natural number), of the ultrasonic waves that are reflected N times on an inner surface of the container; a gas/liquid determining unit configured to determine which of the liquid and a gas a reflection point on the inner surface is in contact with, on a basis of the detected intensity of the ultrasonic wave; and a level determining unit configured to determine a liquid level of the liquid on a basis of gas/liquid determination results respectively derived by the ultrasonic sensors at the plurality of positions.

Liquid level measuring apparatus, method, and program

An embodiment of a radiation detector has: a light collecting member; a photo detector that can receive light collected by the light collecting member and count number of photons; a wavelength selector that can selectively transmit light based on the light emission of gas caused by alpha rays by selectively transmitting light of a wavelength in a specific range; a shielding device that is can switch between an opened state in which it transmits light and a closed state in which it shields light; and a counting unit that calculates an alpha dose based on a difference calculated by subtracting number of noise photons detected in the photo detector within a predetermined time period when the shielding device is in the closed state from the number of photons received by the photo detector within the predetermined time period when the shielding device is opened state.

Radiation detector and radiation detection method

A vibration measuring apparatus for nuclear reactor internal structure includes a holder which has an opening contact on a surface of a pressure vessel of a nuclear reactor; a vibrator accommodated in the holder so as to transmit or receive an ultrasonic wave; a couplant with which the holder is filled up; and, a bias component applies a biasing force to the vibrator in the direction of the opening; The couplant is a solid state of metal material at normal temperature and change to liquid stage by heat transfer from the pressure vessel.

Vibration measuring apparatus for nuclear reactor internal structure and vibration measurement method therefor

A light detecting unit of an alpha ray observation device observes an alpha ray by measuring generated light that is generated by the alpha ray produced in a region of a to-be-measured object. The light detecting unit has a travel direction changing unit that changes the direction of travel of generated light, a light detector that detects direction-changed light, which is the generated light after the direction of travel is changed, and a shielding member that shields the light detector from radiation and has a portion that is provided on the line from the to-be-measured object to the light detector. The shielding member may also surround the perimeter of the light detector and have an opening to allow generated light to reach the travel direction changing unit.

Light detection unit and alpha ray observation device

According to an embodiment, a nuclear reactor monitoring device comprises: an ultrasonic wave transmission means which is installed on the outside surface of a reactor pressure vessel and transmits ultrasonic pulses to the interior of the reactor pressure vessel; an ultrasonic wave receiving means which is installed on the outside surface of the reactor pressure vessels and receives reflected pulses including ultrasonic waves from the ultrasonic pulses reflected by an inspection object in the reactor pressure vessel; a preprocessing means which specifies and removes the reflected ultrasonic pulses generated in the wall of the reactor pressure vessel from the reflected pulse signal received by the ultrasonic wave receiving means or selectively extracts the reflected pulse signal; and a calculation means which determines the vibration of the inspection object from the reflection pulse signal processed by the preprocessing means in accordance with the observation time of the inspection object.

Nuclear reactor vibration monitoring device and monitoring method thereof

A nuclear reactor vibration surveillance system has a first ultrasonic transducer for transmission, an ultrasonic transmitter, a second ultrasonic transducer for reception, an ultrasonic receiver, a signal processor, and a display unit. The first ultrasonic transducer for transmission is arranged on the outer surface of a reactor pressure vessel and is configured to convert a transmission signal into an ultrasonic pulse signal and allow the ultrasonic pulse to be transmitted to a reactor internal component. The second ultrasonic transducer for reception is arranged on the outer surface of the reactor pressure vessel and is configured to receive a reflected ultrasonic pulse reflected by the reactor internal component and convert the received reflected ultrasonic pulse into a reception signal.

Nuclear reactor vibration surveillance system and its method

A laser maintenance apparatus including a laser irradiation device which includes a first optical element for irradiating detection laser light on a test object to detect an ultrasonic wave; a second optical element for irradiating generation laser light on a test object so as to excite the ultrasonic wave; and an optical system container for containing the first and second optical element. The reflection direction of the first optical element and the reflection direction of the second optical element are arranged at an angle along the circumferential direction of the test object. The light reflected by the first optical element is irradiated at a position different than light reflected by the second optical element, and the laser irradiation positions of the light reflected by the first and second optical elements are different in the axial direction and the circumferential direction of the test object.

Laser-based maintenance apparatus using ultrasonic wave detection for flaw analysis and repair

A surface inspecting method including irradiating a laser light to a test object to generate an ultrasonic wave, irradiating a second laser light at a position apart by a known distance from a position where the laser light is irradiated and receiving a reflection light thereof, and correcting a generation surface wave of a received ultrasonic wave by using an ultrasonic wave other than the generation surface wave to thereby detect a flaw of the test object. A characterization of the generation surface wave is divided or integrated by the same characterization of the ultrasonic wave other than the generation surface wave included in an output signal to obtain a performance index value and obtain a depth of the flaw by applying the performance index value to a calibration curve in which a corresponding relation between the performance index value and the depth of the flaw is obtained preliminarily.

Laser-based maintenance apparatus for inspecting flaws based on a generated surface wave

A laser maintenance apparatus including a laser system which includes an optical system for emitting, in a first irradiation condition, a generation laser beam for generating an ultrasonic wave in a portion of an object on which maintenance is to be performed, and including a laser source configured to generate and detect a detection laser beam which interacts with the ultrasonic wave generated by the laser light beam in the first condition. The laser maintenance apparatus also includes a light transmitting device for transmitting laser light emitted from the laser system, a laser irradiation device for irradiating laser light transmitted by the light transmitting device to the object portion, and a transporting/scanning mechanism for transporting the light transmitting device and the laser irradiation device to a portion near the object portion, and scanning over an arbitrary range at the object portion.

Laser ultrasonic detection device including a laser oscillating device which includes a seed laser oscillating element

A surface inspecting method for inspecting a flaw of a test object using a surface wave and estimating a depth of the flaw of the test object from an attenuation ratio of a frequency of a generation wave, the surface inspecting method including calculating a power spectrum of generation wave generating the flaw of the test object; integrating the power spectrum of the generation wave passing the flaw of the test object and calculating an integration value thereof; converting the integration value into a flaw depth based on a calibration created beforehand and calculating the flaw depth of the test object; and displaying the calculated flaw depth of the test object.

Laser-based maintenance apparatus for inspecting flaws

A frequency synthesizer includes first and second frequency dividers for receiving and frequency-dividing a signal generated by a voltage-controlled oscillator, a frequency mixer for mixing output signals of the first and second frequency dividers, and a third frequency divider for receiving and frequency-dividing a signal having one frequency of two frequencies that are output by the frequency mixer. The first, second third and frequency dividers and the frequency mixer are provided in a feedback loop within a PLL circuit between the voltage-controlled oscillator and the phase comparator. The phase comparator has a first input terminal to which a signal to which a signal that is output by the third frequency divider is input and a second input terminal to which a reference clock signal that is output by a reference signal generator is input. A loop filter supplies the voltage-controlled oscillator with a voltage that is based upon result of the phase comparison by a phase comparator. The voltage-controlled oscillator supplies the first and second frequency dividers with a signal that oscillates at a frequency corresponding to the voltage input to the oscillator.

Frequency synthesizer

Growing community of inventors

Yokohama, Japan

Hidehiko Kuroda